Tectonics of eastern Sicily offshore: preliminary results from the MESC 2001 marine seismic cruise

The Malta Escarpment represents the dominant morphological feature offshore eastern Sicily and appears as a steep, eastward-sloping surface partly onlapped by the flat laying sediments of the adjacent Ionian Basin. Both tectonic structures and seismicity indicate a peculiar neotectonic activity along the eastern Sicilian slope. In order to investigate the neotectonics of this region, a multi channel seismic survey (MESC 2001) was carried out on the eastern Sicilian slope. The Malta Escarpment can be divided into two portions characterised by different tectonic structures. Along the segment south of Siracusa, the Malta Escarpment is not affected by recent faulting and appears as a steep surface that flattens out towards the Ionian Basin. The escarpment appears as an original slope, likely inherited from Mesozoic (or earlier) times, linking the deep Ionian Basin to the east with the Hyblean carbonate platform to the west. A recent deformation, characterised by a broad area of uplift, occurs 20-30 km east of the slope, along a NNW-SSE trend. The segment of the Malta Escarpment extending north of Siracusa, on the other hand, is characterised by the presence of NNW-SSE, east-dipping recent extensional faults located along the morphological escarpment and a few km east of it. In some instances, splays of the western extensional faults join the sloping surface of the Malta Escarpment, whereas the easternmost extensional faults, and related sedimentary basins, are affected by contractional deformation.