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Interdisciplinary studies of the last years highlight that the Italian coasts are significantly subject to retreat and to inundation by sea ingression due to natural and anthropic causes. In this study, the effects of future relative sea level have been evaluated for the Volturno River Plain, one of the widest coastal plain in southern Italy. The plain is characterized by high economical and ecological value, for the presence of farm activities, tourist structures and wetland protected zones. The study area is potentially prone to coastal flooding due to its very low topography and because it is affected by a severe subsidence, which emphasize the local effect of sea level rise due to the ongoing climate changes. In accordance with the guidelines of the MEDFLOOD project, the areas prone to inundation in the years 2065 and 2100 have been evaluated by comparing the future topographical information and expected relative sea level scenarios. The local Vertical Ground Displacements have been derived by PS-InSAR processing data whilst the mean values of the scenarios RCP 2.6 and RCP 8.5 provided by the IPCC (2014) have been used as future sea level projections in 2065 and 2100. The PS-InSar data elaboration shows that the area affected by subsidence corresponds to 35% of the Volturno plain and that the annual rate of the phenomenon ranges between −1 and −25 mm/yr. The inundation analysis, based on the classification of the areas in four hazard classes, indicates that in 2065 the zones located below the sea level will increase approximately of 50% respect to the present conditions, while between 2065 and 2100 the increase can be at least of 60% (IPCC, RCP 8.5 scenarios). Considering the socio-economical and ecological exposure, evaluated following the EUROSION project guidelines, the coastal flooding risk maps have been produced. Almost 8.2 km 2 and 14.4 km 2 of the investigated area has to be considered subject to very high marine inundation risk in 2065 and 2100, respectively.

A multidisciplinary methodology, integrating stratigraphic, geomorphological and structural data, combined with GIS-aided analysis and PS-InSAR interferomettic data, was applied to characterize the relationships between ground deformations and the stratigraphic and the morphostructural setting of the Venafro intermontane basin. This basin is a morphostructural depression related to NW-SE and NE-SW oriented high angle normal faults bordering and crossing it. In particular, a well-known active fault crossing the plain is the Aquae Juliae Fault, whose recent activity is evidenced by archeoseismological data. The approach applied here reveals new evidence of possible faulting, acting during the Lower to Upper Pleistocene, which has driven the morphotectonic and the environmental evolution of the basin. In particular, the tectonic setting emerging from this study highlights the influence of the NW-SE oriented extensional phase during the late Lower Pleistocene- early Middle Pleistocene, in the generation of NE-SW trending, SE dipping, high-angle faults and NW-SE trending, high-angle transtensive faults. This phase has been followed by a NE-SW extensional one, responsible for the formation of NW-SE trending, both NW and SE dipping, high-angle normal faults, and the reactivation of the oldest NE-SW oriented structures. These NW-SE trending normal faults include the Aquae Juliae Fault and a new one, unknown until now, crossing the plain between the Venafro village and the Colle Cupone Mt. (hereinafter named the Venafro-Colle Cupone Fault, VCCF). This fault has controlled deposition of the youngest sedimentary units (late Middle Pleistocene to late Upper Pleistocene) suggesting its recent activity and it is well constrained by PSInSAR data, as testified by the increase of the subsidence rate in the hanging wall block. (C) 2017 Elsevier B.V. All rights reserved.

We investigated the northern slope of the Matese Mts. (Molise, Central Italy) with the aim of characterizing the N- to NE-dipping active normal fault system in the Bojano basin, a sector of primary importance from a seismic hazard perspective. We collected field data to define the geometry and segmentation pattern of two sub-systems (Patalecchia-Colle di Mezzo and Bojano–Campochiaro). New evidence of late Quaternary faulting was obtained by exploiting well log interpretations. Kinematic analysis revealed the interaction of pre-Quaternary inherited (mainly E-W-striking) and newly formed (NW-SE-striking) normal faults. Slip accommodation through linkage was clearly noted in the case of the Patalecchia-Colle di Mezzo sub-system. Detailed topographic profiles across the active fault segments provided post-LGM (15 ± 3 kyr) slip rates up to ∼2 mm/yr which agree with the high deformation rates based on different approaches in the literature. Finally, the instrumental seismicity analysis constrained the bottom of the seismogenic layer to depths of 13–14 km, and the gathered information allowed us to reconstruct the North Matese seismogenic source. Its 3D geometry and dimensions agree with both the dimension-magnitude relationships and macroseismic information available for the 1805 earthquake (Mw 6.6), the main historical earthquake to have struck the Bojano basin.

