First posted at 2:04pm] According to the U.S. Geological Survey, a 5.8 magnitude earthquake hits outside of Richmond, VA, at 1:51 p.m. The quake was felt in downtown Asheville. More on this story as it develops.
We’ll be following the news at #avlquake on Twitter, and updating.
Red square means within the past hour. URL: http://earthquake.usgs.gov/earthquakes/recenteqsus/
Thin red (pink) lines are known hazardous faults and fault zones. White lines are roads.
Here’s the USGS shakemap of the epicenter (http://earthquake.usgs.gov/earthquakes/shakemap/global/shake/c0005ild/ )
From the USGS site
Where are the Fault Lines in the United States East of the Rocky Mountains?
…fault lines are not a particularly reliable guide to earthquakes or earthquake hazards east of the Rockies. The earthquakes themselves are the best guide.
Faults are different from fault lines. A fault is a three-dimensional surface within the planet Earth. At the fault, rocks have broken. The rocks on one side of the fault have moved past the rocks on the other side. In contrast, a fault line is a line that stretches along the ground. The fault line is where the fault cuts the Earth’s surface. Faults come in all sizes, from small ones whose short fault lines you can see in a single road cut, to huge faults whose long fault lines can be seen best in pictures taken from orbiting satellites. Any particular block of the Earth has room inside for more small faults than big ones, so most faults are small. On continents, faults are everywhere, of all sizes, and they formed at many different times during the Earth’s long history.
The largest and most important faults in each state are usually shown on the state’s geologic map. A geologic map shows the locations of rocks of different kinds and ages. Because the geologic map shows the rocks that are exposed at ground level, the map also shows fault lines. However, many faults are entirely buried and do not reach ground level. Therefore, these buried faults have no fault lines, and they are usually not shown on geologic maps. If a buried fault is known at all, information about it is usually published in technical articles in geological journals.
From the USGS page for EHP Quaternary Faults
For information about the Southern Appalachian Cooperative Seismic Network, download this PDF document
The Virginia Tech seismic network operates in conjunction with other regional networks in the
ANSS mid-America region to collect high-quality seismic data in Virginia and adjacent parts of the
Appalachian region. Research objectives include earthquake monitoring to maintain continuity of
earthquake catalogs for seismic hazard assessment, studies of the seismotectonics of the region,
earthquake source studies, wave propagation, and the temporal/spatial behavior of seismicity. Outreach
objectives include development and maintenance of regional earthquake catalogs; and dissemination of
information to federal/state/local governments, the engineering community and the general public.