The recent evolution of the Sinis region (western coast of Sardinia, Italy) on the basis of new radiometric data of the pliocenic volcanism

Abstract

The present paper focuses on the relationships between Pliocene volcanic activity and geomorphological evolution of Sinis region (western Sardinia, Italy). Plio-Pleistocene volcanic activity plays a key role in the recent landscape evolution. Morphological evolution has been reconstructed on the basis of chronological data obtained on different volcanic episodes.
In order to constrain the evolution model, Ar/Ar radiometric studies have been carried out on volcanic episodes of Sa Mulargia and Catalano island. The landscape is characterized by smooth morphologies and a poorly defined hydrographic network; volcanic relief shows relief inversion processes. These processes produced a roughly NS trending drainage in the western sector, favored by extensional faults that conditioned the geomorphological features commonly observed in the coastline. Several ponds in the eastern Sinis area are likely related to the interaction of morphogenetic processes favored by tectonic activity and sea level fluctuation and variation of Tirso river, the main river of Sardinia.