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In many areas of the Umbria-Marche Apennines, evident traces of huge landslides have been recognized, these probably occurred in the Upper Pleistocene and are conditioned by the tectonic-structural setting of the involved Meso-Cenozoic formations, in a sector of the Sibillini Mountains (central Italy). The present work aimed to focus on a geomorphological hazard in the tectonic-structural setting of a complex area that is the basis of several gravitational occurrences in different types and mechanisms, but nonetheless with very considerable extension and total destabilized volume. An aerophoto-geological analysis and geomorphological survey allowed verification of how the main predisposing factor of these phenomena is connected with the presence in depth of an important tectonic-structural element: the plane of the Sibillini Mountains thrust, which brings the pre-evaporitic member of the Laga Formation in contact with the Cretaceous-Eocene limestone lithotypes (from the Maiolica to the Scaglia Rosata Formations) of the Umbria-Marche sedimentary sequence. Another important element for the mass movements activation is the presence of an important and vast water table and related aquifer, confined prevalently by the different structural elements and in particular by the thrust plane, which has acted and has continued to act, weakening the rocky masses and the overlaying terrains.

This work is a significant contribution to knowledge of the Quaternary and pre-Quaternary morphogenesis of a wide sector of central Italy, from the Apennine chain to the Adriatic Sea. The goal is achieved through a careful analysis and interpretation of stratigraphic and tectonic data relating to marine and continental sediments and, mostly, through the study of relict limbs of ancient landscapes (erosional surfaces shaped by prevailing planation processes). The most important scientific datum is the definition of the time span in which the modelling of the oldest morphological element (the “summit relict surface”) occurred: it started during Messinian in the westernmost portion and after a significant phase during middle-late Pliocene, ended in the early Pleistocene. During the middle and late Pleistocene, the rapid tectonic uplift of the area and the climate fluctuations favoured the deepening of the hydrographic network and the genesis of three orders of fluvial terraces, thus completing the fundamental features of the landscape. The subsequent Holocene evolution reshaped the minor elements, but not the basic ones.

This short note aims to reconstruct the geomorphological hazard scenarios connected to the complex landslide that insists on the territory of Vestea (Civitella Casanova Municipality, in the province of Pescara, Italy). The landslide, active for several decades, probably since the XIX century, is located along a wide valley and starting from its head. It manifests frequently local reactivations with varying movement typology; while total reactivations, taking place in concomitance of particular climate and hydrogeological factors, are more rare.

The recharge of an aquifer is fundamental to evaluate the availability of the resource and for planning its use over the time. In general, indirect methods are widely used, because these are based on the rainfall, evapotranspiration and runoff data. These three parameters are not always simple to evaluate in relation to the possible presence of errors in the available data, malfunction of instruments or difficulty to make a monitoring in relation to the complexity of the area, with consequent uncertainty on the results. In such situations, the use of a direct method could be useful to estimate more accurately the aquifer recharge. A common direct method is based on the analysis of the spring hydrographs, i.e. the discharge monitored at the spring. In this work, a spring hydrograph from the central Apennines of Italy has been analysed in order to estimate the average recharge value feeding the aquifer.

The geomorphological dynamics is an important indicator for understanding processes of river erosion and sediment transport useful to plan appropriate remedial works along the rivers, so as not to modify the fragile equilibrium of the river itself. The present study aims at improve the knowledge on the geomorphological evolution of the Tronto river between the river's mouth and the town of Ascoli Piceno through the analysis of historical maps and aerial photos covering different time spans.The retrieval of historical maps has allowed the reconstruction of the geomorphological evolution of the river bed and of the intervention aimed at river banks protection or, sometimes, for agricultural and industrial use.The interventions along the river beds began around the early 1900s (following the disastrous events of 1897 and 1898), resulting in a strong reduction of the floodplain width, from about 330 up to 210 meters and a rectification of the same with the construction of embankments up to 6 meters above the thalweg; these interventions were more intense at the mouth. The mismanagement of the terminal reach, among other things, after the interventions started in 1978 with the overall reduction in the flow section of the river, will favor the expansion of the flow during the 1992 flood event. The analysis, carried out in a GIS environment, evidenced as the interventions made along the river, have progressively modified almost all of the river reach for a length of over 20 km, reducing the typical cross section of about 50%.

