![]() Very large calving events in Greenland and Antarctica have been observed to generate seismic events of magnitude 5 or larger. A large variety of seismogenic glacial processes arising from internal, ocean calving, or basal processes have been identified and studied. Occurrences Glacial cryoseisms Ī glacial cryoseism is a non-tectonic seismic event of the glacial cryosphere. The sometime superficial to moderate occurrences may range from a few centimeters to several kilometers long, with either singular or multiple linear fracturing and vertical or lateral displacement possible. Cracks and fissures may also appear as surface areas contract and split apart from the cold. Some reports have indicated the presence of "distant flashing lights" before or during a cryoseism, possibly because of electrical changes when rocks are compressed. Since cryoseisms occur at the ground surface they can cause effects right at the site, enough to jar people awake. Cryoseisms release less energy than most tectonic events. Due to lower- frequency vibrations of cryoseisms, some seismic monitoring stations may not record their occurrence. Furthermore, cryoseisms often exhibit high intensity in a very localized area, in the immediate proximity of the epicenter, as compared to the widespread effects of an earthquake. ![]() Cryoseisms can have an intensity of up to VI on the Modified Mercalli Scale. Cryoseisms can, however, be distinguished from earthquakes through meteorological and geological conditions. Initial indications may appear similar to those of an earthquake with tremors, vibrations, ground cracking and related noises, such as thundering or booming sounds. Effects Ĭryoseisms are often mistaken for minor intraplate earthquakes. Speculation has been made between global warming and the frequency of cryoseisms. The requirements for a cryoseism to occur are numerous therefore, accurate predictions are not entirely possible and may constitute a factor in structural design and engineering when constructing in an area historically known for such events. This stress builds up until relieved explosively in the form of a cryoseism. ![]() Īs water drains into the ground, it may eventually freeze and expand under colder temperatures, putting stress on its surroundings. For the 2010 novel, see Ice Quake (novel).Ī cryoseism, ice quake or frost quake, is a seismic event caused by a sudden cracking action in frozen soil or rock saturated with water or ice, or by stresses generated at frozen lakes. In the Canadian province of British Columbia, in a village called Lytton, the country's all-time hottest temperature record was broken three times, with the highest recorded on Tuesday at 121.28F."ice quake" redirects here. Whatever the cause of the Alaska ice quakes, the fact remains that northwestern parts of North America are experiencing unusually hot temperatures at the moment. Likewise, this land can rise again when the glaciers melt.Ĭhris Rollins, the lead author, found a subtle correlation between this earth rebound effect and earthquakes. In a summary of the paper, the University of Alaska Fairbanks, with which the study's lead author is affiliated, said the weight of glaciers can cause the land beneath them to sink. In a March 2021 research article, scientists found that ice loss near Alaska's Glacier Bay National Park has influenced the timing and location of earthquakes in the area. The Encyclopedia Brittanica, however, uses that same definition for both ice quakes and frost quakes.īoth are examples of a cryoseism-in which snow, ice, or rock suddenly cracks because of changes in stress, whether it be expansion or contraction.įurther complicating matters is the fact that scientists have known for years that melting glaciers have caused earthquakes in areas that are otherwise stable. It states that a frost quake occurs when very wet soil freezes quickly and expands, which then puts stress on the soil and causes it to fracture. Ice quakes may also be referred to as frost quakes, though the AGS makes a distinction between the two. Ice quakes are not the same as earthquakes, which are instead caused by the shifting movements of tectonic plates. This causes cracks and ridges to form in the ice, which can produce seismic waves that may then be recorded by seismographs. Police Investigating Over 65 Deaths Since Triple Digit TemperaturesĪt that strength, neither quake was likely to have been strongly felt, if at all.Īn ice quake is a geological event in which ice expands during sudden warm periods and is unable to accommodate the change in volume, according to the Alberta Geological Survey (AGS).Vancouver Records More Than 130 Deaths in Three Days Due To West Coast Heat.Hundreds Hospitalized as Historic Temperatures Roll Over Pacific Northwest.
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