Geochemical behavior of the second hot dry rock geothermal reservoir at Fenton Hill, New Mexico

Technical Report · Tue Jan 01 04:00:00 EST 1980

DOI:https://doi.org/10.2172/6743767· OSTI ID:6743767

Grigsby, C O; Trujillo, Jr, P E; Counce, D A; Aguilar, R G

The results of three major heat-extraction experiments conducted in two hot dry geothermal reservoirs indicate that the field chemistry is largely influenced by the interstitial fluid contained in the reservoir rock. This fluid is slowly removed by the circulation of relatively fresh water through the fracture systems until the level of dissolved species is ultimately fixed by rock-water equilibrium. Because the sodium and potassium observed in the system were contributed by the pore-fluid, the Na-K-Ca geothermometer was insensitive to changes in the rock temperatures. The quartz geothermometer does reflect the changes in reservoir temperature, however the concentraton of silica in solution must be adjusted for the effect of mixing of small amounts of silica-saturated pore-fluid with fluid which has passed through the main flow path. When the pore-fluid contribution is subtracted, the resulting concentration of silica in the produced fluid can be modeled with a kinetic model to determine the actual temperature of the reservoir rock.

• Research Organization: Los Alamos Scientific Lab., NM (USA)
• DOE Contract Number: W-7405-ENG-36
• OSTI ID: 6743767
• Report Number(s): LA-UR-80-3523
• Country of Publication: United States
• Language: English

Related Subjects

15 GEOTHERMAL ENERGY
150302* -- Geothermal Exploration & Exploration Technology-- Geochemical Techniques & Surveys
ALKALI METALS
CHALCOGENIDES
CHEMICAL COMPOSITION
CHEMICAL REACTION KINETICS
CHEMISTRY
ELEMENTS
FLUIDS
GEOCHEMISTRY
GEOTHERMAL FLUIDS
GEOTHERMAL SYSTEMS
GEOTHERMOMETRY
GROUND WATER
Geothermal Legacy
HEAT EXTRACTION
HOT-DRY-ROCK SYSTEMS
HYDROGEN COMPOUNDS
INTERSTITIAL WATER
KINETICS
METALS
MINERALS
NEW MEXICO
NORTH AMERICA
OXIDES
OXYGEN COMPOUNDS
POTASSIUM
QUARTZ
REACTION KINETICS
RESERVOIR ROCK
RESERVOIR TEMPERATURE
ROCK-FLUID INTERACTIONS
SILICA
SILICON COMPOUNDS
SILICON OXIDES
SODIUM
SOUTHWEST REGION
USA
WATER