GNGTS 2013 - Atti del 32° Convegno Nazionale

and techniques of seismic and sequence stratigraphy, as described in the guidelines for the redaction of marine geologic cartography (Catalano et al. , 1996; Fabbri et al. , 2002). Laterally coeval depositional systems, representing portions of system tracts of Late Quaternary depositional sequence have been recognized and their possible mapping has been taken into account for the cartographic representation. The seismic units have been later interpreted in terms of depositional sequences and corresponding unconformities have been interpreted as Type 1 or Type 2 sequence boundaries and/or as local unconformities, mainly at the top of relic volcanic edifices or at the top of volcanic seismic units (D’Argenio et al. , 2004; Aiello et al. , 2005; Ruggieri et al. , 2007). The marine geological maps, realized based on the above mentioned criteria shows the distribution of several lithostratigraphic units cropping out at the sea bottom and of the main morphological lineaments, based on the CARG guidelines for the realization of marine cartography (Catalano et al. , 1996; Fabbri et al. , 2002). The main stratigraphic units individuated through the analysis of sea bottom sediments belong to the Late Quaternary Depositional Sequence; in this sequence, it is possible to recognize the space and time evolution and the lateral and vertical migration of marine coastal, continental shelf and slope depositional environments in the Late Pleistocene-Holocene glacio- eustatic cycle. The stratigraphic succession studied by geological survey has recorded the variations of the accommodation space of the Late Quaternary deposits during the last 4th order glacio-eustatic cycle, ranging between 128 ky B.P. (Tyrrhenian stage) and the present (isotopic stage 5e). One aim of the cartography has been the cartographic representation of the lithofacies associations, whose grouping form the depositional elements (which are portions of system tracts), in relation to the morpho-structural lineaments recognized through the geological interpretation of the geophysical data and the dynamics of depositional environments. In this way, we tried to realize an integration between classical stratigraphic approach, sequence stratigraphic approach and characterization of actual and recent depositional elements. The volcanic activity, which has mainly controlled the stratigraphic architecture of the Naples Bay prevented a classical stratigraphic approach in the marine geological mapping, which has been realized taking into account both the associations of depositional systems and the interstratified volcanic bodies (volcanites and volcanoclastites). Moreover, this stratigraphic approach allowed obtaining information comparable with other sectors of the Italian continental margins. The last Quaternary sea level rise, having an excursion of about 120 m and a maximum rate in the order of 10 m/1000 years has left a stratigraphic signature on the morphologic and stratigraphic framework of most continental margins of the world (Chappell and Shackleton, 1986). The deposits associated to this process are strongly different in the various areas, as a function of different sediment supply, morphological framework and oceanographic regimes; to map these deposits allows to correlate the unconformities (erosional and non-depositional) and to compare the facies, the internal geometries and the thickness of the deposits recording the sea level rise in a differential way on the several margins. The key to the geological maps. The key to the geological map n. 465 “Procida” includes the description of the geologic and morphologic elements. The areal geological elements are represented by two superimposed levels: the textural classes distinguished following the classification of Folk (1954), graphically distinguished with halftone screens; the depositional elements, distinguished with the full colour. The superimposition of the environmental information on the textural one allows for a more complete reading of the cartography, furnishing at the same time geological and environmental information. The morphological elements, both areal and linear represent another level of graphic superimposition to the geological information. 176 GNGTS 2013 S essione 3.3