Many West Michigan residents reported hearing loud booms on Friday -- but it wasn't an earthquake.
The booms were likely the result of a phenomenon known as ice or frost quakes -- ot a cryoseism.
A cryoseism, or frost quake, is 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 in the first cold snap of the year when temperatures drop from above freezing to below zero, particularly if there is no snow cover to insulate the ground. The primary way that they are recognized is that, in contrast to an earthquake, the effects of a cryoseism are very localized. In some cases, people in houses a few hundred yards away do not notice anything.
The reason that the vibrations do not travel very far is that cryoseisms don't release much energy compared with a true earthquake caused by dislocation of rock within the earth. On the other hand, since cryoseisms occur at the ground surface they can cause significant effects right at the site, enough to jar people awake.
Cryoseisms typically occur between midnight and dawn, during the coldest part of the night. If conditions are right, they may occur in a series of booms and shakes over a few hours or even on successive nights.
Ice quakes are generally harmless, but in rare instances the have caused damage to structural foundations or caused light shaking of the earth similar to a low-end earthquake. They are most common in the upper Midwest and northeast, locations susceptible to some of the most extreme temperature swings during the winter.
Source info: Maine Geological Survey
Copyright 2019 by WDIV ClickOnDetroit - All rights reserved.