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Swift
2012-Dec-06, 03:41 PM
From Laboratory Equipment Magazine (http://www.laboratoryequipment.com/news/2012/12/scientists-locate-great-earthquake-hot-spots?et_cid=2981263&et_rid=54636800&linkid=http%3a%2f%2fwww.laboratoryequipment.com%2f news%2f2012%2f12%2fscientists-locate-great-earthquake-hot-spots)


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 in Solid Earth, an Open Access journal of the European Geosciences Union (EGU).

“We find that 87 percent 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 Univ. of Sydney and lead author of the Solid Earth paper. The connection is less striking for smaller earthquakes.
I find it interesting that this connection is just being made now, but maybe it is taken this long to get a large enough dataset.

Ara Pacis
2012-Dec-07, 10:10 AM
I'm not exactly sure what they mean by "fracture zones". Maybe they just needed better resolution on bathymetry, which has been historically lacking.

dgavin
2012-Dec-13, 03:42 AM
Full paper can be viewed here. http://www.solid-earth.net/3/447/2012/se-3-447-2012.pdf

Basically from a quick browse through it, what it sounds like is that regions where a fault/frature zone on the oceanic crust, intersect with a subduction zone, are where Megathrust earthquakes originate around 87% of the time.

What it means is that the largest quakes, typically happen in area's that can be identified.