An evidenced high velocity area living in the SE Tyrrhenian Basin has been interpreted by tomographic studies as the Ionian slab subducting toward NW [Cimini(1999)], [Cimini(2004)], [Lucente et al.(1999),Montuori (2004)]. The slab shows an evident vertical continuity with high dipping angles (70°-75°) down to 400 Km depth, and lateral extensions of 200 Km deeper than 150-200 Km and 100 Km above [Montuori (2004)]. Low velocity zones are present along the whole vertical extension of the high velocity zone, being interpreted as asthenospheric fluxes or convective cells generated by the subducting plate. The coincidence between the observed low velocity zone and the morphology of Aeolian Arc indicates that subduction was able to generate the regional volcanism.
The Aeolian Arc, part of the arc-trench system resulting by the collision of the African and Eurasian plate [Barberi et al.(1974)] , is a 200 Km volcanic structure, located on the inner margin of the Calabro-Peloritano Arc. It is active since 1.3 MY on the western portion and it is formed by 7 subaerial (Alicudi, Filicudi, Salina, Lipari, Vulcano, Panarea e Stromboli) and several submarine volcanoes surrounding the Marsili Basin (Figure 1). Present activity is located on the eastern portion (Vulcano, Lipari, Panarea, Stromboli).
Stromboli (924 m a.s.l., 12.6Km
) is the northernmost Aeolian Island. It is a stratovolcano which rises about 3000 m from the seafloor and stands 924 m above the sea level (Figure 2).
The products continuously erupted by the Stromboli volcano onlap on its submarine flanks, and are often subject to gravitational instabilities (mass gravity flows, debris flows, debris avalanches, slides, rock falls, erosion on channels and slumpings), producing lineaments, that were also observed and mapped by TOBI Side Scan Sonar data (TIVOLI cruise, a joint research project between University of Roma "La Sapienza" , CNR-IAMC of Naples, Italy and CNR-ISMAR of Bologna, Italy [Chiocci et al.(1998)]). The eastern sector of the island shows a large chute of detritus, triggered by channelised debris fluxes organized as large-scale sea bottom features perpendicular to the isobaths. The northwestern sector is occupied by the submarine continuation of the "Sciara del Fuoco", extending for several kilometers before joining laterally the Stromboli canyon, one of the most important canyons of the Southern Tyrrhenian sea, that connects NE Sicilian landforms with the bathyal plain running around the Aeolian arc. The canyon is fed by channelised fluxes on its right flank (between them the Gioia canyon) and mass fluxes on its left flank, including submarine instability products from Stromboli, where its thalweg approaches the island.
The volcanic edifice [Di Fiore et al. (2006)] was recently considered to be similar to the Campanian volcanoes, with well developed, 10-15 Km thick, low-velocity strata and a thin continental crust superimposed [Panza et al.(2004)]. The polyphasic eruption activity [Beccaluva et al.(1985)] intercalated lava strata (high velocity, 2500-4000 m/s) to pyroclastic, explosive products strata (P wave velocity 300-800 m/s), causing strong vertical and horizontal velocity gradients. Seismic tomography inversion, requiring high energy and large number of recording stations is probably the best method for investigating these anomalies.