The process of changing the characteristics of a rock in response to changes in temperature, pressure, or volatile content. Most metamorphic changes do not include bulk chemical changes, but merely the crystallization of new mineral phases. These isochemical changes cause major textural changes. Compare metasomatism. See also barrovian-type metamorphism; barrow's zones; burial metamorphism; dynamic metamorphism; regional metamorphism; thermal metamorphism; and metamorphic grade.
Subjects: Earth Sciences and Geography.