Northern Sumatra Indonesia got hit by a 7.7 magnitude earthquake, but no serious damage or casualties have been reported.
The sumatra earthquake occured Wednesday at 3:15 p m April 17, 2010 125 miles WNW of Sibolga, Sumatra, Indonesdia, 135 miles SW of Medan, Sumatra, Indonesia, 320 miles W of Kuala Lumpur, Malaysia and NW of Jakarta, Java, Indonesia.
The U.S. Geological Survey gave the following tectonic summary:
The Banyak Islands, Sumatra Indonesia earthquake occured today as a result of thrust faulting on or near the subduction interface plate boundary between the Australia-India and Sunda plates. At the location of this earthquake, the Australia and India Plates move north-northeast with respect to the Sunda plate at a velocity of about 60-65 mm/year. On the basis of the currently available fault mechanism and earthquake depth, it is likely that this earthquake occurred along the plate interface.
The subduction zone surrounding the immediate region of this Sumatra indonesia earthquake last slipped during the Mw 8.6 earthquake of March 2005, and today's Sumatra Indonesia earthquake appears to have occurred within the rupture zone of that earthquake. Today's earthquake is the latest in a sequence of large ruptures along the Sunda megathrust, including two M 7.4 quakes beneath Simeulue 125 km to the north in 2002 and 2008; a M 9.1 earthquake that ruptured to within 125 km north of this quake in 2004; a M 8.5 375 km to the south in 2007; and a M 7.5 260 km to the south near Padang in 2009.
The USGS initially measured the Sumatra earthquake at 7.8 instead of 7.7 magnitude. The indonesia earthquake triggered a local tsunami warning which was canceled two hours later.
No damage or casualties have been reported in the Sumatra Indonesia due to the earthquake. But witnesses reported power blackouts in several parts of Aceh province and on Simeulue Island, west of Aceh.
Sumatra, Indonesia is the largest island in the country. A 9.1 magnitude earthquake struck off Aceh in December, 2004, triggering a historic tsunami that killed 226,000 people, VOA News reported.
Indonesia is located in the Pacific Ocean's so-called Ring of Fire, where the continental plates meet. This creates conditions for frequent earthquake and volcanoes from Asia to the American Pacific coasts.
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Floods Claim over 100 Lives in Rio de Janeiro, Brazil
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Weather & Natural Disaster Blogger, Cruyff