The United States Geological Survey recorded a Magnitude 3.8 Earthquake at a depth of 7.8 km in Mineral County in western Nevada, slightly after 4.10 pm local time on Friday 25 April 2014 (slightly after 0.10 am on Saturday 26 April, GMT). There are no reports of any damage or injuries associated with this quake, but it was felt across much of Mineral County.
The approximate location of the 25 April 2014 Mineral County Earthquake. Google Maps.
Nevada is a zone of active mountain orogeny (mountain growth), fueled by the subduction zone on the American West Coast. The state is criss-crossed by faults associated with its many growing mountain ranges, which form part of the Rockies. The rocks of the North American lithosphere are being pushed to the east by seafloor spreading beneath the Pacific and to the west by seafloor spreading beneath the Atlantic. This results in folding and upthrust within the plate, principally in the Rocky Mountains, which run along the western margin of the North American Plate, close to the subduction and fault zones of the continent's west coast. This folding and thrusting leads to frequent Earthquakes throughout the Rocky Mountain region, with Nevada being one of America's most quake-prone states.
Witness accounts of quakes can help geologists to understand these events and the rock structures that cause them. If you felt this quake (or if you wee in the area but did not, which is also useful information) you can report it to the USGS here.
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