The Lower Paleogene Biostratigraphic Scale of the Northern Pacific Based on Deep-Water Benthic Foraminifera

Abstract

Based on the stratigraphic distribution of benthic foraminifera in the lower bathyal–abyssal sediments uncovered by boreholes drilled under the framework of the Deep Sea Drilling Project (DSDP) and Ocean Drilling Project (ODP) in the Northern and Southern Pacific, the Lower Paleogene biostratigraphic zonal scale based on deep-water benthic foraminifera is proposed. The proposed scale includes eight subdivisions: six zones and two subzones. The boundaries of the zonal subdivisions are determined by biotic events (appearance or disappearance (extinction)) of stratigraphically important taxa and are correlated to the zonal scales based on planktonic foraminifera and calcareous nanoplankton. Most of these events are considered to be subglobal.