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The integrated interpretation of different types of data, consisting of a detailed Digital Terrain Model, field structural and morphotectonic observations, high resolution seismic data, seismological and Synthetic Aperture Radar interferometry information (vertical and horizontal movements), associated with a review of the available literature, has allowed to analyze the shallow expression of the regional-scale Petilia-Sosti Shear Zone (PSSZ). It is one of the major NW-trending tectonic lineaments affecting the Calabrian Arc and is characterized by a present-day tectonic and gravity-driven deformation. This study investigated the portion of the PSSZ between the offshore Crotone Peninsula, located along the Ionian sea of Calabria, and the central part of the Sila Massif. A complex tectonic history is documented since middle Miocene onward for the PSSZ. It consists of an alternation of sinistral and dextral transpressional and transtensional tectonic phases correlated with the geodynamic events occurred during the SE migration of the Calabrian Arc. The shallow expression of the investigated part of the PSSZ consists of a roughly 14 km wide, ca. 80 km long NW-trending tectonic zone including synthetic NW- to NNW-trending faults and N-NE antithetic minor structures. The main identified NW-trending faults, which show a development between 30 and 50 km, are the Sila and Lakes faults in the Sila Massif, and the Marcedusa-Steccato, Fosso Umbro and Tacina faults located in the SW part of the Crotone Basin and in its offshore area. Currently, the fault segments of the Sila Massif exhibit a prevailing normal kinematics with a left-lateral component, whereas a more complex geological framework occurs in the south-western part of the onshore-offshore Crotone Basin. The latter is dominated by gravity-driven movements, associated with the SE migration of the Crotone Megalandslide and with the regional uplift of Calabria, whereas normal kinematics with a small left-lateral component of movement, locally replaced by reverse/transpressional tectonics, was observed along the southern coast in the late Pleistocene deposits of the Le Castella marine terrace. The seismological data highlight that some strong earthquakes occurred in 1638, 1744 and 1832, with magnitude Mw between 5.7 and 6.8, might be associated with the Lakes, Fosso Umbro and Tacina faults respectively. In this frame, the PSSZ is proposed as a new potential NW-oriented active composite seismogenic source for the central-northern Calabria.

In the context of the MaGIC (Marine Geohazards along the Italian Coasts) project we propose a geohazard map of the Calabrian coast between Capo Spartivento and Capo Rizzuto (Ionian Sea) based on the interpretation/elaboration of Multibeam and CHIRP data acquired in summer 2005 with the R/V OGS EXPLORA in framework of the MESC project ((Morphology and Evolution of the Submarine Canyons in the Ionian Margin of Calabria- University of Trieste, Italy).

The Ionian slopes of the Calabrian continental margin have been affected by mass movements of varying style, scale and age. Here we present examples of seabed and subsurface features identified from recently acquired multibeam morpho-bathymetric data and sub-bottom profiles, being interpreted in the framework of the MAGIC project. Four different types of mass wasting phenomena are recognized: mass transport complexes (MTCs) within intra-slope basins, isolated slide scars on slopes, possible features of gravity sliding above Messinian salt and headwall scarps in canyons. An improved understanding of past and present processes of mass failure on the Calabrian margin is strategic for assessments of the geohazards they may represent.

