Evoluzione morfotettonica recente della zona compresa tra la testata del T. Nure e la Val d'Aveto (Appennino Piacentino)

Recent morphotectonics evolution of the zone between T. Nure valley and Aveto valley (Piacenza Apennine)

Abstract

The neotectonic features of a zone between the high Nure valley and the Aveto valley (Piacenza Apennine) are here analyzed. The study involved the following research: a geological survey at the scale 1:5000; a morphometrical analysis of the drainage network with definition of some significant parameters; a mesostructural detailed analysis on the fracture domains in the examined zone; a geomorphological analysis (carried out by photo-interpretation) to determine the morphostructural elements. In particular, the structural analysis makes it possible to define the presence of three main phases of deformation; two of them are transcurrent with a maximum compression axis with a direction respectively NE and NNW, and the other, more recent, is normal. The drainage pattern and the morphologic frame have generally suffered from the different strain fields which have successively affected the zone. In particular, the study of the fluvial drainage network, using morphometric parameters already known in literature and with the introduction of others, is useful to establish the possible correlation between the development of the surface drainage and the structural elements. The comparative analysis of the achieved results allows to define a plan of the recent morphostructural evolution of the zone and to date the observed structural elements. Some of the determined tectonic lines are probably active also in the periods following the last Würm glaciation. Finally, the geodynamic meaning of the normal regime is briefly discussed: it is possible to associate it to the marked phenomenon of uplift which is in progress today.