Hercynian Metamorphism in the Catalonian Coastal Ranges
Paleozoic rocks in the Catalonian Coastal Ranges are in their largestpart affectedby alow- tovery-low gradeHercynian metamorphism. Amphibolite facies conditions are only found in restricted areas such as the southwestern part of the Guilleries massif where upper amphibolite facies conditions are rea...
| Autores: | , |
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| Tipo de recurso: | artículo |
| Fecha de publicación: | 1990 |
| País: | España |
| Institución: | Universitat Autònoma de Barcelona |
| Repositorio: | Dipòsit Digital de Documents de la UAB |
| Idioma: | inglés |
| OAI Identifier: | oai:ddd.uab.cat:182227 |
| Acceso en línea: | https://ddd.uab.cat/record/182227 |
| Access Level: | acceso abierto |
| Palabra clave: | Regional metamorphism Contact metamorphism Catalonian Coastal Ranges Hercynian Chain Metamorfismo regional Metamorfismo de contacto Cadenas costero-catalanas Cordillera Herciniana |
| Sumario: | Paleozoic rocks in the Catalonian Coastal Ranges are in their largestpart affectedby alow- tovery-low gradeHercynian metamorphism. Amphibolite facies conditions are only found in restricted areas such as the southwestern part of the Guilleries massif where upper amphibolite facies conditions are reached. Metamorphic grade increases from top to bottom of the Paleozoic stratigraphic sequence and the metamorphic peak is diachronous, being progressively older in the lower grade metamorphic zones. The isograd pattern, mineral assemblages, mineral chemistry and preserved reaction textures are consistent with a low pressure metamorphism possibly evolving from a previous Barrovian type event. The metamorphic climax in the high grade zone was reached after the seconddeformational phase. Calculatedpeak P-Tconditions are 620-640 OC and around 3.5 Kb . A latter episode of decompression from the maximum conditions to 1-2 Kb, with an associated temperature decrease to 530-550 OC, is recognized. The intrusion of late Hercynian granitoids produced contact metamorphic aureoles where the pyroxene-hornfels facies is locally reached. |
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