Palaeo-shorelines of the historic period, Sant'Antioco Island, south-western Sardinia (Italy)

In the near coastal area of Palmas Gulf, a bone and ceramics fragment-rich pericoastal beach rock, chronologically referable to the Imperial Roman age between Tiberius and Claudius (1940 ± 20 BP), has been studied. The results of this study fit the new predicted glacio-hydro-isostatic model of Lambeck et al., and agree with similar data from other Sardinian sites that show almost no vertical tectonic mobility during the Late Holocene. The study of a new stratigraphic section along the western coast of Sant'Antioco Island has identified the inner margin of a wave cut platform with fossils, referred to MIS 5.5 at + 7.5 m, highlighting a relative tectonic stability since the upper Pleistocene for this area. The geomorphological context of Palmas Gulf continental shelf shows a buried palaeo-riverbed referred to MIS 2, and a coastal palaeo-system related to the Holocene sea level change between −15 and −25 m. These features are typical of the conservative style of low tectonic mobility areas.