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Submarine landslides are an ubiquitous process along the continental margins of the Mediterranean Sea. A database, containing 232 occurrences of mass failure deposits and 211 occurrences of failure scars, has recently been compiled from publicly available literature indicating that submarine landslides in the Mediterranean occur on tectonically dominated margins as well as on passive margins and volcanic island flanks. The record is relatively rich in the European margins and relatively poor in the North-African margins indicating that further studies are necessary in the southern Mediterranean so as to obtain an inventory that might be useful for geohazard evaluation. Most landslides occur in the form of long distance travelling debris flows, but slumps and deep seated failures are also relatively common. On abyssal plains the distal product of massive failures is recorded as large megaturbidites, while on volcanic islands the dominant failure type are debris avalanches, owing to the rocky nature of their flanks. Submarine landslides, excluding megaturbidites, appear to occur on all water depth between the coastline and about 2000 m. No submarine landslides were recorded beyond that depth. Most landslides occupy areas ranging from a few squared km to about 600 km2 and volumes up to 220 km3, but massive abyssal plain megaturbidites can attain 60,000 km2 and 1000 km3. The headwalls are clustered around two modes: 0 to 40 m for relatively small landslides and 160 to 200 m for the largest ones. Most recorded submarine landslides are relatively young in age and several events appear to group near the Pleistocene to Holocene transition, indicating that a climatic control in triggering seems plausible. 50 events were reported to occur in areas were slope instability is a recurrent process, 20 events were reported as tsunami initiators. This study indicates that submarine slope instability is one of the most important processes operating on continental margins and poses a significant geohazard. Further studies are thus requested in order to characterize this process including drilling and monitoring of a few places were failure seems to be at an initial stage.
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