The Sava Fault is a ~150 km long fault of the Periadriatic Fault System. It is located in the south‑eastern Alps, in the compressive to transpressive contact zone between the Adriatic microplate and the Eurasian plate and has been active since at least the last 6 Ma. Despite its known seismic potential, the fault’s seismic history has not yet been studied, therefore an appropriate site for palaeoseismological investigation must be identified.
This master’s thesis investigates the structure of the Sava Fault near the village of Gozd above Golnik. A detailed structural‑geological map was produced, the area was surveyed photogrammetrically, and various visualisations of digital elevation models were analysed. Geophysical measurements (electrical resistivity tomography) were carried out across the fault and the Quaternary sediments covering it were sedimentologically described and dated using radiocarbon analysis. The resulting structural‑geological map reveals Triassic carbonates of the Schlern Formation, Oligocene marls, claystones and andesitic tuffs, Pleistocene diamictons and diamictites, Holocene diamictons and Holocene gravelly‑sandy sediments. The trace of the main branch of the Sava Fault, trending NW–SE, and of numerous secondary faults running alongside it were identified. Geomorphic analysis of various digital elevation model visualisations shows that the village of Gozd lies on a levelled surface covered by Quaternary sediments deposited as alluvial fans. Electrical resistivity tomography confirmed the fault as a subvertical low‑resistivity zone and revealed deformation of the Quaternary sediments, demonstrating its Quaternary activity. Detailed descriptions of sedimentary units in the excavation pit and radiocarbon dating of charcoal (4–42 ka) indicate predominantly slow accumulation of fine‑grained colluvium with a single high‑energy debris deposition event in the distal part of the fan. Synthesis of the acquired data implies that the village of Gozd lies on a large structural landslide, likely triggered in the Early to Middle Pleistocene (about 1 Ma to 500 ka) and since then offset for 200-500 m along the fault. The results provide new insights into the geological structure of the Sava Fault near Gozd, highlight the interaction between tectonic and gravitational processes, and provide a basis for further palaeoseismological research.
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