晚第四纪冲绳海槽北段CaCO_3含量的时空变化及其控制因素  

SPATIAL-TEMPORAL VARIABILITY OF CaCO_3 CONTENTS OF THE CORE SEDIMENTS FROM THE NORTHERN OKINAWA TROUGH DURING LATE QUATERNARY AND ITS CONTROLLING FACTORS

作　　者：李军[1] 李凤业[2] 周永青[1] 齐金成[3] 厉玉乐[3] 

机构地区：[1]青岛海洋地质研究所,青岛266071 [2]中国科学院海洋生态与环境重点实验室,青岛266071 [3]中国地质大学,北京100083

出　　处：《海洋地质与第四纪地质》2004年第2期15-22,共8页Marine Geology & Quaternary Geology

基　　金：国家自然科学基金资助项目(40176020;40106006);中国科学院知识创新工程项目(KZCX2 207)

摘　　要：对取自冲绳海槽北段的6个沉积岩心进行了CaCO3含量、粒度和铀系同位素分析,结合氧同位素数据和海槽其他钻孔的相应结果,探讨了冲绳海槽北部晚第四纪以来CaCO3含量的垂向与横向变化特征。结果表明,冲绳海槽北段沉积总体上表现为全新世CaCO3含量高、晚更新世CaCO3含量低的"大西洋型"碳酸盐演化特征,但冲绳海槽北段和中部的碳酸盐演化特征并不一致,海槽内西坡、槽底和东坡的不同部位其演化特征也存在较大差异。碳酸盐含量的变化与沉积物粒度特征密切相关,晚第四纪冲绳海槽碳酸盐演化的时空差异是多种因素相互作用的结果。Based on the analysis of carbonate contents, grain-size and U-serial isotope, we discussed the spatial-temporal variation of the carbonate content in the core sediments collected from the northern Okinawa Trough. The results show that carbonate content in the sediments was high during Holocene and relatively low during late Pleistocene, which is the pattern of the “Atlantic-Type” carbonate cycle. But there are very large differences between the features of the carbonate evolution in the different parts of northern and central Okinawa Trough, according to the comparison of mean grain-size results. According to the information in the paper as well as data collected from others, we suggested that the spatial-temporal variation of carbonate contents in the Okinawa Trough was mainly controlled by several factors, in which the sedimentation and sediment source are the most important, and the event sedimentation may “disturb” or“counteract” the carbonate accumulation in the trough. Moreover, the paleo-Kuroshio ocean current may have played a role to some extent.

关 键 词：晚第四纪 CaC0.含量 容重法 事件沉积 冲绳海槽 时空变化 

分 类 号：P736.21[天文地球—海洋地质] P534.63[天文地球—海洋科学]