Tectonic and hydrologic control of the nature and distribution of geothermal resources

Journal Article · Mon Nov 01 00:00:00 EST 1993 · Geo-Heat Center Quarterly Bulletin; (United States)

OSTI ID:5462134

Muffler, L J.P. ^[1]

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1. Geological Survey, Menlo Park, CA (United States)

A broad overview of the geologic controls of the nature and distribution of geothermal resources is presented. Under forseeable economics and technology, extraction of geothermal resources is limited to the upper few kilometres of the earth's crust. At these depths, the global distribution of geothermal resources is primarily controlled by plate-tectonic features. Geothermal resources related to igneous intrusions in the upper crust occur along spreading ridges, subduction zones, inter-arc basins, and melting anomalies. Geothermal resources unrelated to igneous intrusions in the upper crust occur most commonly in porous sedimentary rocks near convergent or divergent plate boundaries where regional heat flow is high. Geothermal reservoirs at pressures well in excess of hydrostatic occur commonly in young tectonic basins characterized by high rates of sedimentation and subsidence; these reservoirs are commonly termed [open quotes]geopressured.[close quotes] The hydrologic properties of crustal rocks are very important in determining location, size, and type of geothermal resource. Hot dry rock can result from solidification of a young intrusive body or from conductive heating of impermeable rock around such a body. Convective hydrothermal systems result either from convection of meteoric water around young intrusive bodies or from deep circulation of meteoric water along fracture zones. Geopressured reservoirs are formed in deep sedimentary basins when escape of connate water and water produced by the thermal dehydration of clays is impeded by sediments of low permeability.

• OSTI ID: 5462134
• Journal Information: Geo-Heat Center Quarterly Bulletin; (United States), Vol. 15:2; ISSN 0276-1084
• Country of Publication: United States
• Language: English

Related Subjects

15 GEOTHERMAL ENERGY
EARTH CRUST
HEAT TRANSFER
GEOTHERMAL RESOURCES
HYDROLOGY
PLATE TECTONICS
GEOPRESSURED SYSTEMS
HOT-DRY-ROCK SYSTEMS
IGNEOUS ROCKS
MAGMA
PRESSURE DEPENDENCE
SEDIMENTARY BASINS
ENERGY SYSTEMS
ENERGY TRANSFER
GEOLOGIC STRUCTURES
GEOTHERMAL SYSTEMS
RESOURCES
ROCKS
TECTONICS
150100* - Geothermal Energy- Resources & Availability