Micro-Earthquake At Coso Geothermal Area (1993-1994)

From Open Energy Information

Exploration Activity: Micro-Earthquake At Coso Geothermal Area (1993-1994)

Exploration Activity Details
Location Coso Geothermal Area
Exploration Technique Micro-Earthquake
Activity Date 1993 - 1994
Usefulness useful
DOE-funding Unknown

Exploration Basis
Multiplet analysis
Instances of microseismicity in seismic doublets which are co-located hypocenters that appear to have nearly identical waveforms were searched for. Using 1085 high-quality events from 1993 to 1994, they identified numerous doublets, some occurring within minutes of each other. The hypocentral data was subdivided into spatial clusters to reduce the computational burden and evaluated multiple cross-correlation pairs, assigning scores to each pair. The multiplets do not appear to be true repeating events; rather, they are clusters of small, nearly identically oriented ruptures, perhaps representing swarms of fractures activated by fluid-pressure fluctuations. Using the small volumes encompassing each multiplet, the fracture densities are estimated to measure between 0.02 and 0.4 m−1 and are largest near the injection wells.


Additional References