Mesozoic and Cenozoic calcareous nannofossils recovered by Deep Sea Drilling Project Leg 71 in the Falkland Plateau region, southwest Atlantic Ocean.

Abstract

Thick sections of sediments of Oxfordian-lower Tithonian, Albian, upper Turonian-Maestrichtian, and middle Eocene-Oligocene assemblages are reasonably diverse for these latitudes and generally well preserved. Long sections of Santonian to lower Campanian, middle Eocene, and Oligocene strata add substantially to the record of nannofossiliferous sediments recovered by the previous cruise to the area. High-latitude provincial forms are common in the Cretaceous and Tertiary sections and have prompted the proposal of new zones or subzones for the Barremian-Aptian, Albian, Coniacian-Turonian, and Oligocene. Severe climatic condtions limit post-Oligocene coccolith assemblages to fewer than one dozen species; thus zonations remain virtually unworkable for that part of the column in this area. -Author