Faunal Turnover across the Cretaceous/Tertiary Boundary in Kabir-Kuh, Southwest of Iran


In order to determine changes across the K/T boundary and to detect foraminiferal biozones a well preserved section of the Gurpi Formation in north of Kabirkuh, southwest of Iran was investigated. Maastrichtian biozones of Caron (1985) were all recorded. Moreover, Li & Keller's (1988a) CF 1 to CF4 zones were also recorded. Paleocene layers were divided into two biozones; Parasubbotina pseudobulloides and Parvularugoglobigerina eugu-bina zones based on Toumarkine & Lutherbakher (1985). As the index species for uppermost Maas-trichtian and lower Danian biozones were recorded the sedimentation across the KTB seems to be continuous though research to locate zone P0 is still continued. Statistical studies of foraminifera show that 2/3 of the species extinct below and at the KTB and 1/3 remain in the lower Danian. The extinct fauna are of large size and ornamented while the survivors are of small size and without ornament-ation and cosmopolitan. This indicates that the extinction model was similar to that of type section.