A form of mass movement, where water-saturated, weak-slope material flows under the action of gravity at speeds between 10 cm s−1 to 10 cm day−1. A rapid earth flow generally quickly follows the initial fall-slide phase (Di Crescenzo and Santo (1999) Geogr. Fis. Din. Quat. 22). Di Crescenzo and Santo (2005) Geomorph. 66, 1–4 find relationships between: the height of the landslide crown zone and the slope relief energy; the slope relief energy and the sliding zone area; and the landslide area and the basin area.