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Commonwealth quake felt near and far

Earthquakes on the East Coast are rare, but they do happen, and they are often concentrated in certain areas. One of these pockets is the Central Virginia Seismic Zone, where Tuesday’s quake occurred. The bedrock in this zone has no major faults but is laced with small, ancient faults that occurred when the Appalachian Mountains were formed.

Commonwealth quake felt near and far
Sources: John Taber, seismologist and director of education and public outreach at the IRIS Consortium; USGS. Bonnie Berkowitz, Alberto Cuadra, Laris Karklis, Dan Keating, Todd Lindeman, Laura Stanton, Karen Yourish/The Washington Post. Published on August 23, 2011, 10:37 p.m.
 
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