Polyphase tectonics in the central Salzkammergut (Northern Calcareous Alps, Austria): an updated interpretation

Autor(en)

Nicola Levi

Abstrakt

The Northern Calcareous Alps (NCA) (Austria) consist of detached Austroalpine covers, comprising mainly Permian evaporites and Triassic-Jurassic carbonates, topped by unconformable clastic sediments (Gosau Basin, Late Cretaceous-Eocene). The NCA experienced a polyphase deformation during the Eoalpine phase (Jurassic? mid-Cretaceous) followed by post-Eocene transpressive collisional tectonics. In the study area, the oldest regional structure is the Eoalpine NW-ward thrusting of the Dachstein Unit over the Hallstatt Unit. During the Eocene-Oligocene the dextral WNWENE Wolfgangsee fault developed between Osterhorn and Höllengebirge Units. The top-to-N phase followed (Oligocene?-Early/Mid. Miocene), related to the final emplacement of the Tirolic Units on the Bajuvaric and Rheno-Danubian Flysch, which in the Höllengebirge Unit resulted into intense thrusting and folding related to the Schafberg thrust. In the Middle Miocene the development of the Königsee-Lammertal-Traunsee (KLT) sinistral fault led to the major structures in the area. Two stepped strike-slip sectors (SSW-NNE) and (SW-NE/N-S) delimited a restraining bend, where the WNW-ESE Nussensee thrust and the Weissenbach anticline were formed. This deformation history disagrees with some of the available geodynamic models for the area, providing instead fundamental constrains for the Adria paleogeography and the onset of thrusting in the NCA.

Organisation(en)

Institut für Geologie

Externe Organisation(en)

NiMBUC Geoscience

Journal

Journal of Geodynamics

Band

156

ISSN

0264-3707

DOI

https://doi.org/10.1016/j.jog.2023.101973

Publikationsdatum

06-2023

Peer-reviewed

Ja

ÖFOS 2012

105124 Tektonik

Schlagwörter

ASJC Scopus Sachgebiete

Earth-Surface Processes, Geophysics

Link zum Portal

https://ucrisportal.univie.ac.at/de/publications/9714bdc3-2aae-4544-9788-f6dc5ec2cc85