【作者】 肖尚斌；

【导师】 李安春；

【作者基本信息】 中国科学院研究生院（海洋研究所） ， 海洋地质学， 2004， 博士

【摘要】 本论文旨在分析东海内陆架闽浙沿岸泥质沉积物的物质组成与来源，阐明其形成与演化历史，并从其形成的背景机制出发，初步揭示其中蕴藏的高分辨率东亚古季风记录和中国（特别是长江流域）古气候变化历史，并探讨二者的关系。 论文初步分析泥质沉积物的重矿物及粘土矿物组成，常量、微量和稀土元素的组成，指出了它们亲长江沉积物的特性；并用上述分析和元素之间的相关分析、非线性规划模型进行物源识别，判别出该泥质沉积区近2 ka的沉积物主要来源为长江，基本可以排除黄河的物源。 论文对位于该泥质沉积区北部的DD2孔和中部的PC-6孔进行了沉积环境分析，通过计算粒级-标准偏差获得了对沉积环境变化较为敏感的粒度组分，并就粒度组分与悬浮体进行对比，揭示出泥质沉积物为闽浙沿岸流以悬移方式搬运的产物。进一步的岩心和浅地层剖面分析表明，闽浙冬季沿岸流在约8 kaBP基本定型，而泥质沉积物的通量在近8 ka以来变化很大。 论文将闽浙沿岸流及其泥质沉积物与东亚古季风和中国（特别是长江流域）古气候联系起来，通过DD2孔，首次在陆架上建立了分辨率约为16 a的粒度序列和Rb/Sr序列，分别进行近2 ka以来高分辨率的东亚古季风和中国（特别是长江流域）古气候变化的研究；研究揭示出期间10次的东亚冬季风活动较强盛期，讨论了它们对古气候的影响。 进一步，通过建立PC-6孔近8 ka的粒度时间序列，首次较完整地揭示出东亚古季风近8 ka以来的活动强盛期，探讨了它们对古气候的影响；应用功率谱分析的方法，提取出同时段百年尺度和千年尺度的古季风周期，其中71 a周期为本文首次提出，并被认为是东亚季风活动最显著的基准周期之一。更多还原

【Abstract】 The composition, source, formation and evolutionof mud off Fujian-Zhejiang coast oftheinnershelf inthe East China Sea were analyzed. The research shows that the mud in thestudy area records the high-resolution evolution of East Asian Paleo-Monsoon andPaleoclimate in China , especially in the Yangtze River drainage area. The relationshipbetween them was discussed. The heavy minerals, clay minerals, major elements, trace elements and Rare EarthElements (REE) of the mud in the study area are analyzed. The results show that theyaresimilar to those of the Yangtze River. Based on above studies, and combing with thecorrelation analysis of different elements and material source analysis with nonlinearprogramming model, the author concluded that the sediment in the mud area mainlyderived from Yangtze River instead of YellowRiver inthe last 2 ka. Thesedimentary environment of core DD2 and PC-6 was discussed, which are locatedin the north and center of the study area respectively. The grainsize compositions sensitiveto the sedimentary environment were taken by the analysis ofgrain size grade vs. standarddeviation. Comparative researchbetween grainsize compositions and suspended matterswas done. All above analyses show that the mud derived from the Yangtze River istransported with suspension by Fujian-Zhejiang coastal current. The further analysis of coresediments and shallow profiles indicate that the Fujian-Zhejiang winter coastal current hasformed and kept stable since about 8 ka before, but mud flux has changed drastically in thisperiod. This thesis studied Fujian-Zhejiang coastal current and mud transported by it, and theirresponse to the East Asian Monsoon and Palaeoclimate in China, especially in the Yangtze<WP=6>　　　　　　　　　　　　　　　　　　　　　　　　　　　　　　　　　　　River drainage area. The grain size sequence with resolution of 16 a and Rb/Sr ratiosequence were reconstructed with core DD2 in the continental shelf for the first time.Furthermore, the East Asian Monsoon and Chinese paleoclimate were discussed with highresolution in recent 2 ka. The research shows that there were 10 strong East Asian WinterMonsoonduring the period. Based on the rebuilding of grain size sequence of Core PC-6 in recent 8 ka, the EastAsian Monsoon was revealed completely, and their influence on the Paleoclimate wasdiscussed. Using power spectral analysis, centennial and millennial-scale cycles of Paleo-monsoon were extracted. In the cycles, 71 a is the basic cycle of East Asian Monsoon.更多还原