摘要
根据对台湾岛以东海域A-24C,A-50C岩芯中放射虫化石的分析结果,并借助WP3岩芯有孔虫、δ18O曲线分析、测试资料,对两岩芯地层作了对比与划分。结果显示:两岩芯的上部(A-24C为0～30cm,A-50C为0～35cm)属全新世沉积;下部(A-24C为30～234cm,A-50C为35～163cm)属晚期更新世沉积。两岩芯中放射虫丰度、分异度的变化与黑潮主流线的摆动密切相关。末次冰期时的低海面导致黑潮主流线移至研究区(125°E)以东,放射虫丰度、分异度出现低值,有的层位出现零值,而随着海面回升,黑潮逐渐移至现在的位置,放射虫的丰度、分异度出现高值。另外综合该区分析资料,推算两岩芯的平均沉积速率为A-24C岩芯全新世3cm,晚期更新世12.6cm;A-50C岩芯全新世2.9cm,晚更新世12.4cm。晚期更新世沉积速率均大于全新世。
In this paper, the strata of cores A 24C and A 50C in the area east of Taiwan Island are correlated and divided based on the analysis results of radiolaria fossils in cores A 24C and A 50C and the analysis and test data of foraminifera and δ 18 O curve in core WP 3. It is shown from the correlation results that the upper parts of the two cores (A 24C 0~30 cm, A 50C 0~35 cm) belong to the Holocene sediment, and the lower parts (A 24C 30~234 cm, A 50C 35~163 cm) belong to the late Pleistocene sediment. The changes of radiolaria abundance and diversity in the two cores are closely related to the swing of Kuroshio main stream. The low sea level in the last glacial period resulted in the Kuroshio main stream moving to the area east of 125 °E and the occurrence of low radiolaria abundance and diversity, even the occurrence of zero abundance at some stratigraphic horizons, but with the rise in sea level, the Kuroshio main stream shifted to the present position to result in the occurrence of high radiolaria abundance and diversity. In addition, it is inferred by synthesizing the analysis data for the area that the average sedimentation rates for the two cores are 3cm in the Holocene and 12.6cm in the late Pleistocene for core A 24C and 2.9cm in the Holocene and 12.4cm in the late Pleistocene for core A 50C, respectively, which indicates that the sedimentation rates in the late Pleistocene are all greater than those in the Holocene.
出处
《海洋科学进展》
CAS
CSCD
北大核心
2002年第3期60-67,共8页
Advances in Marine Science
基金
十五"国际海底区域研究开发资助项目--利用微体
超微化石释读结壳的生长年代
生长速率及生长环境(DY105-01-04-8)
