Seafloor morphology and recent dynamics in the Scoglio d'Affrica (Northern Tyrrhenian Sea)

From 2017 to 2023, the offshore area nearby the Scoglio d’Affrica islet, located in the Northern Tyrrhenian Sea, has been surveyed and monitored after a violent fluid emission from a shallow-water mud volcano that caused an outburst rising 10 m above the sea surface. This transient phenomenon occurred very localized and short-lived. Assessing the complexity of this kind of event requires an integrated monitoring system, which allows us to characterize the seafloor morphology and recent dynamics through high resolution swath bathymetry and direct visual seafloor observation. These data allow also the identification of new features produced by recent seafloor dynamics and fluid seepage related to mud volcanism, obtaining insights on the temporal and spatial evolution of the seafloor morphology related to cold seeps in the area. In particular, the mud volcano responsible for the 2017 gas outburst is made up of two shallow water mounds characterized by different seafloor evolutionary records, including sediment consolidation, fracturing and variation in morphology and height, likely related to inflation/deflation processes as well as to the sediment reworking by wave action.