Massive magnitude 7.7 earthquake triggers tsunami that kills 113 in Indonesia
- October 26th, 2010 11:45 am ET
Ten foot tsunami waves caused by a massive earthquake swept across islands off the western coast of Indonesia killing at least 113 and leaving hundreds missing. The earthquake and tsunami add to the list of disasters in a 24 hour period that also includes a volcanic eruption.
The magnitude 7.7 earthquake struck at 9:42pm local time Monday night on the same fault that generated a magnitude 9.1 temblor in 2004 that killed 230,000. The quake was 12.8 miles below the surface and centered 150 miles west of Bengkulu, Sumatra, Indonesia or 500 miles west-northwest of Jakarta.
The tsunami appears to have struck hardest along the Mentawai island chain washing away hundreds of homes on Pagai and Silabu. The islands are a popular surfing spot accessible only by boat.
The latest death toll from the quake and tsunami stands at 113. Some reports place the number of missing as high as 500. Thousands were seeking shelter in emergency camps.
The nation is also dealing with an eruption of its most deadly volcano, Mount Merapi. The volcano started erupting early Tuesday morning depositing hot ash on residents and spurring fears that a larger eruption is imminent.
From the USGS:
The Pulau Pagai Selatan, Sumatra earthquake of October 25, 2010 occurred as a result of thrust faulting on or near the subduction interface plate boundary between the Australia and Sunda plates. At the location of this earthquake, the Australia Plate move north-northeast with respect to the Sunda plate at a velocity of approximately 57-69 mm/yr. On the basis of the currently available fault mechanism information and earthquake depth it is likely that this earthquake occurred along the plate interface. The subduction zone adjacent to the region of this event last slipped during the Mw 8.5 and 7.9 earthquakes of September 2007, and today’s event appears to have occurred near the rupture zones of those earthquakes. Today’s earthquake is the latest in a sequence of large ruptures along the Sunda megathrust, including a M 9.1 earthquake that ruptured to within 800 km north of this earthquake in 2004; a M 8.6 700 km to the north between Nias and Simeulue in 2005; and a M 7.5 300 km to the north near Padang in 2009. Today’s earthquake occurred near the southern edge of a Mw 8.7-8.9 rupture in 1797 and within the rupture area of a Mw 8.9-9.1 earthquake in 1833.