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对CSH1岩心全样沉积物样品进行元素地球化学分析,揭示了过去88ka冲绳海槽北部沉积物成分、水动力条件及陆源碎屑物质源区风化历史。冲绳海槽北部碎屑沉积物母岩主要以长英质为主,在MIS 1期沉积物存在大量火山源物质。过去88ka,沉积物源区风化程度较弱,但是自冰消期以来有逐渐增强的趋势。沉积物Zr/Nb比值表明在MIS 1期和MIS 5.1期水动力较为强烈,这与黑潮增强的时间一致,可能是指示黑潮强度的一个指标。冲绳海槽北部陆坡沉积物陆源碎屑贡献在低海平面时期显著增加,而在MIS 1和MIS 5.1期生源贡献显著增加。冲绳海槽北部沉积物成分变化明显受到黑潮和入海径流的调节,实际上受海平面和东亚季风的制约。
Elemental geochemical analysis of the CSH1 core sediment samples reveals the sediment composition, hydrodynamic conditions and the weathering history of the terrigenous source rocks in the northern Okinawa Trough during the last 88 ka. The clastic sedimentary rocks in the northern Okinawa Trough mainly dominated by quartzites, and a large amount of volcanic source material existed in MIS 1 sediments. In the past 88 ka, the source areas of the sediments were weathered less, but the tendency was gradually increasing since the ice was removed. The Zr / Nb ratio of sediments shows that the hydrodynamic force is more intense in MIS 1 and MIS 5.1, which is consistent with the time of enhanced Kuroshio, which may be an indicator of Kuroshio intensity. Contributions of terrestrial clastic sediments to continental slope sediments in the northern Okinawa Trough increased significantly during the low sea level, but significantly increased in the MIS 1 and MIS 5.1 periods. Changes in sediment composition in the northern Okinawa Trough are clearly regulated by the Kuroshio and runoff, which are actually constrained by sea level and the East Asian monsoon.