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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.

Coastal areas are very dynamic environments where natural and man-induced modifications often interact. This is the case of the Graeco-Roman town of Elea-Velia, along the Cilento coast of southern Italy. The town was founded in the 6th century BCE on a hilly promontory bounded by two profound gulfs and assumed a prominent role in maritime commercial routes in the Graeco-Roman period. It declined in the Late Antiquity and was abandoned in the Middle Ages also due to serious landscape changes. In this study, the integration of geomorphology, borehole stratigraphy and analysis of archaeo-stratigraphical trenches was used to detail the relationship between geological and archaeological evidence. The huge amount of collected data allowed providing chronological constraints to the landscape modification occurred before and after the town foundation. The main environmental changes consisted in enhanced coastal progradation and alluvial fan deposition that mainly affected the lower quarters of the town. The results of this study suggest that alluvial flooding was one of the main causes of the Elea-Velia decline and subsequent abandonment. The increasing disruption of slope stability was driven by the neglect in the management of the hillslopes behind the town during periods of social-economic crisis, but a concomitant climate forcing cannot be excluded. To the final abandonment also contributed the declining of harbour activities and the consequent decreased relevance of Elea-Velia as a maritime centre.

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.

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.

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.