The Austro-Alpine Metamorphic Basement East of the Tauern Window

Abstract

The Austro-Alpine metamorphic basement eastofthe Tauern window contains various tectono-stratigraph-ic units which are highly diverse with respect to pro-tolith and metamorphic ages and also geodynamic environment of formation. Early Precambrian elements are represented in certain units, by detrital minerals or possible magmatic rocks. The continuous history started with Late Proterozoic to Cambrian island arc and ophiolite sequences, which were accreted during Late Cambrian and Ordovician tectono-thermal events. These are overlain by fossiliferous Silurian-Devonian shelf sequences. The shelf sequence is contrasted by the Silurian to Devonian active continental margin with partly S-type granite magmatism. Final collision of all units occurred during the Early Carboniferous, involving deep-crustal thrusting, metamorphism, col-lisional-type magmatism, and subsequent uplift. Sedi-mentary overstep sequences were deposited at different times from the Early Carboniferous to the Permian, and indicate the progradation of the deformation front within the internal Variscan belt.