Landslide Types

Landslides or slope movements can be classified in many ways. There are many attributes used as criteria for identification and classification including:

• Rate of movement: This ranges from very slow creep (millimetres/year) to extremely rapid (metres/second).
• Type of material: Landslides are composed of bedrock, unconsolidated sediment and/or organic debris.
• Nature of movement: The moving debris can slide, slump, flow or fall.

Common landslide types are:

Slump: complex movement of materials on a slope; includes rotational slump. NOTE: This is the same type of landslide that is occuring in Anaheim Hills.

Slide: movement parallel to planes of weakness and occasionally parallel to slope.

Creep: gradual movement of slope materials

Topple: the end-over-end motion of rock down a slope.

Fall: material free falls.

Flow: viscous to fluid-like motion of debris.

Torrent::a sporadic and sudden channelized discharge of water and debris.