A Magnitude 5.7 Earthquake struck northeastern California on Wednesday 23 May 2013, according to the United States Geological Survey. The quake occurred at a depth of 11 km, to the east of Lake Almanor in Plumas County, roughly 275 km northwest of San Francisco. There are no reports of any damage or casualties, but the quake was apparently felt across much of northern California and in parts of western Nevada.
Map showing the location of the 23 May California Earthquake. Google Maps.
California is America's most Earthquake-prone state, being bisected by the San Andreas Fault, which is the boundary between the Pacific Plate, which is moving northeast, and North American Plate, which is moving southwest. This is actually nowhere near Plumas County, but the area is still affected by the tectonic movement; the two plates do not move smoothly past one-another, but rather continuously stick together than break apart, which has lead to a large number of smaller stress related faults that criss-cross the state.
Witness accounts can help geologists to understand Earthquakes and the underlying structures and processes that cause them. If you felt this quake (or were in the area but did not, which is also useful information) then you can report it to the United States Geological Survey here.
See also Los Angeles shaken by Earthquake, Magnitude 6.3 Earthquake off the coast of Baja California, Central California shaken by Earthquake, Earthquake swarm strikes southern California and Los Angeles shaken by Earthquake.
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