granulite
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Granulite is a granular metamorphic rock primarily composed of feldspar and quartz. It is classified within the granulite facies, which represents the highest temperature and pressure conditions typically found in regional metamorphism. These conditions can range from 650–1,100 °C (1,200–2,000 °F) and pressures of 3 to 10 kilobars.12
Characteristic minerals in granulite facies rocks include pyroxene, biotite, garnet, calcium plagioclase, and quartz or olivine. A key feature of granulite is its low water content, as water is expelled by the intense heat and pressure. These rocks often have a texture similar to plutonic igneous rocks, with only weak schistosity. Granulite facies rocks are predominantly found in ancient Precambrian continental areas.23
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PrecambrianDistinctive featuresThe second occurs in granulite-gneiss belts that were recrystallized in the Archean mid-lower crust under metamorphic conditions associated with high-temperature granulite and amphibolite facies. Thus, granulites, which typically contain the high-temperature mineral hypersthene (a type of pyroxene), are a characteristic feature of many Precambrian orogenic belts that have been…
Read MoreThe second occurs in granulite-gneiss belts that were recrystallized in the Archean mid-lower crust under metamorphic conditions associated with high-temperature granulite and amphibolite facies. Thus, granulites, which typically contain the high-temperature mineral hypersthene (a type of pyroxene), are a characteristic feature of many Precambrian orogenic belts that have been…
Read More- PrecambrianGranulite-gneiss rock types
…higher temperature associated with the granulite facies, the rocks contain pyroxene and hypersthene and so can be called granulites.
Read More…higher temperature associated with the granulite facies, the rocks contain pyroxene and hypersthene and so can be called granulites.
Read More - PrecambrianGranulites and gneisses
These highly deformed and metamorphosed rocks are similar to those of the Archean Eon and occur in many Proterozoic orogenic belts such as the Grenville in Canada, the Pan-African Mozambique belt in eastern Africa and Madagascar, the Musgrave and Arunta
Read MoreThese highly deformed and metamorphosed rocks are similar to those of the Archean Eon and occur in many Proterozoic orogenic belts such as the Grenville in Canada, the Pan-African Mozambique belt in eastern Africa and Madagascar, the Musgrave and Arunta
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