CRETACEOUS TEMPERATE-TYPE CARBONATE PLATFORMS FROM NORTHERN (SARDINIA) AND SOUTHERN (APENNINES, APULIA) TETHYAN MARGINS

Studies of the Cretaceous sequences of the Nurra region (NW Sardinia, Italy) identified Senonian rudist-dominated deposits whose bioclastic lithofacies show a change from chlorozoan-chloralgal sediments (with a limited contribution of non-skeletal grains) to foramol sensu lato deposits. Comparative analysis carried out on coeval limestones in depositional systems on opposite margins of the Mesozoic Mediterranean Tethys (Sardinia and Apennines-Apulia respectively) help to clarify the specific conditions that controlled rudist growth and their change from chlorozoan versus foramol-assemblages in a very different depositional context from that characterizing the lower Cretaceous carbonate platforms.