Sprickfält

Sprickfält is a geologic term referring to a field or network of fractures—joints and faults—in rock. It describes the pattern and distribution of cracks that accommodate deformation of a rock mass. Sprickfält can form under various processes, including tectonic stresses that create joints by brittle failure, cooling and contraction of rock, or chemical weathering that weakens rock along planes of weakness. The resulting crack patterns may be open or filled with minerals and can range from sparse, widely spaced joints to dense networks with multiple fracture orientations.

Common characteristics of sprickfält include the orientation sets (principal strikes) of fractures, fracture density, and spacing, all of which depend on rock type, stress history, and moisture conditions. In structural geology, sprickfält are analyzed to infer the ambient stress field, fracture mechanics, and the deformation history of a rock mass. In hydrogeology, fracture networks govern fluid flow and storage, often dominating permeability in otherwise low-permeability rocks. In engineering and mining, mapped sprickfält inform stability assessments, excavation planning, and the risk of water ingress or rock bursts.

Measurement and mapping of sprickfält typically involve field surveys of outcrops, recording strike and dip of fractures, calculating fracture density, and constructing 3D models from borehole data or remote sensing data. Terminology varies; sprickfält may also be referred to as fracture fields, joint networks, or fracture systems in English-language geology.