Note Illustrative alla Carta Geologica d'Italia alla scala 1:50000, foglio 486 Foce del Sele

The present sheet of the 1:50,000 Carta Geologica d'Italia falls entirely in the so called Piana del Sele (i.e. Sele River Plain). This alluvial-coastal plain lyes on Quaternary sediments that were accumulated inside a coastal half-graben, which continues in the off-shore with the deep Salerno Gulf. As shown in Fig. 1, this tectonic depression cuts the -orogenically speaking- inner side of the Southern Apennine chain, being interpreted as an effect of the opening and eastward migration of the Tyrrhenian Sea back-arc basin. The present day bathimetry of the Salerno Gulf is shown in Fig. 2, while Fig. 3 shows the thickness of the basin fill by isopachs in milliseconds t.w.t.. The main tectonic features of the basin are described in Fig. 5 and 6, according to Sacchi et alii (1994) for the off-shore and according to the present authors for the faults running either near coast or on land. The logs of Mina 1 and Sele 1 wells (Fig. 5 and 6) account for the deep stratigraphy of the basin fill, but there are still doubts about the age of its lowest terms and, consequently, the beginning of collapse. However, most authors agree that the present day morphostructural setting is due to Quaternary extensional tectonics, controlled by a NW-SE oriented ?3. On land, the first phases of the collapse (and generation of strong relief) is evidenced by the deposition of the so called Conglomerati di Eboli (i.e., the Eboli Supersynthem; CE). This thick and widespread clastic unit of the Lower Pleistocene is deeply buried in this Sheet (Fig 7) but it is largely exposed in the Sheets 467 and 468. It is mostly composed of fan-glomerates whose clasts came from the dissection of the Mt. Picentini massif, where a thick succession of tectonized 134 Mesozoic limestones and dolostones crops out. Around the beginning of Middle Pleistocene, the geomorphology of the Plain was re-shaped by normal and transtensional (transfer) faults (Fig. 8). Part of the area carrying the Lower Pleistocene fanglomerates was uplifted, while another large part of the Plain continued to subside and started accomodating the Battipaglia-Persano supersynthem (BP). This unit, which is up to some hundreds meters thick, covers large part of the present Sheet and associates with a wide depositional terrace that rests at 16-18 m a.s.l. closer to the modern coast and rises up to 100 m a.s.l. and more near the mountain front (where alluvial fans increase locally its elevation; Fig. 9). Even though never sampled and studied in detail, the lower part of the BP supersynthem is lithostratigraphically described in the logs of numerous drillings for water research. There it appears composed of decametrica alternations of coarse grained intervals of probable fluvial origin, intervals dominated by grey to blue clays (sometimes with peat and fossils) of probable lagoonal origin and intervals of matrix free sands of probable beach and coastal dune environments. Thickness and facies of the supersynthem's lower part prove that its deposition was accompanied by subsidence and, maybe, NW-ward tilting (see Fig. 8). The younger part of the supersynthem BP was investigated in detail with a number of new drillings (see Appendice 1), palaeo-ecological analyses and correlations with the logs of many pre-existing perforations. As shown in Fig. 14, it is composed of coarse and fine grained alluvial deposits close to the hills of Battipaglia (area of the ancient fan of the Tusciano River; see Fig. 9), while the coeval, more distal part of it is composed of a number of coastal parasequences that give evidence of several regressions and trasgressions. Based on pollen data and relations with the Gromola Synthem (see below), those fluctuations are tentatively framed between the OIS 9 and 5.5. As proved by the elevation of