"Mapping." . . "Thomas, R.P." . . "Geothermal Energy." . . "Geysers Geothermal Field." . . "Geothermal Fields." . . "Geysers Geothermal Field (Calif.)" . . "Heat Flow." . . "Geothermal Wells." . . "Rocks." . . "Physical Properties." . . . . . . . . . . . . . . . . . . . . . . . "Heat-flow mapping at the Geysers Geothermal Field"@en . . . "Pertinent data were compiled for 187 temperature-gradient holes in the vicinity of The Geysers Geothermal field. Terrain-correction techniques were applied to most of the temperature-gradient data, and a temperature-gradient map was constructed. Cutting samples from 16, deep, production wells were analyzed for thermal conductivity. From these samples, the mean thermal conductivities were determined for serpentinized ultramafic rock, greenstone, and graywacke. Then, a heat flow map was made. The temperature-gradient and heat-flow maps show that The Geysers Geothermal field is part of a very large, northwesterly-trending, thermal anomaly; the commercially productive portion of the field may be 100 km² in area. The rate that heat energy flows through the surface by thermal conduction is estimated at 1.79 x 10⁹MJ per year. The net heat energy loss from commercial production for 1983 is estimated at 180.14 x 10⁹MJ."@en . . . . . . . . . . "Wells." . . "Geothermal Gradients." . . "Thermodynamic Properties." . . "Igneous Rocks." . . . . "California Dept. of Conservation, Sacramento (USA). Div. of Oil and Gas" . . "Thermal Conductivity." . . "Metamorphic Rocks." . . "Temperature Gradients." . .