Evoluzione morfotettonica nel basso Appennino pavese-piacentino: l'esempio del T. Gualdora, affluente del T. Tidone (Piacenza, Italia settentrionale)

Abstract

The morphological evolution of a small basin in the hillside area of the Northern Apennines in the Piacenza Province was governed by local differential tectonic movements occurred within a general uplifting regime. Remnants of summit and slope paleosurfaces, as well as several landslides caused by undercutting processes are evidence of an advanced evolution on one hand and, on the other, of a new general river erosion, as a consequnce of recent uplifting movements of the Apennines range. This new erosional conditions seem to involve the Gualdora river basin in a lesser extent, because the morphology of the basis shows less evolved feaures than those of surrounding basins. We hypothesise that this situation may be explained by assuming that the lesser evolution of the Gualdora basin is the effect of a lesser uplift of this area owing to a fault system. The faster evolution of the surrounding basins linked to a higher relief energy, allowed a strong headward erosion that pushed inward the Gualdora basin divide. Local tectonic movements may explain the anomalous meandering of the central portion of the river.