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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]

Landslides represent a major geomorphological feature influencing the evolution of the southern Apennine slopes with earth flows being one of the most representative types of landslide. The development of earth flows in the southern Apennines is facilitated by the widespread occurrence of clayey lithologies. Earth flows can either produce marked scars along the slopes, when their activity is high, or give rise to bumpy areas that are frequently covered by vegetation, when their activity is low. In this latter case, although the risk is significantly reduced, the earth flow can still represent a problem for buildings and infrastructure. The Picerno earth flow in the Basilicata region is an example of a low-activity earth flow. This NW-SE–oriented landslide extends for a length of ~ 5.5 km, has an average width of ~ 680 m, and affects the village of Picerno. Our investigations mainly focused on the terminal portion of the landslide and revealed that some significant linear infrastructures (e.g., the Potenza–Naples railway) and important provincial and municipal roads are affected by the earth flow. In order to better define the amount of displacement characterizing the Picerno earth flow and gain insights into the lateral extension and the depth of the main detachment surface, we undertook a detailed geological and geomorphological survey. Interferometry synthetic aperture radar data provided by the processing of SAR images, with the aim of highlighting the regions of the landslide that are currently active, together with electrical resistivity tomography data which have been utilized to define the geometry of the landslide body. Our results provide useful suggestions for planning appropriate actions aimed at stabilizing the landslide body. [ABSTRACT FROM AUTHOR]

• Rapid geomorphological evolution occurred in the erodible lithology and semiarid climate of southern Italy. • A deposition phase during the Little Ice Age (LIA) was the last global cold climatic phase. • Badland incision occurred during Mediaeval Warm Period and continued in stably alternating phases until 1700 CE. • Valley aggradation ended early in 1850 as a phase of historic arroyo cutting began. • Geomorphological evolution around Basilicata during the LIA was very rapid and controlled by extreme surface process sensitivity to climate change. There is a general consensus that the increased frequency of extreme climatic events will quickly change the morphology of the landscapes in the Mediterranean area. Knowing and understanding the expected changes becomes crucial for defining future adaptive strategies. This paper deals with the very rapid geomorphological evolution in an emblematic Mediterranean area, the Basilicata region of southern Italy, during the last 300 years. The results show that the landscape evolution was mainly controlled by the extreme sensitivity of surface processes to climate change. Landslides, a new cycle of the formation of badland landforms such as calanchi and biancane, and an aggradation/incision phase in the main river valleys have completely reshaped the landscape of the Bradanic Trough, whereas fresh eroded material was moved to the coast. New data on valley-fill alluvium in the Basento River and one of its main left tributaries, the Vella stream, show ages ranging from 1700 to 1850. This deposition phase coincides with the Little Ice Age, an epoch of global climate variability. Previous literature showed that the alluvium of this age consists of a mappable stratigraphic unit outcropping in all the large alluvial valleys of the Basilicata and Mediterranean regions. Palaeoclimate and high-resolution palaeoflood data indicate that valley-fill alluviation occurred during a long humid period. Valley aggradation ended in approximately 1850 with the beginning of a new phase of historic arroyo cutting, mainly due to high magnitude-low frequency rainy events within prolonged drought periods. The stream incision drew the terminal dissection of the clayey slopes into biancana rounded morphologies. These data seem to be confirmed by the comparable heights of about 3 m, both of the biancane and of the fluvial terraces. [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]

This paper presents the results of geomorphological investigations carried out in Basilicata region (southern Italy) from the most external thrust front of the Apennines, where the town of Craco is located, to the adjacent sector of the Apennines foredeep (Fossa Bradanica; Pisticci area). The importance of the chosen area mostly resided in the presence of really diffuse running-waters and gravity-induced landforms which strictly affect urban areas. The geomorphological processes are linked with the Quaternary tectonic uplift affecting the Apennine front-Bradanic foredeep sectors. Series of field surveys, supported by aerial photo-interpretation, have led to the production of a geomorphological map at 1:16,000 scale which outlines the main processes and related landforms recognized in the study area. The latter are the result of the complex interplay of structural, gravitational and fluvial processes. Particular attention was devoted to the recognition, identification and mapping of landslides which affect the slope of the main villages (Craco and Pisticci), locally giving rise to hazardous conditions. [ABSTRACT FROM AUTHOR]

Two volcaniclastic successions intercalated in Pliocene basinal clays from the Southern Apennines have been analysed to determine their provenance and their relationship with the geodynamic evolution of the Western Mediterranean. The studied deposits are exclusively made up of ashy pyroclasts, dominated by fresh acidic to intermediate glass, mostly in the form of shards, pumice fragments and groundmass fragments with vitrophyric texture. Crystals include P1, Opx, Cpx, Hbl and rare Bt. Sedimentological features suggest that the volcanic material accumulated near the basin margin by primary fallout processes and was later remobilized by density currents. 40Ar-39Ar geochronology allowed dating of one succession at 2.24 ± 0.06 Ma, corresponding to the Late Pliocene. Composition of the volcaniclastic material is typical of a transitional high-K calc-alkaline series. The age and chemical composition constrain the provenance of the volcaniclastic rocks from the Southern Tyrrhenian domain. Here, volcanic centres were active during Pliocene time, approximately at the northern end of a volcanic arc formed before the opening of the southernmost part of the sea. This paper shows that a detailed study of volcaniclastic products from the southern Apennines and Calabria can be very useful in collecting new pieces of information on the eruption history of the southern Tyrrhenian domain, since they record additional data not available from the study of exposed volcanic edifices. [ABSTRACT FROM AUTHOR]

