Compound and Elemental Analysis At Coso Geothermal Area (1991)

GEOTHERMAL ENERGY

=====

Exploration Activity: Compound and Elemental Analysis At Coso Geothermal Area (1991)

Exploration Activity Details
Location	Coso Geothermal Area
Exploration Technique	Compound and Elemental Analysis
Activity Date	1991
Usefulness	useful
DOE-funding	Unknown

Exploration Basis

Determine the fluid origin by looking at variations in dissolved gas compositions of reservoir fluids

Notes

Gas concentrations and ratios in 110 analyses of geothermal fluids from 47 wells in the Coso geothermal system illustrate the complexity of this two-phase reservoir in its natural state. Two geographically distinct regions of single-phase (liquid) reservoir are present and possess distinctive gas and liquid compositions. Steam sampled from wells in the central and southwestern Coso reservoir is unusually enriched in both H₂S and H₂. Such a large enrichment in both a soluble and insoluble gas cannot be produced by boiling of any liquid yet observed in single-phase portions of the field. In agreement with an upflow-lateral mixing model for the Coso field, at least three end-member thermal fluids having distinct gas and liquid compositions appear to have interacted (through mixing, boiling and steam migration) to produce the observed natural state of the reservoir.

References

• Williams, A. E.; Copp, J. F.   (1 January 1991) Variations in dissolved gas compositions of reservoir fluids from the Coso geothermal field