A fracture is an interior cleavage or a break within a metamorphic rock. It does not result from movement. A fracture at a location where the displacement of rock is involved is called a "fault." A "joint" is a fracture in which the walls of a fracture have moved only in relation to each other.
Fractures are also found in sedimentary rocks including carbonates. Carbonates, such as limestone, fracture in a distinctive rhombohedral pattern while others, such as coal – a form of carbon – fracture along a single plane. Diamonds, being carbon subjected to high geologic pressures over extended periods of time, likewise fracture along a single plane.
Trenchlesspedia Explains Fracture
Fractures mean that the ability of the rocks to be penetrated by water is enhanced greatly because the pores of the metamorphic rock become connected to each other. This means that fractured metamorphic rock, such as limestone, may allow groundwater to infiltrate the bores created by the use of trenchless technology and, over time, may compromise the pipes or conduits located within those bores. This means that the bore's design path used in the trenchless project must be carefully evaluated for the presence of calcites, such as limestone and dolomite.