Inventory of Italian Rocky Coasts Aimed at the Improvement of the Knowledge of their Evolution

Abstract

The establishment of a working group on rocky coast in Italy in 2006 have permitted to organize several activities (meetings and excursions) and therefore to prepare an inventory of Italian rocky coasts. At these activities have participated the authors of the present abstract, which have indicated from time in time the characters of the visited coasts performed in these two years. Such coasts was selected in order to have a wide inventory where cliff in different geological regimes (tectonically stable, volcano-tectonically active) and lithology (limestone, terrigenous, volcanic) are represented. The aim of this group is to improve the knowledge of the factors having a role in the evolution of the rocky coasts, also in view of the 7th IAG/AIG Conference as well as in the efficacy of the answers to give at the coastal management. In Italy rocky coasts are the most diffuse interface between land and sea, however their characters are various in the form and size of the cliff (subaerial and submerged), in the nature and mechanical condition of the outcropped litotype, in the geological and geomorphological inheritance (i.e. thrust, sea notches) or in the type of the anthropogenic action (activity and/or engineering structures). The analysis of such characters, integrated in some case with a continuous monitoring, have permitted to define some models able to account for the geomorphological evolution of the cliffs, according to the predominant litotipe (hard or weak or loose), its profile (i.e. the presence of a shore platform) and, at last, the coastal regime. The other factors could be quicken or slacken the rate of retreat, but they are not relevant in the development of the model. The role of climate in terms of rainfall and temperature is roughly the same (Mediterranean Group), even if we considered cliffs far away more than 1000 km.