Le Pentagone et les parcs nationaux (dont le National Mall) sont fermés.
"The magnitude 5.9 earthquake, based in Mineral, Va., according to the U.S. Geological Survey, was likely caused by a release of stress from the earth’s crust, said University of Toronto geologist Andrew Miall.
The tremors were probably a result of a “crustal stretching” that began about 200 million years ago, when North America first began to separate from Europe and Africa, Miall told The Huffington Post Canada.
“Earthquakes on the east coast or the eastern margin of North America including well inland in places like Toronto are related to very, very old fractures in the earth’s crust that are releasing stress that in many cases have been stored there for many years,” he said. “This crustal stretching is related to the opening of the Atlantic Ocean...and that’s still going on.”
When this release of stress occurs, it causes a minor to moderate earthquake — which can be felt over hundreds of kilometres, he said.
“We feel them in Toronto even though the epicentre is often in Ohio, Indiana or somewhere down in the Ottawa-St. Lawrence Valley,” he said.
Though a tremor of the magnitude recorded in Virgina can do damage in the immediate vicinity, Miall said that this type of quake “doesn’t foretell anything worse in the future,” adding that “these are usually one-offs.”"
http://www.huffingtonpost.ca/2011/08/23/earthquake_n_934239.html#s336750&title=donnamc
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