Raised Holocene paleo-shorelines along the Capo Schiso coast, Taormina: New evidence of recent co-seismic deformation in northeastern Sicily (Italy)

Detailed mapping of geomorphological, biological and archaeological sea-level markers around the Capo Schiso volcanic headland, a few kilometers south of Taormina, north-eastern Sicily, has documented the occurrence of three Holocene paleo-shorelines raised at different altitudes. The uppermost shoreline (PS1) is represented by a fossiliferous beach deposit that is heavily eroded and only few small sections, at elevations ranging between similar to 3 and similar to 5 m above the present sea-level, are visible. The middle shoreline (PS2) was found at a maximum altitude of similar to 3 m and is represented by algal rims, remnants of barnacle bands and vermetid concretions, and by a fossiliferous beach deposit. The lowermost shoreline (PS3) includes remnants of algal rims, vermetid concretions, fossil barnacle bands and a beachrock, and reaches an elevation of 1.60-1.80 m. New radiocarbon dating results, integrated with published ages from nearby paleo-shoreline outcrops, constrains for the Taormina region an average uplift rate of 1.7-1.8 mm/yr in the last 5 ka, and the occurrence of three co-seismic uplift events at 4.4-3.9 ka, 2.1-1.8 ka and <= 1.0 ka ago. Abrupt displacements are tentatively attributed to footwall uplift along an offshore normal fault, but further investigations are needed to better constrain the causative source of past earthquakes. Notwith-standing, based on coastal tectonic analysis, this paper provides a new assessment of age and recurrence time of Holocene earthquakes in a historically strong seismogenic area. (C) 2011 Elsevier Ltd. All rights reserved.