New paper on the activity of the Periadriatic Fault

The Periadriatic Fault is one of the largest faults in the alpine orogeny, with a main activity onset during the Eocene and Miocene. Currently, the fault has an absence of instrumental seismicity, which, combined with low deformation rates overall in the eastern Alps, hinders the assessment of how active the fault is. However, historical reports indicate it potentially hosted the Mw∼6.6 earthquake in Carinthia from 1690. In a newly published paper, we date the youngest deformation associated with seismic slip in the Pustertal-Gailtal segment of the fault, by employing trapped charged dating methods on fault gouges, directly at the core of the fault. These methods rely on the accumulation of electrons produced by radiation, that accumulate within paramagnetic crystalline defects in quartz and feldspar grains. During fault slip, these electrons may be released by shear heating. Therefore, allowing us to estimate the timing of the last large earthquakes. Our results show that the Pustertal-Gailtal segment of the fault hosted strong earthquakes during the Pleistocene, indicating that the fault has been active for a longer period than it was previously thought.

Prince, E., Tsukamoto, S., Grützner, C., Vrabec. M. & Ustaszewski, K. (2024). Not too old to rock: ESR and OSL dating methods reveal Quaternary activity of the Periadriatic Fault. Earth, Planets and Space, 76:85, doi: 10.1186/s40623-024-02015-6External link OPEN ACCESS!