陡坡或洞顶上的岩土体在重力作用下突然脱离母体崩落、滚动、堆积在坡脚沟谷或洞底形成结构松散、多孔隙的堆积体，经过沉积堆积，形成堆积地貌景观。

The rock-soil body on the steep slope or at the top of the cave suddenly broke away from the parent rock under gravity effect, and rolled, accumulated at the foot of the slope or the bottom of the cave to form a loose and porous accumulation body, then the accumulation landscape was formed.