A series of frost quakes in Toronto overnight startled residents, as the frigid temperatures combined with the new ice sparked the quakes.
As temperatures quickly fall, water freezes, and the new ice expands, stressing the soil and bedrock.
The stress builds until the rock or soil cracks, with a loud boom and sometimes accompanying shaking happening.
The phenomenon is also known as a cryoseism. The Main Department of Agriculture, Conservation, and Forestry describes it as “a natural phenomenon that produces ground shaking and noises similar to an earthquake, but is caused by sudden deep freezing of the ground.”
They typically occur between midnight or dawn.
Mike Leibovitz, who lives in Thornhill, said that at least four frost quakes hit near his house early in the morning, around 2:30 a.m.
“To be honest, we literally thought that our roof broke or something. Our house pretty much shook,” he told the National Post.
“It was pretty loud. I mean, the two of us woke up out of deep sleep, it woke my daughter up. It definitely was a boom and my house, my roof was shaking.”
Paige Kruger, who lives at Lawrence and Avenue, also heard loud booms from the quakes.
“My dad was like walking around the house to see if anyone broke in,” she said.
“Then it sounded like somebody was basically banging around in the walls of our house.”