Relationship between water chemistry and sediment mineralogy in the Cerro Prieto geothermal field: a preliminary report

Conference · Thu Jan 01 04:00:00 EST 1981

OSTI ID:7369407

Valette-Silver, J N ^[1]; Thompson, J M; Ball, J W

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1. Univ. de Perpignan, France

The chemical compositions of waters collected from the Cerro Prieto geothermal production wells and hydrothermal emanations are different. Compared to the Cerro Prieto well waters, the surficial waters generally contain significantly less potassium, slightly less calcium and chloride, and significantly more magnesium and sulfate. In comparison to the unaltered sediments, the changes in the mineralogy of the altered sediments appear to be controlled by the type of emanation (well, spring, mud pot, geyser, fumarole, or cold pool). However, an increase in quartz and potassium feldspar percentages seems to be characteristic of the majority of the sediments in contact with geothermal fluids. Preliminary attempts to model the chemical processes occurring in the Cerro Prieto geothermal field using chemical equilibrium calculations are reported. For this purpose the chemical compositions of thermal waters (well and surficial emanation) were used as input data to make calculations with SOLMNEQ and WATEQ2 computer programs. Then the theoretical mineral composition of altered sediments was predicted and compared to the mineralogy actually observed in the solid samples.

• OSTI ID: 7369407
• Report Number(s): LBL-11967; CONF-810399-17; ON: DE82019261
• Country of Publication: United States
• Language: English

Related Subjects

15 GEOTHERMAL ENERGY
150302* -- Geothermal Exploration & Exploration Technology-- Geochemical Techniques & Surveys
CERRO PRIETO GEOTHERMAL FIELD
CHALCOGENIDES
CHEMICAL COMPOSITION
CHEMISTRY
COMPUTER CODES
FELDSPARS
GEOTHERMAL FIELDS
GEOTHERMAL WELLS
Geothermal Legacy
MINERALOGY
MINERALS
OXIDE MINERALS
OXIDES
OXYGEN COMPOUNDS
QUARTZ
SEDIMENTS
SILICON COMPOUNDS
SILICON OXIDES
THERMAL WATERS
WATER CHEMISTRY
WELLS