5.9 earthquake in Virginia

[EasternUSWX]

Felt that last one a bit around 1245 as well.

[Ian]

Seem to be feeling constant little shakes here in Dundalk.

Magma moving toward the surface?

[virginiamom]

Magma moving toward the surface?

Nah, probably just locusts preparing to break through and swarm. LOL

[A-L-E-X]

Hmmm what happened to that tsunami he was predicting?

An interesting coincidence.... 1944 has been used as an analog for Irene, well we had a 5.8 earthquake that summer too and it was NYS' biggest and was felt across a wide area. Back then we were worried about Germans, now it's terrorists-- some things never change lol.

This is pretty wild-- besides the hurricane, we also had a 5.8 earthquake that summer, centered in NY State!

http://en.wikipedia....sena_earthquake

he 1944 Cornwall-Massena earthquake occurred on Tuesday, September 5, 1944, at roughly 12:40am EST in Massena, New York. It was registered as a magnitude 5.8 on the Richter scale and was felt for a great distance. This area is part of the Saint Lawrence River Valley and the seismically active zone known as the Saint Lawrence rift system. The earthquake is the largest known in New York's recorded history.Contents [hide]

1 Damage

2 Epicenter

3 The WWII Scare

4 References

[edit]

Damage

The earthquake was felt as far away as New York City, Quebec City, Toronto, and Boston and caused roughly $2 million dollars in property damage. Several large aftershocks were felt in the general area, described as a low rumble followed by a loud bang.

In the village of Massena, New York, approximately 90 percent of its chimneys were destroyed or damaged, along with heavy damage to masonry structures. It was also reported that cracks appeared in the ground around the town of Hogansburg, located 10 miles east of Massena. There were also reports of wells that dried up, and a crack in a deep alluvium north of Massena Center oozed water and sand.

Damage to the city of Cornwall, Ontario, was heavier due to a denser population and its geological location; many structures foundations were built on sand. The Collegiate and Vocational School in the area received heavy damage from masonry work falling through the roof of the gymnasium.

[edit]

Epicenter

The epicenter is located in the vicinity of Massena Center, a small hamlet located 3.5 miles east of the village of Massena. Research was taken from inspecting the local graveyards which had seen damage done in the form of headstones rotating on their foundations.

In the city of Cornwall, the French Cemetery, Saint Columban's Cemetery and Woodlawn Cemetery were inspected and found that the headstones had turned counter-clockwise. In the town of Massena, Calvary Cemetery and Massena Center Cemetery were inspected and found the headstones had turned clockwise. Its epicenter was determined to have been located in the hamlet of Massena Center due to the greater damage of the hamlet itself and the severe rotation found in the cemetery. All chimneys received severe damage along with several reports of foundation damage.

[edit]

The WWII Scare

Many of the citizens of Massena who were woken by the earthquake evacuated their homes and scanned the skies for German planes believing that the Germans were attacking the ALCOA smelting plant located on the eastern end of the village.

[Isopycnic]

http://blogs.discovermagazine.com/badastronomy/2011/08/23/virginia-earthquake-waves-ripple-across-the-us/

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!

[jburns]

http://blogs.discove...-across-the-us/

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!

Good stuff. Thanks for posting it.

[turtlehurricane]

In retrospect, this shows how far we still have to go with earthquake forecasting. There are alot of quakes like this that are completely surprising, and a tad mysterious. Hopefully one day we'll understand what's at work.

[yoda]

4.5 earthquake just reported.. likely aftershock

http://earthquake.usgs.gov/earthquakes/recenteqsww/Quakes/usc0005jg1.html#details

[turtlehurricane]

4.5 earthquake just reported.. likely aftershock

http://earthquake.usgs.gov/earthquakes/recenteqsww/Quakes/usc0005jg1.html#details

My friend in DC just posted about it on FB, sounds like another good shock.

[EasternUSWX]

Felt some jiggling up here too. I felt it and went to USGS immediately.

[AlexD]

Did not feel the aftershock.

[TUweathermanDD]

Felt it for sure here in Dundalk, computer shook a little.

[EasternUSWX]

[Dunkman]

I felt something ever so slight here, figured it was a plane but checked USGS anyway.

[Ian]

In retrospect, this shows how far we still have to go with earthquake forecasting. There are alot of quakes like this that are completely surprising, and a tad mysterious. Hopefully one day we'll understand what's at work.

"we" know basically nothing about earthquake forecasting

[LMolineuxLM1]

I thought i was fooken going nuts here, i felt it and was like wtf, are my nerves acting up from kinda being shaken from the bigger 5.9 earlier, now feeling this last aftershock, i quickly checked the USGS and saw it and then seen it on facebook as well. WTF ya know.

[marsman]

Curious as to how many people have damage to their homes they don't know about. I'm betting Irene's rains will reveal many cracks and openings no one knew was there. The real pain may come when filing an insurance claim.

The Insurance companies are going to have a mess on their hands with Irene as it is. I don't know where earthquake coverage comes in to play or if anyone even has it on the east coast. I don't have it on my home in CO, although it was an option.

[The Dude]

In retrospect, this shows how far we still have to go with earthquake forecasting. There are alot of quakes like this that are completely surprising, and a tad mysterious. Hopefully one day we'll understand what's at work.

In retrospect? You needed this earthquake to figure that out?

[Plokoon111]

I could of swore I woke up from the strangest reason. It might of been from the shock.

