Definition A landslide is a geological phenomenon which includes a wide range of ground movement,such as rock falls,deep failure of slopes and shallow debris flows,which can occur in offshore,coastal and onshore environments. Landslides are known also as landslips,slumps or slope failure.Definition  A landslide is a geological phenomenon which includes a wide range of ground movement, such as rock falls, deep failure of slopes and shallow debris flows, which can occur in offshore, coastal and onshore environments.  Landslides are known also as landslips, slumps or slope failure