Granulites are fine to medium–grained
metamorphic rocks that have experienced high
temperatures of metamorphism, composed mainly of
feldspars sometimes associated with
quartz and anhydrous ferromagnesian minerals, with granoblastic texture and gneissose to massive structure. They are of particular interest to
geologists because many granulites represent samples of the deep
continental crust. Some granulites experienced decompression from deep in the
Earth to shallower crustal levels at high temperature; others cooled while remaining at depth in the Earth.
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