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Technology
Assessment & Research (TA&R) Program
| Project Number |
432 |
| Date of Summary |
January 16, 2008 |
| Subject |
Regional Synthesis of the Sedimentary Thermal History and Hydrocarbon
Maturation in the Deepwater Gulf of Mexico |
| Performing Activity |
Texas Tech
University |
| Principal Investigator |
Dr. Seiichi Nagihara |
| Contracting Agency |
Minerals Management Service |
| Estimated Completion |
Completed July 28, 2006 |
| Description |
The goal of this project, in Phase I, was to construct
regional models for the sedimentary thermal history and hydrocarbon
maturation in the Deepwater of the Gulf of Mexico. Phase II is a pull back to the shallower waters of the GOM
with attention given to the deep strata (below 5 km or 16,400 feet) where
MMS sees the potential for 5 to 20 trillion cubic feet of undiscovered gas.
Drilling for the deep gas can be very expensive because of risks associated
with high pressure and high temperatures. One of the most serious risks is
that produced gas from deep strata may contain very high concentrations of
hydrogen sulfide (H2S) since high temperature conditions is favorable for
the thermo-chemical sulfate reduction processes that produce H2S, a product
both extremely toxic and corrosive. By knowing the heat profile of adjacent
wells and the down-hole variation of individual heat flow trends, geologists
can extrapolate temperatures to develop a thermal regime of deep sediments
to help evaluate potential risks of H2S. With this information, Phase II
produced deep thermal gradient maps of potentially H2S contaminated
zones and computer simulation software through completion of these four
tasks:
1. Geothermal gradient calculation for each well,
2. Establish the thermal conductivity variation in
function of depth per well,
3. Estimate the radiogenic heat production in each
well,
4. Create the Bullard plots for the heat simulation
model for zones beneath the
measured well depths. |
| Progress |
Phase I of the project began in 2002 followed
by Phase II in July of 2004; both involving the collection and
examination of hundreds of sets of well logs from the deepwater GOM examined
leading toward mapping of
deep geothermal gradients within
the continental shelf of the Gulf of Mexico. Phase
II was completed in July 2006.
The Phase I and Phase II deliverables are provided in the Reports
Section below. The GIS database used to develop the thermal history
mapping, consisting of 27 files (11mb, is available on CD free of
charge by contacting Mr. Michael Else at
michael.else@mms.gov and providing your name and mailing
address. Delivery is generally made within 10 business days. |
| Report |
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AA
(5 pages) |
Phase I (2003) Nagihara, S., Regional Synthesis of the Sedimentary
Thermal History and Hydrocarbon Maturation in the Deepwater Gulf of Mexico,
Texas Tech University, October, 2003. |
|
AB
(25 pages, 1 MB) |
Phase I (2003) BHT presentation |
|
AC
(14
pages) |
Deep Sedimentary
Thermal History of the Texas-Louisiana
Continental Shelf, Gulf of Mexico, Dr.
Seiichi Nagihara, Texas Tech University, July
24, 2006. |
|
AD
(17 pages) |
GIS
Database Instructions, July
2006, by Dr.
Seiichi Nagihara of Texas Tech University, Lubbock, TX. |
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