The United States Geological Survey recorded a Magnitude 5.1 Earthquake at a depth of 22.6 km, roughly 10 km offshore of the Chilean City of Quintero in Valparaíso Province, slightly after 1.00 pm local time (slightly after 6.00 pm GMT) on Wednesday 30 April 2014. This is a fairly large quake, and was felt as far away as Santiago, 123 km to the southeast of the epicenter, but there are no reports of any damage or casualties.
The approximate location of the 30 April 2013 Quintero Earthquake. Google Maps.
Chile is located on the west coast of South America, which is also the convergent margin between the Nazca and South American Plates. The Nazca Plate is being subducted beneath the South American Plate and is sinking beneath the South American Plate. This is not a smooth process, the rocks of the two plates continuously stick together then, as the pressure builds up, break apart again, causing Earthquakes. As the Nazca Plate sinks deeper it is partially melted by the friction and the heat of the Earth's interior. Some of the melted material then rises up through the overlying South American Plate as magma, fueling the volcanoes of the Chilean Andes.
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