Quantitative microstructures of polycrystalline quartz aggregates in a mylonite: implication for strain-rate evaluation

Eugenio Fazio (a), Rosalda Punturo (a), Rosolino Cirrincione (a), Gaetano Ortolano (a) & Antonino Pezzino (a)
(a) Department of Biological, Geological and Environmental Sciences - Earth Sciences Section - University of Catania, Corso Italia 57, 95129, Catania, Italy. E-mail: efazio@unict.it

The Montalto shear zone (MSZ) here investigated represents an excellent opportunity to study deformation processes active during Alpine Orogeny, responsible for the nowadays tectonic framework of the Aspromonte Massif that crops out in the southern part of the Calabria Peloritani Orogen. This study is devoted to the microstructural characterization of a selected suite of mylonitic leucocratic gneisses collected within the abovementioned shear zone showing a clear deformation gradient at the outcrop scale. Quantitative microstructural analysis allowed to infer via quartz paleopiezometry the possible strain rate attained during the deformational history of mylonitic rocks, in order to add helpful constraints to the tectono-thermal evolution of the shear zone.

crystallographic preferred orientation, mylonite, paleopiezometry, quartz, shear zone