North to Alaska - for Petroleum News

Page 2 

North to Alaska: Geoscience, Technology and Natural Resources

North to Alaska: Geoscience, Technology and Natural Resources Page 3 

Welcome: A message from our co-chairs 

It is with great pleasure that we announce the joint meeting of 

the Cordilleran Section – GSA, the Pacific Section – AAPG, and the 

Western Region – SPE. 

The theme of the meeting “North to Alaska: Geoscience, 

Technology, and Natural Resources”highlights the challenges, high 

stakes, and excitement offered through technology to deliver our 

energy and natural resources in the future. 

The broad format of this joint conference promotes emphasis 

on innovation and cross-discipline approaches in energy and natural 

resource development.With a wide span of technical presentations, 

forum topics, short courses, field trips, poster sessions, and 

exhibits, this meeting is sure to offer something for all professionals 

involved in the petroleum and natural resource industries, as 

well as those involved in Cordilleran and Arctic geoscience studies. 

A meeting with an ambitious schedule such as assembled for 

this joint conference, including all the logistical as well as technical 

contributions, would be little short of a disaster without an army of 

volunteers and generous sponsors. 

The contributions of our Sponsors have allowed us to plan a 

meeting of professional caliber and offer a program unique to 

Alaska. 

Last, with great pleasure and gratitude 

we acknowledge the volunteers from the 

local geoscience and engineering community, 

from the state of Alaska, and all those 

from the organizations outside of Alaska for 

all the hard work and cooperation to see 

that this meeting is a success. 

Welcome all! 

Pacific Section AAPG Co-Chair 

Greg Wilson 

ConocoPhillips Alaska 

Cordilleran Section GSA Co-Chair 

Jeanine M. Schmidt 

U.S. Geological Survey 

Western Region SPE Co-Chair 

Bill Van Dyke 

AK Dept. of Natural Resources 

Keynote address 

3D Seismic Expression of Deep Water Depositional Elements: Reducing the Risk of Lithology Prediction 

A 

By HENRY POSAMENTIER 

Chief Geologist and Distinguished Advisor 

for Anadarko Petroleum 

nalyses of 3-D seismic data can yield 

significant insights with regard to 

spatial and temporal relationships of 

near-seafloor depositional elements 

in deep-water settings. These analyses can 

be based on a broad range of horizon 

attributes, such as amplitude, time/depth 

structure, dip azimuth, dip magnitude, curvature, 

and roughness, as well as interval 

attributes such as frequency and amplitude 

distribution, and seismic facies based on 

waveform. 

The great complexity of deep-water 

depositional environments can be simplified 

by grouping depositional elements into 

five major categories: 1) turbidity-flow leveed 

channels, 2) channel-overbank sediment 

waves and levees, 3) frontal 

splays/distributary channel complexes, 4) 

crevasse splay complexes, and 5) debrisflow 

channels, lobes and sheets. Each depositional 

element type displays a unique 

morphology and seismic-stratigraphic 

expression.Their reservoir architecture is a 

function of the interaction between sedimentary 

process, sea-floor morphology, and 

sediment grain size distribution. Each 

depositional element is associated with a 

characteristic suite of lithofacies that can 

be predictable. Principal sand habitats in 

deep-water settings include channels, fontal 

splays, and crevasse splays. 

Turbidity-flow leveed channels can 

range from nearly straight to highly sinuous; 

channel meanders in most instances 

migrate down-system. In some instances, 

high-sinuosity channels are associated with 

channel-overbank sediment wave development, 

especially in association with outer 

channel bends.Where levees are low, to the 

point where they can no longer be 

resolved seismically, high-sinuosity channels 

feed frontal splays/low-sinuosity distributary 

channel complexes. Low-sinuosity distributary 

channel complexes commonly are 

expressed as lobate sheets.A variation on 

frontal splays, but located on overbank settings 

associated with leveed channels, are 

crevasse splay deposits, which comprise 

smaller lobeforms associated with levee 

crevasses commonly located at outer channel 

bends. 

Debris-flow deposits, commonly characterized 

by poor reservoir quality, can form 

low-sinuosity channel fills, elongate lobes, 

and sheets and are characterized seismically 

by contorted, chaotic, low-amplitude 

reflection patterns that commonly overlie 

striated/grooved pavements. 

Henry W. Posamentier 

is the Chief Geologist 

and Distinguished 

Advisor for Anadarko 

Petroleum Corporation. 

Prior to joining Anadarko 

in 2001, he was with 

Veritas Exploration 

Services (2000-2001), the 

Atlantic Richfield Co. 

(1991-2000), Exxon Production Research Co. and 

Esso Resources Canada, Ltd. (1979-1991), and at 

Rider University, Assistant Professor of Geology 

(1974-1979). 

Dr. Posamentier’s research interests have 

been in the fields of sequence stratigraphy and 

depositional systems analysis, where he has published 

widely. Most recently, he has employed an 

interdisciplinary approach to geologic prediction 

using 3D seismic visualization integrated with 

borehole data to interpret depositional systems 

and develop basin fill histories, in particular with 

reference to deep-water depositional settings. 

His current responsibilities involve ensuring integration 

of appropriate technologies into the 

exploration process. In 1971-1972, Dr. 

Posamentier was a Fulbright Fellow to Austria. 

He has served as an AAPG Distinguished 

Lecturer to the United States (1991-1992), an 

AAPG Distinguished Lecturer to the former 

Soviet Union (1996-1997), and an AAPG 

Distinguished Lecturer to the Middle East (1998- 

1999).

NORTH TO ALASKA 

Released May 3, 2006 

Special publication for a joint 

meeting of the Cordilleran 

Section, GSA, the 

Pacific Section, AAPG; and the 

Western Region, SPE. The 

theme of the meeting 

is "North to Alaska: 

Geoscience, Technology, and 

Natural Resources." 

North to Alaska was produced by 

Petroleum News 

MAILING ADDRESS: 

PO Box 231651 

Anchorage, AK 99523-1651 

Phone: (907) 522-9469 

Fax: (907) 522-9583 

Email: 

circulation@PetroleumNews.com 

Web page: 

www.PetroleumNews.com 

DAN WILCOX 

CEO 

MARY LASLEY 

CFO 

KAY CASHMAN 

Publisher 

KRISTEN NELSON 

EDITOR-IN-CHIEF 

AMY SPITTLER 

EDITOR 

SUSAN CRANE 

ADVERTISING DIRECTOR 

STEVEN MERRITT 

PRODUCTION DIRECTOR 

TOM KEARNEY 

AD & COVER PRODUCTION 

Cover Photo: David Lepain standing on an 

outcrop of Lower Cretaceous Nanushuk 

Formation sandstone at Tuktu Bluff in the 

Brooks Range Foothills. Photo courtesy 

David Houseknecht 

23 

3 

3 

6 

6 

6 

7 

Welcome: A message from our 

co-chairs 

Keynote address 

Schedule of events 

Technical program 

The Brooks Range Orogen: A 

Symposium in Honor of Gil Mull 

Theme sessions 

9 

10 

12 

13 

13 

14 

About Anchorage, including 

spouse and guest activities 

Field trips 

Short courses 

Student mentor program 

Student awards 

Exhibit map


AROUND ALASKA 

16 Opportunities abound at upcoming lease sales 

State tracts available in the May North Slope 

foothills and Cook Inlet basin areawide lease 

sales include underexplored areas 

20 Undiscovered riches in Beaufort, Chukchi seas 

Structures larger than Prudhoe Bay exist in 

regions that extend the prolific onshore 

petroleum systems of northern Alaska 

23 Gil Mull: A modern-day rock sleuth 

Petroleum geologist recounts 40 years working 

in the field in northern Alaska 

29 New assessment released for Alaska OCS 

Results from new model are similar in overall 

estimated resources 

29 Alaska sales set May 24 

32 Burger delivers 

MMS reappraises Chukchi well; may be largest 

hydrocarbon find on Alaska OCS

Page 6 

North to Alaska: Geoscience, Technology and Natural Resources 

Joint Technical Conference 

Pacific Section – AAPG 

Cordilleran Section – GSA 

Western Region – SPE 

May 7-10, 2006 • Anchorage Hilton Hotel 

North to Alaska: Geoscience, 

Technology and Natural Resources 

Technical program 

There are 31 oral sessions and 14 

poster sessions during this meeting. Oral 

sessions take place in the Aleutian and 

Alaska Rooms (2nd floor) and in the 

Aspen, Spruce, Birch-Willow, Fireweed, 

and Lupine rooms (1st floor) in the West 

Tower of the Anchorage Hilton Hotel. 

Poster sessions are located in the Denali 

Room (2nd floor), across from the 

exhibits area (Bristol Bay Ballroom), and 

are a half-day in duration. Poster presenters 

are expected to be present for two 

hours (9-11 a.m. or 2-4 p.m.). 

Oral presentations in most sessions 

will be 20 minutes in length, including 3 

to 5 minutes for discussion and change 

of speakers. Some SPE sessions will have 

30-minute presentations. 

Symposium 

The Brooks Range Orogen: A Symposium 

in Honor of Gil Mull 

The Brooks Range, one of the outstanding 

fold-thrust belts of North 

America, was caused by thrusting of 

oceanic rocks northward onto the Arctic 

Alaska continental margin in the Jurassic 

and Early 

Cretaceous. Gil Mull 

spent more than 

four decades mapping 

the complexities 

of this fascinating 

fold-thrust belt 

and made many significant, 

fundamental 

contributions to its 

Gil Mull 

stratigraphy, structural 

geology, tectonics, 

and petroleum geology. 

Over the course of his career, Gil has 

been a tireless advocate of field-based 

research focused on subjects of shared 

interest to academia and industry and has 

ALAN BAILEY 

Schedule continues on page 8


inspired and sponsored multiple generations 

of students to undertake field-based 

research projects in northern Alaska. 

For more information:Tom Moore, U.S. 

Geological Survey, tmoore@usgs.gov, 650- 

329-5713; Marwan Wartes,Alaska Division 

of Geological and Geophysical Surveys, 

marwan_wartes@dnr.state.ak.us, 907-451- 

5056. 

Theme sessions 

Joint: Pacific Section, AAPG and 

Cordilleran Section, GSA 

Foreland Basin Systems:Archives of 

Coupled Structural and Sedimentary 

Processes. Marwan Wartes,Alaska 

Division of Geological and Geophysical 

Surveys, marwan_wartes@dnr.state.ak.us, 

907-451-5056. 

Forearc Basins:Tectonostratigraphy 

and Resource Potential. Bob Swenson, 

Alaska Division of Oil and Gas, 

robert_swenson@dnr.state.ak.us, 907-451- 

5001. 

Geology of the Circum-Arctic.Tom 

Homza, Shell E&P Co., 

thomas.homza@shell.com, 907-770-3701; 

Jim Clough,Alaska Division of Geological 

and Geophysical Surveys, 

jim_clough@dnr.state.ak.us, 907-451- 

5030. 

Active Tectonics of the Northern 

Cordillera. Peter Haeussler, U.S. 

Geological Survey, pheuslr@usgs.gov, 907- 

786-7447. Coordinates with Chapman 

conference on Southern Alaska active tectonics 

to follow this meeting. 

Late Paleozoic–Early Mesozoic 

Paleogeography of Northern Alaska. Julie 

Dumoulin, U.S. Geological Survey, 

dumoulin@usgs.gov, 907-786-7439; Mike 

Whalen, University of Alaska–Fairbanks, 

mtwhalen@gi.alaska.edu, 907-474-5302. 

Cordilleran Section, GSA 

New Insights into the Origin and 

Evolution of the Northern Cordilleran 

Pericratonic Terranes. Cynthia Dusel- 

Bacon, U.S. Geological Survey, 

cdusel@usgs. gov, 650-329-5719; JoAnne 

Nelson, British Columbia Geological 

Survey, joanne.nelson@gems1.gov.bc.ca, 

250-952-0438. 

Wrangellia—Tectonics and 

Metallogeny, 30 Years of Progress. Jeanine 

Schmidt, U.S. Geological Survey, 

jschmidt@usgs.gov, 907-786-7494; Murray 

Hitzman, Colorado School of Mines, 

mhitzman@mines.edu, 303-384-2127; 

Jason Price, Colorado School of Mines. 

Accreted Terranes of Western North 

America:An Update on Current Research 

on the Construction of the Cordillera. 

