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对南海南部 ODP1143站近百万年来钙质超微化石进行了氧、碳同位素分析,结果表明,超微化石δ18O比值与浮游有孔虫和底栖有孔虫δ18O比值呈同步变化,但超微化石δ18O值较浮游有孔虫δ18O值平均高1.869‰,比底栖有孔虫δ18O值平均低3.855‰。超微化石δ13C值与浮游有孔虫和底栖有孔虫δ13C值之间相关性不明显,三者存在系统差异.超微化石δ13C值要比底栖有孔虫δ13C值平均高0.756‰,比浮游有孔虫δ13C值低0.460‰。在氧同位素14～8期之间,超微化石δ13C值有一明显的高值段.另外,本次研究还发现超微化石δ13C值变化与 Florisphaera profunda百分含量有很好的对应关系,指示超微化石δ13C值可以作为表层海水古生产力变化的标志.
Oxygen and carbon isotopic analysis of calcareous nannofossils in ODP1143 station in the southern South China Sea for nearly a million years showed that the δ18O ratio of the nannofossils changed synchronously with the δ18O ratio of planktonic and benthic foraminifera, The δ18O value of fossils is 1.869 ‰ higher than that of planktonic foraminifera δ18O, and 3.855 ‰ lower than the average δ18O value of benthic foraminifera. The correlation between δ13C value and the δ13C value of planktonic foraminifera and benthic foraminifera was not obvious, and there was systematic difference among them.The δ13C value of the microfossils was 0.756 ‰ higher than the δ13C value of the benthic foraminifera, Than the planktonic foraminifera δ13C value of 0.460 ‰. Δ13C values of the microfossils have a distinctly high value between the oxygen isotopes 14 and 8. In addition, the δ13C value of the microfossils shows a good correspondence with the percentage of Florisphaera profunda in this study, Micro-fossil δ13C values can be used as a sign of changes in paleoproductivity of surface waters.