High-resolution Pliocene-Pleistocene biostratigraphy of Site 959, eastern equatorial Atlantic Ocean

Abstract

High-resolution calcareous nannofossil biostratigraphy was examined from Cores 159-959C-1H through 8H in 20-cm intervals for the Ocean Drilling Program in the eastern equatorial Atlantic Ocean. Well-preserved marker species occur continuously and are relatively abundant in Hole 959C. Six zones (CN10 through CN15) are identified. All calcareous nannofossils are well preserved. Late Neogene (Pliocene-Pleistocene) sediment is dominated by Florisphaera profunda, Gephyrocapsa caribbeanica, G. oceanica, Gephyrocapsa spp., Reticulofenestra pseudoumbilica, R. minutula, and small Reticulofenestra. The sedimentation rate varies from 0.4 cm/k.y. to 13.5 cm/k.y. This strong variations are related to disconformities. The lowest sedimentation rate occurs in the early late Pliocene (Subzone CN12a; 0.4 cm/k.y.), and the highest sedimentation rate in the early early Pleistocene (Subzone CN13b; 13.5 cm/k.y.). The average sedimentation rate from Cores 159-959C-1H through 8H is 1.5 cm/k.y.