At least two large earthquakes struck off the west coast of northern Sumatra today, spurring a tsunami warning in the Indian Ocean.
* According to the U.S. Geological Survey, the first quake was 8.6 in magnitude and struck at 2:38 p.m. about 229 miles west of Sinabang in the northernmost Sumatran province of Aceh.
* The quake had a depth of about 13 miles and according to USGS fault maps, was located just west of the large plate boundary between the Australian plate and the Eurasian plate.
* According to the USGS a second quake measuring 8.2 in magnitude struck about two hours later. It was about nine miles deep and slightly farther southwest of the first quake.
* The Pacific Tsunami Warning Center issued a tsunami watch after the earthquakes. The watch statement said that based on sea level readings a tsunami might have been generated and coastal areas throughout the Indian Ocean were under a watch. The alert was later canceled.
* According to Earthquake-Report.com, residents all over Indonesia felt the shaking. The site received reports from many locations, including Malaysia, India, Bangalore, Vietnam, Sri Lanka and Thailand.
* Earthquake-Report.com reported electricity in the Aceh is down and streets have been jammed as residents have sought high ground in anticipation of a tsunami.
* The location of the quakes was similar to the 9.1 magnitude megathrust quake of 2004. That quake generated a devastating tsunami and more than 220,000 people died.
Tammy Lee Morris is certified as a Community Emergency Response Team (CERT) member and is a trained Skywarn Storm Spotter through the National Weather Service. She has received interpretive training regarding the New Madrid Seismic Zone through EarthScope -- a program of the National Science Foundation. She researches and writes about emergency preparedness, earthquakes, volcanoes, tornadoes, weather and other natural phenomena.
- tsunami warning