Magnitude 5.9 - VIRGINIA

[Ronan Kelly]

Magnitude 5.8 - VIRGINIA
2011 August 23 17:51:03 UTC
DetailsMapsTsunami Earthquake Details
This event has been reviewed by a seismologist.
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
http://earthquake.usgs.gov/earthquakes/recenteqsww/Quakes/at00lqe6x3.html

 

[Ronan Kelly]

Re: Magnitude 5.8 - VIRGINIA

Re: Magnitude 5.8 - VIRGINIA

Felt it here in Jersey - rattled the house for about 5 seconds.

 

[Ronan Kelly]

Re: Magnitude 5.8 - VIRGINIA

Re: Magnitude 5.8 - VIRGINIA

Update:

Earthquake Details
This event has been reviewed by a seismologist.
Magnitude 5.9
Date-Time Tuesday, August 23, 2011 at 17:51:03 UTC
Tuesday, August 23, 2011 at 01:51:03 PM at epicenter

Location 37.975?N, 77.969?W
Depth 1 km (~0.6 mile) (poorly constrained)
Region VIRGINIA
Distances 6 km (4 miles) SSE (152?) from Louisa, VA
6 km (4 miles) SW (236?) from Mineral, VA
26 km (16 miles) SE (133?) from Gordonsville, VA
66 km (41 miles) NW (318?) from Richmond, VA
134 km (83 miles) SW (219?) from Washington, DC

Location Uncertainty horizontal +/- 10.9 km (6.8 miles); depth +/- 7.4 km (4.6 miles)
Parameters NST=390, Nph=390, Dmin=57.9 km, Rmss=1.17 sec, Gp= 47?,
M-type=regional moment magnitude (Mw), Version=6
Source Magnitude: USGS NEIC (WDCS-D)
Location: USGS NEIC (WDCS-D)

Event ID usc0005ild
http://earthquake.usgs.gov/earthquakes/recenteqsww/Quakes/usc0005ild.html

 

[alert]

Re: Magnitude 5.8 - VIRGINIA

Re: Magnitude 5.8 - VIRGINIA

Felt it here in PA too. Walls and doors shook.

 

[Pathfinder]

Re: Magnitude 5.9 - VIRGINIA

Instrumental Intensity

<MAP name=Instrumental_Intensity_imap><AREA class=shakemapStation title="Station (CBN) PGA: 5.59 PGV: 2.84 N38.20 W77.37" href="stationlist.html#sCBN" shape=CIRCLE alt="Station (CBN) PGA: 5.59 PGV: 2.84 N38.20 W77.37" target=_blank coords=370,270,5 jQuery15106463340091721733="7"><AREA class=shakemapStation title="Station (SDMD) PGA: 1.87 PGV: 0.23 N39.41 W76.84" href="stationlist.html#sSDMD" shape=CIRCLE alt="Station (SDMD) PGA: 1.87 PGV: 0.23 N39.41 W76.84" target=_blank coords=434,86,5 jQuery15106463340091721733="8"><AREA class=shakemapStation title="Station Epicenter: N37.97 W77.97 M=5.9" href="javascript<b></b>:void(null)" shape=CIRCLE alt="Station Epicenter: N37.97 W77.97 M=5.9" target=_blank coords=299,305,7 jQuery15106463340091721733="9" name="quake"><AREA class=shakemapStation title="Station About Intensities" href="http://www.abag.ca.gov/bayarea/eqmaps/doc/mmi.html" shape=RECT alt="Station About Intensities" target=_blank coords=45,572,548,593 jQuery15106463340091721733="10" name="intensity"></MAP>Available Formats: JPG (143 kB) || PS (693 kB)

http://earthquake.usgs.gov/earthquakes/shakemap/global/shake/c0005ild/

 

[Pathfinder]

Re: Magnitude 5.9 - VIRGINIA

Quake strikes near Washington

<!--endclickprintinclude--><!--startclickprintexclude-->By the CNN Wire Staff<SCRIPT type=text/javascript>cnnAuthor = "By the CNN Wire Staff";</SCRIPT>
<SCRIPT type=text/javascript>if(location.hostname.indexOf( 'edition.' ) > -1) {document.write('August 23, 2011 -- Updated 1828 GMT (0228 HKT)');} else {document.write('August 23, 2011 2:28 p.m. EDT');}</SCRIPT>August 23, 2011 2:28 p.m. EDT
August 23, 2011 -- Updated 1828 GMT (0228 HKT)


Excerpt:
"It's one of the largest that we've had there," USGS seismologist Lucy Jones told CNN. Aftershocks were a concern, she said. "People should be expecting (them), especially over the next hour or two," she added.

She said that she would expect to see "significant damage" to old, brick buildings near the epicenter. "If you've already got some damage, you might want to stay outside," she said.

She also raised concern that water and gas lines may have been damaged.

