Just about every news outlet today has a story on the "frost quake" that rocked Ohio and parts of Indiana early this morning. And why not? Spontaneous shaking of the earth caused by ice? Sounds like a recipe for an end-of-days action flick waiting to happen. They would probably cast Nicolas Cage, though, and it would probably suck, but that's beside the point.
So what exactly is a "frost quake"? It's a chance to learn a new word today: cryoseism. That's the expansion and cracking of the ground caused by freezing water. They are usually accompanied by loud noises and can be mistaken for earthquakes, as they were this morning in parts of the Midwest.
Darke County, Ohio, 911 director Brandon Redmond says reports of rumbling poured in between 5:30 a.m. and 7:30 a.m. on Thursday, though there were people saying they felt the earth moving over an eight-hour span. He says there were no reports of damage.
Emergency management officials in Ohio and Indiana and the Ohio Department of Natural Resources helped make the determination that frost quakes were at work. The Dayton Daily News reports they occur when soil soaked with moisture goes through a quick freeze, causing an expansion and contraction that can be violent.