Sixth International Symposium on Isotopomers - Geophysical ...

<strong>Sixth</strong> <strong>International</strong> <strong>Symposium</strong> on Isotopomers 

ISI 2012: 18- 22 June 2012 

Carnegie Institution of Washington 

1530 “P” Street, NW, Washington, DC, USA 

<strong>Sixth</strong> <strong>International</strong> <strong>Symposium</strong> 

on Isotopomers 

18 - 22 June 2012, Carnegie Institution of Washington 

Washington, DC, USA 

! 

ISI 2012 Washington 

ISI 2010 Amsterdam 

ISI 2008 Odaiba 

ISI 2006 La Jolla 

ISI 2003 Stresa 

ISI 2001 Yokohama 

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ISI 2012: 18- 22 June 2012 


1530 “P” Street, NW, Washington, DC, USA 

SIXTH INTERNATIONAL SYMPOSIUM ON ISOTOPOMERS 

18 – 22 JUNE 2012, WASHINGTON, DC, USA 

ISI 2012 ORGANIZING COMMITTEE: 

HUIMING BAO, LOUISIANA STATE UNIVERSITY 

JAMES FARQUHAR, UNIVERSITY OF MARYLAND 

SHUHEI ONO, MASSACHUSETTS INSTITUTE OF TECHNOLOGY 

DOUGLAS RUMBLE, GEOPHYSICAL LABORATORY 

WITH SPECIAL THANKS TO MEMBERS OF PREVIOUS ORGANIZING COMMITTEES: 

M. S. JOHNSON, UNIVERSITY OF COPENHAGEN 

THOMAS ROCKMANN, UTRECHT UNIVERSITY 

JOEL SAVARINO, LABORATOIRE DE GLACIOLOGIE ET GEOPHYSIQUE DE L’ENVIRONMENT 

M. H. THIEMENS, UNIVERSITY OF CALIFORNIA, SAN DIEGO 

SYLVIA WALTER, UTRECHT UNIVERSITY 

WE WISH TO HONOR THE FOUNDER OF ISI WITH GRATITUDE AND RESPECT: 

NAOHIRO YOSHIDA, TOKYO INSTITUTE OF TECHNOLOGY 

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WITH GRATEFUL THANKS TO THE SPONSORS OF ISI 2012! 

Deep Carbon Observatory 

Dr. R. M. Hazen 

Dr. Craig M. Schiffries 

https://dco.gl.ciw.edu/ 

Dr. Russell J. Hemley, Director 

https://www.gl.ciw.edu 

US Department of Energy 

Dr. Nicholas Woodward, Program Manager 

Geosciences 

Basic Energy Sciences 

http://science.energy.gov/bes/ 

Elementar Americas 

Dr. Robin Sutka 

http://www.americas.elementar.de/index.php?id=about 

Thermo Fisher Scientific 

Dr. Charles Douthitt 

Dr. Andreas Hilkert 

www.thermoscientific.com 

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ISI 2012: 18- 22 June 2012 



TABLE OF CONTENTS 

PAGE 

ORGANIZING COMMITTEE 2 

SPONSORS 3 

INTRODUCTION 5 

THE DUPONT CIRCLE NEIGHBORHOOD 7 

PROGRAM 10 

POSTERS 15 

ABSTRACTS 18 

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SIXTH INTERNATIONAL SYMPOSIUM ON ISOTOPOMERS: ISI 2012 

Welcome to the <strong>Sixth</strong> <strong>International</strong> <strong>Symposium</strong> on Isotopomers in Washington, DC, USA. The 

first ISI was held in 2001 in Yokohama, Japan, the second ISI in 2003 in Stresa, Italy, the third ISI 

in 2006 in La Jolla, USA, the fourth in 2008 in Odaiba, Japan, and the fifth in 2010 in Amsterdam, 

the Netherlands. In the tradition of previous ISI’s, the <strong>Sixth</strong> ISI brings together researchers from a 

wide variety of disciplines united in their determination to use the latest developments in isotope 

studies to advance their understanding. The <strong>Symposium</strong> is meant to provide opportunities for 

participants to learn from each other, to make new friends, and to initiate new research 

collaborations. The contribution of students to ISI 2012 is especially welcomed and valued 

because of the undeniable benefits of their fresh perspectives and enthusiasm. 

Special thanks are due to the Drs. Bob Hazen and Craig Schiffries of the Deep Carbon 

Observatory and to Dr. Rus Hemley of the Geophysical Laboratory for contributing materially to 

ISI 2012. 

Support for the travel expenses of graduate students is provided by the Geosciences Division of 

Basic Energy Sciences, US Department of Energy, Dr. Nick Woodward, Program Director. 

The generous support of Dr. Robin Sutka of Elementar Americas 

and of Drs. Chuck Douthitt and Andreas Hilkert 

of Thermo-Fisher is gratefully acknowledged. Websites: 

, 

The members of the Scientific Committee, Drs. Huiming Bao, James Farquhar, Shuhei Ono and 

Doug Rumble would like to thank Ms. Pam Woodard, Ms. Lauren Cryan, Mr. Jeff Lightfield, Ms. 

Christina Hoag, Ms. Lindsay Calderone, Dr. Zan Peeters, Ms. J.M. Martin, and Ms. Karen Rumble 

for their help. The welcoming hospitality of Ms. Alexis Fleming and her colleagues at Carnegie’s 

headquarters is gratefully acknowledged. 

The entire community of isotope researchers owes a debt of gratitude to Prof. Naohiro Yoshida, 

Tokyo Institute of Technology, for his leadership in establishing the <strong>International</strong> <strong>Symposium</strong> on 

Isotopomers as a definitive outpost on the frontier of knowledge. And we, the members of the 

scientific committee, are grateful for his encouragement and wise counsel. 

CARNEGIE INSTITUTION OF WASHINGTON 

(History and description from CIW website http://carnegiescience.edu/. Please visit website for 

additional information) 

In 1901, Andrew Carnegie retired from business to begin his career in philanthropy. He decided to 

endow an independent research organization that would increase basic scientific knowledge. The 

institution was incorporated by the U. S. Congress in 1903. There are six departments, listed 

below. 

The President of the Carnegie Institution of Washington is Dr. Richard A. Meserve to whom ISI 

2012 is indebted for hosting the symposium in Carnegie’s administration building. The Director of 

the Geophysical Laboratory is Dr. Russell J. Hemley to whom ISI 2012 is grateful for substantial 

support. 

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Department of Embryology, Baltimore, Maryland The Department of Embryology was founded 

in 1913 in affiliation with the department of anatomy at The Johns Hopkins University. Until the 

1960s its focus was human embryo development. Since then the researchers have addressed 

fundamental questions in animal development and genetics at the cellular and molecular levels. 

Geophysical Laboratory, Washington, D.C. Researchers at the Geophysical Laboratory (GL), 

founded in 1905, examine the physics and chemistry of Earth’s deep interior, the high-pressure 

behavior of materials, the stable isotope composition of rocks and minerals, and the interactions of 

fossil and living organisms with their environment. 

Department of Global Ecology, Stanford, California Established in 2002, Global Ecology is the 

newest Carnegie department in over 80 years. Using innovative approaches, these researchers are 

picking apart the complicated interactions of Earth’s land, atmosphere, and oceans to understand 

how global systems operate. 

Department of Plant Biology, Stanford, California The Department of Plant Biology began as a 

desert laboratory in 1903 to study plants in their natural habitats. Over time their research has 

evolved to the study of photosynthesis. 

Department of Terrestrial Magnetism, Washington, D.C. The Department of Terrestrial 

Magnetism was founded in 1904 to map the geomagnetic field of the Earth. Today the department 

is home to an interdisciplinary team of astronomers and astrophysicists, geophysicists and 

geochemists, cosmochemists and planetary scientists. These Carnegie researchers are discovering 

planets outside our solar system, determining the age and structure of the universe, and studying 

the causes of earthquakes and volcanoes. 

The Observatories, Pasadena, California, and Las Campanas, Chile. The Observatories were 

founded in 1904 as the Mount Wilson Observatory. The famous 200 inch telescope on Mt. 

Palomar, California, saw first light in 1949, a product of collaboration between CalTech and CIW. 

Carnegie’s Las Campanas observatory now offers unparalled viewing of the sky of the southern 

hemisphere. 

CASE: Carnegie Academy for Science Education and First Light In 1989, Maxine Singer, 

president of Carnegie at that time, founded First Light, a free Saturday science program for middle 

school students from D.C. public, charter, private, and parochial schools. The program teaches 

hands-on science, such as constructing and programming robots, investigating pond ecology, and 

studying the solar system and telescope building. First Light marked the beginning of CASE, the 

Carnegie Academy for Science Education. Since 1994 CASE has also offered professional 

development for D.C. teachers in science, mathematics, and technology. 

ISI 2012 

The site of ISI 2012 is the administrative headquarters of the Carnegie Institution of 

Washington located at 1530 “P” Street, NW, Washington, DC, 20005, USA (aka Carnegie 

Institution of Science). Lectures will be given in the Auditorium (at the top of the accompanying 

figure). Lunch and coffee-tea service will take place in the Ballroom. The Icebreaker will be held 

in the Rotunda. The Banquet will be set up in the Ballroom and Rotunda. Posters will be exhibited 

in the Board Room, North Aisle, and Ballroom. 

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THE CIW NEIGHBORHOOD: DUPONT CIRCLE 

The neighborhood surrounding CIW’s headquarters (Dupont Circle) is the home of a diversified 

population that is young and sometimes noisy but all in good fun. Please do not hesitate to enjoy 

the restaurants, bars, and the U-street jazz clubs (home of the great Duke Ellington) of the Dupont 

Circle area. The East-West streets of the neighborhood are designated alphabetically, P, Q, R, S, T, 

U. The North-South streets are numbered 14 th , 15 th , 16 th , 17 th . Major avenues slash diagonally 

across the rectangular grid thanks to M. Pierre Charles l’Enfant, the Capital City’s Paris-inspired 

designer. Please note that Washington is divided into four quadrants NW, NE, SW, and SE. It is 

important to bear this division in mind because street addresses are repeated in the different 

quadrants. By remembering that the meeting site is located at the corner of 16 th and P, NW, you 

may easily find your way to local venues. The closest Metro station is on the Red Line at Dupont 

Circle . Convenient local bus transportation is provided by 

DCCirculator http://dccirculator.com/Home/BusRoutesandSchedules/CirculatorRouteMap.aspx. 

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DUPONT CIRCLE SIGHT-SEEING 

Anderson House and the Phillips Collection are walking-distance from CIW’s headquarters and 

worth a trip. There are many other sites of great interest in Washington, DC. Please note that all of 

the Smithsonian Museums < http://www.si.edu/ > e.g. Natural History, National Gallery, Air & 

Space, Hirshhorn, Sackler, Freer, etc. etc. are all open to the public free of charge. 

(1): Anderson House : Historical collections of the American Revolution 1775 – 1783. THE 

SOCIETY of the CINCINNATI. 2118 Massachusetts Avenue, NW, Washington, DC, 20008. 

http://societyofthecincinnati.org/202.785.2040 

(2): 

Paintings by Renoir and Rothko, Bonnard and O'Keeffe, van Gogh and 

Diebenkorn are among the many stunning impressionist and modern works at this converted 

mansion. 1600 21st St., NW, Washington, DC 20009 Near 21st and Q Streets, NW. 

http://phillipscollection.org/index.aspx 

DUPONT CIRCLE RESTAURANTS 

There are many, many restaurants near CIW. Consult the ZAGAT guide or on-line YELP < 

http://www.yelp.com/c/dc/restaurants> or TripAdvisor < http://www.tripadvisor.com/Restaurantsg28970-Washington_DC_District_of_Columbia.html>. 

The following list of local restaurants was provided by Lindsay Calderone, Zan Peeters, and Karen 

& Doug Rumble. 

Agora: Mediterranean Fusion.1527 17th St. NW, Washington, DC 20036 | 202-332-6767. Greek 

& Turkish. some vegetarian. 

Birch & Barley: 1337 14 th Street, NW, Washintton, DC 20005. 202-567-2576. 

http://birchandbarley.com/ Artisanal beers, cosmopolitan food. 

Bistro Du Coin: 1738 Connecticut Avenue, NW - Washington, DC 20009. Tél: 202 234 6969. 

http://bistrotducoin.com/ French Bistro. 

Cork Wine Bar - 1720 14th Street, NW between the Streets R and S. (202.265.2675) 

http://www.corkdc.com/resthome.html. Tasty small plates and a great wine selection. 

Dukem: Ethiopian, some vegetarian. 12th and U Streets 1114 - 1118 U Street Washington D.C. 

20009 202.667.8735 . http://dukemrestaurant.com/ Ethiopian. 

Estadio - 1520 14th Street NW Washington, DC 20005 202-319-1404 http://estadio-dc.com/ 

Zan’s favourite Tapas restaurant. Spanish tapas. 

Hank's Oyster Bar: 1624 Q Street NW, Washington DC 20009 202.462.4265. 

http://www.hanksoysterbar.com/. Great seafood. 

Komi: http://komirestaurant.com/ 1509 17th Street NW (between P & Q Streets) Washington DC 

20036. (202) 332-9200. Pricey and tough to get reservations but worth it. 

Little Serow: 1511 17th Street NW Washington DC 20036http://www.littleserow.com/ Thai 

flavor combinations created here are quite spicy and fun. They don't take reservations but 

it's easy to get in if you come around 5 - 5:15pm and wait till they open at 5:30. Thai. 

Pearl Dive Oyster Palace: 1612 14th Street NW, Washington DC 20009. 202.319.1612. 

http://www.pearldivedc.com/intro. Creole-Louisiana seafood. 

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Posto - 1515 14th Street NW Washington, DC 20005 (Between P & Q Streets NW) 202.332.8613. 

http://www.postodc.com/ modern styling with Italian food. They have some outside 

seating which I prefer over sitting inside. Italian. 

Rice - 1608 14th st NW, Washington, DC 20009 202.234.2400. http://www.ricerestaurant.com/ 

Thai, takes reservations. 

Standard: 1801 14th street nw. on the corner of 14th and S streets, Washington, dc 20009 

http://www.standarddc.com/ Outdoor grill: barbeque, donuts, and draft beer. 

Sushi Taro: 1503 17th Street, NW, Washington, DC 20036, (17th & P street). 202-462-8999. 

Excellent Japanese (expensive), reservations essential. 

A Little Farther Away 

Kushi Izakaya & Sushi, 465 K Street, NW Washington DC 20001. 202.682.3123 

K & 5th, few blocks from Mt Vernon/Convention center metro http://eatkushi.tumblr.com/ 

Zan’s absolute favourite Sushi. 

Oyamel. 401 7th Street NW Washington, DC 20004 Corner of 7th & D Streets. 202.628.1005. 

http://www.oyamel.com/. Contemporary Mexican 

Rasika: 633 D Street, NW Washington, DC 20004. 202.637.1222. 

http://www.rasikarestaurant.com/pennquarter/about.php. Indian. 

Vinoteca: 1940 11th St NW, Washington, DC 20001. Intersection 11 th and U. 202.332.9463. 

http://www.vinotecadc.com/ Wine Bar & Food. Outdoor dining. 

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Program 

MONDAY, 18 JUNE 2012 

08:30 Registration at Carnegie Institution of Washington 

09:00 Welcome 

CLUMPED ISOTOPES co-chairs D. Rumble and M. Daeron 

09:15 DETERMINING THE ISOTOPIC ANATOMY OF COMPLEX MOLECULES USING HIGH-RESOLUTION, 

MULTI-COLLECTOR GAS SOURCE MASS SPECTROMETRY. John Eiler, Matthieu Clog, Paul Magyar, 

Alison Piasecki, Alex Sessions, Daniel Stolper. 

09:35 THEORETICAL CALCULATIONS OF EQUILIBRIUM CLUMPED ISOTOPE SIGNATURES BEYOND 

HARMONIC APPROXIMATIONS. Qi Liu, Xinya Yin, Yun Liu. 

09:55 A CLUSTER-MODEL-BASED CALCULATION METHOD FOR ISOTOPIC FRACTIONATIONS OF 

SOLIDS. Yun Liu, Mao Tang. 

10:15 BREAK. 

10:30 18 O 18 O AND 17 O 18 O IN THE ATMOSPHERE. Laurence Y. Yeung, Edward D. Young, Edwin A. 

Schauble. 

10:50 CLUMPED ISOTOPES APPLIED TO RESEARCH ON DIAGENESIS TOWARDS RESERVOIR 

CHARACTERIZATION. Anne-Lise Jourdan, Cédric M. John, Simon Davis. 

11:10 APPLICATION OF CLUMPED ISOTOPES TO BAHAMIAN SPELEOTHEMS. M. M. Arienzo, P. K. 

Swart, H. B. Vonhof, S. Murray. 

11:30 CLUMPED ISOTOPE ANALYSIS OF MODERN MARINE CARBONATES AND SILURIAN BRACHIOPODS. 

Ulrike Wacker, Jens Fiebig, Bernd Schoene, Axel Munnecke, Michael M. Joachimski, Alan D. 

Wanamaker. 

12:00 LUNCH 

SULFUR ISOTOPES co-chairs S. Ono and Y. Ueno. 

13:30 SELF-SHIELDING AND MOLECULAR DYNAMICS ORIGINS OF SULFUR MASS-INDEPENDENT 

FRACTIONATION DURING SO 2 UV PHOTOCHEMISTRY. Shuhei Ono, Andrew R. Whitehill, Harry D. 

Oduro 

13:50 MASS-INDEPENDENT FRACTIONATION FROM PHOTOEXCITATION OF SO 2 BY 250 TO 330 NM 

BROADBAND RADIATION IN THE PRESENCE OF ACETYLENE. Andrew Whitehill, Harry Oduro, Shuhei 

Ono. 

14:10 SO 2 PHOTOEXCITATION EXPLAINS MASS-INDEPENDENT FRACTIONATION IN PRESENT-DAY 

STRATOSPHERIC SULFATE. Shohei Hattori, Sebastian O. Danielache, Matthew S. Johnson, Johan A. 

Schmidt, Akinori Yamada, Yuichiro Ueno, Naohiro Yoshida. 

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14:30 BREAK. 

14:45 SPECTROSCOPIC PREDICTION OF Δ 36 S ANOMALY BY SO 2 PHOTOLYSIS AND THE ARCHAEAN 

ATMOSPHERE. Yuichiro Ueno, Sebastian O. Danielache, Matthew Johnson. 

15:05 HIGH-RESOLUTION CROSS SECTIONS OF ISOTOPIC SO 2 AND IMPLICATIONS FOR ARCHEAN S- 

MIF. J. R. Lyons, D. Blackie, G. Stark, J. Pickering. 

15:25 PHOTODISSOCIATION DYNAMICS OF SO AND SO 2 . S. Nanbu, T. Suzuki, A. D. Kondorskiy, I. 

Tokue, S. O. Danielache, Yuichiro Ueno. 

16:00 to 18:00 ICEBREAKER RECEPTION IN THE BALLROOM AND ROTUNDA 

TUESDAY, 19 JUNE 2012 

OXYGEN ISOTOPES co-chairs B. Luz and O. Abe. 

09:00 THE 17 O ANOMALY IN DEEP OCEANIC DISSOLVED O 2 . Boaz Luz 

09:20 VERTICAL DISTRIBUTION OF TRIPLE ISOTOPIC COMPOSITION OF DISSOLVED OXYGEN IN THE 

NORTHWESTERN PACIFIC. Osamu Abe 

09:40 TRIPLE OXYGEN ISOTOPE COMPOSITION OF TROPOSPHERIC CARBON DIOXIDE AND ITS 

SEASONAL VARIATION. B. Horváth, M.E.G. Hofmann, A.Pack. 

10:00 BREAK. 

10:15 GLOBAL LONG-TERM MEAN TRIPLE OXYGEN ISOTOPE COMPOSITION OF TROPOSPHERIC CO 2 

M.E.G. Hofmann, B.Horváth, A. Pack. 

10:35 CHANGES IN THE OXIDATION CAPACITY OF THE ATMOSPHERE REVEALED BY STABLE ISOTOPES 

IN NITRATE TRAPPED IN THE VOSTOK ICE CORE J. Savarino, J. Erbland , B. Alexander. 

10:55 UTILIZING THE ISOTOPIC COMPOSITION OF NITRATE TO INVESTIGATE DEPOSITION TO SUMMIT, 

GREENLAND M.G. Hastings, D.L. Fibiger, J.E. Dibb, C. Corr, L.G. Huey. 

11:15 PHOTOCHEMICAL ISOTOPE EFFECTS IN SNOWPACK NITRATE Carl Meusinger, Tesfaye A. 

Berhanu, Joseph Erbland, Florent Dominé, Joël Savarino, Matthew S. Johnson. 

11:35 STABLE WATER ISOTOPOLOGUES OF EAST ANTARCTIC (VOSTOK) SNOW SAMPLES: NEW 

INSIGHTS IN TEMPERATURE-δ 18 O RELATIONSHIP Renato Winkler, Amaelle Landais, Melanie Baroni, 

Alexey Ekaykin, Sonia Falourd, Jean Jouzel, Benedicte Minster, Jean Robert Petit, Frederic Prie, 

and Camille Risi. 

12:00 LUNCH 

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SULFUR ISOTOPES co-chairs J. Labidi and J. Schmidt. 

13:30 ACCURATE PHOTOLYTIC ISOTOPE EFFECTS FROM FIRST PRINCIPLES. J. A. Schmidt, M. S. 

Johnson, S. Hattori, R. Schinke. 

13:50 MAGNETIC ISOTOPE EFFECTS AS AN EXPLANATION FOR 33 S ANOMALIES IN TSR REACTIONS. 

Harry Oduro, Brian Harms, Herman O. Sintim, Alan J. Kaufman, George Cody and James 

Farquhar. 

14:10 INSIGHTS ON THE DEEP SULFUR CYCLE USING MULTIPLE S ISOTOPES IN MID-OCEAN RIDGE 

BASALTS. J. Labidi, P. Cartigny. 

DISCUSSION GROUP ON N 2 O STANDARDS Co-chairs N. E. Ostrom and Naohiro Yoshida. 

14:30 TO 15:30 

THE DEVELOPMENT OF INTERNATIONAL STANDARDS AND COMMON CALIBRATION PROTOCOLS FOR 

NITROUS OXIDE ISOTOPOMERS. N. E OSTROM 

15:30 to 17:30 POSTERS. 

N 2 O co-chairs K. Boering and S. Toyoda. 

WEDNESDAY, 20 JUNE 2012 

09:00 TOP-DOWN AND BOTTOM-UP: THE ISOTOPIC COMPOSITION OF ATMOSPHERIC NITROUS 

OXIDE IN THE SOUTHERN HEMISPHERE SINCE 1940. Kristie A. Boering 

09:20 DECADAL TIME SERIES OF TROPOSPHERIC N 2 O ISOTOPOMER RATIOS IN THE NORTHERN 

HEMISPHERE OBTAINED BY THE LONG-TERM OBSERVATION AT HATERUMA ISLAND, JAPAN. Sakae 

Toyoda, Natsuko Kuroki, Naohiro Yoshida, Kentaro Ishijima, Yasunori Tohjima, and Toshinobu 

Machida. 

09:40 LONGTERM SIMULATION OF TROPOSPHERIC AND STRATOSPHERIC N 2 O ISOTOPOMERS AND ITS 

APPLICATION TO GLOBAL BUDGET ESTIMATIONS Kentaro Ishijima, Sakae Toyoda, Masayuki 

Takigawa, Kengo Sudo, Takakiyo Nakazawa, Shuji Aoki, Thomas Röckmann, Jan Kaiser, Chisato 

Yoshikawa, Shinkoh Nanbu, Naohiro Yoshida. 

10:00 LASER BASED N 2 O ISOTOPOMER ANALYSIS BRIDGES THE GAP BETWEEN PURE CULTURE 

STUDIES AND FIELD APPLICATIONS J. Mohn, P. Wunderlin, B. Tuzson, H. Siegrist, A. Joss, L. 

Emmenegger. 

10:20 BREAK. 

10:35 THE ENIGMATIC NITROGEN BIOGEOCHEMISTRY OF LAKE VIDA, AN ISOLATED BRINE 

CRYOECOSYSTEM. Nathaniel E. Ostrom, Alison E. Murray, Gareth Trubl, Emanuele Kuhn. 

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10:55 ELUCIDATING SOURCE PROCESSES OF N 2 O FLUXES FOLLOWING GRASSLAND-TO-FIELD- 

CONVERSION BY MEASURING AND MODELING ISOTOPOLOGUE SIGNATURES OF SOIL-EMITTED N 2 O. 

Reinhard Well, Greta Roth, Dominika Lewicka-Szczebak, Anette Giesemann, Heiner Flessa. 

11:15 ISOTOPE FRACTIONATION FACTORS CONTROLLING ISOTOPOLOGUE SIGNATURES OF SOIL- 

EMITTED N 2 O PRODUCED BY DENITRIFICATION PROCESSES OF VARIOUS RATES. Dominika Lewicka- 

Szczebak, Reinhard Well, Laura Cardenas, Peter Matthews, Tom Misselbrook, Roland Bol, 

Richard Whalley, Andy Gregory. 

11:35 A NEW MODEL FOR NITROUS OXIDE ISOTOPOMER FORMATION FROM NITROXYL (HNO) 

DIMERIZATION IN AQUEOUS SOLUTION. Carsten Fehling, Gernot Friedrichs. 

12:00 LUNCH 

13:30 Afternoon off for sight-seeing. 

18:00 to 20:00 SYMPOSIUM BANQUET 

THURSDAY, 21 JUNE 2012 

OZONE-MIF co-chairs D. Babikov and G. Dominguez. 

09:00 MIXED QUANTUM/CLASSICAL THEORY FOR THE OZONE ISOTOPE EFFECT. Dmitri Babikov, 

Mikhail Ivanov. 

09:20 A POSSIBLE INTERPRETATION OF THE NON-MASS DEPENDENT ISOTOPIC FRACTIONATION 

EFFECT IN OZONE. François Robert, Peter Reinhardt. 

09:40 OZONE FORMATION ON COLD SURFACES: COSMOCHEMICAL IMPLICATIONS . Gerardo 

Dominguez, Terri Jackson, Morgan Nunn, Dimitri Basov, Mark Thiemens. 

10:00 BREAK. 

10:15 SPATIAL AND TEMPORAL VARIABILITY IN THE 17 O-EXCESS (Δ 17 O) OF SURFACE OZONE: 

AMBIENT MEASUREMENTS USING THE NITRITE-COATED FILTER METHOD. William C. Vicars, S. K. 

Bhattacharya, Joseph Erbland, Joël Savarino. 

10:35 OBSERVATION OF MASS-INDEPENDENT OXYGEN ISOTOPIC FRACTIONATION IN SOLID SILICATES 

THROUGH GAS PHASE REACTION: COSMOCHEMICAL IMPLICATIONS. Subrata Chakraborty, Petia 

Yanchulova, M. H. Thiemens. 

11:00 INVESTIGATING THE POSSIBILITY OF A HYPERFINE COUPLING (‘MAGNETIC ISOTOPE EFFECT’) 

MECHANISM FOR THE NON-MASS-DEPENDENT FRACTIONATION OF OXYGEN ISOTOPES CAUSED BY 

THERMAL DECOMPOSITION OF DIVALENT METAL CARBONATES. M. F. Miller, A. L. Buchachenko, E. 

Bailey, P. F. McMillan, and M. H. Thiemens. 

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11:20 ON THE MASS INDEPENDENT FRACTIONATIONS OF O, Hg, Si, Mg AND Cd DURING 

OPENSYSTEM EVAPORATION OR THERMAL DECOMPOSITION. P. Cartigny, J.M. Eiler, P. Agrinier, N. 

Assayag. 

11:40 UNUSUAL FRACTIONATION OF BOTH ODD AND EVEN MERCURY ISOTOPES IN PRECIPITATION FROM 

PETERBOROUGH, ONTARIO, CANADA. Jiubin Chen, Holger Hintelmann, Brian Dimock, Xinbin Feng. 

12:00 LUNCH 

OXYGEN co-chairs H. Bao and R. Tanaka. 

13:30 THE MARINOAN 17 O-DEPLETION (MOSD) EVENT: SINGULARITY, SYNCHRONICITY, AND 

DURATION. Huiming Bao. 

14:00 TOWARDS AN 17 O CHRONICLE OF THE ~635 MA GLOBAL GLACIAL MELTDOWN. Bryan 

Killingsworth, Justin Hayles, Chuanming Zhou, and Huiming Bao. 

14:20 EXPLORING THE USABILITY OF Δ 17 O OF BIOAPATITE AS PROXY FOR PAST ATMOSPHERIC CO 2 

CONCENTRATIONS. Andreas Pack, Alexander Gehler. 

14:40 AN IMPROVED CeO 2 METHOD FOR HIGH PRECISION MEASUREMENTS OF OXYGEN ISOTOPE 

ANOMALY Δ 17 O OF ATMOSPHERIC CARBON DIOXIDE. Sasadhar Mahata, S.K. Bhattacharya, Chung- 

Ho Wang, Mao-Chang Liang. 

15:00 KINETIC ISOTOPE FRACTIONATION EFFECT OBSERVED IN OXYGEN TRIPLE ISOTOPE RATIOS IN 

TERRESTRIAL SILICATE MINERALS. Ryoji Tanaka, Eizo Nakamura. 

15:30 to 17:30 POSTERS. 

FRIDAY, 22 JUNE 2012 

CARBON AND HYDROGEN ISOTOPES co-chairs G.S, Remaud and Y. Wang. 

09:00 DETERMINATION ON THE ABSOLUTE Δ(‰) SCALE OF SITE-SPECIFIC 13 C COMPOSITION BY 

NMR SPECTROMETRY: AN INTER-LABORATORY COMPARISON. G.S. Remaud, V. Silvestre, S. Akoka, 

R. Hattori, A. Gilbert, N. Yoshida, H. Sommer, W. Fieber, A. Chaintreau. 

09:30 SITE-SPECIFIC 2 H/ 1 H ANALYSIS BASED ON SOLID-STATE NMR: APPLICATIONS IN 

COSMO/GEO/BIOCHEMISTRY. Ying Wang, George Cody, Conel M. O’ D. Alexander, Marilyn Fogel, 

Bjørn Mysen. 

10:00 STABLE CARBON ISOTOPE RATIOS IN ATMOSPHERIC METHANOL. Holger Spahn, Christian 

Linke, Marc Krebsbach, Ralf Koppmann, Marcel vom Scheidt. 

10:15 BREAK 

10:45 A THIRTY YEAR COMPOSITE RECORD OF THE ISOTOPIC COMPOSITION OF ATMOSPHERIC 

METHANE FROM NORTH AMERICA Andrew Rice, D. G. Teama , Erica Hanson, Chris Butenhoff. 

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11:15 OXIDATION AND REDUCTION CAPABILITIES OF O 2─ ION-CONDUCTING SOLID ELECTROLYTE 

REACTOR FOR SAMPLING IN CF-IRMS. V.S. Sevastyanov, N.E. Babulevich, E.M. Galimov. 

12:00 BOX LUNCH 

13:30 END OF SYMPOSIUM 

POSTERS 

POSTERS ARE LIMITED IN SIZE TO 110 CENTIMETER BY 110 CENTIMETER. 

Posters will be on display throughout the symposium. There are two special poster 

sessions on Tuesday and Thursday from 15:30 to 17:30. 

AG 2 O: A NEW NON-MASS DEPENDENT STANDARD MATERIAL FOR OXYGEN ISOTOPE 

MEASUREMENTS. Tesfaye Ayalneh Berhanu, Joël Savarino, Amaelle Landais, Renato Winkler, 

Thomas Röckmann, Marion Früchtl, Jan Kaiser, Thomas Blunier, Corentin Reutenauer. 

FREQUENCY STABILIZED CAVITY RINGDOWN FOR ISOTOPE RATIO MEASUREMENTS. Thinh Q. Bui, 

David A. Long, Joseph T. Hodges, Charles E. Miller, Mitchio Okumura. 

WHY THERE ARE DISCREPANCIES BETWEEN THEORETICAL ESTIMATIONS AND EXPERIMENTAL 

RESULTS FOR THE EQUILIBRIUM THETA VALUE OF CO 2 -CeO 2 EXCHANGE? Xiaobin Cao, Yun Liu. 

ULTRAVIOLET SPECTROSCOPY OF 32 S, 33 S, 34 S AND 36 S SULPHUR DIOXIDE: FRACTIONATION BY 

PHOTOEXCITATION. S. O. Danielache, S. Hattori, M. S. Johnson, Y. Ueno, S. Nanbu, N. Yoshida. 

AN ISOTOPE VIEW ON IONISING RADIATION AS A SOURCE OF SULPHURIC ACID. Martin B. Enghoff, 

Nicolai Bork, Shohei Hattori, Carl Meusinger, Mayuko Nakagawa, Jens Olaf Pepke Pedersen, 

Sebastian Danielache, Yuichiro Ueno, Matthew S. Johnson, Naohiro Yoshida, and Henrik 

Svensmark. 

D/H FRACTIONATION BETWEEN C-H SPECIES IN CRUSTAL FLUIDS: AN IN-SITU EXPERIMENTAL STUDY. 

Dionysis I. Foustoukos, Bjorn O. Mysen. 

PARTIAL INTRAMOLECULAR 13 C ISOTOPE DISTRIBUTION IN LONG-CHAIN N-ALKANES (C 11 -C 31 ) 

DETERMINED BY ISOTOPIC 13 C NMR. Alexis Gilbert, Keita Yamada, Naohiro Yoshida. 

δ 13 C MEASUREMENT OF CERAMIDE BY A GAS CHROMATOGRAPHY-COMBUSTION-IRMS AS A TRACER 

FOR CLARIFYING THE MOISTURIZING EFFECT IN SKIN Hiroyuki Haraguchi, Keita Yamada, Rumiko 

Miyashita, Kazuhiko Aida, Masao Ohnishi, Naohiro Yoshida. 

ISOTOPIC FRACTIONATION IN OCS SINK REACTIONS AND IMPLICATION FOR THE SOURCE OF 

BACKGROUND STRATOSPHERIC SULFATE AEROSOLS . Shohei Hattori, Johan A. Schmidt, Sebastian O. 

Danielache, Matthew S. Johnson, Yuichiro Ueno, Naohiro Yoshida. 

PRESSURE BASELINE CORRECTION FOR ∆ 47 MEASUREMENTS. Bo He, Gerard Olack, Albert Colman. 

Page 15


ISI 2012: 18- 22 June 2012 



TRIPLE OXYGEN ISOTOPE EXPONENT FOR PHOSPHORIC ACID DECOMPOSITION OF CARBONATES . 

Magdalena E.G. Hofmann, Balázs Horváth, Andreas Pack. 

CO-ORGANIZATION OF FUNCTIONS OF ISOTOPY AND GRAVITATION IN EMBRYOGENESIS COHERENCE. 

A.A. Ivanov 

OXYGEN ISOTOPES (δ 18 O VS δ 17 O) CHARACTERIZE MICROBIAL PYRITE OXIDATION PRODUCTS: A NEW 

BIOMARKER? Issaku Kohl, Justin Christensen, Randy Mielke, Karen Ziegler, Bryan Killingsworth, 

Ed Young, and Max Coleman. 

ISOTOPIC SIGNATURES OF CO AND N 2 PHOTOLYSIS IN THE SOLAR NEBULA AND IN LABORATORY 

EXPERIMENTS . J. R. Lyons. 

VARIABILITY IN ISOTOPE RATIOS OF NITROGEN AND OXYGEN IN NITROUS OXIDE OF AIR OVER THE 

PACIFIC. Sasadhar Mahata , Cheng-Ting Lin, Danie Liang, and S. K. Bhattacharya. 

13-CARBON ISOTOPIC FRACTIONATION IN SECONDARY ORGANIC AEROSOL FORMATION C. Meusinger, 

U. Dusek, S.M. King, M. Bilde, Thomas Röckmann, M.S. Johnson. 

TRIPLE OXYGEN ISOTOPE ANALYSIS OF N 2 O USING MICROWAVE DISCHARGE DECOMPOSITION 

METHOD Arata Mukotaka, Sakae Toyoda, Naohiro Yoshida, Reinhard Well. 

13 C/ 12 C OF THE VOLATILE COMPOUNDS AND THEIR RELATION TO THE ENVIRONMENTAL VARIATION 

BASED ON THE GC-IRMS ANALYSES. Ariaki Murata, Uli Engelhardt, Peter Winterhalter, Keita 

Yamada, Naohiro Yoshida, Naoharu Watanabe. 

CHANGES IN THE Δ 18 O OF RECENTLY ALTERED CARBONATES: WATER OR TEMPERATURE? S.T. 

Murray, M.M. Arienzo, Y. Hernawati, P.K. Swart. 

QUADRUPLE SULFUR ISOTOPIC SYSTEMATICS OF ANOXYGENIC PHOTOSYNTHESIS AND SULFATE 

REDUCTION IN LOW SULFATE CONCENTRATION CONDITION. Mayuko Nakagawa, Yuichiro Ueno, 

Naohiro Yoshida. 

EXPERIMENTAL DATA ON VARIATIONS IN TRIPLE OXYGEN ISOTOPE EQUILIBRIUM FRACTIONATION 

EXPONENTS Andreas Pack, Nina Albrecht, Magdalena E.G. Hofmann, Balázs Horváth, Alexander 

Gehler. 

THE STABLE ISOTOPIC COMPOSITION OF CARBON MONOXIDE FROM GREENLAND FIRN SAMPLES 

COLLECTED AT NEEM S. L. Pathirana and T. Röckmann 

OXYGEN ISOTOPE COMPOSITION OF MELTWATER FROM A NEOPROTEROZOIC GLACIATION IN 

SOUTHERN CHINA. Y. Peng, H. Bao, C. Zhou, X. Yuan, T. Luo. 

RADIOACTIVE 35-SULFUR: A UNIQUE TRACER TO QUANTIFY ATMOSPHERIC AIR MASS TRANSPORT 

AND CLOCK THE SULFUR CYCLE. Antra Priyadarshi and Mark H Thiemens. 

THE PANORAMA (AKA “ISOTOPOLOGOSAURUS”): A NEW GAS SOURCE MASS SPECTROMETER FOR 

THE MEASUREMENT OF ISOTOPOLOGUES IN GEOCHEMISTRY D. Rumble, P. Freedman, E. D. Young, 

E. Schauble, W. Guo. 

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ISI 2012: 18- 22 June 2012 



GLOBAL OBSERVATION OF STRATO-MESOSPHERIC 18 OOO USING SMILES. Tomohiro Sato, Yasuko 

Kasai, Hideo Sagawa, Naohiro Yoshida. 

ISOTOPE EFFECTS IN N 2 O PHOTOLYSIS FROM FIRST PRINCIPLES. J. A. Schmidt, M. S. Johnson, and 

R. Schinke. 

ISOTOPIC FRACTIONATION DURING METHANE UPTAKE IN TEMPERATE FOREST SOIL. N. Suzuki, K. 

Koba, M. Itoh, K. Osaka, N. Ohte, Y. Tobari, K. Yamada and N. Yoshida. 

ISOTOPIC FRACTIONATION DURING PHOTODISSOCIATION OF SO. Tomoya Suzuki, Sebastian O. 

Danielache, Yuichiro Ueno, Shinkoh Nanbu. 

