STORM2K

Probability of future earthquakes
The probability of magnitude 6.0 or greater in the near future is considered significant; a 90% chance of such an earthquake by 2040 has been given. In the June 23, 2005, issue of the journal "Nature", the odds of another 8.0 event within 50 years were estimated to be between 7 and 10 percent.

Because of the unconsolidated sediments which are a major part of the underlying geology of the Mississippi embayment, as well as the river sediments along the Mississippi and Ohio River valleys to the north and east (note the red fingers extending up these valleys in the image above), large quakes have the potential for more widespread damage than major quakes on the west coast.


Comparison: the 1895 Charleston, Missouri, earthquake in the New Madrid seismic zone with the 1994 Northridge, California, earthquake. Red indicates area of structural damage, yellow indicates area where shaking was felt.

Population of Major cities in danger:

- St. Louis, MO: (2006) 2,801,033
- Memphis, TN: (2006) 1,260,581
- Chicago, IL: (2006) 9,505,747
- Detroit, MI: (2006) 4,468,966
- Indianapolis, IN: (2006) 1,984,644

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Most of the time when we talk about natural disasters in the forum the conversation is mostly about hurricanes in the east and gulf coast. Tornadoes in the central US. Yellowstone supervolcano blowing its top. Earthquakes and tsunamis in the west coast, and many others. But we have never discussed the real possibility of a major disaster happening in the core of the United States that could have repercusions accross almost 2/3 of the country. I just wanted to know if anyone living in the danger area if you have any plan in case of a major earthquake in the area, or does you city have preparation plans. It's a real danger zone and there nothing that says that what happened in 1811 & 1812 won't happen again. The difference now is the temendous increase in population compared to back in the beginning of the 19th century.

Brooklyn, NY had an earthquake back in the late 1800s, which collapsed a few brick walls. Probably wasn't strong at all, by California standards, but cities with century old masonry buildings wouldn't need a huge earthquake to cause serious problems.



Another reason to live in Texas.

I'm just waiting for a quake here or in the Madrid Fault area. Ive felt one since ive been here, probability of another is probably low, but high enough to cause worry. Im glad I dont live in Memphis or CA.

I live just inside the lower right corner of the red zone on the map, but I don't find
myself sitting around worrying a lot about it. I guess it's similar to the attitude of
people who live around active volcanoes - it certainly could happen, but, there's too
much speculation on when. As far as having any real plans, I don't have any
beyong standing in a doorway and holding on to the door frame for dear life - IF I
happen to be inside when it hits!

~Annette~

There was a weak earthquake (4.6) centered about 60 miles west of Richmond in 2004, so a major earthquake centered in this area is not out of the realm of possibility. However, the fault system in this region is quite old, and most earthquakes that do occur are usually weak. Howard and Anne Arundel Counties in Maryland often have weak earthquakes from time to time.

Our biggest opportunity for a damaging earthquake would come from a New Madrid-strength quake somewhere in the western Ohio Valley.

I don't worry about one for around here. We did have a small earthquake in the early 1990's that I did feel.

The reason the earthquakes in CA are not felt in a widespread area is because of the numerous faults in CA. The seismic waves are stopped by the faults. In New Madrid, when an earthquake occurs on the fault (it is believe to an ancient fault or rift in or under the North American plate. . . I know, I need to stop watch Mega Disasters, but it the fault of writers' strike.), the seismic waves will be felt far away as New York and Montreal. There are no faults to stop the vibrations.

Mega Disasters (History Channel) was talking about sandblows that erupted from the cracks from the earth. The sand deep underneath the topsoil and ground undergo liquefaction (there is water underneath the sand). Using the sand blows that geologists found, they were able to date the San Madrid earthquakes. They think there were earthquakes in 300 AD, 900 AD, 1450 AD.

The earthquake created new lakes and drained others. The waters of the Mississippi went over their banks. If I lived upsteam or downstream (especially Louisiana) from the earthquake, I'd be worried that the earthquake would destroy the levees. In 1811 the earthquake temporarily changed the current of the river.

There is a pretty good book about the 1906 SF earthquake that has several chapters on the geology of the US and I think it starts with San Madrid and Charleston SC earthquakes. Here is the link to the audiobook

The name of the San Madrid fault is the Reelfoot Rift

Stephanie wrote:I don't worry about one for around here. We did have a small earthquake in the early 1990's that I did feel.

