1. Mass movements Falls, slumps flows Landslide scar/scarp
Slump/slip plane
Rupture surface (may be curved for rotational slump)
Earthflow/mudflow
Toe of landslide
Slump block

2. Classification of mass movements

4. PHYSICAL FACTORS AFFECTING AND CAUSING LANDSLIDE HAZARDS
Geological structures such as faults, joints and bedding planes are potential planes of weakness
High permeability and porosity of rock and regolith allow greater water content
Earthquakes may act as a trigger factor
Heavy rainfall saturates soils and rock increasing the weight of the deposits and increasing the effect of gravity
Snow/ice melt increases water content
Volcanic activity may melt ice and snow to give a lahar
Steeper slopes increase the effect of gravity
Previous/antecedent rainfall may leave deposits already saturated
Erosion and undercutting of the base of the slope by a river or the sea weakens the slope
Weathering breaks and loosens the rocks reducing internal cohesion. Unconsolidated, incompetent rocks fail more easily
Increased water content increases the shear stress within the sediments
Water content reduces shear resistance of sediments and acts as a lubricant between particles
Freeze thaw processes open up the pores and cracks in the sediments producing minimum density packing and allowing greater water content
The destruction of vegetation by fire/drought weakens the sediments and causes water content to increase

5. HUMAN FACTORS AFFECTING AND CAUSING LANDSLIDE HAZARDS
Overgrazing and other poor agricultural practices that reduce vegetation cover also weaken coherence of the sediment
Developments or waste tipping may add weight/load to the top of the slope
Deforestation reduces interception and transpiration increasing infiltration and overland flow
Developments may cause water or sewage leakages that increase water content
Mining and excavations may steepen slopes and cause blasting
The slope may be undercut and slopes steepened by developments such as road construction
Vibrations caused by blasting and heavy traffic can be a trigger factor
Dams and reservoirs may add weight to sediments or leakage may weaken sediments leading to slope failure