title: The lateral boundary of a metamorphic core complex: The Moutsounas shear zone on Naxos, Cyclades, Greece.
abstract: We describe the structure, microstructures, texture and paleopiezometry of quartz-rich phyllites and marbles along N-trending Moutsounas shear zone at the eastern margin of the Naxos metamorphic core complex (MCC). Fabrics consistently indicate a top-to-the-NNE non-coaxial shear and formed during the main stage of updoming and exhumation between ca. 14 and 11 Ma of the Naxos MCC. The main stage of exhumation postdates the deposition of overlying Miocene sedimentary successions and predates the overlying Upper Miocene/Pliocene conglomerates. Detailed microstructural and textural analysis reveals that the movement along the Moutsounas shear zone is associated with a retrograde greenschist to subgreenschist facies overprint of the early higher-temperature rocks. Paleopiezometry on recrystallized quartz and calcite yields differential stresses of 20-77 MPa and a strain rate of 10-15-10-13s-1at 350 °C for quartz and ca. 300 °C for calcite. Chlorite geothermometry of the shear zone yields two temperature regimes, 300-360 °C, and 200-250 °C. The lower temperature group is interpreted to result from late-stage hydrothermal overprint.
authors.affiliation: Dept. Geography and Geology, University of Salzburg, Hellbrunnerstr. 34, A-5020 Salzburg, Austria.
authors.forename: Shuyun
authors.initials: S
authors.lastname: Cao
authors.affiliation: Dept. Geography and Geology, University of Salzburg, Hellbrunnerstr. 34, A-5020 Salzburg, Austria.
authors.forename: Franz
authors.initials: F
authors.lastname: Neubauer
authors.affiliation: Dept. Geography and Geology, University of Salzburg, Hellbrunnerstr. 34, A-5020 Salzburg, Austria.
authors.forename: Manfred
authors.initials: M
authors.lastname: Bernroider
authors.affiliation: State Key Laboratory of Geological Processes and Mineral Resources, China University of Geosciences, Xueyuan Rd. 29, Haidian, Beijing 100083, China.
authors.forename: Junlai
authors.initials: J
authors.lastname: Liu
keywords: Chlorite geothermometry; EBSD texture; Microstructure; Moutsounas shear zone; Naxos metamorphic core complex; Paleopiezometry