Buried fault and 13 foot scarp reveal ancient quakes in southern Poland
Feb 22nd 2026
Geomorphologists mapped a straight 2 mile soil scarp near Brzegi, traced it to a previously unknown fault, and dated a rupture to 10,000 to 50,000 years ago using trenching and diffusion modeling.
- A 13 foot high scarp runs about 2 miles across pastures near Brzegi in the Podhale basin north of the Tatra Mountains.
- Piotr Kłapyta of Jagiellonian University led mapping that linked the surface scarp to a previously unknown fault.
- Airborne laser mapping and shallow geophysical surveys traced a continuous straight edge and a sharp underground discontinuity beneath it.
- A paleoseismic trench exposed abrupt offsets and sheared sediment consistent with sudden fault motion rather than slow slumping.
- Diffusion modeling of the scarp surface gives a rough age range for the rupture of about 10,000 to 50,000 years ago.
- The finding shows large earthquakes affected the area long before modern seismometer records and historical accounts.
- Authors say more trenches and better dating are needed to determine recurrence rates and revise regional hazard assessments.