Geochronology of fluid-induced eclogite and amphibolite facies metamorphic reactions in a subduction–collision system, Bergen Arcs, Norway
نویسندگان
چکیده
منابع مشابه
Diffusion versus recrystallization processes in Rb–Sr geochronology: Isotopic relics in eclogite facies rocks, Western Gneiss Region, Norway
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 (...
متن کاملEclogite-facies fluid infiltration: constraints from dO zoning in garnet
In situ analysis reveals that eclogite-facies garnets are zoned in dO with lower values in the core and rims that are *1.5 to 2.5 % higher. This pattern is present in 9 out of 12 garnets analyzed by SIMS from four orogenic eclogite terranes, and correlates with an increase in the mole fraction of pyrope and Mg/Fe ratio from core to rim, indicating prograde garnet growth. At the maximum temperat...
متن کاملPrograde amphibolite facies to ultrahigh-pressure transition along Nordfjord, western Norway: Implications for exhumation tectonics
[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...
متن کاملAn albite-anorthite assemblage in low-grade amphibolite facies rocks
Poikiloblastic amphibole schists from an ophiolite series in the vicinity of the Tertiary Bergell granite contain the assemblage albite (An 0)-anorthite (An 95), actinolite-pargasite, together with clinozoisite. TEM illustrates how large andesine crystals with a periodic APB (anti-phase boundaries) structure of e plagioclase change over a few hundred angstroms to pure albite and pure PT anorthi...
متن کاملLate Miocene–Pliocene eclogite facies metamorphism, D’Entrecasteaux Islands, SE Papua New Guinea
The D’Entrecasteaux Islands of south-eastern Papua New Guinea are active metamorphic core complexes that formed within a region where the plate tectonic regime has transitioned from subduction to rifting. While rapid, post 4 Myr exhumation and cooling of amphibolite and greenschist facies rocks that constitute the footwall of the crustal scale detachment fault system have been previously docume...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
ژورنال
عنوان ژورنال: Contributions to Mineralogy and Petrology
سال: 2007
ISSN: 0010-7999,1432-0967
DOI: 10.1007/s00410-007-0272-y