What are the types of mass movements?

There are two types of mass movements. They are

• Slow movements: The movement of materials is extremely slow and imperceptible except through extended observation. Materials involved can be soil or rock debris.
• Rapid movements: Movement of water-saturated clayey or silty earth materials down low-angle terraces or hillsides is known as earthflow. When slopes are steeper, even the bedrock especially of soft sedimentary rocks like shale or deeply weathered igneous rock may slide downslope. Another type in this category is mudflow. In the absence of vegetation cover and with heavy rainfall, thick layers of weathered materials get saturated with water and either slowly or rapidly flow down along definite channels. A third type is the debris avalanche, which is more characteristic of humid regions with or without vegetation cover and occurs in narrow tracks on steep slopes. This debris avalanche can be much faster than the mudflow. Debris avalanche is similar to snow avalanche

Further Reading:

• Mass Movements
• Geography Notes