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The Boiano Basin is one of the largest Quaternary intermontane basins of the central-southern Apennines within one of the most tectonically active areas of the Mediterranean region. In order to reconstruct its entire Quaternary stratigraphic, tec- tonic, and palaeoenvironment evolution, lithofacies and palaeomagnetic analyses have been performed on a 900 m-deep borehole (CP1) drilled in the southwestern sector of the basin. The Quaternary succession consists of an alternating of alluvial fan and fluvial-marshy deposits for a total thickness of 240 m, unconformably laying on Lower Miocene deposits of the Sannio Unit, thrusted on upper Miocene deposits of the Molise Flysch. In addition, the stratigraphic study and facies distribution of 29 intermediate and shallow wells drilled in the basin, allowing us to define the thick- ness and lithofacies variations of the Quaternary sedimentary units inside the entire Boiano Basin in the sector of Campochiaro alluvial fan. Our results demonstrate that the Boiano Basin infilling started during the late Early Pleistocene (c. 1.1 Ma) and developed with variation in lithofacies distribution and thickness. The first deposi- tional unit (Early Pleistocene-early Middle Pleistocene in age) was palustrine and fluvial-marshy, the second (Middle Pleistocene in age) was characterized by the occurrence of the first cycle of alluvial fan deposition, the third (late Middle Pleisto- cene in age) was newly palustrine and fluvial marshy and, finally, the fourth recorded two cycles of alluvial fan deposition (late Middle Pleistocene and Late Pleistocene in age, respectively), interspersed by short periods of palustrinity, tephra layers deposi- tion, and palaeosols development. The study allows the hypothesizing that the Qua- ternary infilling was accommodated within a graben (or semigraben) structure, affected mainly by extensional fault systems localized in the inner part of the basin and secondly by fault systems bounding the basin.

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.

An integrated morpho-stratigraphic approach has been used to reconstruct the Quaternary history of the Boiano basin, the largest tectonic depression of the Molise Apennine (Italy). Lacustrine, marshy and fluvial environments alternate all along the investigated infilling succession as a response to tectonic subsidence, volcaniclastic inputs and climate changes, from ca. 500 ka. Two tephra layers 40Ar/39Ar have been dated and referred to the Middle Pleistocene explosive activity of the Roccamonfina volcano, while a younger tephra layer has been related to the Campi Flegrei Neapolitan Yellow Tuff (ca. 15 ka). Pollen analysis has highlighted the vegetation changes related to the 100 ka glacial-interglacial cyclicity, between MIS 13 and 2. From 500 to 350 ka, a strong subsidence led to lacustrine deposition, while between 350 and 250 ka, a decrease in subsidence rates caused the transition to fluvial-marshy conditions and, at a later stage, to floodplain environments. The analysis of palaeosurfaces allowed the geomorphological evolution of the basin to be reconstructed since the Middle Pleistocene and the morpho-sedimentary events to be related to the SW-NE extensional tectonics affecting this sector of the central-southern Apennine. This tectonic behavior is also testified by the differential subsidence rates recorded within the basin through the analysis of two deep cores drilled in the center of the Boiano town.

