Layer-silicates in the contact zone between granite and serpentinite, jordanów, lower Silesia, Poland

Abstract

Abstract Chlorite belonging to subfamily C, vermiculite 2 M B -VII-meso, talc and a monoclinic amphibole were identified in rocks from a contact zone between highly tectonized granite and serpentinite at Jordanów, Lower Silesia, Poland. K-saturated vermiculite readily produced a phlogopite-like structure 1 M -I (3T A -IV) indicating trioctahedral mica to be its precursor. Spatial relations of the mineral assemblages were compared with published experimental data and used to produce a tentative model of the geological evolution of the rocks and minerals, which include four episodes of mineral development separated by three tectonic events.