28 December 2013

Cryoseism explained

"Around 11 p.m. Christmas Eve, people reported hearing a loud “boom” in Toronto, Newmarket, Aurora, Belleville, Richmond Hill, and Sutton. Not only was the boom heard, but it rattled houses, leaving many to believe that a tree had fallen on their rooftop...

The most likely explanation is that it was a cryoseism, also known as a frost quake.
Cyroseisms are rare, localized seismic events that occur when a sudden drop in temperature freezes the groundwater, which then expands and cracks the soil and rock. The crack will release a sudden burst of explosive energy, resulting in a loud noise and the shaking of the ground. They usually occur between midnight and dawn."
Addendum: recent occurrences here in Wisconsin:
The series of explosion-like sounds rattled residents from Waupun, Campbellsport and elsewhere Tuesday and sent Fond du Lac County sheriff's deputies out looking for a cause. Geologists say the booms were likely a phenomenon commonly known as an ice quake

3 comments:

  1. I experienced this: I live in Markham, approx. 30 km from Toronto's city centre. I was lying in bed, and my queen size bed shook and actually moved on the wood floor. And it was loud! I'd have appreciated it more if I knew what it was at the time (and stayed in bed!!)

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  2. Felt one yesterday morning as the temp plummetted in Dickinson Center, NY.

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  3. Reminds me of the Seneca Guns in my area. Of course, they are heard year round and there isn't an explanation for them.

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