Robert B. Blodgett, U.S. Geological 

Survey, rblodgett@usgs.gov, 907-786-7416; 

Erik C. Katvala, University of Calgary, eckatval@ucalgary.ca. 

Environmental Issues Associated with 

Mineralized Regions. LeeAnn Munk, 

University of Alaska–Anchorage, 

aflm@uaa.alaska.edu, 907-786-6895; 

Bronwen Wang, 

U.S. Geological Survey, bwang@usgs.gov, 

907-786-7110. 

High Latitude-Altitude Hydrogeology 

and Weathering. Bronwen Wang, U.S. 

Geological Survey, bwang@usgs.gov, 907- 

786-7110. 

Tectonic Setting of Mineral 

Occurrences in the Northern American 

see next page

Page 8 

Cordillera. Bill McClelland, University of 

Idaho, mcclell@uidaho.edu, 208-885-4704; 

Richard Goldfarb, U.S. Geological Survey, 

gold-farb@usgs.gov, 303-236-2441. 


Schedule continues 

Geoscience Education and Public 

Outreach in Alaska—Unique Problems, 

Unique Solutions. Catherine L. Hanks, 

University of Alaska–Fairbanks, 

chanks@gi.alaska.edu, 907-474-5562. 

Volcano Hazards and Monitoring. Steve 

McNutt, University of Alaska–Alaska 

Volcano Observatory, 

steve@giseis.alaska.edu, 907-474-7131; 

Chris Nye,Alaska Division of Geological 

and Geophysical Surveys–Alaska Volcano 

Observatory, cnye@kiska.giseis.alaska.edu, 

907-474-7430. 

GSA Undergraduate Research Posters. 

Jeff Marshall, Cal Poly–Pomona University, 

marshall@csupomona.edu, 909-869-3461. 

Bering Glacier Symposium - Tectonics, 

Glaciology, Hydrology, Hazards, and 

Biology. Kristine Crossen, University of 

Alaska,Anchorage, afkjc@uaa.alaska.edu, 

907-786-6838. 

Joint: Pacific Section, AAPG, and 

Western Region, SPE 

Arctic Gas Resources. Dave 

Houseknecht, U.S. Geological Survey, 

dhouse@usgs.gov, 703-648-6466; Shirish L. 

Patil, University of Alaska-Fairbanks, 

ffslp@uaf.edu, 907-474-5127 

Viscous Oil: Reservoir Characterization 

and New Technologies. Sandy Phillips, BP 

Expl.Alaska, phillis2@bp.com, 907-564- 

4587; Jeff E. Farr, ExxonMobil Prod. Co., 

jeff.e.farr@exxonmobil.com, 907-564- 

3688; Chris West, BP Expl.Alaska, 

chris.west@bp.com, 907-564-4626 

New Development and Field Case 

Histories. Greg Sanders, Pioneer 

Resources, sandersg@pioneerrc.com, 

Kip Cerveny, BP Expl.Alaska, philip.cerveny@bp.com, 

907-564-5306 

Pacific Section, AAPG 

Petroleum Geology of Northern Alaska. 

Ken Bird, U.S. Geological Survey, 

kbird@usgs.gov, 650-329-4907. 

Rural Energy in Alaska.Travis Hudson, 

ageology@olypen.com, 360-582-1844; 

Charles Barker,U.S. Geological Survey, 

barker@usgs.gov, 303-236-5797 

Schedule continues on page 10


Brookian Reservoirs of the North 

Slope. Ken Helmold,Alaska Division of 

Geological and Geophysical Surveys, 

kph@dnr.state.ak.us, 907-269-8673; Bill 

Morris, ConocoPhillips, william.r.morris@conocophillips.com, 

281-293-4463. 

Reservoir Characterization: Recent 

Advances in Appraisal and Development. 

Steve Jones, BP Expl.Alaska, 

steve.jones@bp.com, 907-564-5831; 

Micaela Weeks, BP Expl.Alaska, 

laryn.smith@bp.com, 907-564-5635 

Alaska Section, SPE 

Western Region, SPE 

For all of these sessions, contact 

Gordon Posposil, BP, pospisg@bp.com, 

907-564-5769 

Rotary and Coiled Tubing Drilling 

Applications 

Well Integrity Management 

Completion Innovations 

Reservoir Characterization and Formation 

Evaluation 

Surface Facility Applications 

Improved Oil Recovery and Reservoir 

Management 

Production Optimization and Artificial 

Lift 

GEMS Sessions (Short Topics) 

Student Papers 

Coffee breaks 

Coffee will be served on the 

Promenade on the second floor between 

the Bristol Bay Ballroom and the Alaska, 

Aleutian, and Denali Rooms during all 

morning and afternoon sessions Monday, 

Tuesday, and Wednesday. 

Anchorage, Alaska 

The Joint Technical Conference is 

being held in Anchorage,Alaska, at the 

Anchorage Hilton Hotel.The city of 

Anchorage is located in a natural setting 

of unparalleled beauty, nestled between 

the wilderness of the Chugach 

Mountains and the two arms of upper 

Cook Inlet. Five mountain ranges and a 

number of active volcanoes can be seen 

from the city.The second highest bore 

tides in North America, numerous glaciers, 

and land submerged by the largest 

earthquake in North America are within 

easy driving distance.Temperatures are 

mild in early May (50°–60° F), with long 

hours of daylight. 

Anchorage is served by several major 

airlines through Ted Stevens International 

Airport, ~5 miles from downtown.The 

meeting site is the Anchorage Hilton 

Hotel in the heart of downtown 

Anchorage.The Hilton is located three 

blocks from the Alaska Railroad station 

and several citywide bus routes. It is 

within easy walking distance of numerous 

restaurants and clubs, downtown 

shops, museums, bookstores, and Cook 

Inlet. 

Please make plans to join us and your 

fellow geoscientists, engineers, and other 

professionals in a truly amazing state that 

boasts the nation’s largest national parks, 

largest oil fields, and glaciers the size of 

other states! 

Spouse and guest activities 

The municipality of Anchorage is 

located as far north as Helsinki, Finland, 

as far west as Honolulu, Hawaii, and covers 

an area nearly the size of the state of 

Delaware. It is the hub of south-central 

Alaska, which offers a wide variety of 

see next page

Page 10 

recreational opportunities from fishing, 

cruising, and bird watching to rock 

climbing, rafting, hiking, and sight seeing. 

Cultural attractions include the Alaska 

Museum of History and Art,Alaska Native 

Heritage Center, Z.J. Loussac Library, 

Alaska Museum of Natural History, the 

Imaginarium science center, and the 

Alaska Aviation Heritage Museum. Most 

attractions are accessible by regularly 

scheduled bus routes as well as taxi. 

Anchorage has over 650 miles of hiking, 

biking, and multi-use trails, many of 

which wind along the city’s greenbelts 

and creeks. 

The Alaska Railroad provides access to 

Prince William Sound at Seward and 

Whittier on the Kenai Peninsula, as well 

as to Denali National Park (home of 

Mount McKinley, the highest point in 

North America),Talkeetna, Fairbanks, and 

other northern destinations. 


Schedule continues 

Field trips 

Field trips have been planned to visit 

a wide variety of Alaska’s spectacular 

geology. Several of these trips are very 

suitable for guests who may not be professional 

geoscientists. 

Linked field trips 

Three of these trips have been scheduled 

such that it is possible to take them 

consecutively, thus linking them together 

to make a traverse from south to north. 

Thus one may travel from the Chugach 

accretionary complex to the Matanuska 

forearc basin, and thence north across 

the Denali fault and the Alaska Range, and 

finish on the Yukon-Tanana basement 

rocks of the interior of Alaska.This is a 

unique opportunity to sample the range 

of fantastic Alaskan geology.A “Surf to 

Turf” tour! 

Kuparuk oil field, 

North Slope Alaska 

Saturday, May 6, no charge to participants, 

compliments of BP Alaska and 

ConocoPhillips 

By drawing for registrants before Feb. 

1 (if interest exceeds plane capacity) or 

until plane capacity is reached after Feb. 

1. 

Plane capacity is 111. Priority in the 

lottery will be given to attendees who 

are registered guests of the Anchorage 

Hilton, since registration at the Hilton 

benefits the Joint Conference. 

The tour will depart Anchorage 

International Airport on Shared Services 

Aviation at 9 a.m.The flight will cross 

both the Alaska Range and the Brooks 

Range before descending on the North 

Slope to the ConocoPhillips-operated 

Kuparuk field. Participants will be given 

an overview of the field geology and 

engineering, a bus tour of the field, a tour 

of the central processing facility, and a 

stop at the Arctic Ocean at Oliktok Point. 

The return flight will depart Kuparuk at 

5 p.m. and arrive Anchorage at 6:40 p.m. 

Lunch will be provided in the Kuparuk 

dining facilities. Participants should 

expect cool to cold weather.Attendees 

will be provided a “North of the Arctic 

Circle” certificate. 

For further information contact 

gregory.c.wilson@conocophillips.com 

Chugach Terrane and Resurrection 

Bay Ophiolite (Linked Trip #1) 

Saturday and Sunday, May 6-7, $245, 

includes van, boat ride, lodging (double 

occupancy), 2 lunches 

Led by Dwight Bradley and Marti Miller 

(USGS).The first day of this two-day trip 

will include a highway traverse across 

the Mesozoic Chugach accretionary complex 

where we will see classic exposures 

of melange, trench turbidites, and small 

near-trench intrusives thought to be related 

to ridge subduction. 

We will spend the first night in 

Seward.The second day will feature a 

boat tour of the scenic Resurrection 

Peninsula ophiolite, an obducted piece of 

Paleocene ocean floor thought to have 

formed along a spreading axis near its 

intersection with the Chugach trench. 

(See “Linked Field Trips”) 


dbradley@usgs.gov 

Anchorage walking tour 

Tuesday, May 9 (evening) $15 (van) 

Led by Peter Haeussler (USGS). See the 

effects of the 1964 Alaskan earthquake, 

and other aspects of Anchorage’s unique 

geology. 


pheuslr@usgs.gov 

Matanuska Valley - Convergent 

Margin Traverse and Forearc Basin 

Stratigraphy (Linked Trip #2) 

Thursday, May 11, $70 includes van, 

lunch, dinner 

Led by Jeff Trop (Bucknell University) 

and Tom Plawman (Anchorage consultant).This 

one-day traverse through the 

Matanuska Valley will emphasize the 

Mesozoic-Cenozoic stratigraphic record 

of synorogenic sedimentation, terrane 

see page 12

North to Alaska: Geoscience, Technology and Natural Resources Page 11

Page 12 


accretion, near-trench magmatism, and 

strike-slip tectonics in a forearc setting. 

A review of recent sedimentologic, 

geochronologic, and geochemical data 

from these outcrops will permit discussion 

of regional linkages with the accretionary 

prism and foreland basin 

deposits. 

For further information contact tplawman@gci.net 

Prince William Sound tidewater 

glacier tour 

Friday, May 12 $155 (bus, boat, lunch) 

Led by Kristine Crossen (University of 

Alaska Anchorage). 

Travel by comfortable bus to see the 

spectacular beauty of Prince William 

Sound’s tidewater glaciers. 

Full-day field excursion from 

Anchorage to Prince William Sound. 

Bus tour down scenic Turnagain Arm 

to Portage Glacier, tunnel passage to 

Whittier, and four hour boat tour in 

Prince William sound to view calving 

tidewater glaciers, seals, and sea otters. 

Travel by comfortable catamaran tour 

boat for a calm ride in sheltered waters. 

This scenic trip is highly recommended 

for both participants and guests.Warm 

clothes recommended. 

For further information contact Kristine 

Crossen afkjc@uaa.alaska.edu 

Denali National Park and Usibelli 

Coal Mine (Linked Trip #3) 

Friday and Saturday May 12-13 $255, 

bus, hotel (double occupancy), two 

lunches 

Led by Phil Brease (National Park 

Service). 

Take a trip along the (antecedent) 

Nenana River where it cuts through the 

mighty Alaska Range near the eastern 

boundary of Denali National Park and 

Preserve, and visit the largest open pit 

coal mine in Alaska. On day one, stops 

along highway 2 will include a major 

Cretaceous suture zone (accretionary closure) 

of south-central Alaska, the Denali 

Fault (not far from the 7.9 epicenter of 

the 2002 earthquake), the K-T Cantwell 

Formation, (within which a dinosaur footprint 

was just found), and the Paleozoic 

Yukon-Tanana basement rocks of the 

interior. 

