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The CROP-11 deep seismic profile across the central Apennines, Italy, reveals a previously unknown, mid-crustal antiform here interpreted as a fault-bend fold-like structure. The seismic facies and gravity signature suggest that this structure consists of low-grade metamorphic rocks. Geomorphological, stratigraphic and tectonic evidence in the overlying shallow thrusts suggests that this structure developed in early to mid- Messinian time and grew out of sequence in late Messinian– Pliocene time. The out-of-sequence growth may reflect a taper subcriticality stage of the Apenninic thrust wedge, which induced renewed contraction in the rear.

An analysis of multichannel seismic reflection data was conducted focusing on the comparison between the Messinian Salinity Crisis (MSC) and Plio-Quaternary (PQ) evolution of the eastern Sardo-Provençal and northern Algero- Balearic basins and related margins in the West Mediterranean Sea. Both basins were completely opened during the MSC and their well-defined seismic stratigraphy is very similar in the deep parts. The primary difference between these two basins is due to their different pre-MSC extensional history, including the opening age and the stretching factors. These factors influenced the occurrence of post-MSC salt tectonics on these margins.

A large seismic dataset has allowed us to regionally study the West Mediterranean Sea with particular focus on the West Sardinia and South Balearic continental margins and adjacent oceanic basins. The main seismic and geological evidences are related to the presence of the Messinian Trilogy in the deep basins and lower slopes, and coeval erosional truncation on the intermediate and upper margins. During the deposition of the upper Messinian sequence (UU), a thin salt layer has been highlighted, thanks to the high resolution of recent profiles. This salt layer, precipitated during the initial re-filling of the Mediterranean Sea, has been correlated to an erosional surface on the lower slope inner the UU and interpreted as the effect of a temporary sea level drop. The underlying salt layer (MU) shows halokinetic deformations in the deep basins which started since the Upper Messinian and developed principally during the Pliocene, sometimes until the Present, as testified by sea bottom piercings. The halokinetics has affected by different intensity, on the base of its original thickness, of the sediments and water load, and of the proximity of the lower slopes, where the sliding of salt toward the deep basin determined compressive stress and enhancing diapirism.

Fresh water availability has recently become a serious concern in the Italian Apennines, as various activities rely on a predictable supply. Along the ridge between Scansano and Magliano in Toscana, in southern Tuscany, the situation is further complicated by contamination of the nearby alluvial aquifers. Aquifers locally consist of thin fractured reservoirs, generally within low-permeability formations, and it can be difficult to plan the exploitation of resources based on conventional techniques. An integrated study based on geological data investigated the link between tectonics and groundwater circulation, to better define the hydrological model. After the regional identification of fault and fracture patterns, a major structure was investigated in detail to accurately map its spatial position and to understand the geometry and properties of the associated aquifer and assess its exploitation potential. The subsurface around the fault zone was clearly imaged using ground probing radar, two-dimensional and three-dimensional resistivity tomography, and three-dimensional shallow seismic surveys. The vertical and horizontal contacts between the different geological units of the Ligurian and Tuscan series were resolved with a high degree of spatial accuracy. Three-dimensional high-resolution geophysical imaging proved to be a very effective means of characterising small-scale fractured reservoirs.