Cleavage Meaning Geology. Most slaty cleavage is also axial-plane cleavage. A pervasive parallel foliation of fine-grained platy minerals mainly chlorite and sericite in a direction perpendicular to the direction of maximum finite shortening developed in slate or other homogeneous sedimentary rocck by deformation and low-grade metamorphism.
Rock cleavage is seen in foliated rocks formed by the action of direu pressure and generally accompanied by some recrystallization and elongation with the constituent minerals in parallel arrangement. This rock formation has parallel cleavage lines. Axial-plane cleavage may be everywhere parallel to the fold hinge surface but normally cleavage fans or changes its orientation systematically with position about the fold.
Especially the difference between cleavage and fracture.
S-surface bedding or crystal orientation. Fracture is the tendency of a mineral to break along curved surfaces without a definite shape. The tendency of crystals certain minerals rocks etc to break in preferred directions so as to yield more or less smooth surfaces cleavage planes. Especially the difference between cleavage and fracture.