Mass transport deposits (MTDs), created by gravity-driven deformation of unlithified sediments, and tectonic mélanges produced by contractional deformation are characterized by a similar chaotic appearance. It follows that distinguishing structures formed by soft-sediment deformation during mass transport from those produced by contractional tectonics can be problematic. In fact, deformation occurring along detachment levels may completely obliterate the original sedimentary fabric. Although a number of advances have been made during recent decades, field criteria for discriminating structures within MTDs that are overprinted by later regional contraction are not readily applicable to all the exposed examples. We address some of these general issues through a detailed case study of the Monte Facito Formation in Italy. This Triassic unit was formed during the Africa–Europe continental separation and, since the Miocene, has been involved in contractional deformation during the construction of the Apennines. The Monte Facito Formation consists of a series of stratigraphically coherent units, separated by chaotic and often deformed intervals, whose origin has been previously attributed to either tectonic or sedimentary processes. An example is provided by a characteristic pebbly mudstone (or 'paraconglomerate') which has been interpreted as either a Triassic gravity-flow deposit, or alternatively, as a product of shearing along regional contractional detachments during the Miocene. This detailed field-based study allows us to recognize structures related to the depositional processes that created these chaotic intervals, and which can therefore be interpreted as MTDs. We also discriminate structures connected to later contractional tectonics that locally produced intense reworking of the MTDs. [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: A mineralogical and geochemical study of clay lithologies and a biostratigraphic analysis of the carbonates from the deep-sea Lagonegro Basin (Southern Apennines—Italy) have been carried out to deduce in general the provenance of clay sediments and their paleoenvironmental conditions and particular to recognize the signature of the Paleocene–Eocene climatic global warming. The analysed succession comprising a wide stratigraphic interval of the Sannio Unit, spanning between Albian to the upper Oligocene–lower Miocene, is exposed near Accettura and Stigliano villages. Eighteen clay samples were analysed by XRD, XRF, SEM, TG-DTA. Their age was framed by biostratigraphic analyses carried out on carbonate sediments. Mineral assemblage of the clay sediments includes quartz, carbonates (calcite and dolomite), feldspars (plagioclase and k-feldspars), hematite, randomly illite/smectite mixed layers with a low illite percentage, kaolinite, discrete illite–muscovite, chlorite, palygorskite and sepiolite. The low illite percentage in randomly illite/smectite mixed layers indicates low diagenetic conditions for the studied successions. These features are unique for the Cretaceous–Tertiary successions of the Lagonegro domain and are particularly significant for the preservation of the native mineralogical assemblage useful to determine the provenance and paleoenvironmental conditions of the clayey sediments. Palygorskite and sepiolite are concentrated in the upper Paleocene–middle Eocene stratigraphic interval and particularly in the upper part of the early Eocene—lower part of the middle Eocene (biozone of Blow P 9–12). Clay sediments rich in palygorskite and sepiolite show a higher P2O5 amount and a lower kaolinite percentage, compatible with warm and arid climatic conditions typical of the global warming event well recorded in the southern tethyan margin. Likely palygorskite and sepiolite formed in lagoonal environment in nearby carbonate platform margins and then they were transported into the Lagonegro Basin as indicated by the well developed habitus of palygorskite. During the Paleogene the Lagonegro Basin and the nearby carbonate platforms represented a key sector the southern paleodomains of the Tethys. The discovery of these minerals gives a contribution to the reconstruction paleoenvironmental conditions of the Tethian paleo-margin during the early–middle Eocene. [Copyright &y& Elsevier]

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]

The main goal of the paper is the reconstruction of a Middle Triassic buildup cropping out in the central part of the Southern Apennines. Middle Triassic reefs of the western Tethys realm are well known in the Northern and Southern Alps. In contrast, few studies of the Anisian–Ladinian carbonate platforms of the southern Apennines are available, due to the diagenetic alteration and tectonic disruption that hinder their paleoenvironmental and stratigraphic reconstruction. In an attempt to fill this gap, and to improve the knowledge on the Anisian–Ladinian carbonates of central Mediterranean area, this research is focused on a carbonate buildup cropping out in the "La Cerchiara" area, Sasso di Castalda (Basilicata, Southern Italy). The buildup, affected by intense tectonic deformation associated with the development of the Apennine thrust and fold belt, was studied using a statistical evaluation of the quantitative microfacies data. The research enabled a reconstruction of the original stratigraphic relationships of the various buildup fragments. A positive linear regression between the sample positions vs the percentage of autochthonous carbonates indicates an increase of the autochthons carbonate toward the top of the succession. The allochthonous fabrics (packstone/wackestone) at the base of the section (Unit IIIa) pass gradually upward into autochthonous (boundstones) facies (Units IIIb, I), consisting of microbialites (clotted peloidal micrite, microbial-derived laminae, and aphanitic micrite), microproblematica and cyanobacterial crusts, with few encrusting skeletal organisms. Statistical data suggest that units IIIa, IIIb, and I are in stratigraphic order while unit II appears to have been moved by tectonic dislocation from its original position at the base of the succession. The absence of metazoan reef framework, and the richness of micro-encrusters, autochthonous micrite and synsedimentary cements, suggest a mud-mound style of growth for the carbonate bodies of the Southern Apennine during the Anisian. [ABSTRACT FROM AUTHOR]