88ka以来冲绳海槽北部物源及沉积通量演化  

SEDIMENT PROVENANCE AND FLUXES IN THE NORTHERN OKINAWA TROUGH DURING THE LAST 88 KA

作　　者：朱爱美[1,2,3] 石学法[3,4] 邹建军[3,4] 吴永华[3,4] 张辉[3] 白亚之[3] 

机构地区：[1]中国科学院地球化学研究所矿床地球化学国家重点实验室,贵阳550002 [2]中国科学院大学,北京100049 [3]国家海洋局第一海洋研究所海洋沉积与环境地质国家海洋局重点实验室,青岛266061 [4]青岛国家海洋科学技术实验室海洋地质过程与环境功能实验室,青岛266061

出　　处：《海洋地质与第四纪地质》2015年第5期1-8,共8页Marine Geology & Quaternary Geology

基　　金：中央级公益性科研院所基本科研业务费专项资金资助项目(GY0213G23);国家自然科学基金项目(41206059;41420104005和40710069004);亚洲大陆边缘"源-汇"过程与陆海相互作用(GASI-GEOGE-03)

摘　　要：通过对CSH1岩心131个沉积物样品中的稀土元素进行分析,恢复了冲绳海槽北部88ka以来碎屑物质来源及古环境的演化历史。结果显示,88ka以来稀土元素含量发生了剧烈的波动,范围为111~171.3μg/g（均值为130.9μg/g）,高值出现在MIS2期,低值主要出现在MIS1期。在MIS4期存在显著的Ce负异常,这与底层水体通风减弱相关。物源分析表明,8ka以来冲绳海槽北部沉积物存在火山碎屑的贡献,MIS2—MIS5a期以陆源碎屑为主。在MIS2期与MIS4期及末次冰消期早期和晚期沉积物来源存在显著的差异。海平面与东亚夏季风是控制冲绳海槽北部陆源碎屑物质累积的主要因子。The history of terrigenous detritus accumulation and paleoenvironment since the last 88 ka was reconstructed using the results of rare earth elements（REEs）from 131 samples from the Northern Okinawa Trough.The results show that the contents of∑REEs vary between 111~171.3μg/g with an average value of 130.9μg/g.The apex of∑REEs occurs in MIS 2,while the low values exist in Holocene.Negative Cerium anomaly exists in MIS 4,which is mainly controlled by the ventilation of deep water.Provenance analysis suggests that the sediment components are dominated by terrigenous detritus during MIS 2and MIS 5a,while the contribution of volcanic detritus significantly increases over the last 8ka.There exists provenance difference between MIS 2-MIS4,and the early and late last deglacial periods.Both sea level and East Asian Summer Monsoon are the main controlling factors for terrigenous detritus accumulation in the northern Okinawa Trough.

关 键 词：稀土元素 沉积物源 Ce负异常 沉积通量演化 冲绳海槽北部 

分 类 号：P736.4[天文地球—海洋地质]