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通过对中法合作“马可·波罗”航次在南海南部陆坡采集的MD05-2894柱状样(7°2.25′N,111°33.11′E,水深1982m)进行浮游有孔虫定量分析,结果表明,末次冰消期距今16.0～14.9calkaBP之间,浮游有孔虫Pulleniatinaobliquiloculata(斜室普林虫)的丰度急剧降低至几乎为零.这次普林虫低值事件在南海南部普遍存在,发生时间介于17.0～14.8calkaBP之间,可以作为地层划分对比的良好标志.对浮游有孔虫表层种Globigerinoides和次表层种P.obliquiloculat的壳体进行Mg/Ca比值分析,再造表层和次表层海水的温度进一步揭示末次冰消期普林虫低值事件时,表层海水的温度变化不大,而次表层海水的温度明显下降～2℃,使得温跃层深度随之变浅.这次普林虫低值事件在时间上相当于H1的气候变冷事件,反映了南海南部热带海区上部水体垂向结构的巨大变化,为研究末次冰消期变暖过程中的快速气候变化提供了重要依据.
The quantitative analysis of planktonic foraminifera was carried out on the MD05-2894 column (7 ° 2.25’N, 111 ° 33.11’E, water depth 1982 m) collected by Sino-French cooperation “Marco Polo” on the southern slope of the South China Sea. The results showed that the abundance of the planktonic foraminifera Pulleniatina obliquiloculata dropped sharply to almost zero between 16.0 and 14.9 calkaBP at the end of the last ice extinction period. Exists between 17.0 ~ 14.8calkaBP, which can be used as a good marker for stratigraphic comparison.Analysis of Mg / Ca ratio of Globigerinoides and P.obliquiloculat shell of planktonic foraminifera, The temperature of sub-surface seawater further revealed that the temperature of surface seawater did not change much in the low ice event of the last ice-cooling event, but the temperature of sub-surface seawater decreased obviously by ~ 2 ℃, making the depth of the thermocline shallow. The suboptimal events in the subtropical zone are equivalent to the climatic cooling events of H1 in time, reflecting the great changes in the vertical structure of the upper part of the tropical South China Sea in the southern part of the SCS, providing a basis for studying the rapid climate change during the last ice- weight in accordance with.