Deformazione duttile nei neks di granati budinati in facies granulitica. Ductile deformation within necks of garnet boudins formed at granulite facies conditions.

In this work we have studied a sample that comes from a shear zone in Amaroni, in the Calabrian Serre Massif. In this place there is an outcropping portion of hercynian continental crust with, its deepest part, exhumed by tertiary tectonic. The sample comes from migmatitic paragneiss; the ages obtained by Zircons dating, point the registered metamorphic peak to an age of about 300 My (Schenk 1984; Micheletti et al., 2008). The metamorphic peak is related to high magmatic activity, with a high emplacement of granitoids magmas in the intermediate crust. Later, this deep portion was affected and involved in alpine and appenninic orogeny. During this phase, a lot of tectonic nappes of different geologic provenience, have been imbricated during thrusts tectonics. The principal line, as a thrust, was the Curinga-Girifalco Line (CGL) that separates the deep crust from other low-grade alpine nappes. The sample’s composition is a set, in equilibrium, of quartz, garnet, sillimanite, k-feldspar and biotite. Knowing the deformation is related to granulitic facies and that garnet deformation, in this P-T conditions, is not widespread (Papa, 2013), we wanted to verify the behavior of this mineral also on a particular microstructure like boudins’ neck. The analysis has been made with SEM, using crystallographic techniques like EBSD and Orientation Contrast. The results show how, in the high temperature condition, the ductile deformation is concentrated in the points where the strain is greater, like necks.