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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.

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.