A quantitative and innovative DGSD (deep gravitational slope deformation) assessment method that used integrated remote sensing was tested in the central Apennine mountain range (Italy). The movement rate was calculated for selected test areas using the differential SAR interferometry small baseline subset (SBAS) technique. The selected test areas were previously identified by interpreting both aerial photos and using 32 ERS radar images taken between 1993 and 2000. More than 15 cm of cumulative surface displacement occurred across the Podalla DGSD along the satellite line of sight (LoS). Moreover, the displacement time series showed non-linear deformation rates, which included periods of accelerated movement correlated with strong rainfall. The high estimated Podalla DGSD activity indicates that this type of study should be conducted to monitor the evolution of this phenomenon. In addition, the DInSAR movement rate can be used to improve mapping and identify DGSDs in specific landscapes.

This paper aims to bring to light the possible linkage between karstic phenomena and the human occupation of the Roman site of Carsulae (Tiber basin, Central Italy). Dolines are a typical morphological expression of karst rocks' dissolution and collapse and, usually, they represent a potential hazard for human activities and, in particular, in the care and maintenance of cultural heritage sites. In this study, we observed that the development of a subsidence doline caused severe damage to some archaeological structures at the Carsulae monumental site. According to the results obtained in our investigation, three sites at least with karst dissolution phenomena in the shallow calcareous tufa layer have been identified. One of them subsided probably in Roman times and produced a sharp deformation of the decumanus. In order to understand the evolution of this territory an integrated geomorphological and geophysical survey was carried out. The combination between the information derived from different geophysical techniques, such as: Electrical Resistivity Tomography (ERT), Frequency-Domain Electromagnetism (FDEM), and Ground Penetrating Radar (GPR) clearly pointed out that the calcareous tufa layer is characterized by an irregular geometry and this resulted in the investigated area being affected by karst dissolution in several parts. Four boreholes opportunely located, provided direct information about the depth and the alteration of the calcareous tufa basement and precious calibration data for the geophysical methods. This study contributes to improving our knowledge on the evolution of the Carsulae archaeological site providing a new insight into the adaptation of ancient human societies in this problematic territory.

The geomorphological evolution of the upper Chienti river basin, during the late Pleistocene and the Holocene, was characterized mainly by numerous landslides, strongly affecting the river dynamics, that produced falls, deviations and in some cases total obstructions with the formation of lakes sometimes extending for some kilometres. Moreover, particularly during the Holocene, phytoclastic and phytohermal travertine deposits were deposited in correspondence of steps along the river bed; one of these deposits, by means of radiocarbon dating, has been dated between 8260 ± 100 yr BP and 7740 ± 80 yr BP. Stromatolithic travertine is also present at the base of Holocene channels, slightly incised on the top of the upper Pleistocene alluvial plain. The Neolithic site of Maddalena of Muccia is located on an upper Pleistocene alluvial terrace, at the confluence of the two main tributaries of the river, about 400 m a.s.l. Human presence in this alluvial plain zone lasted from the ancient Neolithic to the Roman period, surely in relation to its strategic position, connecting the Adriatic and the Tyrrhenian slants of the chain. The richest and most important remains, found at just 50 cm under the field level, belong to the ancient and recent Neolithic and to the Aeneolithic, and have been collocated between the VII and the V millennium BC, using C14. During the archaeological excavations carried out by the Archaeological Superintendence of the Marche region, testimonies reveal a local economy that was primarily based on animal breeding, cereal cultivation, fishing and deforestation. The study has evidenced that the river incision process, usually started in other areas at the beginning of the Holocene, was strictly limited by the presence of steps and barrages that reduced sedimentation flows towards the initial sectors of the valleys within the calcareous Apennine ridge. The generalized deposition of travertine along the riverbeds and within the minor channels that developed at the top of the upper Pleistocene alluvial plains also produced a sort of armature of the riverbed thus limiting further erosion processes. The resumption of linear erosion coincided with the natural erosion of the dams previously caused by landslides, and above all, (starting from about 4500 yr BP) with the rapid decline of the travertine deposition due mainly to climatic conditions.

