冲绳海槽南部沉积物碎屑锆石U-Pb年代学特征及物源示踪意义  

Characteristic of detrital zircon U-Pb geochronology in the southern Okinawa Trough and its implication for sediment provenance

作　　者：朱博文 曾志刚[1,2,3] ZHU Bowen;ZENG Zhigang(Key Laboratory of Marine Geology and Environment,Institute of Oceanology,Chinese Academy of Sciences,Qingdao 266071,China;University of Chinese Academy of Sciences,Beijing 100049,China;Laboratory for Marine Mineral Resources,Qingdao National Laboratory for Marine Science andTechnology,Qingdao 266237,China)

机构地区：[1]中国科学院海洋研究所海洋地质与环境重点实验室,青岛266071 [2]中国科学院大学,北京100049 [3]青岛海洋科学与技术国家试点实验室海洋矿产资源评价与探测技术功能实验室,青岛266237

出　　处：《海洋地质前沿》2022年第1期14-23,共10页Marine Geology Frontiers

基　　金：国家自然科学基金“西太平洋俯冲体系中岩浆活动及其对热液物质供给的制约”(91958213);中国科学院国际合作局对外合作重点项目“冲绳海槽热液活动成矿机理及其沉积效应”(133137KYSB20170003);山东省泰山学者工程专项“特聘专家资助计划项目”(ts201511061);中国大洋协会项目课题“海底多金属硫化物及金属软泥的成矿机理”(DY135-G2-1-02)。

摘　　要：冲绳海槽南部作为冲绳海槽全新世以来沉积速率最快的区域,其沉积物记录了物源区、黑潮及东亚季风演化等多方面的信息。通过碎屑锆石年代学,对冲绳海槽南部H4-S2孔沉积物开展了物源示踪研究。结合核密度估计图解(Kernel Density Estimation,KDE)、累积年龄分布(Cumulative Age Distribution,CAD)及其相关性分析,进行了研究层位和潜在物源区的可视化分析与相似性检验,揭示了研究样品中2个层位碎屑锆石的年代学特征及物质来源。物源分析结果显示,近200 a来冲绳海槽南部沉积物中的碎屑锆石记录了东海陆架、长江以及兰阳河来源的物质,指示了除兰阳河外,东海陆架及长江在晚全新世对冲绳海槽南部的沉积物质来源具有重要贡献。The southern Okinawa Trough is the area with the fastest deposition rate since the Holocene, and its sediments record the evolution of provenance, Kuroshio and the East Asian monsoon. In this paper, detrital zircon U-Pb geochronology is used to study the provenance of H4-S2 sediments in the southern Okinawa Trough. By means of Kernel Density Estimation(KDE), Cumulative Age Distribution(CAD) and correlation analysis, the visual analysis and similarity test for potential provenances of two layers of sediments are carried out for the trough, and thus the chronology and provenance of detrital zircon revealed. The provenance analysis suggests that the detrital zircon in the sediments from the southern Okinawa Trough are sourced from the East China Sea shelf,Yangtze River and Lanyang River during the last 200 years, which means that the East China Sea shelf and Yangtze River dominated the provenance of the Late Quaternary sediments in the southern Okinawa Trough.

关 键 词：冲绳海槽 碎屑锆石 U-PB年代学 物源示踪 

分 类 号：P736[天文地球—海洋地质] P313[天文地球—海洋科学]