SPECTROSCOPIC MEASUREMENT OF 13 CH 3 D/ 12 CH 3 D AND 13 CH 3 D/ 12 CH 4 USING A MID-INFRARED 

DIFFERENCE-FREQUENCY-GENERATION SOURCE. Kiyoshi Tsuji 1 Hiroaki Teshima, Hiroyuki Sasada, 


ISOTOPOMER ANALYSIS OF N 2 O PRODUCTION-CONSUMPTION MECHANISMS IN BIOLOGICAL 

WASTEWATER TREATMENT UNDER NITRIFYING AND DENITRIFYING CONDITIONS. Azzaya 

Tumendelger, Sakae Toyoda, Naohiro Yoshida. 

FACTORS CONTROLLING THE CARBON ISOTOPIC VARIATION OF CAFFEINE. Chen Wu, Keita Yamada, 

Osamu Sumikawa, Akiko Matsunaga, Alexis Gilbert, Naohiro Yoshida. 

MEASUREMENT METHOD FOR INTRAMOLECULAR CARBON ISOTOPIC DISTRIBUTIONS OF SOME C2 

AND C3 METABOLITES. Keita Yamada, Alexis Gilbert, Na Li, Takanori Okuno, Naohiro Yoshida, 

Ryota Hattori, Nariaki Wasano, Satoshi Hirano. 

DEVELOPMENT OF A THREE DIMENSIONAL ATMOSPHERIC SULFUR ISOTOPIC MODEL. Chisato 

Yoshikawa, Sebastian O. Danielache, Yuichiro Ueno, Kengo Sudo, Kentaro Ishijima, Masayuki 

Takigawa, Naohiro Yoshida. 

VARIATIONS OF 13 C 16 O 18 O AND ITS CONTROLLING FACTORS IN THE ATMOSPHERE OF YOKOHAMA, 

JAPAN BASED ON THE OBSERVATION FROM 2007 TO 2011. Naizhong Zhang, Keita Yamada, 


ISOTOPOMER ANALYSIS OF N 2 O ACCUMULATED IN TEA FIELD SOIL IN SHIZUOKA, CENTRAL JAPAN. 

Yun Zou, Yuhei Hirono, Yosuke Yanai, Shohei Hattori, Sakae Toyoda, Naohiro Yoshida. 

ABSTRACTS 

Page 17


ISI 2012: 18- 22 June 2012 



VERTICAL DISTRIBUTION OF TRIPLE ISOTOPIC COMPOSITION OF DISSOLVED OXYGEN IN THE 

NORTHWESTERN PACIFIC 

Osamu Abe 

Nagoya University, Japan (osamu.abe@nagoya-u.jp) 

Oxygen-17 excess of dissolved oxygen calculated from δ 18 O and δ 17 O is not affected by 

oxygen consumption process but controlled only by processes of primary production and airwater 

gas transfer. Evaluating gross primary productivity using the 17 O-excess in ocean surface 

water are one of the most advanced geochemical researches for last 10 years. Oxygen-17 excess 

below ocean mixed/photic layer has not been much investigated because it might be out of focus 

for estimating present primary productivity, except for the purpose to correct diapycnal mixing 

effect on surface water. In principle, water mass which has not been affected both by 

photosynthesis and gas transfer after its separation from ocean surface could preserve 17 O-excess 

value where the water mass was at the surface. 

The purpose of this study is to determine the vertical distribution of 17 O-excess from the 

surface to the bottom of northwestern Pacific to know whether 17 O-excess could really preserve 

its “original” value after the long and dark travel. Near stations K2 and KNOT shown in the 

figure, water mass which has a density of 26.8 σ θ is observed at depth between 100 and 300 m. 

This water mass is mainly originated from bottom water in the Okhotsk Sea and spreading widely 

to entire northwestern Pacific, which is called North Pacific Intermediate Water (NPIW). NPIW 

is found at depth of 700 m at station S1. Samplings were conducted by two R/V Mirai cruises 

(MR10-06, Oct-Nov 2010; MR11-02, Feb-Mar 2011). Dissolved oxygen gas was purified by the 

method of Sarma et al. (2003) and its isotopic composition was determined by dual-inlet isotope 

ratio mass spectrometer (Thermo Scientific Delta Plus). Gross primary productivities at mixed 

layer estimated by 17 O-excess were well consistent with those by conventional light and dark 

bottle incubations for stations K2 and S1. 

Fig. Sampling locations for two cruises by R/V Mirai 

(JAMSTEC/Japan; MR10-06 and 11-02) 

Page 18


ISI 2012: 18- 22 June 2012 



APPLICATION OF CLUMPED ISOTOPES TO BAHAMIAN SPELEOTHEMS 

M. M. Arienzo 1 , P. K. Swart 1 , H. B. Vonhof 2 , S. Murray 1 

1 MGG/RSMAS University of Miami, Miami, FL email: marienzo@rsmas.miami.edu; 2 Vrije 

Universiteit Amsterdam, Amsterdam, Netherlands 

In this study we assess the commonly held view that changes in the δ 18 O of the carbonate 

material from stalagmites, represents principally a signal derived from the water, rather than from 

a change in temperature. For this purpose we have investigated rapid changes observed in 

stalagmites collected from flooded caves in the Bahamas, all of which are associated with rapid 

global scale climate change. One stalagmite from Abaco Island, Bahamas has been analyzed for 

both fluid inclusion and clumped isotopes from 13,000 to 31,000 ybp for subtropical paleoclimate 

across Heinrich events. Heinrich events are abrupt, cold events in the North Atlantic characterized 

in the sedimentary record by the deposition of ice rafted debris (IRDs). Clumped isotope analyses 

were conducted at the University of Miami and have been standardized using the method from 

Dennis et al. (2011) 1 . Carbonate stalagmite samples have been run in triplicate with an average 

∆47 standard error of 0.01. Fluid inclusion analysis was conducted at Vrije Universiteit 

Amsterdam with Dr. Hubert Vonhof 2 . The fluid inclusion and clumped isotope records support a 

decrease in temperature associated with Heinrich events. Although the clumped isotope 

temperatures are offset from the temperatures calculated using fluid inclusion and δ 18 O data, they 

also record a decrease in temperatures associated with the Heinrich event. The higher than 

expected temperatures calculated from the clumped isotopes are consistent with other studies 3,4 . 

The δD and δ 18 O from the fluid inclusion data fall near the meteoric water line and do not indicate 

a source water change over time. Rather, the data support a change in the amount of precipitation 

across these events, with a decrease in precipitation associated with Heinrich events, followed by 

an increase in precipitation after the Heinrich event. Although there are still uncertainties 

regarding the interpretation of the clumped isotope signal in stalagmites, 3,4 the change of 

temperature indicated by the fluid inclusions is supported by the calculated oxygen isotope ratio of 

the water based on the clumped isotopes. 

References Cited 

1. Dennis, K. J. et al. (2011) Geochim. Cosmochim. Acta, 75, 7117-7131. 

2. Vonhof, H. et al. (2006) Rapid Communications in Mass Spectrometry, 20:2553-2558 

3. Affek, H. P et al. (2008) Geochim. Cosmochim. Acta, 72(22), 5351-5360. 

4. Affek, H et al. (2010) AGU Fall Meeting Abstract #PP43C-07. 

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ISI 2012: 18- 22 June 2012 



MIXED QUANTUM/CLASSICAL THEORY FOR THE OZONE ISOTOPE EFFECT 

Dmitri Babikov and Mikhail Ivanov, 

Chemistry Department, Marquette University, Milwaukee, WI 53201, USA 

Our purpose is to develop a computationally affordable method for theoretical treatment of 

molecular dynamics in the recombination reactions that follow the energy transfer mechanism. The 

most important example is the reaction that forms ozone, where the metastable states of ozone 

( O ) are formed first, and then stabilized by collisions with bath gas (M): 

* 

3 

K 

eq * 

O + O 2 

←⎯⎯→ O 3 

, (1) 

* 

k 

O3 

+ M ⎯⎯⎯⎯→ O3 

stab 

+ 

M . (2) 

Over the past 10 years of active research on ozone, the step (1) has received the most of attention. 

The importance of DZPE-effect has been recognized by all authors working on this topic and has 

been introduced into the statistical, quantum and even into the classical trajectory theories of the 

process. In contrast, very limited progress has been made on modeling the step (2). This is quite 

unfortunate, since it is expected that this very process gives rise to the isotope effect, originating in 

the quantum symmetry and leading to the famous mass independent fractionations in the 

stratospheric ozone. The attempts of theorists to put a rigorous basis under this hypothesis have not 

been successful so far. 

We developed a mixed quantum/classical theory for treatment of the collisional energy 

transfer and the ro-vibrational energy flow in the reaction (2). We use rigorous time-dependent 

quantum mechanics (the wave packet method) to treat the internal vibrational motion of O , while 

* 

the rotational motion of O 

3 

and the collisional O * 3 

+ M motion are treated approximately 

(classical trajectories). The energy is exchanged between translational, rotational and vibrational 

degrees of freedom, while the total energy is conserved. This allows capturing all quantum effects 

associated with vibrational motion of O (i.e., zero-point energy, quantization of states, tunneling, 

* 

3 

scattering resonances), while the computational advantage is taken of the quasi-classical regime 

usually valid for rotational and translational degrees of freedom. 

This approach is applied to calculate third-order rate constants of the recombination 

reactions that form the 16 O 18 O 16 O (symmetric) and 18 O 16 O 16 O (asymmetric) isotopomers of ozone. 

* 

3 

References: [1] M. Ivanov and D. Babikov, J. Chem. Phys. 134, 144107 (2011). 

[2] M. Ivanov and D. Babikov, J. Chem. Phys. 134, 174308 (2011). 

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ISI 2012: 18- 22 June 2012 



THE MARINOAN 17 O-DEPLETION (MOSD) EVENT: SINGULARITY, 

SYNCHRONICITY, AND DURATION 

Huiming Bao, Department of Geology & Geophysics, Louisiana State University, Baton Rouge, LA 70803, 

U.S.A 

The “cap carbonates” overlying most of the globally distributed Marinoan (~635 Ma) glacial diamictites 

mark the ending of probably the most severe glaciation in Earth’s history. Among the many unusual 

geochemical features associated with this global glaciation, the most unexpected and puzzling one has been 

the non-mass-dependent 17 O depletion found in sulfate deposited during and after the glacial melt down 

period. Before this discovery, 17 O depletion was only expected for extraterrestrial materials, despite the fact 

that non-mass-dependent 17 O enrichment has been known to be possessed by compounds linked to ozone 

chemistry in terrestrial environments. The Marinoan 17 O-depletion (MOSD) event was suggested by us (Bao 

et al., 2008; 2009) to indicate most likely an ultra-high pCO 2 atmosphere, thus supporting the contentious 

“Snowball Earth” hypothesis. While there has been no direct evidence negating the proposed explanation, I 

am presenting new data that reveal a refined picture and research frontiers on the MOSD event. 

1. Singularity: Expanded sulfate data prior to 635 Ma upholds the singularity of this event in the past 3,600 

million years. There has been no effort in confirming the presence or absence of sulfate 17 O depletion 

associated with Paleoproterozoic (~2, 200 Ma) or Sturtian (~680 Ma) global glaciation. 

2. Synchronicty: An atmospheric cause of the MOSD event must predict a global synchronicity of the 

anomalous signals in rock record. There is a unified sedimentological sequence at both regional and global 

scales observed by many, e.g. Shields et al (2007) and Zhou et al (2010). The sequence has four distinct 

stages: 1) the ending of diamictite deposition; 2) the deposition of cap carbonates; 3) dissolution and 

disruption of the cap carbonates; and 4) transgression and the growth of the 17 O-depleted barite crystal fans. 

If there were a resolvable time delay in the depositional sequence from equatorial to higher latitude regions, 

we would expect to observe the onset of the 17 O anomaly in progressively older sequences in higher latitudes. 

So far, sulfate 17 O depletion has been reported in southern China, western Africa, Svalbard, and Western 

Australia. In the South China Block, 17 O-depleted barite occurs after the cap dolostones were disrupted by 

dissolution. In West Africa craton, the 17 O-depleted barite in cap dolostones appears to occur in exactly the 

same sequence as that in South China, “during late stages of the post-glacial marine transgression (Shields et 

al., 2007), although a study linking regional sedimentology, petrography, with the 17 O signal is lacking. In 

Svalbard, 17 O-depleted signal resides in carbonate-associated sulfate (CAS) in limestone lenses within the 

Wilsonbreen diamictite (Bao et al., 2009), while the occurrence of 17 O anomaly in its cap carbonates, the 

Dracoisen Formation, is unclear at this time. In Kimberley, Western Australia, 17 O-depleted signal is found 

in CAS in cap dolostones of the Moonlight Valley diamictite. The four cratons were situated at different 

latitudes at 635 Ma, ranging from ~25°N (South China), ~ 10°N (Kimberley), ~30°S (Svalbard), to ~45°S 

(West Africa) (Hoffman and Li, 2009). There is no correlation between the onset of 17 O anomaly in the 

depositional sequence and their paleo-latitudes, thus supporting a global synchronous meltdown of the 

Marinoan glaciation. 

3. Duration: The length of the MOSD event had to be determined by atmosphere-biosphere interactions. 

Before we proceed to model the many factors that were in play, however, geological constraints on the 

duration of this event are critical. One way to approach this problem is to see how far up in stratigraphic 

record the sulfate 17 O anomalous signal is still present. However, the problem is complicated by three 

immediate factors: 1) mixing with 17 O-normal sulfate in seawater, 2) microbial homogenization of 17 O 

signal; and 3) missing rock records. Thus, a lack of sulfate 17 O depletion for one sample or at one site does 

not necessarily indicate that the MOSD event was over. High-resolution lateral and vertical examination of 

sulfate 17 O signal must be conducted for multiple sections in a paleogeographically well-defined region. 

Initial data from South China Block suggest that the MOSD event probably persisted much longer than we 

thought (see Abstract by Killingsworth et al. for this conference). 

Page 21


ISI 2012: 18- 22 June 2012 



Ag 2 O: A new non-mass dependent standard material for oxygen isotope 

measurements 

Tesfaye Ayalneh Berhanu 1 , Joël Savarino 1 , Amaelle Landais 2 , Renato Winkler 2 , Thomas 

Röckmann 3 , Marion Früchtl 3 , Jan Kaiser 4 , Thomas Blunier 5 , Corentin Reutenauer 5 

1 Laboratoire de Glaciologie et Géophysique de l'Environnement Saint Martin d'Heres 

cedex, Grenoble, France (tayalneh@lgge.obs.ujf-grenoble.fr) 

2 Laboratoire des Sciences du Climat et de l'Environnement, Paris, France 

3 Institute for Marine and Atmospheric research Utrecht, Utrecht, The Netherlands 

4 University of East Anglia, School of Environmental Sciences, Norwich, UK 

5 Nils Bohr Institute, Centre for Ice and Climate, Kobenhavn, Denmark 

Since its birth as a field of science, isotope geochemistry has always faced the difficulty of 

finding the appropriate reference materials to fix its international scales. The stable isotopic 

composition of a given sample is reported with respect to a reference material taken as the 

origin of the scale by the relation δ (‰) = ((R sample /R ref )-1)×1000 where R is the least 

abundant to the most abundant isotope ratio for the sample (R sample ) and the reference (R ref ). 

There exist primary and secondary reference materials (PRM/SRM) certified by the IAEA or 

NIST for different isotopes. The formers define the origin of the scale such as the VSMOW 

or AIR-N 2 (i.e. δ 18 O (VSMOW) = 0‰ or δ 15 N (AIR-N 2 ) =0‰). However, the PRMs are 

valuable materials of finite quantity that may not always be in an appropriate chemical form 

for simple isotope standardization or they are not sufficient to fix the scale 

expansion/contraction of the analytical methods employed. The SRMs, anchored to the PRM, 

have been developed along the years to fill these gaps. With the recent expansion of the 

research on oxygen non mass-dependent fractionation and its associated effects, the need for a 

common, internationally recognized SRM has emerged. While USGS35 nitrate reference 

material has been characterized for its δ 18 O, δ 17 O and non-zero 17 O-excess, its chemical form 

limits strongly its use to the nitrogen cycles. To cross the borders between fields of research 

using 17 O-ecess as a tracer, it is necessary to produce in large quantity a new SRM which 

should be in a stable form, homogeneous, easy and safe to handle and transport, versatile in 

the way it can be used for calibration. As a first approach, it appears to us that Ag 2 O could 

have all these properties as it can readily produce O 2 , the ideal gas for oxygen standardization 

using IRMS instruments. 

We have prepared a solid Ag 2 O reference material with precisely known 17 O-excess by 

mixing AgNO 3 and NaOH in a 17 O enriched water via: 

Page 22 

2AgNO 3 + 2NaOH 2NaNO 3 + Ag 2 O+ H 2 O 

The Ag 2 O precipitate was extracted and washed many times to remove nitrate and excess 

NaOH. Then it was dried in an oven over night at 180°C. To determine the isotopic 

composition of the silver oxide, a small aliquot (≈ 100 micromoles) of silver oxide was 

transferred to the bottom of a pyrex quarter inch tube. At the top of the tube, Ascarite ® and 

magnesium percholarate were introduced to limit the transfer of CO 2 and water in the bellows 

of the IRMS during thermal decomposition of Ag 2 O at 530°C (Ag 2 O is known to adsorb air 

CO 2 in the presence of water). 

The pure O 2 gas obtained was analyzed on IRMS dual inlet mode for its isotopic composition. 

A highly reproducible result was measured in our laboratory. Similar Ag 2 O samples were sent 

to different labs to check inter laboratory reproducibility.


ISI 2012: 18- 22 June 2012 



TOP-DOWN AND BOTTOM-UP: THE ISOTOPIC COMPOSITION OF ATMOSPHERIC NITROUS 

OXIDE IN THE SOUTHERN HEMISPHERE SINCE 1940 

Kristie A. Boering 

Departments of Chemistry and of Earth and Planetary Science, University of California at 

Berkeley, Berkeley, CA 94720-1460 USA, boering@berkeley.edu 

Increases in atmospheric nitrous oxide since the Industrial Revolution are of concern given its 

importance as both a greenhouse gas and a precursor of nitrogen oxides that play an important role 

in the balance of ozone in the stratosphere. High-precision measurements of its mixing ratio at 

various monitoring stations at the surface are now being used in inverse models to help determine 

the magnitudes and geographic distributions of its sources, but important uncertainties remain, 

including the contribution of N 2 O-depleted air returning from the stratosphere. Measurements of 

the isotopic composition of atmospheric N 2 O (δ 15 N, site-specific δ 15 N, and δ 18 O) from firn air 

from Law Dome, Antarctica, from archived air samples from Cape Grim, Tasmania, and from 

whole air samples collected during NASA DC-8 and WB57-F aircraft missions out of Costa Rica 

in 2006-2007 will be presented which demonstrate that coherent temporal [Park et al., 2012] and 

spatial [Croteau et al., 2010] variations in isotopic compositions are detectable in the Southern 

Hemisphere and will ultimately aid in partitioning atmospheric variations in N 2 O into its various 

sources and sinks. Complementary laboratory microbial and field-scale measurements [Park et al., 

2011] will also be presented, with a view towards better coordinating "top down" versus "bottom 

up" approaches to quantifying and monitoring N 2 O sources. 

P. Croteau, E. L. Atlas, S. M. Schauffler, D. R. Blake, G. S. Diskin, and K. A. Boering, “The effect 

of local and regional sources on the isotopic composition of nitrous oxide in the tropical 

free troposphere and tropopause layer, ” J. Geophys. Res. (Atmospheres), 115, D00J11, 

doi:10.1029/2009JD013117, 2010. 

S. Park, T. Pérez, K. A. Boering, S. E. Trumbore, J. Gil, S Marquina, and S. C. Tyler, "Can N 2 O 

stable isotopes and isotopomers be useful tools to characterize sources and microbial 

pathways of N 2 O production and consumption in tropical soils?" Global 

Biogeochem.Cycles, 25, GB1001, doi:10.1029/2009GB003615, 2011. 

S. Park, P. Croteau, K. A. Boering, D.M. Etheridge, D. Ferretti, P. J. Fraser, K.-R. Kim, P.B. 

Krummel, R.L. Langenfelds, T.D. van Ommen, L.P. Steele, and C.M. Trudinger, "Trends 

and seasonal cycles in the isotopic composition of nitrous oxide since 1940," Nature 

Geoscience, 5, 261-265, doi:10/1038/NGEO1421, 2012. 

Page 23


ISI 2012: 18- 22 June 2012 



FREQUENCY STABILIZED CAVITY RINGDOWN FOR ISOTOPE RATIO MEASUREMENTS . 

Thinh Q. Bui 1 , David A. Long 2 , Joseph T. Hodges 2 , Charles E. Miller 3 , Mitchio Okumura 1 1 Thinh 

Bui novicebeing@gmail.com California Institute of Technology, Pasadena, CA 91125 2 National 

Institute Of Standards and Technology, Gaithersburg, MD 20899 3 Jet Propulsion Laboratory, 

Pasadena, CA 91109 

We demonstrate the performance of frequency-stabilized cavity ring-down spectroscopy (FS- 

CRDS) for the measurement of CO 2 isotope ratios. Carbon dioxide isotopic ratios were measured 

in the 1.6 µm wavelength region. We present CO 2 absorption spectra with peak signal-to-noise 

ratios as high as 28,000:1. Measured single-spectrum signal-to-noise ratios were as high as 8900:1, 

10,000:1, and 1700:1 for 13 C/ 12 C, 18 O/ 16 O, and 17 O/ 16 O, respectively. In addition, we show the 

importance of utilizing the Galatry line profile in the spectrum analysis. Despite the relatively low 

intensities of CO2 transitions near λ = 1.6 µm, the sensitivity and stability of FS-CRDS enabled 

measurement precision of pure CO 2 samples are competitive with other reported optical techniques 

performed in more favorable wavelength regions. These results indicate that a FS-CRDS 

spectrometer designed to probe CO 2 bands near wavelengths of 2.0 µm or 4.3 µm could achieve 

significantly improved precision over the present instrument and likely be competitive with mass 

spectrometric methods. 

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ISI 2012: 18- 22 June 2012 



WHY THERE ARE DISCREPANCIES BETWEEN THEORETICAL ESTIMATIONS AND 

EXPERIMENTAL RESULTS FOR THE EQUILIBRIUM THETA VALUE OF CO2-CEO2 EXCHANGE? 

Xiaobin Cao, Yun Liu * , Institute of Geochemistry, Chinese Academy of Sciences, Guiyang, China. 

*Corresponding author (liuyun@vip.gyig.ac.cn) 

With a growing interest in small 17 O-anomaly, there is a pressing need for the precise theta value (i.e. 

ln 17 α/ln 18 α), for a particular mass-dependent fractionation process (MDFP). Theta values could be 

determined by experiments (e.g., [1], [2] and [3]) or theoretical estimation ([4]). 

For the theoretical estimation, a method was proposed by us to calculate equilibrium theta values ([4]). 

Possible errors from calculation processes, such as the choice of theoretical levels, anharmonic effects, the 

choice of frequency scaling factors, clumped isotope effects and the rule of geometric mean approximation 

(RGM) were carefully checked in that study ([4]). We concluded that the carefully calculated theta values 

will be with the precision up to the third decimal number (i.e., 0.5xx). 

Hoffman et al. ([3]) suggested their experimental theta value was largely different from one of the theta 

values we predicted in ([4]). Here, we have carefully re-checked the calculation of equilibrium CO 2 -CeO 2 

exchange reaction and confirmed our previous calculations. The reasons of the discrepancy between their 

result and ours are given at below. 

Fig.1 Schematic presentation for the reason of why experimental theta for CO 2 -CeO 2 is 0.523 

Hoffman et al. ([3]) also pointed out that their much lower experimental theta value (i.e., 0.523 vs. 0.529) 

for CO 2 -CeO 2 might be caused by a thermal diffusion process. If we follow this idea, it could lead to a 

conclusion that the equilibrium 18 O fractionation factor between CO 2 and CeO 2 is 8.2 per mil at 685°C, 

which is very different from our calculated results (i.e., 11.9 per mil at 685°C). Also, the fractionation 

caused by diffusion is 3.5 per mil deduced from their experimental data, which is far from the value (i.e., 8.8 

per mil) for an ideal kinetic process. Figure 1 shows that their theta value is actually for a combined process 

and the theta value (here maybe lamda value is more precise for their case) is 0.523. Our theoretical 

estimation (0.529) is for the equilibrium CO 2 -CeO 2 exchange. There is a diffusion process from the surface 

of CeO2 (at 685°C) to the CO2 collecting place (at 25°C) which will have a completely different slope (e.g., 

0.509 as shown in Fig.1). Therefore, the observed theta value is actually the net result of equilibrium plus 

diffusion processes. If using the calculated equilibrium 18 O fractionation factor between CO 2 and CeO 2 at 

685°C and the theta value they determined by experiment, we can find out the theta value of that thermal 

diffusion process too. It is slightly different from 0.509 as shown in Fig.1. 

[1], Barkan and Luz (2005), RCMS. [2] Hofmann and Pack (2010) AC. [3] Hofmann et al. (2012) EPSL. 

[4] Cao and Liu (2011) GCA. 

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ISI 2012: 18- 22 June 2012 



ON THE MASS INDEPENDENT FRACTIONATIONS OF O, Hg, Si, Mg And Cd DURING OPEN- 

SYSTEM EVAPORATION OR THERMAL DECOMPOSITION. 

P. Cartigny 1 , J.M. Eiler 2 , P. Agrinier 1 , N. Assayag 1 . 1 Stable Isotope Laboratory, IPGP, France. 

cartigny@ipgp.fr. 2 Division of Geological and Planetary Sciences, California Institute of 

Technology, USA. 

Many experiments in which an element or a mineral is evaporated or thermally decomposed 

under vacuum are known to consistently display unexpected behaviors. These include too low rates of 

evaporation, smaller (i.e. closer to 1) than predicted fractionation factors, and an inconsistent behavior 

of the stable isotope ratios of a given element (i.e. mass-independent fractionation). This applies to 

many elements including O, Hg, Si, Mg and Cd. 

Many suggestions have been proposed from the existence of unknown types radicals, evidence for new 

isotope effect(s) and, sometimes, an isotope re-equilibration. 

We present interpretations for a series of earlier observations, including experiments by Miller et al. 

(2002) in which mass-independent O isotope fractionations are produced during thermal decomposition 

of carbonates [1], and the finding of Estrade et al. (2009) showing an unexpected slope in a plot of 

∆ 199 Hg vs ∆ 201 Hg (close to 1.2 instead of 2.4) during open-system evaporation of Hg [2], the isotopes 

anomalies associated with the evaporation of cadmium Cadmium [3] and the O, Si and Mg isotope 

anomalies described by Davies et al. (1990) during in-vacuo evaporation of forsterite. 

These and related results can be explained if a fraction (usually a few to several tens of 

percent) of the evaporated compounds indeed forms (or re-equilibrate) under conditions of isotope 

equilibrium, the remaining fraction obeying kinetic fractionation of its stable isotopes. This is the 

mixing that results in the appearance of mass-independence, rather than the action of a novel isotope 

effect having non-cannonical mass law as illustrated by the following figure. 

[1]Miller et al. (2002) PNAS vol. 99, p 10988–10993. [2] Estrade et al. (2009) Geochim. Cosmochim. Acta vol. 73, p 

2693- 2711. [3] Wombacher et al. (2004) Geochim. Cosmochim. Acta vol. 68, p 2349-2357 [4] Davies et al. (1990) 

Nature vol. 347, p 655-658. 

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ISI 2012: 18- 22 June 2012 



OBSERVATION OF MASS-INDEPENDENT OXYGEN ISOTOPIC FRACTIONATION 

IN SOLID SILICATES THROUGH GAS PHASE REACTION: COSMOCHEMICAL 

IMPLICATIONS. 

Subrata Chakraborty 1 , Petia Yanchulova 1 and M. H. Thiemens 1 

1 University of California, San Diego, Department of Chemistry and Biochemistry, 9500 Gilman 

Drive, La Jolla, CA 92093-0356 (subrata@ucsd.edu) 

Introduction: A wide range of oxygen isotopic compositions are observed in meteorites, 

possibly reflecting heterogeneity in the solar nebula. A striking feature is the departure from the 

terrestrial mass fractionation line (TFL). The oxygen isotopic composition of meteoritic material 

reveals that different groups lie on lines of differing slope values distinct from the TFL [1-3]. 

Photo-chemical isotopic self-shielding of nebular CO has been proposed as a mechanism to 

produce the CAI line (slope one line) [4-7]. Experimentally measured oxygen isotopic 

fractionation data for CO photodissociation yields a wavelength dependent fractionation trend 

and is not totally supportive of isotope self-shielding as a mechanism for generating a reservoir 

with equal 17 O and 18 O enrichment [8-9]. Consequently exploration of alternative mechanisms is 

warranted. Irrespective of the source, the mechanism must be known by which the anomalous 

oxygen is incorporated into meteoritic material and produces meteoritic bulk isotopic 

compositions. In this abstract, we describe experiments of the oxidation reaction of SiO to form 

SiO x in the gas-phase and present isotope results from the gas- and solid-phase products and 

reactants. 

Experimental: Ultra high pure SiO nuggets (~ 2-4 mm in size) were 

vaporized inside a vacuum chamber by an Excimer laser beam (248 nm) 

in two different ways for two different sets of experiments: (a) in the 

presence of a well-known amount of ultra high purity oxygen (of known 

isotopic composition) and (b) in the presence of a mixture of oxygen and 

hydrogen in varied proportions. During the vaporization process solid 

oxides (SiO x ) were formed throughout the chamber, indicating gas-phase 

reaction in the laser-induced hot (~ 2000 o C) plume as shown in Figure 1. 

Results and Discussion: The oxygen isotopic composition of solid 

SiO x (mostly glass) was measured by CO 2 -laser fluorination 

technique and the oxygen isotopic compositions of residual 

oxygen was also measured and shown in Figure 2. The 

measured oxygen isotopic composition of solid SiO x and the 

residual oxygen were mass-dependently fractionated in the 

set (b) experiments, where as the compositions are massdependent 

in the set (a) experiments. This is the first 

observation of mass independently fractionated oxygen 

isotopic composition in solid silicates formed through gasphase 

reactions and this discovery has a great implication in 

understanding the oxygen isotopic distributions in different 

meteorite groups. The results will be discussed in detail in 

the conference along with the cosmochemical implications. 

References: [1] Clayton R. N. (1993) Annual Review of 

Earth and Planetary Sciences, 21, 115-149. [2] Clayton R. 

17 O (‰) 

20 

15 

10 

5 

0 

-5 

-10 

-15 

SiOx 

(with H2) 

Initial SiO 

SiOx 

(with H2) 

Figure 1. SEM image of 

product SiO x (in 

presence of H 2 ). 

Standard: NBS-28 

Initial O2 

-30 -20 -10 0 10 20 30 40 50 

18 O (‰) 

Residual O2 

(without H2) 

Product-SiOx (Over Window with 

hydrogen expt) 

Product-SiOx (Over Al Foil-with 

hydrogen expt) 

SiOx (Without hydrogen 

experment) 

Residual O2 

(with H2) 

Figure 2. Three isotope oxygen plot of 

product SiO x and residual oxygen. 

N. et al. (1973) Science, 182, 485-488. [3] Thiemens M. H. (2006) Annual Review of Earth and 

Planetary Sciences, 34, 217-262. [4] Clayton R. N. (2002) Nature, 415, 860-861. [5] Yurimoto H. 

and Kuramoto K. (2004) Science, 305, 1763-1766. [6] Greenwood J. P. et al. (2011) Nature 

Geosci, 4, 79-82. [7] Lyons J. R. and Young E. D. (2005) Nature, 435, 317-320. [8] Chakraborty 

S. et al. (2008) Science, 321, 1328-1331. [9] Chakraborty S. et al. (2009) Science, 324, 4. 

Page 27


ISI 2012: 18- 22 June 2012 



UNUSUAL FRACTIONATION OF BOTH ODD AND EVEN MERCURY ISOTOPES IN PRECIPITATION FROM 

PETERBOROUGH, ONTARIO, CANADA 

Jiubin Chen 1,2 *, Holger Hintelmann 2 , Brian Dimock 2 and Xinbin Feng 1 , 1. Institute of 

Geochemistry, CAS, 46 Guanshui Road, Guiyang, GuiZhou 550002, China., 2. Chemistry 

Department, Trent University, Peterborough, Ontario, K9J7B8, Canada., 

*chenjiubin@vip.gyig.ac.cn 

Preliminary studies have demonstrated both mass-dependent fractionation (MDF) and massindependent 

fractionation (MIF) of Hg isotopes in the environment and the potential for their 

application in biochemistry and geochemistry (1,2). Though atmospheric deposition is a primary 

pathway by which Hg enters earth surface ecosystem, little has been reported on Hg isotopes in 

precipitation. Laboratory experiments and measurements of Hg accumulated in lichens predicted 

negative MIF of odd Hg isotopes ( 199 Hg, 201 Hg) in the atmosphere. However, recent studies 

showed positive MIF of odd Hg isotopes in both precipitation and ambient air and reported, 

unexpectively, positive MIF of even-mass Hg isotope ( 200 Hg) in precipitation (3,4). 

In order to examine Hg isotopic composition in precipitation, 19 rainwater and 4 snow samples 

were collected in Peterborough (Ontario, Canada) in 2010. Hg isotopic compositions were 

determined after Hg pre-concentration using a method developed by Chen et al. (2010). All 

precipitation samples displayed significant MDF (δ 202 Hg between -0.02‰ and -1.48‰) and MIF 

of odd isotopes (Δ 199 Hg varying from -0.29‰ to 1.13‰). We also report for the first time a 

seasonal variation of MIF of even Hg isotopes (Δ 200 Hg) in wet precipitation. Our results may 

suggest that photoreduction in droplets or on the surface layer of snow crystals induce odd Hg 

isotope anomalies, while mass independent fractionation of 200 Hg is probably triggered by photoinitiated 

oxidation occurring on aerosol or solid surfaces in the tropopause. The observed seasonal 

variation of even Hg isotope MIF (Δ 200 Hg decrease with ambient temperature) is possibly a 

powerful tool for meteorological research and may aid in monitoring related climate changes. 

More research is required to fully understand the behavior of Hg isotopes in the atmosphere. 

1) Bergquist, B. A.; Blum, J. D. Sci. 2007, 318, 417-420. 2) Gantner, N.; Hintelmann, H.; Zheng, 

W.; Muir, D. C. EST 2009, 43, 9148-9154. 3) Gratz et al., EST 2010, 44, 7764-7770. 4) Sherman 

et al., EST 2012, 46, 382-390. 5) Chen et al., JAAS, 2010, 25, 1402-1409. 

Page 28


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ULTRAVIOLET SPECTROSCOPY OF 32 S, 33 S, 34 S AND 36 S SULPHUR DIOXIDE: 

FRACTIONATION BY PHOTOEXCITATION 

S. O. Danielache 1 , S. Hattori 2 , M. S. Johnson 3 , Y. Ueno 1 , S. Nanbu 4 , and N. Yoshida 2 

1 Department of Earth and Planetary Science, Tokyo Institute of Technology, Tokyo, Japan 

sebas@depe.titech.ac.jp 2 Department of Environmental Science and Technology, Tokyo 

Institute of Technology, Yokohama, Japan 3 Department of Chemistry, University of 

Copenhagen, Copenhagen, Denmark, 4 Sophia University, Faculty of Science & 

Technology, Tokyo, Japan 

We present a model study of the non-mass dependent (NMD) fractionation produced 

during the photochemical oxidation involving the SO 2 * molecule. For this study we used a 

recently reported spectra of the ultraviolet absorption cross sections of the 32 SO 2 , 33 SO 2 , 

34 SO 2 and 36 SO 2 isotopologues recorded between 40,000 and 30,300 cm -1 (250 to 330 nm) 

at 293 K with a resolution of 8 cm -1 and previously reported spectra recorded at 25 cm -1 . 

The B 1 B 1 -X 1 A 1 band absorbs UV light below the dissociation threshold and therefore 

produce a photoexited molecule denoted SO 2 *. The fate of the trapped extra energy within 

this molecule is a combination of luminescence, internal energy conversion and energy 

transfer by collision with surrounding molecules. Given suitable broadband or single 

wavelength photolysis conditions NMD distribution of 32/33/34/36 SO 2 * isotopologues is 

generated and given suitable conditions this signal is preserved in reaction products. We 

present the results of a model study compared them to several chamber experiments. We 

conclude that planetary atmospheres will exhibit isotopic fractionation from both 

photoexcitation and photodissociation, and that experiments in the literature have isotopic 

imprints arising from both the B 1 B 1 -X 1 A 1 and the C 1 B 1 -X 1 A 1 bands. 

Page 29


ISI 2012: 18- 22 June 2012 



OZONE FORMATION ON COLD SURFACES: COSMOCHEMICAL IMPLICATIONS 

Gerardo Dominguez 1 , Terri Jackson 2 , Morgan Nunn 2 , Dimitri Basov 3 , Mark Thiemens 2 1 California 

State University, San Marcos, Department of Physics 2 University of 

California, San Diego, Department of Chemistry and Biochemistry 3 University of California, San 

Diego, Department of Physics 

Perhaps one of the most dramatic examples of a natural system with a mass-independent distribution of 

isotopes is the solar system. Recent measurements by NASA’s Genesis mission have confirmed earlier 

suspicions that the Sun is enriched in 16 O compared to the rest of the solar system(1). This distribution 

of oxygen isotopes remains unexplained, although models have previously been proposed to explain 

the observations of mass-independently fractionated oxygen reservoirs in the solar system (2). These 

include supernova injections of 16 O and photochemical self-shielding of CO and O 2 (3-5). While some 

of these models have been discarded, self-shielding of CO appears to be the most favored explanation 

to date even though simple chemical reactions have not been ruled out as a mechanism. 

Recently, it was suggested that the formation of molecular cloud H 2 O on interstellar dust grains found 

in cold-dense molecular clouds (DMCs), the regions of space where start formation is observed to 

occur, may produce mass-independently enriched water via precursors such as HO 2 and O 3 (6). The 

focus on H 2 O and its precursors is significant because astrochemical models of indicate that up to 60% 

of the “volatile” oxygen in dense molecular clouds, that is oxygen not associated with silicates dust (~ 

30% of all O), may end up as H 2 O. Therefore, understanding the isotopic fractionation associated with 

the formation of H 2 O in cold dense molecular clouds may help to explain the anomalous distribution of 

oxygen in the solar system. Here, we present preliminary results on the isotopic fractionation 

associated with the formation of ozone (O 3 ) on cold (T~32 K) interstellar dust grain-like surfaces. 

To produce O 3 on a cold surface, O 2 ices were deposited on a cold stainless steel surface attached to the 

cold head of a liquid helium-cooled cryostat. Approximately 200 micromoles were deposited in the 

experiments reported. UV photolysis of these O 2 ices was achieved through the use of an Opthos 

microwave powered Hg lamp (l=185.4 nm, F~10 16 s -1 ). O 3 and O 2 were separated cryogenically and 

the O 3 was collected on molecular sieve following standard procedures and the triple-oxygen isotopic 

composition of this O 3 was determined using a MAT 253 IRMS. We find that O 3 produced from the 

photolysis of O 2 ices is mass-independently fractionated with a δ 17 O/δ 18 O~ 1. These results have 

potentially significant astrophysical and cosmochemical implications and these will be discussed along 

with updated experimental results of O 3 formation at different temperatures. 

