What’s the mechanism? These quakes are relatively shallow, within <5-10 km, indicating crustal movements along strike- slip planes, whereas one should expect normal or thrust faulting and deeper foci if mantle slippage were the case. Besides, differentiation of mantle material in this regions has had a long time to isostasize.
I suspect these guys are just looking for grant money.
For about $200 Million Dollars even I can do an earthquake study, come up with a cool powerpoint presentation, get some hollyweird celebrities to say this is all caused by global warming and put some alphabet soup letters after my name so it all looks official.
“What’s the mechanism?”
Tectonic Setting of the August 2011 Virginia Earthquake
http://www.earth.northwestern.edu/people/seth/research/VA2011/
Eventually, rifting starts within a continent, and the cycle starts again. Often the new rifting starts near the site of the earlier rifting, because continents don’t heal well. The eastern U.S. is a nice example. The Appalachian Mountains formed in a continental collision that closed an earlier Atlantic Ocean about 300 million years ago. Since then, the present Atlantic Ocean opened during the past 200 million years. This process left lots of fossil faults, old weak zones where earthquakes can - and do - happen. The Virginia earthquake probably happened on one of these.