Full text:
http://edition.cnn.com/2011/US/08/23/virginia.quake/

 

[Sally Furniss]

Re: Magnitude 5.9 - VIRGINIA

The North Anna Power Station, which has two nuclear reactors, is now using four diesel generators to maintain cooling operations. The plant automatically shut down in the wake of the earthquake

http://online.wsj.com/article/SB10001424053111903461304576526642400085456.html?mod=googlenews_wsj

 

[Sally Furniss]

Re: Magnitude 5.9 - VIRGINIA

East Coast earthquakes are far less common than in the West, but they tend to be felt over a broad area. That's because the crust is not as mangled and fractured, allowing seismic waves to travel without interruption.
"The waves are able to reverberate and travel pretty happily out for miles," said US Geological Survey seismologist Susan Hough.

http://www.stuff.co.nz/world/americas/5496905/Magnitude-5-8-quake-hits-US-East-Coast

 

[Emily]

Re: Magnitude 5.9 - VIRGINIA

Uploaded by TheBadAstronomer on Aug 23, 2011

Seismometers from the EarthScope project Transportable Array measured the up-and-down motion of the ground from the magnitude 5.9 earthquake that occurred in Virginia on August 23, 2011. You can see the waves move across the country! Red is upward motion; blue down. The height of the wave was only 22 microns!

Original data: http://www.iris.edu/spud/gmv/109962

Credit: Data from the TA network were made freely available as part of the EarthScope USArray facility supported by the National Science Foundation, Major Research Facility program under Cooperative Agreement EAR-0350030.

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http://www.vtnews.vt.edu/articles/2011/01/010611-engineering-greenearth.html

Assessing the seismic hazard of the central-Eastern United States

BLACKSBURG, Va., Jan. 6, 2011 – As the U.S. policy makers renew emphasis on the use of nuclear energy in their efforts to reduce the country’s oil dependence, other factors come into play. One concern of paramount importance is the seismic hazard at the site where nuclear reactors are located.

Russell A. Green, associate professor of civil and environmental engineering at Virginia Tech, spent five years as an earthquake engineer for the U.S. Defense Nuclear Facilities Safety Board in Washington, D.C., prior to becoming a university professor. Part of his responsibility at the safety board was to perform seismic safety analyses on the nation’s defense nuclear facilities.
[snip]
Unlike many places in the western U.S. where excavations can be used to determine the past movement on earthquake faults, in the central-eastern U.S. the locations of most faults are unknown and/or the faults are too deep to excavate. As a result, Green is concentrating his work on the development and validation of paleoliquefaction procedures. Soil liquefaction is the transition of soil from a solid to a liquefied state. Earthquakes are one cause of liquefaction, with the evidence of liquefaction often remaining in the soil profile for many thousands of years after the earthquake.

http://www.paleoseismicity.org/blog/2011/08/24/the-wednesday-centerfault-8-virginia-m5-8-earthquake/

The Wednesday Centerfault (8) – Virginia M5.8 Earthquake

Christoph Grützner

[snip]
From weak events it is known that there is certain seismic hazard, although not too much information is available. However, the epicentral region was a colored spot on the seismic hazard map and called the Central Virginia Seismic Zone. Paleoseismological studies are rare in that area – a lot of seismites have been found, but dating back to Ordovician to Permian times, when the Appalachian Orogeny took place. That’s a little too old for us. As far as I know, there haven’t been paleoseismological trenching studies in that area that proved holocene surface-rupturing earthquakes – does anyone know more?

http://blogs.agu.org/mountainbeltway/2011/08/23/the-mineral-va-earthquake-of-august-23-2011/
23 August 2011
The Mineral, VA earthquake of August 23, 2011 – UPDATED

Posted by Callan


(Callan Bentley is an assistant professor of geology at Northern Virginia Community College in Annandale, Virginia. )

 

[Emily]

Re: Magnitude 5.9 - VIRGINIA

A huge crane being used to repair earthquake damage to the Washington Cathedral collapsed without warning today, (though the article says there were wind gusts of 40-50 mph at the time.)

http://www.washingtonpost.com/blogs/post_now/post/crane-topples-at-national-cathedral-damages-buildings/2011/09/07/gIQA2LBU9J_blog.html

Posted at 02:45 PM ET, 09/07/2011
Crane topples at National Cathedral, comes down ‘like thunder’
By Patricia Sullivan and Theola Labbe-DeBose

A crane toppled at the National Cathedral this morning, sending its operator to the hospital, damaging two out-buildings and crushing four vehicles that belonged to contractors....

 

[Emily]

Re: Magnitude 5.9 - VIRGINIA

Including the crane operator, this makes 3 workers taken away from the Cathedral in ambulances in the past 2 days.

http://www.cbsnews.com/stories/2011/09/08/ap/business/main20103567.shtml
September 8, 2011 5:31 PM
2 injured dismantling crane at National Cathedral


http://www.reuters.com/article/2011/09/08/us-sept11-cathedral-idUSTRE7875QN20110908

National Cathedral moves September 11 events after accident
By Molly O'Toole

WASHINGTON | Thu Sep 8, 2011 2:06pm EDT

(Reuters) - The Washington National Cathedral has moved its events commemorating a decade since the September 11, 2001, attacks due to a crane crash on its grounds Wednesday, the Cathedral announced on Thursday.

Events are being moved to the John F. Kennedy Center for the Performing Arts.