The frost weathering (called also frost wedging) The frost weathering (including frost wedging) is caused by the volume expansion of freezing water, contained in pores and crevices. It is one of the most important processes of physical weathering. Comparatively small forces are sufficient to separate blocks limited by fissures and bedding planes from the massive bedrock. Meanwhile much more force is needed to produce new crevices in the solid bedrock. The process of removal of blocks from the massive rock is called block decay.
In the high mountains, stone fragments separated by frost weathering fall down on the bottom of the rock faces. Where this process occurs frequently, the fragments accumulate piles of debris at the bottom of the rock faces.