According to the shake map above (click to enlarge – sorry about the crappy quality, but this is the original resolution), Washington DC is about 80 miles northeast of the epicenter of the 5.8 magnitude quake. It surprised me to hear that the quake caused officials to evacuate the Capitol and other government buildings. According to the color code, the DC area would have experienced “weak” to “light” shaking and no damage to structures.
As a former resident of a very seismically active area, I can attest that most of us who experienced that amount of shaking would simply have said “Hmmm – a little temblor.” And would go on with whatever we were doing. Some of us nerdy types would go to the USGS Earthquakes website to see the epicenter and magnitude. Maybe even look at the shake map.
5.8?
*yawn*
Hey, I’m from Californistan, O.K.?
I shrugged his one off, probably because I was pretty sure it was a quake and because I used to live in the Imperial Valley in California and experienced quite a few tremblers out that way. Still – it was concerning. My office shook quite a lot. The old buildings in NYC were never built to withstand earthquakes so that raised my concern even though my building was built to withstand a lot – they used to repair trains in it and had rails come into the building and elevators that brought the rail cars to different floors. Let me repeat, that is all in NYC. Several building in NYC were evacuated today. It was a pretty good jolt felt up here. I had to wonder if early reports of the epicenter in VA were correct, thinking it much closer to NYC, then learned that quakes on the east coast are felt with less attenuation and thus the force is spread over a larger area than west coast quakes because the bedrock up this way is not fractured by fault lines as it is out west. The western quakes do not transmit the energy as efficiently as do quakes in the east because the faults actually do not allow the energy to be transmitted as does the relatively solid and connected bedrock in the east. When you consider that, I guess you can understand how NYC shook, and how Washington, DC had buildings with structural damage.
All in all, it made for some excitement up our way. I am very happy it was not a bomb, as many had feared at first. Had it been one it would have been very big and very nasty.
All the best,
GB
I can understand Glenn’s point. Out west, plate tectonics are in play that can attenuate the propagation of “S” and “P” seismic waves. We (out west) tend to consider a 5.8 as “interesting” and discount the effects of a more efficient bedrock layer in the east.
The New Madrid quake in the nineteenth century (when the Mississippi river flowed backwards) may have been a manifestation of the bedrock efficiency.
By the way, did you guys see that there was a 5.3 (largest in 40 years) event in southern Colorado last night?
Hmmm… “Earthquakes in diverse places”, as the Bible says. Getting close to those end times, perhaps?
Add to the ‘quake inventory a 7.0 near the Amazon in Peru today. But that’s always been along the ring of fire and Earthquakes.