Stable isotope investigation of fluids and water-rock interaction in the Roosevelt Hot Springs thermal area, Utah

Technical Report · Mon Jan 01 04:00:00 EST 1979

DOI:https://doi.org/10.2172/5911506· OSTI ID:5911506

Bowman, J R

Carbon-hydrogen-oxygen isotope compositions have been measured in regional cold waters, geothermal fluids, and hydrothermally altered rocks from the Roosevelt Hot Springs geothermal area. These data have been used, in conjunction with other geological and geochemical data from this geothermal system, to place some limits on the origin of geothermal fluids and reservoir carbon, the fluid recharge area, physical-chemical environment of hydrothermal alteration, and relative permeability of the geothermal system. The similarity of hydrogen isotope compositions of local meteoric water and geothermal reservoir fluid indicate that the geothermal fluids are virtually entirely of surface derivation. An isotopically reasonable source area would be the Mineral Mountains directly to the east of the Roosevelt system. Hydrothermal calcite appears to be in isotopic equilibrium with the deep reservoir fluid. The deltaC/sup 13/ values of deep calcites and T- pH-f0/sub 2/ conditions of the reservoir defined by measured temperature, fluid chemistry, and alteration mineralogy fix the delta/sup 13/C value of the geothermal system to -5 to -6.5% (PDB). These values do not unambiguously define any one source or process, however. There is a relatively small increase in /sup 18/O of geothermal fluids relative to their cold surface water precursors and significant /sup 18/O depletion accompanying hydrothermal alteration of the granitic host rock. These isotopic shifts indicate a high ratio of geothermal fluid to altered rock for the geothermal system, implying relatively rapid (geologically) recirculation rates and significant permeability of the geothermal system.

• Research Organization: Utah Univ., Salt Lake City (USA). Dept. of Geology and Geophysics
• DOE Contract Number: AS07-76ID01601
• OSTI ID: 5911506
• Report Number(s): DOE/ID/01601-T3; ON: DE82003940
• Country of Publication: United States
• Language: English

Related Subjects

15 GEOTHERMAL ENERGY
150302* -- Geothermal Exploration & Exploration Technology-- Geochemical Techniques & Surveys
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ALKALINE EARTH METAL COMPOUNDS
CALCITE
CALCIUM CARBONATES
CALCIUM COMPOUNDS
CARBON 13
CARBON COMPOUNDS
CARBON ISOTOPES
CARBONATES
CHEMISTRY
EVEN-EVEN NUCLEI
EVEN-ODD NUCLEI
FLUIDS
GEOCHEMICAL SURVEYS
GEOCHEMISTRY
GEOTHERMAL FLUIDS
GRANITES
GROUND WATER
Geothermal Legacy
HYDROGEN COMPOUNDS
HYDROTHERMAL ALTERATION
IGNEOUS ROCKS
ISOTOPE RATIO
ISOTOPES
KGRA
LIGHT NUCLEI
METEORIC WATER
NORTH AMERICA
NUCLEI
ORIGIN
OXYGEN 18
OXYGEN COMPOUNDS
OXYGEN ISOTOPES
PERMEABILITY
PLUTONIC ROCKS
RECHARGE
ROCK-FLUID INTERACTIONS
ROCKS
ROCKY MOUNTAIN REGION
ROOSEVELT HOT SPRINGS
STABLE ISOTOPES
SURVEYS
USA
UTAH
WATER