Source Characteristics of Micro-Earthquakes at the Northwest Geysers Geothermal Field, California

摘要

We investigate the source parameters of micro-earthquakes (M5.5), natural occurring tectonic earthquakes. Possible explanations for the high stress drop are, for example, fault re-strengthening by geochemical alteration or the fracturing of intact rock induced by the injection of cold water. This source information has implications for understanding the physics of faulting and for seismic potential assessment in areas of ongoing geothermal exploration.