Quartz Cementation History of the Heidelberg Sandstone, Germany ...

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Quartz Cementation History of the Heidelberg Sandstone, Germany ...

Quartz Cementation History of the Heidelberg Sandstone, Germany: In Situ Microanalysis of δ18O*

Marsha French 1 , Richard H. Worden 2 , Elisabetta Mariani 2 , Hubert E. King 3 , William A. Lamberti 3 , and William C. Horn 3

Search and Discovery Article #50705 (2012)**

Posted August 31, 2012

*Adapted from oral presentation at AAPG Annual Convention and Exhibition, Long Beach, California, April 22-25, 2012

**AAPG © 2012 Serial rights given by author. For all other rights contact author directly.

1 ExxonMobil Upstream Research C, Houston, TX (marsha.w.french@exxonmobil.com)

2 School of Environmental Sciences, University of Liverpool, Liverpool, United Kingdom

3 ExxonMobil Research and Engineering Company, Annandale, NJ

Abstract

Microcrystalline quartz prevents the growth of ordinary quartz cements and leads to anomalously high porosity in deeply buried petroleum

reservoirs. Oxygen isotope analysis of microcrystalline quartz and other quartz cements provide data to help understand the growth mechanisms

for porosity preserving microcrystalline quartz. High precision, in situ oxygen isotope analyses of Cretaceous Heidelberg Formation detrital grains

and quartz cements show three varieties of authigenic quartz cement growing on detrital quartz grains. This micron-scale data provides evidence

that: (1) Porosity preserving microcrystalline quartz forms on a chalcedony substrate, and (2) that there were two episodes of fluid influx into the

Heidelberg Formation.

Detrital quartz has an average δ18O composition of +9.40/00 and mesoquartz (syntaxial overgrowth) has an average composition of +19.30/00,

microcrystalline quartz has an average composition of 21.70/00. Estimates of the δ18O composition of chalcedonic quartz are complicated by the

problem of isolating the microcrystalline quartz from the chalcedony; mixtures of the two give a consistently higher δ18O (27.40/00) than

microcrystalline quartz. From oxygen isotope data, the formation of microcrystalline quartz and chalcedonic quartz is interpreted to have taken

place in a small temperature range of between 80 and 140° C. Wavelength dispersive spectroscopy (WDS) data supports the paragenetic data and

suggests that two episodes of enrichment in aluminum and iron in the microcrystalline quartz and chalcedony. These two distinct layers formed

from two episodes of highly concentrated brines, emanating from a hydrothermal source associated with nearby faulting in the Harz Mountains

mining district, Germany.


Selected References

Aase, N.E., P.A. Bjorkum, and P.H. Nadeau, 1996, The effect of grain-coating microquartz on preservation of reservoir porosity: AAPG Bulletin,

v. 80/10, p. 1654-1673.

Abruzzese, M.J., J.R. Waldbauer, and C.P. Chamberlain, 2005, Oxygen and hydrogen isotope ratios in freshwater chert as indicators of ancient

climate and hydrologic regime: Geochimica et Cosmochimica Acta, v. 69/6, p. 1377-1390.

Blatt, H., 1987, Oxygen isotopes and the origin of quartz: Perspective: JSR, v. 57/2, p. 373-377.

Knauth, L.P., and S. Epstein, 1976, Hydrogen and oxygen isotope ratios in nodular and bedded cherts: Ceochimica et Cosmochimica Acta, v.

40/9, p. 1095-1108.

Marchand, A.M.E., C.I. Macaulay, R. S. Haszeldine, and A.E. Fallick, 2002, Pore water evolution in oilfield sandstones; constraints from oxygen

isotope microanalyses of quartz cement: Chemical Geology, v. 191/4, p. 285-304.

Murata, K.J., I. Friedman, and J.D. Gleason, 1977, Oxygen isotope relations between diagenetic silica minerals in Monterey Shale, Temblor

Range, California: American Journal of Science, v. 277/3, p. 259-272.

Pollington, A.D., R. Kozdon, and J.W. Valley, 2011, Evolution of quartz cementation during burial of the Cambrian Mount Simon Sandstone,

Illinois Basin; in situ microanalysis of delta (super) O: Geology, v. 39/12, p. 1119-1122.

Vagle, G.B., A. Hurst, and H. Dypvik, 1994, Origin of Quartz cements in some sandstones from the Jurassic o the Inner Moray Firth (UK):

Sedimentology, v. 41/2, p. 363-377.

Waldman, S., C. Fischer, and H. von Eynatten, 2006, Räumliche Diageneseaniostropien in kretazischen Quarzareniten: Schriften der Deutschen

Gesellschaft für Geowissenschaften, v. 45, p. 181.

Williams, L.B., K. Bjorlykke, and R.L. Hervig, 1997, New evidence for the origin of quartz cements in hydrocarbon reservoirs revealed by oxygen

isotope microanalyses: Geochimica et Cosmochimica Acta, v. 61/12, p. 2529-2538.


Quartz Cementation History

of the Heidelberg Sandstone:

In Situ Microanalysis of δ 18 O

AAPG

Diagenetic Effects on Clastic Reservoirs

April 25, 2012

Porosity

Porosity

Marsha French - ExxonMobil Upstream Research Co.

