A “frost quake” which occurred in the South Frontenac area Monday Jan 07, at 2:36 pm has been verified by Dr Alex Braun, of Queen’s Department of Geological Sciences at Queen’s.
In the Perth Road area, it sounded like a loud explosion followed by rumbling. In Sydenham, it was a sudden deep bang that seemed to come from several hundred yards away.
Queen’s has one of only 30 superconducting gravimeters in the world: an extremely sensitive instrument able to detect frost quakes. The phenomenon, technically called a cryosiesm, is triggered by rapid shifts in winter temperatures. When water drains into the soil during a rainy warm spell, then freezes and expands rapidly, pressure from the sudden expansion can result in a sudden cracking in the surface soil. Much smaller than earthquakes, and localized close to the surface, frost quakes are not usually felt over an area larger than a few metres.
However, because of its winter temperature swings, frost quakes are relatively common in the Great Lakes-St Lawrence area. Monday’s is considered to have been larger than most.