In order to assess the effects of possible future sea-level rise in the Sele plain, the lowlands prone to inundation and the rate of coastal erosion in the years 2050 and 2100 have been discussed and some conclusions are here proposed. The sea level at these two dates was calculated as the combination of three components: response of Italian coastal zones to the past deglaciation, variations in ocean volume due to the global warming and vertical land movements. The morpho-stratigraphical data, chronologically supported by C-14 and by archeo-tephro-stratigraphical dating, have allowed the identification of paleo-sea levels of the upper Pleistocene and Holocene (Amato et al. 2011). Such paleo-sea levels compared with those of the tectonically stable areas (Lambeck et al. 2011), permitted the detection of the different vertical land movements in the study area. In particular, in the SE sector of the coastal plain, the Holocene paleo-sea levels are slightly higher (ca. 1-2 m). These values could be considered due to a gentle uplift of the area during Holocene times (0.22 mm/year). In the central sector of the plain, near the Sele river mouth and in the NW sector, between the Sele and Tusciano river mouths, the altitude of the Late Quaternary coastal and lagoonal deposits are slightly lower (ca. 2-3 m). These values could be related to a gentle subsidence of the area during the Holocene (0.4 mm/year). The sea level rise of 5.9 mm/year (IPCC 2007) and 14 mm/year (Rahmstorf 2007) was considered to represent the maximum trends in the ocean volume variation at global scale. The third component, the glacio-hydro-isostasy, was represented by the value of 0.44 mm/year identified by Lambeck et al. (2011) at the Sele plain. The sum of these three components allowed to identify three sea-level scenarios slightly different for the northern and the southern sector of Sele plain, with values ranging from 357 to 1,526 mm and from 307 to 1,424 mm, respectively. For each scenario a simple approach was used, mainly based on the topographic elevation analysis of study area, applied to identify the extension of possible areas of inundation. It corresponds to a minimum value of about 0.42 km(2) for the 2050 AD and a maximum value of 7.6 km(2) for the 2100. Furthermore, according to the methodology proposed by Davidson-Arnott (2005), also the beach erosion was evaluated. The computations showed a potential mean landward retreat of the shoreline ranging from 19 to 93 m.

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.

A 1:28,000 scale geomorphological map of the central sector of the Matese Mountains (Southern Italy) is presented in this paper. Geomorphological investigation by means of remote sensing, cartographic analysis and field surveys allowed the identification of the main geomorphic processes and to map the related landforms which are both of monogenetic and polygenetic origin. Most of them are erosional landforms generated by the action of periglacial, glacial and karst processes which often occur under the control of the geological structure. Glacial relics and polygenetic landforms of glaciokarst and fluviokarst origin provide good evidence of the strong influence of variable climatic conditions on landform genesis during the Quaternary. They also highlight the influence of extensive tectonics during the Quaternary which caused progressive uplift, fragmentation and disarticulation of the developing mountainous landscape and its consequent polycyclic evolution. The map illustrates the geomorphologic peculiarities of the Mediterranean mountain landscape that typically characterizes the Apennine chain, and contributes to the understanding of its tectonic evolution and the influence of climate and climatic changes on landscape evolution. It further provides a basic map for land planning policy including the exploitation of the geological heritage and the development of sustainable mountain tourism and geo-tourism. © 2013 Copyright Francesca Filocamo.

New morphostratigraphic and chronological constraints for the Quaternary paleosurfaces of the Molise Apennine (southern Italy)The Molise Apennines feature numerous relicts of paleosurfaces, mostly of erosional origin, which represent the remnants of gently-rolling ancient landscapes now hanging at different altitudes above the local base-levels of erosion. Their genesis can be related to prolonged periods of relative tectonic stability alternating with periods of uplift, or to the interplay between steady tectonic uplift and climatic fluctuations. Four orders of paleosurfaces were recognized: I (> 1,100 m a.s.l.), II (900-1,000 m a.s.l.), III (750-850 m a.s.l.), IV (600-720 m a.s.l.). The most ancient orders (I and II) are cut into the bedrock and are located at the top of the Matese and Montagnola di Frosolone massifs. The youngest paleosurfaces (III—IV), partially cut into Quaternary deposits, are found along the valley flanks of the main river systems and within the Boiano, Carpino, Isernia and Sessano intramontane basins. The present study deals with the dating of the Sessano Basin Paleosurface (SBP) which is related to the IV order and is cut into the basin infill. The40Ar/39Ar age of a tephra layer (437 ± 1.9 ka), intercalated at the top of the succession, supported by archaeo-stratigraphic, palynological and paleopedological data, allowed the SBP surface to be constrained to 350-300 ka. The SBP chronological position represents an important morphostratigraphic marker: it is the firstante quemandpost quemdate that allows the chronological position of the other orders of paleosurfaces to be better constrained.