A new calcareous-dolomitic horizon of a platy-dolomite type (sensu BERNIER, 1994), containing the remains of a Cenomanian continental palaeoflora, is reported. The platy-dolomite crops out in the Mount Chianello carbonate ridge (sheet tav. I.G.M. 1:25.000, 198 IT S.W. - Castel San Lorenzo), dominating the village of Magliano Vetere (SA). This ridge is a deformed part of a Mesozoic-Cenozoic platform (campano-lucana platform in D'ARGENIO et alii, 1973; apenninic platform in MOSTARDINI & MERLINI, 1986). A 200 m thick interval of the sequence has been sampled in order to date this platy doloinite. On the basis of facies, it has been divided into four intervals which are, from bottom to top: a) 50 m stromatolitic dolomite and limestones below the platy dolomite, showing the sedimentological features of a restricted lagoonal environment in an inner carbonate platform. Among the microfossils, Sellialveolina viallii COLALONGO, Nezza-zata simplex OMARA, Pseudolituonella reicheli MARIE, Biplanata peneropliformis HAMAOUI & SAINT-MARc and Pseudorhapydionina dubia (DE CASTRO) are present. This fossil assemblage indicates in age ranging from the base of the Cenomanian up to the middle Cenomanian (DE CASTRO, 1991). b) 70 m thin-bedded dolomite and dolomitic limestones of which the typical platy dolomite facies constitutes 40 m in which sets of millimetre-scale laminae are frequently present and often contain terrestrial floral remains on the laminae surfaces. The fossi-liferous horizon is ascribed to the middle-upper Cenomanian by, the presence of Nezzazata simply OMARA, Biconcava bemori HAMAOUI & SAINT-MARC, Biplanata peneropliformis HAMAOUI & SAINT-MARC Chrysalidina gradata D'ORBIGNY, Pseudorhapydionuna dubia (DE CASTRO), Pseudorhapydionina laurinensis (DE CASTRO). The sedimentological features of the platy-dolomite and fossil flora content suggest deposition in a tidal flat under upper- intertidal-supratidal conditions and, in particular, in an algal-marsh environment often exposed to dessication and storms, located close to a coastal area with primeval Angiosperms and Conifers. The first palaeontolological studies on this continental flora, allow its to ascribe some fossils to Sapindopsis sp.. c) 42 m limestones and bioturbated dolomite which, marks a drastic change in the environmental and sedimentological conditions on the carbonate platform, with heavily bioturbated bioderrital material (namely fragments of Rudists), often in massive lavers, proving a swift transition to deeper open marine conditions. In particular, the first 18 metres of this interval have many traces of Thalassinoid bioturbation. The tracks and burrows give an unmistakable appearance to the rocks and make this an important marker horizon in the whole ridge of Mount Chianello-Mount Vesole. Because of the presence in thin section of Dicyclina sp., Cisalveolina fraasi (GLMBEL) and Pseudorhapydionida casertana (DE CASTRO), a late Cenomanian age is assigned to this interval. d) 43 m of limestones and dolomite. The sedimentological features indicate an open carbonate platform emironment often with coarse biodetrital elements and in the upper part, a tendency to the emersion. This interval has been assigned to the Turonian by the presence of Murgeina apula (LUPERTO-SINNI). Biconcava bentori HAMAOUI & SAINT MARC and small Moncharmontia apenninica (DE CASTRO). In conclusion, the above observations show that the sequence including the platy dolomite of Magliano Vetere, ranges in age from the Lower Cenomanian to the Turonian. The flora of the platy dolomite is Middle Cenomanian in age and reflects an upper intertidal-supratidal environment. The plant remains ascribed to the genus Sapindopsis constitute the first Italian finding of this type and fit well with a shallow marine environment close to a coast line. The studied sequence documents peritidal or paralic environments with a restricted water circulation in the Lower Cenomanian, with a strong tendency to stagnation in the Middle Cenomanian (platy dolomite). The restricted conditions change drastically in the Upper Cenomanian with its bioturbated rudist fragment-rich horizons. As other similar horizons in the Mesozoic carbonatic sequences of the Southern Apennine (BRAVI, 1995), the platy dolomite of Magliano Vetere seems to fit well, due to its age, with a marked eustatic sea level minimum in the Middle Cenomanian; tis minimum is recognizable in the 3degrees order eustatic curve of HAO el alli (1987). As a final considerations, it could be said that the studied sequence is relevant to two important currents of research: The analysed stratigraphic imerval, because of its quality and thickness, is particularly appropriate for studies of the enironmental and ecological changes in carbonate shallow water platforms during the global anoxic event at the Cenomanian-Turonian (C/T) boundary, at present the object of important research (ERBA et alii; 2001; FORSTER et alii, 2001: KOLONIC et alii, 2001, WALSWORTH-BELL et alii, 2001). In the succession studied the Cenomanian Turonian boundary is located between the intervals c and d (see fig. 3). This transition represents a short period during which, in the neritic realm, strong environmental change and an important evolutionary overturn are associated. In the hydrocarbon context, the main source rocks in the Italian sedimentary sequences are constituted by organic-rich intervals deposited in shallow carbonate platform environments or in deep water interplatform basinal settings (KATZ et alii, 2000). Although similar rocks are present in a number of different stratigraphic levels, only those in the Upper Triassic-Lower Triassic (accumulations of Malossa, Rospo and Gela), Middle Triassic (accumulation of Villafortuna) and Upper Cretaceous (Monte Alpi) are at present known to have generated oil. Detailed geochemical studies (KATZ et alii, 2000) indicate that there is a sharp contrast in the stable isotope composition of the organic matter contained in the different Italian carbonate source rocks. The Triassic and Toarcian organic matter is isotopically light (delta C-13(bitumen)

Il contesto geodinamico che caratterizza lo Ionio settentrionale è estremamente complesso caratterizzato dall'interazione di diversi elementi tettonici che da NO- a SE sono: il Prisma di accrezione dell'Arco Calabro s.s. e l'avampaese costituito dalla piattaforma Apula. L'analisi integrata di dati morfobatimetrici e profili sismici multicanale recentemente acquisiti dalla N/R OGS Explora in varie campagne condotte tra il 2003 e il 2010, ha fornito nuove informazioni riguardo i processi strutturali che hanno coinvolto il margine dal Mesozoico al Presente

The upper Messinian to lower Zanclean succession of the Crotone Basin, a forearc basin located along the Ionian side of the Calabrian Arc (southern Italy), consists of a turbidite-bearing succession (the Petilia Policastro Formation) overlying evaporites and abruptly passing upward into coarse-grained continental deposits (the Carvane Conglomerate), which are in turn overlain by distal shelf to slope mudstones (the Cavalieri Marl). The marked environmental changes from subaqueous to continental and vice versa documented by the studied succession are inferred to be the expression of basin-scale tectonics, leading to uplift and exposure, superposed on the Mediterranean-scale base-level rise that followed the acme of the Messinian Salinity Crisis. The upper part of the succession documents a transgressive trend probably initiated within the Carvane Conglomerate, and further testified by the presence of a ravinement surface marked by a transgressive lag at the base of the Zanclean Cavalieri Marl, pointing to a non-catastrophic deepening occurred near the end of the Messinian.

