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In the Chemnitz Basin (Saxony, central Germany), up to 1,500 m thick early Permian sediments with intercalated, predominantly acidic pyroclastics were deposited. Numerous fossil records allow a biostratigraphic correlation of the strata with other early Permian successions of the middle Variscides. Significant floral and faunal elements were found in the Planitz Formation of the Chemnitz Basin, which is bounded at the base by the Grüna Tuff and at the top by the Planitz Ignimbrite. Radioisotopic data are only available for the Planitz Ignimbrite, but they contradict biostratigraphic data. Based on LA-ICP-MS measurements, new U-Pb zircon ages are determined for the Planitz Ignimbrite and, for the first time, also U-Pb zircon ages for the Grüna Tuff. The challenge of deriving an extrusion age for both the Planitz Ignimbrite and Grüna Tuff from these data is discussed. [ABSTRACT FROM AUTHOR]

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]

Copyright of Journal of Applied & Regional Geology / Zeitschrift der Deutschen Gesellschaft für Geowissenschaften (ZDGG) is the property of E. Schweizerbart'sche Verlagsbuchhandlung and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Applied & Regional Geology / Zeitschrift der Deutschen Gesellschaft für Geowissenschaften (ZDGG) is the property of E. Schweizerbart'sche Verlagsbuchhandlung and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Nine radiometric ages constrained by U–Pb isotopes from magmatic zircon grains are provided for different volcanic rocks from the Flöha Basin and its surroundings. For most of them, this is the first reliable data to correlate with the International Chronostratigraphic Chart. Measurements were obtained with LA-ICP-MS and revealed middle Pennsylvanian ages (311–308 Ma) allowing first consistent correlation to other Variscan volcano-sedimentary basins of the Saxo-Thuringian and Teplá Barrandian zones. The Obermühlbach Volcano, formerly considered to be early Permian in age, is shown to be of middle Pennsylvanian age. In contrast, the dykes from Metzdorf village and Oederan have shown to be not Pennsylvanian, but rather of early Permian age. Biostratigraphic data obtained from the Flöha Formation macroflora coincide with the new isotopic evidence which encompasses a likely time span from the middle to late Bolsovian (Westphalian C) up to the Bolsovian–Asturian boundary. The results not only yield a modified picture of the Flöha Formation and their intercalated pyroclastics. As new insights challenge previous geological mapping they contribute to the understanding of the complex volcano-tectonic processes in the type area of the Saxo-Thuringian zone of the European Variscides. [ABSTRACT FROM AUTHOR]