[Don Cherry's Jacket]

"we" know basically nothing about earthquake forecasting

This is true. Geologists have tried looking for patterns, and they have developed some decent indicators for figuring out increased risk, but not actual predictions, along the ring of fire and other contintental plate faults, but it is still a large crap shoot. One thing that's interesting is that there is a sort of "earthquake season", essentially late summer/fall, when they are more common, but they still happen at any time. One of the bigger ones in California (Northridge, 94) was in January. There's also some evidence that they are slightly more common very erarly or very late (theory being something about cooling/heating helping to trigger the actual release), but ours happened in the middle of the day and this aftershock in the middle of the night. That "they can happen without warning" feature really scares some people, as compared to a snow storm or a hurricane. But, I will say that I rather like that part of them. I don't have to run to the store to buy milk and toilet paper before, or shovel it after (unless something falls).

[hm8]

Thought this was pretty cool:

http://boingboing.net/2011/08/25/animated-map-of-va-earthquake-tweets-august-23-2011.html

[A-L-E-X]

This is true. Geologists have tried looking for patterns, and they have developed some decent indicators for figuring out increased risk, but not actual predictions, along the ring of fire and other contintental plate faults, but it is still a large crap shoot. One thing that's interesting is that there is a sort of "earthquake season", essentially late summer/fall, when they are more common, but they still happen at any time. One of the bigger ones in California (Northridge, 94) was in January. There's also some evidence that they are slightly more common very erarly or very late (theory being something about cooling/heating helping to trigger the actual release), but ours happened in the middle of the day and this aftershock in the middle of the night. That "they can happen without warning" feature really scares some people, as compared to a snow storm or a hurricane. But, I will say that I rather like that part of them. I don't have to run to the store to buy milk and toilet paper before, or shovel it after (unless something falls).

There was some interesting researched published in Nature a couple months ago which illustrated a mechanism in which earthquakes cause changes in the local environment a few days before occurrence which might be fruitful in being able to predict them one day (it's in my sub forum but search is disabled so I will link it later.) Some animals may be able to detect these changes in advance-- for example, it was documented that Lemurs and Howler Monkeys at the National Zoo knew something was up (err, down lol) 15 min before it happened and before any of the other animals did. Research is currently being conducted to attempt to find out what's so different about them from other animals to allow them to do that. What the animals did before the 2004 Tsunami has also been noted.

[hm8]

More cool stuff here...apparently news spread through twitter and text messages about the earthquake faster then the seismic waves....so we CAN predict earthquakes (with a  few seconds of lead time)!

http://blog.xkcd.com/2011/08/24/earthquakes/

[Don Cherry's Jacket]

There was some interesting researched published in Nature a couple months ago which illustrated a mechanism in which earthquakes cause changes in the local environment a few days before occurrence which might be fruitful in being able to predict them one day (it's in my sub forum but search is disabled so I will link it later.) Some animals may be able to detect these changes in advance-- for example, it was documented that Lemurs and Howler Monkeys at the National Zoo knew something was up (err, down lol) 15 min before it happened and before any of the other animals did. Research is currently being conducted to attempt to find out what's so different about them from other animals to allow them to do that. What the animals did before the 2004 Tsunami has also been noted.

Which is your sub-form, sounds interesting. Anecdotally, I remember while growing up in CA, I was out at dawn (paper boy), and was listening to the birds and dogs do their normal morning noises, and then it suddenly got very quiet, and then there was a quake. Less a 15 minute prediction than (most likely) reaction to detecting the sounds or vibrations of the quake before noticable to humans.

[CharlesLS]

More cool stuff here...apparently news spread through twitter and text messages about the earthquake faster then the seismic waves....so we CAN predict earthquakes (with a  few seconds of lead time)!

http://blog.xkcd.com...24/earthquakes/

We have a similar system in Japan - earthquakes move a few km/s in the ground, so a combination of a sensor network and the speed of light means my phone + GPS will warn me when a major tremor is expected to reach me. For a very nearby major quake it arrives late, but for something further away I'll get between a few seconds and a minute or two of notice. Even a few seconds is valuable, since it means I won't be caught, say, carrying heavy furniture down a set of stairs when one hits, and also means I won't be confused about what's going on.

[A-L-E-X]

Which is your sub-form, sounds interesting. Anecdotally, I remember while growing up in CA, I was out at dawn (paper boy), and was listening to the birds and dogs do their normal morning noises, and then it suddenly got very quiet, and then there was a quake. Less a 15 minute prediction than (most likely) reaction to detecting the sounds or vibrations of the quake before noticable to humans.

It's in off topic. I'll link the Nature article as soon as search functions are re-enabled. How strong was the quake you experienced? The two CA quakes that I remember clearly were the one in 89 and the one in 94.

[The Dude]

We have a similar system in Japan - earthquakes move a few km/s in the ground, so a combination of a sensor network and the speed of light means my phone + GPS will warn me when a major tremor is expected to reach me. For a very nearby major quake it arrives late, but for something further away I'll get between a few seconds and a minute or two of notice. Even a few seconds is valuable, since it means I won't be caught, say, carrying heavy furniture down a set of stairs when one hits, and also means I won't be confused about what's going on.

What are you doing checking twitter while carrying heavy furniture??

[Don Cherry's Jacket]

It's in off topic. I'll link the Nature article as soon as search functions are re-enabled. How strong was the quake you experienced? The two CA quakes that I remember clearly were the one in 89 and the one in 94.

I was in the 89. That was ugly. My sister was in 94. I was also in a 8 in 1987 or 1988 while hiking, that pummeled a small town call Bishop. And a bunch of other 5s and 6s in San Diego (where I grew up) and San Francisco (where I lived for 10 years before moving the DMV). We'll chat about this later, after Irene, but in my experience each one is different in terms of the shake action, some roll, some bounce, some just rattle.

[Indystorm]

Back from vacation in eastern OH and want to report that I was sitting at a nature center window at Lowe-Volk nature center between Mansfield and Bucyrus and felt the initial quake. Thought some workers had dropped something, but then social media and the receptionist started talking about the earthquake. Nice surprise addition to the trip.