Cenozoic Radiolaria in the western North Atlantic, Site 603, Leg 93 of the Deep Sea Drilling Project.

Abstract

Eight Cenozoic radiolarian zones were recognized in samples from two holes at Site 603, drilled on the lower continental rise off North America during Leg 93 of the Deep Sea Drilling Project. Paleocene to early Eocene radiolarian zones and early to late Miocene radiolarian zones were recognized in sediments from Holes 603 and 603B. In addition, a new Paleocene Bekoma campechensis radiolarian Zone is defined by the interval between the first morphotypic appearance of B. campechensis and the B. campechensis- B. bidartensis evolutionary transition. This zone is immediatey below the B. bidartensis Zone and has previously been discussed as a Paleocene 'unnamed zone' by other investigators. A hiatus between Neogene and Paleogene sequences was also recognized in the radiolarian faunas. -from Author