EGU22-3790, updated on 27 Mar 2022
EGU General Assembly 2022
© Author(s) 2022. This work is distributed under
the Creative Commons Attribution 4.0 License.

Quaternary paleostress regimes in the Eastern Alps inferred from ruptures in karst caves

Ivo Baroň1, Jacek Szczygieł2,3, Rostislav Melichar4, Lukas Plan5, Bernhard Grasemann3, Eva Kaminsky6, and Denis Scholz7
Ivo Baroň et al.
  • 1Institute of Rock Structure and Mechanics, The Czech Academy of Sciences, Prague, Czech Republic (
  • 2Institute of Earth Sciences, University of Silesia in Katowice, Sosnowiec, Poland (
  • 3Department of Geology, University of Vienna, Vienna, Austria
  • 4Department of Geological Sciences, Masaryk University, Brno, Czech Republic
  • 5Departament of Geology and Paleontology, Natural History Museum, Vienna, Austria
  • 6Institute for Soil Physics and Rural Water Management, University of Natural Resources and Life Sciences (BOKU), Vienna, Austria
  • 7Institute for Geosciences, Johannes Gutenberg University, Mainz Germany

In the Alps, the Adriatic plate convergence provoked eastward lateral extrusion compensated by strike-slip faulting and N-directed thrusting. Since the Miocene, these complex processes have led to several paleostress phases. Since the Quaternary phase is the least recognized, we used karst cave passages as the geomorphic displacement indicators. This study presents an overview of 190 Quaternary fault ruptures in totally 27 caves in the Eastern Alps, some radiometrically dated, and the paleostress analysis based on cave passages offset. Reactivated faults have been registered with their orientation, slip vector and offset, in caves adjacent to major fault systems of the Eastern Alps. The paleostress was computed using the multiple inversion method for heterogeneous fault-slip data.

Most active faults in caves along the southern part of the sinistral Vienna Basin Transfer Fault were NW-SE, and NNE-SSW oriented and revealed mostly normal to sinistral kinematics and cumulative offsets of a few mm to a couple of cms. The associated extensional paleostress state comprised the E-W σ3 in agreement with the opening mode of the Vienna Basin. At sinistral Mur-Mürz Fault, the active faults striking NNE-SSE and ENE-WSW operated under a strike-slip regime with σ1 NE-SW. In the eastern segment of sinistral Salzach-Ennstal-Mariazell-Puchberg fault associated strike-slip paleostress regime with horizontal SE-NE σ1, and subhorizontal SE-trending σ3. This stress regime was computed from reverse, oblique reverse, oblique normal, and sinistral strike-slip reactivated faults documented in the Hochschwab massif. The central segment of Salzach-Ennstal-Mariazell-Puchberg fault is adjoin to Totes Gebirge and Dachstein massifs. In the western part of Totes Gebirge, three stress regimes were recorded. N-S and NW-SE striking oblique normal strike-slip faults revealed an extensional regime with NE σ3. Two strike-slip regimes with NE-SW σ1 and subhorizontal σ3 gently inclined to SE and NW were calculated from mostly steep oblique reverse NNE to NW striking faults with offsets up to a few decimetres. In the Dachstein massif, two paleostress phases were identified: the extensional regime with σ3 subhorizontally tilted to NE and the strike-slip regime with N-S σ1. Tens of active, mostly oblique normal strike-slip faults were documented in massifs adjacent to sinistral Königsee-Lammertal-Traunsee Fault: Hoher Göll, Tennengebirge and Hagengebirge. The dominating associated paleostress is an extensional regime with NE-SW σ3. The polyphase sinistral and reverse-dextral NE-SW faults with Late Pleistocene to Early Holocene reactivations and up to 40 cm offsets, identified at the sinistral Obir Fault attributed to the dextral Periadriatic Line. Neither the strike-slip regime with ENE-plunging σ1 nor the other strike-slip regime with σ1 WNW oriented to fit the regional stress setting. It probably resulted from large-scale complex Karawanken Mts. transpressive shear zone deformation.

In conclusion, the paleostress multiple inversions from the Quaternary cave passage ruptures kinematic data brought original information on the paleostress regime over a significant portion of the Eastern Alps in their latest deformational period.

How to cite: Baroň, I., Szczygieł, J., Melichar, R., Plan, L., Grasemann, B., Kaminsky, E., and Scholz, D.: Quaternary paleostress regimes in the Eastern Alps inferred from ruptures in karst caves, EGU General Assembly 2022, Vienna, Austria, 23–27 May 2022, EGU22-3790,, 2022.