Seismic Characterization of the Newberry and Cooper Basin EGS Sites

Abstract

To aid in the seismic characterization of Engineered Geothermal Systems (EGS), we apply enhanced microearthquake detection and location techniques to two EGS systems: the Newberry EGS site and the Habanero EGS site in the Cooper Basin of South Australia. We apply the Matched Field Processing (MFP) seismic imaging technique to detect new seismic events using known discrete microearthquake sources. Events identified using MFP typically have smaller magnitudes or occur within the coda of a larger event. At the Newberry EGS site, 234 events were reported in the original catalog during a one year period including the first 2012 stimulation. MFP identified 202 additional events (an increase of over 85% more events). At the Cooper Basin Habanero EGS site, during a 12 day period including the start of the 2005 stimulation, 1238 events were identified in the original catalog and MFP identified an additional 123 events. This illustrates how MFP can be applied in conjunction with traditional earthquake detection techniques to enhance the official earthquake catalogs of EGS sites.