Wilcox sandstone reservoirs in the deep subsurface along the Texas Gulf Coast: their potential for production of geopressured geothermal energy. Report of Investigations No. 117

Technical Report · Fri Jan 01 00:00:00 EST 1982

DOI:https://doi.org/10.2172/6140725· OSTI ID:6140725

Debout, D G; Weise, B R; Gregory, A R; Edwards, M B

Regional studies of the lower Eocene Wilcox Group in Texas were conducted to assess the potential for producing heat energy and solution methane from geopressured fluids in the deep-subsurface growth-faulted zone. However, in addition to assembling the necessary data for the geopressured geothermal project, this study has provided regional information of significance to exploration for other resources such as lignite, uranium, oil, and gas. Because the focus of this study was on the geopressured section, emphasis was placed on correlating and mapping those sandstones and shales occurring deeper than about 10,000 ft. The Wilcox and Midway Groups comprise the oldest thick sandstone/shale sequence of the Tertiary of the Gulf Coast. The Wilcox crops out in a band 10 to 20 mi wide located 100 to 200 mi inland from the present-day coastline. The Wilcox sandstones and shales in the outcrop and updip shallow subsurface were deposited primarily in fluvial environments; downdip in the deep subsurface, on the other hand, the Wilcox sediments were deposited in large deltaic systems, some of which were reworked into barrier-bar and strandplain systems. Growth faults developed within the deltaic systems, where they prograded basinward beyond the older, stable Lower Cretaceous shelf margin onto the less stable basinal muds. Continued displacement along these faults during burial resulted in: (1) entrapment of pore fluids within isolated sandstone and shale sequences, and (2) buildup of pore pressure greater than hydrostatic pressure and development of geopressure.

• Research Organization: Texas Univ., Austin (USA). Bureau of Economic Geology
• DOE Contract Number: AS05-76ET28461
• OSTI ID: 6140725
• Report Number(s): DOE/ET/28461-T2; ON: DE83011100
• Country of Publication: United States
• Language: English

Related Subjects

15 GEOTHERMAL ENERGY
GEOPRESSURED SYSTEMS
GEOLOGY
RESOURCE POTENTIAL
TEXAS
GEOLOGIC FAULTS
GEOTHERMAL FLUIDS
MAPPING
METHANE
SANDSTONES
SHALES
ALKANES
ENERGY SYSTEMS
FEDERAL REGION VI
FLUIDS
GEOLOGIC STRUCTURES
HYDROCARBONS
NORTH AMERICA
ORGANIC COMPOUNDS
ROCKS
SEDIMENTARY ROCKS
USA
Geothermal Legacy
150201* - Geology & Hydrology of Geothermal Systems- USA- (-1989)
150101 - Geothermal Energy- Resources & Availability- USA- (-1989)