Rapporti fra morfologia e tettonica della pianura cuneese

Relationships between the morphology and the neotectonic features of the Cuneo plain

Abstract

The relationships between the morphology and neotectonic features of the Cuneo Plain and its afferent valleys are examined. A close correspondence is indicated between residual morphologies (glacis, inselbergs, terraces) and areas that are either free of recent tectonic activity or undergoing recent uplifting with fossilisation of their shape, or areas where erosion is taking place, but its tectonic nature is of recent date, with the result that its destructive effects have not yet been able to make themselves fully apparent. The Quaternary rock pattern on the site is also of neotectonic origin. Causes of this type must be at least partly responsible for the displacement of the escarpment-plain boundary due to the Bagnolo and Bracco glacis (NW sector). The Saluzzo salient (between the Po and Varaita Valleys) and the Roracco salient correspond to uplift areas, while the large “gulfs” formed by the debouching of the Valle Maira and, to a lesser extent, the Valle Grana, are located upstream from areas undergoing subsidence. A series of complex modifications has taken place in the river system in the Quaternary era, due to neotectonic activity. Examples of such changes include the capture of the Pesio, already completed, the capture of the Po, which is still in progress, and the differences between the Po and Tanaro hydrographical basins. Evidence can be put forward to uphold the working hypothesis that the capture of the Tanaro took place after the last glacial period.