Scientists Pinpoint Great-Earthquake Hot Spots
December 5, 2012 in Preparedness
The world’s largest earthquakes occur at subduction zones – locations where a tectonic plate slips under another. But where along these extended subduction areas are great earthquakes most likely to happen? Scientists have now found that regions where ‘scars’ on the seafloor, called fracture zones, meet subduction areas are at higher risk of generating powerful earthquakes. The results are published today in Solid Earth, an Open Access journal of the European Geosciences Union.
[Fracture zones location example]
“We find that 87% of the 15 largest (8.6 magnitude or higher) and half of the 50 largest (8.4 magnitude or higher) earthquakes of the past century are associated with intersection regions between oceanic fracture zones and subduction zones,” says Dietmar Müller, researcher at the University of Sydney in Australia and lead author of the Solid Earth paper. The connection is less striking for smaller earthquakes.
Powerful earthquakes related to these intersection regions include the destructive 2011 Tohoku-Oki and 2004 Sumatra events.
“If the association we found were due to a random data distribution, only about 25% of great subduction earthquakes should coincide with these special tectonic environments. Therefore, we can rule out that the link we found is just due to chance,” he adds.
Read more at:http://phys.org