We will travel within Denali National 

Park along the park road as far as allowable, 

and hopefully capture glimpses of 

caribou, moose and grizzly bear, as well 

as Mt. McKinley itself, weather permitting. 

Overlying it all, of course, are many 

glacial and recent features. On the morning 

of day two, we will tour Usibelli 

Mine, the largest Alaska coal producer, 

and get up close and personal to the late 

Tertiary Usibelli Group, and the always 

exciting, Nenana Gravel 


Phil_Brease@nps.gov 

Short courses 

Alaska’s Volcanoes, Earthquakes, 

and Subduction Zone— Real-Time 

Earthly Data for Classroom Uses 

Sponsored by the National Association 

of Geology Teachers (NAGT). Saturday, 

May 6, 9 a.m. to 4 p.m., Computer 

Laboratory, Carr-Gottstein Academic 

Center, 4104 University Drive,Alaska 

Pacific University. 

Jennifer Adleman, U.S. Geological 

Survey–Alaska Volcano Observatory, jadleman@usgs.gov, 

907-786-7019; Cathy 

Connor, University of Alaska– Southeast, 

cathy.connor@uas.alaska.edu, 907-465- 

6293. Limit: 15. Cost: $75 (includes manual 

and K–12 activi¬ties); an additional 

charge of $75 is required for 1 university 

credit. 

This course will provide participants 

with experience in using web-accessible 

Alaska volcano and earthquake data to 

better understand the subduction-zone 

environment under¬lying south-central 

Alaska. Recent eruptions of Augustine 

Volcano will be of special interest. 

Participants will visit the Alaska Volcano 

Observatory to witness how data is being 

collected by Alaska’s volcanology community. 

Upper elementary, middle school, or 

high school math and science teachers 

who are interested in augmenting their 

earth science knowledge to deliver curricula 

that will meet the new Alaska 

Standards for earth science at the 4th, 

8th, and 10th grade levels should attend. 

In-service teachers can receive university 

credit by enrolling in ED-593 through the 

University Alaska Southeast. 

For further information contact Kathy 

Fagerstrom,Administrative Assistant for 

the UAS Professional Education Center, at 

907-796-6050 or jnkef@uas.alaska.edu. 

For university credit, participants must 

also attend one day of the GSA meetings 

or a GSA field trip and complete a writing 

assignment. 

Application of Ichnology to 

Petroleum Exploration 

and Production 

Sponsored by Pacific Section,AAPG. 

Sunday, May 7, 8:30 a.m. to 4:30 p.m. 

ConocoPhillips Bayview Core Facility, 

619 East Ship Creek Drive,Anchorage (a 

short walk from the Hilton Hotel). James 

MacEachern, Simon Fraser University, 

jmaceach@sfu.ca, +1-604-291-5388; 

Beverly Burns, ConocoPhillips, 

b.burns@conocophillips.com, 907-263- 

4978. Limit: 25. Cost: $150 (includes 

lunch and course manual). 

Ichnology is the study of trace fossils 

(sedimentary structures that directly 

reflect organism activity such as burrows, 

borings, trails, tracks, and fecal pellets), 

bioturbation (sediment mixing and 

disruption of original stratification by 

burrowers), and bioerosion (excavation 

and breakdown of hard substrates by 

boring animals and plants). 

This short course focuses on the sedimentologic 

implications of ichnology, 

especially as they apply to paleoenvironmental 

analysis, emphasizing practical 

applications and conceptual models.The 

course will include an introduction to 

fundamentals (recognition, identification, 

and behavioral interpretation of biogenic 

structures), but will concentrate on application 

of basic principles and new 

advances in ichnology to solving geologic 

problems in shallow marine deposits. 

Ichnological models for the recognition 

and environmental subdivision of strandplain 

shorefaces, deltaic successions, and 

brackish-water environments will be 

included. 

Special attention will be focused on 

the recognition of trace fossils in core, 

with a core workshop component highlighting 

the application of ichnology to 

shallow marine deposits. 

AK Geology Info: Discovering Alaska 

Geologic Data and Information 

Sunday, May 7, 1:30–4:30 p.m., or 

Thursday, May 11, 8:30–11:30 a.m.,Alaska 

Department of Natural Resources 

Computer Training Center, 9th floor, 

Atwood Building, 550 W 7th Avenue, 

Anchorage (four blocks south of Hilton 

Hotel). Larry Freeman,Alaska Division of 

Geological and Geophysical Surveys, 

Larry_Freeman@dnr. state.ak.us, 907-451- 

5027. Limit: 10 each session. No cost to 

participants. 

A hands-on introduction to geologic 

see page 14


Page 14 


data and search engines available 

from the AKGeology.Info 

web site (a product of the federally 

funded Minerals Data 

and Information Rescue in 

Alaska [MDIRA] Program). 

Each session of the course 

will include instructor-led 

tutorials for finding data and 

information ranging from fossil 

localities and geochemical 

data to geological survey 

reports and student theses 

that are specific to Alaska. 

The focus of each session 

will be tailored to the desires 

of the participants.Any geologist 

who regularly uses public 

domain geologic data would 

benefit from attending. 

Well Log Interpretation: 

Principles and 

Applications 

Thursday, May 11, 8:30 a.m. 

to 4:30 p.m., Fireweed Room, 

Anchorage Hilton Hotel. Doug 

Hupp, DHupp@anchorage.oilfield.slb.com 

Schlumberger 

Data and Consulting Services. 

Limit: 40. Cost: US$100 

(includes lunch). 

This course will cover the 

fundamentals of wireline log 

interpretation, including evaluation 

of water, oil, and gas 

saturation, porosity, lithology, 

and estimates of clay volume. 

The course will focus on 

basic measurements such as 

resistivity, gamma ray, neutron 

porosity, formation density, 

and sonic velocity. 

It will finish with a brief 

overview of more advanced 

logging measurements and 

their applications, such as 

nuclear magnetic resonance, 

formation imaging, shear 

sonic measurements, and 

wireline pressure measurements 

and sampling. 

Emphasis will be on the 

basics and will be appropriate 

for a petroleum engineer or 

geoscientist seeking to develop 

basic skills in quantitative 

analysis of logs. 

Logging While Drilling 

(LWD) Interpretation and 

Well Placement 

Friday, May 12, 8:30 a.m. to 

4:30 p.m., Fireweed Room, 

Anchorage Hilton Hotel.Aron 

Kramer, Schlumberger, 

DHupp@anchorage.oilfield.slb. 

com, 907-273-1771. Limit: 40. 

Cost: US$100 (includes lunch). 

This course will cover 

aspects of interpretation of 

measurements using modern 

logging-while-drilling measurements 

in horizontal and highly 

deviated wells. 

The course will assume 

basic knowledge of petrophysics 

and focus on the differences 

between modern LWD 

sensors in horizontal wells and 

more traditional wireline-type 

measurements in vertical wells. 

The course will be particularly 

relevant to geologists and 

geoscientists involved in horizontal 

well drilling. 

Emphasis will be placed on 

techniques, technology, and 

decision making in real time 

that can be used to better 

place horizontal wells for maximum 

productivity. 

Student mentor programs 

Roy J. Shlemon Mentor 

Program in Applied 

Geoscience. Sponsored by GSA 

Foundation. 

Mon.-Tues., May 8-9, 11:30 

a.m. to 1 p.m. Lunch provided; 

location information 

will be available at the meeting 

registration desk. Karlon 

Blythe, GSA, 

kblythe@geosociety.org. 

This is a chance for students 

to discuss career opportunities 

and challenges with professional 

geoscientists from multiple 

disciplines. Plan to attend both 

free luncheons to hear different 

presenters. Students will 

receive FREE LUNCH tickets in 

their registration packet to 

attend the Shlemon Programs. 

However, space is limited: 

first come, first served. 

Student awards 

Awards will be given for 

best student oral (undergraduate 

or graduate) and poster 

(undergraduate only) presentations.To 

be eligible, students 

must be lead authors and presenters, 

and they should clearly 

identify their abstracts as student 

work. For further information, 

contact Dwight 

Bradley, 907-786-7434, 

dbradley@usgs.gov.


Corporate 

Sponsors 

JUDY PATRICK 

ConocoPhillips Alaska 

BP Exploration (Alaska) 

Schlumberger 

WesternGeco 

Shell 

ExxonMobil 

Anadarko Petroleum Corporation 

Chevron Corporation 

Eni Petroleum 

Marathon Oil Company 

Pioneer Natural Resources 

Halliburton 

PGS 

Udelhoven Oilfield Systems Services 

WhiteStar Corporation 

The Joint Technical Conference is being held in Anchorage, Alaska, at the Anchorage Hilton Hotel. The 

city of Anchorage is located in a natural setting of unparalleled beauty, nestled between the wilderness 

of the Chugach Mountains and the two arms of upper Cook Inlet. 

Exhibitor Booths

Page 16 


Opportunities abound 

at upcoming lease sales 

State tracts available in the May North Slope foothills and Cook Inlet basin areawide 

lease sales include underexplored areas 

T 

By ALAN BAILEY 


he state of Alaska’s annual areawide 

lease sales for the North Slope 

foothills and the Cook Inlet basin will 

be held on May 24.And, with both 

regions still substantially underexplored, 

the sales offer tracts with significant petroleum 

potential. Geologist Paul Decker and 

Commercial Analyst Timothy Ryherd of 

Alaska Division of Oil and Gas talked to 

Petroleum News about the petroleum 

geology of the regions. 

The North Slope foothills consist of a 

series of rolling hills, mesas and east-west 

trending ridges that extends north from 

the Brooks Range and merges into the 

southern side of the North Slope of Arctic 

Alaska.The state’s lease sale area lies within 

a 7 million-acre swath of land between 

the southeastern corner of the National 

Petroleum Reserve-Alaska and the western 

side of the Alaska National Wildlife Refuge. 

Within that area, state tracts intermingle 

with inholdings owned by Arctic Slope 

Regional Corp. 

The trans-Alaska pipeline passes north 

to south through the eastern part of the 

region and a future gas pipeline from the 

Prudhoe Bay area is likely to pass along 

that same pipeline corridor. 

Geologically the foothills region straddles 

the fold and thrust belt immediately 

north of the Brooks Range front.The 

region also straddles the axis of the 

Colville Basin, a major forearc basin of 

Tertiary and Quaternary age. 

“You’re right in that transition zone 

from the leading edge of the thrusting, 

overriding the deepest part of the … 

(Colville) basin,” Decker explained. 

The Colville Basin forms a major component 

of the world-class petroleum system 

of northern Alaska. 

Substantial research 

Of five wells drilled in the area only 

one well, the Lisburne Test No.1 drilled by 

USGS in the western part of the area, has 

publicly available data.The data from 

remainder of the wells remain confidential. 

However, geologists have done substantial 

research in the foothills in recent years 

and the results of much of this research 

are available to the public. In particular, a 

team of geologists led by Alaska’s Division 

of Geological and Geophysical Surveys has 

been conducting fieldwork across the 

region.The U.S. Geological Survey has also 

been studying the area. 

Many publications by researchers can 

be found in the DGGS web site at 

http://www.dggs.dnr.state.ak.us/pubs/pub 

s.jsp. Other publications are available in 

professional journals, especially the 

Geological Society of America Abstracts 

with Programs. 

It is well known that most of the major 

source rocks of northern Alaska exist in 

the area. Source rocks include the Triassic 

and Jurassic Otuk formation (in part, equivalent 

to the prolific Shublik formation of 

the central North Slope) and the HRZ/Hue 

shale. In addition, Julie Dumoulin and others 

from USGS have reported a potential 

oolitic and phosphatic source zone with 

total hydrocarbon content of 7 to 8 percent 

within the upper part of the 

Mississippian/Pennsylvanian Lisburne 

group. 

Gas prone 

But, because of the high thermal maturity 

of deeply buried source rocks, geologists 

have long believed the foothills area 

to be gas prone rather than oil prone. 

“I think that most people believe that 

the most likely product that they’d find 

out here would be gas,” Decker said. 

On the other hand source rocks within 

the thermal maturity window for oil are 

found at the surface in some locations, 

especially in the southern part of the area 

near the Brooks Range front.Tectonic 

activity associated with the formation of 

the Brooks Range appears to have pushed 

these source rocks to the surface.And 

dead oil fields are also found in the region. 