Two boreholes, both about 16 m-deep, have been drilled in the Garigliano Plain, a coastal-alluvial plain located at the boundary between southern Latium and northern Campania, Italy. The drill holes have been planned and carried out in the southern part of the plain, near to the bordering ridge of Mount Massico. The multidisciplinary analyses performed on sediment samples from both cores revealed the presence of several marine and continental sedimentation environments, transitional facies and volcanic rocks. All these data, together with the stratigraphic correlation between the two logs, allowed the reconstruction of the sedimentary and morphological evolution of the plain during the Late Quaternary. Further, such an evolutionary sequence has been used as a comparison scheme with regard to other coastal plains of the Tyrrhenian side of central and southern Italy to stress similar or different behaviours among them on a distance of about 400 km of coastal belt. Some remarkable differences have been actually enlighten, with particular reference to the MIS 5.5 and the Holocene. The occurrence in both cores of products of the Campanian Ignimbrite – a ~ 40 ka pyroclastic unit – and associated reworked deposits (about five metres-thick in both cases), has been here reported for the first time in the subsurface of the southern part of the Garigliano Plain. In addition, a tephra layer has been detected at −14.50 m of depth (i.e. 13.50 m a.s.l.) in the northernmost core. This layer has been 40Ar/39Ar dated at 124.5 ± 0.5 ka. In the upper part of the same drill core, deposits interpreted as lagoonal-swamp facies have been recognized. On the basis of 14C dating, we can attribute the starting stage of such a sedimentation to the effects induced by the Post-glacial sea-level rise at about 8000 yr BP. These chronological constraints permitted us to obtain from the paleoecological, palynological, and granulometric analyses of the sampled successions helpful and precise information about sea-level changes along that coastal belt.

This paper describes the results of a multidisciplinary study of four geoarchaeological sites on the Sorrento Peninsula coast (Italy) where the submerged ruins of Roman buildings have enabled the ancient position of both the sea level and the coastline to be reconstructed. The results highlight that the sea level in Roman times, deduced from the submersion measurement of archaeological markers, did not exceed 1.2 m ± 0.30 m, except for Seiano whose submerged remains and surrounding area were heavily damaged by extreme events following the 79 CE Vesuvius eruption. The comparison of these results with the eustatic sea-level curve in Roman times together with the submersion of the tectonically stable site on the Tyrrhenian coast of Italy (Torre Astura, with a well-preserved Roman fishpond) demonstrate that the Sorrento Peninsula has been tectonically stable over the last two millennia. This behaviour started many thousands of years ago, not later than the last interglacial, while the nearby plain of Pompeii and probably the bottom of the adjacent Gulf of Naples have been subsiding at rates of 1 or more mm per year. In the same time span, two of the investigated coastal sectors (Capo di Sorrento and Punta Campanella) have not suffered any significant changes because their sea cliffs are cut in hard limestone. The tufa sea cliff of the Sorrento plain on the other hand, has been retreating by several metres. On the Marina di Equa (Seiano) alluvial coastal plain, which suffered the effects of the 79 CE eruption, the debris and hyperconcentrated flow produced a progradation of > 200 m, which has been totally dismantled over three centuries.

Many coastlines around the world are subsiding, often due to tectonic causes. In tectonically active areas, the exploitation of natural resources has caused acceleration of subsidence rates. In these cases, it is difficult to separate the many different components of the subsidence process. We try to fill this gap, using both remote sensing data and geological evidence, in an area located in southern Italy (Sele River plain) and characterized by the presence of both human activities and natural processes. The coastal sector of the Sele plain shows a complex subsidence pattern, as testified by Persistent Scatterer Interferometry (PS InSAR) data related to a period of about two decades (1992–2010), that we put in correlation with stratigraphical data from both outcrops and boreholes (ca. 250). The Quaternary infill of the coastal sectors of the plain is not laterally isotropic and homogeneous because of the presence of layers of clastic sediments with different degrees of compaction. Dunal and beach sands, back-ridge (lagoonal and palustrine) silty clays, palaeosols and thick peaty layers are the main facies of this sedimentary prism. The back-ridge depressions hosted palustrine and marshy environments and were artificially drained in the last centuries. The main output of the PS- InSAR analysis is a map of vertical ground deformation (VGD), which has been a useful tool to understand the causes of the subsidence process if combined with geological data from field and boreholes. In fact, the overlay of the SAR interferometry VGD map with the geomorphological and stratigraphical features shows that the subsidence is higher in the northern sector of the plain, where the Quaternary alluvial-coastal deposits are thicker because of the structural asymmetry of the graben. The maximum subsidence rate, however, can be observed in the central part of the plain, in correspondence of the Sele, Tusciano and Picentino river mouths and in the coastal belt. This could be related to the thickness of loose sediments (>20 m) and to the presence of still compacting clay-rich sediments. In the southernmost sector the rates are the lowest recorded in the plain due to the minor thickness of Holocene deposits and to the presence of very thick sedimentary bodies of travertine. The understanding of subsidence patterns may represent a basic tool for future studies about the assessment of the coastal inundation hazard and related risk mitigation in the Sele River plain. Such a tool may reinforce the methodological approach to risk assessment in similar morphological settings.

