Seismostatistical Approach for Risk Evaluation of Seismicity from Geothermal Reservoirs

Abstract

Research into enabling technologies for risk assessment of larger magnitude seismic events from geothermal reservoirs has taken on an increased priority because they are considered as one of the most critical environmental burdens associated with geothermal development. In this study, we have applied a seismostatistical modeling method to microseismic data collected at two geothermal fields and have investigated its feasibility for risk assessment. Results from our study suggest that one of the parameters in the ETAS seismostatistical model, which has previously been interpreted to represent the occurrence rate of events triggered by external forcing, can in both our cases be correlated with the treatment/stimulation injection rate into each reservoir. These results demonstrate the feasibility of seismostatistical modeling in assessing the risks of felt earthquakes associated with various human operations in geothermal reservoirs, although further investigation and modeling of behavior of induced seismicity is required.