“There are a lot of solid hydrocarbon 

occurrences out there … so you know 

there has been oil charge through the 

area,” Decker said.“It’s not out of the question 

that somebody at some point is going 

to find a preserved oil trap.” 

And there is a known oil field at Umiat, 

at the northwestern corner of the lease 

sale area. 

“That’s an obvious positive for oil 

prospectivity,” Ryherd said. 

But the fact that the lower maturity 

source rocks outcrop at the surface raises 

questions about how any generated oil 

would have reached the reservoir rocks at 

depth, Decker thinks. 

Lisburne play 

Much recent exploration interest in the 

foothills has focused on thick limestones 

and dolomites of the Lisburne group.


ALASKA DNR 

South to north section through the North Slope foothills area, showing Paleozoic Lisburne strata thrust over and against Cretaceous rocks of the Colville Basin 

Allochthons of these Paleozoic rocks have 

been thrust faulted north over younger 

strata of the Colville Basin, in the zone of 

compression north of Brooks Range front, 

in the southern sector of the lease sale 

area. In places, the Lisburne has been 

thrust over itself several times. 

Vugs within the dolomites of the 

Lisburne often contain dark asphalt 

residue, indicating the existence of a petroleum 

system.The production of natural gas 

from petroleum in the cavities has probably 

caused asphalt to precipitate at some 

time in the past, Decker explained.And the 

vugs give the dolomite the porosity needed 

to act as a petroleum reservoir. 

“The greatest play interest, explorationwise, 

is for the dolomites,” Decker said. 

The section containing the Lisburne 

dolomites includes shales that could act as 

seal rocks for an oil gas reservoir.And, in 

some places, the Cretaceous shales have 

also been thrust faulted over the top of the 

Lisburne strata. 

“Also there is so little porosity and permeability 

in the non-reservoir parts of the 

Lisburne that it can itself act as a partial 

seal,” Decker said. 

Cretaceous sandstones 

North of the area of intense thrust faulting 

comes an area dominated by 

Cretaceous sandstones and shales of what 

are known as the Fortress Mountain and 

Nanushuk formations, deposited in the 

Colville Basin. 

“As you work your way north the world 

begins change dramatically.You get out of 

the outcrop of Paleozoic rock and into 

Cretaceous rocks,” Decker said. 

The structural style of the area transitions 

north from a thrust zone into a triangle 

zone. 

Explorers in the region tend to focus 

on topset sandstones and turbidites that 

mark deposition across the shelf and into 

the deeper water of the Colville Basin. 

Potential Cretaceous oil or gas reservoirs 

in the rock sequence include coarse sandstone 

and conglomerate eroded from the 

emerging Brooks Range. 

Although the Cretaceous strata have the 

potential to form stratigraphic traps, geologist 

view the majority of the oil and gas 

plays as being structural, associated with 

the extensive faulting and folding in the 

area.The Umiat oil field, for example, 

involves a structural trap in Nanushuk 

see next page

Page 18 


U.S. DEPARTMENT OF ENERGY 

Contour map of the Cook Inlet Basin 

topsets. 

The existence of potential reservoirs 

and source rocks close to the axis of the 

Colville basin has led some geologists to 

postulate the presence of overpressured 

gas deep in the basin. USGS has examined 

evidence of overpressure, using logs from 

wells in the southern part of the North 

Slope, adjacent to the foothills sale area. 

Cook Inlet 

In contrast with the North Slope 

foothills, the Cook Inlet basin has long 

been a producing oil and gas province, but 

lacks the major quantities of publicly available 

geological information that exists for 

northern Alaska. 

“The issue with Cook Inlet in my mind 

is that the exploration that has been done 

has been done by the oil companies is proprietary,” 

Ryherd said. 

In fact DNR is in the process of starting 

a new energy-related research program for 

the Cook Inlet, using a similar approach to 

what the department has been doing in 

northern Alaska for more than a decade, 

Decker said. DGGS has recently hired a 

non-marine sedimentologist to research 

the basin, he said. 

“The basin is in need of some new 

ideas,” Decker said. 

Forearc basin 

However, the general geology of the 

basin is well known.A thick sequence of 

Tertiary non-marine sediments, deposited 

primarily by rivers, has formed in an elongated 

northeast to southwest-aligned forearc 

basin, sandwiched between a subduction 

complex to the southeast and an 

active volcanic arc to the northwest. 

The Tertiary strata of the basin lie over 

an older, predominantly marine sequence 

of Mesozoic rocks that were laid down 

across a wide area of southern Alaska. 

All of the existing oil and gas fields of 

the Cook Inlet occur in Tertiary sandstone 

reservoirs. However, the oil is known to 

have originated from a Jurassic source rock 

in the underlying Mesozoic sequence. 

Almost all of the natural gas is biogenic in 

origin, derived from organic material in the 

Tertiary sediments. 

Most of the existing Cook Inlet oil and 

gas fields were found during exploration 

for oil back in the 1950s and 1960s.And 

although at that time there was little interest 

in finding gas, the discovery of substantial 

volumes of gas in the basin led to the 

development of a Cook Inlet-based gas 

industry. 

However, with gas supplies in the 

region starting to run short and gas prices 

rising, there has been an ever-increasing 

interest in gas exploration around the 

Cook Inlet. Some of the more active plays 

that companies are pursuing now are 

bypass plays, developing gas that was discovered 

but ignored in wells drilled to 

explore for oil, Decker said. 

And a 2004 U.S. Department of Energy 

report suggesting that substantial volumes 

of natural gas remain to be discovered in 

the basin has also encouraged exploration. 

Difficult exploration 

However, exploring the Cook Inlet 

basin can be quite challenging. Fields typically 

contain multiple small reservoirs that 

may be difficult to find.And the alluvial 

deposits and river fans formed in the intermontane 

Tertiary basin are often discontinuous. 

River channels and river fans can be 

difficult to differentiate using single rock 

samples from wells, thus giving rise to 

issues such as knowing how far a particular 

reservoir may extend, Decker said 

“There’s been a lot work over the years 

by the industry to try to predict reservoir 

continuity,” Decker said.


Also, perhaps because of clay content 

of the sediments, it is often difficult to recognize 

pay zones using well logs, Ryherd 

said. It is not always obvious where the gas 

sands are, even if you drill right through 

the middle of a gas reservoir, he said. 

And acquiring high quality seismic in 

the basin is notoriously difficult, in part 

because of the complex structures in the 

basin.The coal seams in the Tertiary 

sequence also tend to absorb seismic energy, 

Decker said. 

Two trends 

Despite the difficulties, oil companies 

have had considerable success over the 

years in located oil and gas fields in the 

basin. But a quick inspection of a map of 

these fields shows that they follow two 

main trends on either side of the basin axis 

— one trend passes up the west side of 

the Kenai Peninsula and the other trend 

passes up the west side of the Cook Inlet. 

Oil and gas leases have also tended to follow 

these trends. 

The trends lie on either side of the central 

axis of the basin. 

“If you look at a map of the well plots 

there’s very few in the core, along the axis 

(of the basin),” Ryherd said. 

Interestingly, the Kitchen oil prospect, 

where Escopeta plans to drill soon from a 

jack-up platform, is on the axis of the 

basin, east of the Middle Ground Shoal and 

Trading Bay fields. 

Decker also commented that much of 

the drilling in the Cook Inlet basin has 

focused on the crests of the major structures 

in the basin. Decker thinks that there 

is scope for exploring the flanks of the 

structures, where fluids will likely have 

migrated up the structures.There is also 

scope to explore for stratigraphic traps. 

“So far the basin has only really been 

explored for structure, not for stratigraphic 

traps,” Decker said. 

Another possible play involves tight gas, 

especially in the southern part of the 

Susitna Valley, at the northeastern end of 

the state’s sale area. 

“Some people talk about tight gas up in 

that area — that is a possibility,” Ryherd 

said. 

Mesozoic possibilities 

The possibility of finding oil and gas in 

the Mesozoic, beneath the Tertiary basin, 

has also intrigued geologists, especially 

since the Cook Inlet oil originated from 

the Mesozoic.And Cretaceous rocks in the 

Mesozoic sequence exposed at either end 

of the Cook Inlet basin show evidence of 

oil formation, Ryherd said. 

However, geologists have also been concerned 

about zeolites clogging the pores 

of potential reservoir rocks — the chemistry 

of the Mesozoic rocks tends to be 

conducive to zeolite formation. 

But Decker thinks that the nature of the 

Mesozoic under the basin is not well 

understood. In fact he hopes that the 

Mesozoic oil and gas potential will become 

one focus of the new DNR Cook Inlet 

research program.The program might 

establish better knowledge of how and 

when the zeolites might have formed, 

compared with the timing of oil and gas 

generation and migration, he said. 

“Those are just some of the ideas we’ve 

talked about internally here … between 

ourselves and DGGS,” Decker said. 

And high oil and gas prices are creating 

considerable interest in the Cook Inlet. 

Participation in the past few sales has been 

very high, some new companies have 

recently bought into the area and there is 

talk of more companies coming to 

explore, Decker said. 

High oil and gas prices have also been 

encouraging a surge of drilling in the Cook 

Inlet basin, Ryherd said. 

“If you’re looking at it from the explorer’s 

perspective it’s good times, I think,” he 

said.

Page 20 


Undiscovered riches in Beaufort, 

Chukchi seas 

Structures larger than Prudhoe Bay exist in regions that extend the prolific onshore petroleum 

systems of northern Alaska 

W 



ith Shell planning to restart drilling 

in the Beaufort Sea and seismic 

surveys planned for both the 

Beaufort Sea and the Chukchi Sea, 

this may be a good time to review the 

petroleum resource potential of the outer 

continental shelf of northern Alaska.And at 

the April 6 meeting of the Geophysical 

Society of Alaska U.S. Minerals Management 

Service geologist Kirk Sherwood spoke 

about the new MMS assessment of Alaska’s 

Arctic offshore region. 

Sherwood said that MMS divides most of 

that region into two large areas, the 

Beaufort Sea and Chukchi Sea planning 

areas.The new MMS assessment has estimated 

a total of 104 trillion cubic feet of undiscovered 

technically recoverable natural gas 

and 23.6 billion barrels of undiscovered 

technically recoverable oil in these two 

areas combined.That represents about 79 

percent of the gas and 89 percent of the oil 

in all of the outer continental shelf of 

Alaska, Sherwood said. 

“We consider the Arctic offshore a pretty 

rich province,”he said. 

But why does the MMS consider the 

region to be so well endowed with petroleum 

resources 

A prime reason, Sherwood said, is that 

the geology of both the Chukchi and the 

Beaufort outer continental shelves shares 

much in common with that of the highly 

successful onshore petroleum province of 

northern Alaska. 

Three stratigraphic sequences 

Sherwood described the three major 

stratigraphic sequences that characterize 

the onshore geology of northern Alaska and 

which underpin the world-class petroleum 

system there. 

“All of these (sequences) extend in some 

form directly offshore into the Beaufort and 

Chukchi Sea planning areas,”Sherwood 

said. 

The first of the sequences, known as the 

Ellesmerian, involves rocks deposited southwards 

from an ancient landmass to the 

north of what is now the Beaufort Sea 

A plot of Arctic Alaska offshore prospect sizes, showing the existence of some very large prospects 

coast, from late Devonian through Triassic 

times.The Ellesmerian sequence includes 

the reservoirs for the Prudhoe Bay, Lisburne 

and Endicott fields. Sediments of the 

Ellesmerian sequence accumulated in a 

basin termed the Arctic Alaska basin that 

extends east to west under what is now the 

southern North Slope and Brooks Range 

Foothills. But the Arctic Alaska basin also 

extends west under the Chukchi Sea, where 

it veers northwest into what is known as 

the Hanna Trough. 

The next sequence, known as the 

Beaufortian or rift sequence, resulted from 

the breaking apart or rifting of the Canada 

basin of the Arctic Ocean in Jurassic and 

early Cretaceous times.The rifting resulted 

in the formation of fault blocks, with sagging 

blocks between higher blocks. 

Deposition of sand into the sags gave rise to 

reservoir quality sandstones.The Kuparuk 

River,Alpine, and Milne Point fields, among 

others, involve Beaufortian reservoirs. 

