Everybody, get on the floor, let’s dance! Don’t fight the feelin’, give yourself a chance! Shake, shake, shake…
More from United States Geological Survey
Earthquakes are precisely unpredictable. But they can be anticipated with considerable accuracy.
We don’t know exactly when and where the New Madrid fault will shift. But most (though not all) argue continuing tectonic movements will eventually produce a geologic snap, crackle, and pop. The last time a major shift began (December 16, 1811) the earthquake is estimated to have been in the upper 7s or low 8s on the Richter Scale. Here’s how the naturalist and artist John James Audubon described it from 200 miles west of the epicenter.
Never had I witnessed anything like this before, though I had heard of earthquakes. I found myself rocking on my horse and I moved to and fro with him like a child in a cradle, expecting the ground to open at any moment and reveal an abyss to engulf me and all around me. The fearful convulsion lasted only minutes, however. Almost every day or night for weeks shock succeeded shock, but gradually diminished into more vibrations of the earth. The quake ceased, but not until after it had caused serious consequences in other neighboring places, rending the earth and sinking islands.
There are several million more people in the seismic zone today and a huge panoply of modern — and a fair share of pre-modern — infrastructure on which the nation’s economy depends and which was constructed without anticipating such an earthquake. This has implications for the grid, drinking water distribution, sewage systems, dams, bridges, buildings, river locks and levees, natural gas pipelines, and much more. When it happens we will be surprised and we will suffer.
But today at 10:15 many schools, hospitals, workplaces, and more in nine states are collaborating in the The Great Central US Shake Out. A reasonable investment in a bit less surprise, a bit less suffering. As KC and Sunshine Band sang, “Give yourself a chance.”
A local comment caught my eye. According to the Pantagraph (Bloomington, IL), Steve Land with the Williamson County emergency management office, “…encourages Illinoisans to have enough food, water, medicines and other necessities to last two weeks.” This will not be a 72-hour event.
February 7 was not selected at random. On this date in 1818 the “last” 7.0 plus (some say 9.0 plus) earthquake hit the region. From December 1811 until February 1818 the central United States experienced at least four earthquakes above 7.0 and as our little 2011 Virginia trembler demonstrated, the shaking travels farther this side of the Rockies.
Talk about a cascading event.
