Interactions between plutonism and detachments during metamorphic core complex formation, Serifos Island (Cyclades, Greece)

Author(s)
Aurélien Rabillard, Laurent Arbaret, Laurent Jolivet, Nicole Le Breton, Charles Gumiaux, Romain Augier, Bernhard Grasemann
Abstract

In order to better understand the interactions between plutonic activity and strain localization during metamorphic core complex formation, the Miocene granodioritic pluton of Serifos (Cyclades, Greece) is studied. This pluton (11.6-9.5 Ma) intruded the Cycladic Blueschists during thinning of the Aegean domain along a system of low-angle normal faults belonging to the south dipping West Cycladic Detachment System (WCDS). Based on structural fieldwork, together with microstructural observations and anisotropy of magnetic susceptibility, we recognize a continuum of deformation from magmatic to brittle conditions within the magmatic body. This succession of deformation events is kinematically compatible with the development of the WCDS. The architecture of the pluton shows a marked asymmetry resulting from its interaction with the detachments. We propose a tectonic scenario for the emplacement of Serifos pluton and its subsequent cooling during the Aegean extension: (1) A first stage corresponds to the metamorphic core complex initiation and associated southwestward shearing along the Meghàlo Livadhi detachment. (2) In the second stage, the Serifos pluton has intruded the dome at shallow crustal level, piercing through the ductile/brittle Meghàlo Livadhi detachment. Southwest directed extensional deformation was contemporaneously transferred upward in the crust along the more localized Kàvos Kiklopas detachment. (3) The third stage was marked by synmagmatic extensional deformation and strain localization at the contact between the pluton and the host rocks resulting in nucleation of narrow shear zones, which (4) continued to develop after the pluton solidification.

Organisation(s)
Department of Geology
External organisation(s)
Université d’Orléans, Centre National De La Recherche Scientifique (CNRS)
Journal
Tectonics
Volume
34
Pages
1080-1106
No. of pages
27
ISSN
0278-7407
DOI
https://doi.org/10.1002/2014TC003650
Publication date
2015
Peer reviewed
Yes
Austrian Fields of Science 2012
105106 Geodynamics
Keywords
ASJC Scopus subject areas
Geochemistry and Petrology, Geophysics
Portal url
https://ucrisportal.univie.ac.at/en/publications/interactions-between-plutonism-and-detachments-during-metamorphic-core-complex-formation-serifos-island-cyclades-greece(cca88d05-2774-4311-a5c9-64f1b7f07cb4).html