Cretaceous planktonic foraminifera in sediments of the Ontong Java Plateau

Cretaceous planktonic foraminifers from Ocean Drilling Program (ODP) Leg 130 consist of two age groups: one dominantly Aptian in age and the other dominantly Maastrichtian. The oldest dated sediments from Ontong Java Plateau occur at ODP Site 807 and are assigned to the early Aptian Globigerinelloides blowi Zone. The assemblage correlates closely with Aptian foraminifers from Deep Sea Drilling Project (DSDP) Site 289 and a younger Aptian assemblage from DSDP Site 288 where drilling ended before reaching basement. Planktonic foraminifers from ODP Site 803 suggest a late Aptian to early Albian age and are overlain by radiolarians of late Albian age. These ages are in conflict with a radiometric age of about 90 Ma for basement at the site. The dominantly Maastrichtian group occurs at Site 807 and consists of poorly preserved, mostly small-sized specimens that range in age from perhaps the latest Campanian to the Cretaceous/Tertiary boundary. Age assignments are made difficult by pervasive dissolution and resedimentation that extends into the Paleogene. […]