Sedimentary Characteristics of theModern Tidal Flat of Jiuduansha Shoal in Changjiang Estuary
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摘要: 根据2003年对长江河口九段沙潮间带和潮上带的现场调查和室内对沉积构造、粒度分布、矿物组成、沉积速率等的分析,对九段沙现代潮滩的沉积特征进行了研究。研究表明九段沙潮间带以小型交错层理为主,波痕发育,粒度主要为细砂至粗粉砂;潮上带主要为水平层理,粒度主要为中细粉砂。潮间带和潮上带的沉积矿物组成非常接近。沉积速率以潮间带低而潮上带高为特点。Abstract: Based on the field surveys in 2003 and laboratory analysis of the samples which taken from Jiuduansha Shoal, the sedimentary structure, grain size distribution, assemblages of the clayminerals and the sedimentation rates are studied aswell. The sedimentation rate is determined by 210 Pb method, and the results show that the sedimentation rate of the sup ratidal zone ismuch higher than that in the inter-tidal zone. The intertidal zone of the Jiuduansha shoal are mainly micro-wave and cross bedding, and sediments are dust-color fine sand and coarse silt, this zone is affected by the wave and tidal currents, some special sedimentary structure formed, and boulder clay, ripple and erosion ridge existed, these structure formed under wave processes. Sup ratidal zone are mainly horizontal bedding, and sediments are mainly middle-fine silt, because of dominant species are Phramites australis and Scirpus mariqueter on the supratidal zone, here is the lower energy sedimentary environment, and sedimentary structure are horizontal bedding,and mean size is between 5.0-27.0Φ. Clayminerals are similar between inter-tidal zone and sup ratidal zone, claymin-eralsmainly are illite, montmorillonite, kaolinite and chlorite, but they content on sup ratidal and intertidal zone are different. The sedimentation rate on the intertidal zone are 0.735cm / a, and on the supratidal zone, the sedimentation rate are 3.342 cm / a, higher than that on the intertidal zone.
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Key words:
- Yangtze River /
- Jiuduansha shoal /
- modern tidal flat /
- sedimentary characteristics
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[1] 1 黄胜,韩乃斌,钟秀娟. 长江口拦门沙淤积分析[A].北京:水利学会,1980.1-10.
2 黄胜. 长江河口演变特征[J].泥沙研究,1986,(04):1-12.
3 钱宁,张仁,周志德. 河床演变学[M].北京:科学出版社,1987.268-270.
4 李九发,沈焕庭,徐海根. 长江河口底沙运动规律[J].海洋与湖沼,1995,(02):138-145.
5 Li Jiufa,Zhang Chen. Sediment resuspension and implications for turbidity maximum in the Changjiang estuary[J].Marine Geology,1998.117-124.
6 李九发,何青,张琛. 长江河口拦门沙河床淤积和泥沙再悬浮过程[J].海洋与湖沼,2000,(01):101-109.
7 潘定安,孙介民. 长江口拦门沙地区的泥沙运动规律[J].海洋与湖沼,1996,(03):279-286.
8 潘定安,沈焕庭,茅志昌. 长江口浑浊带的形成机理与特点[J].海洋学报(中文版),1999,(04):62-69.
9 张志忠,阮文杰,蒋国俊. 长江口动力絮凝沉降与拦门沙淤积的关系[J].海洋与湖沼,1995,(06):632-638.
10 沈焕庭,朱慧芳,茅志昌. 长江河口环流及其对悬沙输移的影响[J].海洋与湖沼,1986,(01):26-35.
11 沈焕庭,李九发,金元欢. 河口涨潮槽的演变及治理[J].海洋与湖沼,1995,(01):85-89.
12 沈焕庭,潘定安. 长江河口最大浑浊带[M].北京:海洋出版社,2001.28-51.
13 沈金山,朱珍妹,张新琴. 长江口南槽拦门沙的成因和演变[J].海洋与湖沼,1983,(06):582-590.
14 陈吉余,恽才兴,徐海根,董永发. 两千年来长江河口的发育模式[J].海洋学报(中文版),1979,(01):103-111.
15 Chen J Y,Zhu S Z,Lü Q R,Zhou Y Q,He S L. Descriptions of the morphology and sedimentary structures of the river mouth bar in the Changjiang estuary[M].New York:Academic Press,1982.667-675.
16 Chen J Y,Zhu H F,Dong Y F,Sun J M. Development of the Changjiang estuary and its submerged delta[J].Continental Sheff res,1985.47-56.
17 陈吉余. 长江口拦门沙及水下三角洲的动力沉积和演变[J].长江流域资源与环境,1995,(04):348-355.
18 Chen Jiyu,Li Daoji,Chen Banglin,Hu Fangxi,Zhu Huifang,Liu Cangzi. The processes of dynamic sedimentation in the Changjiang estuary[J].Journal of Sedimentary Research,1999.129-140.
19 刘宝珺. 沉积岩石学[M].北京:地质出版社,1980.307-320.
20 杨世伦,贺松林,谢文辉. 长江口九段沙的形成演变及其与南北槽发育的关系[J].海洋工程,1998,(04):55-65.
21 王永红. 长江河口涨潮槽的形成机理与动力沉积特征[D].上海:华东师范大学,2003.
22 刘国贤,杨松林,周义华. 用210Pb法测定长江口区的沉积速率[J].海洋地质与第四纪地质,1984,(01):113-116. -
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