Beaufortian sags, potentially containing 

petroleum reservoirs, extend along the 

Beaufort Sea shelf north of the shoreline 

and across a wide area of the northern 

Chukchi Sea. For example, the huge Burger 

gas reservoir, discovered in the Chukchi 

Sea, is in a Beaufortian rift shoulder sag, 

Sherwood thinks (see “Burger delivers”in 

the Feb. 13 2005 edition of Petroleum 

News). 

The rift sequence is also associated with 

the formation of the Barrow Arch, a major 

structural high that extends along the 

Beaufort Sea coast and that guided the 

migration of petroleum to major oil fields 

such as Prudhoe Bay. Sherwood said that 

the Barrow Arch extends west under the 

Chukchi Sea, where it bifurcates into two 

arches. One of these arches extends northwest, 

before veering to the southwest.The 

other arch veers southwest immediately, to 

pass near the center of the U.S. sector of 

the Chukchi. 

The third major sequence, known as the 

Brookian sequence, formed in Cretaceous 

and Tertiary times as a result of the emergence 

of the Brooks Range.The emerging 

mountain range caused sediments to flow 

into a huge basin, known as the Colville 

basin, under what is now the North Slope. 

That basin extends west under the


Chukchi. Brookian sediments also spilled 

out over the Beaufort Sea continental shelf 

into what are known as the Nuwuk and 

Kaktovik basins, and into the North 

Chukchi basin in the northern part of the 

Chukchi Sea. 

Fields such as Meltwater,Tarn and West 

Sak are associated with the Brookian 

sequence. 

Many structures 

A second reason to view the Arctic offshore 

region as well endowed with petroleum 

resources is the abundance of fold and 

fault structures that could trap oil and gas. 

“The offshore area is full of very complex 

structures that create numerous potential 

traps,”Sherwood said. 

Sherwood showed examples of subsurface 

folds and faults depicted in seismic 

lines that have been shot offshore. 

“Any seismic line you pick out there is 

full of all kinds of structures and, therefore, 

we have a lot of prospects,”he said.“… Our 

current inventory of mapped prospects for 

the Beaufort and Chukchi Sea planning 

areas is about 1,100.” 

For example, a series of major faults slice 

through the thick Brookian sequence along 

the “hinge line”that marks the zone where 

the Beaufort Sea continental shelf slopes 

north into the Arctic Ocean. 

These are “Gulf Coast-style structures, 

very few of which have ever been tested,” 

Sherwood said. 

And what makes the region particularly 

intriguing is the size of some of the structures 

— more than 12 of the identified 

structures exceed 150,000 acres in extent, 

thus exceeding the size of either the 

Prudhoe Bay or Kuparuk River fields.There 

A map of the Brookian basins of northern Alaska, showing the geological continuity between onshore 

and offshore regions 

are 24 identified prospects more than 

100,000 acres in size and 95 more than 

40,000 acres, the approximate size of the 

Alpine field. 

“There ought to be a fair number of 

large opportunities out there and we think 

some may be big enough that they could be 

economic,”Sherwood said. 

Estimating the resources 

Sherwood went on to overview how the 

MMS scientists use the geological information 

from offshore wells and seismic data to 

estimate volumes of technically recoverable 

resources, and then estimate how much of 

these resources might be economically 

recoverable. 

The first step of the process, Sherwood 

explained, is to establish families of oil and 

gas prospects that are called plays. 

Prospects grouped within plays share characteristic 

features such as the reservoir 

stratigraphic sequence, petroleum charge 

and structural setting. 

The thermal maturity of the reservoir 

rocks in an area can also be used to distinguish 

plays. For example, Ellesmerian reservoir 

rocks tend to transition from thermal 

maturities permissive for survival of oil in 

the northern part of the Chukchi to areas in 

the south where the high thermal maturity 

of reservoirs precludes survival of liquid 

petroleum — Ellesmerian reservoirs in the 

latter area were assessed as charged only by 

gas. 

MMS has identified a total of 39 plays, 

see next page

Page 22 


including 24 Brookian plays, in the Beaufort 

and Chukchi seas planning areas, Sherwood 

said.Then, within each play, geologists use 

seismic sections to develop an inventory of 

identified, mapped and sized prospects. It is 

then necessary to estimate the number and 

sizes of prospects that have not been identified, 

perhaps through lack of seismic coverage. 

“We can never say that we know where 

all the prospects are,”Sherwood said. 

One technique for doing this estimation 

in a region of sparse seismic data is to calculate 

the density of mapped prospects in 

areas that do have seismic coverage and 

apply that density across the entire region. 

The total of mapped prospects and the 

total of mapped plus estimated prospects 

then become two ends of a statistical distribution 

that describes the possible numbers 

of prospects within a particular play. But 

then it is necessary to allow for the fact that 

not all prospects will contain hydrocarbon 

pools (i.e. hydrocarbons in sufficient quantity 

to flow to a well bore).That is done by 

estimating the probability of exploration 

success both for each individual prospect 

and for a play as a whole — each prospect 

can be modeled using whatever information 

about the geology is available. 

Then a statistical model runs through 

10,000 different combinations of estimated 

pool parameters to crank out tens of thousands 

to hundreds of thousands of possible 

petroleum pools.These potential or “simulation”pools 

can then be used to calculate 

statistics for probable pools within each 

play.This statistical analysis typically results 

in an average of about a couple of dozen 

predicted pools for each play, Sherwood 

said. 

Economic assessment 

But, although this type of analysis predicts 

large volumes of technically recoverable 

resources in the Beaufort and Chukchi 

seas planning areas, how much of this 

resource might viably be recovered The 

remoteness, sea ice and harsh climate of the 

Beaufort and Chukchi have tended to limit 

interest in oil and gas exploration in these 

regions. 

For an economic assessment the MMS 

commercial analysts modeled the type of 

infrastructure needed to develop the offshore 

resources.The assumed infrastructure 

included offshore platforms, subsea 

pipelines and onshore pipelines connecting 

to the existing pipeline infrastructure.The 

assessment also assumed the existence of a 

gas export pipeline from the North Slope. 

For each of the simulation hydrocarbon 

pools developed by the geologists the analysts 

applied an engineering simulation and, 

thus, estimated a cost and revenue scheme 

that was processed through a discounted 

cash flow model. Further statistical analysis 

of all the simulation pools then produced 

plots of economically recoverable resources 

across ranges of potential oil and gas prices. 

The result: resources in the Beaufort Sea 

planning area start to become economically 

recoverable at about $22 per barrel for oil 

and $3.33 per thousand cubic feet for natural 

gas, Sherwood said. But significant economically 

recoverable volumes of oil do not 

start to appear until price levels of between 

$40 and $50 per barrel are attained.A pricesupply 

curve for gas appeared to indicate 

the need for prices in the range of $6 to $8 

per thousand cubic feet for significant 

recoverable volumes of gas. Price thresholds 

for the Chukchi are about one-third higher, 


So, what does all that mean in terms of 

the potential future development of these 

remote regions Alaska North Slope crude 

has been trading at between $55 and $65 

for the last six months, Sherwood said. 

“If you think that’s the way it’s going to 

continue into the future, you can see that 

there are substantial quantities of oil and 

gas that could be economically recoverable 

from the Beaufort Sea,”he said.And at current 

prices there are also substantial recoverable 

volumes under the Chukchi.


Gil Mull: A modern-day rock sleuth 

Petroleum geologist recounts 40 years working in the field in northern Alaska 

T 

By ROSE RAGSDALE 

For Petroleum News 

he first thing that Charles G.“Gil” 

Mull will tell you about his many 

contributions to solving the subterranean 

mysteries of Alaska’s oil 

patch is that he is one of a long line of 

geologists who together made today’s 

body of knowledge possible. 

Yet Mull’s accomplishments are legend 

in the 49th state’s petroleum history. 

Why Like the fictional Forrest Gump, 

Mull witnessed or played a role in many 

of the most exciting oil-related events in 

Alaska in modern times. He was one of a 

handful of well geologists on the scene 

when Prudhoe Bay, the largest oil field in 

North America, was discovered in the 

late 1960s. He also tramped across the 

North Slope, from the Canadian border 

to Point Hope, gleaning an intimate 

understanding of the geology of the 

region and the oil prospectivity of the 

Arctic National Wildlife Refuge and the 

National Petroleum Reserve-Alaska. 

Mull’s acquisition of information 

about Alaska rocks didn’t stop there. He 

also clambered over the slopes of the 

Brooks Mountain Range as far west as 

the Chukchi Sea and traversed the 

inclines of the Wrangell-St. Elias 

Mountains in search of clues to the geology 

of the Gulf of Alaska. 

The American Association of 

Petroleum Geologists is also honoring 

Mull at its annual western conference in 

Anchorage in May 2006. 

Now living in Santa Fe, N.M., the 70- 

year-old Mull retired in 2003 after working 

41 years in Alaska.Along the way, he 

distinguished himself in the oil industry 

in a way that few petroleum geologists 

have in modern times. His uncommon 

commitment to geology field work sets 

him apart in an era when computers, 

remote sensing and increasingly sophisticated 

laboratory tools dominate the profession. 

The Making of a Petroleum 

Geologist 

How did Mull, an unassuming guy 

with a broad handsome face and quirky 

sense of humor come to explore the geological 

wilderness of Alaska and before 

that, develop a fascination for petroleum 

geology 

It all began in childhood, says Mull, 

who was born in Illinois and grew up in 

West Texas and oil shale country in western 

Colorado. Mull’s father worked as a 

chemical engineer in the oil industry. 

“My family spent a lot of time in old 

mining camps and ghost towns, playing 

tourist, picking up crystals, rocks and lots 

of sparkly things,” Mull recalls. 

In junior high and during his early 

high school years, Mull’s lifelong love 

affair with rocks began to gel. 

“Dad made a little cabinet with drawers 

and partitions, and I started a mineral 

collection,” he said.“I became sort of a 

mountain person, and spent a lot of time 

in the wilderness, climbing and skiing in 

winter. Geology was sort of natural. I also 

spent time in the canyons of eastern 

Utah and there, the geology is really 

exposed. It’s all out there. 

“Before that we lived in West Texas 

downwind of a refinery, and to this day, 

hydrogen sulfide doesn’t smell too bad,” 

he added, with a chuckle. 

After high school, Mull said he “spent 

eight happy years being a ski bum” in 

western Colorado while he attended college 

and graduate school at the 

University of Colorado Boulder. 

Mull initially pursued mining geology, 

but discovered that petroleum geology 

was more interesting, though “it didn’t 

have the bright sparklies.” 

With only a thesis left to complete, 

Mull left school in 1960 to take a job, 

working in what is now Canyonlands 

National Park in southern Utah for 

Richfield Oil Co. 

Before that, Mull had performed field 

work for Richfield during several summers 

in Utah, Colorado and western 

see next page 

ALAN BAILEY

Page 24 

Wyoming. His first year with Richfield, in 

fact, was 1957, the year of the Swanson 

River oil field discovery near Cook Inlet, 


Intrigued by the historic oil find, Mull 

became interested in someday exploring 


For the next two summers, the young 

geologist asked to work in Alaska but was 

told by Richfield that he was needed in 

the same tri-state region. 

“Life was good,” he recalled, referring 

not only to the job but also his bachelor 

status and the abundant outdoor recreation 

opportunities in the Salt Lake City 

area. 

In March 1961, Mull got a call from 

former boss, Harry Jamison, offering him 

a job in Alaska. Mull immediately committed 

to two years of field work in Alaska. 

“I had known Gil since he got out of 

school. I was in charge of a field party in 

southwest Utah in 1960. I was the senior 

member and he was the junior member 

of the team, so I picked him to be my 

field partner for the summer. I got to 

know Gil very well,” Jamison recalled. 

“Then I was put in charge of 

Richfield’s program in Alaska.The first 

opening I had, I called Gil and asked him 

to join me. I knew he was a solid geologist 

and an excellent field geologist. I also 

knew he was young and single,” said 

Jamison, who also is retired and living in 

Tucson,Ariz. 

“That was the beginning of his long 

and very successful career in Alaska. He’s 

often told me, it was my fault he ended 

up in Alaska,” Jamison chuckled. 

Mull and Jamison are still good 

friends. Nowadays, the two geologists get 

together to seek new adventures for two 

weeks of camping and field exploration 

every summer in the Southwest. 

