This headline caught my eye, as I grew up in the Chicago area. I’ll eagerly await reports from my family as to the horrific shocks they no doubt felt in the suburbs…
According to CNN,
The earthquake occurred in the Wabash Valley fault system, adjacent to the New Madrid Seismic Zone, Applegate said.
That zone, named for the town of New Madrid, Missouri, was the site of a series of huge tremors in 1811 and 1812.
We haven’t heard much about the New Madrid fault for a while, though a massive midwest earthquake is likely, in fact inevitable. In 1811-1812 the region was subject to a devastating series of tremors with magnitudes between 7.0 and 7.9. One of the big concerns for a modern earthquake of this magnitude is its potential nonlocality: In California, the ground is, roughly speaking, composed of lots of soft sediments, which tend to dampen the effects of a quake and keep it from spreading over a large region. The ground in the midwest is much more rigid and can transmit strong shocks over a much greater distance. For instance, according to Wikipedia, “The [1811-1812] earthquakes were felt as far away as New York City and Boston, Massachusetts, where churchbells rang.”
A few years ago, there was a bit of a New Madrid fault hysteria. A ‘scientist’ named Iben Browning, who claimed to have predicted the 1989 San Francisco earthquake using an understanding of tidal effects, predicted a New Madrid earthquake for December 3, 1990. Despite the fact that serious earthquake experts dismissed Browning’s predictions as ludicrous, the media managed to whip up a huge amount of ‘earthquake hysteria’ amongst the population. I remember that my Dad’s company, among many in downtown Chicago, had risk assessment studies done about the potential effects of the coming earthquake. Quoting from the article linked to above,
The public, meanwhile, its fears stoked by media hype, made its own plans for Earthquake Day. Many schools in four states closed. Schools that stayed open told students to bring three-day emergency rations with them or else stay home. Once-a-year charity benefits scheduled for December 2 and 3 were cancelled for fear no one would show up. Businesses closed. Supermarkets sold out of bottled water, candles, and flashlight batteries. Children had nightmares. Parents had nightmares. Everyone had nightmares.
Nothing happened, of course, but the threat of a damaging earthquake emanating from the New Madrid fault is very real. Hopefully people will listen to the legitimate scientific experts instead of quirky pseudo-scientists to understand the risks and consequences.