What is a cone-shaped deposit of sand formed during an earthquake called?

A cone-shaped deposit of sand that forms during an earthquake is referred to as a sand boil. This phenomenon occurs when the intense shaking of an earthquake causes the soil to lose its strength and behave like a liquid, a process known as liquefaction. As a result, water-saturated sand can rise to the surface, forming distinct mounds or boiles that take on a cone shape due to the upward pressure.

Sand boils are significant indicators of liquefaction, and their formation can provide insights into the subsurface conditions and the behavior of soils during seismic events. Understanding sand boils is important for geologists and engineers because they highlight areas where the ground may be susceptible to significant deformation and instability during an earthquake. The term reflects their role in very specific geological processes under seismic conditions, differentiating them from other types of sand features such as sand dunes or mounds formed by other natural processes.