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Recent technological advances are leading numerous researchers and professional users to the adoption of photogrammetric products for a wide range of geoscientific applications. Especially, drone-based Structure-from-Motion (SfM) photogrammetry is often applied as a high-resolution topographic modelling technique with advantages in terms of time and cost when compared to traditional surveying approaches. The aim of this work, carried out within the GeoArchaeo Sites Project, is to investigate the adaptability of drone-based surveys, even with a targetless approach, and to estimate bathymetrical accuracies in shallow waters. The approach was applied on an underwater site to show the potential for the digitalization and monitoring of an archaeological coastal geosystem in central Italy. Specifically, this work has compared the photogrammetric surveying capability of two drones including a Phantom 4 RTK (‘P4RTK’) and a low-cost Mavic Mini 2 (‘MM2’) and an Olympus TG-6 (underwater camera) for a site submerged with a maximum depth of ∼1.6 m. The assessment of the drone SfM-based products was performed through area-based and point-wise comparisons. Specifically, the area-based were assessed through an underwater photogrammetric survey obtained by acquiring images by an operator snorkeling along a portion of the site of interest. The point-wise comparison was performed using data acquired with a Global Navigation Satellite System (GNSS). This study demonstrates that coupling SfM-photogrammetry and UAS-based surveys have potential to define submerged topography. In particular, the imagery acquired with the P4RTK survey can produce dense 3D models of the underwater surface with high resolution (about 0.02 m) and bathymetric measurements with a vertical accuracy ranging between 0.06 and 0.29 m for the area-based and point-wise analysis, respectively. Thus, the approach adopted and tested involving the use of a P4RTK has the potential to reduce constraints and limitations in terms of GCPs distribution and measurement. Also, with such an approach the need for qualified operators for underwater photogrammetric workflow can be avoided.

L’Itinerario interessa la Campania centrale e orientale, tra il basso Sannio e l’alta Irpinia, in un territorio dominato da una morfologia collinare, che racchiude un patrimonio geologico interessante e di grande variabilità. Il percorso (Fig. 7.1) prevede la partenza da Telese Terme, nella bassa Valle del Calore beneventano, e la conclusione a Fontanarosa, in provincia di Avellino, con una distribuzione degli stop su circa 300 km, meglio se ripartiti in due giorni, con pernottamento a Vallesaccarda. Il paesaggio attraversato si presenta piuttosto articolato, sviluppandosi in prevalenza tra aree vallive e di alta collina, con rilievi raramente aspri e che non superano i 1.000 m di quota. Va, a questo proposito, rilevato che nella stagione invernale le frequenti nevicate rendono impegnativa la percorrenza della viabilità interna. L’abbigliamento consigliato è quello escursionistico, da valutare in relazione alla stagione, ma è buona norma avere con sè un impermeabile perché, soprattutto d’estate, non sono rari i temporali pomeridiani.

In landslide prone areas, the magnitude of events is related to recurring rainfall intensity. In a large sector of the Sannio Apennines (Southern Italy), predictive mapping of recurrent shallow landslides was obtained by combining deterministic and probabilistic predictive approaches. The deterministic approach was performed using TRIGRS model and, subsequently, different predictive scenarios were proposed for different probabilistic return periods of the rainstorm events. Two new introduced indexes indicates the good performance of the model. . © Springer International Publishing Switzerland 2015.

In this paper, the authors argue that integration of the hydrological model for landslide-prone areas should proceed under a soft geovisual communication in order to mitigate the uncertainty involved in downscaling rainstorm hazard mapping and geocomputational tracking. In this respect, examples of geovisualized spatial patterns for Terminio-Tuoro area affected by damaging landslide events is given by the rainstorm hazard index (RHI)–kriged probability map. These findings should contribute to improving the information base needed to implement and monitor a sound strategy for warning, forecasting and planning landslide hazard. . © Springer International Publishing Switzerland 2015.

Surface mapping, GPS surveys, T-Lidar surveys, boreholes, seismic profiles, and HVSR measurements were used to study the mechanisms of sediment transport along the Mount Pizzuto earth flow in southern Italy. The earth flow has several kinematic zones, with transitional areas marked by changing structural styles, from compressional structures (thrusts) upslope to extensional structures (normal faults) downslope. We relate sediment discharge at these transitional zones to internal strain. The results suggest that during surge events, flow acceleration starts within the head and propagates downslope inducing a cascade effect between kinematic zones. During surge events, the average sediment discharge is nearly constant, and a change from sliding to flowing allows propagation of movement towards the toe. During slow movement, kinematic zones are independent and sediment discharge varies along the flow. In general, the velocity profile and the structural style are controlled by the basal slip surface. The implications are: i) sediment discharge is not constant but is a function of the earth flow activity, ii) during surge, earth flow material behaves similar to an incompressible fluid, and iii) the distribution of surface structures can provide information about the geometry of the slip surface and the velocity profile. Additionally, earth flows with a well-defined neck seem to be more likely to surge with respect to those without. © 2017 Elsevier B.V.