1. McKeegan KD, Kallio APA, Heber VS, Jarzebinski G, Mao PH, et al. 2011. The Oxygen Isotopic Composition of the 

Sun Inferred from Captured Solar Wind. Science 332:1528-32 

2. Clayton RN, Grossman L, Mayeda TK. 1973. A Component of Primitive Nuclear Composition in Carbonaceous 

Meteorites. Science 182:485-8 

3. Thiemens MH, Heidenreich JE, III. 1983. The mass-independent fractionation of oxygen - A novel isotope effect and 

its possible cosmochemical implications. Science 219:1073-5 

4. Clayton RN. 2002. Solar System: Self-shielding in the solar nebula. Nature 415:860-1 

5. Lyons JR, Young ED. 2005. CO self-shielding as the origin of oxygen isotope anomalies in the early solar nebula. 

Nature 435:317-20 

6. Dominguez G. 2010. A Heterogeneous Chemical Origin for the 16 O-enriched and 16 O-depleted Reservoirs of the Early 

Solar System. The Astrophysical Journal Letters 713:L59-L63 

Page 30


ISI 2012: 18- 22 June 2012 



DETERMINING THE ISOTOPIC ANATOMY OF COMPLEX MOLECULES USING HIGH-RESOLUTION, 

MULTI-COLLECTOR GAS SOURCE MASS SPECTROMETRY 

John Eiler 1 , Matthieu Clog 1 , Paul Magyar 1 , Alison Piasecki 1 , Alex Sessions 1 , Daniel Stolper 1 

1 California Institute of Technology, Pasadena, CA, eiler@gps.caltech.edu 

Molecules composed of common volatile elements (e.g., H, C, N, O, S, Cl, etc.) are mixtures of 

isotopologues that differ in their number and, in some cases, sites of rare isotope substitutions. 

Non-symmetric molecules (like many organic molecules) often have large numbers of 

isotopologues: for example formic acid (HCOOH) has 72 distinct isotopologues. Larger lipids 

(e.g. alkanes) or sugars, for example, can have many thousands or millions of isotopologues. 

These isotopologues all have distinct physical and chemical properties that have the potential to 

serve as signatures of source, reaction mechanisms and environmental conditions. 

The information contained in the isotopic anatomy of molecules is generally lost when using 

common isotopic analysis methods. These techniques often rely on combustion or pyrolysis to 

decompose analytes to simple molecules, and allow one to determine only the overall inventory 

of rare isotopes in a sample (e.g., the 13 C/ 12 C ratio) irrespective of site-specific isotopic 

differences or extents of multiple substitution. Methods which attempt to recover information on 

intramolecular isotopic anatomies include: natural-abundance NMR analysis of site-specific 13 C 

and D abundances in organic molecules; position-specific mass spectrometric analysis of 15 N in 

N 2 O; ‘clumped’ isotope analysis of multiply-substituted CO 2 and O 2 (e.g., 13 C 18 O 16 O); and the 

several previous efforts to extract site-specific isotopic compositions through controlled chemical 

degradation of complex molecular or mineral structures followed by conventional isotopic 

analysis of the products. These techniques have demonstrated uses, but each is relatively 

specialized and few have developed into widely applied and well-explored tools. 

We present an approach to this problem based on high-resolution, multi-collector gas source mass 

spectrometry of volatile and semi-volatile molecules. We explore this approach using the ‘253- 

Ultra’ — a prototype double-focusing isotope ratio mass spectrometer constructed by Thermo- 

Fischer and installed in the Caltech laboratories for stable isotope geochemistry in Dec. 2011. 

This instrument achieves mass resolving power of up to 26,000 (M/∆M, 5%, 95 % definition) and 

can analyze diverse gases and semi-volatile compounds (i.e., using a conventional dual inlet 

and/or a carrier gas). It has a multi-collector array comprised of 7 detector positions, all of which 

can be moved relative to one another and any one of which can register ions through an SEM or 

faraday collector, spanning up to a 10 13 range in signal strength. Abundance sensitivity is as good 

as 10 -12 , and precisions are commonly counting statistics limited down to levels of 0.01 ‰ (or 

better) for a wide range of species. This instrument permits resolution of many isobaric 

interferences, enabling direct isotopic analysis of molecules having complex mass spectra (e.g., 

hydrocarbons). Although mass spectrometry generally cannot directly distinguish isotopomers, 

this instrument can be used to reconstruct position-specific isotopic compositions (including 

multiple substitutions) by comparing isotopic compositions of full molecular ions with those of 

fragment ions. I.e., in a fashion analogous to the established methodologies behind position 

specific 15 N analyses of N 2 O, but generalized to the many fragment ions typically created by 

electron bombardment of organics. We illustrate the capabilities of this instrument through 

representative applications focused on: singly and multiply substituted H 2 , O 2 , CH 4 and C 2 H 6 ; 

position-specific 13 C analysis of C 3 H 8 ; precise analysis of 17 O/ 16 O and 18 O/ 16 O on fragment O ions 

from CO 2 and other gases; a variety of N 2 O isotopologues (including 18 O, 17 O, position specific 

15 N, and various ‘clumped’ species); and high-precision and abundance sensitivity noble gas 

analyses. These capabilities greatly extend the scope of stable isotope constraints that can be 

brought to bear on problems in forensics, environmental geochemistry, biochemistry, and earth 

and planetary sciences. 

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ISI 2012: 18- 22 June 2012 



AN ISOTOPE VIEW ON IONISING RADIATION AS A SOURCE OF SULPHURIC ACID 

Martin B. Enghoff 1 , Nicolai Bork 1,2 , Shohei Hattori 3 , Carl Meusinger 4 , Mayuko 

Nakagawa 5 , Jens Olaf Pepke Pedersen 1 , Sebastian Danielache 3,6 , Yuichiro 

Ueno 6 , Matthew S. Johnson 4 , Naohiro Yoshida 3,5 , and Henrik Svensmark 1 1 National Space Institute, 

Technical University of Denmark, 2100, Copenhagen Ø, Denmark 2 Division of Atmospheric Science, 

Department of Physics, P.O. Box 64, 00014 University of Helsinki, Finland 3 Department of Environmental 

Science and Technology, Interdisciplinary Graduate School of Science and Engineering, Tokyo Institute of 

Technology, Yokohama, 226-8502, Japan 4 University of Copenhagen, Department of Chemistry, 2100, 

Copenhagen Ø, Denmark 5 Department of Environmental Chemistry and 

Engineering, Interdisciplinary Graduate School of Science and Engineering, Tokyo Institute of Technology, 

Yokohama, 226-8502, Japan 6 Department of Earth and Planetary Science, Tokyo Institute of Technology, 

Meguro-ku,Tokyo, 152-8551, Japan 

A NEW 

Sulphuric acid is an important factor in aerosol nucleation and growth. It has been shown that ions 

enhance the formation of sulphuric acid aerosols, but the exact mechanism remains undetermined. 

Furthermore some studies have found a deficiency in the sulphuric acid budget, suggesting a missing 

source. In this study the production of sulphuric acid from SO 2 through a number of different pathways 

is investigated. The production methods are standard gas phase oxidation by OH radicals produced by 

ozone photolysis with UV light, liquid phase oxidation by ozone, and gas phase oxidation initiated by 

gamma rays. The distributions of stable sulphur isotopes in the products and substrate were measured 

using isotope ratio mass spectrometry. All methods produced sulphate enriched in 34 S and we find a 

δ 34 S value of 8.7 ± 0.4 ‰ (1 standard deviation) for the UV-initiated OH reaction. Only UV light (Hg 

emission at 253.65 nm) produced a clear non-mass-dependent excess of 33 S. The pattern of isotopic 

enrichment produced by gamma rays is similar, but not equal, to that produced by aqueous oxidation of 

SO 2 by ozone. This, combined with the relative yields of the experiments, suggests a mechanism in 

which ionizing radiation may lead to hydrated ion clusters that serve as nanoreactors for S(IV) to S(VI) 

conversion. 

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ISI 2012: 18- 22 June 2012 



MODEL FOR NITROUS OXIDE ISOTOPOMER FORMATION FROM NITROXYL (HNO) 

DIMERIZATION IN AQUEOUS SOLUTION 

Carsten Fehling 1 and Gernot Friedrichs 2. 1 Department of Oceanography, Dalhousie University, 

Halifax, Canada fehling@phc.uni-kiel.de 2 Institut für Physikalische Chemie, Christian- 

Albrechts-Universität zu Kiel, Germany 

The 15 N-site preference of nitrous oxide, the ratio of the isotopomers 14 N 15 N 16 O and 15 N 14 N 16 O, is 

considered to be a selective proxy for the formation mechanism of this important trace gas, which 

influences the climate system due to radiative forcing in the troposphere and ozone depletion in 

the stratosphere. Significantly different isotopomer ratios have been reported for nitrous oxide 

from chemical formation reactions compared to enzyme catalyzed pathways, e.g. from fungi and 

bacteria. However, the origin of the underlying isotopomer effect on the molecular scale has rarely 

been analyzed in detail and the assignment of the intermediates, leading to isotopic discrimination, 

often remained speculative [1]. 

Among the chemical nitrous oxide forming reactions, the dimerization of nitroxyl (HNO) is 

discussed as an important source reaction observed in the gas phase and in aqueous solution. The 

corresponding reaction rate in solution has recently been reassessed in the new light of the 

previously unconsidered complex spin equilibrium of nitroxyl [2], but certain experimental results 

remained still inconsistent with the suggested mechanisms. In order to gain deeper insight into the 

underlying mechanism and its relevance for N 2 O isotopomer formation, detailed DFT based 

calculations of the possible intermediate species have been undertaken. Based on the calculated 

acid-base equilibria and estimated rate constants a new mechanism for this complex reaction has 

been worked out, consistent with experimental studies [3]. 

Isotopomer ratios of nitrous oxide from HNO dimerization were experimentally studied using a cw 

CRDS based technique and were in good agreement with previous IRMS measurements [1]. These 

results pointed towards a pronounced experimental isotopomer effect favoring 14 N 15 N 16 O 

formation. In addition, the kinetics and related isotope effects of the derived reaction sequence for 

nitrous oxide formation from this mechanism have been analyzed to derive theoretical N 2 O 

isotopomer ratios. These theoretical predictions from a simple kinetic model agreed well with the 

experimental results and were able to explain the quite constant 15 N-site preference found under 

various reaction conditions. The possible relevance of the here dominating intermediates for 

enzyme catalyzed nitrous oxide formation mechanisms will be discussed. 

[1] S. Toyoda, H. Mutobe, H. Yamagishi, N. Yoshida, Y. Tanji, Soil Biol. Biochem. 2005, 37, 

1535–1545. 

[2] K. M. Miranda, Coord. Chem. Rev. 2005, 249, 433 – 455. 

[3] C. Fehling and G. Friedrichs, J. Am. Chem. Soc. 2011, 133, 17912-17922. 

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D/H FRACTIONATION BETWEEN C-H SPECIES IN CRUSTAL FLUIDS: AN IN-SITU 

EXPERIMENTAL STUDY 

Dionysis I. Foustoukos and Bjorn O. Mysen, dfoustoukos@ciw.edu Geophysical Laboratory, Carnegie 

Institution of Washington, Washington, DC 20015, USA 

Characterization of the processes that govern the behavior, budget and recycling of C-H volatiles in the 

Earth’s interior is fundamental to our understanding of the formation and evolution of the solid Earth, its 

oceans, and atmosphere. Most importantly, the partitioning and speciation changes of volatiles coexisting 

with supercritical fluids could induce significant stable isotope fractionation effects at conditions that 

existing models cannot constrain. 

To describe the thermodynamics of the exchange reactions between the different D-H isotopologues of 

H 2 and CH 4 under supercritical water conditions, a novel experimental technique has been developed by 

combining vibrational Raman spectroscopy with hydrothermal diamond anvil cell experimental designs 

(HDAC), which offers a method to determine the in-situ evolution of D-H containing species. For example, 

in a recently published experimental study, we investigated the hydrogen-deuterium exchange between 

dissolved H 2 and supercritical water at temperatures ranging from 300 – 800 o C and pressures ~ 0.3 – 1.3 

GPa [1]. Experimental results obtained in-situ and on quenched samples revealed an enthalpy of -3.4 

kcal/mol for the H 2(aq) -D 2(aq) disproportionation reaction. These estimates, however, differ significantly from 

those predicted for the exchange reaction in the gas phase by statistical mechanics models (+0.16 kcal/mol). 

Thus, the presence of water appears to affect the distribution of H- and D-bearing species with important 

implications for our understanding of stable 

hydrogen isotope fractionation between C-H 

volatiles within the Earth’s crust and upper 

mantle. 

Here, we present a series of HDAC 

experiments conducted at 400 – 800 o C, 0.5 – 

1GPa involving the H 2 -CH 4 -H 2 O-D 2 O system in 

both the supercritical water and gaseous phase. In 

detail, tetrakis silane (Si 5 C 12 H 36 ) was reacted with 

H 2 O-D 2 O aqueous solution in the presence of Ni 

and Pt metal catalyst, resulting to the formation of 

volatiles such as H 2 , D 2 , HD, CH 4 , CH 3 D, CHD 3 , 

CH 2 D 2 and CD 4 . For the gas phase experiments, 

the initial abundance of reactants (tetrakissilane:fluid) 

was adjusted to facilitate H 2 O 

removal through SiO 2 precipitation. By 

measuring the relative intensities of Raman 

vibrational modes of species over a range of 

temperatures and pressures, we determined the 

thermodynamic properties of the different isotope 

exchange reactions between the H-D methane 

isotopologues (e.g. CD 4 + 3CH 4 = 4CH 3 D). 

Experimental results illustrate the distinct 

Figure 1. Raman spectra of a quenched sample after reacting 

D2O-‐‐H2O aqueous solution with tetrakis silane. The 

equilibria relationships among the D-‐‐H methane 

isotopologues appear to be different for systems involving 

either gas or liquid water phase. Results support the 

important role of H2O on the D/H fractionation between C-‐‐ 

H species at high temperature and pressure. 

difference on the distribution of methane isotopologues between the gas and liquid-water-bearing systems 

(Fig. 1), and thus, underline the role of supercritical water on the solubility of the hydrogen-bearing volatiles. 

1. Foustoukos D.I. and B.O. Mysen, (2012) D/H isotopic fractionation in the H 2 -H 2 O system at supercritical 

water conditions: Composition and hydrogen bonding effects, Geochimica et Cosmochimica Acta, doi: 

10.1016/j.gca.2012.03.003. 

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PARTIAL INTRAMOLECULAR 13 C ISOTOPE DISTRIBUTION IN LONG-CHAIN N-ALKANES (C 11 - 

C 31 ) DETERMINED BY ISOTOPIC 13 C NMR 

Alexis Gilbert 1 , Keita Yamada 1 , Naohiro Yoshida 1 

1 Interdisciplinary Graduate School of Science and Engineering, Tokyo Institute of Technology, 

gilbert.a.aa@m.titech.ac.jp 

n-Alkanes are ubiquitous compounds biosynthesized in several matrices such as terrestrial and 

aquatic plants, algae and insects. The 13 C isotopic composition (noted as d 13 C and expressed in ‰ 

relative to the international standard, Pee Dee Belemnite) of n-alkanes biosynthesized by those 

organisms is therefore a useful indicator to infer their origin in sediments or petroleum (Hayes, 

1993). 

The isotope composition d 13 C of alkanes is usually determined using Gas Chromatography 

coupled with Isotope Ratio Mass Spectrometry of the CO 2 formed by combustion of the elutants 

(GC-C-IRMS). This approach leads to the determination of the isotope composition of these 

molecules at the molecular level since all the carbons of the molecule are converted to CO 2 . Yet, it 

is well recognized that the determination of the d 13 C at the intramolecular level, i.e. on each carbon 

position of the molecule, allows an important gain of information (Hayes, 2001). 

Here we examine the feasibility to determine the intramolecular isotope distribution of long-chain 

n-alkanes (C 11 -C 31 ) using isotopic 13 C NMR (Caytan et al., 2007). The relative 13 C abundance of 

the three terminal carbon atom positions can be determined within a 1.2‰ precision. Although the 

information obtained is only partial, intramolecular isotope differences up to 15‰ within the same 

compound can be observed. Data obtained on n-alkanes from commercial sources show that (i) the 

intramolecular 13 C pattern is alternate between odd and even carbon-numbered n-alkanes in the 

C 17 -C 29 range and (ii) the C 11 -C 15 n-alkanes can be distinguished from the heavier ones from their 

intramolecular 13 C isotopic pattern. Those preliminary results clearly show the potentiality of 

isotopic 13 C NMR in the biogeochemistry field. 

Caytan, E., Botosoa, E.P., Silvestre, V., Robins, R.J., Akoka, S., Remaud, G.S., (2007) Accurate 

Quantitative 13 C NMR Spectroscopy: Repeatability over Time of Site-Specific 13 C Isotope 

Ratio Determination. Analytical Chemistry, 79(21), 8266-8269. 

Hayes, J.M., (1993) Factors controlling 13C contents of sedimentary organic compounds: 

Principles and evidence. Marine Geology, 113, 111. 

Hayes, J.M., (2001) Fractionation of Carbon and Hydrogen Isotopes in Biosynthetic Processes. 

Reviews in Mineralogy and Geochemistry, 43(1), 225-277. 

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δ 13 C MEASUREMENT OF CERAMIDE BY A GAS CHROMATOGRAPHY-COMBUSTION-IRMS AS A 

TRACER FOR CLARIFYING THE MOISTURIZING EFFECT IN SKIN 

Hiroyuki Haraguchi 1, 2 , Keita Yamada 2 , Rumiko Miyashita 1 , Kazuhiko Aida 1 , Masao Ohnishi 3 , 

Naohiro Yoshida 2 

1 Central Laboratory, Nippon Flour Mills Co., Ltd., 5-1-3 Midorigaoka, Atsugi, Kanagawa 243- 

0041, Japan, e-mail: haraguchi@fasmac.co.jp. 2 Department of Environmental Chemistry and 

Engineering, Interdisciplinary Graduate School of Science and Engineering, Tokyo Institute of 

Technology, 4259 Nagatsuta, Yokohama, Kanagawa 226-8502, Japan . 3 Department of Food 

Science, Obihiro University of Agriculture and Veterinary Medicine, Inadacho, Obihiro, 

Hokkaido 080-8555, Japan 

Cermide (Cer) and glucosylceramide (GlcCer) are one of sphingolipids and found in a wide 

variety of organisms. Cer is known to play critical roles in the cutaneous barrier function, waterholding 

capacity of the skin, etc. A dietary intake of GlcCer is known to improve the skin 

moisturizing effects in the skin 1), 2) . But it has not been clarified how a dietary intake of GlcCer 

acts Cer in skin and results in the moisturizing of a skin. We are trying to find the moisturizing 

effect of GlcCer in skin using the carbon stable isotope ratio (δ 13 C) as a tracer of GlcCer and Cer 

in skin. The content of Cer in a skin is very small (< 10 2 mg/mg dry stratum corneum), so it is 

necessary to use a gas chromatography-combustion-IRMS (GC-C-IRMS) for δ 13 C measurement. 

In this sturdy, we determined the conditions of δ 13 C measurement of Cer by a GC-C-IRMS using 

Synthesized Cer (SCer). 

SCer (CerII, IIIb, III and VI) were derivertized to tri-methylsilylated SCer (TMS-SCer) with N- 

trimethylsilylimidazole (TMSI) at 70°C over 30min. The yield of each TMS-SCer was about 90%, 

and proportion to the amount of SCer (15-200mg). The residue of TMSI in TMS reaction solution 

had to be completely removed by hexane-water distribution because TMSI residue in TMS-SCer 

caused a clogging of the flow line during δ 13 C measurement by a GC-C-IRMS. δ 13 C measurement 

for each SCer by a GC-C-IRMS had high repeatability (Standard deviation < 0.3‰), and each δ 13 C 

after the correction of TMS was no independence in amounts of TMSI. But each δ 13 C was lower 

than that by a sealed tube combustion method. Although the difference between both methods for 

each SCer depended on δ 13 C of TMSI, the difference was correlation to the number of hydroxyl 

group within SCer to be derivertized by TMSI. Therefore, it should be take account of the number 

of hydroxyl group within Cer to obtain δ 13 C of Cer in a skin. 

Keywords: ceramide, moisturizing effect, carbon isotope ratio, gas chromatography –combustionisotope 

ratio mass spectrometry (GC-C-IRMS) 

References 

1) Asai, S., Miyachi, H., Rinsho Byori, 55, 209-215 (2007). 

2) Ishikawa, J., et al., J. Dermatol. Sci., 56, 205-218 (2009). 

Page 36


ISI 2012: 18- 22 June 2012 



MAGNETIC ISOTOPE EFFECTS AS AN EXPLANATION FOR 33 S ANOMALIES IN TSR REACTIONS. 

Harry Oduro 1 , Brian Harms 2 , Herman O. Sintim, Alan J. Kaufman, George Cody and James 

Farquhar 2 . 1 Department of Earth, Atmospheric and Planetary Sciences, Massachusetts Institute of 

Technology, Cambridge, MA USA (hoduro@mit.edu) 

2 Department of Geology, University of Maryland, College Park, MD USA (bharms@umd.edu) 

A recent study by Watanabe et al (2009, Science) found that laboratory reactions of sulfate with 

simple amino acids produced 33 S and 36 S anomalies, raising the question that some sulfur isotope 

anomalies in Archean rocks might represent diagenetic, post-sedimentation reactions rather than 

primary, atmospheric photolysis reactions. Here we report an attempt to replicate the results of the 

previous study, and an attempt to better understand the mechanisms responsible for the observed 

sulfur isotope anomalies (Oduro et al., 2011; PNAS). Our experimental results show large 33 S 

enrichments (up to +13 per mil), beyond what would be expected from classical (mass-dependant) 

isotope effects -- but only in the polysuflide fraction. In contrast, the 36 S enrichments that we 

observe can be explained by a combination of classical isotope effects and mixing. We therefore 

propose that the large 33 S enrichments enrichments in the polysulfide fraction are the result of a 

magnetic isotope effect, arising from the interaction of thiol-disulfide, ion-radical pairs formed 

during thermolysis at high temperatures. Furthermore, the absence of large 36 S enrichments, in 

combination with the fact that 33 S anomalies are only found in a fraction that represents several 

weight percent of the total sulfur in the system, argues strongly against the hypothesis that 

thermochemical sulfate reduction (TSR) can contribute substantially to Archean sulfur isotope 

anomalies. 

Figure 1 - S isotope plots of Δ 36 S vs. Δ 33 S (A) and δ 33 S vs. δ 34 S (B). Mass-dependent arrays (δ 33 S = 0.515 x δ 34 S) are plotted as 

grey lines. 

Page 37


ISI 2012: 18- 22 June 2012 



UTILIZING THE ISOTOPIC COMPOSITION OF NITRATE TO INVESTIGATE DEPOSITION TO 

SUMMIT, GREENLAND 

M.G. Hastings 1 , D.L. Fibiger 2 , J.E. Dibb 3 , C. Corr 3 , L.G. Huey 4 

1 Department of Geological Sciences and Environmental Change Initiative, Brown University, 

Meredith_Hastings@brown.edu, 2 Department of Chemistry, Brown University, 

Dorothy_Fibiger@brown.edu, 3 Earth System Research Center, Institute for the Study of the Earth, 

Ocean and Space, University of New Hampshire, jack.dibb@unh.edu, 4 School of Earth and 

Atmospheric Sciences, Georgia Institute of Technology, greg.huey@eas.gatech.edu. 

Atmospheric nitrate results from reactions of NOx (NO and NO 2 ) with oxidants in the atmosphere. 

The concentration and isotopic composition of nitrate in ice cores have been studied with the aims 

of reconstructing past NOx concentrations in the atmosphere, modeling past atmospheric oxidant 

concentrations and exploring variability in NOx sources. Post-depositional processing at the snow 

surface (e.g. photolytic loss or recycling), however, complicates our understanding and 

interpretation of nitrate found in snow and ice cores. 

In a campaign consisting of two springtime (May-June) field seasons at Summit, Greenland 

[72°35’N, 38°25’W], atmospheric and surface snow measurements were made to investigate the 

influence of locally processed/produced nitrate versus nitrate transported to Summit. Specifically, 

we look to use the nitrogen (δ 15 N-NO 3 - ) and oxygen isotopic composition of nitrate (Δ 17 O-NO 3 - , 

Δ 17 O-NO 3 - ) to track sources and chemistry of the nitrate that is deposited to Summit. The major 

oxidants in tropospheric nitrate formation have distinct isotopic compositions such that their 

relative contribution to NOx oxidation can be quantified based on Δ 17 O (Δ 17 O ≈ δ 17 O - 0.52×δ 18 O) 

of nitrate. Ozone’s mass independent fractionation signature (Δ 17 O = 25-35‰ vs. VSMOW in the 

troposphere) is transferred to nitrate via reaction with NOx to produce nitrate. The Δ 17 O of ozone 

is unique amongst the oxidants that convert NOx to atmospheric nitrate, with OH, HO 2 , and O 2 all 

expected to have Δ 17 O ≈ 0‰. 

In surface snow collected several times each day during the springtime field seasons, Δ 17 O-NO 3 

- 

ranges from 5-35‰ vs. VSMOW, δ 18 O-NO 3 

- 

from 35-85‰ vs. VSMOW, and δ 15 N-NO 3 - from -7 

to 13‰ vs. air N 2 . No relationship is found between the concentration of nitrate in snow and the 

isotopic composition of nitrate. A striking correlation between Δ 17 O- and δ 18 O-NO 3 

- 

is found 

throughout both field seasons, with a slope ~0.5 and r 2 > 0.9. This relationship appears to be a 

direct result of atmospheric production of nitrate, without significant post-depositional processing. 

Significant local processing (i.e. photolysis) of nitrate in the surface snow cannot explain this 

relationship between Δ 17 O and δ 18 O, except under very specific scenarios in which multiple 

processes consistently act in concert. A lack of loss of nitrate as NOx from the surface, however, 

disagrees with current models of local Summit photochemistry. Interestingly, comparison of the 

δ 15 N data with Δ 17 O and δ 18 O suggest a three-point mixing between three nitrate sources with the 

following isotopic compositions (δ 15 N, Δ 17 O, δ 18 O): (1) -8, 27, 74‰ (2) 6, 40, 100‰ and (3) 16, 0, 

23‰. 

Page 38


ISI 2012: 18- 22 June 2012 



ISOTOPIC FRACTIONATION IN OCS SINK REACTIONS AND IMPLICATION FOR THE SOURCE OF 

BACKGROUND STRATOSPHERIC SULFATE AEROSOLS 

Shohei Hattori 1 , Johan A. Schmidt 2 , Sebastian O. Danielache ,1 , Matthew S. Johnson 2 , Yuichiro 

Ueno 1 , Naohiro Yoshida 1. 1 Tokyo Institute of Technology, Japan , 

2 University of Copenhagen, Denmark. 

Carbonyl sulfide (OCS) is the most abundant sulfur containing gas in the atmosphere, with 

an average mole fraction of 500 ppt in the troposphere. Air currents carry OCS in to the 

stratosphere where it is decomposed by photolysis and radical reactions with OH and O( 3 P). The 

stratospheric sulfate aerosol (SSA) layer increases the Earth’s albedo and modulates the 

concentration of ozone because of surface heterogeneous reactions. Leung et al., (2002) reported 

an apparent fractionation constant for stratospheric OCS loss of 73.8±8‰ in 34 S for the lower 

stratosphere, based on OC 32 S and OC 34 S concentration profiles obtained by the JPL MkIV limb 

transmittance spectrometer. This extreme fractionation seemed to demonstrate that OCS is not a 

dominant source of SSA. 

In this study, we report the isotopic fractionation constant ( 34 ε) for the OCS sink reactions. 

For OCS photolysis, based on measurement of isotopologue-specific absorption cross sections, we 

find a small isotopic fractionation ( 34 ε = (1.1±4.2)‰) at 20 km altitude (Hattori et al., 2011). For 

the OCS sink reaction with O( 3 P) studied in a relative rate experiment at 298±2 K and 955±10 

mbar, a relatively small isotopic fractionation ( 34 ε = −21.7±6.2‰) was found (Hattori et al., 2012). 

Finally, for the OCS sink reaction with the OH radical, isotopic fractionation varies from −5 to 

0 ‰ depending on temperature and pressure (Schmidt et al., 2012), based on transition state theory. 

Overall these studies demonstrate that OCS sink reactions will not enrich but rather 

deplete product sulfate in 34 S, contradicting the result of Leung et al. (2002). In conclusion, based 

on the estimated value of δ 34 S(OCS) of 11‰ and the reported value of background SSA (δ 34 S = 

2.6‰), OCS is an acceptable source of background SSA. 

References 

Leung, F.-Y. T., Collusi, A. J., Hoffmann, M. R. Toon, G. C. Isotopic fractionation of carbonyl 

suldide in the atmosphere: Implication for the source of background of stratospheric 

sulfate aerosols. Geophys. Res. Lett., 29, 1474, 2002. 

Hattori, S., Danielache, S. O., Johnson, M. S., Schmidt, J. A., Kjaergaard, H. G., Toyoda, S., 

Ueno, Y., Yoshida, N. Ultraviolet absorption cross sections of carbonyl sulfide 

isotopologues OC 32 S, OC 33 S, OC 34 S and O 13 CS: isotopic fractionation in photolysis and 

atmospheric implications, Atmos. Chem. Phys., 11, 10293-10303, 2011. 

Schmidt, J. A., Johnson, M. S., Jung, Y., Danielache, S. O., Hattori, S., Yoshida, N., Predictions of 

the sulfur and carbon kinetic isotope effects in the OH + OCS reaction, Chem. Phys. Lett., 

531, 64-69, 2012. 

Hattori, S., Schmidt J. A., Mahler D., Danielache, S. O., Johnson M. S., Yoshida N. Isotope Effect 

in the Carbonyl Sulfide Reaction with O( 3 P), J. Phys. Chem. A, 116, 3521-3526, 2012. 

Page 39


ISI 2012: 18- 22 June 2012 



SO 2 PHOTOEXCITATION EXPLAINS MASS-INDEPENDENT FRACTIONATION IN PRESENT-DAY 

STRATOSPHERIC SULFATE 

Shohei Hattori 1 , Sebastian O. Danielache ,1 , Matthew S. Johnson 2 , Johan A. Schmidt 2 , Akinori 

Yamada 3 , Yuichiro Ueno 1 , Naohiro Yoshida 1 

1 Tokyo Institute of Technology, Japan , 2 University of Copenhagen, 

Denmark, 3 University of Tokyo, Japan. 

Mass-independent sulfur isotopic anomalies (non zero Δ 33 S and Δ 36 S) have been found in 

ice core sulfate associated with volcanic events. It has been suggest that this isotope anomaly is a 

reliable metric for events with a Volcanic Explosivity Index of 3 or above, with obvious utility in 

reconstructing the history of volcanic events able to impact climate. However a physicochemical 

model is necessary to extract information from the record and the details of the chemical 

mechanism have been lacking. Using UV absorption cross sections of 32 SO 2 , 33 SO 2 , 34 SO 2 and 

36 SO 2 from 250 to 320 nm (Danielache et al., 2008, 2012), calculated isotopic fractionation factors 

for SO 2 photoexcitation at altitudes of 10 to 60 km predict mass-independent distributions that are 

consistent with those found in stratospheric sulfate preserved in Antarctic snow and ice cores. 

Although the SO 2 + OH reaction is the dominant oxidation process in the plume, we find that MIF 

originating from SO 2 photoexcitation is transferred to sulfate due to the suppression of OH by 

ozone-depleting halogen reactions. While the slope δ 33 S / δ 34 S is sensitive to the initial 

concentrations of SO 2 , HCl and HBr,, Δ 36 S / Δ 33 S (-2 to -3) does not change, and both slopes are 

consistent with observations. For the first time we identify the process controlling the massindependent 

sulfur isotope anomaly in the present atmosphere and conclude that sulfur MIF in ice 

cores records the history of stratospheric volcanic eruptions. 

S. O. Danielache, C. Eskebjerg, M. S. Johnson, Y. Ueno and N. Yoshida, High precision 

spectroscopy of 32 S, 33 S and 34 S sulfur dioxide: Ultraviolet absorption cross sections and 

fractionation constants, Journal of Geophysical Research—Atmospheres, 113(D17), D17314, 

DOI: 10.1029/2007JD009695, 2008. 

S. O. Danielache, S. Hattori, M. S. Johnson, Y. Ueno, S. Nanbu and N. Yoshida, Photoabsorption 

cross-section measurements of 32 S, 33 S, 34 S and 36 S sulfur dioxide for the B 1 B 1 -X 1 A 1 

absorption band, J. Geophys. Res. Atmos. Submitted, 2012. 

Page 40


ISI 2012: 18- 22 June 2012 



PRESSURE BASELINE CORRECTION FOR ∆ 47 MEASUREMENTS 

Bo He 1 , Gerard Olack 1 , Albert Colman 1* . 1 The Department of the Geophysical Sciences, The 

University of Chicago, 5734 S. Ellis Ave., Chicago, IL 60615 USA, * corresponding author: 

asc25@uchicago.edu 

CO 2 “clumped isotope” measurements are becoming increasingly widespread in geochemical research, 

especially for paleothermometry and atmospheric chemistry studies (1,2) . This measurement on a 

magnetic sector isotope ratio monitoring mass spectrometer (IRMS) involves monitoring CO 2 + ion 

beams, including common ( 12 C 16 O 2 ) and singly substituted ( 13 C 16 O 2 , 12 C 16 O 18 O, 12 C 16 O 17 O) molecules. 

However, the key challenge is measuring the much smaller ion beam associated with multiply 

substituted isotopologues of CO 2 (e.g., 13 C 18 O 16 O, 12 C 18 O 2 ). Applications for CO 2 clumping center on 

the relative enrichment of mass 47, mainly 13 C 18 O 16 O, which is reported as ∆ 47 . However, the published 

analytical method (3) is primarily limited by: (1) the need to perform frequent heated gas calibrations 

because of secular drift (both short term and long term) in instrument performance; and (2) the large 

sample sizes (typically 5-10 mg of carbonate material) required to maintain relatively stable ion beam 

intensity (e.g., 16V for m/z 44) during acquisitions. A cold finger peripheral can be used to bypass the 

bellows of a dual inlet system by freezing over CO 2 into an isolatable fixed (small) volume in front of 

the capillary that delivers gas to the mass spectrometer’s ion source (4) . Sample sizes are selected to 

produce the targeted ion beam intensity, which declines markedly over the course of an acquisition as 

gas flows from cold finger to ion source, and tradeoffs exist between sample size, cold finger volume, 

and the conditions that favor beam intensity and stability. In both bellows mode and micro-volume 

mode, Δ 47 measurements are highly sensitive to the baseline signal on the m/z 47 collector. We have 

found that the baseline signal is likely a strong function of source gas pressure, and that it drifts through 

time, causing the shift in heated gas calibrations through time. 

We present two new approaches to determining ion beam intensity referenced to an interpolated 

“pressure baseline”. This involves new methods and data acquisition structures for more accurately 

determining the baseline signal on ion beams in sensitive (10 12 Ω resistor Faraday cups) collectors. We 

have established heated gas calibrations with the new acquisition structure under bellows and microvolume 

modes (our simulated cold finger runs for small sample sizes). Under both acquisition modes, 

the pressure baseline correction reduces the dependence of ∆ 47 values on conventionally defined δ 47 

values by up to an order of magnitude. Heated gas calibration (pressure baseline corrected) under 

micro-volume mode confirms the robustness of ∆ 47 measurements on small samples. Our achieved 

precision (1σ) under bellows mode is 6-8 ppm, and 10-12 ppm under micro-volume mode. Heated gas 

calibrations under both modes yield statistically indistinguishable results, and this approach practically 

eliminates the long-term drift in Δ 47 vs. δ 47 , leading to more precise and accurate Δ 47 measurements. 

There may be utility in applying these baseline corrections to measurements of other low abundance 

isotopologues. 

(1) Eiler JM (2007) Clumped-isotope geochemistry-The study of naturally-occurring multiplysubstituted 

isotopologues. EPSL, 262, 309. (2) Dennis KJ, Affek HP, Passey BH, Schrag DP and Eiler 

JM (2011) Defining an absolute reference frame for ‘clumped’ isotope studies of CO 2 . GCA, 75, 7117– 

7131. (3) Huntington KW, Eiler JM, Affek HP, Guo W, Bonifacie M, Yeung LY, Thiagarajan N, Passey 

B, Tripati A, Daeron M and Came R (2009) Methods and limitations of ‘clumped’ CO 2 isotope (Δ 47 ) 

analysis by gas-source isotope ratio mass spectrometry. J. Mass Spec. 44, 1318–1329. (4) Schmid TW 

and Bernasconi SM (2010) An automated method for ‘clumped-isotope’ measurements on small 

carbonate samples. Rapid Commu. Mass Spec. 24, 1955-1963. 

Page 41


ISI 2012: 18- 22 June 2012 



GLOBAL LONG-TERM MEAN TRIPLE OXYGEN ISOTOPE COMPOSITION OF TROPOSPHERIC 

CO 2 

Magdalena E.G. Hofmann * , Balázs Horváth, Andreas Pack. Georg-August Universität, 

Geowissenschaftliches Zentrum, Abteilung Isotopengeologie, Goldschmidtstraße 1, 37077 

Göttingen, Germany ( * magdalena.hofmann@geo.uni-goettingen.de) 

Introduction: The oxygen and carbon isotope composition ( 18 O/ 16 O and 13 C/ 12 C) of tropospheric 

CO 2 is an excellent tool to investigate the atmospheric CO 2 cycle. Hoag et al. [1] suggested that 

the triple oxygen isotope composition ( 17 O/ 16 O and 18 O/ 16 O) of tropospheric CO 2 is a potential new 

tracer for terrestrial gross primary production (GPP). Here, we investigate in detail the global longterm 

mean triple oxygen isotope composition of tropospheric CO 2 and discuss its sensitivity to the 

major CO 2 fluxes, in particular GPP and stratospheric CO 2 influx. 

Method: We conduct mass balance calculations for both δ 18 O and Δ 17 O TFL of tropospheric CO 2 in 

order to reconcile the assumptions for 18 O/ 16 O and 17 O/ 16 O fractionation of atmospheric CO 2 . In 

doing so, we carefully assign triple oxygen isotope signatures to the main CO 2 sources and sinks. 

For CO 2 -water exchange, we implement the triple oxygen isotope exponent θ CO2-water = 

0.522±0.002 [2] and we take into account that the main water reservoirs that exchange with 

atmospheric CO 2 (ocean, soil and leaf water) have a distinct Δ 17 O TFL signature [3, 4]. For 

kinetically fractionated CO 2 sources and sinks we assume that the exponent λ kinetic = 0.509 [5]. We 

test the sensitivity to the main carbon fluxes and fractionation processes. We also compare the 

mass balance calculations to the long-term mean triple oxygen isotope composition of ambient air 

sampled in Göttingen (NW Germany) and with samples from remote locations [6]. All triple 

oxygen isotope data are reported relative to the terrestrial fractionation line (TFL) with a slope 

λ TFL =0.5251 and zero intercept. 

Results: For our base scenario, we calculate a global triple oxygen isotope composition of 

tropospheric CO 2 with δ 18 O VSMOW = 41.3‰ and Δ 17 O TFL = -0.12‰. Ambient air CO 2 from 

Göttingen has a long-term mean triple oxygen isotope composition with δ 18 O VSMOW = 41.5±0.9‰ 

(SD) and Δ 17 O TFL = -0.12±0.06‰ (SD). 

Discussion: Several studies on δ 18 O of atmospheric CO 2 demonstrated that assimilation and 

respiration are the two opponents controlling the global mean δ 18 O of tropospheric CO 2 [7-10]. 

