metamorphism

[ met-uh-mawr-fiz-uhm ]

noun

1. Geology. a change in the structure or constitution of a rock due to natural agencies, as pressure and heat, especially when the rock becomes harder and more completely crystalline.
2. Archaic. metamorphosis.

metamorphism

/ ˌmɛtəˈmɔːfɪzəm /

noun

1. the process by which metamorphic rocks are formed
2. a variant of metamorphosis

metamorphism

/ mĕt′ə-môr′fĭz′əm /

1. The process by which rocks are changed in composition, texture, or structure by extreme heat and pressure.
2. ◆ In prograde metamorphism metamorphic rocks that were formed under low pressure and temperature conditions undergo a second metamorphic event in which they are exposed to higher pressures and temperatures.
3. ◆ In retrograde metamorphism metamorphic rocks that were formed under high pressure and temperature conditions undergo a second metamorphic event in which they are exposed to lower pressures and temperatures.
4. See more at contact metamorphism

Word History and Origins

Origin of metamorphism¹

First recorded in 1835–45; meta- + -morphism

Example Sentences

As global stocks of these rocks build up they can then release their carbon during tectonic processes, including mountain building and metamorphism.

From Science Daily

Because seifertite and stishovite are easily disturbed by thermal metamorphism, they inferred the silica fragment likely originated from the collision that formed the Aristarchus crater.

From Science Daily

On Earth, metamorphism usually happens slowly and deep underground.

From National Geographic

In the Australian rocks with ancient stromatolites2, laminations are clearly visible; in the Greenland samples, however, the proposed laminations are less clear, and the degree of metamorphism is higher than that of the Australian rocks.

From Nature

Menzies, O. N., Bland, P. A., Berry, F. J. & Cressey, G. A Mössbauer spectroscopy and X-ray diffraction study of ordinary chondrites: quantification of modal mineralogy and implications for redox conditions during metamorphism.

From Nature