Helicopter Rock Hound 

When Mull got to Alaska, his first 

assignment was to explore Cape 

Yakataga,“sitting on oil wells in the Gulf 

of Alaska.” In 1962, he joined a team 

exploring the region bordering the 


Mull was one of a handful of well geologists on the scene when Prudhoe Bay, the largest oil field in 

North America, was discovered in the late 1960s. 

Yukon River from Circle to Eagle with 

another geologist.After hauling in fuel by 

riverboat, they worked their way through 

the Interior, camping along the Yukon at 

night and exploring valleys on both sides 

of the river by day. 

“We were doing basic mapping in 

areas thought to have potential,” Mull 

said.“We would look for signs of oil, 

source rocks, seeps, porous rocks and 

organic shales, paying attention to the 

potential of the geologic formations.We 

would keep these things in the back of 

our minds, while mapping what’s there. 

For a field geologist, this was paradise.” 

Soon afterward, Mull was assigned to 

explore the North Slope, starting at 

Umiat and working northward to what is 

now the Prudhoe Bay area. Far from 

COURTESY GIL MULL


being alone in a vast wilderness, Mull 

worked with partners and he often 

encountered geology teams working for 

competing companies.At Richfield, Mull 

initially partnered with Gar Pessel, later 

with Howard Sonneman at Exxon Oil Co. 

and then Ellie Harris at the State of 


It was a busy time. Some 10-12 oil 

companies sent field parties all over the 

Slope for three or four years in the mid- 

1960s in a highly secretive and competitive 

process, Mull said. 

“It was a hell of deal! We got our own 

float/ski plane and helicopter and were 

given a mandate to go mapping,” he said. 

“You could work several careers as a 

geologist and never get that kind of 

opportunity.” 

A few years later, when the Prudhoe 

Bay giant was discovered Dec. 26, 1967, 

Mull was one of several well geologists 

on the project.This time, he represented 

Humble Oil, which had partnered with 

Richfield to explore the area. 

Soon afterward, Humble merged with 

Exxon Oil Co., while Richfield joined 

with Atlantic Oil Co. to become ARCO. 

“There is no question that I was lucky 

to be in the right place at the right time,” 

opined Mull.“It was no genius on my 

part to be one of the well geologists on 

the Prudhoe Bay discovery. It was pretty 

exciting, and not a bad Christmas present.” 

Mull recalled that day in the oil history, 

Crude Dreams:“The gas readings on 

the mudlogger had gone off the scale. It 

was pretty obvious that we probably had 

COURTESY GIL MULL 

a gas well.” 

Today, he recalls the sound of the gas 

coming out of the well as being like a 

737 jet roaring overhead. 

“A lot of petroleum geologists spend a 

whole career and never see anything like 

that,” he said. 

The gas flare on Prudhoe Bay State 

No. 1 burned for more than 24 hours 

before the rig crew could resume 

drilling. 

Drillers encountered the Prudhoe Bay 

formation at 8,200 feet, dipping slightly 

to the south, and the partners chose to 

drill a confirmation well seven miles 

away where they encountered the 

Prudhoe Bay reservoir at 8,600 feet, Mull 

said. 

“With a 400-foot interval, we suspected 

we had something big,” he said.“But 

none of us in our wildest imaginations 

dreamed of finding something as big as 

the oil accumulations up there.The 

North Slope has the largest oil field in 

North America, and it supplied 25 percent 

of oil production in the United 

States.” 

Technical advances made by the oil 

industry during the past 30 years also 

were beyond the imaginings of early 

see next page

Page 26 


explorers, Mull said.“One well can be 

drilled six-seven miles in a circle.You can 

find a billion barrels of oil in an area that 

size and produce all of it with that one 

well.” 

When Mull’s wife,Yvonne, heard that 

the 550-million-barrel Alpine oil field was 

being developed on 100 acres, Mull said 

she observed that the oil field would be 

smaller than the family farm where she 

grew up.“I don’t think we realize how 

small 100 acres really is,” he added. 

Helicopter mapping thrilled Mull.“We 

started off doing some of the same things 

that were done in the Lower 48 100 

years ago,” he said.“It was challenging to 

try to dope out the geology, to put it 

together in a coherent picture.” 

Most of the projects were done by 

teams, which he says explains much of 

his success.“You have somebody else to 

bounce ideas back and forth. It’s sort of 

confidence building when you have 

somebody to agree or disagree,” he said. 

“It would be pretty tough to do the work 

alone in vacuum.There’s an expression: 

‘You can see what you believe.’You need 

somebody else to keep you on an even 

keel.” 

The Call of the Wild 

The discovery of Prudhoe Bay became 

an important professional crossroads for 

Mull. 

“I’m sort of an explorationist at heart,” 

says the geologist, who whimsically closes 

all of his emails with a John McPhee 

quote. 

“Geologists inhabit scenes that no one 

ever saw, scenes of global sweep, gone 

and gone again, including seas, mountains, 

rivers, forests, and archipelagos of 

aching beauty, rising in volcanic violence 

to settle down quietly and forever disappear 

— almost disappear,” McPhee wrote 

in “Annals of the Former World.” 

This poetic observation sums up 

Mull’s view of being a field geologist. 

“I could have gone on with Prudhoe 

Bay as a production geologist, and it 

would have been much more financially 

rewarding. 

Instead, Mull chose to return to the 

field, mapping the vast reaches of Alaska 

by helicopter during summer and analyzing 

data collected over the long Alaska 

winters. 

Did discovery of Prudhoe Bay influence 

the path of Mull’s career Yes, definitely. 

“After that, anything we wanted to do, 

there was no problem,” he recalled. 

“Prudhoe Bay made it a lot easier to do 

things. No way could we get the money 

today to do the things we did back then.” 

Still, trouble was brewing in paradise 

for Mull. 

“I began to see the handwriting on 

the wall by 1975,” Mull said.“At Exxon, a 

number of field projects were proposed 

for all of Alaska. One that I proposed was 

to explore the Chugach/Wrangell-St. Elias 

mountain ranges.” 

Specifically, Mull suggested exploring 

the high slopes of Bagley Ice Field on the 

premise that more mapping was needed 

to understand the geology of the Gulf of 


In a department planning meeting at 

Exxon, the proposed field trip came up 

for discussion and Mull’s bosses asked 

the geology team for volunteers to take 

the assignment. 

Only Mull raised his hand. 

One his managers laughed, Mull 

recalled.“Damn Mull!” he said.“You’re 

going to have to settle down to a desk 

job one of these days and learn how to 

be an oil geologist.” 

“At that point I knew it was just a matter 

of time,” Mull said.“I was willing to do 

many things for Exxon. But flying a desk 

full time out of Houston,Texas, was not 

one of them.” 

When the opportunity arose shortly 

afterward to do pure field work for the


U.S. Geological Survey, Mull 

changed jobs. In 1981, he 

moved again to the Alaska 

Division of Geological and 

Geophysical Surveys, Division 

of Oil & Gas where he served 

as senior petroleum geologist 

until he retired in 2003. 

Ups and Downs 

of Field Work 

Mull’s projects at USGS 

included geological mapping 

of the 19 million acre Arctic 

National Wildlife Refuge at the 

behest of the U.S. Fish & 

Wildlife Service some 20 

years ago. 

“We were asked to outline 

interest in ANWR geology and 

the oil and gas potential of 

the coastal plain,” Mull said. 

“We found there is absolutely 

no oil potential in the mountains 

of ANWR, but there is 

significant potential along the 

coastline.” 

After the oil embargo of 

the 1970s, another project 

arose when Congress transferred 

oversight of the Naval 

Petroleum Reserve 4 (PET-4) 

to the U.S. Department of 

Interior. USGS, a part of 

Interior, renamed the 23 million 

acre expanse the National 

Petroleum Reserve-Alaska. 

Mull recalled the frustrations 

of his early work in the 

NPR-A. 

“The contractors (out of 

Texas) who were mapping 

the NPR-A didn’t know beans 

about the North Slope.We 

were to advise them,” he said. 

“They took our advice sometimes 

and sometimes not.” 

Common misunderstandings 

also cloud the layman’s 

view of geological work. 

“The number one misconception 

people have is that 

you can get it all out of 

books,” Mull said. 

“Number two is if geologists 

look in a certain area, 

they must be looking for 

something.” 

On the contrary, geologists 

typically look for signs or 

clues, he said.They try to pick 

up a variety of clues over a 

The Umiat well 

vast area to solve a mystery 

about a region. In other 

words, geologists collect a lot 

of little things to grasp the 

key to unlocking a puzzle in 

the big picture, Mull 

explained. 

“When dealing with the 

geological world, it is part art 

and part science, putting 

things together with different 

mental extrapolations, correlations 

and interpretations,” he 

said. 

Another point of confusion 

for many people is that a 5 

percent chance of finding 

something in mineral or oil 

exploration sounds like really 

poor odds, but is actually a 

phenomenally high chance of 

success, Mull said. 

“What drives oil and gas 

drilling is the low probability 

end of the curve where you 

can make a significant discovery,” 

he said. 

Oftentimes, geological findings 

become entangled in 

political interests. 

“Science would say one 

thing, and politics will say 

another,” Mull said. 

For example, one politician, 

Cecil D.Andrus, set out 

to obscure the facts about 

USGS’ economic and geological 

assessment of the respective 

oil and gas potential of 

ANWR in comparison to NPR- 

A in 1980.Andrus, who served 

as Secretary of the Interior 

under President Carter, wanted 

to restrict oil and gas 

exploration in all of ANWR, 


Mull said. 

USGS concluded that the 

NPR-A had roughly the same 

oil and gas potential as 

ANWR, but sharply different 

economic potential.The difference, 

said Mull, is that NPR- 

A is 10 times bigger that the 

area of ANWR where oil is 

believed to be pooled in significant 

quantities. 

“He tried to squash that 

information,” he said.“We said 

if you’ve got 5 billion barrels 

of oil in teacup-size accumulations, 

that area will be far less 

economical to develop than 

an area where the same 5 billion 

barrels has collected in 

several large pools. (Andrus) 

obscured and twisted the 

thing. But that’s just politics.” 

Another source of frustration 

emerged later when he 

worked for the State of Alaska 

during the oil crunch years of 

the late 1980s and more 

recently during the Tony 

Knowles administration, Mull 

said. 

“My biggest disappointment 

was dealing with state 

administrators who couldn’t 

care less what we were doing 

northern Alaska,” he said.“We 

could have accomplished a lot 

more with some institutional 

support from them.We had 

myopic managers and we 

wasted a lot of time fighting 

battles that didn’t need to be 

fought.” 

Fortunately, the oil industry 

recognized the importance of 

the work being done by the 

state’s geologists in northern 

see next page

Page 28 

Alaska and offered its support, Mull said. 

“It was a world of change when Ken 

Boyd and Mark Myers came in as directors 

of the Division of Oil & Gas and 

when Tom Irwin became Commissioner 

of Natural Resources,” Mull said. 



Making a Difference 

Of the considerable accomplishments 

of his career, Mull said he is most proud 

of the discovery that the entire northern 

central part of the Brooks Mountain is at 

least 100 miles out of place. Geologically 

speaking, this area should be further 

south near Wiseman. 

It was Mull who put together geological 

clues to prove that shifting of continental 

plates pushed chunks of the 

upper crust of the earth northward.Thus, 

the sequence of rocks far south of the 

North Slope around Mount Doonerak in 

the Gates of the Arctic National Park is 

identical to the subsurface of ANWR and 

Prudhoe Bay. 

“It proved this whole mountain range 

has been pushed northward in a thrust 

fault,” Mull said.“It showed tremendous 

geological insight. It was an exciting 

technical discovery, but there are still 

people who don’t believe it. But I call it 

elegant proof.” 

The intrepid Mull’s wanderings also 

enabled him to identify several important 

archeological sites in the Brooks Range at 

Tukuto Lake and Anaktuvuk Pass, locations 

that have enabled scientists to identify 

new types of chert and to plot trade 

routes and solve other mysteries of the 

prehistoric residents of the region. 

Mull, of course, is quick to point out 

that the breakups he made in conquering 

the geological frontier of northern Alaska 

probably would not have happened without 

his fortuitous and frequent interaction 

with many knowledgeable colleagues. 

“I worked with a lot of other people 

who know as much about the geology of 

northern Alaska as I do,” he said.“The difference 

is I survived,” Mull said.“And a lot 

of people have more detailed knowledge, 

but I was able to cover more area, from 

the Canadian border to Point Hope.” 

