Movement and transfer of rock debris in massive amount along a slope due to gravitational force is called Mass Translocation. The gravitational force is responsible for the rolling down of unorganized rock debris. Creeping down the slopes, the rock particles accumulate in the foothills. This accumulation or pile of rocks – flour is called Talus.
A cone – shaped accumulation of loose rocks is called Talus Cone.
On the basis of the amount and speed of creeping or rolling down of unorganized loose materials, mass translocation is classified into the following three groups:
1. Mass translocation with gradual flow: Due to less amount of moisture, the rocks – flour creeps slowly. The action of gradual flow occurs mostly in sub-polar cold regions. Earth Creep, Rock Creep, Talus Creep and Soil Creep are included under the action of gradual flow.
2. Mass translocation with rapid flow: Due to the adequacy of water, the rocks – flour gets saturated and creeps rapidly. Earth flow, Mud flow and Sheet flow are included under rapid flow. Mud flow can be seen creeping on the walls of the river valleys.
3. Mass translocation with extreme rapid flow: Moisture of water is not necessary for extreme rapid flow. Large rock fragments start falling suddenly by gravitational force. Landslide, Rock Slide, Rock Fall, Landslip and Debris Fall are included in extreme rapid flow.