‘Icequakes’ possible across Midwest amid arctic temperatures

Locals across the Midwest, particularly in Greater Chicago, may hear a sudden “boom” over the weekend – the result of what meteorologists call a frost quake, a weather phenomenon that takes place when temperatures plummet and groundwater freezes quickly.

More than 210 million people in the United States are under cold weather advisories, as a major winter storm is forecast to spread heavy snow, sleet and dangerous ice across at least two dozen states starting on Friday, and continuing into the weekend.

Frost quakes, also called icequakes, are seismic events caused by a sudden cracking action in frozen soil or rock saturated with water or ice.

The rapid bursting sounds like a noisy quake, along with possible shaking, and can lead some people to think their homes are being broken into or gunshots are being fired.

Frost quakes are too small to be picked up by a seismograph, so they are difficult to prove, geologist Jeri Jones of Jones Geological Services said last year. Jones said they only can be heard about 300 feet away.

“Since water expands when it freezes, it can basically push apart dirt and rocks. If this expansion happens all at once, say a rock under pressure gives way and breaks, it can lead to the sound and earthquake like sensation,” AccuWeather senior meteorologist Adam Douty wrote in an AccuWeather report.

Frost quakes, also known by the dull geological term “cryoseisms” are often mistaken for earthquakes, according to AccuWeather, since initial indicators may appear similar, but meteorologists said they have nothing to do with tectonic plates.

Where do

icequakes occur?

The phenomenon takes place frequently across the northeastern United States, as well as Alaska, according to AccuWeather.

They also take place in Canada and Iceland.

When imagining how they work, Dave Call, a meteorologist at Ball State University, said to think of a bottle of liquid in a freezer, expanding and exploding.

“It’s more of a noise phenomenon, like a balloon popping, than a physical danger,” Call previously told USA Today.

He compared frost quakes to the familiar phenomenon of potholes: Water seeps into cracks in the pavement, freezes and expands.