Structural development and petrofabrics of eclogite facies shear zones, Bergen Arcs, western Norway: implications for deep crustal deformational processes
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چکیده
منابع مشابه
Eclogitization of lower crustal granulites by fluid migration through shear zones
The granulite facies assemblages of the anorthositic rocks of the Bergen Arcs (stable at 800 -900°C and 10 kbar) have been transformed to eclogite facies assemblages (stable at 700 -750°C and 16-19 kbar) in the vicinity of Caledonian shear zones. This section of the root zone of the Caledonian mountain chain reveals a deep polymetamorphic crust where Precambrian granulites (mean density 3.02 g ...
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Rb–Sr and U–Pb isotopic data for granulite facies rocks, forming textural relics with respect to eclogite facies metamorphism in the Western Gneiss Region (WGR) of Norway, highlight the importance of textures and mineral reaction kinetics for the interpretation of geochronological data. Studied rocks from Bårdsholmen, southern WGR, were subjected to granulite facies metamorphism at 955 ± 3 Ma (...
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[1] The Nordfjord area of western Norway hosts one of the best known provinces of ultrahigh-pressure (UHP) rocks in the world, yet the nature of the transition from the UHP rocks into surrounding amphibolite-facies crust has remained unclear. New thermobarometry of phengiteand kyanite-bearing eclogites shows that this transition is unbroken by major structures: the pressure and temperature grad...
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ژورنال
عنوان ژورنال: Journal of Metamorphic Geology
سال: 1992
ISSN: 0263-4929,1525-1314
DOI: 10.1111/j.1525-1314.1992.tb00075.x