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Abstract

The Saxo-Thuringian Zone is pivotal for understanding the Variscan evolution of Central Europe, as this part of Gondwana was one of the first to collide with Laurussia. The Saxo-Thuringian Zone comprises domains that have experienced variable degrees of Variscan metamorphism ranging from medium grade to UHT/UHP in some domains, while other parts were largely unaffected by deformation or metamorphism. These differences in overprint reflect pre-Variscan crustal heterogeneity and thickness variation, where thinner segments were wedged into the subduction zone and rigid, thicker blocks escaped subduction. The heterogeneity of crustal thickness is considered to be caused by Ordovician rifting (470-480 Ma) of the Cadomian crust (570-540 Ma) at the Gondwana margin. Today, magmatic and sedimentary rocks deposited on the thin crust of these rifts form the metamorphic complexes of the Saxon Granulite Massif and the Erzgebirge Mtns. Variable response of crust of different thickness to Variscan deformation and metamorphism is not particular to the Saxo-Thuringian Zone, but rather a typical feature of the crust all over Variscan Europe. The 18 chapters of this book are review and synthesis papers and present overviews of the Cadomian evolution, the post-Cadomian development of the passive margin, a state of the art assessment of the biostratigraphic record of Saxo-Thuringian sediments, various aspects (metamorphism, structure, magmatism) of the Variscan reworking of the Saxo-Thuringian Zone and processes related to the erosion of the Variscan Orogen. Extensive references include also older, generally difficult to find literature references, PhD theses and original descriptions published in very local journals. This book makes use of, and in part provides, previously unavailable maps and borehole data, largely acquired in GDR time in the course of exploration for uranium, fossil fuels, and ore minerals. The geological sheet map of the Pre-Permian geology of Eastern Germany, based on this material and compiled by SDAG Wismut (now WISMUT GmbH), is included and made available for the first time to a wider audience. Numerous figures and additional materials are provided on the enclosed DVD.