the mineral, virginia earthquake lessons from a rare, shallow- depth, moderate - magnitude event in...
TRANSCRIPT
THE MINERAL, VIRGINIA EARTHQUAKE
Lessons From A Rare, Shallow-Depth, Moderate - Magnitude Event
in the Eastern United States
AUGUST 23, 2011
Dr. Walter Hays,
Global Alliance For Disaster Reduction
THE EARTHQUAKETHE EARTHQUAKE
1:51 PM ET
MINERAL, VIRGINIA: ABOUT 160 KM (100 MI) SW OF WASHINGTON, DC
MINERAL, VAMINERAL, VA
A TOWN OF 430 PEOPLE
Earthquakes are rare in the Eastern U.S. because the region is several hundred
miles away from the closest plate boundary, which is in the middle of the Atlantic Ocean.
Today’s shallow (1 km) earthquake was probably
generated by rupture of the Spotsylvania fault, an
ancient break in the Earth’s crust that is now a part of the North American plate.
THE M5.8 EARTHQUAKE OCCURRED AT 1:51 PM ON
AUGUST 23rd
THE M5.8 EARTHQUAKE OCCURRED AT 1:51 PM ON
AUGUST 23rd
The USGS downgraded the magnitude from M5.9 (tied for largest historic
quake in Virginia) to M5.8
ALTHOUGH A MODERATE EARTHQUAKE, THIS
EARTHQUAKE WAS THE LARGEST IN VIRGINIA SINCE
1897
ALTHOUGH A MODERATE EARTHQUAKE, THIS
EARTHQUAKE WAS THE LARGEST IN VIRGINIA SINCE
1897
WHAT HAPPENED FOLLOWING TODAY’S MODERATE
EARTHQUAKE
WHAT HAPPENED FOLLOWING TODAY’S MODERATE
EARTHQUAKE
Above all else, it was a WAKE-UP call!!!
No deaths, but with typical short- period effects close to the source and long-
period effects far from the source
Although the epicenter of the quake (and the source of the
seismic energy) was in Mineral, VA, the ground shaking was felt
as far north as Boston, New York, and Detroit, and as far
south as Atlanta.
NOTE: The rocks in the Eastern United States are old and cold,
which makes them more efficient in transmitting seismic energy from a M5.8 quake much farther than the young and hot
rocks in the Western United States.
MINERAL, VA: DAMAGE TO CITY HALL
MINERAL, VA: DAMAGE IN HOME
WASHINGTON DC: THE CAPITOL AND ALL GOVERNMENT BUILDINGS EVACUATED
WASHINGTON, DC: EVACUATION OF GOVERNMENT BUILDINGS
WASHINGTON, DC: EVACUEES ON PENNSYLVANIA AVE
WASHINGTON, DC: EVACUATION OF AUSTRIAN EMBASSEY
THE WASHINGTON MONUMENT HAD CRACKS NEAR THE TOP
WASHINGTON MONUMENT CLOSED
WASHINGTON CATHEDERAL: BROKEN SPIRE
WASHINGTON, DC: TRAFFIC GRID LOCK 2 HOURS AFTER EATHQUAKE
VIRGINIA: EVACUATION OF COLLEGE STUDENTS WHO JUST STARTED AGAIN
NEW YORK: EVACUATION OF BUSINESSES
The Governor of Virginia ordered a situation assessment to determine extent of damage
and needs.
US Capitol shut down for damage inspection by Capitol
Architect.
Many Virginia and Washington, DC schools closed for safety
inspections
Automatic safe shutdown of two nuclear power plants in
Virginia
WHAT DID WE LEARN FROM THE MINERAL
EARTHQUAKE?
WHAT DID WE LEARN FROM THE MINERAL
EARTHQUAKE?
1. Be ready to protect your capitol, your community, your
school, your business, --- and your people.
2. Be prepared for an act of terrorism, which is what many people thought that
the earthquake was (i.e., in some unknown way another
9/11 act of terrorism).
3. Be prepared for what can happen in a rare event---a moderate
earthquake that only happens every
century--- that can impact one-half of the
nation.
4. Be prepared for the situation when local
communication is disrupted and even shut down (i.e., when cell phones and the internet become useless immediately after a major
earthquake occurs).
5. Take actions to avert disaster by making the nation’s
communication network and its partnerships as broad and
deep as possible, encompassing and engaging
the appropriate local, community, state, Federal, and
international institutions.