Richard Worden and Betty Mariani - University of Liverpool

Hubert King, Bill Lamberti, and Bill Horn – ExxonMobil Corporate Strategic Research Company

Qtz

Porosity

μQtz

Am. Silica

μQtz


Overview

1) Porosity preserving mechanism microquartz

2) Origin of microquartz = early meteoric diagenesis

3) Isotope data confirms low temperature

2/12


Geologic Setting

TS 2

TS 3

TS 3

Quartz –cemented Sand Ridge

“Teufelsmaurer”

Quartz Sand

TS 2 & 3

TS 2

Porosity

Microquartz Sand

Microquartz

3/12

Heidelberg Fm (Cretaceous)

Sand Quarry (400 m. away)

Unconsolidated Sand

Waldman, S., Fischer, C., von Eynatten, H., 2006, Räumliche Diageneseaniostropien in kretazischen Quarzareniten: Schriften der Deutschen Gesellschaft für Geowissenschaften, v. 45, p. 181.

TS 1

TS 1

Unconsolidated

Sand


Methods

TS

200 μm

d

Quartz

Overgrowth

Porosity

SEI

CL EBSD

Porosity

BSE Image

Red CL image

200 µm

4/12

Porosity

Porosity

C D

BSE

d

200 μm

100 µm

Qtz.

OG

1

2 3

4

µQ

Porosity

A

Detrital


EBSD Orientation

c-axis

=200 µm; BC+E1-3 ; Step=0.75 µm; Grid796x744

Porosity

Girdle of microquartz rotating about the c-axis.

The trace of a great circle matches the

orientation of the face of the detrital grain on

which the microquartz is growing.

�EBSD evidence indicates that the crystals of

microquartz have grown with their c-axes

parallel to the surface of the grain like lengthfast

chalcedony.

5/12

TEM

Microdiffraction Spot 1

0.20 µm

1000 nm

TEM sample from FIB

TEM

Bright-field TEM Image

SAD Spot #5 1

Microdiffraction Spot 2

100 nm

100 nm

Nanocrystalline quartz

The c-axis growth

is controlled by

the surface

SAD Spot #4 2

material, a-axis is

random


Secondary Ion Mass Spectrometry

Cameca N50 Nano SIMS

Sample Area

UW-1 Standard

TS

XOM Corporate Strategic Research

Clinton, New Jersey

N50 = 50nm resolution

CL

δ 18 O Locations: Scan 1, 2, and 3

b

6/12

8

11 22

Scan 1

14

Porosity

22

32


δ 18 O Values (V-SMOW)

1 2

3

11

22

Porosity

CL CL CL

Scan 1

8

7/12

14

Porosity

22

Porosity

Scan 2 Scan 3

8 14

Sample number Sample number Sample number

CH

DG

30

24

23

MQ

21

OG

19

12

7

32


Calculated Temperature Curves

Temperature °C

200

180

160

140

120

100

80

70

60

40

20

0

δ

20.3 Quartz overgrowth

18O values

22.7

27.4

57o Quartz overgrowth

o

Microcrystalline quartz

34 o

Chalcedony

Microcrystalline quartz

Chalcedony

Meteoric Oceanic Magmatic

-10.0 -5.0 0.0 5.0 10.0

δ18O-H2O ‰

8/12

Using Clayton et al., 1972


Trace a Element Analysis

Concentration (Wt.%) 1.0

Quartz Overgrowth

µQ

Amorphous

silica

Chalcedony

Sample Number 9/12

Qtz

OG

Detrital

Amorphous

silica

Chalcedony

Mq Mq

Sodium

Magnesium

Potassium

Calcium

Titanium

Iron

Chromium

Manganese

Aluminum


Conclusions

∅ 200 nm

step size

Sandstone of the “Teufelsmauer” (“Devil’s Wall”), Heidelberg Formation

1) Porosity preserving mechanism microquartz

2) Origin of microquartz = early meteoric diagenesis

3) Isotope data confirms low temperature

Generalized Silica Sinter Sequence

Amorphous/Opal-A → Opal-CT → Chalcedony → Microquartz

10/12

Step = 0.2 µm

δ 18 O Temp.

Microquartz +22.7‰. 57°C

Chalcedony +27.4‰ 34 ° C

Overgrowth +20.3‰ 70 ° C


Isotope Values versus Literature

Oxygen Isotope Values from the Heidelberg Formation versus Literature in V-SMOW

DG OG MQ MQ/Chal. Cristobalite Bio. Opal

Heidelberg Fm. Average 9.4 20.3 22.7 27.4

Literature Average 12.2 20.0 23.8 28.3 29.4 37.4

Heidelberg Fm. Range 7.7_12.4 19.0_21.9 21.0_23.5 24.5_30.8

Literature Range 4.2_24.1 12.6_32.4 24.9_32.4 27.9_30.4

Heidelberg Formation silica polymorphs:

DG = Detrital Silica

OG = Quartz Overgrowths

MQ = Microcrystalline Quartz

MQ/Chal. = Microquartz and Chalcedony

Literature data from: Blatt, 1987; Vagle et al., 1994; Murata et al., 1977; Harwood et al., 2010; Pollington et al., 2011; Marchand et

al., 2002; O’Neil and Hay, 1972; Knauth and Epstein, 1976; Abruzzese et al., 2005; Williams et al., 1997; and Harvig et al., 1995.

11/12


Porosity Uplift from Microquartz Coatings

Porosity %

Depth

(km)

0

1

2

Porosity uplift 3 of

15 - 20%

4

5

6

0 10 20 30 40 50

Data point

Microquartz effect

Central N. Sea Fulmar, Ajdukiewicz, 1994, U. Jurassic sands at 3 to 4 km

in the Southern North Sea (Aase et al., 1996)

12/12

Compaction

Compaction +

microquartz

Compaction +

cementation

Central North Sea Fulmar Fm.

3697m

6368m

6493m

300 µm

250 µm

250 µm

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