(Table T1) Benthic foraminfera stratigraphy of ODP Hole 199-1218A and 199-1219A sediments@en

We investigated benthic foraminiferal assemblages from Sites 1218 and 1219, Ocean Drilling Program Leg 199, to understand the abyssal response of the eastern equatorial Pacific to the Oligocene climate. Globocassidulina subglobosa, Oridorsalis umbonatus, Gyroidinoides spp., Cibicidoides spp., and Pullenia spp. are common in the lower Oligocene, whereas Nuttallides umbonifer, a dominant species in carbonate corrosive deep water, often dominates the upper Oligocene assemblage at both sites.本研究针对大洋钻探计划（Ocean Drilling Program, ODP）第199航次1218与1219站位的底栖有孔虫组合开展调查，旨在阐明东赤道太平洋深渊环境对渐新世气候的响应。渐新统下部地层中，亚球形球袋虫（Globocassidulina subglobosa）、具脐突背壳虫（Oridorsalis umbonatus）、回转虫属未定种（Gyroidinoides spp.）、似瓷虫属未定种（Cibicidoides spp.）及普林虫属未定种（Pullenia spp.）较为常见；而作为碳酸盐溶蚀型深水环境优势种的具脐突努特虫（Nuttallides umbonifer），则常主导两个站位渐新统上部的有孔虫组合。