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The substance in a mudflow form when rain mixes with soil.
Formation of substance in mudflow
A mudflow or mud flow is a form of mass movement involving which involves rapid or extremely surging flow of debris that has become partially or fully liquefied by the addition of significant amounts of water to the source material.
The water added to the material can be sourced from rain water.
Thus, the substance in a mudflow form when rain mixes with soil.
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