Sand Boil Forms: Example from 1989 Loma Prieta earthquake

24s Novice

What is a sand volcano??

Sand Boil: sand-laden water can be ejected from a buried liquefied layer and erupt at the surface to form sand volcanoes; the surrounding ground often fractures and settles. Definition & photo from USGS.

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Highly generalized animation reflects the arrivals of P, S, and surface waves to 3 closely spaced buildings. Exaggerated movement of the buildings reflects the relative motion recorded by the seismograms.

Animation Novice

Liquefaction is a process by which water-saturated sediment temporarily loses strength and acts as a fluid. This effect can be caused by earthquake shaking.

Animation Novice

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