Induced Seismicity Patterns in the Paralana Geothermal Reservoir, South Australia

We are presenting the results of the analysis of seismicity induced by the first main stimulation of the geothermal reservoir at Paralana (south Australia) in July 2011. More than 7000 events were detected and processed automatically. A 3D velocity model was built from active seismic data and used to locate the events. Well-located microearthquakes were relocated using differential travel-times improved by waveform cross-correlation. Focal mechanisms of the four largest events (two Mw 2.4 and one 2.5) are all in thrust with a strike-slip component, consistent with the stress regime in the area.