百年来黄河三角洲东北部毗邻海域沉积记录演化及其影响因素

发布时间：2017-12-28 07:38

本文关键词：百年来黄河三角洲东北部毗邻海域沉积记录演化及其影响因素　出处：《海洋地质与第四纪地质》2016年04期 　论文类型：期刊论文

【摘要】：通过对黄河三角洲东北部毗邻海域采集的多个沉积物岩心,开展系统的沉积物粒度、有机碳氮及其同位素特征的分析,结合210Pb年代测定,探讨研究区近百年来高分辨率的沉积记录及其变化的主要因素。研究表明:岩心O3、M2和B63处于相对稳定的沉积环境中,沉积物的粒度分布都呈阶段性变化但表现出差异性,O3和M2自1976年以来沉积物粒度出现粗化,而距离现行河口较近的B63则变细之后粒度粗化,在沉积物的上段C/N和δ13C的变化都反映了陆源有机质输入的增加。黄河1976年改道使三角洲北部和东部海域的沉积环境发生改变,O3和M2受再悬浮泥沙的影响粒度变粗,废弃三角洲叶瓣再悬浮泥沙对研究区的供给量增加,导致O3和M2接受更多陆源有机质的供给。而B63受到更多较细粒黄河入海泥沙影响,粒度变细,陆源有机质输入也增加。黄河入海水沙的阶段性递减和调水调沙工程导致输运至研究区的细粒物质减少,使岩心B63沉积物上段层位的粒度变粗。
[Abstract]:Through a plurality of sediment cores from the northeast of the Yellow River Delta and adjacent waters acquisition, analysis of organic carbon and nitrogen isotopes and carry out grain system, combined with the 210Pb dating of the study area of nearly a hundred years of high-resolution sedimentary record and the changes of the main factors. Research shows that: O3, M2 and B63 in the core sedimentary environment is relatively stable, the sediment grain size distribution in phase change but show the difference between O3 and M2 since 1976, grain size became coarse, and the distance closer to the estuarine B63 thin after coarse granularity, changes in sediment C/N and 13C are the upper delta reflects an increase of terrigenous organic matter input. The diversion of the Yellow River in 1976 changed the depositional environment of the northern and eastern waters of the delta. The size of O3 and M2 affected by re suspended sediment became coarser. The supply of suspended sediment to the study area increased, resulting in O3 and M2 receiving more terrestrial organic matter. B63 is influenced by more finer particles in the Yellow River, finer grain size and increase of land source organic matter input. The gradual decline of water and sediment and water and sediment control projects in the Yellow River lead to the reduction of fine particles transported to the study area and the coarser granularity of the upper layer of B63 core.
【作者单位】：中国海洋大学海底科学和探测技术教育部重点实验室;中国海洋大学海洋地球科学学院;国家海洋局第三海洋研究所;中国地质调查局青岛海洋地质研究所;黄河水文水资源勘测局;
【基金】：国家自然科学基金项目(41476069)
【分类号】：P736.21
【正文快照】： 河流是联系陆地和海洋的重要纽带,输入到海洋的物质主要来自于陆地上河流所携带的沉积物,全球河流每年输送到海洋的沉积物通量约为183亿t[1]。渤海是半封闭的陆架边缘浅海,周边河流输入的陆源物质是渤海最主要的沉积物来源,这些河流包括黄河、海河、滦河、辽河等,其中黄河的入

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