I guess no one told you about the fault lines under New York City. See Season 2 Episode 8 of Mega Disasters:

An earthquake in New York City may seem like the plot of a bad movie, but a magnitude 5 quake occurred in 1884 and could happen again. Two faults run under Manhattan Island, including the 125th Street Fault where the landscape dips and the subway crosses on an open bridge. Since skyscrapers are designed to withstand windspeeds of 100MPH, most would survive sans windows; however, mid-sized masonry structures would collapse. As well, buildings (including smaller skyscrapers) built on landfill in Battery Park are subject to soil liquefaction, tipping over entirely in a major earthquake.

Gee, THANKS lurker!

Nope, never saw any of those shows.

Never worried about it untill last year...


http://www.msnbc.msn.com/id/13119229/

I didn't before that near miss of Miami


I don't imagine that buildings here are all that earthquake proof. They are not really built to sway

Derek Ortt wrote:I didn't before that near miss of Miami


I don't imagine that buildings here are all that earthquake proof. They are not really built to sway

You'd think they would be because of Hurricanes.

Well, I suppose a meteorite might crash into the Gulf off HOU and cause a tsunami, but for the combination of low natural disaster risk and no state income tax, and a pleasant climate, with all four seasons, including a cold season, but with a cold season that usually has short outbreaks of cold between longer mild periods, and, again, no state income tax, SE Texas is about perfect.

Hmmm...I dont really feel concerned with a possible earthquake. There is a chance, but if it happens, it happens. Not much we can really do about it. I'm more "worried" about the Canary Islands sliding into the ocean than I am an earthquake.

brunota2003 wrote:Hmmm...I dont really feel concerned with a possible earthquake. There is a chance, but if it happens, it happens. Not much we can really do about it. I'm more "worried" about the Canary Islands sliding into the ocean than I am an earthquake.

I saw that one on TV. Imagine a tsunami hitting the entire East Coast from Maine to Miami...

Well, I am an earthquake watcher. I keep an eye on the New madrid reports. I remember the quake we had in Philly in the 70's, I was in grade school and it wasn't a big deal but we all felt it.

Now I don't worry about it, much, but I keep an eye on La Palma and also NYC-NYC is due for one from the fault that runs up there.

I have thought about it before a lot, but I've never really "worried" about it. There was a 4.7 here back in 2003 which I slept through. (Biggest quake to be centered in the state)

feederband wrote:Never worried about it untill last year...


http://www.msnbc.msn.com/id/13119229/

I remember that and I was sitting at my computer and swore the house and floor was moving for a few seconds. I thought ; no fricking way , not in Florida Then, it was all over the radio about the quake 150 miles offshore Western Florida

An earthquake has gotta be the disaster I would most be afraid of. That or a flood. In regards to this topic, all I say is thank goodness I'm out of Michigan and in Arizona, where we can't get them!

-Andrew92

Cincinnati checking in. We've had a few earthquakes over the past 2 or 3 decades that I recall. Do people here worry about them - for the most part, no. When one does occur, there's talk about a big one hitting someday (how we're overdue for one). But overall no there is no worry, no prep going on. Not like there is in CA for example. I do recall back in 1990 or 1991 a major earthquake was predicted for this region, in early Dec. that year. I want to say either Dec. 2 or Dec. 3. A widely known and well respected geologist came out and predicted that quake, on that date and staked his reputation on it. Some were worried. He cautioned people not to go in high rises, not to ride elevators and not to cross bridges. My oldest was in pre-school and her school was 5 miles away. I contemplated not sending her that day. My husband had a major laugh over that concern. He teased me something terrible. In the end I sent her, but shopped in the area near her school, just in case it hit and I couldn't get to her. Being around the corner, I knew I could walk if it hit.

Well, the quake never happened, as many know and I think this geologist lost a lot of respect for that prediction.

That date is long forgotten by most people. LOL

That pre-schooler is in college close to the New Madrid Fault and when I first mentioned if there's ever an earthquake (and was going to say, here's what you do....) I couldn't even finish my sentence. "An earthquake in Kentucky?"......LOL. Of course by now she's heard that they are at risk for a quake in the Western Kentucky region so she knows I'm not crazy but even there, I think most think it will happen in California before it happens in KY.

Mary