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本文对冲绳海槽北部Rd一82孔浮游有孔虫N.dutertrei和Rd一86孔N.dutertrei及G.sacculifer的氧同位素记录进行了分析。Rd一82孔浮游有孔虫的氧同位素组成可清晰地划分氧同位素1一4期,跨越地质时代0一71ka;Rd一86孔可划分氧同位素1一4期及5a-5c亚期,跨越地质时代为0一110ka。根据氧同位素变幅分析,末次冰期极盛时冲绳海槽北部可能有黄河和长江的淡水影响,其影响强度Rd一82孔强于Rd一86孔。晚更新世以来,黑潮流一直影响着本区,冰期时黑潮流主流线向东转折段向南偏移,根据现有资料至少南移0.34个纬度。此外,在氧同位第2期,即末次冰期极盛期内发生一个短暂的气候回暖事件,该事件发生在21一20kaB,P,之间。
This paper deals with a 82-hole planktonic foraminifera N Rd in the northern part of the Okinawa Trough. dutertrei and Rd-86 holes N. dutertrei and G. Oxygen isotope records of sacculifer were analyzed. Rd a 82-hole planktonic foraminifera oxygen isotope composition can be clearly divided into oxygen isotopes 1 to 4, across the geological era 0 71ka; Rd 86 holes can be divided into oxygen isotopes 1-4 and 5a-5c sub-phase, spanning Geological era is 0 a 110ka. According to the analysis of oxygen isotope amplitude, the northern part of the Okinawa Trough during the last ice age may have the influence of fresh water from the Yellow River and the Yangtze River. The influence strength of Rd-82 is stronger than that of Rd-86. Since the late Pleistocene, the trend of the Kuroshio current has affected the area. During the glacial period, the main trend of the Kuroshio current moved eastwards to the south and shifted southwards by at least 0.34 latitude based on available data. In addition, a brief climatic warming event occurred in the second phase of oxygen isotope, that is, the extreme period of the last ice age, which occurred between 21 and 20 ka BP.