sand blow

geology

Also known as: sand boil, sand volcano

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Last updated

July 20, 2026

Quick Summary

A sand blow, also known as a sand boil or sand volcano, is an area of exposed, coarse sandy soil denuded of vegetation by wind action. These formations can also occur as a result of soil liquefaction, a phenomenon where water-saturated, unconsolidated soils temporarily behave like a liquid due to seismic waves from earthquakes. When this happens, the soil's structure collapses, increasing water pressure and allowing sand to be expelled from the ground, creating sand blows. This process can lead to ground failure and damage to structures built on such soil.12

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soil liquefaction
Liquefaction may also contribute to sand blows, which are also known as sand boils or sand volcanoes. Sand blows often accompany the liquefaction of sandy or silty soil. With the collapse of the soil’s granular structure, the density of the soil increases. This increased pressure squeezes the water out of…
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Liquefaction may also contribute to sand blows, which are also known as sand boils or sand volcanoes. Sand blows often accompany the liquefaction of sandy or silty soil. With the collapse of the soil’s granular structure, the density of the soil increases. This increased pressure squeezes the water out of…
Read More