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Shake, Rattle & Roll
01/21/09 11:12 AM
The Midwest is not an earthquake free zone . . . far from it
"I'm glad I live in the Midwest," a friend told me. "We have blizzards and tornadoes, but at least we don't have to deal with earthquakes and hurricanes."
Well, he was right about the hurricanes. But in March of 2008, those of us who inhabit the upper Great Lakes region were reminded that we do experience earthquakes, just not as often as our fellow citizens on the West Coast. Although a minor jolt (only about 5.2 on the Richter Scale), this quake was centered near Evansville, Indiana, and was felt as far away as Upper Michigan, Kansas and Georgia.
But it could have been worse and, we are told, a future trembler likely will be. The nearby New Madrid fault, which is closer to St. Louis, unleashed a series of three powerful quakes in the winter of 1811-1812. These quakes were the largest in the lower 48 states, at least in recorded history, eclipsing the "big ones" that have stricken San Francisco, LA and other West Coast cities. The 1811-1812 quakes were felt throughout the young nation and had numerous severe aftershocks, some of which continued for years. Damage to structures and persons was limited by the relative absence of European settlements in the most affected area.
Should a similar series of quakes occur today, the damage would be widespread and catastrophic. In general, building codes in the Midwest don't require structures to be resistant to earthquakes, although the US Geological Survey is trying to change that.
So, if you live in Midwest, you may not need to worry about a Katrina event, but you should still be ready to exit the building if the Earth starts moving under your feet.
Well, he was right about the hurricanes. But in March of 2008, those of us who inhabit the upper Great Lakes region were reminded that we do experience earthquakes, just not as often as our fellow citizens on the West Coast. Although a minor jolt (only about 5.2 on the Richter Scale), this quake was centered near Evansville, Indiana, and was felt as far away as Upper Michigan, Kansas and Georgia.
But it could have been worse and, we are told, a future trembler likely will be. The nearby New Madrid fault, which is closer to St. Louis, unleashed a series of three powerful quakes in the winter of 1811-1812. These quakes were the largest in the lower 48 states, at least in recorded history, eclipsing the "big ones" that have stricken San Francisco, LA and other West Coast cities. The 1811-1812 quakes were felt throughout the young nation and had numerous severe aftershocks, some of which continued for years. Damage to structures and persons was limited by the relative absence of European settlements in the most affected area.
Should a similar series of quakes occur today, the damage would be widespread and catastrophic. In general, building codes in the Midwest don't require structures to be resistant to earthquakes, although the US Geological Survey is trying to change that.
So, if you live in Midwest, you may not need to worry about a Katrina event, but you should still be ready to exit the building if the Earth starts moving under your feet.