This paper illustrates an index-based coastal risk assessment that was performed on a micro-tidal alluvial plain taking into account the relative sea level rise (RSLR) for the evaluation of coastal vulnerability and exposure. This process took into account both the inundation of inshore land and the beach retreat due to storm surge, calculated on the basis of geomorphological data (bathymetry, sedimentology and beach width) and wave climate. The evaluation process was conceived with reference to a low and high hazard, associated with a wave storm with 1 year and 50 years return period. For the latter case, the response to RSLR was calculated taking into account both isostatic response and ice cap melting due to global warming, while the vertical land movement was assessed taking into account the different its rates in the northern and southern coastal area. The exposure and the damage of the coastal assets were evaluated with a simplified conceptual framework, which uses land cover data and a statistical population dataset. The risk assessment procedure was applied to Sele coastal plain, which involves numerous properties and important infrastructures, and is strongly susceptible to marine inundations. A sensitivity analysis of the vulnerability and the risk relative to different hazards and to RSLR was performed. Moreover, the final risk assessment classification was validated with a conceptual framework based on the observed damage ranking related to the tested coastal area. The obtained results showed that the northern high density urban areas were characterized by the highest risk, followed by some central areas with strong localized erosive focus. On the contrary, the southern zones, with wider beaches and almost intact dunes, were characterized by the lowest risk level. The results of this study were used for the development of a coastal protection project which, in fact, provided a different scheme for the coastline northwards and southwards of the Sele river mouth, according to the different risk ranking established.

An integrated geomorphological, geological-structural and stratigraphic approach was applied to the Sessano intra-montane basin (Molise, Central-Southern Apennines) to understand the Quaternary environmental and sedimentary evolution of the basin and the surrounding areas. The morpho-evolutionary and sedimentary changes were mainly controlled by tectonics and strongly influenced by the huge amount of volcaniclastic input from the Roccamonfina volcano (located ca. 50km to the south-west) as well as by climatic changes. Chronological constraints, supported by Ar/Ar ages of tephra layers, archaeo-tephro-stratigraphy and pollen analysis, permit identification of the main phases of the geological-geomorphologic evolution of the Sessano basin from the Middle Pleistocene onwards. The sedimentation within the basin was controlled by NE-SW extensional tectonics and occurred from the end of Oxygen Isotope Stage (OIS) 15 to the beginning of OIS 11 allowing the deposition of ca. 85m of fluvial to lacustrine sediments, mainly made up of reworked volcaniclastic material. The first phase of sedimentation was lacustrine, while an important sedimentary change from lacustrine to fluvial-marshy environment occurred during OIS 14. After this phase, the variable input of volcaniclastic material from the Roccamonfina volcano together with climatic influences caused repeated changes from palustrine to fluvial sedimentation, and the formation of various palaeosols present mainly in the upper portion of the infill. Towards the end of OIS 11, NNW-SSE extensional tectonics caused the tilting of the fill succession and the drying up of the basin. The fill succession was then affected by fluvial erosion and denudation that generated an erosion surface nowadays hanging at 700-720m asl. This surface can be related to the limbs of a palaeo-surface at about 600m asl present in the adjacent Carpino-Le Piane intra-montane basin and referred to a fourth order, Tyrrhenian-ward oriented palaeo-landscape. This palaeo-landscape can be dated to ca. 350-300ky and, therefore, represents an important morpho-chronological stage. It provides a robust maximum and minimum age framework for reconstructing the geological and geomorphological evolution of the study area and, in general, of the Molise Apennines including the Boiano, Carpino-Le Piane and Sessano intra-montane basins. In particular, the morpho-chronological data from the Sessano basin allow us to date more precisely the main tectonic phases that occurred during the Middle Pleistocene in this sector of the Apennine chain. Finally, the multi-proxy data derived from the Sessano basin can be compared and integrated with those referring to other proximal intra-montane basins in order to improve our knowledge on the relationships between tectonics, volcanism and climate and the stratigraphic-sedimentary features, geomorphologic evolution and palaeoenvironmental changes that characterized the Central-Southern Apennines during Middle Pleistocene. © 2010 Elsevier B.V.

The long-term denudation rate has been evaluated within an actively deforming area (the Southern Apennines Chain), using both geomorphological and GIS-aided analysis of a 2738 km 2 representative sample area. The rock volume contained between a reconstructed palaeotopography and the present topography of the study area has been calculated. Palaeotopography has been reconstructed on the basis of the relics of an irregular surface, whose tentative age is 0.8–0.6 Ma, and also includes remnants of a more ancient, more suspended and badly preserved palaeosurface. To represent the modern topography, a certified DTM of Italy, with grid 230×230 m 2 , was adopted. The calculated rock volume eroded since the beginning of the dissection of the palaeosurface is 478 km 3 , which implies an average erosional downwearing of 175 m. However, downwearing is not uniformly distributed over the area, as it is concentrated along valleys. In particular, the same major valley trunks that already existed at the beginning of the Middle Pleistocene, show downcutting amounting to 400 m and more, while the amount of erosion on the divide areas is of the order of a few tens of metres. The resulting mean denudation rate falls between 0.22 and 0.30 mm/a.