Re: Experts split over quake risk
- From: Jo Schaper <joschapern4ospam@xxxxxxxxxxxxxxxxx>
- Date: Thu, 15 Dec 2005 21:41:05 -0600
Man, what yahoo wrote that article?
By Eric Hand ST. LOUIS POST-DISPATCH 12/14/2005
The earth under the New Madrid Seismic Zone either isn't shifting or is barely shifting at all, say three independent university analyses of global positioning system stations stuck in the ground and monitored for a decade.
So the cataclysmic shifts of past earthquakes remain unexplained, the mechanism for future earthquakes still a mystery.
The results contradict a study by scientists at the University of Memphis. The study made headlines in June when it stated that two GPS stations on opposite sides of the Reelfoot fault - one of several in the New Madrid seismic area - had moved closer to each other at a rate that rivaled faults in California. The compression could coil up the faults for future earthquakes.
One of the detractors of that study, geophysicist Eric Calais of Purdue University, said their results were certainly a statistical anomaly, probably an instrumental error, and, regardless, not anywhere close to the motions of the San Andreas fault, which slips more than 10 times as fast as the two Reelfoot fault GPS stations seem to be creeping toward each other.
"It's not fair in a scientific paper to scare people with things like that," he said.
Michael Ellis, one of the University of Memphis authors, says his group was only trying to show that the motions are consistent with the level of seismic hazard that geologists have already established for New Madrid.
A debate among the groups was published today in the journal Nature.
In California, earthquakes are caused by the more predictable process of plate tectonics. The Pacific Ocean plate grinds against the North American plate along the San Andreas fault, which ruptures regularly in earthquakes. But the New Madrid zone sits in the middle of the quiet, rigid North American plate, about 150 miles from St. Louis.
Major bs. the New Madrid is a failed rift zone, (about the only thing plate tectonic-y around here) and much of the displacement and movement is mostly vertical, not horizontal. Attempting to compare it to San Andreas is faulty in the extreme. Better to compare it to East Africa.
Ellis' paper was the first to suggest that the plate is stretching and straining near the New Madrid zone.
Bullhocky. So what's with the last 100 years of New Madrid research, starting with Mryon Fuller, and coming up to the present? Is it as they say, pressed meat?
Yet all four groups agree that the tiny motions
they're arguing about - as much as an eighth of an inch per year - would need to be almost twice as big to build up the strain needed to unleash the huge magnitude 7 or 8 earthquakes that occurred in 1811 and at regular 500-year intervals for the past few thousand years.
I guess 1811-12 was a bad acid trip, and never *really* happened.
Either the past earthquakes weren't as big as geologists thought, the earthquake process has stopped, or it's in a quiet period that could suddenly start up again, Calais said.
Well, duh. He obviously is unaware of the fact that 100 events (most of them small) happen along the rift zone. I guess Reelfoot Lake was built by bulldozers, too.
Amid the uncertainty, policymakers are trying to decide how important the earthquake hazard is. Last week, Missouri Gov. Matt Blunt met with his cabinet officials to work on earthquake response plans. He said he was concerned that fewer than 41 percent of Missourians have earthquake insurance.
Um, our governor is very young, and his concern about equ insurance may indeed be concern for his buds in the insurance industry not being able to tap into everyone. BTW, I have eq insurance--it isn't as pricey as some believe. And our house has been eq-proofed, we keep spare food, water, fuel etc., not because we think it's gonna be big shaking anytime soon, but just in case. Those things will prove more useful short term than a piece of paper saying "I own insurance" which one can neither eat, drink, or use for a roof.
Near New Madrid is the Bootheel, which is largely rural, agricultural, and poor. They likely don't have the spare change for the insurance, the infrastructure which is insurable, or (based on historic reports) any assurances that in case of earthquake, the public drainage system would withstand such ground movement, and turn Southeast Missouri back into "Swampeast Missouri" which it was as recently as 100 years ago.
County by county, the percentage of homeowners with earthquake insurance varies wildly, and not necessarily according to how close one is to the New Madrid seismic zone. In some counties near New Madrid, fewer than 50 percent of homeowners have it.
Yet in places such as Chesterfield, which is far away from
New Madrid and would have much lower shaking, 84 percent have insurance.
People in Chesterfield live in the shadow of the Monarch levee, which failed in 1993, causing a couple billion dollars in damage to an upscale community built on gumbo flats. (The town used to be called Gumbo, in fact.) Since then, they've rebuilt, expanded, drove out nearly all the farmers, replaced them with shopping malls and corporate headquarters and in general set themselves up for another catastrophic drenching the next time the Missouri River goes major wa-ha. Because of the liquifaction effects of earthquakes on river valleys, Chesterfieldians better damn well have eq insurance, as they are much more at risk than I am. They need flood insurance too. Unfortunately stupidity insurance has not yet been invented.
If Calais lived in SE Mo., (and didn't leave upon finishing school) he likely would be the son or grandson of sharecroppers, either tied or attached to the land, a blue collar worker at some small manufactory, or a small businessman of some sort, belonging to an evangelical Christian sect, who believes that 'the Lord giveth and the Lord taketh away--blest be the name of the Lord.'
Meanwhile, insurance companies are pulling out of the Midwest, citing the great uncertainty of setting prices for unpredictable events. Last year, Safeco Insurance stopped offering earthquake policies in Tennessee. This year, they stopped in Missouri and Illinois.
Even the scientists differ on whether earthquake insurance makes sense.
Ellis, who is saying that the hazard could be as high as geologists think, did not have earthquake insurance when he lived in Memphis. He was frustrated by its high cost and high deductibles, which can now be as much as 10 or 15 percent.
"There's more chance that a tornado will destroy my house than an earthquake," he said.
But Calais, who is saying that the hazard might not be as great as previously thought, said he would nonetheless own insurance if he lived in southeastern Missouri.
"I guess I like to live on the safe side," he said.
Suggest he go to New Madrid, Caruthersville, or Hayti for a reality check.
.
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