— Wall Street Journal (@WSJ) September 17, 2015
A massive earthquake measuring 8.3 magnitude on Richter Scale hit Chile’s coast causing panic and severe damage to building triggering a tsunami warning that was issued toevacuate residents in the Andean nation’s coastal areas.
The tremors were felt as far as the other coast of Southern America and four aftershocks in the magnitude 6 rattled the area bringing fears of 2010 powerful earthquake in which hundreds were killed.
The evacuation along the 2,400 miles (3,900 kilometers) of Chile’s Pacific shore, from Puerto Aysen in the south to Arica in the north began with boats and fishermen were asked to return to safety, while the santiago airport was closed and road vehicles were pressed into service to evacuate people.
Damages were reported from the inland city of Illapel, about 175 miles (280 kilometers) north of Santiago and local televisions were showing the pictures of Illapel’s mayor, Denis Cortes who was seen giving instructions on evacuation process.
A woman had been killed in the city so far. The US Geological Survey first said the magnitude was of 7.9 but quickly changed it to 8.3. and aftershocks are reported in the range of 6 magnitude.
The timing of earthquake was 7:54 pm CLT (5:24 pm IST) and the quake was 7.4 miles (12 kilometers) below the surface. The tsunami was to arrive at 3 am local time.
In 1960, Chile experienced a 9.5 magnitude earthquake that killed more than 5,000 people. Meanwhile, New Zealand on the other coast of the ocean has warned its residents not to venture into the seas due to tsunami.
47km (29mi) SSW of Ovalle, Chile
58km (36mi) WSW of Monte Patria, Chile
80km (50mi) NNW of Illapel, Chile
102km (63mi) NNW of Salamanca, Chile
288km (179mi) NNW of Santiago, Chile
The South American arc extends over 7,000 km, from the Chilean margin triple junction offshore of southern Chile to its intersection with the Panama fracture zone, and it lies in the plate boundary between the subducting Nazca plate and the South America plate, where the oceanic crust and lithosphere of the Nazca plate begin their descent into the mantle beneath South America.
The convergence associated with this subduction process is responsible for the uplift of the Andes Mountains, and for the active volcanic chain present along much of this deformation front. Relative to a fixed South America plate, the Nazca plate moves slightly north of eastwards at a rate varying from approximately 80 mm/yr in the south to approximately 65 mm/yr in the north.
Most of the large earthquakes in South America are constrained to shallow depths of 0 to 70 km resulting from both crustal and interplate deformation, says USGS. Interplate earthquakes in this region are frequent and often large, and occur between the depths of approximately 10 and 60 km.
Since 1900, numerous magnitude 8 or larger earthquakes have occurred in this zone followed by devastating tsunamis, including the 1960 M9.5 earthquake in southern Chile, the largest instrumentally recorded earthquake in the world. Other notable shallow tsunami-generating earthquakes include the 1906 M8.5 earthquake near Esmeraldas, Ecuador, the 1922 M8.5 earthquake near Coquimbo, Chile, the 2001 M8.4 Arequipa, Peru earthquake, the 2007 M8.0 earthquake near Pisco, Peru, and the 2010 M8.8 Maule, Chile earthquake located just north of the 1960 event.
Most of these earthquakes occur adjacent to the bend in the coastline between Peru and Chile. The most recent large intermediate-depth earthquake in this region was the 2005 M7.8 Tarapaca, Chile earthquake. The 1994 Bolivian earthquake in northwestern Bolivia measuring 8.2 was an exception and it occurred at a depth of 631 km, which was until recently the largest deep-focus earthquake instrumentally recorded (superseded in May 2013 by a M8.3 earthquake 610 km beneath the Sea of Okhotsk, Russia), and was felt widely throughout South and North America.