1. n. [Geology]

A quality of directional uniformity in material such that physical properties do not vary in different directions. In rocks, changes in physical properties in different directions, such as the alignment of mineral grains or the seismic velocity measured parallel or perpendicular to bedding surfaces, are forms of anisotropy. (Compare with homogeneity.)

See related terms: anisotropy,  homogeneity,  isotropic,  isotropic formation,  isotropic permeability