[Skywise]

http://earthquake.usgs.gov/earthquakes/e...72#summary

and a few aftershocks.

Looks like their under the hydrothermal mud volcanoes.

Brian

[Island Chris]

Also in or next to a geothermal energy field. The San Andreas fault proper, or something very close to it, comes through close to there. Focal mechanism is oblique normal (extensional).
Chris