A Natural Fracture is a crack that occurs naturally on the surface of a rock formation without any movement. The crack is induced as a part of reservoir stimulation and drilling operations. The Natural Fractures can be ultimately identified according to petrogenetic differences and the response characteristics of image logging and by determining the differences between natural fractures and geological features.

Reference Definition by Schlumberger Oilfield Glossary: Natural Fracture is a crack or surface of breakage within rock not related to foliation or cleavage in metamorphic rock along which there has been no movement. A fracture along which there has been displacement is a fault. When walls of a fracture have moved only normal to each other, the fracture is called a joint. Fractures can enhance permeability of rocks greatly by connecting pores together, and for that reason, fractures are induced mechanically in some reservoirs in order to boost hydrocarbon flow. Fractures may also be referred to as natural fractures to distinguish them from fractures induced as part of a reservoir stimulation or drilling operation. In some shale reservoirs, natural fractures improve production by enhancing effective permeability. In other cases, natural fractures can complicate reservoir stimulation.

Related Definitions in the Project: The Plant and Process Unit