Minutes after the quake, the director of the U.S. Geological Survey, Marcia McNutt -- who watched objects falling from the shelves in her office -- cautioned that the shaking might not be over. “What the concern is, of course, is that this is a foreshock. If it’s a foreshock, then the worse is yet to come.”
Earthquake Summary
Previous seismicity in the Central Virginia Seismic Zone has not been causally associated with mapped geologic faults. Previous, smaller, instrumentally recorded earthquakes from the Central Virginia Seismic Zone have had shallow focal depths (average depth about 8 km). They have had diverse focal mechanisms and have occurred over an area with length and width of about 120 km, rather than being aligned in a pattern that might suggest that they occurred on a single causative fault. Individual earthquakes within the Central Virginia Seismic Zone occur as the result of slip on faults that are much smaller than the overall dimensions of the zone. The dimensions of the individual fault that produced the 2011 August 23 earthquake will not be known until longer-term studies are done, but other earthquakes of similar magnitude typically involve slippage along fault segments that are 5 - 15 km long.
Earthquakes in the central and eastern U.S., although less frequent than in the western U.S., are typically felt over a much broader region. East of the Rockies, an earthquake can be felt over an area as much as ten times larger than a similar magnitude earthquake on the west coast. A magnitude 4.0 eastern U.S. earthquake typically can be felt at many places as far as 100 km (60 mi) from where it occurred, and it infrequently causes damage near its source. A magnitude 5.5 eastern U.S. earthquake usually can be felt as far as 500 km (300 mi) from where it occurred, and sometimes causes damage as far away as 40 km (25 mi).
I was very glad to have a friend- Mendy Tanner, who lives in Virginia -very near our missionary. She told me that she had just talked my missionary. They were all at a Zone Conference in the church building when the earthquake hit. They are all safe and accounted for.
The earthquake was felt as far north as NYC and Rhode Island- for rememberance here are a few pictures.
President Obama's golf game is interupted, he asks, Ya'll having a party of somethin?
From the missionary Moms group:
> Date: Tue, 23 Aug 2011 14:48:36 -0400> Subject: [LDSmmSEUS] Earthquake in VA
Just wanted you all to know your missionaries got a good shake up. I'm sure
they are all fine and will have fun stories to tell. It was a little scarywhen it was happening, but didn't last too long. Phone service is backed upso difficult to call or text in or out. But just wanted you to know that noinjuries have been reported or any damages. Epi- Center was south of Fredericksburg in Mineral, VA. 5.9. Bridges are being inspected, trains arebeing delayed and tunnels closed until inspected. Hope this helps and youdon't worry.-- Lia LeeRMM Elder Ryan Lee - Birmingham England Mission 1/07-1/09
