Giovanni Scicchitano

Tsunami and storm deposits preserved within a ria-type rocky coastal setting (Siracusa, SE Sicily)

Sedimentological and palaeoecological observations, accompanied by archaeological determinations and absolute dating, have been carried out on a recent beach-barrier system succession located 20 km south of Siracusa, south-eastern Ionian coast of Sicily (Italy). Th ese deposits fi ll the back edge of a ria incised within Miocene limestones and are composed of three main stratal units characterized by distinct sedimentological features. Th e two lower units, formed by crossbedded sands and laminated clays, recorded the development of a small confi ned beachbarrier depositional system, infl uenced by frequent high-energy events. Th e upper unit, represented by chaotic coarser sediments, can be attributed to a destructive marine high-energy event. Th e physical properties of the composing stratal units and the morphological setting of the study area allowed us to reconstruct a suite of stormand tsunami-related marine depositional processes that might have occurred in recent times along this area of elevated seismicity. In particular, absolute dating and archaeological determinations allow correlating the upper unit to a tsunami wave triggered by the 1693 AD catastrophic earthquake. Th e same depositional mechanism can also account for some of the coarse levels occurring into the underlying stratal units.

Terrestrial Laser Scanner techniques in the assessment of tsunami impact on the Maddalena peninsula (south-eastern Sicily, Italy)

The coastline of the Maddalena peninsula (south-eastern Sicily, Italy) is characterised by the occurrence of a boulder field associated to an extended soil stripping area and by a gravel/sandy berm. The accumulation of the boulders has been mostly correlated to the impact of the December 28, 1908 tsunami wave. The use of Terrestrial Laser Scanner survey techniques, associated to Differential Global Position System determinations, permits to obtain new data for the assessment of tsunami impact on this coastal area. The computing of the surveyed data using the most recent equations is a useful tool in order to estimate the theoretic inundation limit and to reconstruct its variability in function of the boulders size and of the coastal topography. Moreover, the entire new data set allows to confirm that the hypothesis of the tsunami impact is the most reasonable to explain the occurrence of boulders weighing up to 50 tons on the Maddalena peninsula.

Timing of the emergence of the Europe–Sicily bridge (40–17 cal ka BP) and its implications for the spread of modern humans

Abstract The submerged sill in the Strait of Messina, which is located today at a minimum depth of 81 m below sea level (bsl), represents the only land connection between Sicily and mainland Italy (and thus Europe) during the last lowstand when the sea level locally stood at about 126 m bsl. Today, the sea crossing to Sicily, although it is less than 4 km at the narrowest point, faces hazardous sea conditions, made famous by the myth of Scylla and Charybdis. Through a multidisciplinary research project, we document the timing and mode of emergence of this land connection during the last 40 kyr. The integrated analysis takes into consideration morphobathymetric and lithological data, and relative sea-level change (both isostatic and tectonic), resulting in the hypothesis that a continental land bridge lasted for at least 500 years between 21.5 and 20 cal ka BP. The emergence may have occurred over an even longer time span if one allows for seafloor erosion by marine currents that have lowered the seabed since the Last Glacial Maximum (LGM). Modelling of palaeotidal velocities shows that sea crossings when sea level was lower than present would have faced even stronger and more hazardous sea currents than today, supporting the hypothesis that earliest human entry into Sicily most probably took place on foot during the period when the sill emerged as dry land. This hypothesis is compared with an analysis of Pleistocene vertebrate faunas in Sicily and mainland Italy, including a new radiocarbon date on bone collagen of an Equus hydruntinus specimen from Grotta di San Teodoro (23–21 cal ka BP), the dispersal abilities of the various animal species involved, particularly their swimming abilities, and the Palaeolithic archaeological record, all of which support the hypothesis of a relatively late land-based colonization of Sicily by Homo sapiens.

Integrating multidisciplinary instruments for assessing coastal vulnerability to erosion and sea level rise: lessons and challenges from the Adriatic Sea, Italy

The evolution of coastal and transitional environments depends upon the interplay of human activities and natural drivers, two factors that are strongly connected and many times conflicting. The urge for efficient tools for characterising and predicting the behaviour of such systems is nowadays particularly pressing, especially under the effects of a changing climate, and requires a deeper understanding of the connections among different drivers and different scales. To this aim, the present paper reviews the results of a set of interdisciplinary and coordinated experiences carried out in the Adriatic Sea (north-eastern Mediterranean region), discussing state-of-the art methods for coastal dynamics assessment and monitoring, and suggests strategies towards a more efficient coastal management. Coupled with detailed geomorphological information, the methodologies currently available for evaluating the different components of relative sea level rise facilitate a first identification of the flooding hazard in coastal areas, providing a fundamental element for the prioritization and identification of the sustainability of possible interventions and policies. In addition, hydro- and morpho-dynamic models are achieving significant advances in terms of spatial resolution and physical insight, also in a climatological context, improving the description of the interactions between meteo-oceanographic processes at the regional scale to coastal dynamics at the local scale. We point out that a coordinated use of the described tools should be promptly promoted in the design of survey and monitoring activities as well as in the exploitation of already collected data. Moreover, expected benefits from this strategy include the production of services and infrastructures for coastal protection with a focus on short-term forecast and rapid response, enabling the implementation of an event-oriented sampling strategy.

Sacred Landscapes and Changing Sea Levels: New Interdisciplinary Data from the Early Neolithic to the Present in South-Eastern Sicily

Through the analysis of geomorphological processes coupled to archaeological time markers in one selected site – Ognina in south-eastern Sicily – this paper investigates ritual practices and sacred places associated with sea-level change and shoreline locations. The interdisciplinary approach adopted in this research also provides new data on relative sea-level change during the late Holocene, while at the same time bringing together diverse approaches and methods for the analysis of submerged landscapes. It also aims to act as a blueprint for future directions in this specific field.

Uplifted Late Holocene shorelines along the coasts of the Calabrian Arc: geodynamic and seismotectonic implications

Late Holocene (~6.5 ka) shorelines represented by tidal notches, beach deposits, wave-cut terraces and intertidal organic rims are raised from few decimetres up to 5.5 m above the present sea level in the southern part of the Calabrian Arc, southern Italy. At five localities (Capo Vaticano and Scilla in southern Calabria and Taormina, Schiso, Capo Milazzo in north-eastern Sicily), the uplifted paleo-shorelines form a distinct vertical sequence where the older shorelines rest invariably above the younger ones. Such arrangement documents the occurrence of abrupt uplift events that, within the limits imposed by existing age controls, we attribute to ancient earthquakes. A comprehensive appraisal of published studies has allowed to draw an inventory with a total of possibly sixteen earthquakes which, based on the amount of shoreline displacement (~0.5-2 m) and the length of coastal section involved in uplift, were likely to be of strong size. It appears that the amount of uplift decreased with time during the Late Holocene at all sites but Capo Vaticano, where it remained almost stationary. The co-seismic events appear grouped within four temporal clusters, during which uplift occurred at most of the five coastal sectors investigated here. These clusters spanned time intervals whose duration, although difficult to bracket with precision, is of few hundred years, and are separated by longer (~0.5-1.5 ka) periods of apparent tectonic quiescence. The sources of co-seismic uplifts are still undefined, and should be searched between normal faults in the stretched Calabrian upper crust, or lower crustal thrust faults related to the Ionian subduction.