Tectonometamorphic features of geological units along the northern periphery of the Moldanubian Zone (Bohemian Massif)

In this paper are reviewed structural, petrological and geochronological data from the main units at the NE periphery of the Moldanubian Zone, i.e. Kutna Hora Complex, Svratka Unit, Policka and Zabreh units, as well as the Strazek Unit of the Moldanubian Zone. In this domain of the Bohemian Massif, the lower- and upper-crustal units are dominated by metamorphic fabrics produced during the Variscan orogeny. The mid- to upper-crustal Svratka, Policka and Zabreh units are affected by similar to MP/MT long-lived (similar to 350-339 Ma) tectonometamorphic event reflecting similar to WNW-ESE right-lateral strike-slip shearing (transpressional to transtensional tectonics). These regional fabrics are in the Policka and Zabreh units related with syn-tectonic emplacement and crystallization of calc-alkaline intrusions (Zabreh Intrusive Complex, Miretin nad Budislav plutons). In the three structurally high units in the Kutna Hora Complex, Orlice-Sneznik and the Strazek units the strike-slip, long-lived tectonics is rather localized; the high-pressure, high-temperature events followed by heterogeneous and polyphase exhumation of deep-seated rocks to mid-crustal levels are preserved. Ultrapotassic rocks (durbachites) of the Strazek Unit, dated at similar to 339 Ma, intruded posttectonicaly.