Eocene-Oligocene Boundary Reference Sections in the Pacific

Abstract

This chapter discusses Eocene–Oligocene boundary reference sections in the Pacific. In over 15 years of deep-sea drilling the Eocene–Oligocene boundary was recovered in relatively few deep sea drilling project (DSDP) sites in the Pacific Ocean located primarily in the equatorial region and the Southwest Pacific. The differences in species ranges clearly indicate the necessity for separate high and low latitude reference sections and a means of calibrating them independent of microfossils that is possible for the Eocene–Oligocene boundary by using the oxygen isotope record. Thus, based on core recovery fossil preservation, biostratigraphic, and stable isotope studies sites 292 and 592 represent the best candidates for the Eocene–Oligocene reference sections to date for the equatorial and Southwest Pacific.