Land and Mud Slide: Overview

A landslide is a geological phenomenon characterized by massive ground movement such as rock falls and deep slope failures, also called mass wasting. A mudslide, also called debris flow, lahar, mudflow, or debris avalanche, is a landslide of mud and is the most rapid type of mass wasting that often flows in channels of "slurry".

Some landslides move slowly, whereas others strike almost instantaneously. Landslides are caused by disturbances in the natural stability of state and generally gravity acting over a steepened slope is the major cause of landslides and mudslides. There are other factors that catalyze the process such as erosion by rivers, heavy rains, earthquakes, volcanic eruptions, and groundwater pressure.

Landslides and mudslides are usually associated with heavy periods of rainfall and areas where vegetation has been destroyed by wildfires or human activity are particularly vulnerable. Other areas more susceptible to landslides and mudslides include areas where past instances have occurred before: steep slopes, channels along a stream or river, and areas where surface runoff is directed.