More Small Quakes Shake Sonoma County
THE GEYSERS (BCN) - The U.S. Geological Survey reported three earthquakes with a preliminary magnitude of 2.0 or larger struck Wednesday morning in Sonoma County.
The largest of the three quakes shook an area near the Geysers at 3:55 a.m., according to the USGS, and had a preliminary magnitude of 2.5 and a depth of 2.1 miles. Eight minutes later, a quake with a preliminary magnitude of 2.3 and depth of 1.1 miles struck the same area.
The first tremor shook the area at 12:43 a.m. That earthquake had a preliminary magnitude of 2.1 and a depth of 1.7 miles.
The epicenter was located one mile northwest of The Geysers and 11 miles east of Cloverdale, according to the USGS.
In the past seven days, 21 earthquakes of magnitude 2.0 or larger have occurred around The Geysers, with seven of those occurring within the past 24 hours.
The Geysers is the largest single geothermal field in the world, according to the U.S. Department of Energy, and the region experiences constant seismic events between 0.5 and 3.0 on the Richter scale.
Deep-well injection at the site, which the Department of Energy says is necessary for the extended and sustained production of geothermal resources at the site, is believed to fuel the region's seismicity.
The largest event recorded in The Geysers field was a magnitude 4.6 quake in 1973, according to the Department of Energy.
There are 22 active geothermal plants in the region that produce roughly 950 megawatts of power, or enough for about 950,000 homes.
