Tectonics and culture make for interesting, and uncomfortable, bedfellows. Especially earthquakes when the happen in places not used to them like, oh, Germany, or Austria, or the Mississippi River embayment. Most of my work focuses on more gradual things, like river erosion and aggradation (building up the bed), with a few volcanic tweaks tens of thousands to hundreds of thousands of years ago. When the earth moves in my work, it is because a river carried it away. But some places are more dramatic.
The ground does not just move of its own accord. Subsurface forces, generally channeled along weak places in the crust called faults, impart a twisting, or rising and falling, or sliding motion to the seemingly solid ground. They may go for hundreds or thousands of years without anything happening on the surface, until one day, snap, shake, rattle, roll. People have just discovered a new fault, the hard way. Because many faults are not visible at the surface, or are of a kind that is not blatantly obvious to the untrained eye. Like the New Madrid fault, which in theory is smack in the middle of the earthquake-proof “stable interior craton” as John McPhee put it. Or the Humbolt Fault, running through Nebraska and Kansas.
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