Here, we show that assimilation is the main driver that tends to decrease the Δ 17 O TFL of 

tropospheric CO 2 whereas both soil respiration and stratospheric influx are the main drivers that 

tend to increase the Δ 17 O TFL value. The model output for our base scenario is in excellent 

agreement with the long-term mean triple oxygen isotope composition of ambient air from 

Göttingen. The sensitivity tests show that Δ 17 O TFL of tropospheric CO 2 is sensitive to changes in 

GPP and stratospheric CO 2 influx, and thus, has a great potential to complement δ 18 O modeling of 

atmospheric CO 2 . 

[1] Hoag, K.J., et al., Geophys. Res. Lett., 2005. 32(L02802): p. 1-5. [2] Hofmann, M.E.G., B. Horváth, and 

A. Pack, Earth Planet. Sci. Lett., 2012. 319-320: p. 159-164. [3] Landais, A., et al., Geochim. Cosmochim. 

Acta, 2006. 70(16): p. 4105-4115. [4] Luz, B. and E. Barkan, Geochim. Cosmochim. Acta, 2010. 74(22): p. 

6276-6286. [5] Young, E.D., A. Galy, and H. Nagahara, Geochim. Cosmochim. Acta, 2002. 66(6): p. 1095- 

1104. [6] Horváth, B., M.E.G. Hofmann, and A. Pack. in ISI. 2012. [7] Ciais, P., et al., J. Geophys. Res., 

1997. 102(D5): p. 5857-5872. [8] Peylin, P., et al., Physics and Chemistry of The Earth, 1996. 21(5-6): p. 

463-469. [9] Cuntz, M., et al., J. Geophys. Res., 2003. 108(D17): p. ACH1-ACH23. [10] Cuntz, M., J. 

Geophys. Res., 2003. 108(D17): p. ACH2.1-ACH2.19. 

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TRIPLE OXYGEN ISOTOPE EXPONENT FOR PHOSPHORIC ACID DECOMPOSITION OF 

CARBONATES 

Magdalena E.G. Hofmann * , Balázs Horváth, Andreas Pack. Georg-August Universität, 

Geowissenschaftliches Zentrum, Abteilung Isotopengeologie, Goldschmidtstraße 1, 37077 

Göttingen, Germany ( * magdalena.hofmann@geo.uni-goettingen.de) 

Introduction: The triple oxygen isotope composition of terrestrial carbonates might provide yet 

overlooked information on the formation process of biogenic and abiotic carbonates. We expect slight 

variations due to different triple oxygen isotope compositions of the water from which the carbonate 

precipitated. First, we determined the exponent λ acid-fractionation for phosphoric acid decomposition, which 

is a prerequisite for inferring the triple oxygen isotope composition of the carbonate from the released 

CO 2 . Second, we analyzed different carbonate samples to detect possible Δ 17 O variations. 

Method: Phosphoric acid decomposition of carbonates was carried out at 25°C. Subsequently, the 

liberated CO 2 was analyzed by a CO 2 -CeO 2 equilibration method [3]. All triple oxygen isotope data are 

reported relative to the terrestrial fractionation line (TFL) with a slope λ TFL = 0.5251±0.0007 and zero 

intercept (Δ 17 O NBS-28 = 0‰). We investigated a variety of terrestrial carbonates from different 

formation processes (a metamorphic calc-silicate rock, a stalagmite, a modern sclerosponge, cap 

carbonates and Solnhofen limestone). We inferred the exponent λ acid-fractionation from the calc-silicate 

rock analyzing the Δ 17 O TFL of the CO 2 released from the carbonate and the Δ 17 O TFL of the 

accompanying mineral phases (forsterite, spinel and clinohumite). 

Results: The δ 18 O VSMOW value of the carbonates varied between 15 and 30‰. The mean Δ 17 O TFL value 

of CO 2 released from theses carbonates was -0.15±0.05‰ (SD, n=59). No significant difference in 

Δ 17 O TFL between the carbonate samples was observed. The δ 18 O VSMOW value of the calc-silicate 

carbonate was 19.6‰. The Δ 17 O TFL value of the CO 2 released from the calc-silicate carbonate 

was -0.15±0.01‰ (SE, 1σ). The mean δ 18 O VSMOW value of forsterite, spinel and clinohumite was 

17.8±0.2 (SD) and the Δ 17 O TFL value was 0.0±0.02‰ (SE, 1σ). The small difference in δ 18 O (


ISI 2012: 18- 22 June 2012 



TRIPLE OXYGEN ISOTOPE COMPOSITION OF TROPOSPHERIC CARBON DIOXIDE AND ITS 

SEASONAL VARIATION 

Horváth * B., Hofmann M.E.G., Pack A. Georg-August-Universität, Geowissenschaftliches 

Zentrum, Abteilung Isotopengeologie, Goldschmidstraße 1, 37077 Göttingen, Germany 

* bhorvat@gwdg.de 

The 13 C/ 12 C and 18 O/ 16 O ratios of CO 2 are traditionally used for investigations on the carbon cycle. 

The 17 O/ 16 O ratio was neglected for a long time, as it was expected to be coupled to the variations 

of the 18 O/ 16 O ratio. However, there are two sources for “anomalous” CO 2 in the troposphere: 

stratospheric CO 2 has a positive oxygen isotope anomaly [1], fossil fuel combustion CO 2 carries a 

negative isotope anomaly [2]. (The anomaly is expressed here as Δ 17 O = δ’ 17 O − 0.5251 × δ’ 18 O, 

where 0.5251 is the slope (λ) of the terrestrial fractionation line; it was assumed that Δ 17 O of 

NBS28 = 0.00‰). Thus, Δ 17 O of CO 2 is a promising tool both for global carbon modeling and for 

urban air studies. 

We present high-precision Δ 17 O values of atmospheric CO 2 . The triple oxygen isotope 

composition of CO 2 was determined following the protocol published in [3, 4]. Accuracy and 

precision of Δ 17 O (single analysis) was better than ± 0.05 ‰ (1σ, SD). 

The CO 2 samples were collected on the campus of the University of Göttingen (NW Germany), 

between June 2010 and March 2012. The average Δ 17 O value of CO 2 was −0.12±0.06‰ (1σ, SD), 

which is in accordance with the prediction of a global mass balance model for tropospheric CO 2 

[5]. The Δ 17 O values of ambient CO 2 show a seasonal variation: highest values (−0.07‰) were 

measured in May, lowest in November (−0.17‰). A similar pattern was found for the δ 18 O value 

of CO 2 with a mean of 41.5‰ and an amplitude of 0.9‰. The accordance of the curves suggests 

that the Δ 17 O seasonal variation is driven by the same biological processes than the δ 18 O seasonal 

cycle. 

The regional mass balance model suggests that biological processes have a decisive effect on the 

seasonal variation of Δ 17 O of CO 2 ; carbon dioxide from local anthropogenic sources may decrease 

the Δ 17 O value by 0.02‰ in winter. However, the model predicts a temporal pattern with lowest 

values in June, which is in contrast to the measured values. 

Seasonal variation in the influx of anomalous stratospheric CO 2 could be an explanation for this 

contradiction. However, this is not supported by other stratospheric tracers, like 14 C [6]. The other 

possibility is that the triple oxygen isotope signature of CO 2 from biological sources is different 

than assumed. Ongoing measurements on soil respired and leaf water equilibrated CO 2 should 

clarify remaining uncertainties. 

[1] Thiemens, M., T. Jackson, and C.A.M. Brenninkmeijer, Geophys. Res. Lett., 1995. 22(3): p. 

255-257. [2] Horváth, B., M.E.G. Hofmann, and A. Pack. in Tenth Informal Conference on 

Atmospheric and Molecular Science. 2011. [3] Hofmann, M. and A. Pack, Anal. Chem., 2010. 

82(11): p. 4357-4361. [4] Hofmann, M.E.G., B. Horvath, and A. Pack, Earth. Planet. Sci. Lett., 

2012. 319(0): p. 159-164. [5] Hofmann, M.E.G., B. Horváth, and A. Pack, Global long-term mean 

triple oxygen isotope composition of tropospheric CO 2 This conference. [6] Levin, I., et al., Sci. 

Total Environ., 2008. 391(2): p. 211-216. 

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LONGTERM SIMULATION OF TROPOSPHERIC AND STRATOSPHERIC N 2 O ISOTOPOMERS AND 

ITS APPLICATION TO GLOBAL BUDGET ESTIMATIONS 

Kentaro Ishijima 1 , Sakae Toyoda 2 , Masayuki Takigawa 1 , Kengo Sudo 3 , Takakiyo Nakazawa 1, 4 , 

Shuji Aoki 4 , Thomas Röckmann 5 , Jan Kaiser 6 , Chisato Yoshikawa 2 , Shinkoh Nanbu 7 , Naohiro 

Yoshida 2 . 1 Research Institute for Global Change, JAMSTEC, Japan < ishijima@jamstec.go.jp> 2 

Interdisciplinary Graduate School of Science and Engineering, Tokyo institute of Technology, 

Japan. 3 Graduate School of Environmental Studies, Nagoya University, Japan. 4 Center for 

Atmospheric and Oceanic Studies, Tohoku University, Japan. 5 IMAU, Faculty of Physics and 

Astronomy, Utrecht University, Netherlands. 6 School of Environmental Sciences, University of 

East Anglia, UK. 7 Department of Materials and Life Sciences, Faculty of Science and Technology, 

Sophia University, Tokyo, Japan 

We have performed long-term simulations of tropospheric and stratospheric N 2 O isotopomers with 

realistic surface emissions and meteorological fields using a chemistry-coupled atmospheric 

general circulation model (ACTM). Some sensitivity runs have been also done for photolysis in 

the stratosphere and meteorology, since the model sometimes underestimated kinetic isotopomer 

fractionations compared with balloon observations (Toyoda et al., 2004; Kaiser et al., 2006). 

Under the model simulation framework, global mean emissions of isotopomers ( 14 N 14 N 16 O, 

14 N 15 N 16 O, 15 N 14 N 16 O and 14 N 14 N 18 O) for the period 1990-2002 are estimated by fitting the model 

results to high-precision N 2 O isotopomer measurements at the surface (Röckmann and Levin, 

2005), with a newly-devised multi-emission simulation method. This approach has been applied 

also to the preindustrial N 2 O isotopomers in 1750 using ice core analyses data (Bernard et al., 

2006), and we first estimate their emissions. Isotopomer ratios of both the present and the 

preindustrial global N 2 O emissions are within the range of soil sources, although they show 

somewhat significant dependency on photochemical fractionations in the stratosphere. However, 

isotopomer ratios of the global total anthropogenic sources, derived from difference between the 

present and preindustrial emissions, converge on small ranges, which are similar to those by 

previous observational studies, regardless of photochemistry sensitivity cases. 

Bernard, S., T. Röckmann, J. Kaiser, J.-M. Barnola, H. Fischer, T. Blunier, and J. Chappelaz 

(2006), Constraints on N 2 O budget changes since pre-industrial time from new firn air and 

ice core isotoper measurements, Atmos. Chem. Phys., 6, 493-503. 

Kaiser J., A. Engel, R. Borchers, and T. Röckmann, Probing stratospheric transport and chemistry 

with new balloon and aircraft observations of the meridional and vertical N 2 O isotope 

distribution (2006), Atmos. Chem. Phys., 6, 3535–3556. 

Röckmann, T., and I. Levin (2005), High-precision determination of the changing isotopic 

composition of atmospheric N 2 O from 1990 to 2002, J. Geophys. Res., 110, D21304, 

doi:doi:10.1029/2005JD006066. 

Toyoda, S., N. Yoshida, T. Urabe, Y. Nakayama, T. Suzuki, K. Tsuji, K. Shibuya, S. Aoki, T. 

Nakazawa, S. Ishidoya, K. Ishijima, S. Sugawara, T. Machida, G. Hashida, S. Morimoto, 

and H. Hondaet al. (2004), Temporal and latitudinal distributions of stratospheric N 2 O 

isotopomers, J. Geophys. Res., 109, D08308, doi:10.1029/2003JD004316. 

Page 45


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CO-ORGANIZATION OF FUNCTIONS OF ISOTOPY AND GRAVITATION IN EMBRYOGENESIS 

COHERENCE 

A.A. Ivanov, Vernadsky Institute of Geochemistry and Analytical Chemistry, Moscow, Russia, 

aiva@geokhi.ru 

Studies of the nature of determination of genetic expression during embryogenesis 

revealed a tight relationship between isotopy and blastomer DNA methylation [1]. At early stages 

of embryogenesis during zygote fractionation, DNA amplification with use of free nucleotides 

pool takes place. Different isotopic forms from the free nucleotides pool unequally participate in 

this process. For example, due to kinetic isotopic effect, light isotope forms are more quickly 

involved in the process of DNA replication. The process is determined because the zygote is a 

closed system for nucleotides and they are not synthesized de novo and the isotopic light forms are 

more actively used in the kinetics of this process. In the result, the residual pool of nucleotides 

becomes more isotopically heavy. So, each stage has an individual and original isotopic 

composition of the residual pool of nucleotides and this is inherited by polynucleotide strands of 

each DNA pairs synthesized at their own stage. A wide set of DNA polynucleotide pairs will arise 

in the final stage of the zygote fractionation. One strand will be synthesized in the final stage and, 

hence, will be the most isotopic heavy, because the pool of light nucleotides is exhausted at the 

moment. But another, forming a pair, strand will possess its own individual isotopy, reflecting the 

isotopic composition of the stage of its synthesis. Thus, various isotopic effects that accompany 

the zygote fractionation lead to regulation of DNA isotopy. Isotopy of all polynucleotide pairs of 

DNA in the final stage of the zygote fractionation will have individual pattern of regulating. We 

have revealed in experiments that various isotopic forms of DNA are methylated differently. 

Regulation of DNA isotopy leads to putting into order methylation of nucleotides, forming 

characteristic pattern of methylation that is responsible for genetic expression and provides 

functioning of differentially specialized cells in each multicellular organism. 

Under conditions of the weightlessness in reduction of the kinetic isotopic effect, the 

zygote fractionation will not be accompanied by regulated distribution of isotopically different 

forms of nucleotides in blastomer DNA that will impair the process of self-organization of the 

methylation pattern determining genetic expression of DNA of all embryonic cells. As a 

consequence, the absence of gravitation at the stage of zygote fractionation will be critical. So, if 

there is no gravitation, then there is no following consecutive events: no differential isotopy of 

blastomer DNA – no characteristic pattern of DNA methylation – no functional specialization of 

cells – no regularity of ontogenesis! 

1. A.A. Ivanov. Isotopic Self-Programming for the Embryonic Cell DNA Methylation Pattern. 

<strong>International</strong> Research Journal of Pure&Applied Chemistry. 2011, 1(2), 58. 

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CLUMPED ISOTOPES APPLIED TO RESEARCH ON DIAGENESIS TOWARDS RESERVOIR 

CHARACTERIZATION 

Anne-Lise Jourdan 1,* , Cédric M. John 1 , Simon Davis 1 

1 Imperial College London, Department of Earth Science and Engineering, London SW7 2AZ, 

United Kingdom. * a.jourdan@imperial.ac.uk 

The “clumped isotope carbonate paleothermomether” can determine within a few degrees the 

temperature of formation of a carbonate mineral without having to know the composition of the 

fluid from which it precipitates. 

This is therefore a very valuable tool for diagenetic studies, particularly in the context of 

subsurface reservoirs characterisation. Indeed, modifications of reservoirs properties by diagenetic 

processes are widespread and important, as carbonate minerals are very reactive minerals. 

Therefore, post-depositional diagenetic processes such as dissolution and re-precipitation of new 

minerals can easily modify the porosity and permeability of the initial carbonate rock during burial 

and exhumation. 

Knowing the temperature at which diagentic modifications occurred, and henceforth possibly the 

depth at which they took place, represents an useful insight into understanding and reconstructing 

the diagenetic history of a reservoir. 

We present here the clumped isotope results obtained on outcrop carbonate samples from Oman, 

representing possible reservoir analogues. Preliminary data allows us to determine the temperature 

of formation (i.e around 65°C) of calcite crystals sampled in fracture infills in Jebel Madar, a 

fractured carbonate carapace above a salt-dome. It also helps us determine the composition of the 

fluid from which the calcite crystals formed (d 18 O= -5.6‰). Associated with a wider study of the 

diagenitic environment, we could assess that the meteoric water has a high salinity due to contact 

with the salt dome. We could now understand better the mechanisms linked to the post 

depositional transformation of this particular outcrop. 

Furthermore, we are currently calibrating clumped isotopes thermometry to high-temperature 

diagenetic cements. The current published clumped isotopes calibrations are limited to 

temperatures from 0-80°C, whereas to fully reflect reservoir conditions we are aiming to extend 

the calibration up to 300˚C for a range of mineralogical composition and a range of fluid 

composition, reflecting composition determined by fluid inclusion characterisation on outcop 

samples. 

The project is part of the Qatar Carbonate and Carbon Storage Research Centre (QCCSRC), 

funded jointly by Qatar Petroleum, Shell and the Qatar Science and Technology Park. 

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TOWARDS AN 17 O CHRONICLE OF THE ~635 MA GLOBAL GLACIAL MELTDOWN 

Bryan Killingsworth 1,* , Justin Hayles 1 , Chuanming Zhou 2 , and Huiming Bao 1 

1 Department of Geology and Geophysics, Louisiana State University, Baton Rouge, Louisiana 

70803, USA, * bkilli1@lsu.edu. 2 State Key Laboratory of Palaeobiology and Stratigraphy, Nanjing 

Institute of Geology and Paleontology, Chinese Academy of Sciences, Nanjing 210008, China 

The enigmatic occurrence of barite crystal fans just above the Marinoan glaciation “cap carbonates”, 

~635 Ma, preserved a record of conditions in the atmosphere, hydrosphere, and biosphere in the 

aftermath of a possible “Snowball Earth”. Non-mass-dependent depletion of 17 O in sulfate is a unique 

geochemical signature which has been interpreted to indicate an ultra-high pCO 2 atmospheric condition. 

However, critical information of the Marinoan 17 O-depletion (MOSD) event is its duration, which is 

unfortunately unconstrained at this time, due to incomplete occurrence of minerals or host rocks that 

bear the 17 O-anomalous sulfate. One way to remediate the situation is to identify a section where the 

sulfate 17 O record is the most complete and use the section as the archetype with which to 

stratigraphically correlate the MOSD records in different depositional environments regionally and 

perhaps globally. Here we build on previous work (Bao et al., 2008; Zhou et al., 2010; Peng et al., 

EPSL 305, 21-31, 2011) and report a new section in Wushanhu, Hubei, where at least 11 distinct barite 

layers occur within 1 meter thickness of basal Doushantuo dolostone deposited in an inner shelf 

environment. Preliminary data (see figure) show that at least 5 of the 11 barite layers bear distinct 17 O- 

depletion (i.e. ∆ 17 O < -0.25‰). In general, the lower 7 barites have more 17 O-anomalies, contrasting 

with the normal 17 O of the upper layers. Barite sulfur compositions show lower and more variable δ 34 S 

becoming increasingly more 34 S-enriched up-section (up to 44‰). In addition, correlations between 

geochemical parameters and sedimentary features are identified. Ultimately, this barite-based 17 O 

chronicle will provide a foundation for interbasinal comparison of the duration of the MOSD event and 

reveal the dynamics of a dramatic biosphere and atmosphere response at the end of one of the most 

extreme global glaciations in Earth history. 

Basal dolostone sequence of the 

Doushantuo Formation at Wushanhu, 

Hubei, China with measured isotope 

composition, δ 34 S and Δ 17 O, of barite. 

Stratigraphic height is given in cm above 

the top of the Nantuo Formation glacial 

diamictite. 

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OXYGEN ISOTOPES (δ 18 O VS δ 17 O) CHARACTERIZE MICROBIAL PYRITE OXIDATION 

PRODUCTS: A NEW BIOMARKER? 

Issaku Kohl, Justin Christensen, Randy Mielke, Karen Ziegler, Bryan Killingsworth, Ed Young, 

and Max Coleman Jet Propulsion Laboratory, M/S 306-326, 4800 Oak 

Grove Drive, Pasadena, CA, 91109. 

Identifying definitive biomarkers for Mars is still a high priority. Sulfate minerals 

preserve the oxygen isotopic signal imparted during their formation. The apparent 

abundance of sulfate minerals on the Martian surface and the involvement of microbes in 

the catalysis of reduced sulfur oxidation here on Earth, makes sulfate-oxygen an ideal 

candidate biomarker. The Río Tinto (Red River) in southern Spain is a typical Acid Mine 

Drainage site, where massive pyrite (iron sulfide) deposits are continuously being 

oxidized. Bacteria catalyze the oxidation of sulfur and Fe(II) with atmospheric oxygen to 

form sulfate and Fe(III). However, Fe(III) indirectly oxidizes sulfur at pH< 3 abiotically 

using oxygen from water. The past Martian environment could have been quite similar to 

the acidic, sulfate and Fe(III) rich Río Tinto waters. 

Despite Río Tinto sulfate-oxygen being a good candidate for biomarker 

preservation, traditional isotopic measurements have not been able to differentiate biotic 

from abiotic oxidation products. Here we introduce a new parameter to distinguish 

microbially catalyzed pyrite oxidation from sulfate produced or modified by other 

pathways. We made high precision triple-oxygen isotope measurements to determine 

process specific δ 18 O vs. δ 17 O slopes for sulfates produced via: 1) microbial pyrite 

oxidation by Acidothiobacilus ferrooxidans (0.5127); 2) natural, Rio Tinto microbial 

pyrite oxidation (0.5177); 3) sulfate reduction with added complexity and mixing (0.528). 

The slope measured for Rio Tinto sulfate (three seasons’ field sampling) implies a 30% 

slope contribution from sulfate reduction and suggests that we have a new biomarker. 

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INSIGHTS ON THE DEEP SULFUR CYCLE USING MULTIPLE S ISOTOPES IN MID-OCEAN RIDGE 

BASALTS 

J. Labidi 1 , P. Cartigny 1 . 1 Stable Isotope Laboratory, IPGP, France. labidi@ipgp.fr 

In order to provide constraints on the origin, distribution and cycling of Sulfur among the 

different terrestrial reservoirs, we studied multiple Sulfur isotope on 159 Mid Ocean Ridge Basalts 

(MORB) from the Indian, Atlantic and Pacific ridges. These lava samples are erupted on the 

seafloor, at sufficiently high water pressure to exclude degassing. The MORB S isotope 

composition is thus the closest estimate of their mantle source regions. Using an improved method 

allowing quantitative recovery of sulfur from basaltic glasses, we report data with external 

precision to be ± 0.005‰, 0.10‰ and 0.10‰ in 1s for Δ 33 S, δ 34 S, and Δ 36 S respectively. 

All our samples are homogeneous in both 33 S and 36 S isotope composition, yet slightly 

depleted compared to the theoretical mass-dependent prediction, with a mean Δ 33 S of -0.018 ± 

0.006 (1s) and a mean Δ 36 S of -0.178 ± 0.074 (1s). Besides, almost all the basalts are 34 S depleted 

when compared to the Canyon Diablo Troilite (CDT) standard. Their mean δ 34 S is -0.77 ± 0.44 ‰ 

(1s), varying between -1.83 and +1.05‰. 

The trace element enriched MORB (or E-MORB) display a larger δ 34 S variability than the 

depleted MORB (or N-MORB), exhibiting the highest δ 34 S (> 0 ‰). This suggests that the 

recycled components likely occurring in the source of the E-MORB carry sulfur of distinct isotope 

composition than the ambient mantle. 

In contrast, the Δ 33 S and Δ 36 S are strikingly homogeneous, uncorrelated to δ 34 S or any 

mantle tracer. We use these values as representative of the whole upper mantle to address the 

steady-state of S cycle. The δ 34 S have been reported to be 0.0 ± 0.5 (1s) in chondrites [1-2], 

statistically distinct from our upper mantle estimate. In contrast, the chondritic δ 33 S and δ 36 S are 

not known with a comparable level of precision. Assuming that the primitive mantle has a 

chondritic composition of δ 34 S = δ 33 S = δ 36 S = 0.000‰, the upper mantle values suggest that the 

geological processes that have occurred over the last 4.5 Ga shifted the Earth mantle from its 

primordial values. 

Mixing between subducted components could conceptually accounts for the present day 

mantle values. Alternatively, the Δ 33-36 S could be remnants of the primitive mantle signature, 

undisturbed by the continental extraction likely occurring since at least 3 Ga. In this case, our 

estimate of the upper mantle δ 33-36 S would represent the bulk silicate Earth (BSE), defining the 

best accurate reference frame in multiple S isotopes for the Earth. In this view, the low δ 34 S of the 

depleted mantle reveals a possible role for core-mantle segregation or catastrophic degassing to 

control the mass-dependent S isotope compositions of the mantle 

[1] Gao and Thiemens (1993) Geochimica et Cosmochimica Acta, vol. 57, p 3171-3176. [2] Gao 

and Thiemens (1993) Geochimica et Cosmochimica Acta, vol. 57, p 3159-3169 

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ISOTOPE FRACTIONATION FACTORS CONTROLLING ISOTOPOLOGUE SIGNATURES OF 

SOIL-EMITTED N 2 O PRODUCED BY DENITRIFICATION PROCESSES OF VARIOUS RATES. 

Dominika Lewicka-Szczebak 1 , Reinhard Well 2 , Laura Cardenas 3 , Peter Matthews 4 , Tom 

Misselbrook 3 , Roland Bol 3, 5 , Richard Whalley 3 , Andy Gregory 3 

1 Thünen-Institut, Germany/Uniwersytet Wroclawski, Poland; dominika.lewickaszczebak@vti.bund.de, 

2 Thünen-Institut, Germany; 3 Rothamsted Research,UK, 4 University of 

Plymouth, UK; 5 Forschungzentrum Juelich, Germany 

Isotope fractionation factors related to denitrification are still poorly examined due to 

complexity of this process. The isotopologue signatures of N 2 O produced in course of 

denitrification are governed by the isotope fractionation occurring during its production (NO 3 - – 

N 2 O reaction step) and its reduction (N 2 O – N 2 reaction step). Hence, for a reliable modelling of 

fractionation factors of both N 2 O production and reduction, the independent data on the quantity of 

N 2 O reduction are necessary. Our modelling presented here is based on the laboratory incubation 

carried out under the N 2 -free atmosphere, where the fluxes of both N 2 O and N 2 , after application of 

C and N to soil cores, were analyzed continuously (in ca. 2 hours intervals) and the samples for 

N 2 O isotopologue analysis were collected once a day. The incubated soil cores were subjected to 

four different water saturation conditions under controlled temperature. 

The modelling approach was applied to decipher the mechanisms of N 2 O production under 

anaerobic conditions. The measured fluxes were used to determine the fraction of consumed NO 3 

- 

and the fraction of reduced N 2 O. The Rayleigh equations and literature data on isotope 

fractionation factors were used to calculate the theoretical δ 15 N N2O values for each vessel. 

Comparison of modelled and measured values indicated that a 2-pool model assumption is the 

most appropriate here, where pool 1 is the soil volume with the amendment, and pool 2 is the 

remaining soil not reached by the amendment diffusion. Pool 1 is characterized by very rapid N 2 O 

production rates and moderate N 2 O reduction rates, whereas pool 2 is characterized by much lower 

N 2 O production rates and intensive N 2 O reduction. Very different reaction rate constants for both 

pools must be also related with different fractionation factors. Therefore, in the next step of the 

modelling, individual fractionation factors were assumed for both pools to reach the best fit of 

modelled and measured values. 

It was found that the fractionation factors differ depending on the process intensity, i.e. the 

magnitude of isotopic fractionation increases with decreasing reaction rate. This pattern is 

especially clear for the wet treatments, where micropores were saturated and the fluxes were the 

largest. The value of ε 15N(NO3-N2O) for slow rates production in pool 2 ranged from -32 to -23% 

(with the mean value of -27‰), whereas for fast rate production in pool 1 it was lower and varied 

from -42 to -25‰ (with the mean value of -32‰). The isotopic fractionation factors for N 2 O 

reduction show similar pattern. The ε SP(N2O-N2) value varied from about -4% for slow rate reduction 

to about -1% for fast rate reduction. And similarly, the ε 18O(N2O-N2) value varied from about -13% 

for slow rate reduction to about -5% for fast rate reduction. 

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THEORETICAL CALCULATIONS OF EQUILIBRIUM CLUMPED ISOTOPE SIGNATURES BEYOND 

HARMONIC APPROXIMATIONS 

Qi Liu, Xinya Yin, Yun Liu * . Institute of Geochemistry, Chinese Academy of Sciences, Guiyang, 

China. liuyun@vip.gyig.ac.cn 

Clumped isotope geochemistry studies isotopic distributions of isotopologues containing more than one 

rare isotope and can provide unique information such as the formation temperatures of geologic 

samples. The measurement of clumped isotope signatures in laboratory needs calibrations using 

observed isotopic data and formation temperatures in order to take account those isotopic fractionations 

occurred in experimental procedures. One of the calibration methods is to measure the clumped isotope 

signatures of temperature-known materials and scale the temperature curve to match experimental data. 

Theoretical calculation using quantum chemistry methods could also be an alternative. However, the 

precision required for clumped isotope calculation is very high. Theoretical treatments beyond 

harmonic approximations are therefore highly recommended. 

In this study, theoretical treatments beyond the harmonic level by including several higher-order 

corrections to the Bigeleisen-Mayer equation are used to predict accurate Δ i and Δ mass results for 13 C- 2 H 

and 2 H-C- 2 H clumps in many organic compounds. The details of these higher-order corrections can be 

found in our previous work ([1]). 

The following table is an example to show what our calculation results will look like. The calculated 

RPFR (or beta value) results of methane (CH 4 ) are shown at below at 298.15K, using B3LYP/6- 

31+G(d,p) level and without corrections for Fermi and Darling-Dennison Resonances. AnZPE, AnEXC, 

VrZPE, VrEXC, QmCorr and CenDist are six higher-order corrections used in this case. For other 

organic molecules with hindered internal rotation, we will also apply relevant corrections for it. CPFR 

is the corrected final RPFR results. No scale factor is used for frequencies and anharmonic constants. 

B3LYP/6-31+G(d,p) AnZPE AnEXC VrZPE VrEXC QmCorr CenDist Total RPFR CPFR 

13 CH 4 /CH 4 0.9952 1.0000 0.9999 1.0000 1.0000 1.0000 0.9951 1.1193 1.1139 

CDH 3 /CH 4 0.9039 1.0003 0.9979 1.0000 0.9988 1.0001 0.9013 11.5428 10.4040 

13 CDH 3 /CH 4 0.8995 1.0004 0.9979 1.0000 0.9988 1.0001 0.8969 12.9950 11.6556 

CD 2 H 2 /CH 4 0.8423 1.0009 0.9963 1.0001 0.9980 1.0001 0.8383 135.8391 113.8801 

If using the above corrected RPFR results, we can estimate the anharmonic corrections on 

harmonic Δ i values. For the calculated Δ 13CDH3 value (it will be 5.82‰), the anharmonic correction we 

find here is quite small (about 1 to 2 percent), it is probably smaller than what Cao and Liu (2012) 

predicted ([2]) (i.e., about 5 percent). For the calculated Δ CD2H2 value (it will be 50.77‰), the 

anharmonic correction is very large (about 160 percent). 

Our results of different theoretical methods all suggest significant improvements on the calculations of 

13 C- 2 H and 2 H-C- 2 H clumped isotope fractionations. If Fermi resonances and Darling-Dennison 

resonances are ignored (because there is no precise and reliable computational method to treat them 

now), there would be small or negligible anharmonic correction for the Δ i values of 13 C- 2 H clumped 

isotopes. However, extremely large anharmonic correction is still needed for the calculation of 2 H-C- 2 H 

clumping. 

[1] Liu et al. (2010) Geochim. Cosmochim. Acta 74, 6965-6983. [2] Cao and Liu (2012) Geochim. Cosmochim. Acta 77, 

292-303. 

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A CLUSTER-MODEL-BASED CALCULATION METHOD FOR ISOTOPIC FRACTIONATIONS OF 

SOLIDS 

Yun Liu, * Mao Tang. Institute of Geochemistry, Chinese Academy of Sciences, Guiyang, China. 

 

There is a tremendous interest in developing a cluster-model-based calculation method of 

isotopic fractionations for solids because most of the new techniques developed in modern 

quantum chemistry are for molecules which usually are represented by cluster models. Many local 

properties of solids (e.g., isotopic effect) can be calculated using much higher theoretical 

treatments if using cluster models. Another reason we developed this method is to remedy 

problems raised from a similar method used by Rustad and co-workers (e.g.,[1]), especially to 

enhance its implementation on isotope fractionation calculations between solids and aqueous 

species. For the test of this new cluster-model-based method, equilibrium C, Ca, Mg and O isotope 

fractionations of minerals are evaluated. Clumped isotope distributions of several carbonate 

minerals are also investigated. 

Recent studies (e.g., [2],[3],[4]) suggested the possibility of using equilibrium inter-mineral Mg 

isotope fractionations as a thermometer at mantle conditions. Here, we calculate equilibrium Mg 

and O isotope fractionation factors between spinel, diopside, pyrope, omphacite and forsterite at 

different temperatures and pressures by using our new method. Pressure effects of Mg and O 

isotopes of several silicate minerals are checked up to 13GPa (i.e., roughly the upper mantle 

condition). Very small but slowly increasing pressure effects on isotope fractionation between 

minerals are found with the increase of pressure. Besides, the fractionation factors between Mgbearing 

carbonates and aqueous Mg species are also calculated. There are large differences 

between the Mg isotope results of Rustad et al. (2010) ([1]) and Schauble (2011) ([5]). Our results 

are significantly different from both of them for the cases of solids vs. aqueous species. However, 

our results are close to newly determined fractionation factors by experiments. 

We re-check equilibrium Δi values of 13 C- 18 O clumps of several carbonate minerals: calcite, 

aragonite, dolomite, nahcolite and magnesite. Although our method is totally different from the 

method of Schauble et al. (2006) ([6]), our results generally agree with what Schauble et al. (2006) 

predicted. 

The tests of various isotope systems all show that the proposed method can provide reasonable 

results for isotopic fractionations of solids, especially this method is much better in producing 

isotope fractionation factors between solids and aqueous species than other methods. It therefore is 

an important method for providing precise equilibrium isotope fractionation parameters of solids. 

[1] Rustad et al. (2010) GCA, 74, 6301-6323. [2]Young et al. (2009) EPSL, 288, 524-533. [3] 

Li et al. (2011), EPSL, 304, 224-230. [4] Huang et al. (2010) GCA, 75, 3318-3334. [5] Schauble 

(2011) GCA, 75, 844-869. [6] Schauble et al. (2006) GCA, 70, 2510-2529. 

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THE 17 O ANOMALY IN DEEP OCEANIC DISSOLVED O 2 

Boaz Luz. The Institute of Earth Sciences, Hebrew University, Jerusalem 91904, Israel 

 

New measurements of 17 Δ [= ln(δ 17 O+1) – 0.518*ln(δ 18 O+1)] of dissolved O 2 in the deep Atlantic 

show surprising gradient from low values in the Sargasso Sea (31 o N) to high values in the Cape 

Basin (39 o S). I suggest that the high values in the south are remnant from the Little Ice Age when 

the North Atlantic had more extensive sea ice than today. 

From previous research we know that atmospheric O 2 has lower 17 O content than expected 

for O 2 of pure biological origin. This deficiency or 17 O anomaly is the result of mass independent 

fractionation in photochemical reactions in the stratosphere. When pure biological O 2 is formed by 

marine photosynthesis it has an excess of 17 O ( 17 Δ) with respect to air O 2 . 

Dissolved oxygen in seawater contains two types of O 2 , one which is derived from gas 

exchange with air O 2 with 17 Δ close to zero, and the other which is produced by photosynthesis in 

the ocean with 17 Δ of about 250 per meg. The 17 Δ of marine dissolved O 2 is a unique conservative 

tracer in the deep sea. It indicates marine formation of photosynthetic O 2 , but unlike O 2 

concentration, it is not affected by respiration and thus preserves the signature acquired at the 

photic zone in source regions from which subsurface water sinks. 

In the mixed oceanic surface layer 17 Δ is low due to rapid gas exchange with atmospheric 

O 2 (whose 17 Δ is by definition zero). Below the mixed layer, but still in the photic zone, gas 

exchange is attenuated by density stratification and 17 Δ has a maximum. At greater depth 17 Δ 

generally declines. For example, in the Sargasso Sea where the source region of deep water is the 

high latitude North Atlantic in winter, 17 Δ is low. The low 17 Δ indicates deep water formation in 

winter when illumination is low and high rate of air-sea gas exchange dominates. 

But the picture in the south is different and 17 Δ of deep water is high. The high 17 Δ of deep 

water there is surprising because at least part of it originates from the deep North Atlantic where 

we observed low 17 Δ. To explain this surprising observation, I suggest that water with very high 

17 Δ may be formed in cold oceanic regions if the ocean surface is covered by sea ice (It is well 

known that light penetrates through sea ice and phytoplankton within or below ice covered ocean 

produces O 2 by photosynthesis). If some seawater charged with such newly formed O 2 is entrained 

into sinking water it would explain the high 17 Δ in deep and bottom waters. At present the high 

latitude surface N. Atlantic in which deep water is formed is ice free. However during the Little 

Ice Age it was partially covered with sea ice and could produce deep water high in 17 Δ. 

Page 54


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ISOTOPIC SIGNATURES OF CO AND N 2 PHOTOLYSIS IN THE SOLAR NEBULA AND IN 

LABORATORY EXPERIMENTS 

J. R. Lyons, Earth & Space Sciences, UCLA, Los Angeles, CA, USA; jimlyons@ucla.edu 

One hypothesis for the origin of the CAI mixing line is photolysis of CO [1] – [3]. The reservoir of 

water produced from the O product is enriched in 17 O and 18 O relative to the bulk CO composition. 

Because C 16 O self-shielding is the dominant isotope effect during photolysis of an optically-thick 

column of CO gas, the water will have δ 17 O/δ 18 O ~ 1. This is true as long as the isotopic spectra 

exhibit line-type absorption features. For diffuse bands, in which the rotational lines are broadened 

and strongly overlapping, δ 17 O/δ 18 O < 1 will result [4], [5]. Because of this effect I obtain 

δ 17 O/δ 18 O ~ 0.9 for nebular water using simulated CO isotopic spectra in the solar nebula. The 

uncertainties in these simulated spectra are large, so the slope of 0.9 cannot be used to rule out the 

CO photolysis hypothesis. The shielding isotope effect is further modulated by isotope-dependent 

intensity variations in the absorption cross sections and the dissociation probability. This effect is 

important because it can alter the isotopic slope of the product O. Nevertheless, self-shielding is 

the dominant photon-driven isotopic process in astrochemical environments, and in laboratory 

experiments, despite the claims made by some authors [6], [7]. This is easily demonstrated by 

calculations simulating optically-thin gas columns [4], [5]. 

N 2 photolysis will yield similar isotope effects to those measured and computed for CO. 

