An earthquake of magnitude 8.6 (M8.6) struck off the northern coast of Sumatra in the early hours of April 11, 2012, triggering a tsunami warning across the Indian Ocean: the NOAA’s Pacific Tsunami Warning Center alerted agencies to the fact that ‘earthquakes of this size have the potential to generate a widespread destructive tsunami that can affect coastlines across the entire Indian Ocean basin.’
The ‘quake is the largest to have occurred in 2012, and is significant even in Indonesia, which is prone to damaging major earthquakes. Preliminary information from the United States Geological Survey (USGS) indicates that it occurred at a depth of around 20 miles, with an epicentre approximately 260 miles from the town of Banda Aceh, which was devastated by the Boxing Day earthquake of 2004. It was followed by a number of aftershocks which included a second massive tremor which was initially reported as M8.2.
Major Earthquakes in Sumatra
Indonesia is rarely out of the news as far as earthquakes go, and is regularly struck by some of the world’s largest and most damaging tremors. Most notably, the M9.1 Boxing Day earthquake of 2004 cost almost a quarter of a million lives. April 2012’s event is the fourth to occur with a magnitude of over M8 since the beginning of the 21st century.
As well as these earthquakes, there have been swarms of others which, though not on the scale of largest seen, are nevertheless significant and are capable of causing extensive damage and loss of life. USGS earthquake lists show that the country has experienced over 20 earthquakes of M7.0-M7.9 between 2000 and the present day.
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