migmatite

migmatite
Rock composed of a metamorphic host material that is streaked or veined with granite; the name means "mixed rock.

" Many migmatites probably represent partial fusion of the metamorphic host; some components of the rock are fused and gather to produce the streaks of granite. Migmatite also can form near large intrusions of granite when some of the magma is injected into neighbouring metamorphic rocks.

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rock
      in geology, rock composed of a metamorphic (altered) host material that is streaked or veined with granite rock; the name means “mixed rock.” Such rocks are usually gneissic (banded) and felsic rather than mafic in composition; they may occur on a regional scale in areas of high-grade metamorphism.

      Many migmatites probably represent the partial fusion of the metamorphic host during extreme metamorphism; the components of the rock with the lower melting temperatures are fused and gather to produce the streaks of granite. The migmatites of some Precambrian metamorphic terrains may be the result of this process. Migmatite also can form near large intrusions of granite when some of the magma is injected into the neighbouring metamorphic rocks.

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Universalium. 2010.

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  • migmatite — noun any rock of mixed appearance, being an intimate mixture of granite and older rock, specifically from intense metamorphism which partially melts the rock, causing it to recrystallize in a state intermediate between igneous and metamorphic …   Wiktionary

  • Migmatite — Migmatịte   [zu griechisch mĩgma »Mischung«], Singular Migmatịt der, s, Mischgesteine, in ihrer chemischen Zusammensetzung und ihrem Gefüge zwischen metamorphen Gesteinen und Magmatiten stehende Gesteine mit einem unveränderten, hochmetamorphen …   Universal-Lexikon

  • migmatite — mig·ma·tì·te s.f. TS petr. roccia cristallina mista, prodotto di solidificazione del migma {{line}} {{/line}} DATA: 1957. ETIMO: der. di migma con 2 ite …   Dizionario italiano

  • migmatite — pl.f. migmatiti …   Dizionario dei sinonimi e contrari

  • migmatite — [ mɪgmətʌɪt] noun Geology a rock composed of two intermingled but distinguishable components, typically a granitic rock within a metamorphic host rock. Origin early 20th cent.: from Gk migma, migmat mixture + ite1 …   English new terms dictionary

  • migmatite — mig·ma·tite …   English syllables

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