Laboratory photolysis experiments on mixtures of N 2 and H 2 have demonstrated large enrichment 

of 15 N in the product NH 3 [8], suggesting that N 2 photolysis in the solar nebula (or parent cloud) 

could contribute to the ~ 400‰ enrichment seen in bulk nitrogen in terrestrial planets and 

meteorites versus the solar photosphere [9]. The 15 N enrichment is much larger than the 17,18 O 

enrichment relative to the Sun [10], suggesting that additional isotopic processes are required (e.g., 

[11]). Solar nebula models with a simplified H-C-N chemistry achieve substantial 15 N enrichment 

only for a strongly turbulent disk (a ~ 0.1). Preliminary simulations of N 2 laboratory photolysis 

experiments (N 2 /H 2 mixture) using coupled-channel cross sections for 28 N 2 and 29 N 2 [12] predict 

large enrichments in product NH 3 . Calculations for optically-thin N 2 gas columns yield isotope 

signatures < 100‰, even when using the coupled-channel cross sections, which fully account for 

intensity variations with nearby excited states. This again illustrates the dominant isotopic role of 

self-shielding. 

[1] Clayton, R. N. (2002) Nature 415, 860-861. [2] Lyons J. R. & E. D. Young (2005) Nature 435, 

317-320. [3] Lee, J. E. et al. (2008) MAPS 43, 1351-1362. [4] Lyons J. R. (2011), abstract, 42 nd 

LPSC, The Woodlands. [5] Lyons, J. R. (2012) MAPS, in prep. [6] Chakraborty, S. et al. (2008) 

Science 321, 1328-1331. [7] Chakraborty, S. et al. (2009) Science, 324, 1516d. [8] Chakraborty, S. 

et al. (2012), abstract, 43rd LPSC, The Woodlands. [9] Marty, B. et al. (2011) Science 332, 1533. 

[10] McKeegan, K. et al. (2011), Science 332, 1528. [11] Rodgers S. D. and Charnley S. B. (2008). 

MNRAS 385, L48. [12] Lewis, B. R, et al. (2011) N 2 photoabsorption cross sections in the vacuum 

ultraviolet, http://www.wellesley.edu/Physics/gstark/N2_ANU_cross_sections, Wellesley College, 

Wellesley, MA. 

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HIGH-RESOLUTION CROSS SECTIONS OF ISOTOPIC SO 2 AND IMPLICATIONS FOR ARCHEAN S- 

MIF 

J. R. Lyons 1 , D. Blackie ,2 , G. Stark 3 , J. Pickering 2 

1 Earth & Space Sciences, UCLA, Los Angeles, CA, USA; jimlyons@ucla.edu, 2 Physics 

Department, Imperial College, London, UK; 3 Physics Department, Wellesley College, Wellesley, 

MA, USA. 

The discovery of unusual sulfur isotope fractionation in Archean and Paleoproterozoic rocks has 

promised to yield insights into the rise of O 2 and the nature of the sulfur cycle on ancient Earth [1], 

but interpretation has been hampered by the lack of a clear mechanism for the sulfur isotope 

signature. Proposed mechanisms include SO 2 photolysis [1-4], mass-independent fractionation 

(MIF) during atmospheric S 3 (thiozone) formation, and thermal sulfate reduction in sediments [5]. 

Studies focusing only on SO 2 photolysis, including measurements of isotopic cross sections [6], 

have yielded results differing greatly from theory [4], and have resulted in improbable 

interpretations [7]. 

Here we report high-resolution ultraviolet cross section measurements of the sulfur isotopologues 

of SO 2 made with the UV FTS at Imperial College. This instrument has a dual-beam configuraton, 

allowing the D 2 lamp intensity to be monitored simultaneously with the gas absorption, effectively 

removing the lamp as a noise source. We measured cross sections at 1 cm -1 spectral resolution for 

32 SO 2 , 

33 SO 2 and 

34 SO 2 . Incorporating these cross sections into a simple atmospheric 

photochemical model, with a solar UV flux, yields sulfur MIF signatures for optically thin 

abundances of SO 2 due to small differences in the integrated cross sections. The Δ 33 S values for 

SO and S produced by photolysis of SO 2 and SO, respectively, are positive in the 190-220 nm 

range, in contrast to the results of lower resolution cross section measurements of [6]. We 

therefore do not need to invoke an additional absorber to modify the sign of the MIF signature, as 

was done using OCS in [7]. We find that additional MIF by self-shielding by 32 SO 2 places an 

upper limit on SO 2 of about 1 ppb. Our results imply that SO 2 photolysis alone is responsible for 

most of the Archean sulfur MIF record, and that sulfur MIF is a good proxy for the rise of O 2 in 

the earliest Paleoproterozoic. Work on 36 SO 2 is in progress. 

[1] Farquhar (2000) Science 289, 756-758. [2] Farquhar (2001) JGR 106, 32829-32840. [3] Pavlov 

& Kasting (2002) Astrobiology 2, 27-41. [4] Lyons (2007) GRL 34, L22811. [5] Watanabe et al. 

Science 324, 370-372. [6] Danielache et al. (2008) JGR 113, D17314. [7] Ueno et al. (2009) PNAS 

106, 14784-17789. 

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AN IMPROVED CEO 2 METHOD FOR HIGH PRECISION MEASUREMENTS OF OXYGEN ISOTOPE 

ANOMALY Δ 17 O OF ATMOSPHERIC CARBON DIOXIDE. 

Sasadhar Mahata 1 , S.K. Bhattacharya 1 , Chung-Ho Wang 2 and Mao-Chang Liang 1 

1. Research Centre for Environmental Changes, Academia Sinica, Nangang, Taipei, Taiwan, 

2. Institute of Earth Sciences, Academia Sinica, Nangang, Taipei, 

Taiwan 

The isotopic composition of carbon dioxide originating at the Earth’s surface is modified in the 

stratosphere by interaction with ozone which has anomalous oxygen isotope ratio (Δ 17 O = 

1000*ln(1+δ 17 O/1000) - 0.522*1000*ln (1+δ 18 O/1000) > 0). The inherited anomaly provides a 

powerful tracer for studying biogeochemical cycles involving CO 2 . However, the existing methods 

are not satisfactory to determine the small Δ 17 O variations found in the tropospheric CO 2 . In this 

work an earlier published CeO 2 and CO 2 exchange method (developed by Assonov and 

Brenninkmeijer) is modified and improved for measuring the triple oxygen isotope ratio of 

atmospheric carbon dioxide with high precision. 

The CO 2 fraction from air samples is separated by cryogenic means and purified using gas 

chromatography. This CO 2 is first analyzed in a MAT 253 mass spectrometer and then artificially 

equilibrated with hot CeO 2 to alter its oxygen isotopes in a mass dependent fashion and remeasured. 

From these data the 17 O/ 16 O and 18 O/ 16 O ratios are calculated. The procedure is able to 

determine Δ 17 O of CO 2 with an analytical precision of ±0.1‰. 

The validity of the method has been confirmed through several tests by using artificially made CO 2 

with zero and non-zero Δ 17 O. A limited number of atmospheric CO 2 samples have been analyzed 

from Taiwan which is influenced by monsoonal wind systems. In addition, the published value of 

CO 2 - H 2 O equilibrium exchange slope has also been confirmed by this method. 

Page 57


ISI 2012: 18- 22 June 2012 



VARIABILITY IN ISOTOPE RATIOS OF NITROGEN AND OXYGEN IN NITROUS OXIDE OF AIR 

OVER THE PACIFIC 

Sasadhar Mahata , Cheng-Ting Lin, Danie Liang, and S. K. Bhattacharya 

Research Centre for Environmental Changes, Academia Sinica, Taipei 11529, Taiwan R.O.C. 

Email: wilson181085@gate.sinica.edu.tw 

Taiwan is located in an interesting climatic zone where several monsoon systems meet 

bringing varying amount of three air masses: Tropical Maritime air from Northern Pacific, 

Equatorial Maritime air from South China Sea and Polar Continental air from Asian Continent. 

Samples of air in different seasons should carry signatures of these three regions especially in 

isotope ratios of trace gases. With this aim, we have initiated a project to measure isotope ratios of 

nitrogen and oxygen in nitrous oxide in Taiwan during various seasons. We report here 

preliminary results of such analyses over the transition period from Equatorial Monsoon to Winter 

Monsoon in 2011. Samples of air were collected in December, 2011 from Keelung area in North 

East Taiwan from a location near the sea in glass flasks. The flasks were flushed with air (passing 

through Ascarite) and filled up to a pressure ~1.5 times the ambient level (corresponding to ~7 

nmole of N 2 O) by using a compressor. We used a Conflow system associated with Thermo 

Finnigan mass spectrometer. The N 2 O fraction was passed through a GC column to separate any 

residual CO 2 . The working standard was a Tank N 2 O calibrated earlier using oxygen and nitrogen 

standards provided by OZTECH (δ 18 O: 27.54 ‰ rel to VSMOW and δ 15 N:-0.53 ‰ rel to Air). The 

reproducibility of the analysis is estimated to be 0.1 ‰ for both the isotope ratios. 

The average δ 15 N value is 7.0±0.3 ‰ (rel to Air) and the average δ 18 O value is 43.5±0.3‰ (rel to 

SMOW). These can be compared to the values obtained by Kaiser et al (2003) in samples from six 

locations of Germany during 1999. The mean values are: 6.7 ‰ and 44.6 ‰ respectively. The 

Keelung 15 N/ 14 N ratios are slightly higher (by about 0.3‰) while corresponding 18 O/ 16 O ratios are 

slightly lower (by about 1.1‰). No clear variation due to onset of Winter Monsoon can be 

detected as yet. 

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PHOTOCHEMICAL ISOTOPE EFFECTS IN SNOWPACK NITRATE 

Carl Meusinger 1 , Tesfaye A. Berhanu 2 , Joseph Erbland 2 , Florent Dominé 2 , Joël Savarino 2 and 

Matthew S. Johnson 1 

1 

Copenhagen Center of Atmospheric Research, Department of Chemistry, University of 

Copenhagen, Denmark, came@kiku.dk; 2 Laboratoire de Glaciologie et Géophysique de 

l'Environnement, St Martin d'Heres, France 

Sunlight is known to change snowpack nitrate concentrations, but the specific mechanisms are not 

well characterized preventing the recovery of historical nitrate concentrations. Studies of isotope 

distributions can distinguish specific processes, potentially giving a powerful tool for interpreting 

the records. In particular, the quantum yield of nitrate photolysis and the reformation of nitrate 

from its photolysis products are in need of further study. 

We present measurements of nitrate concentration changes and the accompanying N and O 

isotopic fractionations resulting from experiments performed using Antarctic snow illuminated by 

a Xe lamp. The snow was typically irradiated for several days at -30 °C and flushed at 1 l/min with 

N 2 to remove gas-phase photolysis products. The N 2 stream was at 100 % relative humidity to 

prevent physical changes of the snow, which was confirmed by measurements of the snow specific 

surface area. After illumination the snow column was treated like an ice core and cut into slices 

that were melted and analyzed using Liquid Chromatography and Isotope Ratio Mass 

Spectrometry employing the bacteria method. 

The δ 15 N data shows no typical 

Rayleigh behavior but levels off, 

showing no stronger enrichment 

then ~7 ‰ (on top of the initial 

34 ‰). With a second process 

present, different mixing scenarios 

can be employed to interpret these 

profiles. The triple O isotope data 

shows trends similar to those 

observed in field campaigns 

indicating a loss of the initial mass 

independent signal. 

Altering the flow direction, and 

therefore presumably the location 

of reformed nitrate does not change the profiles of nitrate concentration and isotopes. In order to 

quantify the second process, the photon flux inside the snow was measured to model the changes 

in nitrate concentration due to photolysis only. This allows further to constrain present 

uncertainties on the quantum yield of the photolysis of nitrate in snow. 

Page 59


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13-CARBON ISOTOPIC FRACTIONATION IN SECONDARY ORGANIC AEROSOL FORMATION 

C. Meusinger 1 , U. Dusek 2 , S.M. King 1 , M. Bilde 1 , Thomas Röckmann 2 and M.S. Johnson 1 . 1 

Copenhagen Center of Atmospheric Research (CCAR), Department of Chemistry, University of 

Copenhagen, 2100, Denmark, came@kiku.dk; 2 Institute for Marine and Atmospheric research 

Utrecht (IMAU), Utrecht University, 3584 CC, The Netherlands 

Secondary organic aerosol (SOA) formed by oxidation of volatile organic compounds (VOC) is a key 

field of atmospheric research since its significant impacts on climate, health and visibility are not well 

understood. Given the vast number of reactions involved in the oxidation of VOCs, reaction 

mechanisms are unclear and SOA yields are uncertain. The general goal of this project is to use isotope 

ratios to distinguish reaction pathways as they alter the isotopic composition of products and reactants 

in a unique way via the kinetic isotope effect (KIE). This in turn helps establish chemical reaction 

schemes and constrain budgets. Studies using isotopes cover a wide range, e.g. atmospheric samples, 

gas-phase reactions and SOA generation. 

The specific goal of this project is to investigate the link between 13 C fractionation and oxidation state 

in organic aerosols. This study is a first step and aims to provide insight into SOA formation using 

stable carbon isotopes. Starting from precursors with natural isotopic abundance, aerosols are created in 

chamber experiments by nucleation, i.e. without seeds present, and oxidation by ozone. The resulting 

SOA is collected on pre-treated quartz filters and analyzed for its carbon isotopic composition ( 13 C & 

12 C.) Results are presented for the following systems: 

1) Glutaric acid aerosol generated using an 

atomizer and deposited on a filter 

immediately after drying. 

2) SOA from α-pinene ozonolysis created in the 

steady-state chamber (OH scavenger 1- 

butanol). 

3) SOA from α-pinene ozonolysis created in the 

steady-state chamber (OH scavenger 

cyclohexane). 

 

System and filter (handling) blanks were included in 

the study. Experiment 1 was compared to combustion 

of pure glutaric acid to see the difference due to the filters. 

The (dark) chamber experiments are carried out in the new 5 m 3 temperature controlled continuous 

flow chamber at the Copenhagen Center for Atmospheric Research. The chamber is designed to operate 

at steady state, i.e. at constant experimental conditions set to resemble a specific reaction state (‘fresh’ 

versus ‘aged’ aerosol.) SOA particle-size distributions are monitored continuously along with SOA's 

ability to act as a cloud condensation nucleus to compare with previous studies. 

Filter samples were analyzed at the Institute for Marine and Atmospheric Research Utrecht using 

Isotope Ratio Mass Spectrometry. Here, the filters are heated stepwise (100-390 °C) in He to evaporate 

organic compounds that are subsequently converted to CO 2 for the isotope analysis. 

The setup will be presented in detail, along with first results and possible implications of the 

findings. 

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INVESTIGATING THE POSSIBILITY OF A HYPERFINE COUPLING (‘MAGNETIC ISOTOPE 

EFFECT’) MECHANISM FOR THE NON-MASS-DEPENDENT FRACTIONATION OF OXYGEN 

ISOTOPES CAUSED BY THERMAL DECOMPOSITION OF DIVALENT METAL CARBONATES 

M. F. Miller 1,2 , A. L. Buchachenko 3 , E. Bailey 4,5 , P. F. McMillan 4 , and M. H. Thiemens 6 . 1 British 

Antarctic Survey, High Cross, Madingley Road, Cambridge CB3 0ET, UK (mfm@bas.ac.uk), 

2 Planetary and Space Sciences, The Open University, Walton Hall, Milton Keynes MK7 6AA, UK, 

3 N. N. Semenov Institute of Chemical Physics, Russian Academy of Sciences, Moscow 119991, 

Russia, 4 Department of Chemistry, University College London, 20 Gordon Street, London WC1H 

0AJ, UK, 5 Max-Planck Institute for Solid State Research, Heisenbergstraβe 1, D-70569 Stuttgart, 

Germany, 6 Department of Chemistry and Biochemistry, University of California San Diego, 9500 

Gilman Drive, La Jolla, CA 92093-0356, USA 

There are few documented occurrences of non-mass-dependent isotopic fractionation being 

generated by a physical or chemical reaction which does not involve photochemical mediation and 

gaseous reactants. Recent examples include the generation of anomalous 17 O distributions by 

application of a thermal gradient (Sun and Bao 2011a, 2011b), and anomalous 33 S distributions 

during thermochemical sulfate reduction (Watanabe et al., 2009; Oduro et al., 2011). In such cases, 

it has been postulated that the ‘magnetic isotope effect’ is likely to be implicated. This occurs 

when the lifetime of a radical pair is sufficient for hyperfine coupling between ‘magnetic’ nuclei 

(i.e. those of non-zero nuclear spin) and unpaired electrons to influence interconversion between 

singlet and triplet states. Such coupling changes the proportion of reactive intermediates that can 

participate in spin-selective reactions. A decade ago, it was shown that thermal decomposition of 

calcium carbonate (under vacuum conditions, to minimize the potential for back-reaction and 

oxygen isotope exchange between the CaO and CO 2 formed) produces anomalous depletion of 17 O 

in the solid oxide and an equivalent enrichment of 17 O in the CO 2 . No explanation was offered for 

how the non-mass-dependent isotopic fractionation might occur. It was found subsequently that 

thermal decomposition of other divalent metal carbonates gives a similar result, and that 

performing the decomposition in a strong magnetic field (~0.25T) has no effect on the oxygen 

isotopic composition of the reaction products (Miller, unpublished). We are currently testing 

empirically the possibility that a hyperfine coupling mechanism (proposed by ALB) is responsible 

for the observed isotopic findings. To do this required high pressure synthesis of a carbonate 

which was first demonstrated to exist as recently as 1973. Thermal decomposition of this reagent 

should not produce a 17 O anomaly, if the proposed mechanism is correct. Further information, and 

a progress report, will be presented at the conference. 

Miller M. F., Franchi I. A., Thiemens M. H., Jackson T. L., Brack A., Kurat G. and Pillinger C. T. (2002) 

Mass-independent fractionation of oxygen isotopes during thermal decomposition of carbonates. 

Proc. Nat. Acad. Sci. U.S.A. 99, 10988–10993. 

Oduro H., Harms B., Sintim H. O., Kaufman A. J., Cody G. and Farquhar J. (2011) Evidence of magnetic 

isotope effects during thermochemical sulfate reduction. Proc. Nat. Acad. Sci. U.S.A. 108, 17635– 

17638. 

Sun T. and Bao H. (2011a) Non-mass-dependent 17 O anomalies generated by a superimposed thermal 

gradient on rarefied O 2 in a closed system. Rapid Commun. Mass Spectrom. 25, 20–24. 

Sun T. and Bao H. (2011b) Thermal-gradient-induced non-mass-dependent isotope fractionation. Rapid 

Commun. Mass Spectrom. 25, 765–773. 

Watanabe Y., Farquhar J. and Ohmoto H. (2009) Anomalous fractionations of sulfur isotopes during 

thermochemical sulfate reduction. Science 324:370–373. 

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LASER BASED N 2 O ISOTOPOMER ANALYSIS BRIDGES THE GAP BETWEEN PURE CULTURE 

STUDIES AND FIELD APPLICATIONS 

J. Mohn 1 , P. Wunderlin 2 , B. Tuzson 1 , H. Siegrist 2 , A. Joss 2 , L. Emmenegger 1 . 1 Empa, Laboratory 

for Air Pollution & Environmental Technology, CH-8600 Dübendorf, Switzerland, 

joachim.mohn@empa.ch, 2 Eawag, Process Engineering, CH-8600 Dübendorf, Switzerland 

Nitrous oxide (N 2 O) is the most important anthropogenically emitted ozone depleting 

substance and a significant greenhouse gas. Target-oriented reduction strategies require the 

identification of the main transformation processes. A powerful technique is the analysis of the 

intramolecular distribution of 15 N in the non-symmetric N 2 O molecule [1]. Recent advances in quantum 

cascade laser absorption spectroscopy enable the direct and highly precise quantification of the 15 N 

structural isomers (isotopomers) of nitrous oxide 14 N 15 NO ( 15 N a ) and 15 N 14 NO ( 15 N b ), simultaneously 

with 14 N 14 NO [2, 3]. 

In the present study we investigated the isotopic signature of distinct microbial N 2 O production 

and consumption pathways in a laboratory scale batch reactor filled with municipal wastewater [4]. 

Specific microbial pathways were favored by selection of the nitrogen substrate (NH 2 OH, NO 2 - , NH 4 + , 

NO 3 - ) and the process conditions. For the different microbial N 2 O production pathways we observed 

significantly different site-selective isotopic signatures: Δδ 15 N was considerably higher for nitrification 

(43.5 to 58.8 ‰) as compared to denitrification (0.1 to 19.5 ‰). Furthermore, the site preference can be 

employed to trace the N 2 O reductase activity and to differentiate between the contribution of nitrifier 

denitrification by ammonium oxidizing bacteria or NH 2 OH oxidation. Results from our experimental 

study are in accordance with pure culture studies [5 and references therein] and can therefore be 

applied to other ecosystems. 

Several environmental studies employing laser spectroscopy will be discussed, including the first 

example of continuous site specific analysis of N 2 O isotopic species at ambient mixing ratios above 

pristine and fertilized soils [Figure, 6]. 

8 

δ 15 N bulk [‰] 

SP [‰] 

N 2 O [ppb] 

4 

0 

-4 

20 

18 

16 

14 

12 

480 

440 

400 

360 

320 

9 

7 

δ 15 N bulk [‰] 

5 

20 

SP [‰] 

19 

18 

340 

N 2 O [ppb] 

330 

320 

10.09.2010 12.09.2010 14.09.2010 

fertilization 

10.09.2010 15.09.2010 20.09.2010 25.09.2010 30.09.2010 

date & time 

[1] Toyoda, S and Yoshida, N (1999) Anal. Chem. 71, 4711. [2] Wächter H, Mohn J, Tuzson B, 

Emmenegger L, Sigrist MW (2008) Opt. Express 16: 9239. [3] Mohn J, Guggenheim C, Tuzson B, Vollmer 

MK, Toyoda S, Yoshida N, Emmenegger L (2010) Atmos. Meas. Tech. 3: 609. [4] Wunderlin, P; Mohn, J; 

Joss, A; Emmenegger, L; Siegrist, H (2012) Water Res. 46, 1027. [5] Yamagishi, H; Westley, MB; Popp, 

BN; Toyoda, S; Yoshida, N; Watanabe, S; Koba, K; Yamanaka, Y (2007) J. Geophys. Res 112, G02015. [6] 

Mohn, J; Tuzson, B; Manninen, A; Yoshida, N; Toyoda, S; Brand, WA; Emmenegger, L (2012) Atmos. 

Meas. Tech. Discuss. doi:10.5194/amtd-5-813-2012. 

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TRIPLE OXYGEN ISOTOPE ANALYSIS OF N 2 O USING MICROWAVE DISCHARGE 

DECOMPOSITION METHOD 

Arata Mukotaka 1 , Sakae Toyoda 2 , Naohiro Yoshida 1 , Reinhard Well 3 

1 Department of Environmental chemistry and Engineering, Tokyo Institute of technology, Japan, 

mukotaka.a.aa@titech.ac.jp 

2 Department of Environmental science and Technology, Tokyo Institute of technology, Japan 

3 Institute of Agricultural Climate Research, Thünen-Institute, Germany 

Tropospheric and lower stratospheric N 2 O shows a 17 O excess, i.e. 17 O = 0.9±0.1‰ [Cliff and 

Thiemens 1997; Cliff et al., 1999; Kaiser et al., 2003]. Proposed mechanisms of the 17 O excess 

are atmospheric reactions like NH 2 + NO 2 , N 2 O + O( 1 D) [Kaiser and Röckmann, 2005], and N 2 O 

in the middle or upper stratosphere might have larger 17 O value than in the troposphere and 

lower stratosphere. 

On-line analytical system using thermal decomposition method to measure the triple oxygen 

isotope of N 2 O has been developed by Kaiser et al. [2007] and Komatsu et al. [2008] and the 

latter achieved the precision of 0.20‰ with more than 20 nmol of N 2 O. However, it is not still 

enough to measure the 17 O value in middle or upper stratospheric N 2 O with high precision. 

In this study, we developed a novel on-line method using microwave discharge to decompose 

N 2 O to N 2 and O 2 . Moreover, this method has been applied to measurements of the 17 O value of 

nitrate with the aid of denitrifier that converts nitrate to N 2 O. 

First, N 2 O was introduced into an analytical system that consists of N 2 O purification unit, 

microwave discharge unit, O 2 purification unit and the isotope ratio mass spectrometer (Finnigan 

MAT 252). Purified N 2 O was decomposed to N 2 and O 2 by microwave discharge using 

Beenakker cavity (Opthos Instrument, Inc.), and produced O 2 was purified by gas 

chromatography (Molsieve 5A). The 17 O excess is defined by following equation, 17 O = 

(1+ 17 O) / (1+ 18 O) - 1 and is 0.516 [Kaiser et al., 2004]. 

The yield of O 2 produced by decomposition of N 2 O was more than 90 % and byproducts such 

as NO and NO 2 were not detected. Although sample size dependence of the 17 O value was 

observed with less than 17 nmol of N 2 O and its trend was slightly different from day to day, the 

precision (n = 5, 1) was better than 0.3‰ with more than 28 nmol of N 2 O. 

For nitrate, the precision (an average of the difference of twice measurements in each sample 

size) was better than 0.3‰ with more than 55 nmol of nitrate and sample size dependency was 

corrected using international standards (USGS34 and USGS35). 

The advantage of this method is that high precision analysis of the 17 O of N 2 O and nitrate can 

be obtained without removing the water and VOC. 


Cliff S.S. and Tiemens M.H. (1997) Science, 278, 1774-1776. 

Cliff S.S., Brennkinkmeijer C.A.M. and Tiemens M.H. (1999) J. Geophys. Res.-Atmos., 104, 

16171-16175. 

Kaiser J., Röckmann T. and Brenninkmeijer C.A.M. (2003) J. Geophys. Res., 108(D15). 

Kaiser J., Röckmann T. and Brenninkmeijer C.A.M. (2004) J. Geophys. Res., 109(D03305). 

Kaiser J., Röckmann T. (2005) Geophys. Res. Lett., 32(15). 

Kaiser J., Hastings G., Houlton B. A., Rockmann T. and Sigman D. M. (2007) Anal. Chem. 79, 

599-607. 

Komatsu D., Ishimura T, Nakagawa F. and Tsunogai U. (2008) Rapid Commun. Mass Spectrom. 

22, 1587-1596. 

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13 C/ 12 C OF THE VOLATILE COMPOUNDS AND THEIR RELATION TO THE ENVIRONMENTAL 

VARIATION BASED ON THE GC-IRMS ANALYSES 

Ariaki Murata, 1 Uli Engelhardt, 2 Peter Winterhalter, 2 Keita Yamada, 3 Naohiro Yoshida, 3 Naoharu 

Watanabe 1 . 1 GSST, Shizuoka Univ. e-mail: murata_ariaki@yahoo.co.jp, 2 TInstitute Food Chem., 

Braunschweig University, Technology, 3 Tokyo Insti. Technol. Envir. Chem. 

Carbon isotope ratio 13 C/ 12 C (δ 13 C) are characteristic of the terrestrial ecosystems. The values 

of δ 13 C are useful for the authenticity control of crops. The combustion of whole target crop 

samples (bulk) gives characteristic δ 13 C signature of the production area, whereas they may also 

lead to ambiguous results due to the presence of tremendous types of metabolites in different 

proportions in each crop grown under the varying environmental conditions. 

δ 13 C of each metabolite is based on the isotopic fractionation of biosynthetic or enzymatic 

pathways. δ 13 C of secondary metabolites in a single plant variety are reflected by the 

environmental differences, such as the growth area . The major factor is CO 2 concentration Pi/Pa 

1) . The second is a relative value of water stress to salt stress toward the plant. To clarify if the 

difference in δ 13 C would be observed for the secondary metabolites produced by a single plant 

variety grown in various areas, we analyzed several volatile compounds accumulated in green tea 

(Camellia sinensis var. Yabukita) leaves. Several glycoconjugates of 2-phenylethanol, 

benzylalcohol, and (Z)-3-hexenol were isolated from the green tea leaves grown in several areas in 

Japan and China. The volatile compounds obtained after the enzymatic hydrolysis, were subjected 

to the isotope ratio analysis comprising an online combustion linked to gas chromatograph (GC- 

IRMS). In addition, we performed bulk analysis of green tea leaves as the comparison studies to 

the compound-based analysis. 

We clarified the compound-based analysis showed larger differences in δ 13 C than the bulk 

analysis among the several growth areas. Moreover δ 13 C were different in each compound 

accumulated in the green tea leaves grown in even a single area, i.e., δ 13 C of 2-phenylethanol, 

benzylalcohol, and (Z)-3-hexenol ranged from -26.40 to -28.40‰ , -36.55 to -28.80‰, and -31.69 

to -28.49‰, respectively, whereas the bulk δ 13 C values were from -28.28 to -25.82‰. The new 

method exhibited characteristic values of 13 C/ 12 C to each green tea sample, enabling differentiation 

of the growth areas. 

Hydrolysis 

GC-IRMS 

analysis 

Glycoconjugates 

(ex. Primeverosides) 

of volatile alcohols 

Volatile compounds 

1) Farquhar, G. D.; O’Leary, M. H.; Berry, J. A. Aust. J. Plant Physiol. 1982, 9, 121-137. 

Page 64


ISI 2012: 18- 22 June 2012 



CHANGES IN THE Δ 18 O OF RECENTLY ALTERED CARBONATES: WATER OR TEMPERATURE? 

S.T. Murray 1 , M.M. Arienzo 1 , Y. Hernawati 1 , P.K. Swart 1 

1 Division of Marine Geology and Geophysics, Rosenstiel School of Marine and Atmospheric 

Sciences, University of Miami, Miami FL 33149; email: smurray@rsmas.miami.edu 

A series of cores were taken between two prograding Pleistocene reef terraces at 30m and 

15m elevation above sea level from Boca Chica in southern Dominican Republic. These cores 

have been used to study the application of the clumped isotope method during carbonate 

diagenesis. The δ 13 C and δ 18 O of these cores, which are now predominantly calcite, were 

measured in order to gain insight into the effects of multiple stages of meteoric diagenesis, 

exposure, and sea-level changes over the past 1.8 million years (Hernawati et al., 2011). The 

samples show evidence of meteoric vadose diagenesis being overprinted by meteoric phreatic 

diagenesis during sea-level low stand/high stand transitions. Because of varying lengths of 

exposure time, the two terraces vary isotopically as a result of the effects of diagenesis. This is 

supported by the δ 13 C and δ 18 O data which show two separate inverted-J meteoric calcite lines 

(Lohmann, 1988) within the 15m terrace separated by 1‰ in δ 18 O while the 30 m terrace presents 

more uniform δ 18 O values throughout. Core locations on both terraces were described as back-reef 

environments. The correlation of environment but varying isotopic values allowed Hernawati et al. 

to conclude that length of exposure to separate water masses caused varying isotopic values (2011). 

We have applied the clumped isotope technique to the samples from the Dominican 

Republic to suggest an alternative, temperature-based, theory for the multiple-meteoric calcite 

lines. We have found evidence that a singular water-mass at varying temperatures can produce the 

isotopic variation seen in the δ 18 O of the carbonates. This does not rule out the influence of 

exposure times, multiple water masses, and diagenetic alteration, but suggests another possible 

route to reach a similar conclusion. 

Hernawati, Yulaika, "Meteoric Diagenesis of Plio-Pleistocene Reef Terraces in the 

Southern Dominican Republic" (2011). Open Access Theses. Paper 296. 

http://scholarlyrepository.miami.edu/oa_theses/296 

Lohmann, K. C., 1988, Geochemical patterns of meteoric diagenetic systems and their application 

to studies of paleokarst. In: N. P. James, and P. W. Choquette (Eds.), 

Paleokarst. Springer-Verlag, New York, pp. 58−80. 

Page 65


ISI 2012: 18- 22 June 2012 



QUADRUPLE SULFUR ISOTOPIC SYSTEMATICS OF ANOXYGENIC PHOTOSYNTHESIS AND 

SULFATE REDUCTION IN LOW SULFATE CONCENTRATION CONDITION 

Mayuko Nakagawa 1 , Yuichiro Ueno 1 , Naohiro Yoshida 1 

1 Tokyo Institute of Technology, Japan: nakagawa.m.ae@m.titech.ac.jp 

Sulfur redox cycling is important for anaerobic aquatic ecosystem. The sulfate supplied to 

such a condition is generally converted into sulfide by microbial sulfate reduction. When sulfidic 

conditions develop in the photic zone, anoxygenic phototrophs actively fix carbon through 

oxidation of sulfide, resulting in higher primary productivity than that observed under oxic 

conditions. These two biological processes drive the anoxic sulfur cycle in stratified lakes and also 

in the Precambrian ocean. 

Recently, quadruple sulfur isotope system ( 32 S/ 33 S/ 34 S/ 36 S) has been focused, because it 

provides a way to distinguish the signatures of different sulfur metabolisms, even when δ 34 S 

fractionations are identical (Ono et al., 2006). The capital delta notations of less abundant isotopes 

show minor deviation from mass-dependent fractionation. And we also use ‘l’ to express observed 

mass-dependent fractionation in logarithmic form. These quadruple sulfur values have a potential 

of a new tracer not only for photochemically-induced non-mass-dependent reactions, but also for 

mass-dependent processes including biogeochemical reactions (Farquhar et al.,2003; Johnston et 

al., 2007). 

We have studied sulfur isotope ratios of sulfate and sulfide in a small monomictic lake, 

Fukami-ike, central Japan, having a maximum depth of 8.0 m. The lake is eutrophic and is 

stratified from April to November, when green and purple sulfur bacteria (anaerobic 

photosynthesizer) are active at oxic-anoxic boundary layer, and sulfate reducing bacteria produces 

hydrogen sulfide accumulated in an anoxic hypolimnion (Yagi 1996). The seasonal change of 

sulfur cycle in co-existent system including microbial sulfate reduction and anoxygeic 

photosythesis has been investigated from 2007 to 2009. The minor sulfide isotope ratios (Δ 33 S and 

Δ 36 S) in water column of the lake showed larger values than those produced by sulfate reduction 

only. Numerical simulation indicates the observed sulfide isotopic values reflect the relative 

contribution of anoxygeic photosynthesis to sulfate reduction. Furthermore, we will discuss how 

the isotopic signature of such a co-existent system can be preserved in the sedimentary sulfide 

minerals. 


Farquhar, J., Johnston, D. T., Wing , B., Habicht, K., Canfield, D., Airieau, S., Thiemens, M., 

(2003), Multiple sulfur isotopic interactions of biosynthetic pathways: implications for 

biological signatures in the sulfur isotope record. Geology 1, 27-36 

Johnston, D. T., Farquhar, J., Canfield, D. E., (2007), Sulfur isotope insights into microbial sulfate 

reduction: When microbes meet models. Geochimica Et Cosmochimica Acta., 71 (16), 3929- 

3947 

Ono, S., Wing, B., Johnston, D., Farquhar, J. and Rumble, D (2006), Mass-dependent fractionation 

of quadruple stable isotope system as a new tracer of sulfur biogeochemical cycles, Geochimica 

et Cosmochimica Acta, 70, 2238-2252 

Yagi, A (1996), Manganese flux associated with dissolved and suspended manganese forms in 

Lake Fukami-ike, Water Research., 30 (8), 1823-1832. 

Page 66


ISI 2012: 18- 22 June 2012 



PHOTODISSOCIATION DYNAMICS OF SO AND SO 2 

S. Nanbu 1 , T. Suzuki 1 , A. D. Kondorskiy 2 , I. Tokue 3 , S. O. Danielache 4 , Yuichiro Ueno 4 . 1 Sophia 

Univ., Japan, , 2 Lebedev Phys. Inst., 3 Niigata Univ., 4 Tokyo Inst. of 

Tech. 

Isotope effects produced during the excited-state dynamics were theoretically studied for Sulfur 

monoxide (SO) and Sulfur dioxide (SO 2 ). Photodissociation cross sections were computed using two 

methods; R-matrix theory was employed to solve the close-coupling equations in 1D system, while wave 

packet dynamics was used in the 3D system. Energy surfaces were calculated at multi-reference correlation 

interaction (MRCI) method with augmented correlation consistent polarized valence sextuple-z (aug-ccpV6Z) 

basis set for SO and aug-cc-pVTZ for SO 2 by Woon and Dunning. The six lower-lying electronic 

states were explored in SO, while the five states were considered for SO 2 . It is found that both systems have 

a pseudo-crossing between electronic excited states, which would cause non-adiabatic phenomena. In order 

to take account for the non-adiabatic effect, non-adiabatic coupling matrix elements (NACME) were 

computed in the 1D (3D) coordinates of SO (SO 2 ). In particular, the diabatic representation was used in the 

3D dynamics; the full Hamiltonian is given by equation 1 and the real wave packet approach (Chebyshev 

order expansion) was employed. 

Hˆ 

s 

ˆ s ˆ s 

⎛⎛H11 H ⎞⎞ 

12 

= ⎜⎜ ⎟⎟ 

⎜⎜ ˆ s ˆ s 

H21 H ⎟⎟ 

⎝⎝ 

22 ⎠⎠ 

⎛⎛( Vˆ ˆ ˆ 

11 

+ H ) 

ˆ 

trans 

+ Hrot as + bs aV ⎞⎞ 

s 12 

= ⎜⎜ 

⎟⎟ 

⎜⎜ aVˆ 12 ( 

ˆ ˆ ˆ 

s 

V22 

+ Htrans + Hrot ) as + b 

⎟⎟ 

s 

⎝⎝ 

⎠⎠ 

The diabatic potentials V 11 , V 12 , and V 22 were determined by the adiabatic potentials E 11 , E 22 , and the mixing 

angle b given by the NACME calculation. 

Vˆ = E cos β + E sin β 

2 2 

11 11 22 

Vˆ = E sin β + E cos β 

2 2 

22 11 22 

Vˆ = ( E −E 

)cos βsin 

β 

12 22 11 

Figure 1 shows the preliminary result of SO 2 photodissociation cross section comparing with the 

result without the non-adiabatic effects. We clearly see the difference between these two results. We will 

present and discuss the details of the photodissociation mechanism of SO and SO 2 . 

(1) 

Fig. 1 Comparison of calculated spectra of SO2 with and without non-adiabatic effects. 

Page 67


ISI 2012: 18- 22 June 2012 



SELF-SHIELDING AND MOLECULAR DYNAMICS ORIGINS OF SULFUR MASS-INDEPENDENT 

FRACTIONATION DURING SO2 UV PHOTOCHEMISTRY 

Shuhei Ono, Andrew R. Whitehill, Harry D. Oduro, Department of Earth, Atmospheric, and 

Planetary Sciences, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, 

MA 02139 sono@MIT.EDU. 

Laboratory photochemical studies have shown that SO 2 photochemistry produces sulfur 

mass-independent isotope fractionation (S-MIF) (Farquhar et al., 2001; Masterson et al., 2011) but 

the origin of S-MIF is poorly understood. In order to gain mechanistic understanding of the 

production of S-MIF, a series of laboratory SO 2 photolysis are carried out using broadband light 

sources (Xe and D arc lamps). The flow-through reactor allows us to test the magnitude and 

pattern of S-MIF as a function of pSO 2 and pN 2 . A series of bandpass, longpass, and shortpass UV 

filters are used to isolate the regions of UV spectrum to test the sensitivity on the UV spectrum. 

Dual-cell experiments are carried out to test the effect of isotopologue self-shielding. 

Photolysis of SO 2 with a Xe arc lamp source produces SO 3 and S 0 aerosols, which are 

analyzed for sulfur isotope ratios along with residual SO 2 . Although SO 2 excitation in the 240 to 

350 nm region occurs, the low-energy excited states are rapidly quenched by collision with N2 

before participating in chemical reactions. The product S 0 yield large δ 34 S values of up to 140 ‰, 

with relatively constant δ 33 S/δ 34 S ratios of 0.60±0.04. The magnitude of the isotope effect 

correlates with pSO 2 , suggesting the critical importance of isotopologue self-shielding in the 190 

to 220 nm region. The model calculation using shifted-cross section by Lyons (2007) shows 

qualitative agreement with the experimental data. Potential effects of molecular dynamics (e.g., 

non-adiabatic surface crossing, Zmolek et al.,1999) or isotopologue dependent cross section 

amplitude (Danielache et al., 2008) will be discussed. 

