Sedimentary Dynamics along the West Coast of Bohai Bay, China, during the Twentieth Century
Sedimentary Dynamics along the West Coast of Bohai Bay, China, during the Twentieth Century
复制标题
DOI：
10.2112/jcoastres-d-13-00073.1
复制
发表时间：
2014-03
期刊：
影响因子：
--
通讯作者：
Fu Wang;Hong Wang;Y. Zong;T. J. Andersen;Y. Pei;L. Tian;J. Li;Z. Shang
中科院分区：
文献类型：
--
作者：
Fu Wang;Hong Wang;Y. Zong;T. J. Andersen;Y. Pei;L. Tian;J. Li;Z. Shang
摘要王福；王宏华；宗勇；安徒生，T.J.；裴勇达；田林中；李建峰，尚志伟，2014。二十世纪渤海湾西岸沉积动力学研究，中国。为了研究渤海湾西岸沉积的最新变化，中国用Eijkelkamp取样器从天津近海滩涂采集了12个1-2m的原状沉积物短岩芯。根据沉积岩心测得的过剩或无支撑的~(210)Pb和~(137)Cs活度，建立了沉积序列的年代学，重建了潮滩的沉积史。结果揭示了天津沿岸沉积速率的时空变化，由此可以推断沉积动力学。确定了两个重要的时间边界。自1915年以来，随着滦河向北迁移，对海岸北段的泥沙供应减少。1958年前后，有几条河流修建了水坝。自1985年以来，天津港疏浚需求有所减少。这些行动导致包括海河在内的这些河流对沿海南北两部分的泥沙供应减少。一旦来自河流的泥沙供应减少，潮汐作用就会改变沉积物的特征，在本研究的大多数沉积物岩心中都记录到了向上细化的模式。这项研究强调了同时应用~(210)Pb和~(137)Cs测年方法的有效性。这些测年方法，再加上详细的沉积分析，可以提供海岸变化以及自然和人为变化原因的宝贵沉积证据。
ABSTRACT Wang, F.; Wang, H.; Zong, Y.; Andersen, T.J.; Pei, Y.D.; Tian, L.Z.; Li, J.F., and Shang, Z.W., 2014. Sedimentary dynamics along the west coast of Bohai Bay, China, during the twentieth century. To investigate the most recent changes in sedimentation along the west coast of Bohai Bay, China, we collected twelve 1–2 m short cores of undisturbed sediment from tidal flats off the city of Tianjin, using an Eijkelkamp corer. Based on the excess or unsupported 210Pb and 137Cs activities measured from the sediment cores, the chronology of the sediment sequences was established, from which the sedimentary history of the tidal flats was reconstructed. Results inform spatial and temporal variations in sedimentation rate along the Tianjin coast, from which sedimentary dynamics can be deduced. Two important time boundaries are identified. As the Luanhe River had migrated northwards since 1915, sediment supply to the northern section of the coast had reduced. Around 1958, several rivers were dammed. Since 1985, the need for dredging the Tianjin Port has decreased. These actions have resulted in a decline of sediment supply from these rivers, including Haihe, to both the northern and southern sectors of the coast. Once the supply of sediment from rivers was reduced, tidal processes acted to modify sediment characteristics, and an upward-fining pattern is recorded in the majority of sediment cores in this study. This study highlights the usefulness of applying both 210Pb and 137Cs dating methods. These dating methods, together with detailed sedimentary analysis, can provide valuable sedimentary evidence of coastal change and natural and human causes of change.