A Magnitude 4.2 Earthquake at a depth of 50 km occurred on the coast of northern Chile, 51 km south of the port of Antofagasta, slightly after 1.50 am local time (slightly after 5.50 am GMT) on Thursday 5 September 2013, according to the United States Geological Survey. This is a moderate Earthquake and occurred at a considerable depth in a remote area, so there are unlikely to have been any damage or casualties, though it may have been felt locally.
The approximate location of the 5 September 2013 northern Chile 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.
See also Magnitude 5.5 Earthquake in northeast Chile, Deep Magnitude 4.5 Earthquake in northwest Argentina, Evacuations ordered after activity on Copahue, Eruption on Mount Copahue and Earthquake off the coast of ChiloƩ Island, Chile.
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