Ну, не знаю, здесь (https://pubs.usgs.gov/fs/2004/3072/fs-2004-3072.html) так пишут:
The term “landslide” describes a wide variety of processes that result in the downward and outward movement of slope-forming materials including rock, soil, artificial fill, or a combination of these. The materials may move by falling, toppling, sliding, spreading, or flowing.
no subject
The term “landslide” describes a wide variety of processes that result in the downward and outward movement of slope-forming materials including rock, soil, artificial fill, or a combination of these. The materials may move
by falling, toppling, sliding, spreading, or flowing.