It’s quite a surprise when the ground seems to erupt nearby.
Frigid temperatures can lead to various risks, including frostbite and even some, well, unusual noises from the ground below. You might be wondering what it means if you hear a loud bang from beneath your feet, followed by a slight tremor, almost like a mini earthquake.
Reports of alarming sounds and minor shakes came in late Monday night, covering areas from northern Tennessee to central Kentucky. Residents, still reeling from the severe winter storm affecting much of the U.S., were understandably rattled.
Such incidents could be attributed to a phenomenon called a frostquake.
What is a frost quake?
Frostquakes, or freezequakes, happen when the ground freezes rapidly, causing it to crack and emit loud sounds and vibrations. During sudden cold snaps, wet soil or shallow groundwater can freeze and expand quickly, creating pressure beneath the surface until it breaks.
These occurrences are often noted at night after a brief warm period. Water seeps into the ground during warmer hours and turns solid once it’s cold again, leading to this intense pressure buildup.
When the frozen ground finally gives way, it releases energy, resulting in those loud pops and tremors many feel.
Interestingly, a deep layer of snow can help reduce the chances of these quakes. Snow acts as an insulator, keeping the ground from cooling too rapidly. Just six inches of snow can create enough insulation to prevent the conditions that lead to frostquakes.
Are frostquakes dangerous?
Unlike typical earthquakes, frostquakes don’t involve tectonic plate movements and generally aren’t harmful.
While they can rattle windows, shake walls, and crack pavements, they’re usually just surprising little winter phenomena. Researchers noted how these frostquakes can catch homeowners off guard, making an unsuspecting winter night feel a little more intense.
Even though they might sound serious, frostquakes are much less destructive compared to regular earthquakes. They’re more like cracks formed out of pressure from cold weather.
Although the vibrations could be significant enough to make it to seismographs, the real extent of their impact isn’t entirely clear since they rarely get reported in-depth.
Where are frostquakes likely to occur?
Frostquakes mostly appear in regions that experience extreme cold and quick temperature shifts, particularly in wet soils that retain water, especially clay-rich ones.
Areas like Alaska, Canada, parts of the Midwest and Northeast U.S., as well as Iceland, frequently encounter these freezequakes due to their harsh winter conditions.
Yet, predicting them is nearly impossible, making them something you’d stumble upon rather than plan for.
A key sign that a frostquake has occurred is ground movement without any accompanying seismic activity recorded.
