(Table 7) Hiatuses and compressed intervals at DSDP Leg 85 sediments

Biostratigraphic studies using planktonic and benthic foraminifers, calcareous nannofossils, radiolarians, diatoms, and silicoflagellates are summarized for the four main sequences (Sites 572 to 575) collected during DSDP Leg 85 in the central equatorial Pacific. Upper Eocene through Quaternary reference sections were recovered at Sites 573 and 574, and middle Miocene through Quaternary and lower Miocene through Quaternary reference sections were cored at Sites 572 and 575, respectively. Detailed graphic correlation plots suggest that Site 573 may contain as many as nine short hiatuses. Site 572 in the fertile eastern equatorial Pacific is apparently free of hiatuses, and Sites 574 and 575 have hiatuses (two each) only in the compressed upper sections. […]

本研究对赤道中太平洋海域深海钻探计划（Deep Sea Drilling Project, DSDP）第85航次获取的4套核心岩心序列（572至575号站位）开展的生物地层学研究进行了系统总结，所用代用指标涵盖浮游有孔虫（planktonic foraminifers）、底栖有孔虫（benthic foraminifers）、钙质超微化石（calcareous nannofossils）、放射虫（radiolarians）、硅藻（diatoms）及硅鞭藻（silicoflagellates）。573号与574号站位采获了始新统上部至第四系的完整参考剖面；572号与575号站位则分别取心获得了中中新统至第四系、下中新统至第四系的参考剖面。详细图解对比图件显示，573号站位可能存在多达9处短期沉积间断。地处物产富饶的东赤道太平洋海域的572号站位未发现明显沉积间断，而574号与575号站位仅在压实的上部地层段各存在2处沉积间断。……