On August 24th 2016 a Mw=6.0 earthquake hit central Italy, with the epicenter located at the boundaries between Lazio, Marche, Abruzzi and Umbria regions, near the village of Accumoli (Rieti, Lazio). Immediately after the mainshock, this geological survey has been focused on the earthquake environmental effects related to the tectonic reactivation of the previously mapped active fault (i.e. primary), as well as secondary effects mostly related to the seismic shaking (e.g. landslides and fracturing in soil and rock).This paper brings data on superficial effects and some preliminary considerations about the interaction and possible relationship between surface faulting and the occurrence of Deep-Seated Gravitational Slope Deformation (DSGSD) along the southern and western slope of Monte Vettore.

The present work aims to establish relationships between shoreline historical variations (close to the river mouths) and slope dynamics on mountain and hilly areas: these are considered as fundamental physiographic units of the Adriatic central Italy. The study deals about the deltaic system of the Chienti river, which is representative of the deltaic systems of the main Marchean rivers. Goal is to recognize possible geomorphological indicators of climatic variations during late Holocene. Debris flows on the Sibillini Mts were analysed and interpreted. Their activation can be associated with: late Pleistocene-early Holocene deglaciation, with regard to the oldest phenomena; agricultural, forestry and grazing activities during the Late Middle Ages, even though evidence of climatic conditioning is also present. Moreover, some important landslide phenomena on the high hilly areas were examined: historical data demonstrated an intense post-Middle Age activity (XVth-XVIIIth centuries) related to the strong rainfall increase as a consequence of climatic worsening.Dans cette note, sont interprétées quelques formes mineures du paysage physique, utilisables en tant qu'indicateurs géomorphologiques des variations climatiques de l'Holocène supérieur. La création et l'évolution de ces formes sont liées à la circulation superficielle et souterraine d'importantes quantités d'eau. Les processus analysés se réfèrent aux zones représentatives de l'organisation géomorphologique des trois unités physiographiques fondamentales de l'Italie centrale adriatique : les régions montagneuses, la bande péri-adriatique des hautes collines et la plaine côtière.La première zone appartient au massif des Monts Sibyllins, dans l'Apennin central d'Ombrie-Marches. Les sommets dépassent fréquemment 2000 mètres d'altitude et atteignent 2476 mètres au Mont Vettore. Le substrat géologique est formé par la célèbre "succession d'Ombrie-Marches" (Trias supérieur - Aquitanien), constituée d'unités lithostratigraphiques calcaires, marno-calcaires et marneuses. La disposition structurale est caractérisée par des plis à vergence orientale marquée, des chevauchements et des failles normales. Le substrat rocheux est souvent oblitéré par la présence de dépôts morainiques, de dépôts fluvio-torrentiels et d'accumulations d'éboulis stratifiés. Dans cet espace, l'analyse géomorphologiques de détail et les enquêtes historiques approfondies effectuées sur les nombreuses coulées torrentielles, a rendu possible l'établissement des cinématiques fondamentales. L'attribution chronologique probable des phénomènes les plus anciens à la fin du Pléistocène supérieur et au début de l'Holocène, a été établie sur la base des corrélations des dépôts avec les formes alluvionnaires, glaciaires et périglaciaires environnantes. Leur déclenchement est associé à la déglaciation de la fin du Pléistocène - début de l'Holocène. Les phénomènes plus récents sont en grande partie attribués à l'époque médiévale et post-médiévale. Les sources historiques témoignent de la récurrence des ces processus à partir du XIIème siècle. Cependant, les événements principaux, en intensité, étendue et dommages, se sont réalisés pendant la période comprise entre les XVème et XIXème siècles. Le facteur déclenchant prédominant des phénomènes du bas Moyen Âge semble être l'anthropisation des versants, même s'il existe des indices d'une augmentation des précipitations par rapport à la période précédente. Pour la période suivante, qui