A model for oblique accretion on the South China Sea margin; Red River (Song Hong) sediment transport into Qiongdongnan Basin since Upper Miocene
A model for oblique accretion on the South China Sea margin; Red River (Song Hong) sediment transport into Qiongdongnan Basin since Upper Miocene
复制标题
南海边缘斜向增生模型；
DOI：
10.1016/j.margeo.2019.106001
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发表时间：
2019-10
期刊：
影响因子：
2.9
通讯作者：
Hua Wang
中科院分区：
文献类型：
--
作者：
Rui Zhao;Si Chen;Cornel Olariu;Ronald Steel;Jinyu Zhang;Hua Wang
琼东南盆地位于南海西北缘，晚中新世以来沉积在大陆边缘的不对称陆棚斜坡斜坡，其成因尚不明确，可能是新近纪至现代海平面变化期间世界上研究最多的泥质陆棚中第一例斜向沉积物输运和扩散。根据二维地震资料计算了建立陆棚斜坡斜坡所需的古沉积通量，结果比海南岛近端集水区的古沉积通量大3 ~ 17倍。这种大的不匹配性表明，琼东南盆地陆架边缘的沉积物不仅来自海南岛，而且更可能来自一个更大的水系。琼东南陆架边缘折流带西部向南迁移的幅度较大（数十km），东部的陆架边缘折流带则较弱（1-2 km），表明琼东南陆架棱柱体高度不对称，是由以西部为中心的大量沉积物供应造成的，而红河（宋洪）很可能是沉积物供应的驱动力。海南岛陆架边缘沉积物的细粒岩性特征，特别是中新世末以来的细粒岩性特征，表明它们主要来自红河，并由陆架流从北部湾向东南方向搬运。我们提出了一个模型，不对称的陆架斜坡加积的泥丰富的货架中，一个显着的一部分，沉积物棱柱体体积斜向分散在整个下沉的货架作为流体泥浆在高位海平面。这里提出的模型描述了倾斜建设的陆棚斜坡在泥丰富的系统在多个海平面周期的沉积物扩散和沉积中心的变化。这种长期（~ 107年）的横向不对称加积模式与世界各地其他源-汇沉积系统中的倾斜沉积物输运形成对比。
Located on the northwestern margin of the South China Sea, the origin of asymmetrical shelf-slope clinoforms accumulated on the continental margin of the Qiongdongnan Basin since the late Miocene is ambiguous and it likely is the first case of oblique sediment transport and dispersal among the most studied mud-rich shelves of the world during Neogene to Recent sea-level changes. We calculate the paleo-sediment flux required to build the shelf-slope clinoforms based on 2-D seismic data, and the results are 3 to 17 time larger than the estimated paleo-sediment discharge from the proximal catchment area of Hainan Island. This large mismatch suggests that sediments on the shelf-edge of Qiongdongnan Basin were not only from Hainan Island but more likely from a larger drainage system. The strong (tens km) southward migration of the western portion of the Qiongdongnan shelf-edge break compared to the weak (1–2 km) shelf-edge progradation in the eastern portion, suggests that the Qiongdongnan shelf prism is highly asymmetric and is caused by a large sediment supply centered to the west, with most likely the Red River (Song Hong) as the sediment supply driver. The fine-grained lithology of the studied shelf margin sediments off Hainan Island, especially since the end Miocene, suggests that they were derived mainly from the Red River and were transported southeastward from the Gulf of Tonkin by shelf currents. We propose a model for asymmetric shelf-slope accretion of mud-rich shelves in which a significant part of the sediment-prism volume was obliquely dispersed across the subsiding shelf as fluid mud during highstand sea-levels. The model presented here describes oblique construction of shelf-slope clinoforms in a mud-rich system in response to variations in sediment dispersal and depocenter during multiple sea-level cycles. This model of long-term (~107years), lateral asymmetric accretion contrasts with oblique sediment transport in other source-to-sink sedimentary systems around the world.
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DOI：
10.1016/0302-3524(74)90016-4
发表时间：
1974-07
期刊：
Estuarine and Coastal Marine Science
影响因子：
--
作者：
B. Gallenne
通讯作者：
B. Gallenne
影响因子：
2.9
作者：
Yang Peng;R. Steel;C. Olariu
通讯作者：
Yang Peng;R. Steel;C. Olariu
DOI：
--
发表时间：
2008
期刊：
Journal of Tropical Oceanography
影响因子：
--
作者：
Sun Zhen;C. Key
通讯作者：
Sun Zhen;C. Key
影响因子：
1.4
作者：
Liu Xiaofeng;Zhang Daojun;Xiu Chun
通讯作者：
Xiu Chun
影响因子：
2.9
作者：
J. Warrick
通讯作者：
J. Warrick