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This study presents novel findings on the Pliocene and Quaternary evolution of the Gela Basin (Strait of Sicily, Mediterranean Sea), an area recording the interaction between tectonics, climate change at a Milankovitch and sub-Milankovitch timescales, and dynamic water masses exchange between the eastern and western Mediterranean Sea. The calibration of seismic profiles with exploration boreholes allowed for the refining the chronostratigraphic framework of the Gela Basin and highlighted the main phases of margin growth. Since the Pliocene, the margin has recorded the deposition of 100 m high shelf-edge clinothems, accompanied by sediment drifts on the slope and mass-transport deposits (MTDs), possibly triggered by seismic activity. Through the Plio-Quaternary the locus of deposition of sediment drifts migrated upslope due to a progressive shift of bottom currents. After the Middle Pleistocene Transition (MPT) the margin experienced an accelerated outbuilding with the deposition of a 700 m thick succession in only 0.8 Myr. At this time, a marked change in sedimentary architecture reflects the growth of shelf-edge clinothems and associated MTDs on the slope, and the spreading of contourite deposits over a broader and generally shallower area. Sediment flux to the basin and the intensity of bottom currents appear both paced at 100 kyr eccentricity orbital cycles. The growth of bottom current deposits on a large portion of the upper slope and outer shelf likely reflects constraints to the bottom current flow by the margin morphology, inherited from Miocene and Pliocene tectonics. Overall, a combination of long-term tectonic activity, climate change and shifts in oceanographic regime resulted in a complex along-strike variability of the margin morphology and stratigraphic architecture and affected where and when MTDs were emplaced. These conclusions show how climate cyclicity influence sediment supply which combined with margin morphology can promote slope instability i

This thesis (SLATE-project, https://www.itn-slate.eu/) is concentrated on submarine landslides in the central Mediterranean Sea. Commonly found in marine and lacustrine environments, submarine landslides represent one of the main mechanisms of sediment transport along continental margins, their volumes can be far larger than any terrestrial landslides and have potential to produce far-reaching tsunamis that can rival those produced by earthquakes. However, many uncertainties remain concerning their preconditioning factors, triggering mechanisms, return frequencies and relationship with climate change as well as their geohazard potential, which vary depending on their location. Newly identified submarine landslides emplaced in the Gela Basin (GB; south of Sicily, central Mediterranean Sea) were investigated where the particular geodynamic and oceanographic context and the limited extent basin is ideal for submarine landslides research. The investigation through multiple data types including deep boreholes, multi-channel and subbottom seismic profiles, sediment cores and swath bathymetry revealed the emplacement of multiple submarine landslides during the margin outbuilding in the Pliocene-Quaternary with a drastic transition in their volumes and emplacement location at the Middle-Pleistocene Transition (MPT). This change, accompanied by an accelerated margin outbuilding from 150 to 900 m/kyr and growth of the contourite deposits, has been related to the decreasing tectonic activity at the southern front of the Maghrebian fold-and-thrust belt and the climatic changes linked to the switch to the 100-kyr Milankovitch cyclicity. Numerical in-house codes used for the reconstruction of two small-size MTDs located at the ends of the GB show similar potential of generating high-wave tsunamis that can impact the coasts of Malta and Sicily but different triggering mechanisms based on the stability analysis. A multiproxy approach made on the sediment cores revealed that strong

This thesis (SLATE-project, https://www.itn-slate.eu/) is concentrated on submarine landslides in the central Mediterranean Sea. Commonly found in marine and lacustrine environments, submarine landslides represent one of the main mechanisms of sediment transport along continental margins, their volumes can be far larger than any terrestrial landslides and have potential to produce far-reaching tsunamis that can rival those produced by earthquakes. However, many uncertainties remain concerning their preconditioning factors, triggering mechanisms, return frequencies and relationship with climate change as well as their geohazard potential, which vary depending on their location. Newly identified submarine landslides emplaced in the Gela Basin (GB; south of Sicily, central Mediterranean Sea) were investigated where the particular geodynamic and oceanographic context and the limited extent basin is ideal for submarine landslides research. The investigation through multiple data types including deep boreholes, multi-channel and subbottom seismic profiles, sediment cores and swath bathymetry revealed the emplacement of multiple submarine landslides during the margin outbuilding in the Pliocene-Quaternary with a drastic transition in their volumes and emplacement location at the Middle-Pleistocene Transition (MPT). This change, accompanied by an accelerated margin outbuilding from 150 to 900 m/kyr and growth of the contourite deposits, has been related to the decreasing tectonic activity at the southern front of the Maghrebian fold-and-thrust belt and the climatic changes linked to the switch to the 100-kyr Milankovitch cyclicity. Numerical in-house codes used for the reconstruction of two small-size MTDs located at the ends of the GB show similar potential of generating high-wave tsunamis that can impact the coasts of Malta and Sicily but different triggering mechanisms based on the stability analysis. A multiproxy approach made on the sediment cores revealed that strong