In contrast, experiments targeting the photochemistry of 240 to 330 nm region (1A2, 

1B1←1A1) produce S-MIF patterns and pSO2 dependence different from those under 190 to 220 

nm regions. This suggests the significance of molecular dynamics for S-MIF production in this 

excitation band system, and will be discussed by the accompanying abstract by Whitehill, Oduro 

and Ono (this volume). 

References cited: 

Danielache, S.O. et al., J. Geophy. Res. 113, 1-14 (2008). 

Farquhar, J. et al., J. Geophys. Res 106, 32829–32 (2001). 

Lyons, J.R., Geophy. Res. Lett. 34, 1-5 (2007). 

Masterson, A.L. et al., Earth Planet. Sci. Lett. 306, 253-260 (2011). 

Whitehill, Oduro, Ono, ISI2012 abstract 

Zmolek, P. et al, J. Phys. Chem. A 103, 13-16 (1999). 

Page 68


ISI 2012: 18- 22 June 2012 



THE ENIGMATIC NITROGEN BIOGEOCHEMISTRY OF LAKE VIDA, AN ISOLATED BRINE 

CRYOECOSYSTEM 

Nathaniel E. Ostrom 1 , Alison E. Murray 2 , Gareth Trubl 2 , Emanuele Kuhn 2 . 1 Department of 

Zoology, Michigan State University, East Lansing MI 48824-1115, USA, ostromn@msu.edu; 2 

Division of Earth and Ecosystem Sciences, Desert Research Institute, Reno NV, USA 

Lake Vida, in the Victoria Valley of East Antarctica harbors, ice-entrained brine (20% salt, > 6 

times seawater) that has been isolated from the surface for several thousand years. The brine conditions 

(permanently dark, temperature of -13.4 °C, lack of oxygen, and pH of 6.2) and geochemistry are 

highly unusual. As an example, the brine contains the highest concentrations of N 2 O reported for any 

aquatic ecosystem (86.6 mM) and exceptionally high levels of NH 4 + (3.9 mM), NO 3 - (0.9 mM) and 

NO 2 - (23.7 mM). Though this cryoecosystem appears to be relatively inhospitable, microbial life is 

abundant (cell levels over 10 7 cells per mL), is capable of protein production at in situ temperatures, 

and harbors a unique, but not necessarily novel, assemblage of bacterial phylotypes spanning at least 

eight phyla. 

To assess in situ present and past microbial activity, and test hypotheses concerning energy 

generation in the brine cryoecosystem, the stable isotope signatures of nitrogen, oxygen, and hydrogen 

have been characterized in liquid and dissolved gas phases. The isotopic compositions of nitrate (δ 15 N 

= -7.9 ‰, δ 18 O = 31.7 ‰), ammonium (δ 15 N = -4.8 ‰) and dinitrogen (δ 15 N = 0.3 ‰) are all consistent 

with an atmospheric origin. While the bulk δ 15 N (-22.2 ‰) and site preference (SP; -3.6 ‰) values for 

N 2 O are consistent with a microbial origin, the δ 18 O value (3.0 ‰) is markedly depleted in 18 O relative 

to the vast majority of published values. The soils surrounding Don Juan Pond which is in a 

neighboring valley have been shown to produce N 2 O with variable δ 15 N, δ 18 O and SP values of -45.4 to 

-34.5 ‰, 50.5 to 76.7 ‰, and -45.2 to 4.1 ‰, respectively, that may reflect inorganic production by 

chemodenitrification (Samarkin et al., 2010). Nonetheless, the δ 18 O values of N 2 O in Lake Vida are 

markedly distinct from those observed in Don Juan Pond soils suggesting unique origins. Lake Vida 

brine was also characterized by an exceptionally high concentration of H 2 of 10.5 mM with a δ 2 H value 

of -704 ‰. This isotope value is consistent with production of H 2 by bacterial hydrogenase but also 

similar to values for H 2 generated by serpentinization or radiolysis. 

To understand pathways of nitrogen cycling in Lake Vida samples of brine were incubated in 

the presence of 15 N enriched ammonium, nitrite or N 2 O at a range of temperatures from -13 to +4 o C 

for up to 40 days. We found no evidence of nitrification, dissimilatory reduction of nitrate to 

ammonium or anaerobic ammonium oxidation. In the presence of 15 N enriched nitrite both N 2 and N 2 O 

exhibited initial 15 N enrichments but subsequently isotope values declined. These results are consistent 

with an initial reduction of nitrite followed by the generation of both N 2 and N 2 O from an unlabelled 

source; presumably nitrate. These results are consistent with an initial burst of N 2 and N 2 O production 

by chemodenitrification of nitrite followed by microbial production from nitrate. In support of this 

interpretation a total of 44 species of microbes have been isolated from Lake Vida brine and 9 species 

have been shown to be capable of denitrification. We postulate that H 2 production within Lake Vida 

provides energy sources to sustain the microbial assemblage over long periods of isolation from 

external inputs. This system is a relevant analog for studies of life in isolated subsurface ecosystems on 

Earth and on icy worlds in the solar system and beyond. As our understanding of the Lake Vida brine 

cryoecosystem improves we will develop a better understanding of the possibilities for extraterrestrial 

life in encapsulated, icy ecosystems elsewhere. 

Page 69


ISI 2012: 18- 22 June 2012 



THE DEVELOPMENT OF INTERNATIONAL STANDARDS AND COMMON CALIBRATION 

PROTOCOLS FOR NITROUS OXIDE ISOTOPOMERS 

Nathaniel E. Ostrom 1 

1 Department of Zoology, Michigan State University, East Lansing MI 48824-1115, USA, 

 

The two stable isotopes of N and three stable isotopes of O in N 2 O can combine to 

produce 12 possible isotopomers. Of these, 8 isotopomers have m/z values of 44, 45, or 

46 and can, therefore, be detected within a triple collector mass spectrometer. Site 

preference (the difference between in δ 15 N between the central, a, and outer, b, N atoms in 

N 2 O) is based on determination of δ 45/44 , δ 46/44 but also δ 31/30 and three additional 

isotopomers contribute to masses 30 and 31. Consequently, there is the need for mass 

overlap corrections and these are based on assumptions of mass dependence between 17 O 

and 18 O. Further, there is a need in the mass spectrometer to correct for “rearrangement” 

or “scrambling” in which a portion of N atoms in the a position exchange with those in the 

b position during analysis. Rearrangement factors need to be determined for each 

instrument and when instrument conditions change (i.e. source cleaning) that are based 

upon analysis of mixtures of natural abundance and standards enriched in the a or b 

positions. Thus accurate determination of isotopomer abundances in N 2 O is dependent 

upon (1) evaluation of the instrument rearrangement factor, (2) mass overlap corrections 

and (3) comparison of samples to internationally recognized standards. At present, there 

are no internationally recognized standards for N 2 O isotopomers available and standards 

have generously been provided by the laboratory of Naohiro Yoshida at the Tokyo 

Institute of Technology. In this talk I will review the current status of mass overlap 

corrections to be followed by open discussion with the goal of working toward (1) the 

development of several internationally recognized N 2 O standards and (2) the formal 

development of protocols and spreadsheets to assure common procedures for (a) 

determination of rearrangement factors and (b) mass overlap corrections. 

Page 70


ISI 2012: 18- 22 June 2012 



EXPERIMENTAL DATA ON VARIATIONS IN TRIPLE OXYGEN ISOTOPE EQUILIBRIUM 

FRACTIONATION EXPONENTS 

Andreas Pack * , Nina Albrecht, Magdalena E.G. Hofmann, Balázs Horváth, Alexander Gehler. 

Georg-August Universität, Geowissenschaftliches Zentrum, Abteilung Isotopengeologie, 

Goldschmidtstrasse 1, 37077 Göttingen, Germany ( * apack@uni-goettingen.de) 

Introduction: High-precision analyses of triple isotope ratios of coexisting phases (minerals, fluids, 

gases) allow the identification of the isotope fractionation effect [1]. Not considering true massindependent 

effects, only a few studies, made use of triple isotope relations [e.g., 2, 3, 4]. 

Understanding complex triple isotope fractionation networks [5-7] requires knowledge of θ for each 

fractionation process. We present the first experimental triple oxygen isotope equilibrium fractionation 

exponents θ including water, solids and gaseous CO 2 . 

Technique: Isotope analyses of oxides, silicates and phosphates are conducted by means of IR-laser 

fluorination in combination with GC-CF-irmMS (Thermo MAT 253). The precision in Δ 17 O varies 

between ±0.02 and ± 0.04 ‰ for a single analysis [8]. We use NBS-28 quartz (Δ 17 O TFL ≡ 0) and a 

rocks- and minerals-defined reference line (TFL) with a slope of λ TFL = 0.5251 and zero intercept when 

reporting Δ 17 O. For CO 2 we apply a novel technique that includes equilibration with solid CeO 2 and 

subsequent analysis of CeO 2 by fluorination [8, 9] with an accuracy and precision of ±0.03 ‰. For 

water, we have chosen literature data [e.g., 3, 4, 10] or had the water analyzed in the laboratory of 

A. Landais (Paris). 

Results: We have experimentally determined the triple isotope fractionation factor 

θ = ln(α 2/1 ) / ln(α 3/1 ) for oxygen for: (i) low-T oxygen isotope equilibrium fractionation between apatite 

and water with θ apatite-water = 0.526 ± 0.004 (2σ) [6], (ii) low-T oxygen isotope equilibrium fractionation 

between CO 2 and water with θ CO2-water = 0.522 ± 0.002 (2σ, independent of T, 4 ≤ T ≤ 37 °C [8]), (iii) 

high-T (granulite facies) oxygen isotope equilibration between quartz, fayalite and magnetite with θ qzfa-mt 

= 0.532, (iv) low-T oxygen isotope equilibration between silica and water with θ silica-water = 0.518 – 

0.521. 

Discussion: We show that θ varies for different equilibria and those variations in θ are not solely due 

to kinetic isotope effects. For three low-T processes (apatite-water, CO 2 -water, silica-water), θ is 

considerably lower than the high-T approximation of 0.5294 [1]. The only high-T system studied was a 

granulite facies rock with qz-fa-mt falling on a common line with slope of 0.532. This is, within 

uncertainty, identical to the high-T approximation of 0.5294. For the rocks- and minerals-defined TFL, 

slopes of 0.524 ≤ λ TFL ≤ 0.526 were reported [11-14]. Our data show that variations in λ TFL can solely 

explained by variations in θ. The understanding of triple isotope fractionation processes requires 

knowledge of θ’s not only for kinetic, but also for each equilibrium fractionation process involved. 

[1] Young, E.D., A. Galy, and H. Nagahara (2002) Geochimica et Cosmochimica Acta, 66: p. 1095-1104. 

[2] Galy, A., et al. (2000) Science, 290: p. 1751-1753. 

[3] Landais, A., et al. (2006) Geochimica et Cosmochimica Acta, 70: p. 4105-4115. 

[4] Landais, A., E. Barkan, and B. Luz (2008) Geophysical Research Letters, 35: p. L02709. 

[5] Hoag, K.J., et al. (2005) Geophysical Research Letters, 32: p. L02802:1-5. 

[6] Pack, A., A. Gehler, and A. Süssenberger (2012) Geochimica et Cosmochimica Acta, submitted. 

[7] Horvath, B., M.E.G. Hofmann, and A. Pack (2012) Geochimica et Cosmochimca Acta, submitted. 

[8] Hofmann, M., B. Horváth, and A. Pack (2011) Earth and Planetary Science Letters, 319-320: p. 159-164. 

[9] Hofmann, M.E.G. and A. Pack (2010) Analytical Chemistry, 82: p. 4357-4361. 

[10] Barkan, E. and B. Luz (2011) Rapid Communications in Mass Spectrometry, 25: p. 2367-2369. 

[11] Rumble, D., et al. (2007) Geochimica et Cosmochimica Acta, 71: p. 3592-3600. 

[12] Pack, A., C. Toulouse, and R. Przybilla (2007) Rapid Communications in Mass Spectrometry, 21: p. 3721-3728. 

[13] Miller, M.F. (2002) Geochimica et Cosmochimica Acta, 66: p. 1881-2055. 

[14] Ahn, I., et al. (2012) Geosciences Journal, 16: p. 7-16. 

Page 71


ISI 2012: 18- 22 June 2012 



EXPLORING THE USABILITY OF Δ 17 O OF BIOAPATITE AS PROXY FOR PAST 

ATMOSPHERIC CO 2 CONCENTRATIONS. 

Andreas Pack*, Alexander Gehler. Georg-August-Universität, Geowissenschaftliches 

Zentrum, Abteilung Isotopengeologie, Goldschmidtstraße 1, 37077 Göttingen, Germany 

(*apack@uni-goettingen.de) 

Introduction: Oxygen in mammalian bioapatite has a variety of sources and sinks. One 

source is inhaled air O 2 . Tropospheric O 2 has an isotope anomaly that varies in magnitude 

with the atmospheric CO 2 concentration. We attempted to (i) identify anomalous oxygen 

in bioapatite of modern mammals, (ii) to model the relation between body mass and Δ 17 O 

of bioapatite and (iii) to explore whether Δ 17 O of mammalian bioapatite is a suitable proxy 

for paleo-CO 2 studies. 

Technique: Isotope analyses were conducted by means of IR-laser fluorination in 

combination with GC-CF-irmMS (Thermo MAT 253). The precision in Δ 17 O varies 

between ±0.02 and ± 0.04 ‰ for a single analysis. We use NBS-28 quartz (Δ 17 O TFL ≡ 0) 

and a rocks- and minerals-defined reference line (TFL) with a slope of λ TFL = 0.5251 and 

zero intercept when reporting Δ 17 O. 

Results: Bioapatite of modern terrestrial mammals records the negative Δ 17 O of 

tropospheric O 2 . The magnitude of the anomaly recorded in the bioapatite increases with 

decreasing body mass. A decreasing Δ 17 O with decreasing body mass is also indicated by 

our mass balance model. Tooth enamel from a set of Cenozoic rodents has been analyzed 

for testing Δ 17 O as paleo-CO 2 barometer. All Cenozoic samples have a negative Δ 17 O. 

Discussion: The decreasing Δ 17 O of bioapatite with body mass is explained by the higher 

specific metabolic rates of small mammals compared to large mammals. The observed 

Δ 17 O-body mass-relation is well explained by mass balance modeling. It is recognized that 

the knowledge of the triple oxygen isotope fractionation exponent θ of each fractionation 

process is necessary for the interpretation of the data. We use the relation between Δ 17 O of 

air O 2 and CO 2 concentration to reconstruct paleo-CO 2 levels. Our data (though with large 

uncertainty) suggest that Δ 17 O of apatite of small terrestrial mammals can, indeed, be used 

as paleo-CO 2 barometer. 

Page 72


ISI 2012: 18- 22 June 2012 



THE STABLE ISOTOPIC COMPOSITION OF CARBON MONOXIDE FROM GREENLAND FIRN 

SAMPLES COLLECTED AT NEEM 

S. L. Pathirana and T. Röckmann. Institute for Marine and Atmospheric Research Utrecht (IMAU), 

Utrecht, Netherlands 

CO plays an important role in tropospheric chemistry. Precise measurement of its isotopic 

composition from the past is useful in constraining individual source and sink processes and thus 

its global cycle. High volume air samples from the NEEM 2009 S2 borehole were measured for 

mixing ratio, δ 13 C and δ 18 O of CO on a continuous-flow isotope ratio mass spectrometric (CF- 

IRMS) system. This system extracts the CO from the air sample (100mL-200mL or air required), 

converts the CO to CO 2 using Schütze reagent and transfers the CO 2 (derived from CO) via an 

open-split to the IRMS for isotope analysis. A single, automated, measurement is performed in 15 

minutes, so multiple measurements can be combined to improve precision. Each firn air sample 

was measured 10 times. The figure below shows CO mixing ratios and isotopic composition 

(δ 13 C V-PDB and δ 18 O V-SMOW ) as a function of depth. The data point at 71.9m (red) is questionable 

due to on-site sampling problems. The top 30 m of the firn show a signal from the seasonal cycle 

(Wang et al., 2011), in the bottom firn, CO mixing ratios show a maximum around 70 m, that 

seems to coincide with a slight δ 18 O maximum. The δ 13 C maximum appears to be higher up in the 

firn (~60 m) followed by a gradual decrease of ~1‰ to the 40 m level. 

Page 73


ISI 2012: 18- 22 June 2012 



OXYGEN ISOTOPE COMPOSITION OF MELTWATER FROM A NEOPROTEROZOIC GLACIATION 

IN SOUTHERN CHINA. 

Peng, Yongbo 1 , Bao, Huiming 1,2 , Zhou, Chuanming 3 , Yuan, Xunlai 3 , and Luo, Taiyi 2 

1. Department of Geology and Geophysics, Louisiana State University, Baton Rouge, LA 70803, 

USA , Email: pengyongbo@hotmail.com, 2. State Key Laboratory of Ore Deposit Geochemistry, 

Institute of Geochemistry, Chinese Academy of Sciences, Guiyang 550002, China, 3. Nanjing 

Institute of Geology and Palaeontology, Chinese Academy of Sciences, Nanjing 210008, China 

Water cycle is an integral part of Earth surface dynamics and the oxygen isotope 

composition of water holds information on Earth’s local and global climate and its driving forces. 

Water isotope signals of the recent geological past can be directly obtained from archives such as 

ice core, pore fluid, or groundwater. For the more distant past, mineral proxies have to be used. 

Multiple episodes of global glaciation may have occurred in the Neoproterozoic Era, an important 

period in Earth system evolution. There are few indications of the oxygen isotope composition of 

glacial meltwater of that time, and even the very few were derived from carbonate minerals which 

are prone to late burial and metamorphic alterations and therefore are subject to alternative 

explanations. Here we present a case in which the δ 18 O of meltwater from a Neoproterozoic 

glaciation is retrieved from sulfate associated with malachite (Cu 2 CO 3 (OH) 2 ) and barite (BaSO 4 ), 

which are the products of oxidative weathering of chalcocite (Cu 2 S) clasts in a glacial diamictite in 

Kaiyang, Guizhou, southern China. The δ 18 O of sulfate reaches as low as –20.3‰, the lowest ever 

reported for sulfate oxygen in literature. These data suggest that the water involving the oxidative 

weathering of chalcocite clasts has a δ 18 O value of –34 ±10‰, similar to that of polar glaciers 

today, whereas the Kaiyang diamictite was probably deposited at 635 million years ago when 

South China was at an equatorial paleolatitude. This study highlights a new utility of continental 

glacial deposits in recording information on past glaciation. 

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RADIOACTIVE 35-SULFUR: A UNIQUE TRACER TO QUANTIFY ATMOSPHERIC AIR MASS 

TRANSPORT AND CLOCK THE SULFUR CYCLE 

Antra Priyadarshi and Mark H Thiemens, 9500 Gilman Drive, University of California San Diego, 

La Jolla, 92093, California, USA 

The cosmogenic radionuclide 35 S (1) (half life ~87 d) exists in both 35 SO 2 gas and 35 2- 

SO 4 aerosol 

phases in the atmosphere. It fulfills a unique niche in that it has an ideal half-life for use as a tracer 

of atmospheric processes, possesses a gas phase precursor and undergoes gas to particle 

conversion, providing a chronometer that complements other measurements of radiogenic isotopes 

of different half-lives. All other radiogenic isotopes do not faithfully track air mass movements, 

have improper lifetimes, and do not simultaneously exist in gas, particle, liquid phases, facilitating 

direct determination of conversion times. We measured 35 S in aerosol samples collected at coastal 

and inland site in Antarctica (2) to understand stratospheric-tropospheric air mass transport 

dynamics and the atmospheric oxidation capacity on a short time scale (days to months). A year 

long measurement of 35 S in both 35 SO 2 (gas) and 35 SO 2- 4 aerosols collected during 2009-2010 at La 

Jolla, California shows that 35 SO 2 and 35 2- 

SO 4 activities were observed to be higher during 

stratospheric-tropospheric mixing and pressure-driven Santa Ana wind events that lead to high 

altitude air mass mixing into the marine boundary layer (3). We have also studied the trans-Pacific 

transport of 35 S produced within the nuclear reactor core during the Japanese Fukushima disaster 

(4,5). Based on these measurements, we were the first to recognize the nuclear core meltdown at 

Fukushima and estimate the neutron leakage from the core element rubble. Our ongoing 

measurement in samples collected from Japan shows that Fukushima was active even after 7 

months of the disaster (6). The simultaneous gas and particle speciation and 87 days half-life 

render 35 S a unique tracer to clock transformation and transportation. 

References: 

1. Lal D & Peters B (1967) Cosmic ray produced radioactivity in the earth. Hand. Phys. 

46:551-612. 

2. Priyadarshi A, Dominguez G, Savarino J, & Thiemens M (2011) Cosmogenic 35 S: A 

unique tracer to Antarctic atmospheric chemistry and the polar vortex. Geophys. Res. Lett. 

38(13):L13808. 

3. Priyadarshi A, Hill-Falkenthal J, Coupal E, Dominguez G, & Thiemens MH (2012) 

Measurements of 35S in the marine boundary layer at La Jolla, California: A new technique for 

tracing air mass mixing during Santa Ana events. J. Geophys. Res. 117(D8):D08301. 

4. Priyadarshi A, Dominguez G, & Thiemens MH (2011) Evidence of neutron leakage at the 

Fukushima nuclear plant from measurements of radioactive 35 S in California. Proceedings of the 

National Academy of Sciences 108(35):14422-14425. 

5. Sebastian Danielache, et al. (2012) A Numerical simulation of global transport of 

atmospheric radioactive 35 S emitted fro the Fukushia nuclear power plant. submitted to special 

edition of GJ. 

6. Priyadarshi, et al. (2012) Detection of Radioactive 35 S at Fukushima. In Preparation. 

Page 75


ISI 2012: 18- 22 June 2012 



DETERMINATION ON THE ABSOLUTE Δ(‰) Scale OF SITE-SPECIFIC 13 C COMPOSITION BY 

NMR SPECTROMETRY: AN INTER-LABORATORY COMPARISON 

G.S. Remaud 1 , V. Silvestre 1 , S. Akoka 1 , R. Hattori 2 , A. Gilbert 2 , N. Yoshida 2 , H. Sommer 3 , W. 

Fieber 3 , A. Chaintreau 3 . 1 EBSI team, CEISAM Laboratory, University of Nantes–CNRS 

UMR6230, 44322 Nantes, France. E-mail: gerald.remaud@univ-nantes.fr, 2 Department of 

Environmental Chemistry and Engineering, Interdisciplinary Graduate School of Science and 

Engineering, Tokyo Institute of Technology, Japan, 3 Firmenich SA, Corporate R&D Division, 1 

Route des Jeunes, 1211 Geneva 8, Switzerland. 

The site-specific 13 C/ 12 C composition (δ 13 Ci) of a given molecule is now accessible by 13 C NMR 

spectrometry. Isotopic 13 C NMR not only has to be very precise (s.d. ~ 1‰), but, ideally, also 

should give comparable δ 13 Ci values whichever laboratory has carried out the analysis. The 

repeatability of the measurement is closely related to the 1 H-decoupling performance of each 

spectrometer [1]. This was assessed by using [ 13 C 2 ]ethanol as a model. In this molecular probe, the 

ratio between the signals of the CH 3 and CH 2 positions is perfectly known and can be used to 

assess performance parameters [2]. 

Once the repeatability has been established, the reproducibility of isotopic 13 C NMR may be 

assessed within the framework of a ring test. This consisted of: (i) one chemical species, vanillin, 

obtained from four different origins and therefore of different intramolecular 13 C profiles: exguaiacol, 

ex-lignin, ex-bean and a biotechnological source from ferulic acid biotransformation; (ii) 

7 spectrometers of differing configuration (hardware, probe, etc), with the common parameter that 

they were all working at a 13 C frequency of 125.8 MHz (magnetic field, 9.4 T). Three key points 

can be identified: 

- each spectrometer showed a very good repeatability, with the standard deviation of 

precision lower than 1‰ for all 8 δ 13 Ci of vanillin; 

- the mean value of the standard deviation was 1.5‰, considering all carbons of vanillin 

- discrimination between all four origins of vanillin was achieved with each spectrometer. 

These results are very encouraging, but a question remains: what is the true δ 13 Ci value? Is it the 

mean value of the ring test? Or, in other words: is it possible to measure isotope effects on the 

δ(‰) scale when using 13 C isotopic NMR? The answer may be found by comparing NMR with a 

standardized technique such as IRMS. The aim of the present work was to address this problem by 

(i) finding a molecule for which site-specific isotope ratios can be determined by both IRMS and 

NMR, and (ii) comparing the values obtained with sufficient precision by each technique. Ethanol 

is a molecule for which the intramolecular isotope distribution can easily be determined using both 

isotopic 13 C NMR and IRMS. A sample set of consisting of ethanol from 16 different origins, thus 

large enough to retrieve data that are statistically significant, has been analyzed. The conversion of 

ethanol to acetic acid is a prerequisite to its site-specific analysis using IRMS [3]. The precision of 

this reaction has been assessed in terms of isotopic fractionation and chemical yield. A very good 

fit is found between the two techniques: δ 13 C CH2OH (NMR) = 0.976(0.037) δ 13 C CH2OH (IRMS) - 

0.138(0.658) (R² = 0.996). A similar trend is found for the CH 3 of ethanol. 

[1] Tenailleau, E.; Remaud, G.; Akoka, S. Instrument. Sci. Technol. 2005, 33, 391-399. [2] Caytan, E.; 

Botosoa, E. P.; Silvestre, V.; Robins, R. J.; Akoka, S.; Remaud, G. Anal. Chem. 2007, 79, 8266-8269. 

[3] Yamada, K.; Tanaka, M.; Nikagawa, F.; Yoshida, N. Rapid Commun. Mass Spectrom. 2002, 16, 1059- 

1064. 

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A" thirty" year" composite" record" of" the" isotopic" composition" of" atmospheric" methane" from" 

North"America" 

! 

Andrew"Rice,"Doaa."G."Teama","Erica"Hanson,"and"Chris"Butenhoff" 

Portland!State!University,!Department!of!Physics! 

Portland,!Oregon.!97207! 

! 

Methane!(CH 4 )!is!one!of!the!most!important!greenhouse!gases!after!water!vapor!and!carbon! 

dioxide.!Its!atmospheric!concentration!increased!from!650!ppb!during!the!preindustrial!era!to! 

nearly! 1800! ppb! in! the! present! day! due! to! human! activities! such! as! rice! cultivation,! animal! 

husbandry,!biomass!burning,!and!fossil!fuel!production!and!use.!Since!the!1980s,!the!longNterm! 

growth! rate! of! atmospheric! CH 4 ! slowed! dramatically! consistent! with! a! leveling! off! of! CH 4 ! 

sources.!Shorter!term!variability!obscures!this!trend.!One!powerful!tool!to!constrain!changes!in! 

sources!and!sinks!is!the!use!of!stable!isotopes!of!atmospheric!CH 4 !because!of!the!distinct!values! 

of! carbon! isotope! (δ 13 C)! and! hydrogen! isotope! (δD)! ratios! in!CH 4 !sources! and! characteristic! 

isotopic!fractionation!effects!in!sinks.!Therefore,!measurements!can!improve!the!constraint!of! 

changes! to! the! CH 4! budget! from! microbial! sources! (e.g.,! wetlands,! ruminants,! and! rice! 

agriculture,!δ 13 C ~N60!‰,!δD ~N300‰),!fossil!sources!(e.g.!natural!gas!and!coal!mining,!δ 13 C ~N 

40‰,!δD ~N200‰),!and!biomass!burning!(δ 13 C ~N25‰,!δD ~N100‰).!In!this!work,!we!present! 

measurements!of δ 13 C!and!δD!of!atmospheric!CH 4 !from!a!unique!archive!of!more!than!200!air! 

samples! collected! at! Cape! Meares,! Oregon! (45.5 o N,! 124 o W)! from! 1978! to! 1998.! The! 

measurements!from!this!archive!indicate!enrichments!in!both!isotope!tracers!over!this!period! 

which!average!0.017!(±0.002)!‰yr N1 for!δ 13 C!and!0.68!(±0.04)!‰yr N1 !for!δD.!!Seasonal!cycles!in! 

δ 13 C!and!δD!are!also!evident!with!amplitudes!of!~!0.3!‰!and!~!4!‰,!respectively;!maximum! 

values!are!found!MayNJuly!and!minimum!values!SeptemberNDecember,!consistent!with!previous! 

results! from! the! midNlatitude! northern! hemisphere.! Combining! our! results! with! more! recent! 

timeseries! since! 1988! from! Olympic! Peninsula! (WA,! 48 o N),! Montana! de! Oro!(CA,!35 o N),! and! 

Niwot!Ridge!(CO,!40 o N)!provides!a!composite!record!of!the!isotopic!composition!of!CH 4 !from! 

North!America!that!spans!roughly!three!decades.!The!composite!δ 13 C!and!δD!timeseries!show! 

marked! differences! from! northern! hemisphere! and! global! records! of! historical! CH 4 ! 

concentration.!Initially!rising!slowly!during!the!1980s!into!the!midN1990s,!the!values!of!δ 13 C!and! 

δD!increase!more!substantially!in!the!lateN1990s!and!then!appear!to!level!off!in!the!2000s!and! 

decrease!in!the!second!half!of!the!decade.!We!present!these!results!and!interpret!the!long!term! 

trends!in!isotopic!CH 4 !using!a!simple!box!model!to!describe!changes!in!CH 4! sources!over!this! 

period.! 

! 

First"Author"Information" 

Andrew!L.!Rice!! 

Department!of!Physics! 

Portland!State!University! 

Portland,!Oregon!97207N0751! 

arice@pdx.edu! 

503N725N3095! 

Page 77


ISI 2012: 18- 22 June 2012 



A POSSIBLE INTERPRETATION OF THE NON-MASS DEPENDENT ISOTOPIC FRACTIONATION 

EFFECT IN OZONE. 

François Robert 1 and Peter Reinhardt 2 . 1 LMCM, UMR-CNRS 7202 — Muséum National 

d’Histoire Naturelle (robert@mnhn.fr). France. 2 Université Pierre et Marie Curie, 

(reinh@lct.jussieu.fr). France. 

The non-mass dependent isotopic fractionation effect observed during the production of 

ozone 1,2,3,4,5 is incompletely understood. On one hand it is theoretically established that the 

observed mass dependency between the isotopomers of ozone results from the lifetime ratios of 

their respective complexes 6,7,8,9,10 . On the other hand, a residual isotopic fractionation effect is not 

accounted for by these theoretical approaches. If a parameter h is propagated to all the isotopic 

fractionation factors between the different isotopomers of ozone, most observations are then 

reproduced numerically. The aim of the present study is to propose a possible interpretation for h. 

Ozone is formed via the stabilization of the activated complex O3*.Two types of reactions 

are considered in the formation of O3*: reactive (subscript R; isotope exchange) or non-reactive 

(subscript NR; no isotope exchange): 

18 O + 16 O 16 O → O3* → 18 O + 16 O 16 O (NR) (1) 

18 O + 16 O 16 O → O3* → 16 O + 18 O 16 O (R) (2) 

We designate by (i) P NR the probability to select NR reactions that will yield ozone among all the 

possible NR reactions; by (ii) x NR the fraction of NR reactions relative to all the reactions (x NR is a 

constant; x NR + x R =1); (iii) the product x NR . P NR stands for the probability to select NR reactions 

that will yield ozone among all the possible reactions (iv) and by < τ > the lifetime of O3* 

resulting from all the reactions averaged over the Boltzmann distribution. The partition ω of the 

two lifetimes < τ NR > and < τ R > that contribute to the average lifetime < τ > of O3* stabilized as 

O3 is: 

ω = < τ NR > . x NR . P NR + < τ R > . x R . P R (3) 

yielding the average lifetime < τ > = ω / (x NR . P NR + x R . P R ). (4) 

In a reaction involving indistinguishable isotopes such as: 

16 O + 16 O 16 O → O3* → 16 O + 16 O 16 O (I) (5) 

it is not possible to decide if a given reaction contributes to < τ NR > or < τ R > . Therefore we decide 

to use the unique probability P I for this single set of reactions (subscript I standing for 

Indistinguishable). This gives: 

ω I = < τ NR > . x NR . P I + < τ R > . x R . P I (6) 

yielding the average lifetime: < τ I > = < τ NR > . x NR + < τ R > . x R (7) 

The two different average lifetimes < τ > and < τ I > are not necessarily equal, and an isotope 

fractionation can be observed; i.e.: < τ > / < τ I > = η 

Numerical simulations employing classical trajectories in a given O+O 2 potential (courtesy R. 

Schinke 10 ) show that this simple model - leaving out all the details of ozone stabilization or 

formation of ozone isotopomers - leads indeed to isotope fractionations comparable to 

experimental results 3,5,11,12 , discriminating between the i O i O i O, i O i O j O and i O j O k O species of ozone 

(i, j, k standing for mass 16, 17 and 18, respectively). 

References (1) K. Mauersberger, Geophys. Res. Lett., 8, 935, (1981). (2) M.H. Thiemens, Annu. Rev. Earth. Planet. 

Sci., 34, 217, (2006). (3) J. Morton, B. Schueler, K. Mauersberger, Chem.Phys.Lett, 154, 143, (1989). (4) C. Janssen, C. 

Guenther, K. Mauersberger, D. Krankowsky, Phys. Chem. Chem. Phys., 3, 4718, (2001). (5) M.H. Thiemens,T. Jackson, 

Geophys. Res. Lett., 17, 717, (1990). (6) R. Schinke, P. Fleurat-Lessard, J. Chem. Phys, 122, 94317, (2005). (7) R. 

Schinke, S.Yu. Grebenshchikov, M.V. Ivanov, P. Fleurat-Lessart, Ann. Rev. Phys.Chem., 57, 625, (2006). (8) Y.Q. Gao, 

R.A. Marcus, Science, 293, 259, (2001). (9) Y.Q. Gao, W-C. Chen, R. A. Marcus, J. Chem. Phys., 117, 1536, (2002). 

(10) R. Schinke, P. Fleurat-Lessard, S.Yu. Grebenshchikov, Phys. Chem. Chem. Phys., 5, 1966, (2003). (11) D. 

Krankovsky K. Mauerberger, Science, 244, 1324, (1996). (12) C. Janssen, B. Tuzson, J. Phys. Chem.A, 114, 9709, 

(2010). 

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ISI 2012: 18- 22 June 2012 



THE PANORAMA (AKA “ISOTOPOLOGOSAURUS”): A NEW GAS SOURCE MASS SPECTROMETER 

FOR THE MEASUREMENT OF ISOTOPOLOGUES IN GEOCHEMISTRY 

D. Rumble 1 , P. Freedman 2 , E. D. Young 3 , E. Schauble 3 , and W. Guo 4, 1 Geophysical Laboratory, 

5251 Broad Branch Rd., NW, Washington, DC, 20015, USA, ; 2 Nu 

Instruments Ltd; 3 University of California, Los Angeles; 4 Woods Hole Oceanographic Institution. 

The Panorama is a gas-source, electron-impact, double-focusing mass spectrometer with 

sufficient mass resolving power and sensitivity to make it possible to analyze the clumped 

isotopologues of gas molecules present in volcanic eruptive plumes, planetary atmospheres, 

geothermal hot springs, hydrocarbon deposits, deep crustal reservoirs, and low-temperature gas 

hydrates. The instrument will be used to calibrate experimentally the temperature dependence and 

kinetic rate constants of reactions involving clumped isotopologue molecules as reactants and 

products and to apply these calibrations to the interpretation of the measured abundances of 

clumped isotopologues occurring naturally in the lithosphere, hydrosphere, and atmosphere. The 

immediate goal is to complete the construction of a fully functional high-resolution mass 

spectrometer in two years. The following, third year, will be used to measure high-resolution mass 

spectra of single- and double-substituted isotopologues of molecules of geochemical interest, 

develop analytical protocols, and calibrate the instrument. The long-term goal of our research is to 

apply the calibrated instrument to such problems, for example, as quantitatively distinguishing 

between methane derived by thermal degradation of relict organic matter, or produced by 

inorganic synthesis, or generated by methanotrophs. The instrument is designed to achieve (1) 

high mass resolution; (2) high sensitivity; (3) low abundance sensitivity (minimal peak tailing); 

and (4) adaptability to the measurement of the abundances of the widest possible variety of 

molecular isotopologues. The concepts of Prof. Hisashi Matsuda of Osaka University have been 

used in the design to improve the transmission and decrease the aberrations of the mass 

spectrometer by deploying electrostatic lenses along the ion flight path. The new instrument will 

be available for use by all qualified scientists. It will be commissioned and operated under the 

supervision of an Advisory Council of internationally known scientists. 

Figure 1: The Panorama mass spectrometer measures 5 by 4 meters in plan view. 

Page 79


ISI 2012: 18- 22 June 2012 



GLOBAL OBSERVATION OF STRATO-MESOSPHERIC 18 OOO USING SMILES 

Tomohiro Sato 1,2 , Yasuko Kasai 1,2 , Hideo Sagawa 2 and Naohiro Yoshida 1 . 1 Tokyo Institute of 

Technology, Japan . 2 National Institute of Information and 

Communications Technology, Japan 

Isotopic enrichments on ozone (O 3 ) of about 10-15% in the lower and middle stratosphere were 

observed by both mass spectroscopic and remote-sensing spectroscopic measurements. The 

enrichment on O 3 had been understood well by the O 3 formation theory (e.g., Hathorn and Marcus, 

1999). In the upper stratosphere, higher enrichments on O 3 of about 20-30% were observed and 

contribution of photo-dissociation was suggested (e.g., Brenninkmeijer et al., 2003). Asymmetric 

and symmetric O 3 isotopomers have different isotopic behaviors in the stratosphere (Johnson et al., 

2000). One of the strongest advantages for remote-sensing spectroscopic measurement is separate 

observation of asymmetric and symmetric compositions such as 18 OOO and O 18 OO. It was showed 

that enrichment on 18 OOO (δ 18 OOO) was increasing with altitude in the stratosphere by balloonbased 

solar remote-sensing FTIR absorption spectroscopy (Haverd et al., 2005). Although it was 

preliminary, Kasai et al (2006) reported δ 18 OOO rises to 30% at 50 km by satellite measurements 

using Odin/SMR. Our research interest is stratospheric vertical profile on δ 18 OOO and its behavior 

in the mesosphere where the photo-chemical reaction is dominant. Direct measurements of 

δ 18 OOO, its solar zenith angle dependence (diurnal variation) and its global distribution are helpful 

to understand the photo-chemistry for δ 18 OOO. 

We performed the observation of O 3 isotopomers in the stratosphere and mesosphere using the 

Superconducting Submillimeter-wave Limb-emission Sounder (SMILES) onboard the the 

Japanese Experiment Module (JEM) of the <strong>International</strong> Space Station (ISS) (Kikuchi et al., 2010). 

