Depocenter shift and en-echelon shoal development in the pre-Holocene incised valley of the Yangtze Delta, China
Depocenter shift and en-echelon shoal development in the pre-Holocene incised valley of the Yangtze Delta, China
复制标题
长江三角洲前全新世切谷沉积中心转移与阶梯状浅滩发育
DOI：
10.1016/j.margeo.2020.106212
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发表时间：
2020-08
期刊：
影响因子：
2.9
通讯作者：
Zhongyuan Chen
中科院分区：
文献类型：
--
作者：
Feng Jiang;Xiaoshuang Zhao;Jie Chen;Yan Liu;Qianli Sun;Jing Chen;Zhongyuan Chen
本研究根据现有文献中的关键信息和本研究收集的新岩心，建立了长江三角洲下切河谷的全新世沉积模型。揭示了下切谷独特的沉积作用过程和机制：1）前全新世下切谷在形成现今河口地貌中的重要作用，下切谷上形成了全新世漏斗状海湾;（2）全新世早-中期沉积中心的后退迁移与潮控桑迪滩的发育有关;全新世中晚期为河流-潮汐作用主导的海侵作用; 3）下切谷内以雁列桑迪滩为特征的沉积中心迁移模式，反映了全新世由海进沉积向海退沉积的阶段性迁移;（4）全新世以来，河谷内强烈的潮汐沉积作用控制了河口的右旋改道，而河谷外的科理奥利斯潮汐沉积作用则控制了河口的右旋改道。我们的研究结果进一步表明，在全新世山谷的沉积物的特点是有孔虫丰度向上增加。这是一个逆转的通常模式全新世海侵，表明一个独特的沉积环境中的山谷，可能是由于较高的浊度和保存不良造成的强大的潮流。
This study establishes a Holocene sedimentation model for the incised valley of the Yangtze Delta based on key information taken from existing literature and new cores collected for this study. Distinctive sedimentary processes and mechanisms operating in the incised valley were revealed: 1) the significant role of a pre-Holocene incised valley on which the Holocene funnel-shaped bay was established in forming the topography of the present river mouth; 2) the backstepping migration of the depocenter in association with tidally-dominated sandy shoals developed in the Early-Middle Holocene, followed by fluvially-tidally dominated progradation during the Mid-Late Holocene; 3) the model of depocenter shift characterized by en-echelon sandy shoals in the incised valley, revealing stepwise migration from transgressive to retrogressive sedimentation in the Holocene, and 4) the dextral diversion of the river mouth controlled by strong tidal sedimentation in the valley and the Coriolis-driven tidal sedimentation off the valley throughout the Holocene. Our results further show that the sediment in the Holocene valley was characterized by an upward increase in foraminiferal abundance. This is a reversal of the usual pattern to the Holocene marine transgression, indicating a unique depositional setting in the valley, presumably due to higher turbidity and poor preservation caused by strong tidal currents.
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DOI：
--
发表时间：
2004
期刊：
Marine Geology & Quaternary Geology
影响因子：
--
作者：
Wang Zhang-hua;M. Key
通讯作者：
Wang Zhang-hua;M. Key
影响因子：
2.9
作者：
Alastair J. H. Clement;I. Fuller;C. Sloss
通讯作者：
Alastair J. H. Clement;I. Fuller;C. Sloss
影响因子：
12.1
作者：
G. Vis;C. Kasse;D. Kroon;J. Vandenberghe;Simon J. A. Jung;S. Lebreiro;T. Rodrigues
通讯作者：
G. Vis;C. Kasse;D. Kroon;J. Vandenberghe;Simon J. A. Jung;S. Lebreiro;T. Rodrigues
影响因子：
4.4
作者：
M. Blaauw;J. Christen
通讯作者：
M. Blaauw;J. Christen
影响因子：
2.3
作者：
Zhanghua Wang;Qing Zhan;Haiyan Long;Y. Saito;Xiaoqin Gao;Xuxu Wu;Lin Li;Yanan Zhao
通讯作者：
Zhanghua Wang;Qing Zhan;Haiyan Long;Y. Saito;Xiaoqin Gao;Xuxu Wu;Lin Li;Yanan Zhao