末次冰期以来南海南部千年尺度的古海洋学  

MILLENNIAL SCALE PALEOCEANOGRAPHIC VARIATIONS FROM THE LAST GLACIAL IN THE SOUTHERN SOUTH CHINA SEA

作　　者：王良[1] 刘传联[1] 

机构地区：[1]同济大学海洋地质国家重点实验室,上海200092

出　　处：《海洋地质与第四纪地质》2008年第4期85-91,共7页Marine Geology & Quaternary Geology

基　　金：国家自然科学基金项目(40676029);国家重点基础研究专项(2007CB815901);创新研究群体科学基金(40621063)

摘　　要：对南海南部MD05-2896柱状样22.8kaBP以来的深海沉积物进行了浮游有孔虫和颗石藻化石定量分析。通过转换函数、特定有孔虫属种含量及比值和颗石藻Florisphaera profunda百分含量等探讨了南海南部海水表层温度、上部水体结构、初级生产力以及碳酸盐溶解作用等变化趋势和周期性。结果表明:18kaBP以前及10kaBP以来,海水表层温度较高,碳酸盐溶解作用较强,温跃层营养跃层较深,初级生产力较低。18～10kaBP冰期时,海水表层温度最低,碳酸盐溶解作用变弱,营养跃层和温跃层变浅,初级生产力较高。频谱分析结果显示,22.8kaBP以来的气候变化具有明显的周期性,以类D/O事件的千年尺度周期为主,其中最主要的周期为1500年。Quantitative analyses of planktonic foraminifera and coccoliths were carried out on the sediments from core MD05-2896 in the southern South China Sea. Abundance variations of index species of planktonic foraminifera and Florisphaera profunda, and the technique of FP-10E and SIMMAX-28 were used to reconstruct paleoceanographic changes in the sea surface temperature, upper ocean water structure, primary productivity and carbonate dissolution and their periodicity in the southern South China Sea over the last 22.8 ka. The result shows. （1） during the earlier period from 22.8 to 18 ka and later period since 10 ka, the sea surface temperature increased, carbonate dissolution reinforced, the depth of thermocline and nutricline deepened and the primary productivity was relatively lower; （2） from 18 to 10 ka, the sea surface temperature was lowest, carbonate dissolution weakened, the depth of thermocline and nutricline shoaled and primary productivity was highest; and （3） during the last 10 ka, the sea surface temperature increased, the depth of thermocline and nutricline deepened and the primary productivity reduced, and car- bonate dissolution increased after 7 ka. The spectrum frequency analysis result demonstrated that the climate change had obvious cyclicity fluctuation over past 22.8 ka. The dominant period is 1 500 years, which is similar to millennial D/O event. Besides,the climate change also has some small periods such as the periods of 700-900 years and 500 years.

关 键 词：颗石藻 浮游有孔虫 海水表层温度 海水上层结构 初级生产力 南海 

分 类 号：P736.22[天文地球—海洋地质]