The SMILES observation had been made from 12 October 2009 to 21 April 2010. SMILES 

observed the Earth’s atmospheric limb-emission spectra of O 3 , 18 OOO, O 18 OO, 17 OOO and O 17 OO 

with a better S/N ratio using a new 4K-receiving system, which enables to observe δ 18 OOO within 

a precision of a few percent order in the mesosphere. Moreover, non sun-synchronous orbit of 

SMILES observation (from ISS) can provide a diurnal variation on δ 18 OOO. We used the SMILES 

Level-2 research (L2r) products version 2.1.5. We discuss the performance of the observations of 

δ 18 OOO using SMILES by quantitative error analysis. The total, random and systematic errors for 

δ 18 OOO with averaging 100 profiles are about 10%, 2% and 10%, respectively, at 50 km. 

Brenninkmeijer C. A. M. et al., "Isotope effects in the chemistry of atmospheric trace compounds", Chem. 

Rev., 103, 5125-5161 (2003). 

Hathorn B. C. and Marcus R. A., "An intermolecular theory of the mass-independent isotope effect for 

ozone. I.", J. Chem. Phys., 111(9) 4087-4100 (1999). 

Haverd V. et al., "Evidence for altitude-dependent photolysis-induced 18 O isotopic fractionation in 

stratospheric ozone", Geophys. Res. Lett., 32, L22808, doi:10.1029/2005GL024049 (2005). 

Johnson D. G. et al., "Isotopic composition of stratospheric ozone", J. Geophys. Res., 105(7), 9025-9031 

(2000). 

Kasai Y. et al., “Global observation of isotopically substituted molecules by Odin/SMR”, 3 rd <strong>International</strong> 

Limb Workshop, Montreal, Canada, April 25-25 (2006). 

Kikuchi K. et al., “Overview and early results of the Superconducting Submillimeter-Wave Limb-Emission 

Sounder (SMILES)”, J. Geophys. Res. Atmos., 115, D23306, doi:10.1029/2010JD014379 (2010). 

NOTE: JEM/SMILES mission is a joint project of Japan Aerospace Exploration Agency (JAXA) and 

National Institute of Information and Communications Technology (NICT). 

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Changes in the oxidation capacity of the atmosphere revealed by stable isotopes in nitrate 

trapped in the Vostok ice core 

Savarino J. 1 , Erbland J. 1 and Alexander B. 2 

1 Laboratoire de Glaciologie et Géophysique de lʼEnvironnement, CNRS/Université Joseph 

Fourier, Grenoble France 

2 Department of Atmospheric Chemistry, University of Washington, Seattle, USA 

Nitrate (NO 3 - ) concentration records in ice cores have long been suspected to harbor 

information about the oxidative capacity of ancient atmospheres since this ion stems from the 

atmospheric oxidation of nitrogen oxides (NO x = NO + NO 2 ). At sites with low snow 

accumulation rates such as Vostok or Dome C (East Antarctic plateau), nitrate deposition to 

the snow is however not irreversible. Strong photochemical and/or physical mass loss 

processes can occur at the surface, thus hampering the interpretation of nitrate concentration 

records in the deep ice cores retrieved at these sites. Recent studies have shown the 

potential for the oxygen and nitrogen isotopic composition of the “fossilized” nitrate in ice 

cores to be used as a “window” on the past environmental conditions. Indeed, in the 

conditions prevailing today, nitrogen isotopes reflect the recycling and post depositional 

effects, while the 17 O-excess is directly linked with the local and summertime oxidation state. 

We present the first comprehensive isotopic analysis of nitrate (δ 15 N, δ 18 O, Δ 17 O) in a deep 

ice core. Selected samples of nitrate from the Vostok ice core reveal δ 15 N, δ 18 O and Δ 17 O 

values spanning ranges of [89-316 ‰], [28-71 ‰] and [23-36 ‰] respectively over the last 

150 000 years. A quantitative interpretation of the nitrate isotopic record in the Vostok ice 

core has been obtained using a recently developed modeling tool constrained by a wide 

spectrum of present-day surface isotopic measurements now available in the atmospheric 

and snow nitrate. 

The high positive δ 15 N(NO 3 - ) values measured in the Vostok ice core reveal that nitrate 

recycling has always occurred at the surface of the Antarctic plateau over this 150 000 years 

period. A direct consequence of this observed sustained recycling is that the Δ 17 O values can 

be used to derive the past signatures of the local and summer cycling and oxidation of NO 2 , 

over the Antarctic plateau. It then clearly indicates that intrusions of stratospheric air masses 

to the troposphere may have been more frequent in glacial ages thus incorporating 

significant amounts of stratospheric ozone to the lower atmosphere. A 3D global chemistry 

model has been used to model the past atmospheric conditions. It shows a large increase in 

the tropospheric ozone concentration between the pre industrial period and the glacial age 

that strongly supports our isotopic conclusion. It further shows an increase in tropospheric 

ozone and by consequence in OH radical concentrations at lower latitudes. This pleads for 

the reevaluation of the chemical lifetime of species of climatic interest such as CH 4 or CO 

over glacial timescales.! 

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ACCURATE PHOTOLYTIC ISOTOPE EFFECTS FROM FIRST PRINCIPLES 

J. A. Schmidt¹, M. S. Johnson¹, S. Hattori² and R. Schinke³ 

¹ University of Copenhagen, Department of Chemistry, Copenhagen, Denmark 

(johanalbrechtschmidt@gmail.com), 

² Tokyo Institute of Technology, Department of Environmental Science and Technology, 

Yokohama, Japan 

³ Max-Planck-Institut für Dynamik und Selbstorganisation, Göttingen, Germany 

Photodissociation is a quantum mechanical process. All experimental observables (e.g. the 

absorption cross section, product state distributions, scattering angles and isotope effects) can in 

principle be predicted by solving the Schrödinger equation. With modern computational power 

this approach provides accuracy and insight not available from other approaches, as we have 

successfully demonstrated for systems including HCl and N 2O. (Schmidt et al. 2009; 2011) 

We have recently developed a new model for describing the photodissociation of carbonyl sulfide 

(OCS) in the atmospherically relevant region from 190 nm to 250 nm. Using this model we 

calculate the absorption cross section for different isotopologues of OCS and derive sulfur and 

carbon isotopic fractionation constants. Our results agree well with experiments (Hattori et al 

2011) and are used to predict isotopic fractionation in the stratosphere. 

The predicted stratospheric fractionation is used to construct a qualitative sulfur isotope budget 

which – in contrast to earlier estimates – show that OCS is an acceptable background source of 

stratospheric sulfate aerosols. 

Figure: Experimental and theoretical sulfur-34 fractionation constant and ³³E for OCS photolysis at 295 K. 

Schmidt, J. A., Johnson, M. S., and Schinke, R.: Isotope effects in N 2O photolysis from first 

principles, Atmos. Chem. Phys., 11, 8965–8975, 2011 

Schmidt, J. A., Johnson, M. S., Grage, M. M.-L., and Nyman, G.: On the origin of the 

asymmetric shape of the HCl photodissociation cross section, Chem. Phys. Lett., 480, 168, 2009. 

Hattori, S., Danielache, S. O., Johnson, M. S., Schmidt, J. A., Kjaergaard, H. G., Toyoda, S., 

Ueno, Y., Yoshida, N. Ultraviolet absorption cross sections of carbonyl sulfide isotopologues 

OC 32 S, OC 33 S, OC 34 S and O 13 CS: isotopic fractionation in photolysis and atmospheric 

implications, Atmos. Chem. Phys., 11, 10293-10303, 2011. 

Schmidt, J. A., Johnson, M. S., McBane, G. C., and Schinke, R.: Communication: Multi-state 

analysis of the OCS ultraviolet absorption including vibrational structure, J. Chem. Phys., 136, 

131101, 2012. 

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ISOTOPE EFFECTS IN N 2O PHOTOLYSIS FROM FIRST PRINCIPLES 

J. A. Schmidt¹, M. S. Johnson¹, and R. Schinke² 

¹ University of Copenhagen, Department of Chemistry, Copenhagen, Denmark 

(johanalbrechtschmidt@gmail.com), 

² Max-Planck-Institut für Dynamik und Selbstorganisation, Göttingen, Germany 

This work gives important insight into the fundamental mechanism of isotopic fractionation in 

N 2O photolysis. Accurate potential energy surfaces allow N 2O cross sections and isotopic fractionation 

spectra to be derived that are in agreement with available experimental data, extending 

knowledge to a much broader range of conditions. Absorption spectra of rare N and O isotopologues 

( 15 N 14 N 16 O, 14 N 15 N 16 O, 15 N 2 

16 

O, 14 N 2 

17 

O and 14 N 2 

18 

O) are compared to the most abundant 

isotopologue ( 14 N 14 N 16 O). The fractionation constants as a function of wavelength and temperature 

are in excellent agreement with experimental data. The study shows that excitations from the 

3rd excited bending state, (0,3,0), and the first combination band, (1,1,0), are important for 

explaining the isotope effect at wavelengths longer than 210 nm. Only a small amount of the 

mass independent oxygen isotope anomaly observed in atmospheric N 2O samples can be 

explained as arising from photolysis. 

Figure: The fractionation constants for 15 N 14 N 16 O (Panel A), 14 N 15 N 16 O (Panel B), 15 N 2 

16 

O (Panel C) and 

14 

N 2 

18 

O (Panel D) at different temperatures compared to experimental results. The legend applies to all 

panels, however the results of this study in Panel d were calculated at 300 K (black) and 220 K (red). 

Figure taken from Schmidt et al. (2011). 

Schmidt, J. A., Johnson, M. S., and Schinke, R.: Isotope effects in N 2O photolysis from first 

principles, Atmos. Chem. Phys., 11, 8965–8975, doi:10.5194/acp-11-8965-2011, 2011 

Page 83


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OXIDATION AND REDUCTION CAPABILITIES OF O 2─ ION-CONDUCTING SOLID ELECTROLYTE 

REACTOR FOR SAMPLING IN CF-IRMS 

V.S. Sevastyanov 1 , N.E. Babulevich 2 , E.M. Galimov 1 , 1 Vernadsky Institute of Geochemistry and 

Analytical Chemistry, Moscow, Russia, vsev@geokhi.ru , 2 NRC Kurchatov Institute, Moscow, 

Russia, nickson1972@mail.ru 

A high temperature electrochemical solid electrolyte reactor (SER) based on stabilized 

zirconium dioxide (0.9ZrO 2·0.1Y 2 O 3 ) has been designed for oxidation of organic gases and for 

reduction of water or several organic substances in the continuous-flow isotope-ratio mass 

spectrometry (CF-IRMS). The SER is made of tubular, thin-walled zirconia ceramics with inner 

diameter of 1 mm and of 10 cm total length. To produce electrodes, both inner and outer surfaces of 

this tube were coated by platinum paste and then annealed in air. The solid-electrolyte reactor was 

connected in three-electrode circuit supported by the Elins PS8 Potentiostat. The inner electrode of the 

reactor serves as the working electrode. Reference electrode is on the outer side. Depending of the 

value of the potential of the working electrode, the SER can work in oxidation or reduction mode. The 

working temperature is ~ 950 °C. 

A mixture of hydrocarbon gases, methane and n-Undecane isotope standards, ethanol, benzene, 

pyridine, benzyl alcohol was used for studying the SER oxidation capabilities in GC-C-IRMS method 

(GC-SER-IRMS). The δ 13 C results were compared with those obtained by GC-C-IRMS with a standard 

oxidation reactor (Thermo Fisher Scientific, Germany). The δ 13 C values of the standards determined by 

our method were close to the accepted ones. 

δD values were determined using two different on-line methods: solid electrolyte reactor-isotope ratio 

mass spectrometry (SER-IRMS) for water and gas chromatography-combustion-solid electrolyte 

reactor-isotope ratio mass spectrometry (GC-C-SER-IRMS) for hydrocarbon gases. Water samples 

were calibrated against <strong>International</strong> water standards: VSMOW, GISP, SLAP, OH-1, OH-2, OH-3, 

OH-4. The HGS3 (RM 8561) natural gas isotopic standard has been used in developing a method for 

determination of isotopic composition of hydrogen in hydrocarbon gases by CF-IRMS. The 

measurement time of water δD values is 150 s. The required volume of a water sample is 0.2 µL when 

injected in the 500:1 split mode. If an optimal electrical potential (–1200 mV) is applied to the SER 

working electrode, water completely decomposes, the δD values obtained using this method being the 

same as the δD values reported for this water standard. If the absolute value of the electrochemical 

potential decreases, the water sample does not completely decompose, what leads to incorrect δD 

values. The precision of δD measurements in water is better or equal to 2.2‰ and that in hydrocarbon 

gases is within 0.5-3.0‰. The GC-C-SER-IRMS method has been tested with HGS3 (RM 8561) 

natural gas. Among hydrocarbon gases, methane is the worst oxidizable gas. If complete oxidation of 

methane takes place, then all hydrocarbon gases are sure to be oxidized. The measured value δD = 

−177.2 ± 1.1‰ of HGS3 (RM 8561) corresponds to the standard value. For the hydrocarbon gas 

mixture, the following results were obtained: δD(CH 4 )= -195.6±1.2 ‰, δD(C 2 H 4 )=-104.2±1.1 ‰, 

δD(C 3 H 8 )=-110.2±2.7 ‰, δD(iso-C 4 H 10 )=-199.1±0.5 ‰, δD(n-C 4 H 10 )= -173.4±2.3 ‰. 

The developed solid electrolyte reactor can be used for reduction of both water and oxygen 

containing organic molecules. We have reduced ethanol molecules (С 2 Н 5 ОН) with further 

determination of hydrogen isotope composition. It was found that the reduction of ethanol molecules is 

accompanied by the synthesis of small quantities of simple hydrocarbon molecules. For example, 

methane molecules are synthesized. The δD values for ethanol obtained by the SER-IRMS and by the 

TC/EA-IRMS method are −257.5 ± 1.9‰ and −255.1 ± 1.9‰ respectively. 

Due to its greater versatility as to the sample type and the mode of analysis, the GC-C-SER- 

IRMS method has a wider range of applications compared to the GC-TC-IRMS. In addition, our device 

is cost-effective because consumables are not necessary and the ceramic tube is inexpensive. 

Page 84


ISI 2012: 18- 22 June 2012 



STABLE CARBON ISOTOPE RATIOS IN ATMOSPHERIC METHANOL 

Holger Spahn 1 , Christian Linke 1 , Marc Krebsbach 1 , Ralf Koppmann 1 , Marcel vom Scheidt 1 , 

1 University of Wuppertal, Physics Department, Atmospheric Physics, Wuppertal, Germany 

spahn@uni-wuppertal.de 

Methanol is the most abundant oxyganted VOC in the troposphere. Thus, methanol has a 

significant impact on tropospheric chemistry. It is a sink for hydroxyl radicals, but can also 

increase the concentration of oxidants in the atmosphere depending on the chemical situation. 

Despite its importance, sources, sinks and the atmospheric cycle of methanol are still not fully 

understood. Chemistry and transport models have to deal with large uncertainties in emission 

inventories and unresolved photochemical mechanisms. 

Measurements of stable carbon isotope ratios (δ 13 C) have been successfully applied to other trace 

gases and improved our insights in their atmospheric budgets. In the same way we will use 

measurements of the stable carbon isotope ratios of methanol to investigate its role in atmospheric 

chemistry and its atmospheric budget. Knowing the δ 13 C values of methanol allows to trace 

chemical pathways, determine the photochemical aging and help to understand the sources and 

sinks of methanol. The increasing number of laboratory investigations regarding the biogenic 

emissions of methanol will help to identify possible sources of methanol from measurements in 

ambient air. 

Here we present δ 13 C measurements of methanol from whole air samples obtained during airborne 

and ground based field campaigns in Spain and Germany. The samples have been collected with a 

custom made automated sampling unit aboard a Zeppelin NT over southern Germany and a CASA 

C-212-200 airplane over Spain. Included in this study are also whole air samples from the new 

sampling unit MIRAH (Measurements of Isotope Ratios in the Atmosphere on HALO), which was 

operated on the new German research aircraft during a technical mission in summer 2010 and 

during the ground based campaign PARADE (Particles And Radicals: Diel observations of the 

impact of urban and biogenic Emissions) at the Taunus observatory on the summit of Kleiner 

Feldberg, Germany, about 10 km north of Frankfurt in late summer 2011. 

In general, the stable isotope ratios suggest a mainly biogenic origin of methanol. On average, the 

isotope ratios were around - 45 ‰. In contrast to the wide range of δ 13 C values found in laboratory 

studies for different sources (- 80 ‰ to - 15 ‰), the isotope ratios measured in all field 

experiments varied significantly less. The largest variations were found during the airborne 

campaigns. During the aircraft campaign over Spain methanol isotope ratios ranged from - 50 ‰ 

to - 35 ‰ with no significant differences between urban and rural air masses. However, the 

variations decreased with increasing altitude in the planetary boundary layer. During the Zeppelin 

campaign methanol isotope ratios ranged from - 44 ‰ to - 22 ‰ and showed a pronounced 

bimodal distribution. This might be an indication that the observed methanol mixing ratios were 

either due to the contribution of completely different sources or to the mixing of different 

photochemically aged air masses. 

Page 85


ISI 2012: 18- 22 June 2012 



ISOTOPIC FRACTIONATION DURING PHOTODISSOCIATION OF SO. 

Tomoya Suzuki 1 , Sebastian O. Danielache 2 , Yuichiro Ueno 2 , Shinkoh Nanbu 1 . 1 Sophia University, 

Japan, 2 Tokyo Institute of Technology 

Sulfur monoxide (SO) is a system that it has been studied for many years. This diatomic 

molecule is suitable for theoretical calculations which have studied many of its properties and 

electronic structure. Experimental studies are however less abundant since SO is highly reactive 

and unstable under most experimental and atmospheric conditions. It has been estimated that the 

Archean atmosphere possesses an SO 2 mixing ratio in the order of 10 ppm, and the 

photodissociation of SO 2 is one of the main sources of the non-mass dependent effects recorded in 

the geological record [1]. If only this estimation is somewhat accurate then it can be confidently 

assumed that there is a stable SO pool in the atmosphere where is subject to isotopic effects from 

competing sink reactions. 

In this study, we report ultraviolet absorption cross sections and isotopic fractionation 

constant for 32,33,34,36 SO isotopologues calculated at different temperatures. The obtained spectra 

(Fig. 1) reproduce the complex vibrational structure and features experimentally observed [2]. We 

discuss obtained ε 33 S, ε 34 S, ε 36 S, E 33 S and E 36 S spectra and their potential implications for the 

terrestrial Archean and other planets atmospheres. 

Fig. 1 Calculated absorption cross sections for 32,33,34,36 SO 

[1] Ueno, Y, Johnson, M. S., Danielache, S. O., Eskebjerg, C., Pandey, A., Yoshida N. Geological 

sulfur isotopes indicate elevated OCS in the Archean atmosphere, solving faint young sun paradox. 

Pro. Nac. Ac. Sci, 10.1073, 2009. 

[2] Phillips L. F., J. Phys. Chem., 85, 3994-4000, 1981. 

Page 86


ISI 2012: 18- 22 June 2012 



ISOTOPIC FRACTIONATION DURING METHANE UPTAKE IN TEMPERATE 

FOREST SOIL 

N. SUZUKI 1 , K. Koba, 2, 3 M Itoh, 4 K. Osaka, 5 N. Ohte, 6 Y. Tobari, 2 K Yamada 1 and N. Yoshida 1 

1 Department of environmental chemistry, Tokyo Institute of Technology (suzuki.n.ae@m.titech. 

ac.jp), 2 Department of environmental science and technology, Tokyo Institute of Technology, 3 

Faculty of Agriculture, Tokyo University of Agriculture and Technology, 4 Center for Southeast 

Asian Studies, Kyoto University, 5 Department of ecosystem Studies, University of Shiga 

Prefecture, 6 Faculty of Agriculture, University of Tokyo 

Soil is quite important in the global methane (CH 4 ) budget because it can act as both a sink and 

a source [2] . The importance of soil as a methane sink may change in the future with changes in 

environmental factors such as precipitation and temperature [3] . In such calculations, the kinetic 

isotope fractionation factor (KIE) affects the estimation considerably. However, few studies 

report fractionation factors for CH 4 uptake in soils, possibly because of measurement difficulties. 

The KIE during soil CH 4 uptake is usually calculated by soil incubation or by using a static 

chamber employed in the field. Soil incubation is suitable for controlling environmental factors [1] , 

but environmental conditions are different in soil incubation from the conditions in natural 

environmental settings. On the other hand, static chamber method can provide the KIE directly in 

the natural environment, although the required sample volume has prevented frequent sampling 

from a static chamber [6] . Moreover, static chambers installed for short periods during gas 

sampling should be prone to bias caused by variations in environmental factors that impact CH 4 

uptake, such as weather. Thus, Reeburgh et al. [5] and Maxfield et al. [4] used the soil gas profile 

method rather than the flux chamber method, because gas profiles within the soil integrate the 

longer-term steady-state effects of soil CH 4 uptake in a better way. Although the gas profile 

method is promising for KIE calculation, it is not suitable for estimating the KIE in forest soil, in 

which CH 4 consumption and production can occur simultaneously [7] . However, information on 

such heterogeneity in oxic/anoxic environments in the soil is difficult to obtain and is essential 

for better understanding of biogeochemical processes in soils. 

The purpose of this study is to investigate the profile of the concentration and δ 13 C of CH 4 in a 

temperate forest soils and to estimate KIEs during soil CH 4 uptake by both the static chamber 

method and other soil gas profile methods. In this study, we calculated the apparent carbon 

isotopic fractionation factor during soil CH 4 uptake by the flux ratio, top-to-bottom, Rayleigh, 

and static chamber methods. Field sampling was conducted in a temperate forested soil in Kiryu 

Experimental Watershed, which is located at 34º 58’ N, 136° 00’ E. Because redox conditions in 

the soil strongly influence CH 4 oxidation rates, several sampling points in the watershed with 

different groundwater levels were selected. Our results, which came out of the first experiment in 

a temperate forest soil, indicated that all the methods can provide similar results, which were also 

similar to the reported value used for global CH 4 budget studies. However, the concentrations, 

δ 13 C values and apparent KIEs in oxidation of CH 4 in the soil gas and the headspace of the static 

chambers fluctuated considerably, suggesting simultaneous CH 4 production and consumption in 

forest soil. 


[1] D.D. Coleman et al. Geochim. et Cosmochim. Acta, 45, 1033-1037, (1981). 

[2] IPCC Fourth Assessment Report: Climate Chance 2007, (2007) 

[3] M. Itoh et al. Soil Biol. Biochem., 41, 388-395, (2009). 

[4] P.J. Maxfield et al. Sci. Tech., 42, 7824-7830, (2008). 

[5] W.S. Reeburgh et al. Geochim. et Cosmochim. Acta, 61, 4761-4767, (1997). 

[6] A.K. Snover and P.D. Quay. Global Biogeochem. Cycles, 14, 25-39, (2000). 

[7] J.C. von Fischer and L.O. Hedin. Global Biogeochem. Cycles, 16, 10.1029/2001GB001448, 

(2002). 

Page 87


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KINETIC ISOTOPE FRACTIONATION EFFECT OBSERVED IN OXYGEN TRIPLE ISOTOPE RATIOS 

IN TERRESTRIAL SILICATE MINERALS 

Ryoji Tanaka 1 and Eizo Nakamura 1 . 1 The Pheasant Memorial Laboratory for Geochemistry and 

Cosmochemistry, Institute for Study of the Earth’s Interior, Misasa, 682-0193, Japan. 

 

Oxygen is a major element common to the geosphere, hydrosphere, atmosphere, and biosphere and 

its triple isotope systematics gives key information for understanding inter-sphere elemental and 

mass fractionation processes. In this study, oxygen triple isotope ratios of terrestrial water and 

silicate/oxide minerals and so-called terrestrial fractionation line were precisely analyzed using the 

same purification line and mass spectrometer but with separate fluorination systems designed for 

the analysis of water and solid materials, respectively. The water fluorination system uses 

electrically-heated Ni-metal tubes into which water and BrF 5 are loaded for the quantitative 

extraction of oxygen. Fluorination of silicate/oxide minerals was accomplished by heating samples 

with an infrared laser (CO 2 laser) in an atmosphere of BrF 5 . Using the water fluorination system, 

δ 17 O and δ 18 O of international reference water samples (GISP, SLAP) and in-house water sample 

were determined relative to those of VSMOW. The reliability of δ 18 O of these water samples were 

double-checked by thermal conversion elemental analyzer coupled to a continuous flow isotope 

ratio mass spectrometer. We also evaluated the appropriate fluorination method for silicate/oxide 

minerals and revaluated VSMOW-normalized δ 18 O of internationally accepted silicate reference 

material, NBS-28 quartz, UWG-2 garnet, and San Carlos olivine. Using the obtained data, oxygen 

triple isotope ratios of terrestrial water and minerals form a mass-dependent fractionation line, 

defined as [ln(δ 17 O/1000+1) = λln(δ 18 O/1000+1) + Δ/1000], where λ and Δ are slope and intercept 

(Miller, 2002). We measure the different mass fractionation line between silicate/oxide and 

meteoric water. The mass fractionation line for meteoric water has λ = 0.5281 ± 0.0004 and Δ = 

0.011 ± 0.015. Igneous and metamorphic minerals give values of λ = 0.5270 ± 0.0005 and Δ = - 

0.070 ± 0.005 at the 95 % confidence limit. Lower λ and Δ values for silicate/oxide minerals 

should be influenced by kinetic fractionation effect by variable geological processes. The lower λ 

and Δ values for silicate/oxide minerals compared to those of meteoric water should be caused by 

the influence of kinetic fractionation effects occurring during water-rock interactions throughout 

Earth’s history. We propose to use “terrestrial silicate fractionation line (TSFL)” when we analyze 

δ 17 O of terrestrial and extraterrestrial solid materials to distinguish from global meteoric water line 

(GMWL). Also it is necessary to specify if the determined δ 17 O is expressed as the difference from 

TSFL or GMWL. 


Miller, M.F. (2002) Isotopic fractionation and the quantification of 17 O anomalies in the oxygen 

three-isotope system: an appraisal and geochemical significance. Geochim. Cosmochim. Acta 66, 

1881-1889. 

Page 88


ISI 2012: 18- 22 June 2012 



DECADAL TIME SERIES OF TROPOSPHERIC N 2 O ISOTOPOMER RATIOS IN THE NORTHERN 

HEMISPHERE OBTAINED BY THE LONG-TERM OBSERVATION AT HATERUMA ISLAND, JAPAN 

Sake Toyoda 1 , Natsuko Kuroki 2 , Naohiro Yoshida 1,2 , Kentaro Ishijima 3 , Yasunori Tohjima 4 , and 

Toshinobu Machida 4 , 

1 Department of Environmental Science and Technology, Tokyo Institute of Technology, 4259 

Nagatsuta, Midori-ku, Yokohama 226-8502, Japan, toyoda.s.aa@m.titech.ac.jp, 2 Department of 

Environmental Chemistry and Engineering, Tokyo Institute of Technology, 4259 Nagatsuta, 

Midori-ku, Yokohama 226-8502, Japan. 3 Research Institute for Global Change, Japan Agency for 

Marine-Earth Science and Technology, 3173-25 Showamachi, Kanazawa-ku, Yokohama 236-0001, 

Japan. 4 National Institute for Environmental Studies, 16-2 Onogawa, Tsukuba, 305-8506, Japan 

Time series of mixing ratio and isotopomer ratios of atmospheric nitrous oxide (N 2 O) have 

been obtained at Hateruma Island (HAT), Japan during 1999–2010 by monthly air sampling. 

Results show that the bulk nitrogen isotope ratio δ 15 N bulk decreased at the rate of -0.023±0.006‰ 

yr -1 , although the N 2 O mixing ratio increased at the rate of about 0.7 ppbv yr -1 during the period. 

Isotopomer budget calculation with the δ 15 N bulk trend supports the earlier estimates showing that 

the isotopically light sources such as agriculture and industry contribute to the increase of 

atmospheric N 2 O. However, the rate of decrease of δ 15 N bulk is slightly smaller in magnitude than 

the rates obtained from firn air in polar regions and surface air in Antarctica in the previous 

century, which suggests greater contribution of 15 N-enriched N 2 O sources in recent years. In 

contrast, the oxygen isotope ratio (δ 18 O) and intramolecular 15 N site preference (SP, difference 

between isotopomer ratios with respect to central and terminal nitrogen atoms) of N 2 O showed no 

significant decreasing and increasing trend, respectively, although previous reports of studies in 

polar regions described such trends [Bernard et al., 2005; Ishijima et al., 2007; Röckmann et al., 

2003; Röckmann and Levin, 2005; Sowers et al., 2002]. Results demonstrate that no significant 

seasonal variation exists in isotopomer ratios of N 2 O in the northern mid-latitude troposphere in 

the past decade within the limits of our sampling frequency and analytical precision. 


Bernard, S., T. Röckmann, J. Kaiser, J.-M. Barnola, H. Fischer, T. Blunier, and J. Chappelaz 

(2006), Constraints on N 2 O budget changes since pre-industrial time from new firn air and 

ice core isotoper measurements, Atmos. Chem. Phys., 6, 493-503. 

Ishijima, K., S. Sugawara, K. Kawamura, G. Hashida, S. Morimoto, S. Murayama, S. Aoki, and T. 

Nakazawa (2007), Temporal variations of the atmospheric nitrous oxide concentration and 

its d 15 N and d 18 O for the latter half of the 20th century reconstructed from firn air analyses, 

J. Geophys. Res., 112, D03305, doi:10.1029/2006/JD007208. 

Röckmann, T., J. Kaiser, and C. A. M. Brenninkmeijer (2003), The isotopic fingerprint of the preindustrial 

and the anthropogenic N 2 O source, Atmos. Chem. Phys., 3, 315-323. 

Röckmann, T., and I. Levin (2005), High-precision determination of the changing isotopic 

composition of atmospheric N 2 O from 1990 to 2002, J. Geophys. Res., 110, D21304, 

doi:doi:10.1029/2005JD006066. 

Sowers, T., A. Rodebaugh, N. Yoshida, and S. Toyoda (2002), Extending records of the isotopic 

composition of the atmospheric N 2 O back to 1800 A.D. from air trapped in snow at the 

South Pole and the Greenland Ice Sheet Project II ice core, Global Biogeochem. Cycles, 

16(4), 1129, doi:10.1029/2002GB001911. 

Page 89


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SPECTROSCOPIC MEASUREMENT OF 13 CH 3 D/ 12 CH 3 D AND 13 CH 3 D/ 12 CH 4 USING A MID- 

INFRARED DIFFERENCE-FREQUENCY-GENERATION SOURCE 

Kiyoshi Tsuji 1 , Hiroaki Teshima 2 , Hiroyuki Sasada 2 , Naohiro Yoshida 1 . 1 Interdisciplinary 

Graduate School of Science and Engineering, Tokyo Institute of Technology, 

ktsuji@depe.titech.ac.jp, 2 Department of Physics, Faculty of Science and Technology, Keio 

University. 

Clumped isotopes or multiply substituted isotopologues have attracted considerable attentions 

because of their unique behaviors in environments. 13 C 18 O 16 O(47-CO 2 ) was indeed measured using 

mass-spectrometry [1]. Since minor isotopes usually have natural abundance of less than 1%, 

abundance of clumped isotopes is less than 10 –4 . To measure the subtle amount, we developed a 

sensitive and widely tunable DFG (Difference Frequency Generation) spectrometer in the 3.4 µm 

wavelength region, and determined 12 CH 3 D/ 12 CH 4 ratio with a high precision of ~ 0.8‰ [2]. In this 

paper, we have measured clumped isotopes of 13 CH 3 D in natural methane. Most lines of 13 CH 3 D are 

overlapped with and hidden by those of abundant isotopologues (AI's). Therefore, the wide tunability 

of the spectrometer is required to access absorption line pairs of 13 CH 3 D and AI's suitable for isotope 

ratio measurements. We have cooled an absorption cell with dry ice to reduce the intensity and line 

width of the AI's and the overlap of 13 CH 3 D with the AI's. 

Table 1 lists absorption lines suitable for isotope ratio measurement of 13 CH 3 D and AI's. There are 

appropriate lines of AI's near the 13 CH 3 D lines, and each pair has similar line intensity and energy of 

the lower level of the transition. Isotope ratios of 13 CH 3 D/ 12 CH 3 D and 13 CH 3 D/ 12 CH 4 have been 

determined with a precision of ~20 ‰. We have discussed a deviation from the scrambled (random) 

value of 13 CH 3 D ratio and a comparison with the thermal equilibrium population of 13 CH 3 D predicted 

in [3]. 

We are grateful to Dr. Keita Yamada in Tokyo Institute of Technology for critical reading of the 

manuscript and valuable comments. 

Table 1. Spectroscopic data of absorption lines for isotope ratio measurements 

Assignment Wavenumber [cm −1 ] Line intensity @296K [cm −1 /(molecule· 

cm −2 )] 

12 CH 3 D 2ν R 5 Q (9, 0) 2952.59496 4.858 × 10 −25 

12 CH 4 v 2 +v 4 R(10) F 2 2952.879109 6.007 × 10 −23 

13 CH 3 D ν R 4 P (7, 0) 2952.92 a 

(2962.475484) 

1.1 × 10 −25 b 

(1.041 × 10 −23 ) 

13 CH 3 D ν P 4 P (6, 3) 2954.75 a 

(2964.503) 

2.7 × 10 −25 b 

(2.44 × 10 −23 ) c 

12 CH 4 ν 3 P (6) E 2954.98663 5.918 × 10 −23 

HITRAN 2008 

The values in parentheses are those for the identical vibration-rotation transition of 12 CH 3 D. 

a Wavenumbers measured in this work. 

b 

Intensity calculated by multiplying that of the corresponding line of 12 CH 3 D with [ 13 C/ 12 C]. 

c Sum of the A 1 and A 2 components. 

[1] J. M. Eiler, “Clumped-isotope” geochemistry―The study of naturally-occurring, multiply-substituted isotopologues”, 

Earth Planet. Sci. Lett., Vol. 262, 2007, pp. 309-327. [2] K. Tsuji, H. Teshima, H. Sasada and N. Yoshida, “An efficient 

and compact difference-frequency-generation spectrometer and its application to 12 CH 3 D/ 12 CH 4 isotope ratio 

measurements”, Sensors, Vol. 10, No. 7, 2010, pp. 6612-6622. [3] Q. Ma, S. Wu and Y. Tang, “Formation and 

abundance of doubly-substituted methane isotopologues ( 13 CH 3 D) in natural gas systems”, Geochim. Cosmochim. Acta, 

Vol. 72, No. 22, 2008, pp. 5446-5456. 

Page 90


ISI 2012: 18- 22 June 2012 



ISOTOPOMER ANALYSIS OF N 2 O PRODUCTION-CONSUMPTION MECHANISMS IN BIOLOGICAL 

WASTEWATER TREATMENT UNDER NITRIFYING AND DENITRIFYING CONDITIONS 

Azzaya Tumendelger 1 , Sakae Toyoda 2 , Naohiro Yoshida 1 . 1 Department of Environmental 

Chemistry and Engineering, Tokyo Institute of Technology, 4259 Nagatsuta, Midori-ku, 

Yokohama, 226-8502, Japan. tumendelger.a.ab@m.titech.ac.jp. 2 Departmentof Environmental 

Science and Technology, Tokyo Institute of Technology, 4259 Nagatsuta, Midori-ku, Yokohama, 

226-8502, Japan. 

Nitrous oxide (N 2 O) is an effective greenhouse gas that is important in climate change, and 

it is also a stratospheric ozone depleting substance. It can be produced in substantial amounts 

during biological nitrogen removal processes in wastewater treatment plant (WWTP) where 

inorganic and organic nitrogen compounds are converted to nitrate and dinitrogen by bacterial 

nitrification and denitrifcation. 

In this study, the mechanisms of N 2 O production-consumption were investigated using 

isotopomer analysis of N 2 O in a laboratory batch-scale system. Activated sludge was incubated 

under several conditions of nitrogen substrate, dissolved oxygen (DO), and carbon-nitrogen (C/N) 

ratio to simulate nitrification and denitrification. About 200 mL of water was sampled from 30-L 

incubation chamber for several times during the incubation, and concentration and isotopomer 

ratios of N 2 O and N-containing species were measured. In experiments simulating nitrification 

under DO concentration of 0.5 and 0.8mgL -1 , ammonium (NH 4 + ) consumption was accompanied 

by buildup of nitrite (NO 2 - ), and the dissolved N 2 O concentration gradually increased to 4850 and 

5650nmol kg -1 , respectively, during the four-hour incubation. The NO 2 - accumulation should have 

been caused by oxygen limitation which can also be enhanced N 2 O production. Based on 

measurement of isotopomer ratios of substrate and product (δ 15 N, δ 18 O of NO 3 - , NH 4 + and N 2 O) 

and site preference (SP), the N 2 O is mainly produced by nitrifier-denitrification of ammoniaoxidizing 

bacteria (AOB). In anaerobic experiments simulating denitrification, the N 2 O 

concentration reached its maximum (1250nmol kg -1 ) at 30min when C/N ratio of around 

6mgO/mgN. Isotopomer analysis (SP, δ 15 N bulk , δ 18 O) revealed that the N 2 O reduction to dinitrogen 

gas occurred during the incubation. 


1. IPCC, 2006. 

2. Tallec G. et al., 2006a. Nitrous oxide emissions from secondary activated sludge in nitrifying 

conditions of urban wastewater treatment plants: effect of oxygenation level. Water Research 

40 (15), 2972–2980. 

3. Toyoda S. and Yoshida N. 1999. Determination of nitrogen isotopomers of nitrous oxide on a 

modified isotope ratio mass spectrometer. Anal. Chem. 71, 4711–4718. 

4. Yoshida N. and Toyoda S. 2000. Constraining the atmospheric N 2 O budget from 

intramolecular site preference in N 2 O isotopomers. Nature 405, 330–334. 

5. Toyoda S. et al, 2011.Isotopomer analysis of Production and Consumption Mechanisms of 

N 2 O and CH 4 in an Advanced Wastewater Treatment System. Environ. Sci. Technol, 45, 917- 

922. 

6. Wunderlin P. et al., 2012. Mechanisms of N 2 O production in biological wastewater treatment 

under nitrifying and denitrifying conditions. Water Research, 46, 1027-1037 

Page 91


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SPECTROSCOPIC PREDICTION OF Δ 36 S ANOMALY BY SO 2 PHOTOLYSIS AND THE ARCHAEAN 

ATMOSPHERE 

Yuichiro Ueno 1 , Sebastian O. Danielache 1 , Matthew Johnson 2 

1 Tokyo Institute of Technology, Japan, ueno.y.ac@m.titech.ac.jp, 2 University of Copenhagen, 

Denmark 

The mass independent fractionation of sulfur isotopes (S-MIF) in geological samples may 

provide a record of the past atmospheric composition, however, the mechanism of photochemical 

S-MIF is still poorly understood [1]. A previous study of this hypothesis applied the ultraviolet 

absorption cross sections of 32 SO 2 , 33 SO 2 and 34 SO 2 [2] to a model of the Archean atmospheric 

chemistry [3]. We present newly measured ultraviolet absorption cross sections of SO 2 

isotopologues including 36 SO 2 , recorded from 190 to 220 nm at room temperature with a resolution 

of 4 cm -1 which have been employed in single box model study of the Archean atmosphere. In this 

new study the carbon and sulfur cycles were complemented by a rich and complex gas phase 

chemistry to examine the production and stability of organic sulfur compounds. 

