Hercynian Metamorphism in the Catalonian Coastal Ranges

Paleozoic rocks in the Catalonian Coastal Ranges are in their largestpart affectedby alow-tovery-low grade Hercynian 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...

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Bibliographic Details
Authors: Sebastián Castellanos, Alfredo, Reche Estrada, Joan, Durán Gilabert, Hortensia
Format: article
Status:Published version
Publication Date:1990
Country:España
Institution:Universidad de Barcelona
Repository:Dipòsit Digital de la UB
OAI Identifier:oai:diposit.ub.edu:2445/32687
Online Access:https://hdl.handle.net/2445/32687
Access Level:Open access
Keyword:Metamorfisme
Paleozoic
Serralada Litoral Catalana
Metamorphism (Geology)
Catalan Coastal Range (Catalonia)
Description
Summary:Paleozoic rocks in the Catalonian Coastal Ranges are in their largestpart affectedby alow-tovery-low grade Hercynian 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.