va jusqu'à la moitié du XIXème siècle, la cause principale peut être reliée au refroidissement du climat et à l'augmentation des précipitations (en particulier neigeuses), favorables à des remontées significatives des niveaux piézométriques. Ils ont débuté au milieu du XVIème siècle et se sont prolongés pendant trois siècles environ. Le déclenchement des processus du XXème siècle est lié au retour de l'activité agricole sur des espaces qui avaient déjà été occupés depuis la période médiévale et la Renaissance. Leur fonctionnement qui a débuté au XIXème siècle et a persisté jusqu'à la moitié du XXème siècle, est dû aussi à l'absence ou à la faible efficacité des ouvrages d'aménagement hydraulique et forestier. Dans la bande péri-adriatique, sont analysés les aspects morpho-dynamiques du relief du Mont de l'Ascension (1110 mètres d'altitude), formé par un puissant corps sablo-conglomératique intercalé avec des sédiments argileux (Pliocène moyen). La structure est monoclinale (pendage de 15 à 20° vers l'est-nord-est). Les éléments géomorphologiques fondamentaux sont des mouvements de terrain, des processus d'érosion hydrique accélérée (en majorité des bad-lands) et les restes d'un important dépôt de glacis (âge compris entre 41640 ans ± 1260 B.P. et 22680 ans ± 170 B.P. – B. GENTILI et al., 1998). L'étendue originelle de ce glacis était de plus de 10 km², l'épaisseur de ses formations dépassait les 30 mètres. La topographie régulière du glacis, dont les dépôts ont été mis en place à la fin du Pléistocène, a été dégradée par la dynamique holocène, particulièrement intense au sud et à l'est. Les analyses géomorphologiques et les enquêtes historiques ont fourni des données intéressantes pour les principaux mouvements de terrain du dernier millénaire, dont les principaux facteurs de mise en place, d'activité et de contrôle sont caractérisés par la superposition de plusieurs aquifères séparés par des couches argileuses, par les caractéristiques géotechniques des argiles du substrat, par des niveaux piézométriques significatifs, par le jeu de la tectonique, et par l'approfondissement rapide du réseau hydrographique. L'action morphodynamique des mouvements de terrain qui a été intense à l'époque post-médiévale, entre les XVème et XVIIIème siècles, peut être attribuée à l'aggravation du climat pendant cette période.Dans la bande côtière c'est dans l'embouchure fleuve Chienti qu'est analysée l'évolution morphodynamique. Ce delta est constitué en majorité de graviers calcaires et marno-calcaires. Ce cours d'eau, long de 91 km, prend sa source sur le versant septentrional des Monts Sibyllins et a un bassin hydrographique, de 1250 km2. Il est un des principaux cours d'eau des Marches et il coupe perpendiculairement les principales unités structurales de l'Apennin d'Ombrie-Marches. À partir des sources historiques, on a pu établir que la ligne de rivage a connu, près de l'embouchure, une avancée relativement forte jusqu'à la fin du XVIIIème siècle. Cette avancée se renforce entre 1810 et 1935 (3,2 m/an). En revanche, depuis 1935, on observe un recul du delta (3,5 m/an). Dans la zone urbaine de Porto Civitanova, située au nord de l'embouchure, une étude détaillée de la ligne de rivage durant les trois derniers siècles, montre une avancée moyenne pendant la période 1705-1935 (environ 1,1 m/an) suivie d'une forte accélération à partir de 1935 (2,8 m/an). Cette accélération peut être liée à la présence d'ouvrages portuaires, commencés en 1932 et achevés en 1938. Dans l'interprétation complexe des processus responsables de l'évolution de l'embouchure du Chienti, comme dans celle d'autres cours d'eau des Marches, il est tenu compte non seulement du facteur anthropique, déjà signalé plusieurs fois par les auteurs, mais aussi de l'action retardée dans le temps des conditions climatiques froides et humides post-médiévales. En effet, la forte avancée de la plage entre 1810 et 1935 trouve son explication dans l'arrivée à l'embouchure de quantités considérables de matériaux dont la texture favorise les processus de sédimentation (graviers). Leur provenance est la conséquence de l'érosion des dépôts détritiques de la zone des montagnes et des hautes collines par l'augmentation pluviométrique significative du "Petit Âge glaciaire" (M. PINNA, 1984).

