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Rockfall events represent significant hazards for areas characterized by high and steep slopes and therefore effective mitigation controls are essential to control their effect. There are a lot of examples all over the world of anthropic areas at risk because of their proximity to a rock slope. A rockfall runout analysis is a typical 3D problem, but for many years, because of the lack of specific software, powerful computers, and economic reasons, a 2D approach was normally adopted. However, in recent years the use of 3D software has become quite widespread and different runout working approaches have been developed. The contribution and potential use of photogrammetry in this context is undoubtedly great. This paper describes the application of a 3D hybrid working approach, which considers the integrated use of traditional geological methods, Terrestrial Laser Scanning, and drone based Digital Photogrammetry. Such approach was undertaken in order to perform the study of rockfall runout and geological hazard in a natural slope in Italy in correspondence of an archaeological area. Results show the rockfall hazard in the study area and highlights the importance of using photogrammetry for the correct and complete geometrical reconstruction of slope, joints, and block geometries, which is essential for the analysis and design of proper remediation measures.

A detailed stratigraphical-structural survey combined with classical geological mapping has been performed in the\ud northern Chianti Mts, part of the Northern Apennines Orogen (central Italy). The study area can be subdivided in\ud different tectonic and depositional units: (i) the widely outcropping Tuscan Nappe (middle/late Lias–earliest\ud Miocene), thrusted to the west by (ii) Ligurian units (Cretaceous–Eocene) and unconformably covered by (iii)\ud post-nappe deposits (Pliocene–Pleistocene). The Chianti Mts are structured as a mega-antiformal fold,\ud dissected by WSW-ENE transversal lines and by NNW-SSE normal faults linked with the exhumation of the\ud Northern Apennines Range, developing a basin/ridge structure. As results, (i) a new improved stratigraphic\ud frame is here proposed; (ii) several tectonic and stratigraphic domains have been newly recognised; (iii) a large\ud area characterised by severe internal deformation has been recognised and mapped as an imbricate fan thrust\ud system, linked with transversal lines

A detailed geological map at 1:50,000 scale of the Marecchia Valley and adjoining areas\ud (Northern Apennines, NA, Italy) is presented here. The Marecchia Valley represents a\ud geological ‘unicum’ for the NA and it has been the focus of scientific debate for a long time,\ud due to the occurrence in the area of the ‘Coltre della Val Marecchia (CVM)’, a complex stack\ud of allochthonous and semi-allochthonous units emplaced in a foredeep basin during the Late\ud Miocene to Early Pliocene. In order to clarify the geological evolution for this area, the\ud lithostratigraphic relationships and the tectonic framework have been studied, allowing\ud better understanding of the complex relationships between tectonics and sedimentation.\ud The main result has been a new evolutionary framework for this sector of the orogen during\ud the Late Miocene-Early Pliocene. Several new findings about the geological-structural setting\ud and stratigraphy, result from the geological map presented here. These are overall supported\ud by stratigraphic and tectonic evidence, which suggest time and modes of the CVM\ud allochthonous emplacement within the Messinian-early Pliocene foredeep successions.\ud Relationships between the allochthonous and autochthonous formations allowed recognition\ud of two different bodies in the CVM, gravitationally emplaced following different trajectories\ud and timing

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The need to obtain a detailed hydrogeological characterization of the subsurface and its interpretation for the groundwater resources management, often requires to apply several and complementary geophysical methods. The goal of the approach in this paper is to provide a unique model of the aquifer by synthesizing and optimizing the information provided by several geophysical methods. This approach greatly reduces the degree of uncertainty and subjectivity of the interpretation by exploiting the different physical and mechanic characteristics of the aquifer. The studied area, into the municipality of Laterina (Arezzo, Italy), is a shallow basin filled by lacustrine and alluvial deposits (Pleistocene and Olocene epochs, Quaternary period), with alternated silt, sand with variable content of gravel and clay where the bottom is represented by arenaceous-pelitic rocks (Mt. Cervarola Unit, Tuscan Domain, Miocene epoch). This shallow basin constitutes the unconfined superficial aquifer to be exploited in the nearly future. To improve the geological model obtained from a detailed geological survey we performed electrical resistivity and P wave refraction tomographies along the same line in order to obtain different, independent and integrable data sets. For the seismic data also the reflected events have been processed, a remarkable contribution to draw the geologic setting. Through the k-means algorithm, we perform a cluster analysis for the bivariate data set to individuate relationships between the two sets of variables. This algorithm allows to individuate clusters with the aim of minimizing the dissimilarity within each cluster and maximizing it among different clusters of the bivariate data set. The optimal number of clusters “K”, corresponding to the individuated geophysical facies, depends to the multivariate data set distribution and in this work is estimated with the Silhouettes. The result is an integrated tomography that shows a finite number of homogeneous geophysical facies, which therefore permits to distinguish and interpret the porous aquifer in a quantitative and objective way.

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