An Integrated Geophysical Investigation of the Flavia Seamount in the Northern Tyrrhenian Back-Arc Basin (Mediterranean Sea)

Despite its geodynamic significance, the northern Tyrrhenian Back-Arc Basin, characterized by a complex tectono-magmatic evolution, remains poorly investigated. We present the first geophysical characterization of the Flavia Seamount, a previously uninvestigated edifice in the northern Tyrrhenian Sea, integrating new multibeam, seismic, and magnetic data. The new high-resolution bathymetric data reveal a flat, nearly circular summit and strongly asymmetric flanks. Reduced-to-the-pole magnetic anomalies exhibit a north–south polarity pattern, with positive values in the northern sector and negative values in the southern sector. Seismic data, integrated with Sparker profiles collected in 1985, reveal a flat-topped acoustic basement overlain by a ~100 m thick stratified sequence and affected by inactive east-dipping extensional faults, indicating tectonic control on the evolution of the seamount. Widespread landslide scarps and associated mass-transport deposits document recurrent gravitational instability along the flanks and within surrounding basins. Pockmark morphometry suggests distinct formation processes, with summit pockmarks controlled by fluid seepage and gravitational processes, and basin pockmarks mainly related to fluid escape from mass-transport deposits. Magnetic forward modelling constrained by seismic data provides new insights into the distribution of magnetic susceptibility bodies and the crustal architecture beneath the seamount. Results suggest that the present-day morphology of the Flavia Seamount reflects the combined effects of tectonic, sedimentary, and gravitational processes.