lahar

A lahar is a dangerous combination of mud, rock, and water that flows down the side of a volcano. Some lahars are cause by volcanic eruptions.

In geology, the Javanese word lahar is used to describe a specific type of mudflow. Moving down the slopes of a volcano and often flowing into riverbeds, lahars are particularly destructive, described as "rivers of concrete." Like a muddy, rocky avalanche, they grow in size and speed as they move, picking up rocks and debris in their path. An eruption can trigger a lahar, but they're sometimes caused by extremely heavy rain.

Definitions of lahar
  1. noun
    an avalanche of volcanic water and mud down the slopes of a volcano
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    type of:
    avalanche
    a slide of large masses of snow and ice and mud down a mountain
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