regional metamorphism

American  

[ree-juh-nuhl met-uh-mawr-fiz-uhm] / ˈri dʒə nəl ˌmɛt əˈmɔr fɪz əm /

noun

1. Geology. metamorphism that affects rocks in a widespread region under conditions of high pressure and temperature, often resulting in the formation of such banded and crystalline rocks as gneiss and schist.

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regional metamorphism Scientific  

/ rē′jə-nəl /

1. A type of metamorphism in which the mineralogy and texture of rocks are changed over a wide area by deep burial and heating associated with the large-scale forces of plate tectonics. In regional metamorphism, rocks that form closer to the margin of the tectonic plates, where the heat and pressure are greatest, often differ in their minerals and texture from those that form farther away.

2. Compare contact metamorphism

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Example Sentences

Greenschist rocks form under relatively low pressure and temperatures and represent the fringes of regional metamorphism.

From Textbooks • Jan. 1, 2017

Most regional metamorphism takes place within continental crust.

From Textbooks • Jan. 1, 2015

The quartz crystals show no alignment, but the micas are all aligned, indicating that there was directional pressure during regional metamorphism of this rock.

From Textbooks • Jan. 1, 2015

Oceanic crustal rock can be metamorphosed near the spreading ridge where it was formed, but most other regional metamorphism takes place in areas where mountain ranges have formed, which are most common at convergent boundaries.

From Textbooks • Jan. 1, 2015

This regional metamorphism, as it is termed, has affected the rocks in certain instances throughout districts measuring many hundreds of square miles in surface extent, and with a vertical range of many thousands of feet.

From North America by Russell, Israel C. (Cook)