Carboniferous--Permian volcanic evolution in the mid-European Variscides: U-Pb LA-ICP-MS zircon ages, geochemical and petrographical constraints from the NW Saxonian Volcanic Basin (Germany).

U-Pb isotope ages from magmatic zircon grains are provided for different volcanic rocks of the NW Saxonian Volcanic Basin within the Rochlitz and Wurzen volcanic systems. Measurements were obtained with LA-ICP-MS and revealed late Pennsylvanian to early Cisuralian ages (301-299 Ma). For the Rochlitz Volcanic System supereruption, we present for the first time a radiometric age consistent with biostratigraphic evidence. We report geochemical data for the Gnandstein Andesitoid, the Dölitzsch, Rüdigsdorf, Rochlitz and Wolftitz tuffs and the Rochlitz-α Ignimbrite. The results yield a modified picture of the Kohren, Rochlitz and Oschatz formations as well as new insights into the understanding of the complex volcano-tectonic processes of the NW Saxonian Volcanic Basin, an area of the Saxo-Thuringian Zone of the European Variscides. [ABSTRACT FROM AUTHOR]