While the calculated photochemical fractionation pattern assuming broadband solar UV flux 

reproduces our previous work [2], the effect of UV shielding by each atmospheric species 

including SO 2 itself differs from the previously estimated trend. Nonetheless, almost all of the 

simulations result in a Δ 36 S/Δ 33 S ratio of -0.9 ~ -1.1, generally reproducing the patterns observed in 

Archean sedimentary rocks. Thus, we conclude that photodissociation of SO 2 was a primary MIFyielding 

reaction in the Archean atmosphere. On the other hand, preservation of the MIF signal is 

not straightforward. The fate of MIF-bearing sulfur species may rely on the mechanism of 

production and consumption of organic sulfur compounds in the atmosphere. 

References 

[1] Lyons, J.R., Atmospherically-derived mass-independent sulfur isotope signatures, and 

incorporation into sediments, Chem. Geol., 267, 164-174, 2009. 

[2] Danielache, S., Eskebjerg, C., Johnson, M. S., Ueno Y., Yoshida N., High-precision 

spectroscopy of 32 S, 33 S, and 34 S sulfur dioxide: Ultraviolet absorption cross sections and isotope 

effects, J. Geophy. Res., 113, D17314, 2008. 

[3] Ueno, Y., Johnson, M. S., Danielache, S. O., Eskebjerg, C., Pandey, A., Yoshida N. Geological 

sulfur isotopes indicate elevated OCS in the Archean atmosphere, solving faint young sun paradox. 

Pro. Nac. Ac. Sci, 10.1073, 2009. 

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Spatial and temporal variability in the 17 O-excess (Δ 17 O) of surface ozone: Ambient 

measurements using the nitrite-coated filter method 

William C. Vicars 1 , S. K. Bhattacharya 1,2 , Joseph Erbland 1 , and Joël Savarino 1 

1 Laboratoire de Glaciologie et Géophysique de l’Environnement, Université Joseph Fourier- 

Grenoble 1 / CNRS, Grenoble, France, email: williamcvicars@gmail.com 

2 Current address: Research Center for Environmental Changes, Academia Sinica, Taipei, Taiwan 

The 17 O-excess (Δ 17 O) of ozone (O 3 ) serves as a useful marker in studies of atmospheric 

oxidation pathways; however, due to the expense and logistical complexity of the standard 

“cryogenic” measurement technique, natural variations in Δ 17 O(O 3 ) remain poorly constrained. 

Here we present a new method for the isotopic characterization of tropospheric O 3 using a 

simple, active air sampler with a nitrite-coated filter sampling substrate. This method is 

inexpensive and easy to implement in nearly any environment; furthermore, it does not involve 

the complex ozone collection technique utilized in prior isotopic studies of tropospheric O 3 . The 

coated filter method employs the aqueous phase O 3 /nitrite oxidation reaction (NO 2 - + O 3 —› NO 3 

- 

+ O 2 ) to obtain quantitative information on O 3 via the oxygen atom transfer to nitrate (NO 3 - ). The 

triple-oxygen isotope analysis of the NO 3 - produced during this reaction, achieved in this study 

using the bacterial denitrifier method, directly yields the Δ 17 O value transferred from O 3 , referred 

to as the “transferrable” Δ 17 O and denoted Δ 17 O(O 3 *). Isotope transfer experiments were 

conducted by exposing coated filters to O 3 of various known Δ 17 O values. These experiments 

reveal a strong linear correlation (r=0.97) between Δ 17 O(O 3 ) bulk and Δ 17 O(O 3 *) with a transfer 

function that is in close agreement with theoretical postulates that place 17 O-excess on only the 

terminal oxygen atoms of O 3 . Ambient tropospheric measurements at various spatial and 

temporal scales yield Δ 17 O(O 3 ) bulk values in close agreement with those obtained previously using 

the cryogenic trapping technique; however, the magnitude of variability found in these landmark 

studies is conspicuously absent from our first nitrite-coated filter results (Figure 1). In fact, the 

standard deviation of all ambient Δ 17 O(O 3 ) bulk measurements is close to the uncertainty estimated 

for the method (1.7‰), indicating that the observed variations from the mean are not significant. 

However, a more complete understanding of the nature and scale of variability in tropospheric 

Δ 17 O(O 3 ) will require a great number of observations in different contexts and environments. 

Using this method, we can now investigate the potential seasonal, diurnal, and spatial features of 

the ozone 17 O-excess and also search for processes to explain these variations. Future research 

using the nitrite-coated filter method will thus undoubtedly lead to a more robust theoretical 

framework for interpreting natural Δ 17 O variation and transfer in the atmosphere. 

! 17 O(O 3 ) bulk (‰) 

60 

50 

40 

30 

20 

10 

0 

n=7 n=29 

Pasadena La Jolla 

Johnston and Thiemens 

(1997) 

n=6 

White 

Sands 

n=47 

Urban Air Grenoble 

Krankowsky 

et al. (1995) 

n=39 

This 

study 

Figure 1: Comparison of 

Δ 17 O(O 3 ) bulk measurements 

obtained using the 

cryogenic technique with 

those found in this study. 

The box plot indicates the 

median (line), interquartile 

range (box), maximum, and 

minimum values. The mean 

value is displayed (circle), 

as well as the number of 

data-points for each site. 

Page 93


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CLUMPED ISOTOPE ANALYSIS OF MODERN MARINE CARBONATES AND SILURIAN 

BRACHIOPODS 

Ulrike Wacker 1 , Jens Fiebig 1 , Bernd Schoene 2 , Axel Munnecke 3 , Michael M. Joachimski 3 , Alan D. 

Wanamaker 4 . 1 Department of Geosciences, Goethe University Frankfurt, Germany, 

U.Wacker@em.uni-frankfurt.de. 2 Institute of Earth Sciences, Johannes Gutenberg-University, 

Mainz, Germany. 3 GeoZentrumNordbayern, Friedrich-Alexander-University, Erlangen, Germany. 

4 Department of Geological and Atmospheric Sciences, Iowa State University, Ames, USA 

Several calibrations of the carbonate clumped isotope thermometer have been published so far, 

based on the analysis of synthetically, biogenically and abiogenically precipitated crystals (Eiler, 

2011, and references therein). Different modern biogenic calcites and aragonites for which growth 

temperatures were constrained independently, confirm the trend between T growth and Δ 47 of 

synthetic carbonates reported by Ghosh et al. (2006). Dennis & Schrag (2010), however, received 

a relationship between growth temperature and Δ 47 for inorganically precipitated calcite that differs 

from the Ghosh et al. (2006) line, even if both calibrations are projected to the absolute reference 

frame (Dennis et al., 2011). Contrary to the Ghosh et al. (2006) calibration, the slope of the Dennis 

& Schrag (2010) T-Δ 47 correlation line is close to that predicted by theoretical evaluations (Guo et 

al., 2009). 

We have analyzed different modern marine carbonates (foraminiferas, bivalves, brachiopod, cold 

seep carbonates) and an eggshell of an ostrich for their Δ 47 signatures using a partly automated 

common acid bath (reaction temperature of 90°C). Precipitation temperatures of sampled material 

were constrained independently and range from 6 to 38°C. The slope of our temperature-Δ 47 

relationship for marine calcites is very close to both, to that reported by Guo et al. (2009) and to 

the Dennis & Schrag (2010) calibration projected to the absolute scale (Dennis et al., 2011), with 

absolute Δ 47 values being slightly more positive than those theoretically predicted. Our aragonite 

calibration line based on A. islandica is almost identical to the theoretical evaluation. 

Inter alia, we are addressing the carbonate clumped isotope thermometer to Silurian brachiopod 

shells from Gotland. These fossils were described as being well preserved, both ultrastructurally 

and chemically (e.g., Samtleben et al., 1996; Wenzel & Joachimski, 1996; own results). We 

receive apparent crystallization temperatures of 30 - 70°C and 30 - 60°C applying our own calcite 

calibration and the Ghosh calibration recalculated by Dennis et al. (2011), respectively. These 

results may indicate that isotopic clumping inside the brachiopod shells was at least partly affected 

by diagenetic processes. We are currently applying additional methods such as SEM, CL, 

nanofocus-CT and a screen for trace elements to distinguish between primary and secondary 

calcite. 

Dennis & Schrag (2010) GCA 74, 4110-4122. Dennis et al. (2011) GCA 75, 7117-7131. Eiler 

(2011) QSR 30, 3575-3588. Ghosh et al. (2006) GCA 71, 2736-2744. Guo et al. (2009) GCA 73, 

7203-7225. Samtleben et al. (1996) IJES 85(2), 278-292. Wenzel & Joachimski (1996) PPP 

122(1-4), 143-166. 

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SITE-SPECIFIC 2 H/ 1 H ANALYSIS BASED ON SOLID-STATE NMR: APPLICATIONS IN 

COSMO/GEO/BIOCHEMISTRY 

Ying Wang 1 , George Cody 1 , Conel M. O’ D. Alexander 2 , Marilyn Fogel 1 , Bjørn Mysen 1 . 1 

Laboratory, Carnegie Institution of Washington (ywang1@ciw.edu), 2 Department of Terrestrial 

Magnetism, Carnegie Institution of Washington. 

Solid-state NMR offers a natural probe for site-specific isotope analysis of 

macromolecular and amorphorous materials. Compared to mass-spectrometer-based methods, it is 

non-destructive, free of isotope fractionation, and applicable to almost all solid samples. We have 

developed a solid-state 2 H NMR experimental protocol that greatly enhances the signal-to-noise 

ratio and removes 2 H quadruple interactions. Combined with 1 H NMR, this method enables several 

applications of site-specific 2 H/ 1 H analysis, which are summarized below. 

(1) The insoluble organic matter from two carbonaceous chondrites, Murchison and 

GRO95577, was analyzed for 2 H/ 1 H fractionation between aliphatic and aromatic positions 1 . The 

δ 2 H value was estimated to be 1255‰ and 605‰, respectively, for aliphatic and aromatic 

positions in Murchison, and 4800‰ and 1260‰ for the corresponding positions in GRO95577. Ab 

initio computer simulation (B3LYP/6-311g**) indicates that, to produce the observed 

fractionation by equilibrium isotope effect, the temperature needs to be around 20-25 K which 

would be too low for reversible hydrogen exchange reactions. It is more likely to be a coldchemistry 

signature that has been modified by hydrothermal alteration in parent body. 

(2) A series of experiments was conducted to investigate 2 H/ 1 H fractionation between 

dissolved H species in silicate glasses 2 . The starting material was a dry synthetic glass (Na 2 O · 

4SiO 2 ) which was mixed with 3, 6, or 9 wt% water of varying 2 H/ 1 H ratios and then equilibrated at 

1400˚C and 1.5 GPa, followed by quenching to a glass at a rate of ~100˚C/s. The majority of 2 H 

was found between 12 – 16 ppm, a frequency range featured by long O-H bond length and strong 

hydrogen bonding which likely result from being associated with Na + . In contrast, 1 H was mostly 

found between 4 – 6 ppm, indicating short O-H bonds in Si-OH groups and molecular water. The 

apparent fractionation between Na + -associated and non-associated positions varies from 3.5 to 5 

and is not correlated with total H content in the glass. 29 Si NMR reveals no change in the 

distribution of Q species with varying 2 H/ 1 H ratios, which suggests the observed site-specific 

fractionation is unlikely related to depolymerization of the silicate network. 

(3) By growing E. coli on selectively 2 H-enriched substrates, we were able to quantify 2 H 

incorporation into different molecular positions. When the media water was labeled by 10% 2 H, 

the 2 H uptake by membrane lipids, aliphatic H in proteins, and the non-aliphatic H positions is 

6.2%, 2.2%, and 6.0%, respectively. When the glucose substrate is labeled with 10% 2 H, the 

corresponding 2 H contents are 1.9%, 1.4%, and 2.5%. Aliphatic H in proteins is significantly 2 H- 

depleted relative to fatty acids by up to 650‰. We suggest this is probably due to the dynamic 

regulation of central metabolic pathways that tends to enrich 2 H in the slowly accumulated 

membrane lipids than in the fast synthesized amino acids through incorporation of water H. 

Potential isotope discrimination during protein recycle might also contribute to the observed 2 H 

depletion in proteins. Non-aliphatic H positions as a whole exhibit similar net fractionation as the 

lipids, which is probably due to their generally high exchangeability with water. 

1. Wang Y., Kebukawa Y., Cody G., and Alexander C. M. O’D. Deuterium speciation in chondritic organic solids: a 

relic of cold molecular processes. (2011) Lunar and Planetary Science Conference. 

2. Wang Y., Cody S., Cody G., and Mysen B. (2011) A multinuclear ( 1 H, 2 H, and 29 Si) solid-state NMR study on 

Hydrogen isotope speciation in hydrous sodium silicate glasses. AGU. 

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ISI 2012: 18- 22 June 2012 



ELUCIDATING SOURCE PROCESSES OF N 2 O FLUXES FOLLOWING GRASSLAND-TO-FIELD- 

CONVERSION BY MEASURING AND MODELING ISOTOPOLOGUE SIGNATURES OF SOIL- 

EMITTED N 2 O 

Reinhard Well, Greta Roth, Dominika Lewicka-Szczebak, Anette Giesemann, Heiner Flessa. 

Johann Heinrich von Thünen-Institut, Bundesforschungsinstitut für Ländliche Räume, Wald und 

Fischerei Institut für Agrarrelevante Klimaforschung, Bundesallee 50, 38116 Braunschweig, 

Deutschland 

High N 2 O fluxes after conversion of grassland to arable land often causes enhanced nitrous 

oxide (N 2 O) emissions to the atmosphere. The processes of N 2 O turnover (nitrification, production 

by bacterial or fungal denitrifiers, bacterial reduction to N 2 ) are difficult to identify, however. 

Isotopologue signatures of N 2 O such as δ 18 O, average δ 15 N (δ 15 N bulk ) and 15 N site preference (SP = 

difference in δ 15 N between the central and peripheral N positions of the asymmetric N 2 O 

molecule) can be used to characterize N 2 O turnover processes using the known ranges of isotope 

effects of the various N 2 O pathways. 

We aim to evaluate the impact of grassland-to-field-conversion on N 2 O fluxes and the governing 

processes by measuring isotopologue values of emitted N 2 O. Moreover, we want to test if 

modelling N 2 fluxes based on these data yields plausible results. 

At two sites, in Kleve (North Rhine-Westphalia, Germany, conventional farming) and Trenthorst 

(Schleswig-Holstein, Germany, organic farming), a four times replicated plot experiment with (i) 

mechanical conversion (ploughing, maize), (ii) chemical conversion (broadband herbicide, maize 

per direct seed) and (iii) continuous grassland as reference was started in April 2010. In Trenthorst 

we additionally established a (iv) field with continuous maize cultivation as further reference. 

Over a period of two years, mineral nitrogen (N min ) content was measured weekly on soil samples 

taken from 0-10 cm and 10-30 cm depth. Soil water content and N 2 O emissions were measured 

weekly as well. Gas samples were collected using a closed chamber system. Isotope ratio mass 

spectrometry was carried out on gas samples from selected high flux events to determine δ 18 O, 

δ 15 N bulk and SP of N 2 O. 

δ 18 O and SP of N 2 O exhibited a relatively large range (32 to 72 ‰ and 6 to 34 ‰, respectively) 

indicating highly variable process dynamics. 

The data-set was grouped according to conditions favouring nitrification (low soil water content, 

high NH 4 -N content) or denitrification (high soil water content, high NO 3 -N content, high 

availability of organic C after tillage of the sward). Isotopologue patterns are compared to known 

isotope effects of possible turnover processes. Results showed that the data-set is promising to 

further constrain N 2 O processes by process-based isotope fractionation modelling. We will model 

N 2 fluxes based on measured N 2 O isotopologue values and isotope enrichment factors of N 2 O 

reduction to N 2 determined during a soil laboratory incubation study (Lewicka-Szczebak et al., 

2012). Plausibility of N 2 fluxes will be evaluated using measured factors controlling denitrification 

(soil moisture, temperature, mineral N-content). 

Lewicka-Szczebak, D. et al. (2012) Isotope fractionation factors controlling isotopologue signatures of soil-emitted N 2 O 

produced by denitrification processes of various rates. Abstract submitted to the <strong>Sixth</strong> <strong>International</strong> <strong>Symposium</strong> on 

Isotopomers. 

Page 96


ISI 2012: 18- 22 June 2012 



MASS-INDEPENDENT FRACTIONATION FROM PHOTOEXCITATION OF SO 2 BY 250 TO 330 NM 

BROADBAND RADIATION IN THE PRESENCE OF ACETYLENE 

Andrew Whitehill 1,2 , Harry Oduro 2 , Shuhei Ono 2 1 arwhite@mit.edu 2 Department of Earth, 

Atmospheric, and Planetary Sciences, Massachusetts Institute of Technology, 77 Massachusetts 

Avenue, Cambridge, MA 02139 

Mass-independent sulfur isotope (S-MIF) signatures are observed in Archean rocks and 

modern stratospheric sulfate aerosols and are generally attributed to photochemistry of sulfur 

dioxide. Laboratory photolysis experiments (Farquhar et al. 2001, Masterson et al. 2011) and 

spectroscopic measurements (Danielache et al. 2008) have shown that SO 2 photochemistry can 

produce S-MIF, but the underlying mechanisms are still poorly constrained. We excited SO 2 in 

the 250 to 330 nm region ( 1 B 1 1 A 1 and 1 A 2 1 A 1 transitions) using a xenon arc lamp and a 250 

nm long-pass filter. Following Luria et al. (1974), acetylene was used to trap triplet state SO 2 

( 3 SO 2 ) resulting from collision-induced intersystem crossing from the singlet states of SO 2 ( 1 SO 2 ). 

Experiments were carried out using a flow-through photochemical system with an acetylene partial 

pressure of 10 mbar, SO 2 partial pressures from 1.0 to 10 mbar, N 2 partial pressures of from 250 to 

1000 mbar, and a gas residence time of 40 seconds. 

The organo-sulfur aerosol products, expected to be sulphonic acids, produced large 

positive S-MIF signatures in both 33 S and 36 S (Δ 33 S up to 80‰ and Δ 36 S up to 100‰) with 

relatively small enrichments in 34 S (δ 34 S up to 25‰). Positive Δ 36 S values are not predicted from 

isotopologue self-shielding. The magnitude of the Δ 33 S signatures contrast with predictions based 

on isotopologue-specific cross-sections (Δ 33 S = -3‰ to 1‰ for 250 to 330 nm excitation, 

calculated from Danielache et al. 2008). In addition, experiments performed using a 300 nm shortpass 

filter and 305 nm long-pass filter show only minor wavelength dependence on the isotope 

effect in this region. This suggests that the S-MIF is associated with the post-excitation dynamics 

of SO 2 , possibly due to the various intersystem crossing or internal conversion reactions, as 

suggested previously for CS 2 (Zmolek et al. 1999). 

Although photochemistry in this region cannot explain the negative Δ 36 S/Δ 33 S values of S- 

MIF signatures in either Archean rocks or modern stratospheric aerosols, the excited-state 

photochemistry of SO 2 could have contributed to a signature dominated by direct 

photodissociation of SO 2 (190 to 220 nm, see Ono et al., this volume). Isotope signatures from the 

excited-state photochemistry of SO 2 could be preserved in an organic-rich atmosphere, as has been 

suggested for periods of the Archean (e.g. Zerkle et al. 2012), and changes in the relative 

contribution of the two isotope absorption bands of SO 2 could explain variations in Δ 36 S / Δ 33 S 

ratios during different periods of the Archean. 

Danielache, S.O. et al., J. Geophys. Res. 113, D17314 (2008). 

Farquhar, J. et al., J. Geophys. Res. 106, 32829 – 32839 (2001). 

Luria, M. et al., J. Phys. Chem. 78, 325 – 335 (1974). 

Masterson, A.L. et al., Earth Planet. Sci. Lett. 306, 253 – 260 (2011). 

Ono, S. et al., ISI 2012 Abstract 

Zerkle, A.L. et al., Nature Geosci. 5, 359 – 363 (2012). 

Zmolek, P. et al., J. Phys. Chem. A 103, 2477 – 2480 (1999). 

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STABLE WATER ISOTOPOLOGUES OF EAST ANTARCTIC (VOSTOK) SNOW SAMPLES: NEW 

INSIGHTS IN TEMPERATURE-δ 18 O RELATIONSHIP 

Renato Winkler 1* , Amaelle Landais 1 , Melanie Baroni 2 , Alexey Ekaykin 3 , Sonia Falourd 1 , Jean 

Jouzel 1 , Benedicte Minster 1 , Jean Robert Petit 4 , Frederic Prie 1 , and Camille Risi 5 

*renato.winkler@lsce.ipsl.fr. 1 Laboratoire des Sciences du Climat et de l’Environnement 

(IPSL/CEA/CNRS/UVSQ), Gif sur Yvette, France , 2 Cerege (CNRS, IRD), University of Aix- 

Marseille, College de France, Aix-En-Provence France, 3 Arctic and Antarctic Research Institute, 

St Petersburg, Russia, 4 Laboratoire de Glaciologie et Geophysique de l’Environnement, CNRS- 

UJF, St Martin d’Heres, France, 5 Laboratoire de Meteorologie Dynamique, Paris, France 

Reconstruction of past temperature from water isotopic records in deep ice cores in remote East 

Antarctica is limited by several reasons such as changes in precipitation seasonality, limited 

knowledge of water isotopic fractionation at low temperature, temporal changes in hydrological 

cycle, post-deposition effects and possible input of stratospheric water. In order to address these 

issues, we present stable water isotopologues (δ 18 O, δD and δ 17 O) of a snow pit at Vostok (78°27 

S, 106° 50 E) covering the period from 1950 to 2008, and compare these new data of inter annual 

resolution with the previously obtained seasonal and glacial/interglacial records of Landais et al. 

(2012 and 2008). Indeed, the combination of water isotopologues such as δ-excess (δD-8×δ 18 O) 

and 17 O-excess= ln(δ 17 O+1)-0.528×ln(δ 18 O+1)) are especially sensitive to organisation of the 

hydrological cycle, changes in kinetic vs. equilibrium fractionations and post-deposition effects. 

The relationships between δ 18 O, δ-excess and 17 O-excess display very distinguished patterns on 

the three different timescales. The results of the seasonal cycle suggest a much more important 

influence of temperature on δ-excess and 17 O-excess than previously assumed which is helpful to 

constrain fractionation conditions at very low temperature (Landais et al, 2012). However on the 

interannual timescale, the comparison of the strong variations in δ 18 O, δ-excess and 17 O-excess 

with on-site temperature data, evidence other mechanisms such as post-depositional effects or 

hydrological cycle reorganizations to play an important role in the distribution of stable water 

isotopologues at Vostok. 

Finally, we compare these results with general circulation model outputs including water 

isotopologues in order to test the capacity of such models to represent water isotopic composition 

in remote regions of East Antarctica. 

A. Landais, A. Ekaykin, E. Barkan, R. Winkler and B. Luz, Seasonal variations of 17 O-excess at the Vostok 

station (East Antarctica), Journal of Glaciology, 2012. 

Amaelle Landais, Eugeni Barkan and Boaz Luz. Record of d 18 O and 17 O-excess in ice from Vostok 

Antarctica during the last 150,000 years ,GRL, Vol. 35, 2008. 

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FACTORS CONTROLLING THE CARBON ISOTOPIC VARIATION OF CAFFEINE 

Chen Wu 1 , Keita Yamada 1 , Osamu Sumikawa 2 , Akiko Matsunaga 2 , Alexis Gilbert 1 , Naohiro 

Yoshida 1 . 1 Department of Environmental Chemistry and Engineering, Tokyo Institute of 

Technology, 4259 Nagatsuta-cho, Midori-ku, Yokohama, Kanagawa 226-8503, Japan 

chenwu.violet@gmail.com 2 National Institute of Vegetable and Tea Science, 2769 Kanaya, 

Shizuoka 428-8501, Japan 

Caffeine is one of the major alkaloids in tea plants (Camellia sinensis) accounting for 1%- 

5% of dry weight (Perva-Uzunalic et al. 2006). It is also acting as a natural pesticide in tea plants 

to prevent from the insects (Nathanson et al. 1984, Ashihara et al. 2001). The metabolism of 

caffeine in tea plants is controlled by many factors, such as, temperature, sun exposure, humidity, 

cultivars, etc. (Lee et al. 2010). At the room temperature, caffeine is more soluble in chloroform 

than in water, but it still has high solubility in water than other alkaloids in tea leaves. Therefore, 

we can always find high concentration of caffeine in tea beverages comparing with other 

compounds except catechins, a big chemical group in the tea leaves. 

Tea is one of the most popular beverages in the world. Drinking and making tea has a long 

historical culture especially in Asia. It is quite easily to find hundreds of different types, flavors 

and origins of tea in the markets where the prices of tea and tea making crafts has huge varieties. 

For the sake of protecting the tea markets several simple and accurate analytical protocols to 

discriminate the origins are requested. 

Stable isotope analysis is one of the effective analytical methods to discriminate the 

origins of food (Kawasaki et al. 2002, Kelly et al. 2002, Camin et al. 2004, Rossmann et al. 2000). 

Caffeine has been successful as an indicator for the origins of green coffee bean (Coffea arabica) 

using multi-element stable isotope analysis (Weckerle et al. 2002). We are trying to discriminate 

the origins of tea using the similar methodology. However, most of researches using stable isotope 

analysis did not take account of the factors controlling the stable isotope ratios, for instance, the 

seasonal variation of carbon isotopic ratios. 

Thus, we discussed the factors controlling the carbon isotopic variation of caffeine here. 

Several factors were contained: (1) environmental conditions including temperature, humidity, sun 

exposure and seasons, (2) tea cultivars and (3) process of making green tea. Our results indicated 

that all these factors had influences on the values of carbon isotope ratios of caffeine. 

Page 99


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MEASUREMENT METHOD FOR INTRAMOLECULAR CARBON ISOTOPIC DISTRIBUTIONS OF 

SOME C2 AND C3 METABOLITES 

Keita Yamada 1 , Alexis Gilbert 1 , Na Li 1 , Takanori Okuno 1 , Naohiro Yoshida 1 , Ryota Hattori 2 , 

Nariaki Wasano 2 , Satoshi Hirano 2 . 1 Interdisciplinary Graduate School of Science and 

Engineering, Tokyo Institute of Technology, yamada.k.ag@m.titech.ac.jp. 2 Central Laboratories 

for Frontier Technology, Center for Food Safety Science, Kirin Holdings Co. Ltd., 

A deeper understanding how intramolecular isotopic distributions of metabolites are created 

should improve insights into microbial and plant metabolisms. Since the pioneering study of 

Abelson and Hoering [1961], intramolecular carbon isotopic distributions of some important 

metabolites have been measured using chemical and/or thermal decomposition of metabolites into 

fragments followed by isotope ratio mass spectrometry (IRMS) of CO 2 converted from the 

fragments. This measurement method requires milligram levels of a target compound and 

cumbersome preparation. This drawback prevents to develop the intramolecular carbon isotopic 

analysis of metabolites. The advent of a gas chromatography-combustion-IRMS (GC-C-IRMS) 

technique has been overcome the obstacles to measure intramolecular carbon isotopic distributions 

in some important metabolites. Corso and Brenna [1997] first demonstrate the availability of the 

on-line pyrolysis-GC-C-IRMS to measure intramolecular isotopic distributions of methyl 

palmitate as a test compound. 

In this study, we present measurement methods to determine the intramolecular carbon 

isotopic distributions of some important metabolites including C2 compounds (acetic acid and 

acetaldehyde) and C3 compounds (acetone and alanine) using GC-C-IRMS. First, we refined the 

method for acetic acid, acetaldehyde and acetone which uses the combination of the off-line 

pyrolysis and GC-C-IRMS. Second, we examined the method for acetaldehyde and acetone using 

the on-line pyrolysis-GC-C-IRMS. Third, we examined the method for alanine using the 

combination of ninhydrin reaction and on-line pyrolysis-GC-C-IRMS for acetaldehyde. We can 

determine the intramolecular carbon isotopic distributions of alanine within the precision of 0.3‰ 

(1σ) for 0.8µmol of pure alanine. 

[1] Abelson P. H. and Hoering T.C. (1961) Carbon isotope fractionation in formation of amino 

acids by photosynthetic organisms. Proceedings of the National Academy of Sciences, USA 47, 

623-632. 

[2] Corso T.N. and Brenna J.T. (1997) High-precision position-specific isotope analysis. 

Proceedings of the National Academy of Sciences, USA 94, 1049-1053. 

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18 O 18 O AND 17 O 18 O IN THE ATMOSPHERE 

Laurence Y. Yeung, Edward D. Young, and Edwin A. Schauble. Department of Earth and Space 

Sciences, University of California, Los Angeles, CA 90095, 

The isotopic composition of atmospheric O 2 reflects the balance between photosynthesis, 

respiration, and the hydrologic cycle over millennial timescales. The Quaternary oxygen-isotope 

budget in atmospheric O 2 , however, is under-constrained, and measurements of the 18 O 18 O and 

17 O 18 O content in the atmosphere will provide additional information. 

For instance, the tendency for 18 O- 18 O and 17 O- 18 O bonds to form upon photosynthesis is 

expected to be insensitive to the isotopic composition of the source water, as C-O bond ordering in 

carbonates has been shown to be independent of the isotopic composition of carbonate source 

water [1]; water has no O-O bonds to pass on, so photosynthetic O 2 cannot inherit a bond-ordering 

signature from its source water. 

Oxygen consumption via respiration, in contrast, is expected to alter the bond ordering in O 2 . 

Microbial respiration and photorespiration fractionate oxygen isotopologues in a manner similar to 

Knudsen diffusion, leaving the residue between +14-30‰ and +7-15‰ enriched in δ 18 O and δ 17 O, 

respectively [2,3] resulting in the well-known atmospheric Dole effect. If the mass dependence of 

respiration mimics that of diffusion, then 18 O 18 O and 17 O 18 O in the fractionated residue should be 

depleted relative to the stochastic distribution [1]. Thus, the Dole effect may manifest itself as a 

depletion in 18 O 18 O and 17 O 18 O relative to the stochastic distribution in atmospheric O 2 . 

We examined the exceedingly rare 18 O 18 O and 17 O 18 O isotopic variants of O 2 in tropospheric 

air. We find that these species are enriched relative to the stochastic distribution of isotopes – 

opposite in sign from signatures predicted to be imposed by the biosphere. We demonstrate, with 

laboratory experiments, that bond ordering in atmospheric O 2 is likely governed by autocatalytic 

O( 3 P) + O 2 isotope-exchange reactions that cycle through the atmospheric O 2 reservoir on decadal 

timescales. Our analysis of the atmospheric budget suggests that trends in O-O bond ordering over 

geologic time may be sensitive to tropospheric O( 3 P) concentrations, tropopause temperature, and 

stratosphere-troposphere exchange flux, offering constraints on the abundance of short-lived trace 

gases and the strength of circulation in the ancient atmosphere. 


[1] Eiler, J. M. (2007) Earth Planet. Sci. Lett.262, 309-327. 

[2] Guy, R. D. et al. (1989) Planta 177, 483-491. 

[3] Kiddon, J., et al. (1993) Global Biogeochem. Cycles 7, 679-694. 

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DEVELOPMENT OF A THREE DIMENSIONAL ATMOSPHERIC SULFUR ISOTOPIC MODEL 

Chisato Yoshikawa 1 , Sebastian O. Danielache 1 , Yuichiro Ueno 1 , Kengo Sudo 2 , Kentaro Ishijima 3 , 

Masayuki Takigawa 3 , Naohiro Yoshida 1 . 1 Interdisciplinary Graduate School of Science and 

Engineering, Tokyo institute of Technology, yoshikawa.c.aa@m.titech.ac.jp, 2 Graduate School of 

Environmental Studies, Nagoya University, 3 Research Institute for Global Change, JAMSTEC 

Sulfate aerosols are important because of its role to direct and indirect radiative forcing. 

An accurate estimation of the global sulfur budget and a better understanding of sulfate production 

processes are essential to precise predictions of future climate change. There have been several 

observations and model studies that have examined the atmospheric sulfur budget. However, the 

uncertainly of the estimation is still large because of the complicated reactions and heterogeneous 

sources. In this study we aim to reduce the uncertainty and to improve the understanding of sulfate 

production processes by using a prognostic model constrained by sulfur isotopic ratio. We have 

introduced sulfur isotopes ( 32 S and 34 S) into a chemistry-coupled atmospheric general circulation 

model and set isotopic fractionation effects obtained by theoretical calculations and isotopic ratios 

of emission sources reported by several observations to the model (Fig. 1). Here, we present our 

results from a three dimensional atmospheric sulfur isotopic model and attempt to estimate 

isotopically correct fluxes of each emission source derived from the difference between model 

results and observed values. 

Figure 2: Schematic view of the atmospheric sulfur isotopic model 

Stable Isotopes: Natural and Anthropogenic Sulfur in the Environment, SCOPE 43, edited by H. R. Kruose, L. N. 

Grinenko, and F. Newman (Wiley, Chichester, 1991), p. 165. 

Schmidt J.A. et al. (2011) Predictions of the sulfur and carbon kinetic isotope effects in the OH + OCS reaction, CPL, 

531, 64-69 

Hattori S. et al. (2011) Ultraviolet absorption cross sections of carbonyl sulfide isotopologues OC 32 S, OC 33 S, OC 34 S and 

O 13 CS: isotopic fractionation in photolysis and atmospheric implications, ACP, 11, 10293–10303. 

Harris E. et al. (2012) Fractionation of sulfur isotopes during heterogeneous oxidation of SO 2 on sea salt aerosol: a new 

tool to investigate non-sea salt sulfate production in the marine boundary layer, ACP, 12, 2707-2742. 

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VARIATIONS OF 13 C 16 O 18 O AND ITS CONTROLLING FACTORS IN THE ATMOSPHERE OF 

YOKOHAMA, JAPAN BASED ON THE OBSERVATION FROM 2007 TO 2011 

Naizhong Zhang 1 , Keita Yamada 2 , Naohiro Yoshida 3, 1 Tokyo Institute of Technology, 

zhang.n.aa@m.titech.ac.jp 2,3 Tokyo Institute of Technology 

For better understanding the behavior of CO 2 in the atmosphere, study of the budget of 

atmospheric CO 2 is necessary. Available published tools have been concentration, the O 2 /N 2 ratio 

of air, isotopic values such as δ 13 C, δ 18 O, △ 14 . However, because of the complexity and 

variability of CO 2 sources and sinks in the atmosphere, these constraints are not enough especially 

for the urban atmosphere. Additional constraints should be developed in this field to calculate the 

contribution of each source and sink more accurate and rigorous. Recently, ‘mass 47 anomaly’ 

(△ 47 ) was raised as a new constraint and it was defined as the deviation of the abundance of mass 

47 isotopologues from expected for a random distribution of isotopes [1][2] . 

Affek et al. [2] observed the seasonal and diurnal variations of 16 O 13 C 18 O in air from Pasadena, USA 

during 2004 and 2005, and they found lower △ 47 values of winter than that of summer in 

background air. However, inconsistently seasonal variations were observed in urban atmosphere of 

Yokohama from October, 2007 to January, 2009 and June, 2010 to July, 2011 (Lower values in 

winter were not observed in Yokohama; △ 47 values were mostly between 0.90‰ and 1.00‰ while 

between 0.75‰ and 1.00‰ by Affek et al. [2] ). This suggests that seasonal trends of △ 47 are 

different in different regions due to the complex atmospheric system which is affected by 

multivariate environmental parameters and various constitutions of CO 2 sources. 

In the further discussion, we analyze the observation from June, 2010 to July, 2011 concretely. 

The results shown that seasonal trend of △ 47 observed was consistent with that under 

thermodynamic equilibrium, which suggests that temperature is an important parameter to control 

△ 47 variations in the atmosphere and approach them to the thermodynamic equilibrium. At the 

same time, by the mass balance model, we find that fossil fuel combustion is an important source 

to control △ 47 variations and cause some extremely low values, where we observed in Yokohama, 

it caused lower △ 47 values by 0.01‰ to 0.11‰. Moreover, we observed higher △ 47 values in the 

summer of 2011 but the controlling factors are not clear at present. However, there are some 

evidences suggesting that humidity or ocean-air exchange mechanism probably produced this kind 

of high △ 47 values and the vapor/ocean-CO 2 equilibrium effect should be estimated in the further 

study to interpret this phenomenon. 

References 

[1] Eiler J. M. and Schauble E. (2004) Geochimica et Cosmochimica Acta 68(23), 4767-4777 

[2] Affek H. P., Xu X., and Eiler J. M., (2007) Geochimica et Cosmochimica Acta 71, 5033-5043. 

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ISOTOPOMER ANALYSIS OF N 2 O ACCUMULATED IN TEA FIELD SOIL IN SHIZUOKA, CENTRAL 

JAPAN 

Yun Zou 1 , Yuhei Hirono 2 , Yosuke Yanai 2 , Shohei Hattori 1 , Sakae Toyoda 1 , Naohiro Yoshida 1 . 

1 Tokyo Institute of Technology, zou.y.aa@m.titech.ac.jp, 2 NARO Institute of Vegetable and Tea 

Science 

Nitrous oxide (N 2 O) is an increasing greenhouse gas in the troposphere and a potential 

destroyer of the stratospheric ozone layer. Agricultural soil is a large contributor of global N 2 O as 

a result of nitrogen (N) fertilizer application. In Japan, tea fields are amended with the highest 

level of N fertilizer among agricultural soils, causing soil acidification with large N 2 O flux. 

Therefore, tea field is one of the suitable agricultural soils for analyzing N 2 O dynamics. This study 

purpose is to investigate the processes leading to high N 2 O production in the tea field. 

To analyze N 2 O concentration and isotopomer ratios, soil gas in Shizuoka tea field was 

collected by silicone tube device from February to August 2011 with an interval of one week. To 

analyze mineral N (NH 4 + and NO 3 - ) concentration and isotopic analyses, soil samples were freshly 

collected from surface 0-20 cm depth and then sieved for extraction with KCl solution. 

Combination of fertilization, precipitation, and temperature rise enhanced N 2 O concentration, 

especially in the topsoil. Based on N 2 O isotopomer ratios, the low site preference (SP, indicating 

the difference of 15 N/ 14 N ratio between central (a) and terminal (b) nitrogen, i.e. b N a NO) ranging 

from 1.4‰ to 9.8‰ suggested that the contribution of nitrite (NO - 2 ) reduction was greater than 

that of hydroxylamine (NH 2 OH) oxidation when N 2 O concentration was high (ranging from 5.7 to 

88.7 ppmv (parts per million by volume, mL L -1 )). The ammonium (NH + 4 ) concentration decrease 

and N 2 O concentration increase occurred simultaneously on 31 May (after fertilization on 26 May) 

and 25 July (after fertilization on 8 July), suggesting that ammonia oxidizers, instead of 

- 

heterotrophic bacteria, can participate in NO 2 reduction. Moreover, the positive correlation 

between δ 15 N bulk and SP (slope = 1.032, R 2 = 0.908, n = 8) obtained on 31 May and 7 June (after 

fertilization on 26 May) suggests the reduction of N 2 O to N 2 . However, during the same 

observation period, even though the positive correlation between δ 15 N bulk and δ 18 O (slope = 0.977, 

R 2 = 0.981, n = 8) and that between SP and δ 18 O (slope = 0.887, R 2 = 0.948, n = 8) were observed, 

the slopes are different from previous reported pure incubation data, suggesting that N 2 O reduction 

occurred simultaneously with N 2 O production because oxygen (O) might exchange between soil 

water (H 2 O) and NO - 2 . N 2 O reduction was also observed during 25 July to 2 August (after 

fertilization on 8 July). Furthermore, higher SP values observed on 31 May suggest fungal 

denitrification might contribute to N 2 O production. 

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