A fracture can sometimes form a deep, wide crack in the rock.

A fracture will sometimes form a deep fissure or crevice in the rock.

As it split, steep fractures formed and filled with molten rock from below.

Some hydraulic fractures form naturally: certain dykes are examples.

These fractures often form rock columns that are typically hexagonal, but also four to eight sided.

During the cooling of a thick lava flow, contractional joints or fractures form.

The expansion sets up stresses which cause fractures parallel to the rock surface to form.

During a collision when the strain reaches the breaking point of the rock a fracture will form in the rock.

This causes white fractures to form on the surface and give white cast iron the name.

These fractures form high, narrow, straight passages that persist in widespread closed loops.