GEOTHERMAL EXPLORATION IN NORTHWESTERN NEVADA WITH HYMAP

Increased emphasis on the development of renewable energy sources has provided new opportunities in geothermal exploration using remote sensing tools. The purpose of this work was to employ hyperspectral remote sensing data sets for mapping unique geothermal identifiers to help site new potential sources and further our understanding of geologic controls on existing resource areas. More than 2000 km2 of 5 m Hymap data was acquired at Pyramid Lake Paiute reservation and 122 km2 of 3 m data was acquired at Brady-Desert Peak geothermal fields. Bradys is already producing power and Pyramid Lake Tribal Lands are adjacent to power producing facilities. Both regions show good potential for new or increased electricity generation. Both of these areas are located within 80 km north and east of Reno, Nevada. Hymap is flown aboard a small twin-engine aircraft between altitudes of 1500 and 4500 m above ground level with126 narrow contiguous channels that cover the VNIR and SWIR (0.45-2.5µm). A standard ENVI spectral hourglass approach was used to identify and remotely map gypsum, siliceous deposits, argillic alteration, vegetation anomalies and structurally controlled carbonate. These mineral maps were then validated with field and laboratory spectral measurements, in addition to X-ray diffraction analyses. Detailed field corroboration and integration of multiple data sets in GIS data base outline regions of the highest potential. Our results led to new structural interpretations and have helped to focus exploration and drilling efforts for new geothermal resources.