Kinematically unrelated C–S fabrics: an example of extensional shear band cleavage from the Veporic Unit (Western Carpathians)

Year, pages: 2013, 103 - 116

Discontinuous and kinematically unrelated C–S fabrics have been recognized along the contact between the Gemeric and Veporic Units in the Western Carpathians. The formation of S and C fabrics within orthogneiss, quartzite and chloritoid-kyanite schist of the Veporic Unit is associated with Cretaceous syn-burial orogen-parallel flow and subsequent exhumational unroofing. The formation of the two fabrics characterized by distinct quartz deformation microstructure and metamorphic assemblage is separated by an inter-tectonic growth of transversal chloritoid-, kyanite-, ± monazite-bearing assemblage. The monazite U-Th-Pb concordia age of 97±4 Ma was obtained by the laser ablation ICP–MS dating method. The age of this inter-tectonic metamorphic stage together with existing ⁴⁰Ar/³⁹Ar ages on exhumation of the Veporic Unit indicate that despite the similar appearance to shear bands or C–S mylonites there is a time span of at least 10 Myr between the formation of homogeneous S fabrics and superposed discrete C fabrics in the studied rocks.

Bukovska, Z., Jerabek, P., Lexa, O., Konopasek, J., Janak, M., Kosler, J. 2013. Kinematically unrelated C–S fabrics: an example of extensional shear band cleavage from the Veporic Unit (Western Carpathians). In Geologica Carpathica, vol. 64, no.2, pp. 103-116. 1335-0552. DOI: https://doi.org/10.2478/geoca-2013-0007

Bukovska, Z., Jerabek, P., Lexa, O., Konopasek, J., Janak, M., Kosler, J. (2013). Kinematically unrelated C–S fabrics: an example of extensional shear band cleavage from the Veporic Unit (Western Carpathians). Geologica Carpathica, 64(2), 103-116. 1335-0552. DOI: https://doi.org/10.2478/geoca-2013-0007