case hardening
Nota de aplicación
Describes a process of weathering in which the outer shell of rock becomes more resistant to erosion than its interior. Case hardening occurs by strengthening the exterior shell of the rock or by weakening of the rock's interior. In materials such as sandstone a greater accumulation of cements holding individual grains together at the surface causes shell strengthening. Case hardening in crystalline rock takes place when bonds are broken in the i…