Wabash Fault Zone

Many friends that I asked didn't feel the second earthquake that we experienced yesterday because they were either walking or riding in a car at that time.

My young Grandson and his classmates felt it because they were sitting at their desk but their teacher was standing and moving around and didn't feel it. They alerted him and he told them that they could lie down on the floor if they wanted to, so they could feel the vibrations.

I heard on the radio that this was indeed a second earthquake and not an aftershock. This second shaking started as soft vibrations that built up to a 4.5 magnitude quake for only a couple of seconds and then returned to just soft vibrations that lasted quite a while. It hit at 11:14 a.m. according to the United States Geological Service.

The article below gives information about the area that we live in. We are a part of the Wabash Fault Zone, they don't know if this is related to the New Madrid Fault or not. The Wabash Fault runs almost parallel to the Wabash River in Southern Illinois and Indiana and could be a northern extension of the New Madrid Zone but that seems up for debate.

The article says that the reason the quakes in this area are so far reaching is because of our old bedrock that they compare to a bell that carries the seismic waves like sound for a longer distance than the California quakes reach.

California's bedrock is young and fractured, the waves do not carry as far, like a cracked bell wouldn't carry the sound waves as far. So California Earthquakes are more localized. Our bedrock carries these waves well over a thousand miles because of its age and rigidness.

The strongest quake produced by the Wabash Fault was a magnitude 5.3 in southern Illinois in 1968. The New Madrid fault zone produced quakes in 1811 and 1812 that reached an estimated magnitude of 7.0. The Wabash faults have the potential to do the same. Some experts say that the Wabash could produce a quake that could devastate the region.

Scientists say Midwest quakes poorly understood - Yahoo! News

A map of the area where yesterday's quakes were felt:
Yahoo Map Image

Lots of maps of the New Madrid and Wabash Valley seismic zones:
New Madrid and Wabash Valley seismic zones

Another Quake

We just had another shake up. I was wide awake this time, it happened at around 11:26 AM. I was on the phone with my daughter-in-law when it happened, didn't last long, just a few seconds but was strong enough to knock stuff off of my desk.

Earthquake

Wow! Strange to be woke up by an earthquake in Southern Indiana. There I was, sound asleep when the bed started shaking and everything in the room started rattling. I was drowsy and thought that I was in a horse trailer for some reason and something was shaking the trailer. It seemed like the horse trailer was rocking. It went on for a long time until I was finally wide awake and realized that I was in bed. It seemed to go on for a full minute but was probably more like 30 seconds. It all happened sometime between 5:30 and 6:00 this morning. When it stopped, my husband came into the room and asked if I felt it, I said that I had and he said that it had to be an earthquake.

The news has just said that it was a 5.4 magnitude, that was centered in East Central Illinois. They say that animals react to earthquakes but my house dog didn't even wake up and I didn't hear any of our outside animals make a sound either.

Someone on the radio just said that this was a shaker and not a rolling earthquake. That rolling earthquakes do more damage. The last earthquake that I experienced was a roller. I was actually on my knees, in a basement, on concrete in our Church prayer room when that one took place and I could feel the rolling under my knees. It felt like one knee would rise then fall before the other one would rise and fall.

Today is the 102nd Anniversary of the Great San Francisco Earthquake, how weird is that?