WENSRICH, MARTIN D., Occidental Oil and Gas Company, Houston, TX; and EDWARD E. CLERKE, Clerke Enterprises, Houston, TX
The Karst Reservoir Play is one of 10 clastic and carbonate play types
that are currently being evaluated by the Occidental Oil and Gas staff along the
Cretaceous Shelf Margin Trend in the Gulf of Mexico, U.S.A. The Karst Reservoir Play may
be from a volumetric perspective the most significant play type in the trend, but it also
carries one of the highest risks for commercial production. The traditional geologic model
for karst reservoir development invokes carbonate dissolution by ground water along
fracture planes. However, sulfuric acid derived from hydrocarbons may also play a
significant role. Analogues from outcrops and fields in the Permian Basin of west Texas
show that the reservoirs in this play type can yield rates of over 3000 barrels of liquids
per day and that 100 million barrel fields may have an aerial extent of less than 200
acres. Geophysical modeling
shows that there is a distinct
seismic
attribute response for
the reservoir that can be quantified.
Seismic
workstation mapping techniques combined with
the modeled
seismic
attribute characteristics can be used to generate prospects on 2D and
3D
seismic
data. Examples of prospects along the Cretaceous Shelf Margin Trend in the Gulf
of Mexico, U.S.A. are shown.
WENSRICH, MARTIN D., and EDWARD E. CLERKE
AAPG Search and Discovery Article #90908©2000 GCAGS, Houston, Texas