Among other talented geologists who 

worked in Alaska, Mull specifically cites 

USGS’ Ken Bird,Tom Moore, Dave 

Houseknecht as well as an earlier generation 

of explorers, including Dietrick 

Roeder, Irv Collier and Bill Brosge. 

“I met Dietrich Roeder in 1968 not 

long after I started with Exxon. He was 

very influential in my understanding of 

The Prudhoe Bay State No. 1 well. 

the Brooks Range. He essentially brought 

me up to date with plate tectonic concepts 

(continental drift), which were 

being developed in the geosciences 

world in the 1960s. But being in remote 

Alaska during that time, I had little familiarity 

with this major revolution in geologic 

concepts until I met Dietrich. Some 

of the new concepts immediately 

explained some of the enigmatic geologic 

relationships we had been seeing in 

the Brooks Range, and certainly influenced 

how I interpreted things we were 

seeing after that time,” Mull said. 

The superb work of helicopter pilots 

and support crews, including camp 

cooks, also played a critical role in Mull’s 

success. 

“Without their outstanding contributions, 

I would not be here today,” he said. 

“You remember those old helicopters. It 

was like flying in a glass fish bowl held 

together with baling wire,” he quipped. 

The veteran geologist points with 

pride to the many young geologists he 

has enticed into the field in Alaska. 

“Grad students today are getting just a 

tiny piece and never get to look at the 

broad picture. It’s not like being on that 

cliff face and looking at the sandstone or 

limestone.That’s why geologists take 

field trips,” he said.“It is sometimes tough 

to do when you are being assigned to 

specific projects.” 

There was a period, however, when 

such geology field trips were restricted 

by federal officials, said Mull. 

“I believe that is contrary to why 

national parks were established,” he said, 

noting that recently, the restrictions 

appeared to be easing. 

Mull’s one piece of advice for young 

geologists:“See absolutely as many rocks 

as you can. Don’t get bogged down in 

one place. Keep it regional if you can.” 

Why Geological concepts are constantly 

evolving, he said. 

Plate tectonics, for example, has 

changed how geologists look at mountains. 

“New concepts are coming along on 

meteor impacts and catastrophic extinction,” 

Mull explained.“There are locations 

in the western Brooks Range and the 

DeLong Mountains where I would love 

to go back to and think about those concepts. 

“That’s part of the reason geologists 

keep going back to the same localities 

over and over again, to look at things 

with a new eye,” he added. 

An interview of Gil Mull conducted 

Karen Brewster for Project Jukebox, an 

oral history compiled by the University 

of Alaska Fairbanks, contributed to this 

article.


New assessment 

released for 

Alaska OCS 

Results from new model are similar 

in overall estimated resources 

I 



n support of planning for 

its 2007 to 2012 leasing 

program, the Minerals 

Management Service has 

reassessed the petroleum 

resources in all 15 planning 

areas in the Alaska outer continental 

shelf.The agency last 

assessed all of the planning 

areas in 1995, although it did 

reassess the higher potential 

areas in 2000. 

In most instances the oil 

and gas plays that MMS uses 

for its assessments have not 

Alaska sales set May 24 

T 

By KRISTEN NELSON 


he State of Alaska’s 2006 

Cook Inlet and North 

Slope Foothills areawide 

oil and gas lease sales will 

be held May 24 in Anchorage. 

The Alaska Department of 

Natural Resources’ Division of 

Oil and Gas said bid opening 

will begin at 8:30 a.m. at the 

Wilda Marston Theater in the 

Loussac Public Library. 

The 815 Cook Inlet tracts 

range in size from 640 to 5,760 

acres and will be offered for a 

minimum bid of $10 per acre 

and a fixed royalty rate of 12.5 

percent. 

This year the tracts have two 

different lease terms, with one 

group of tracts being offered for 

seven years and the other group 

for five years, a change from 

previous Cook Inlet areawide 

lease sale terms, Division of Oil 

and Gas Deputy Director Pirtle 

changed significantly, MMS 

supervisory geologist Larry 

Cooke and MMS geologist 

Kirk Sherwood told 

Petroleum News. So, although 

MMS has refined its assessment 

models, the estimates of 

technically recoverable 

resources — resources that 

could be extracted, regardless 

of cost, using known technologies 

— remain broadly 

similar to those in previous 

assessments. 

“Just looking at the overall 

bottom line, it didn’t change 

that much for the conventionsee 

next page 

Bates told Petroleum News. 

The shorter term leases will 

be for tracts that are generally 

within three miles of existing 

infrastructure and/or the shoreline. 

There are 1,347 tracts in 

the North Slope Foothills sale, 

ranging in size from 1,280 to 

5,760 acres.All tracts in the 

Foothills sale have a minimum 

bid of $5 per acre, a fixed royalty 

rate of 12.5 percent and a 

term of 10 years.This sale has 

no new terms. 

In 2004 and 2005 Cook Inlet 

areawide sales the state leased 

225,000 to 250,000 acres and 

drew total bids in the range of 

$1.5 million to $1.7 million. 

In 2004 and 2005 Foothills 

sales the state leased from 

20,000 to 55,000 acres and 

drew total bids of some 

$106,000 to $320,000. 

More information is available 

on the division’s Web site at 

www.dog.dnr.state.ak.us/oil/.

Page 30 


COURTESY MMS 

2006 Alaska OCS planning areas and assessment provinces 

ally recoverable (resources) in Alaska,” 

Cooke said.“We were up, on average, 

about 7 percent.” 

For example, since the 2000 assessment 

the mean estimate for technically 

recoverable oil from the Beaufort Sea has 

increased from 6.94 billion barrels to 

8.22 billion barrels, while the corresponding 

mean estimates for natural gas 

have dropped from 32.07 trillion cubic 

feet to 27.65 tcf. For the Chukchi Sea, the 

mean estimate for oil has changed from 

15.46 billion barrels to 15.38 billion barrels.The 

mean estimate for Chukchi natural 

gas has gone from 60.11 tcf to 76.77 

tcf. 

As well as calculating estimated mean 

volumes, MMS estimates possible ranges 

in resource volume.These ranges have 

increased significantly in the latest assessment, 

suggesting a higher level of uncertainty 

in the estimates than previously 

calculated. 

The potential range in estimated technically 

recoverable oil for the Beaufort 

Sea has gone from between 3.56 billion 

barrels and 11.84 billion barrels to a 

range of between 0.41 billion barrels and 

23.24 billion barrels. For natural gas, the 

range has gone from between 12.86 tcf 

and 63.27 tcf to between 0.65 tcf and 

72.18 tcf.The range for technically recoverable 

oil for the Chukchi Sea has gone 

from between 8.6 billion barrels and 25.0 

billion barrels to between 2.32 billion 

barrels and 40.08 billion barrels.The estimated 

range for natural gas for the 

Chukchi Sea has gone from between 

13.56 tcf and 60.11 tcf to between 10.32 

tcf and 209.53 tcf. 

All of the estimates are for conventional 

resources and do not, for example, 

include gas hydrates, Cooke said. 

Cooke attributes the changes in the 

assessments to changes in the model that 

MMS uses for its assessments and to the 

fact that some new people assessed the 

plays. 

Essentially, geologists evaluate ranges 

of resources that might be associated 

with possible oil and gas pools in each 

oil and gas play in a planning area — 

possible pools are identified from seismic 

data.Then the assessment model combines 

statistically the estimates for individual 

pools into an overall estimate for 

the planning area. Changes in both the 

evaluations of the plays and the method 

of statistically aggregating the pool estimates 

can impact the results of the 

assessment. 

“We count those (pools) up and we 

account for their ranges in sizes … possible 

ranges in thickness of the pay column,” 

Sherwood said, adding that factors 

such as estimated reservoir porosities 

also factor into hydrocarbon volume calculations. 

Sherwood said that the statistical 

method used in the aggregation probably 

played a role in increasing the range of 

uncertainty in many of the total resource 

estimates. 

“I think that’s partly a model effect, 

depending on how you aggregate things,” 

Sherwood said.“The aggregation method 

that is used here would tend to allow the 

extremes to all add up.” 

Cooke also pointed out that the latest 

MMS assessment model allows geologists 

see next page


to use different statistical distributions to 

describe the uncertainties associated 

with resource estimates for individual 

hydrocarbon pools — the previous 

model only allowed a single type of distribution. 

Sherwood said that MMS has made 

some significant changes to its assessment 

of the North Aleutian basin, also known as 

the Bristol Bay basin, that lies on the north 

side of the Alaska Peninsula. In the 1995 

assessment the agency only calculated 

resources for one key play. 

“This time we have six plays, five of 

which we quantified,” Sherwood said, 

commenting that that basin contains 

tremendous potential petroleum reservoirs. 

The 1995 assessment estimated a mean 

of 0.23 billion barrels of conventionally 

recoverable oil and 6.79 tcf of conventionally 

recoverable natural gas for the North 

Aleutian basin.The new assessment has 

increased the mean for oil to 0.75 billion 

barrels and the mean for natural gas is 

now 8.62 tcf. 

The main differences between the new 

MMS assessment and earlier assessments 

come to light in the estimates of economically 

recoverable oil and gas. Calculating 

economically recoverable volumes 

involves postulating different development 

and production scenarios for possible 

oil and gas fields.Then, by estimating 

development costs for the scenarios it is 

possible to estimate how much of the 

technically recoverable resources could be 

viably extracted at various resource price 

levels. 

Although MMS analysts have taken into 

account modern offshore development 

methods such as subsea completions, an 

overall increase of development costs over 

the years has significantly raised the bar 

on the oil and gas price levels at which 

offshore developments become viable. 

MMS economic models hadn’t been 

updated to include cost increases for a 

number of years, Sherwood said. 

For this new assessment the analysts 

used a new, improved economic model to 

incorporate costs consistent with known 

recent costs in the Gulf of Mexico, Cooke 

said.The analysts also had to allow for specific 

Alaska cost issues — the oil and gas 

transportation infrastructure required in 

Alaska is unique to the state, for example. 

Using this approach, MMS analysts 

determined that there would be no economically 

recoverable volumes of oil from 

anywhere on the Alaska outer continental 

shelf at oil prices of $18 per barrel, the 

lowest price level in earlier assessments. 

Even at $30 per barrel, economically 

viable volumes are small — $30 was the 

higher price level in the earlier assessments. 

MMS is now publishing detailed estimated 

economically recoverable volumes 

of oil at $46 per barrel.And, to test the 

potential impact of future high prices, the 

agency has also published estimates at $80 

per barrel. 

For the Beaufort Sea the estimated 

mean volume of economically recoverable 

oil at $46 per barrel is 4.12 billion barrels. 

At $80 per barrel that estimated volume 

increases to 6.92 billion barrels.The corresponding 

volumes for the Chukchi Sea are 

2.37 billion barrels at $46 and 12.0 billion 

barrels at $80. 

For natural gas, economically recoverable 

volumes start to appear at a price 

level of about $4.50 per thousand cubic 

feet. For the Beaufort Sea the estimated 

mean volume of economically recoverable 

gas at $6.96 per thousand cubic feet is 

8.79 tcf.That volume increases to 19.97 

tcf at $12.10 per thousand cubic feet.The 

corresponding volumes for the Chukchi 

Sea are 7.91 tcf at $6.96 per thousand 

cubic feet and 54.44 tcf at $12.10 per 

thousand cubic feet. 

The natural gas estimates assumed the 

existence of a gas export pipeline from 

the North Slope and used estimated tariffs 

for that pipeline to calculate the economics, 

Cooke said. 

For the North Aleutian basin, the estimated 

mean economically recoverable oil 

volumes are 0.63 billion barrels at $46 per 

barrel and 0.74 billion barrels at $80 per 

barrel. Estimated mean economically 

recoverable gas volumes are 5.85 tcf at 

$6.96 per thousand cubic feet and 8.40 tcf 

at $12.10 per thousand cubic feet. 

The analysts assumed that North 

Aleutian gas would ship as LNG to Los 

Angeles or the Cook Inlet. 

MMS has not yet published details of the 

potential hydrocarbon accumulation sizes 

that it estimated for the new assessment. 

However, Sherwood said that these sizes 

are broadly similar to those in the previous 

assessments. In the 2000 assessment MMS 

found the possibility of a giant oil accumulation 

under the Chukchi Sea and estimated 

pool sizes ranging from less than 1 million 

barrels to a little more than 1 billion barrels 

under the Beaufort Sea. 

