|
The 2010 Pichilemu earthquake (), also known as the Libertador O'Higgins earthquake, was a 6.9 MW intraplate earthquake that struck Chile's O'Higgins Region on 11 March 2010. The earthquake was centred northwest of the city of Pichilemu, according to the University of Chile Seismological Service. The earthquake was caused by increased regional stress arising from an earthquake on 27 February, centered offshore Maule Region, which was felt throughout central Chile. The 11 March earthquake was at first thought to be an aftershock from the 27 February event, but University of Chile Seismologist Jaime Campos identified it as an "independent earthquake". The Hawaii-based Pacific Tsunami Warning Center pointed out the possibility of local tsunamis within of the epicentre, although small, but violent waves were seen in the Pichilemu and Bucalemu area. One person was reported dead. At least eleven aftershocks immediately followed, causing panic throughout coastal towns between the Coquimbo and Los Lagos regions. The earthquake was specially destructive in the epicentre town, Pichilemu, capital of Cardenal Caro Province. The city hosts five National Monuments of Chile, of which two, the Agustín Ross Park and the Agustín Ross Cultural Centre, were seriously damaged by the earthquake. It also damaged the villages of La Aguada and Cardonal de Panilonco. Rancagua, the capital of O'Higgins Region, was also damaged, leading President Sebastián Piñera to declare a catastrophe state in O'Higgins Region. ==Background== Nearly all of the territory of Chile is subject to earthquakes, arising from strains in the subducting Nazca and South American Plates or shallow strike-slip faults. The subduction zone along the Chilean coast produced the most powerful earthquake ever recorded, the 1960 Valdivia earthquake. Some earthquakes which occurred near the epicentre of the 11 March 2010 event are the 1985 Algarrobo and Pichilemu (or Lago Rapel) earthquakes. On 27 February 2010, a strong earthquake, which reached a magnitude of 8.8 on the moment magnitude scale, hit central Chile. The earthquake occurred in the region of the plate boundary between the Nazca and South American plates, offshore Maule Region. The earthquake produced a tsunami which caused great damage in cities and towns along the Chilean coast; Pichilemu was "devastated" after the earthquake and tsunami struck. The 6.9 earthquake of 11 March 2010 occurred two weeks after the 27 February event. Chilean seismologists, including Sergio Barrientos from the University of Chile Seismological Service, were worried about the "absence of an earthquake around magnitude 7 following the February 27 quake."〔 〕 Two foreshocks of the 11 March event occurred on 5 March: one reached magnitude 5.7, and the other magnitude 5.2; both were felt between the Valparaíso and Maule regions. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「2010 Pichilemu earthquake」の詳細全文を読む スポンサード リンク
|