Tuesday, February 7, 2012

200th anniversary of shaking, rattling, and rolling in the Midwest.

Yeah, yeah, yeah....go to Google or most any other site today and you'll see that today's the 200th anniversary of Charles Dickens' birth. Or they'll talk about how the Beatles arrived in New York in 1964. But February 7, 1812 is actually known for something much bigger here in the United States, even if 99% of the population has no idea what that is.

Today is the 200th anniversary of the largest of the 1811-1812 earthquakes known as the New Madrid Earthquakes. It's also the day the Mississippi River "ran backwards" for three days or just several hours, depending on which historical account you believe.

Now, I grew up living in the New Madrid Seismic Zone (NMSZ) and the houses I lived in were all near or almost on the fault line itself. I remember growing up we'd see the chandeliers swaying during church services if a small tremor happened. You could always tell who wasn't originally from the area because they'd be the ones freaking-out about it while the rest of us just continued on as if nothing had happened. For years when I had friends over I explained to them that if the house felt like it was going up-and-down, that's because a heavy train was going by (we lived near the tracks). If it felt like someone was shaking the house back-and-forth, that was an earthquake. And if it sounded like a large truck had crashed outside and the back-and-forth shaking started, that's a bigger earthquake and to hold onto something!

I remember in 1990 everyone in Southeast Missouri was making earthquake kits and planning to sleep in their clothes -- with their shoes on, too -- from December 1st to December 5th because Dr. Iben Browning, a climatologist, and Dr. David Stewart, director of the Center for Earthquake Studies at Southeast Missouri State University in Cape Girardeau, Missouri, announced in the St. Louis Post-Dispatch that Dr. Browning's "prediction"of a magnitude 6.0-7.5 earthquake along the New Madrid Fault with the specific dates of December 2nd and 3rd to be of the highest risk. Many were suspect of Dr. Browning who had claimed to predict the Mount St. Helens eruption and the 1989 Loma Prieta earthquake that interrupted the World Series in San Francisco. When Dr. Stewart jumped on-board the prediction bandwagon, some felt that gave new validity to the prediction, but others (mostly scientists) didn't believe it. However, a 4.6 tremor near Cape Girardeau in September 1990 got the public in a panic. I remember sitting on the floor of my apartment that morning when it happened and the shaking was so intense that I couldn't stand up. Of course, my apartment was in the upper level of a really old house which shook like Jell-o even if a large truck drove by. We did end up with damages from the natural gas line to the furnace becoming separated in the shaking and a few knick-knacks knocked off the shelves. But other than that, it wasn't any worse than any others I'd weathered previously.

The national and international media picked up the story from the Associated Press and ran with it. There were news and documentary crews from around the world descending on the little town of New Madrid. For days you could barely move through the streets because of all of the satellite trucks and big-name press talking heads who wanted to be there when it happened. What mostly happened, though, was a lot of people interviewing each other. There was a news crew from Japan that was there to measure the differences between a Japanese quake and a "big one" from the NMSZ. Every major network and publication had someone "on the ground" ready to report. In hindsight, it was rather silly of them to do that. If they had read the accounts of the actual 1811-1812 earthquakes, they'd have known that approximately 1000 people died during them -- and that's only because the area was very sparsely populated back then and there were no official counts of how many Native Americans still lived in the area. So, just for the sake of a story, everyone decided it would be best to put their top people in a small area right next to the levee holding-back the Mississippi River and wait for the big disaster to occur.

It became one of the biggest non-events ever in media history. December 2nd and 3rd came and went and nothing happened. The media and disaster tourists packed-up their things and went home. The New Madrid Museum printed t-shirts about "surviving the big one" which made fun of the fiasco that happened in their town. Dr. Browning said there was a 50% chance of it happening -- but technically there's a 50% chance of it happening any day of the week! It either does or it doesn't! But that doesn't mean it won't again....

The "New Madrid Earthquake" began on December 16, 1811 at about 2 a.m. Another major tremor happened a few hours later that reportedly knocked people off their feet and the ground could be seen rolling with the seismic waves. Landslides even destroyed small towns. Large trees were snapped in two and huge cracks appeared in the surface of the ground with large sulfur pockets being opened to the air. Sand blows erupted and the scars from them can still be seen to this day in the fertile farmland that grows soybeans, cotton, corn, milo and rice. There wasn't a seismic scale back then, but from the reports of those who survived and the geographic evidence, it's estimated that the earthquake was approximately a magnitude 8.6.



The February 7, 1812 quake was the largest and is still presumed to possibly be one of the largest earthquakes in human history. It's estimated that it would have measured a magnitude 8.8 and reportedly rang church bells in Boston and caused bricks to fall from buildings in Cincinnati. Local diaries reported people watching others walking across open fields, then feeling the shaking, and then seeing the person walking disappear into the ground. The Mississippi River began to churn and large whirlpools were created. At this time, a portion of the riverbed rose and created a fluvial tsunami which gave rise to the reports of the Mighty Mississippi "running backwards." Large waterfalls were also created and river traffic was doomed as a reported 30 boats were thrown over the falls, killing all passengers aboard. Islands in the river were completely washed-over or simply subsided, never to be seen again. And in Tennessee, the Reelfoot Lake was created as a large mass of land subsided due to the shaking and river backflow filled-in the hole. Tourists today to Reelfoot Lake will enjoy the large bald cypress trees that have grown over the centuries in this shallow lake created by geological violence.

No one knows if or when another major earthquake will occur along the NMSZ. The first report I received this morning from the U.S. Geological Survey was for a 2.5 along the NMSZ not far from one of the places I lived. You wouldn't feel one that mild, but it still shows how active the zone is. And it's another reason I'm glad I moved away from that area -- I really didn't fancy having liquifaction from the groundwater coming up through the sandy soil and creating a nice quicksand that would cause my house to sink. Nor was I very thrilled about the idea of having to fend-off neighbors and strangers who didn't stay prepared for any disaster while trying to ensure my family still had plenty of the water, food, and other supplies we'd stockpiled.

It's actually quite sad, in my opinion at least, that even though there are areas conducting "Shake-out" drills at schools and government buildings today, they're really not saying why they need to have these drills and how important it is to be prepared. Everyone thinks that earthquakes are a "California problem" and no one else should worry. Well, when the next New Madrid Earthquake strikes, millions of people in large cities like St. Louis and Memphis along with millions of others in the U.S. will find out just how dangerous a quake in the Midwest can be. And the country will never be the same after that.

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