The Southern Apennine front: evidences of recent activity at the Gulf of Taranto (Italy).

The Southern Apennines collisional belt is connected to the Calabrian Arc subduction system across the Gulf of Taranto area (Southern Italy). The role of active deformation during the late Pleistocene-Holocene time is a matter of debate. Our research focused on the feeding area of the Taranto Canyon, the main morphological feature of the continental slope in the study area. The headwall canyon incises the continental margin from the shelf break, at about 30 m b.s.l., down to 450 m depth, covering an area of about 50 km². A novel, high-resolution multibeam bathymetry was acquired using a Multibeam Echo-Sounder system. A total of approximately 1600 km² of high-resolution bathymetric data were collected, with a final gridded resolution of 10 × 10 m, referenced to Mean Sea Level. Bathymetry was used to generate a Digital Elevation Model (DEM), allowing reliable morpho-structural and hydrographic analysis. In addition, a total of 650 km of seismic lines were collected across the outer continental shelf and slope in the north-eastern sector of the Gulf of Taranto, using the GeoResources Geo Spark 200 Sparker system, operating at 1 kJ. The adopted configuration allowed a dominant frequency range between 500 and 2000 Hz, a pulse length of ~0.5 ms, allowing imaging depths between 200 and 400 ms, two-way travel time. These acquisition parameters ensured a high-resolution imaging of buried sedimentary units, stratigraphy and tectonics. The interpretation of seismic sparker profiles, along with the high-resolution bathymetry, reveal deformations and small-scale thickness variations within Pleistocene–Holocene units. The integration of morphostructural and geophysical data suggests that present-day deformation exerts a primary control on canyon evolution and slope dynamics of the north-eastern Gulf of Taranto. These results provide new insights into the recent geodynamic evolution of the Southern Apennine front and highlight its implications for potential geohazard assessment.