The Bakken/Exshaw Petroleum System Advisory...
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The Bakken/Exshaw Petroleum System Advisory Board Stephen A. Sonnenberg Colorado School of Mines
Transcript of The Bakken/Exshaw Petroleum System Advisory...
The Bakken/Exshaw Petroleum System
Advisory Board
Stephen A. Sonnenberg
Colorado School of Mines
Colorado School of Mines
Bakken Consortium
Mike Johnson &
Associates
Colorado School of Mines
Bakken Consortium
Username: guest-bakres
Password: qp24y4mb
Rock’n in the Bakken
Acknowledgements
• Mike Lewan, USGS
• Julie LeFever, NDGS
• Mike Hendricks, Hendricks & Associates
Projects
• Elm Coulee III
– 3-D seismic
– Reservoir model
• Three Forks
– Diagenesis, mineralogy, fractures, EOD, saturation, reservoir characterization
– Petrophysical Model
– Breccia types
– Which intervals produce??
• Pronghorn
• Lodgepole play
• Secondary/Tertiary Recovery
• Dolomitization
• Sequence strat
• Provenance
– XRF, etc
• Best Practices
Modified from Smith et al.
Modified from Smith et al.
Lodgepole
Upper
Three Forks (D)
Middle
Three Forks (C)
Nisku\Birdbear
Upper Bakken Shale
Middle Bakken
Lower Bakken Shale
Lower
Three Forks (A)
Lower
Three Forks (B)
EOG Liberty 2-11H
Sec. 11-T151N-R91W
?
Scallion
False Bakken
?
?
Ba
kke
n P
etro
leu
m S
yste
m
The Line of Death
Steve Sonnenberg
Colorado School of Mines
Meissner, 1978
“Relationship between source-rock
maturity, hydrocarbon generation,
geopressuring and fracturing
suggest an opportunity in
exploration for unrecognized and
unlooked-for “unconventional”
accumulations of potentially very
large regional extent”
Key Publications
• Meissner, F. F., 1978, Petroleum geology of the Bakken formation,
Williston Basin, North Dakota and Montana, in Estelle, D., and
Miller, R., eds., The Economic Geology of the Williston Basin, 1978
Williston Basin Symposium, Montana Geological Society, p. 207-
230 • Hester, T.C., and J.W. Schmoker, 1985, Selected physical
properties of the Bakken Formation, North Dakota, and Montana
part of the Williston Basin: U.S. Geological Survey, Oil and Gas
Investigations Chart, chart OC-126.
LOD
0
2000
4000
6000
8000
10000
12000 0 25 50 75 100
Electrical Resistivity, ohm-meters
We
ll D
ep
th,
fee
t
Average Line
SHALLOW, LOW RESISTIVITY TREND
REPRESENTS COMPACTION OF A
SALT WATER-SATURATED ORGANIC-
RICH CALCAREOUS SHALE
DEEP, HIGH RESISTIVITY
CHARACTER
REPRESENTS A HYDROCARBON-
WET & SATURATED SOURCE ROCK
WHICH HAS GENERATED OIL
AND/OR GAS
FPG
0.54 PSI/FT
0.50 PSI/FT
0.73 PSI/FT
0.64 PSI/FT
Resistivity
and Bakken
hydrocarbon
generation,
depth: >6500’
“The existence of this
wide depth range
suggests that the actual
depth of hydrocarbon
generation is not uniform
throughout the basin”
“the point at which
hydrocarbon generation
starts is actually more
directly related to
temperature than depth”
DEPTH RANGE THROUGH
WHICH HYDROCARBONS
ARE GENERATED
Modified from Meissner, 1978
Suggested
temperature of HC
generation = 165oF or
74oC
500
1000
1500
2000
2500
3000
3500
0 25 50 75 100
ELECTRICAL RESISTIVITY ohm-meters
BA
KK
EN
SU
BS
UR
FA
CE
TE
PM
ER
AT
UR
E,
F
SHALLOW LOW RESISTIVITY TREND
SUGGESTED TEMPERATURE OF
HYDROCARBON GENERATION AT 1650F
30 ohm-m
= mature source rocks
Modified from Meissner, 1978
100 ohm-m
= mature source rocks
& expulsion
Change in pore-
fluid volume
(porosity) and pore-
fluid species which
may accompany
hydrocarbon-
generation
(maturity) in source
rocks
Meissner, 1978
Water Wet
Oil Wet
Lower Bakken Res
Upper Bakken Res
Limit Middle
Bakken
Limit Lower
Bakken Shale
Limit Upper Bakken Shale CCA
Structure
Bakken Formation
50 miles
Resistivities Bakken Shales Resistivity lines from Hester & Schmoker, 1985
Middle Bakken & the LOD
Modified from Whiting, 2010
Isopach Middle Bakken
&
Bakken Producers LOD
Isopach Lower
Bakken Shale
&
Bakken, Three Forks Producers
Isopach Lower
Bakken Shale
&
Bakken, Three Forks Producers
&
100 ohm-m shale line
Isopach Lower
Bakken Shale
&
Three Forks Producers
&
100 ohm-m shale line
Isopach Upper
Bakken Shale
&
Bakken, Three Forks Producers
Isopach Upper
Bakken Shale
&
Bakken, Three Forks Producers
&
100 ohm-m Res Lines
Upper Shale
100 ohm-m
Lower Shale
100 ohm-m
Isopach Upper
Bakken Shale
&
Three Forks Producers
&
100 Res Lines
Upper Shale
100 ohm-m
Lower Shale
100 ohm-m
Isopach
Middle Bakken
&
Bakken, Three Forks Producers
&
100 Res Lines
Upper Shale
100 ohm-m
Lower Shale
100 ohm-m
Pressure (Middle Bakken)
92 BHP and DFIT data points + 6 hydrostatic points at eastern margin + 6 Sanish-Parshall points
No DST data
P Gradient (psi/ft)
Lower Bakken
Shale 100 ohm-m
Line
(H&S, 1985)
Theloy, 2012
Summary
• Resistivities in the LBS of > 100 ohm-m seem to reflect the production limits of the Middle Bakken and Three Forks
• The over-pressure boundary is coincident to the LBS 100 ohm-m line
• The Upper shale sources the Three Forks and Pronghorn in the southern WB
• The new Bakken play in NE Montana (NE Elm Coulee) is charged from both the UBS and LBS and where middle Bakken is 30 to 40 ft thick
Colorado School of Mines
Bakken Consortium
Mike Johnson &
Associates
Lower Bakken Shale Mean Resistivity
Upper Bakken Shale Mean Resistivity
