Geologie, Geochemie und LA-ICP-MS U-Pb-Alter jungpaläozoischer Eruptionszentren am NW-Rand des Erzgebirges (Sachsen) – Der Obermühlbach-Vulkan

Research output: Contribution to journalResearch articleContributedpeer-review

Contributors

  • Frank Löcse - , Museum für Naturkunde - Leibniz Institute for Evolution and Biodiversity Science (Author)
  • Jochen Rötzler - , Helmholtz Centre Potsdam - German Research Centre for Geosciences (Author)
  • Birk Härtel - , Freiberg University of Mining and Technology (Author)
  • Ulf Linnemann - , Senckenberg Gesellschaft für Naturforschung (Author)
  • Gitta Schneider - , Freiberg University of Mining and Technology (Author)
  • Ronny Rößler - , Museum für Naturkunde - Leibniz Institute for Evolution and Biodiversity Science, Freiberg University of Mining and Technology (Author)

Abstract

The correlation of late Palaeozoic eruption centres situated at the northwestern margin of the Erzgebirge (Saxo-thuringian Zone, Germany) with the regional post-Variscan magmatism has as yet remained unresolved. Our study focuses on the petrography, geochemistry, and the formation age of the Obermühlbach volcano as one of these eruption centres. The outcropping and drilled, potassium-rich, volcanic rocks originate from a highly differentiated, calc-alkaline, peraluminous A-type granitic melt with intra-plate signature. The Obermühlbach tuff bear strong geochemical similarity to the Lower Permian Zeisigwald tuff in the near-by Chemnitz Basin. LA-ICP-MS U-Pb zircon dating of the Obermühlbach tuff and rhyolite clasts contained therein has yielded ages of 302.8 ± 3.8 Ma and 314.6 ± 2.4 Ma, respectively. Zircon saturation models suggest a temperature range of 750–800 °C for zircon crystallisation in the subvolcanic Obermühlbach rhyolites, and of ~840 °C in rhyolite clasts intercalated within the Obermühlbach tuff. The Obermühlbach tuff itself records zircon saturation temperatures in both aforementioned temperature ranges, based on different samples. The rhyolite clasts and the vol-canic/sub-volcanic rocks of the Flöha Basin are similar in petrography and geochemistry. The new evidence allows a better understanding of the evolution of the Obermühlbach volcano and discloses its correlation with the regional Permo-Carbon-iferous magmatism.

Translated title of the contribution
Geology, geochemistry and LA-ICP-MS U-PB ages of late palaeozoic eruption centres at the NW margin of the erzgebirge (Saxony) – The Obermühlbach volcano.

Details

Original languageGerman
Pages (from-to)443-480
Number of pages38
JournalZeitschrift der Deutschen Gesellschaft fur Geowissenschaften
Volume171
Issue number4
Publication statusPublished - Oct 2020
Peer-reviewedYes
Externally publishedYes

Keywords

ASJC Scopus subject areas

Keywords

  • Erzgebirge, Geochemistry, Geochronology, Late Carboniferous, Lithostratigraphy, Rhyolite