New geological data on the Cassino intermontane basin, central Apennines, Italy

This paper presents the outcome of photogeological analysis, field survey as well as borehole correlation, to add new data concerning the intermontane Cassino basin and define facies and thickness of its Quaternary deposits. The investigated area is located in the end sector of the Latina Valley, Southern Lazio and belongs to the Lazio-Abruzzi domain. With a maximum extension of 250 km(2) and a NW-SE trend, this paleo-lake was created by lava flows from the Roccamonfina volcano, which barred the Latina Valley. The lacustrine facies were described during the 1960s but available bibliographic data about its spatial distribution and its relationship with the Mesozoic-Cenozoic bedrock are scarce. The thickness of Quaternary deposits has been deeply influenced by inherited paleomorphologies. Indeed the geological reconstruction of the basin has outlined the presence of an underlying horst and graben structure. This latter obscured the contractional tectonics originated by the orogenetic deformation, even if new structures have been recognized at the foot of Montecassino Hill. We infer that a key role has been performed by the Roveto Valley-Atina-Caserta fault, between Atina and San Pietro Infine.