Devastation In Chile Amplified By 1960 Magnitude 9.5 Quake
Geologists at the Woods Hole Oceanographic Institution (WHOI) say the massive, 8.8-magnitude earthquake that struck Chile last week occurred in an offshore zone that was under increased stress caused by a 1960 magnitude 9.5 earthquake. Some 300-500 times more powerful than the magnitude 7.0 quake in Haiti Jan. 12, the earthquake ruptured at the boundary between the Nazca and South American tectonic plates. The temblor was triggered when the "subducting" Nazca plate was thrust under the South American plate, uplifting a large patch of the seafloor and prompting tsunami warnings throughout the Pacific Ocean. The two plates are converging at a rate of 80 mm per year, says WHOI geologist Jian Lin, "which is one of the fastest rates on Earth." read more