Evolution of Neogene basins and fault systems in the Southern Balkans

The South Balkan region represents a transition zone between oblique continental collision in the Dinarides to the north and rollback subduction of oceanic lithosphere in the Aegean to the south. This tectonic transition has resulted in complex crustal deformation patterns and the formation of numerous sedimentary basins during the Neogene, some still actively extending today. Slab tearing or break-off of the lower plate at depth, as well as interactions with the North Anatolian Fault Zone, have been suggested as possible drivers of the observed crustal deformation. However, the spatiotemporal evolution of deformation and its relation to present-day seismicity and relief of the region remain poorly constrained.  We aim to quantitatively constrain the deformation and paleogeographic evolution of the South Balkan region, in order to assess the relative contributions of slab dynamics and activity along the North Anatolian Fault Zone to upper-plate deformation.

We define the study area between two major tectonic boundaries. In northern Albania and Kosovo, the Shkoder-Peja Fault System (SPFS) marks the boundary between the Dinarides orogen to the north and the Albanide-Hellenide orogen to the south, accommodating a roughly 30° clockwise oroclinal bend related to south-westward retreat of the Hellenic subduction zone. In northern Greece, the Kefalonia Transfer Fault (KTF) separates the Adriatic plate to the north from the Ionian and eastern Mediterranean oceanic lithosphere to the south. While the region south of the KTF and the external part of the Dinarides-Hellenides have been extensively studied, the internal part of the orogen between the KTF and the SPFS has traditionally received less attention.

We conducted an initial field campaign in March 2026, focussing on the sedimentary record of the basins and on evidence of faulting related to basin formation in eastern Albania, North Macedonia and Kosovo. Furthermore, we carried out sampling for cosmogenic nuclides and thermochronology, aiming to better constrain the temporal evolution of erosion rates and fault activity. Here, we present preliminary results, such as a compilation of geophysical, geomorphological, and geological data, including active faults, seismicity, relief, thickness of basin infill, and age of basin formation. We aim to use this integrated approach to study the relationship between present-day seismicity, relief formation and tectonic activity, as well as to quantify basin subsidence and reconstruct the paleogeographic evolution of the region.