BIOSTRATIGRAPHIC STUDY OF THE ILAM AND GURPI FORMATIONS BASED ON PLANKTONIC FORAMINIFERA IN SE OF SHIRAZ, IRAN

The study of planktonic foraminifera of the Ilam and Gurpi formations at Sarvestan area (SE of Shiraz) enables me to find the most standard biozones defined in mediterranean regions, especially Tethysian domain. Seven biozones were determined. Biozones I (Dicarinella concavata zone) and II (Dicarinella asymetrica zone) belong to the Ilam Formation and indicate the Late Coniacian-Early Santonian and Middle-Late Santonian, respectively. Biozones III to VII were determined from the Gurpi Formation. Biozones III (Globotruncanita elevata zone), IV (Globotruncana ventricosa zone) and V (Globotruncanita calcarata zone) represent the Early, Middle and Late Campanian, respectively. Biozones VI (Globotruncanita stuarti zone ) and VII (Gansserina gansseri zone) suggest the Early and Middle Maastrichtian, respectively. In the Late Maastrichtian, due to decreasing in water depth at the study area, Abathomphalus mayaroensis zone defined in Tethysian domain, was not recognised.