Table 1.

Surface landforms commonly associated with mass movement activity (adapted from Soeters & Van Western 1996).

Terrain landformsRelation to slope instabilityImage characteristics
Hummocky or irregular slope morphology.Relief associated with shallow slope movements or small retrogressive slides blocks.Coarse image texture contrasts with surrounding smooth areas
Step-like slope morphology.Retrogressive landsliding or successive landslide features.Step-like slope appearance with regular tonal changes
Arcuate backscarp and crown wall.Head part of landslide with exposure of failure plane.Curved lighter toned scarp.
Back-tilted slope facets.Rotational movement of landslide blocks.Tonal changes associated with oval or elongate depressions.
Differential vegetation associated with changing drainage conditions.Stagnated drainage in back-tilted block, seepage at frontal lobes, differential conditions and ponding within landslide body.Darker toned areas associated with wetter ground conditions. Water ponding and isolated pockets of hydrophilic vegetation.
Sharp break of slope at main landslide scarp.Landslide scarp generated through rotational or translational movement.Sharp tonal change at break of slope.
Pressure ridges and transverse ridges.Landslide toe and overriding of surface by landslide material.Coarse image texture overlying smoother image areas.
Lateral ridges or scarps.Shallow translational landsliding.Sharp tonal changes at the edge of landslide area.