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Transmission Electron Microscopy Tomography (TEMT) stands as a novel and alternative tool to tridimensionally model the nano-scale pores of rocks. In this study it is flanked with traditional Mercury Capillary Injection Porosimetry (MICP), Nitrogen adsorption Porosimetry (NP) and Scanning Electron Microscopy (SEM) analysis, to test a sample belonging to an Upper Triassic dolostone cropping out in Northern Calabria. MICP revealed low values of porosity and permeability, 2.3% and the 0.11 mD respectively. Nanopores account for the 94% of the pore volume, whereas the remaining 6% is represented by micropores. The integrated MICP and NP pore size distribution (PSD) shows the presence of a dominant pore diameter population coincident with 50 nm, with minor peaks at diameters of 12 μm, 850, 25, 13, 6, 2 nm. However, since the PSD peaks of the two techniques do not match, a comparison of the two curves is necessary to better characterized the overlapping area. SEM imaging analysis showed the presence of nano-scale intercrystalline and intracrystalline pores. The first corresponds with the spaces among dolomite crystals and, as suggested by the NP analysis, shows a wedge/slit morphology. The second appears with a prevailing polygonal section or as tight microfractures. Since SEM provides exclusively two-dimensional images, the morphology and development of these pores was obtained through TEMT 3D reconstruction. The 3D model showed the presence of open cavities, fractures and blind/isolated pores. Cavities cross the entire dolomite crystals and can present a constant (sub-prismatic pores) or variable channel section (funnel-shaped pores) that can reduce its aperture, as observed, of also more than a ten factor (e.g. from 300 nm to 20 nm). Fractures, commonly developing on the existing cleavage surfaces, cut the crystal faces for 300–350 nm, reducing its aperture (maximum of 20–30 nm) from the edge towards the inner part of the crystal. Lastly, blind/isolated pores can assume diameters and thickness of 250 nm. They show a sub-cubic morphology and, can be filled by solid, liquid or gaseous inclusions.

Clastic wedges deposited in deep-marine turbidite systems along the circum-Mediterranean region represent key tectonic elements that record the structural growing of the Apennine orogenic belt over the Adria margin. One of these clastic wedges is represented by the Agnone Flysch turbidite succession deposited in the Lagonegro-Molise foredeep basin in the early Messinian, for which the depositional facies and the related processes, as well as the sandstone and mudstone composition are poorly known. A combined sedimentology and sedimentary petrology study has been conducted on this turbidite succession that provides new insight to define the basin architecture and the provenance of the Agnone Flysch during late Miocene. Facies analysis suggests that this turbidite succession is constituted by depositional lobes that were emplaced in a sector of the basin showing a variable morphological confinement with frontal and lateral slope on which turbidite deposits onlapped. Consequently, this topographic context controlled the lateral and vertical distribution of turbidite facies, which record the effects of erosive processes, as well as impact, rebound and reflection processes, in turn related to the flow deceleration induced by structurally-controlled basin confinement. Detailed sandstones compositional analysis indicates a complex unroofing history that reflects structural changes in the source rock units and depositional basin physiography. By combining the sandstone composition with information deduced from the X-ray diffraction (XRD) patterns after thermo-chemical treatments (heating and ethylene glycol treatments), it was possible to explain and predict the sedimentary evolution and geological processes affecting fine grained sediments and, thus, the relationship developed between source area and sedimentary basin. In particular, clay minerals data show that Agnone Flysch experienced an early diagenetic condition as showed by the occurrence of the I/S R0 and I/S R1 on the XRD pattern of the glycolated specimens. The sandstone composition (mainly quartzofeldspathic) shows an increase in the metamorphic rock fragments and a decrease of sedimentary lithics up-section. This compositional trend records, together with the paleocurrents data, a derivation of this material from a mountain range located in the Tyrrhenian sector and from the Calabrian arc terranes.

Chemical and mineralogical signatures of mudstones from the Agnone Flysch turbidite successions (late Tortonian to early Messinian) deposited in the Lagonegro-Molise foredeep basin reveal new insight for the sedimentary evolution of the southern Apennines during late Miocene. Geochemical and mineralogical signatures of the Verrino and Poggio Villanelle members of the Agnone Flysch mark a complex sedimentation history testifying to a multi-source area probably due to structural changes and depositional basin physiography. The studied mudstones show chemical variations in term of Ca vs. Si and Al. Mineralogical analyses confirm a decrease of carbonate minerals and an increase of silicate phases passing from Verrino Member to Poggio Villanelle Member samples. Compositional data of the mudstone samples of both members mainly record a derivation from felsic rocks due to the Calabrian terranes unroofing. Poggio Villanelle Member samples further show an enrichment in Cr, Ni, Fe e Mg in accordance with higher chlorite content suggesting a mafic supply probably related to an ophiolitic source successively exposed. Thus, those trends based on chemical and mineralogical data suggest a change in relative abundance of a detritus characterized by different compositions through time and space. Whole rock geochemistry of the studied mudstones indicate that they are from the first-cycle sediments. Palaeoweathering processes in source areas were moderate as shown by CIA (Chemical Index of Alteration) and CIA’ (modified Chemical Index of Alteration) values of the mudstones of both members (Verrino and Poggio Villanelle members). The trends observed in the paleoweathering diagrams suggest source areas characterized by moderate weathering in non-steady-state conditions which have changed toward the upper portion of the sedimentary succession. Those changes are mainly related to the geodynamic conditions of the source areas where active tectonism allows erosion of all zones within weathering profiles developed on source rocks. The paleocurrent data and the compositional analysis of the mudstones and sandstones indicate a provenance (supply) from the western, north-western, and south-western sectors of the basin where carbonate platforms and magmatic, metamorphic and sedimentary rocks cropped out.

Computational simulation is widely used in companies to perform analysis and improve the quality of products and projects. Most of these analyses are carried out using software that uses the Finite Element Method, which allows to obtain answers to numerous engineering problems. In this study, two examples of application to the study of tunnels of the Finite Element Method using the Geostru Software "GFAS - Geotechnical F.E.M. Analysis System" are proposed. The case of a tunnel excavated inside a granite rock massif was analyzed, first determining the state of stresses in the cavity contour through a theoretical method and comparing these results with those obtained in the software. Then, by means of finite element modeling, the settlements induced by the excavation were determined. Finally, the problem of tunnel excavation in a viscoplastic rock mass is presented and the authors propose a comparison of the analytical and numerical method.

Although groundwater is a strategic source in volcanic islands, most hydrogeochemical research on this topic has been focused on volcanic activity monitoring, overlooking general hydrogeological aspects. The same applies to one of the most studied volcanoes in the world, Stromboli Island (Italy). Here, we provide a hydrogeological scheme of its coastal aquifer, retrieving inferences about its potential use as a water supply source and for optimizing monitoring protocols for volcanic surveillance. Starting from the hydrogeochemical literature background, we analyzed new data, acquired both for volcano monitoring purposes and during specific surveys. Among these, there were saturated hydraulic conductivity measurements of selected rock samples and precise determinations of water table elevations based on GNSS surveys of wells. We identified a ubiquitous thin lens of brackish water floating on seawater and composed of a variable mixing of marine and meteoric components, inlets of hydrothermal fluids to the aquifer are basically gases, mainly CO2. Based on its hydrogeochemical character, the coastal aquifer of Stromboli could be used as a water supply source after desalinization by reverse osmosis, while the wells located far from the seashore are the most interesting for volcano monitoring, because they are less disturbed by the shallow geochemical noise.