epidote-amphibolite facies


epidote-amphibolite facies

One of the major divisions of the mineral facies classification of metamorphic rocks, encompassing rocks that formed under moderate temperature (500–750°F, or 250–400°C) and pressure conditions. This facies grades into the greenschist facies under less intense metamorphic conditions and into the amphibolite facies with greater temperature and pressure. Typical minerals include biotite, almandine garnet, plagioclase, epidote, and amphibole. Chlorite, muscovite, staurolite, and chloritoid may also occur.

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