摘要
对西菲律宾海Ph05-5柱状样190ka以来钙质超微化石进行了氧碳同位素分析.研究结果表明,钙质超微化石δ18O值在末次间冰期(MIS5e)和全新世明显低于末次冰期(MIS5d～2)和倒数第二次冰期(MIS6).超微化石δ18O值与浮游和底栖有孔虫δ18O值都呈明显的正相关关系,但超微化石δ18O平均值比浮游有孔虫Globigerinoides rubberδ18O平均值高0.431×10-3,比Neogloboquadrina dutertreiδ18O平均值低0.410×10-3,而这三者又远远低于底栖有孔虫Cibicides wull-erstorfi的δ18O平均值.超微化石δ13C值变化阶段性特征明显,并与该孔超微化石绝对丰度变化趋势极为相似,二者共同反映出西菲律宾海大约从190ka到110ka的MIS6和大约MIS5e期,表层海水初级生产力相当稳定且显著低于其他各时期;大约从MIS5d期开始表层初级生产力显著上升,初级生产力的这一高值一致持续到约25ka左右的末次冰期;在25ka以来的MIS1、2期,表层初级生产力有所下降,但仍高于190ka到110ka的MIS6和MIS5e期.
The piston core Ph05-5 recovered from the West Philippine Sea （16. 049 3°N,124. 344 8°E, water depth 3 382 m） was used to study the δ^18O and δ^13C variations of calcareous nannofossils. The δ^18O values of calcareous nannofossils were obviously lower in Holocene and the last interglaciation than those in the last and the penultimate glaciation. During the last 190 ka the nannofossil δ^18O values were positively correlated with those of planktonic and benthic foraminifera from the same core. But the average δ^18O value of nannofossils was 0. 431 ×10^-3, higher than that of planktonic foraminifera Glohigerinoides rubber, and was 0. 410× 10^-3 , lower than that of planktonic foraminifera Neogloboquadrina dutertrei. All the above three average δ^18O values were much lower than those of benthic foraminifera Cibicides wullerstorfi. The change of nannofossil δ^13C values showed similar trends with the absolute abundance of calcareous nannofossils in core Ph05-5, which also indicates the primary productivity variations in the West Philippine Sea. The primary productivity stayed at a stable hut relatively low level at MIS 6 and MIS 5e. There was an abrupt rise at the beginning of MIS 5d for the primary productivity which retained high value until 25 ka BP. The primary productivity showed a slight decline during MIS 2 and MIS 1, but still higher than that of MIS 6 and MIS 5e.
出处
《地球科学（中国地质大学学报）》
EI
CAS
CSCD
北大核心
2008年第2期183-189,共7页
Earth Science-Journal of China University of Geosciences
基金
中国科学院知识创新工程项目(NoKZCX3-SW-233)
国家自然科学基金重点项目(No90411014)
国家自然科学基金面上项目(Nos40506013,40506015)
国家重点基础研究发展计划“973”项目(No2007CB815903)
中国科学院海洋研究所知识创新工程青年人才领域前沿项目(No2007-10)
关键词
西菲律宾海
钙质超微化石
氧碳同位素
初级生产力
West Philippine Sea
calcareous nannofossils
oxygen and carbon stable isotopes
primary productivity.
