Recent Tectonic Stress Field, Active Faults and Geothermal Fields in China

Abstract

It is proposed that geothermal fields (hot water type) do not develop in the absence of active faulting. Such active faults are controlled by recent tectonic stress fields. Using the data of earthquake fault plane solutions, active faults and surface manifestations, a map shawing the recent tectonic stress field, and the location of active faults and geothermal fields in the P.R. China is presented. Data collected from 89 investigated prospects with geothermal manisfestations indicate that occurrence of geothermal fields is controlled by active faults and recent tectonic stress fields. About 15% of the prospects were found to be controlled by conjugate fracture faults, 68% of the prospects are controlled by tensional or tensional shear faults, (the angle between these faults and the of maximum compressive stress is less than 45, often both are parallel). Another 14% was found to be controlled by compressive shear faults (here the angle between these faults and the of maximum compressive stress is greater than 45 ) .