Resource Assessment Status Report on Geothermal Energy within Deep Sedimentary Basins in Texas
Richard J. Erdlac, Jr.1, Linda Armour2, Robert Lee3,
Susan Snyder2, Mike Sorensen2, Mike Matteucci2, and Jordan Horton2
1 Energy America Geothermal, 303 Veterans Airpark Ln., Ste. 4101, Midland, Texas 79705
2 Center for Energy and Economic Diversification, The University of Texas of the Permian Basin, 4901 E. University, Odessa, Texas 79762
3 Lee Engineering, P.O. Box 10523, Midland, Texas 79702
Resource assessment studies, most recently funded by a U.S. Department of Energy (DOE) grant, show that a large heat resource lies untapped within deep sedimentary basins. Long considered a liability by the oil and gas industry and uninvestigated by the geothermal industry, this sleeping giant of heat energy may boast many thousands of exajoules waiting to be tapped for electrical power production. Subsurface temperature-depth (t-d) recordings from oil and gas log header information is readily accessible and very useful for determining minimum temperature encountered in the deep subsurface. Temperatures from 250°F (121°C) to over 400°F (204°C) are found at varying depths and in different geographical areas of Texas. Presently, five large areas are defined that have strong potential for use in developing geothermal electric. A sixth area may also exist as an independent geologic environment for geothermal development.
A database containing 8050 t-d recordings from log headers has been generated in eight target counties in the Delaware – Val Verde basins of West Texas. Temperatures of the deepest gas wells range to 400°F (204°C) and above. Empirical evaluation of the data generated non-linear t-d curves that can be used to determine heat flux values in subsurface target sedimentary rocks. No experimental information yet exists on conductivity for target formations. Temperature maps within target formations are still to be developed. High potential exists to be able to reenter abandoned and plugged wells and use these wells for water extraction and injection within water-wet formations.
AAPG Search and Discover Article #90069©2007 GCAGS 57th Annual Convention, Corpus Christi, Texas