pyroclastic surge


pyroclastic surge
   A low density, dilute, turbulent pyroclastic flow, usually very hot, composed of a generally unsorted mixture of gases and comparatively low concentrations of pyroclastic particles (ash, pumice, and dense rock fragments) that travels across the ground at high speed and less constrained by topography than a pyroclastic flow; several types of pyroclastic surges can be specified (e.g., base surge, ash-cloud-surge).
   Compare: pyroclastic flow.
   SW, SN, & GG

Glossary of landform and geologic terms. 2013.

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