The study, developed over a wide mountain sector of the central Apennines (Italy), highlights the role of Deep Seated Gravitational Slope Deformations (DSGSD) in the evolution of a mountain portion of the Chienti river valley. Radiocarbon dating and geomorphological considerations, testify that a lateral spreading, developed on a large scale, has triggered large landslides in correspondence of the thalweg. These phenomena have repeatedly dammed the river bed (certainly since the end of the late Pleistocene) creating temporary lakes which lasted also for a long time. The high seismicity and the persistence of conditions favorable to the development of gravitational phenomena, in an area currently occupied by an important communication route, attest to the high degree of risk present in this sector of the Apennine.

The study of geomorphological hazards in tourist areas has been addressed only recently, mostly because in areas of high touristic value any risk for excursionists or for simple nature lovers represents a strong conditioning factor to the fruition and therefore to the economy of an entire area. The geomorphological hazard can turn into a considerable risk, if one takes into account the increasing human pressure even in remote areas. The development of tourism, in fact, brings an increasing number of people to discover and attend both areas prone to hazards for some time, both in areas where these hazards are being increased. The complexity and multiplicity of these changes require necessarily a greater attention not only for a correct comprehension of natural phenomena but mostly for their possible interactions with tourism attendance and fruition. Based on previous experiences, also as a result of research projects funded by the Italian Ministry for the University and the Research (MIUR). A study on the natural hazards related to the touristic fruition in the area of Frasassi Cave in the Marche region (central Italy) is following presented.

In the axial zone of the Umbria-Marche Apennines, several fault-bounded intermontane basins (i.e., Colfiorito, Norcia, Castelluccio and Leonessa) were generated at the end of Lower Pleistocene. The analysis of the master fault of the basins, the relicts of planation surfaces and the drainage network arrangements, allowed us the improvement of knowledge on the Pleistocene morphotectonic evolution of those basins. Morphometry and geostatistics of the topography have been performed to obtain indexes suitable for assessing the role of faults displacements on the landscape development. Furthermore, a gravimetric analysis realized along some basins has furnished new data on their sedimentary infill. The basins are filled by Pleistocene to Holocene fluvial-lacustrine coarse-grained deposits, and the bedrock consists of Jurassic to Miocene limestone and marls belonging to the Umbria-Marche succession. Several historical and instrumental highly destructive earthquakes occurred in this area: January 14, 1703 (X MCS, M = 6.6); September 19, 1979 (Ms = 5.9, focal depth of 6–8 km); September 26, 1997 (Mw = 6.0, focal depth of 6–8 km). Faults and earthquake focal mechanisms are compatible with a predominant NE–SW extension, but strike-slip and reverse mechanisms have been also documented. The fault activity appears to have had a predominant role in controlling the sedimentation processes inside the intermontane basins, as well as in controlling their Pliocene to Quaternary evolution.

This work assessed the geomorphological evolution and erosion rates in a small clayey catchment of Tyrrhenian central Italy, providing chronological constraints for the fluvial deposits of the area for the first time. The study area is the catchment of the Formone stream, a left tributary of the Orcia River (Tuscany, Italy). A 5 km-long section of the valley, up to its confluence with the Orcia, was studied. It has an area of ca. 12 km 2 and elevations between ca. 300 and 600 m a.s.l. Two soil samples have been radiocarbon dated. One was located at the top of a fluvial terrace (~ 20 m above the present thalweg), and the other was located near the water divide of a small tributary catchment: they yielded ages of 2780 ± 40 and 14,050 ± 70 yrs B.P., respectively. These chronological constraints allowed us to reconstruct the geomorphological evolution of the area through topographic and GIS analyses, and to estimate late Quaternary erosion rates. The ages provided a chronological reference for the terraced fluvial deposits of the Formone and the upper Orcia catchments. The resultant erosion rates are consistent with those in the literature both for the Tyrrhenian side of central Italy and for Mediterranean Europe. Moreover, the results confirmed that very intense erosion processes occurred as a consequence of the Pleistocene–Holocene climatic change, as observed in the peri-Adriatic belt of central Italy.

