Pyroclastic flow

Fast-moving current of hot gas and volcanic matter that moves away from a volcano

A pyroclastic flow, more broadly known as a pyroclastic density current, is a fast-moving current of hot gas and volcanic matter (collectively known as tephra) that flows along the ground away from a volcano. Pyroclastic currents travel at extremely high speeds and have extremely high temperatures. Pyroclastic flows are the deadliest of all volcanic hazards and are produced as a result of certain explosive eruptions.

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