Earth surface exchanges (ESEX) discussion of ‘Swelling and flow of expanding clays as a cause for nontectonic deformations in a glacial–interglacial environment: Holy Cross Mountains, Poland’ by E. Jurewicz, P. Karnkowski, A. Czarnecka-Skwarek, E. Wójcik, I. Gawriuczenkow. Earth Surface Processes and Landforms 2023: 1–16. https://doi.org/10.1002/esp.5609

Abstract

In a recently published report focused on the role of swelling of Triassic clays as the dominant process that led to the local steepening of competent Jurassic strata, its authors presented an opinion on the lack of evidence for the existence of the Gnieździska–Brzeziny strike-slip fault along the contact between the Triassic and Jurassic rocks. This discussion presents the structural, geophysical, cartographic and geomechanical data indicating that the contact of Triassic and Jurassic rocks is defined by the vertical dextral strike-slip Gnieździska–Brzeziny fault, which was formed after tilting of the beds in the Late Cretaceous. The presented evidence validates the tectonic deformation of Mesozoic rocks related to strike-slip faulting. The dominant horizontal contraction across the fault planes within the restraining stepovers resulted in tilting of the beds, which is a well-recognized phenomenon within the strike-slip fault networks worldwide.