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This paper investigates how hydrological drought affected suspended sediment yield (SSY) in the Mediterranean Ofanto River basin, southern Italy, and in its five sub-basins from 1951 to 1989. The Standardized Precipitation Evaporation Index over a scale of 12 months (SPEI12) has been used to compute the hydrological drought in the investigated span of time. SPEI12, mean and maximum monthly discharge (Qmean and Qmax), monthly rainfall erosivity, monthly simple daily intensity index and monthly SSY were used to assess the relationships between dry/wet cycles, streamflow and SSY through the Pearson correlation matrix. Qmean and Qmax are significantly correlated with SSY, while SPEI12 and rainfall intensity do not show good correlation with SSY. Furthermore, from the overall analyses it emerges that sediment yield estimations were higher mainly during the wet period following a period of drought or during a drought period. [ABSTRACT FROM AUTHOR]

The analysis of 4 year In-SAR Interferometry images and a detailed geomorphological survey have been carried out to detect a large Deep-Seated Gravitational Slopes (DSGSD) affecting the urban area of the Episcopia village, in Southern Italy. The DSGSD largely develops within phyllites of the Liguride Units and, in the upper slope, within Pleistocene sand and conglomerate deposits of the Sant'Arcangelo Basin. Field survey has shown trenches at the top and an evident bulge at the base of the DSGSD, corresponding to the Talweg of the Sinni River. Geological and geomorphological field surveys allowed us to hypothesize a listric geometry of the DSGSD subsurface plane reaching about 700 m of depth. Furthermore, the multi-temporal In-SAR Interferometry analysis collected from November 2014 to May 2017 revealed that a ground deformation of ±30 mm was occurred, and the process is still active in the whole area. [ABSTRACT FROM AUTHOR]

The Brindisi di Montagna Scalo Landslide in Southern Italy is an active complex mass movement, which affects the left slope of the Basento River. In the last few decades, this landslide has been continuously monitored, as it directly threatened some of the most important communication routes in the Basilicata Region. Nevertheless, little progresses have been made to prevent further landslide advancement, and continuous maintenance is required. With the aims of better understanding, the main factors controlling the evolution of this landslide, and suggesting the most appropriate countermeasures, a multidisciplinary study, based on the integration of direct and indirect techniques, was carried out. Direct techniques included multi-temporal geomorphological analysis of the slope, alongside geological and structural field observations. Indirect techniques consisted of electrical resistivity tomography acquisition. The combined analyses of the geological and geophysical data showed that Quaternary tectonic processes played a fundamental role as a predisposing factor, whereas seasonal rainfall, and the perpetual undercutting by erosional processes caused by the Basento River at the toe of the landslide are the main triggering mechanisms. The Brindisi di Montagna Scalo Landslide represents an outstanding case-study, concerning the interaction between a flow-like complex landslide and essential linear infrastructure, such as motorways and railways. [ABSTRACT FROM AUTHOR]

This paper presents the results of geomorphological investigations carried out in Basilicata region (Southern Italy) in the sector of the youngest foredeep (Bradano trough) relative to most of the communal territory of Pisticci. The importance of the chosen area mostly lies in the presence of diffuse running-water landforms and landslides affecting urban areas. The geomorphological processes are linked with Quaternary tectonic uplift affecting the Apennine front-Bradanic foredeep sectors. A series of field surveys, supported by aerial photo interpretation, have led to the production of a geomorphological map at 1:35,000 scale which outlines the main processes and related landforms recognised in the study area. The latter are the result of the complex interplay of structural, gravitational and fluvial processes. Particular attention has been devoted to the recognition, identification and mapping of landslides which affect the slope, locally giving rise to hazardous conditions. [ABSTRACT FROM AUTHOR]

The Southern Apennines consist of a Cenozoic to Quaternary fold and thrust belt characterized by a complex structural architecture. In the axial portion of the chain, corresponding to the Agri Valley, folds and faults with multiple styles formed during the progressive emplacement of various tectonic units, derived from different paleodomains. In the available geological maps, the geometry of these tectonic structures is often hindered by scarce cartographic detail due to the use of basic stratigraphic subdivisions. Therefore, at the aim to better define these structures and contextually update the outcropping stratigraphic units, we realized a detailed geological map, which take into consideration not only the formation as basic stratigraphic units, but also finer subdivisions such as members or beds. Using this approach, we improved the stratigraphy of the area, we recognized new geological units and, eventually, we reconstructed the structural setting, and the tectonic evolution of the Agri Valley in detail. [ABSTRACT FROM AUTHOR]

Abstract: Piping (tunnelling) appears to be one of the more significant methods of erosion in the badlands in the Plio-Pleistocene marine-sourced clays of the Basilicata area in Southern Italy. A detailed field investigation of the pedological, textural, mineralogical and geochemical properties of the clay-rich terrains widely outcropping in two selected badland field sites (the Fossa Bradanica area and the Bacino di Sant''Arcangelo) was undertaken to further elucidate process variability across the complex site. Paralleling findings from other piped badlands, certain physico-chemical properties of the clays were found to influence the different erosional processes in fundamental ways. The very dispersive nature of the materials enhances pipe enlargement so that subsurface flow rapidly becomes the dominant process, causing pipe enlargement by a process of positive feedback. The paper speculates on the progressive role of surface and subsurface processes in the genesis of all evolutional badland forms (calanchi, calanchi mammellonari and biancane). In an early stage, the calanchi mammellonari are produced, as slope mounds become increasingly separated by a dense network of small inclined pipes in the intermediate part of the slopes, a site which is presumed to favour elevated subsurface flow. When the overburden collapses, many cones are isolated in these portions of the slope. A second stage follows in which overland flow dominates, with the water canalizing into small gullies generated by the collapsed crust. At the base of many slopes, this same mechanism produces biancane as residual cones. Because of the structural weakness of piped materials, mass movements cannot be ruled out. In a few locations, landsliding may be involved, especially in the formation of calanchi mammellonari. In this case the intersection of the vertical pipes with the impermeable substratum focuses subsurface flow, and collapse of the surface along this failure plane. Subsequent remodelling occurs by surface processes, since the ‘catchment volume’ for large pipes no longer exists. This interpretation differs from that of others who have argued that in other locations the biancane formation is linked to the development of large vertical pipes along tectonic joints. [Copyright &y& Elsevier]