3. How are mass movement events triggered? 4. What observations might suggest that the area is unstable and may start to move? 5. How can we mitigate against mass movement hazards? We start with a discussion of the forces acting at the surface that cause mass movements. Gravity Gravity is the main force responsible for mass movements.
Structural and geological factors, as already described, can determine the development of the movement, inducing the presence of mass in kinematic freedom. Types and classification. In the following table shows a schematic landslide classification adopting the classification of Varnes 1978 and taking into account the modifications made by Cruden and Varnes, in 1996. Some integration has been made by using the definitions of Hutchinson (1988) and Hungr et al. 2001.
Mass movements can be divided into four main classes. These are falls, slides, creeps and flows. The classes are based on how quickly the rock and sediment moves and how much water there is. Steep and unstable slopes are more likely to have a mass movement than gentle and stable slopes.
Mass movement or mass wasting is a natural phenomenon initiated by the force that attracts any object with mass. In recent years, the definition of mass movement has been enlarged to include mass wasting processes or natural erosion and the slow submerging of the Earth’s ground surface.
A slump is a type of mass wasting that results in the sliding of coherent rock material along a curved surface. A slump is sometimes referred to as a rotational slide because a portion or block of the slope 'slides' down as it 'rotates' around an axis parallel to the slope.