Processes

Metamorphism

Citation Formats

General Reference

Earth and Environment Atlas. "Metamorphism." Accessed August 30, 2026. https://dev-earth.interactiveatlas.org/processes/metamorphism.

APA Style

Earth and Environment Atlas. (n.d.). Metamorphism. Retrieved August 30, 2026, from https://dev-earth.interactiveatlas.org/processes/metamorphism

BibTeX

@misc{earthandenvironmentatlas-metamorphism,
  author = {Earth and Environment Atlas},
  title = {Metamorphism},
  year = {2026},
  url = {https://dev-earth.interactiveatlas.org/processes/metamorphism},
  note = {Accessed August 30, 2026}
}

The transformation of existing rock, the protolith, into rock with a different mineral composition or texture, usually above 150 degrees Celsius and often at elevated pressure or in the presence of chemically active fluids, while the rock stays mostly solid. Regional, contact, hydrothermal, shock and dynamic metamorphism differ in their characteristic temperatures, pressures and fluids, and the process is distinct from weathering and diagenesis, which work at or just beneath the surface.

Facts

Timescale

Thousands of years near a hot intrusion (contact metamorphism) to tens of millions of years during regional metamorphism accompanying mountain building. 1

Driving Force

Elevated heat and pressure, generated by burial, tectonic stress or contact with magma, acting on existing rock without melting it. 1

Resulting Feature

Recrystallizes the minerals and often the texture of the parent rock, producing metamorphic rock such as marble from limestone or schist from shale. 1

Significance

Metamorphic rock and its mineral assemblages record the temperature and pressure history of a rock, revealing its tectonic setting long after the original rock is gone. 1

Cross-Tradition Connections