Geothermal Resources of the Western Arm of the Black Rock Desert, NorthwesternNevada: Part 2, Aqueous Geochemistry and Hydrology

摘要

The report describes the results of a study to examine the basic hydrologic andgeochemical data and to evaluate the validity of integrated conceptual models of the geothermal resources in the western arm of the Black Rock Desert, northern Great Basin. The most significant aspects of the study were: (1) The hydrologic connection, if any, between and among the various known thermal areas; (2) probable recharge paths to these thermal areas; and (3) controls on the aqueous geochemistry that can be deduced from information derived from springs and shallow wells. A multi-disciplinary approach was used, with emphasis on geochemistry and isotopic hydrology. Such an approach incorporates hydrologic, geochemical, and isotopic analyses and, thus, constrains conceptual heat-and mass-flow models more effectively than a limited study. The study was confined to the western arm of the Black Rock Desert. This area provided an opportunity not only to examine the relations between the shallow nonthermal water and the deeper thermal water, but also to explore the relations among several shallow thermal areas. Data collection was limited primarily to shallow ground water. Geology and geophysics were discussed in a previous report (Schaefer and others, 1983).