The contributions of eustasy and tectonics to the development of stratigraphic sequences are commonly hard to discern, and this has been a controversial topic that is still being debated. New data are therefore necessary to improve our understanding of the factors that govern sedimentary cyclicity. Data from the subsiding Venice and the uplifting Crotone areas in Italy allow the recognition of the different effects of Late Quaternary glacio-eustatic changes and regional tectonics on sequence architecture at different temporal scales. Shallow-marine small-scale sequences linked to short-term glacio-eustatic changes at the scale of the marine isotope substage cyclicity (10000 years) show features that developed irrespective of the local conditions of subsidence or uplift, such as a modest thickness, a similar organization of facies and thin transgressive deposits. In contrast, lower frequency composite sequences at the scale of 100000 years show strongly different architectures and stacking patterns depending on the regional tectonic context: downstepping in uplifting areas and aggradational in subsiding areas. The present results, therefore, highlight that only the architecture of small-scale sequences showing a periodicity of about 20 and 40 ka appears to be dominated by the glacio-eustatic variable, because of the very high rates of sea-level change characterizing the substage cyclicity, which overprints the regional tectonic signal.

The dating of young submarine volcanic eruptions, with their potential generation of tsunamigenic waves, is essential for a reliable hazard assessment. This is particularly relevant in highly populated coastal areas. The scarce knowledge of the underwater environment makes however, this reconstruction challenging. Our study is focused on the NW sector of the Sicilian Channel, where several small- and medium-size volcanic edifices are present. The only documented Surtseyan-type eruption occurred in A.D. 1831, forming the ephemeral Ferdinandea Island. Late Pleistocene to mid-Holocene eruptions have been up to now only hypothesized, and based solely on indirect data. Here we present the first radiocarbon dates of a coralligenous bioconstruction sampled at 34 m water depth from the summit of the Actea volcano, grown up progressively (up to nowadays) on a lapilli tuff deposit. Actea volcano is a recently discovered pyroclastic cone located at only four nautical miles off the SW coast of Sicily. The oldest age of the bioconstructions that started to encrustate the shallow water pyroclastics shortly after their emplacement (7,387 ± 175 cal years B.P.) represents a terminus ante quem, thus testifying a mid-Holocene submarine eruption in this sector of the Sicilian Channel. This method may be effectively used to bridge the gap between historical accounts and the geological record and thus may contribute to a better volcanic hazard assessment of submarine eruption and related phenomena such as tsunamis.

The structural setting of the northern Ionian Sea is the result of the collision between the Calabrian Accretionary Wedge (CAW) and the adjacent foreland, i.e. the Apulian Carbonate Platform. The CAW represents a sector of the Apennine accretionary system extending in the Ionian Sea, bounded to the west by the Malta Escarpment and to the east by the Apulia Escarpment. This work presents the results of the interpretation of new seismic and bathymetric data acquired on the north-eastern edge of the CAW, in the N-Ionian Sea. The data interpretation has identified four main structural domains from NE to SW: 1. The Apulian carbonate Platform consisting of foreland shelf and transitional Mesozoic-Cenozoic carbonate deposits; 2. A narrow foredeep basin, filled by a very thick Plio-Quaternary succession; 3. A deformed domain, at the front of the CAW, incorporating thrusted foredeep sequences and a carbonate block of the Apulian Platform (Transpressed Apulian Block, TAB); 4. A highly deformed pre-Pliocene accretionary wedge. A mid-Pliocene unconformity interpreted on both the CAW and Apulian Foreland suggests that a regional tectonic event occurred at that time, related to the evolution of Calabrian Arc, moving on the subducting oceanic Ionian slab before the collision. This event would correspond to a main tilting and faulting phase of the Apulian Foreland during the diachronous oblique collision with the CAW. The collision and the presence of a remnant of Ionian foreland at the southern front of the accretionary prism, caused a gradual transition to a transpressional tectonics which produced the uplift of the TAB. The TAB would be the south-east continuation of the Amendolara ridge transpressed structure, which forms the offshore extension of the Pollino range. This transpressed shear zone involving the Apulian Foreland developed above the transition between the Adriatic continental crust and the subducting Ionian oceanic crust.