Whoa, that was intense! I just experienced a long and intense earthquake here in DC!
The USGS reports the following:
Magnitude 5.8 (Preliminary magnitude -- update expected within 15 minutes)
Date-Time
Tuesday, August 23, 2011 at 17:51:03 UTC
Tuesday, August 23, 2011 at 01:51:03 PM at epicenter
Location 37.875°N, 77.908°W
Depth 6 km (3.7 miles) set by location program
Region VIRGINIA
Distances
15 km (9 miles) S (179°) from Mineral, VA
18 km (12 miles) SSE (154°) from Louisa, VA
26 km (16 miles) ENE (58°) from Columbia, VA
54 km (34 miles) NW (314°) from Richmond, VA
139 km (87 miles) SW (214°) from Washington, DC
Location Uncertainty Error estimate not available
Parameters NST= 17, Nph= 17, Dmin=59.5 km, Rmss=0.33 sec, Gp=173°,
M-type="moment" magnitude from initial P wave (tsuboi method) (Mi/Mwp), Version=1
Source
West Coast and Alaska Tsunami Warning Center/NOAA/NWS
Event ID at00lqe6x3
It was the second earthquake I’d felt, but the first earthquake, though closer to Bethesda, was much smaller.
UPDATE: There’s been a couple aftershocks, too - one was small but the second one was strong enough to feel in Bethesda @ 4.2.
UPDATE 2: There was another smaller aftershock last night. The dampening pattern suggests to me, though I am no seismologist, that things are settling down. Good!
Thankfully the building I work at in Washington, D.C. has been inspected and is safe to return to. The problem with even a small quake on the east coast is that the buildings are older and not at all designed to withstand substantial tremors. Apparently, brick buildings are especially vulnerable because they can crumble and topple to the ground. Gulp! The buildings I work and live in are both made of brick…