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中科院边缘海地质重点实验室海洋沉积与古环境课题组陈木宏研究员领导的团队，通过对南海东北部柱状沉积物样品进行高分辨率的综合分析，探讨了全新世以来黑潮入侵的历史演化及其对南海北部沉积环境变迁的影响。该研究成果2013年发表在The Holocene上，题目“Influence of the Kuroshio Current intrusion on Holocene environmental transformation in the South China Sea” 以南海东北部位于黑潮入侵路径上一重力岩心05E306（见图1）为研究对象，进行了包括浮游有孔虫、粘土矿物和地球化学元素等多方面的系统分析。结果表明，该岩心处沉积速率呈现出逐渐减缓的趋势，约6千年最快（1000 cm/ka），6.0~4.6千年较快（~65 cm/ka）和4.6千年以来最慢（~24 cm/ka）。与黑潮影响有密切关系的浮游有孔虫常见种Pulleniatina obliquiloculata、Neogloboquadrina dutertrei和Globorotalia menardii显示了黑潮入侵在距今6.0千年、4.6千年和2.7千年经历重要变化（见图2）。而研究区的沉积环境，也类似地依次在6.0千年、4.1千年好3.0千年发生了转变。研究岩心上述沉积记录的突然变化与全新世热带太平洋地区的ENSO记录在时间上是同时的，这意味着黑潮入侵历史及其对南海北部沉积环境的影响与来自低纬度地区的热带因素密切相关。 该项研究工作得到了国家重点基础研究发展计划项目（973项目）、国家自然科学基金和中国科学院知识创新工程青年人才领域前沿等项目的资助。 Abstract: Numerous studies have been conducted on the evolutionary history of the Kuroshio Current (KC) and other extensions. However, the history of the KC intrusion into the South China Sea (SCS) through the Luzon Strait has been little studied. Here we trace the Holocene developmental history of the KC intrusion and its impact on environmental transformation in the northern SCS. This study involved a comprehensive analysis of planktonic foraminifera, clay minerals and geochemical elements of core 05E306 sediments from the northeastern SCS. AMS 14C dates indicated that the sedimentation rate at the core site was most rapid (>1000 cm/ka) before ~6.0 ka, relatively rapid (~65 cm/ka) between 6.0 and 4.6 ka and slow (~24 cm/ka) since 4.6 ka. The Pulleniatina minimum event (PME) occurred between 4.6 and 2.7 ka, together with high percentages of Neogloboquadrina dutertrei and Globorotalia menardii.Planktonic foraminifera indicated that the KC intrusion experienced three significant changes at 6.0, 4.6 and 2.7 ka in turn. Depositional environments, including input of terrigenous materials and development of biogenic materials, similarly underwent three important transformations at 6.0, 4.1 and 3.0 ka, respectively. Abrupt changes in sedimentary records at the study core are contemporary with records from the tropical Pacific during the Holocene. This indicates that development of the KC intrusion and its impact on depositional environments in the SCS can be correlated with tropical factors from the low-latitude oceans.
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