The proposed study case is rather interesting from a scientific-technical and social-economic point of view, since it is tied to conditions of high geological risk for inhabited, originally medieval or earlier, town of Montefalcone Appennino, where frequent damage, sometimes catastrophic are generated. Integrate geological, geomorphological and numerical analyses were carried out to understand the evolution and the kinematics of different types of gravitational movements. These remarkable phenomena are located on the relief of Falcone Mount in central Italy, where the towns of Montefalcone Appennino and Smerillo are builted. On the basis of field surveys, geomorphological interpretation and numerical analyses, turn out to be specific for falls, slides and deep-sited gravitational deformations, the phenomena were analysed, attempting to reconstruct both a geomorphological and a numerical models, checking whether or not their correspondence. The different deformations regard the arenaceous-calcarenitic-conglomeratic bodies superimposed onto marly clays or weathered levels of the pelitic-arenaceous turbidites; the kinematics are further illustrated and interpreted in detail.

The present work deals on an example of large landslide at Marina di Altidona, along the central Italy Adriatic coast, representative of many situations observed along the sea-cliff areas of the Marche and the Abruzzo regions; all these phenomena are located in areas which correspond to the most uplifted sectors during the Quaternary. The data collected, allow to hypothesize a past activation of a huge mass movement along a deep sliding surface, presently submarine. It was related to the high relief connected to the strong tectonic uplift of the middle-upper Pleistocene, to which a probable high seismicity was also associated. The validation of the geomorphological model has been carried out by applying a Finite Difference Numerical Code (FLAC_2D) to a huge gravitational movement and, in particular, by characterizing the dynamic evolution along significant transects.

During the last 30 years of studies in the field of mass movements located in the calcareous-marly and marly-sandy Apennines (Umbria-Marches and Latium-Abruzzi regions), over to a large number of landslides with different dimensions, even a lot of deep-seated gravitational slope deformations (DSGSDs) have been recognized and analysed. These phenomena are also located in that sector of central Italy affected by a cold climate during the past and actually temperate (central Apennine chain).

The ancient village of Montelparo (Marche region, Central Italy) is affected by a large translational mass movement. The relief is modeled on arenaceous and arenaceous-pelitic units overlying pelitic-arenaceous terrains; the bedding strata form a gently dipping monocline. The translational slide is about 1100 m long and 500–700 m wide. The upper boundary between the stable area and the sliding mass is marked by a large active trench near the hilltop. The main sliding surface is located at a depth ranging between 65 and 100 m, in the politic-arenaceous unit. We studied the mechanism of the slope instability along the stratigraphic contact between a rigid arenaceous unit and an underlying ductile pelitic unit. The uncovering of the contact caused by the intense downcutting processes of the river at the hill foot during the Holocene, favoured the onset of the movement. This was enhanced by the fractured bedrock and especially by the jointing. We created a numerical model based on the finite differences code FLAC_3D by using a specific approach for mesh generation. The model suggests a further enlargement and deepening of the trench, and a sliding direction not aligned with the slope dip direction. Failure in the model concentrates at and around the main trench, all the other elements staying in an elastic state and inducing a rigid sliding. The model shows that both the failure onset and the current evolutionary state can be explained by the geological and static conditions of the slope.

The present work deals with a large area of the Marche–Abruzzi monoclinal relief which is made up of a clayey sediment succession with sandy–conglomeratic levels alternating at varying stratigraphic heights. The east-verging monocline was generated by an intense Quaternary tectonic uplifting. It differs approximately in the west-east and in the southern directions forming three wide morphostructures. The deep fluvial down-cutting disjointed the monoclinal relief into a succession of high hills which give the area a typical cuesta morphology, with fronts facing the western quadrants. The present study aims at contributing to the knowledge of recent slope morphodynamics by analyzing the spatial distribution and state of activity of fast hydro-erosion processes and superficial mass movements. Correlations are made between these phenomena and the morphotectonic and lithological features of the various sectors in the area, with particular reference to agricultural land use. The present research underlines how the badlands represent the most spectacular form of fast erosion, whereas the landslide phenomena, which affect the prevalently loamy–clayey eluvial–colluvial covers, are the most widespread processes. Despite the distribution, density and recent, or current, evolutionary trends, are generally associated with different morphostructural features of the various sectors of the area, they prove to be strictly controlled by agricultural exploitation and by the connected techniques and types of cultivation.