Sherwood said that the new assessment 

had estimated a maximum gas pool size of 

about 4.5 tcf in the North Aleutian basin. 

“It’s that tremendous reservoir sequence 

out there allowing these big volumes.And 

there are some big structures too,” 

Sherwood said.There is a structure of 

around 100,000 acres for the key play in 

the Aleutian basin, he said. 

And with the preponderance of Alaska 

outer continental shelf petroleum 

resources probably lying under the 

Chukchi and Beaufort seas, those two areas 

together with the North Aleutian basin 

have become the focus of MMS lease planning. 

“Those are all heavily represented in the 

proposed (lease sale) program,” Cooke 

said. 

The new MMS assessment can be 

found at www.mms.gov/alaska/.

Page 32 


Burger delivers 

MMS reappraises Chukchi well; may be largest hydrocarbon find on Alaska OCS 

W 



ith gas prices at major U.S. hubs 

above $5 per thousand cubic feet 

and the prospect of a North Slope 

gas line, MMS is encouraging people 

to look again at a major gas discovery 

in the Burger structure in the Chukchi Sea. 

The Burger well encountered the gas during 

a Chukchi exploration program headed 

by Shell between 1989 and 1991.At the 

time of the discovery people were searching 

for oil rather than gas and paid little 

attention to the gas find. 

A newly released MMS re-appraisal of 

the Burger prospect has lifted the mostlikely 

recoverable reserves from an original 

estimate of 5 trillion cubic feet of conventionally 

recoverable gas to a new estimate 

of 14 tcf.The estimate indicates a possible 

range from 8 tcf to 27 tcf.The corresponding 

estimates for condensate are a mostlikely 

volume of 724 million barrels and a 

range from 371 million to 1.404 billion barrels. 

“We did (the assessment) pretty much 

over from scratch,”Kirk Sherwood, an MMS 

geologist, told Petroleum News Feb. 3.“We 

went ahead and allowed for a more robust 

or complete filling in the prospect … and 

that generated a lot of additional 

resources.” 

MMS actually prepared this new 

appraisal of Burger in 2001 but the agency 

has only just released its report on the 

results to the public. 

In 2001 companies were making development 

decisions based on $12 to $18 oil 

prices, said Larry Cooke, a supervisory geologist 

with MMS.We’re putting the report 

out now because people are looking at 

higher sustained oil and gas prices and 

we’re seeing a situation where this type of 

prospect can become economic, Cooke 

said. 

“We have started getting … enquiries 

about Chukchi from industry,”Cooke 

added. 

And with a known hydrocarbon accumulation 

that is probably very large, Burger 

provides a unique opportunity to assess a 

major prospect in the Chukchi Sea. 

“We selected this as a test object 

because we knew something about it — 

we could estimate some kind of discovered 

resource figure,”Sherwood said. 

The Burger structure consists of a dome 

25 miles in diameter, sitting on a structural 

ridge that branches southwest across the 

center of the Chukchi shelf, from a point 

on the Barrow Arch about 50 miles northwest 

of Barrow.The Jurassic sandstone 

reservoir at Chukchi is part of what geologists 

call the rift or Beaufortian sequence 

— this sequence is associated with the 

pulling apart of the Earth’s crust that 

occurred when the Canada Basin of the 

Arctic Ocean formed. 

The Chukchi sandstone forms an exact 

analogy to similar rift sequence sandstones 

that form the reservoirs at the Kuparuk 

River field in the central North Slope, 

Sherwood said.And the prolific Pebble 

Shale hydrocarbon source rock that also 

occurs on the North Slope caps the Burger 

reservoir. 

At the Burger well the sandstone reservoir 

is just over 100 feet thick and seismic 

data indicates that the reservoir may 

extend at a similar thickness through much 

of the dome. However, seismic interpretations 

of the Burger structure show a threefold 

increase in thickness of the rift 

COURTESY MMS


sequence on the west side of 

the structure, where geologists 

believe that faulting during sedimentation 

has caused thickening 

of the sedimentary 

sequence. If the reservoir sandstone 

has increased in thickness 

in proportion to the rest 

of the sequence, you could find 

300 feet to 400 feet of reservoir 

rock on the west side of the 

structure, Sherwood said. 

Sherwood compared this 

possibility to the thickening of 

the Kuparuk sands in sunken 

fault blocks at Point McIntyre. 

“So we draw upon that analogue 

to infer the potential for 

thick sands on the west side of 

the (Burger) structure,” 


Estimating the amount of 

gas in a prospect such as 

Burger critically depends on 

assessing the total depth of the 

gas column in the reservoir.The 

original 1993 MMS assessment 

of the Burger prospect estimated 

the gas depth by using well 

log data to identify the 

gas/water contact at the base of 

the gas. In particular, geologists 

assumed that the crossover 

point of the pressure gradients 

from the upper and lower parts 

of the reservoir marked the 

gas/water contact — sandstone 

saturated with gas exhibits a 

markedly different pressure gradient 

from sandstone saturated 

with water. 

The geologists then assumed 

that a gas fill down to the 

depth of this inferred gas/water 

interface would represent a 

maximum fill model for the 

prospect. 

The Burger well actually 

drilled through a flank of the 

Burger structure. So, with 

known gas from the Burger 

sandstone, the geologists 

assumed a medium fill model in 

which gas fills the reservoir 

from the crest of the structure 

down to the depth at which 

the well first entered the reservoir 

— a point some 60 feet 

above the gas/water contact 

inferred from the well log data. 

For a minimum fill model 

the geologists assumed the 

same base for the gas as in the 

medium fill model but they 

subtracted a volume associated 

with a seismic “dim spot”at the 

crest of the Burger structure. 

The “dim spot”resulted from 

relatively weak seismic reflections 

and might indicate some 

change in the sandstone or the 

presence of an unconformity. 

“Back in ’93 we said ‘we’re 

worried about that — let’s take 

that out — let’s say that area 

will not have productive reservoir 

in it,’”Sherwood said. 

In its 2001 re-assessment the 

MMS geologists realized that 

large quantities of mud in the 

lower part of the Burger sandstone 

render the interpretation 

of the pressure gradients in the 

well unreliable. In fact, there is 

a distinct boundary between 

clean sands in the upper 60 

feet of the drilled Burger sandstone 

section and the muddy 

sands of the lower 40 feet of 

the sandstone.A divergence 

between the neutron porosity 

and density log porosity curves 

from the well logs marks this 

boundary; the boundary also 

coincides with the crossover 

point of the pressure gradient 

curves. It’s likely that below the 

boundary the mud masks the 

effect of any gas on the pressure 

gradient, Sherwood said. 

“The upper part of the sandstone 

… is clean, it’s a nice high 

permeability sand — the lower 

part’s muddy and has less permeability,”Sherwood 

said.“Also 

the mud acts to cancel those 

gas effects (on the pressure gradient).” 

So the geologists now think 

that gas may fill the whole of 

the sandstone unit around the 

well.And the reported recovery 

of some gas and condensate 

from within the muddy layer 

below the pressure gradient 

crossover point supports this 

view. 

But where is the base of the 

gas column in the Burger reservoir 

In the absence of delineation 

wells no-one knows. 

However, it’s reasonable to conclude 

that gas can’t have accumulated 

below a spill point at 

the lowest point in the trap 

that seals the reservoir. So, the 

2001 reassessment used an estimate 

of this spill point to determine 

the maximum fill model 

for the reservoir.This approach 

resulted in a much larger potensee 

next page 

COURTESY MMS

Page 34 


tial volume of gas than in the 

1993 assessment. 

For the medium fill model, 

the 2001 reassessment used the 

exact same model as the maximum 

fill model of the 1993 

assessment, with the gas fill 

extending down just to the 

pressure curve crossover point. 

The 2001 minimum fill corresponds 

to the 1993 medium fill 

model and assumes a base for 

the gas fill at the point where 

the well first entered the reservoir.The 

2001 re-assessment 

did not consider the seismic 

“dim spot”as a significant factor. 

In calculating conventionally 

recoverable reserves, the MMS 

assessment team applied some 

statistical analysis to the uncertainties 

associated with the 

maximum, medium and minimum 

fill models.This analysis 

resulted in a mean volume and 

possible range of volumes for 

each of the models. 

The team’s estimate of 14 

tcf as the most likely volume of 

gas in the Burger reservoir corresponds 

to the mean value for 

the medium fill model.The likely 

range of 8 tcf to 27 tcf corresponds 

to the range from most 

likely to mean for the maximum 

fill model.The team 

derived the estimated condensate 

volumes in the same way. 

The upper end of the statistical 

range for gas in the maximum 

fill model gives a volume 

of 63 tcf but this volume of gas 

would require a combination of 

circumstances that seems very 

improbable. 

To assess the economics of 

developing the Burger prospect 

MMS had to consider how best 

to extract gas from a wide area 

in a remote offshore location. 

“What we have here is basically 

… a thin reservoir spread 

over a large area and what ultimately 

controls your economic 

success is concentration of 

resources per well site,” 


So MMS petroleum geologist 

Jim Craig proposed the use of 

subsea well completions 

hooked into a single concrete 

platform. 

“In the past we’ve modeled 

a fairly large number of platforms 

and one of the big 

changes that Jim had this time 

is that he had a single platform 

and had subsea completions to 

lower the cost,”Cooke said. 

The MMS development scenario 

also assumes an 80-mile 

subsea gas pipeline from the 

platform to land and a 300-mile 

overland pipeline direct to a 

compressor station at the 

northern end of a gas line from 

the North Slope. 

Craig compared Burger with 

several offshore gas fields in 

various parts of the world by 

plotting a graph of the development 

cost per thousand cubic 

feet of gas vs. field size. It turns 

out that Burger is probably bigger 

than any of these fields and 

could cost less per thousand 

cubic feet of gas than several 

fields in the North Sea. 

“Burger amongst these 

(fields) would be a relatively 

high-cost project but also offers 

at the mean case a pretty good 

resource base,”Sherwood said. 

The Norwegian Asgard field 

provides a good analogue for 

Burger, Cooke said.The Asgard 

field uses subsea completions 

in similar water depths. 

Plugging the estimated 

development costs and gas 

reserves into a standard economic 

model resulted in a 

breakeven point for the development 

at a natural gas price 

of about $5 per 1,000 cubic 

feet. 

“The standard NPV (net present 

value) model … that 

allows costs and gas prices to 

inflate at the same rate yielded a 

$5 (per thousand cubic feet) 

year 2000 price paid in Chicago 

to basically break even,” 


And the economic model 

predicted an economic field life 

of about 22 years, with 11 tcf of 

economically recoverable gas 

and 600 million barrels of economically 

recoverable condensate. 

The MMS economic model 

also shows how different economic 

assumptions such as gas 

price inflation, general price 

inflation and discount rates 

affect the threshold gas price 

for a viable development project.Assuming 

a growth in gas 

prices 1 percent above general 

price inflation results in a 

threshold gas price of just 

$4.63 per thousand cubic feet. 

The standard model, but with 

no condensate sales, gives a 

threshold price of $6.71.The 

highest threshold price, $8 per 

mcf, results from an assumption 

that gas prices will remain flat. 

Although the results of the 

resource assessment and economic 

analysis show a prospect 

that is on the verge of being 

economically attractive, 

Sherwood emphasized the 

many uncertainties that the 

MMS report addresses. For 

example, huge unknowns 

remain concerning the exact 

nature of the Burger prospect. 

“It’s a single well test of a 

structure that’s 25 miles in 

diameter and a sand that’s 

about 100 feet thick,”Sherwood 

said.The discovery of a thicker 

area of reservoir on the faulted 

western side of the structure 

could, for example, make a big 

impact on the economics of 

the prospect. 

But even with the volumes 

that MMS has now assessed, 

Burger may be the largest discovery 

on the outer continental 

shelf and could rank alongside 

some of the larger hydrocarbon 

accumulations on the North 

Slope. 

“Even in our minimum case 

now — 7 tcf — that would be 

up there with Point 

Thompson,”Sherwood said.“At 

the mid case on a barrels-of-oil 

equivalent it’s about 3 billion 

barrels … that’s a Kuparuk 

size.” 

The MMS report and a 

spreadsheet with the Burger 

economic model are available 

online at 

http://www.mms.gov/alaska/re 

/BurgerReserves/Burger Fact 

Sheet.pdf.


Page 36 

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