| Abstract |
Domuyo Geothermal Field is located in the western slope of Domuyo volcanic complex in the Northwest of Neuquén Province, Patagonia, Argentina. This study is a summary of nine-month exploration works carried out by the government of Neuquén Province supported the National Energy Secretariat through Energy Sector Study Program (PESE by its initials in Spanish). The goals of the study were to outline the geothermal potential of the field and define drilling target for a further stage. A geological, geochemical and geophysical survey over an area of 220 km2, was carried out in the southwestern part of the Domuyo volcanic complex where many surface thermal manifestations are present. The geological survey includes a characterization of surface geology, mapping and sampling of geological units and regional and local structural geology with focus on the study area. Samplings of thermal manifestation from major thermal areas were carried out. Then chemical analysis of water and vapor, geothermometry and water classification were made. All the previously mentioned works were focused to define temperature of the reservoir and pattern of fluid circulation. The geophysics includes magnetotelluric (MT), TEM and gravity surveys. It´s important to mention that it is the first time that MT and TEM methods are employed in this geothermal field; while a widespread grid of gravity survey was made by JICA, 1984. Geophysical survey comprises the measurement of 91 MT stations, 40 TEM stations for correction of the static shift in magnetotelluric, and 130 gravity stations. This survey allowed to define zones of geophysical anomalies and its possible correlation with the geology and thermal anomalies detected in the previous thermal gradient holes made by JICA, 1984. Finally, a geo-scientific integration with all the geological, geochemical and geophysical information was made. Geothermal resource estimation with gradual decompression method and volumetric method were made and 3 drilling targets were defined. |