Using quantitative seafloor geomorphology to unravel the deformation of Eratosthenes Seamount at the verge of subduction

The bending of a subducting plate leads to extension in its upper crust through faulting. The geometry of these faults represents the convergence orientation (i.e., normal or oblique). The Eratosthenes Seamount (ESM) in the eastern Mediterranean is a natural laboratory for unraveling the tension of a subducting plate. While most of the basin is covered by extensive sedimentation that obscures the faulting pattern, ESM stands out above its surrounding relief and provides a window into the faulting pattern close to the subduction trench of the Cyprus Arc. Previous studies provided reliable sedimentologic, structural, and tectonic constraints for ESM development and incipient collision with the Cyprus arc. However, the lack of high-resolution bathymetric data prevented its quantitative geomorphological analysis. The present study analyses the bathymetry of ESM and its surrounding trench and encircling cliffs through geomorphological and statistical methods. Results show that fault orientations and extensional nature confirm previous indications of tension across the bending plate. Nonetheless, it challenges the claim for incipient collision. The pattern and distribution of slope channels and slides attest to ongoing directional instability despite the lack of an immediate sediment source. Combined analysis of the seamount and cliffs indicates an overall northward tilt that developed since the early Pliocene.