6.0 magnitude earthquake latest in a convulsion of strong tremors rattling dangerous region of Philippines
November 30, 2011–PHILIPPINES–A 5.0 and a 6.0 magnitude earthquake struck off the west coast of the Philippines along the Manila Trench. A 5.0 magnitude aftershock followed. The Manila Trench is an ocean trench in the South China Sea, west of the Philippines. It reaches a depth of about 5,400 m, in contrast with the average depth of the South China Sea of about 1,500 m. It is created by subduction, in which the Eurasian Plate is subducting under the Philippine Mobile Belt. The Manila Trench is associated with frequent earthquakes, and the plate movements which give rise to it are also responsible for the arc of volcanoes on the west side of the Philippine island of Luzon, including Mount Pinatubo which experienced a very violent VEI 6 Plinian eruption in 1991. It was the second largest volcanic eruption recorded in the 20th century.A 7.7 magnitude earthquake near Luzon in 1990 is believed to have been the trigger that set Pinatubo off.