钱塘江河口区不同河段表层沉积物粒度特征及其对水动力的响应

doi:10.3969/j.issn.1000-5641.2016.06.020

摘要/Abstract

摘要：

钱塘江河口区为典型的喇叭形强潮型河口，受径流、潮流和长江沿岸流及其挟带泥沙的影响，沉积动力环境较复杂.本文通过对钱塘江枯水大潮潮区界（芦茨）以下（近口段、河口段和口外海滨段）表层沉积物的系统采样，分析了其沉积物类型和粒度组成在河口区不同河段和南、北岸的空间分布特征，并探讨了沉积动力环境.结果显示：钱塘江河口区表层沉积物以粉砂、粘土质粉砂为主；从上游至下游，三段沉积物粒度呈细-粗-细的空间变化特征，偏度相应表现为近对称-正偏、极正偏-正偏的特点，频率曲线峰型则具有多峰-高窄峰-矮窄峰的分布规律.其中，河口段受径流和潮流共同作用，在强潮环境下，表层沉积物粒度最粗，分选性最好.河口段和口外海滨段的南、北岸表层沉积物粒度也存在明显差异，反映北岸水动力相对南岸更强. Pejrup三角图分析表明，研究区水动力条件总体较强，其中河口段的水动力最强，不同河段沉积物粒度特征对水动力强度有很好的响应.

关键词: 沉积物, 粒度, 水动力, 河口, 钱塘江

Abstract:

The Qiantang River estuary is a typical funnel shaped, strong tidal estuary. It extends 274 kmlong from the tidal limit (at Luci) down to the mouth of Hangzhou Bay and possesses a complicated sedimentary hydraulic environment. This paper focuses on the grain size analysis of the surface sediments (68 samples in total)taken from the near bank underwater bottom. The grain size characteristics,types of sediments and their spatial distribution and the possible causes are discussed. Studies have shown that the sediments are mainly composed of silt and clayey silt. According to grain size composition,the estuary can be divided into three parts: the upper, middle and the lower. The sediments from both the upper and the lower parts are finer, poorer sorted than those from the middle part.The skewness parameter (SK) is featured with sub symmetric positive bias in the upper part, while very positively skewed positive bias in the lower part. From upstream to downstream the frequency curve shows different peak types of multipeak, high and narrow peak and low narrow peak. These differences in sediment composition and textures must have matched the different sedimentary hydrodynamic environment: the runoff in the upper part, alternative of runoff and tide in the middle, and mainly the tidal environment in the lower. As indicated by Pejrup triangulation, the hydrodynamic environment of this estuary is relatively strong, especially in the middle part, and the grain size characteristics show close relation to the hydrodynamic environment.

Key words: sediments, grain size, hydrodynamic force, estuary, the Qiantang River

刘朝; 师育新; 戴雪荣; 席雅娟;. 钱塘江河口区不同河段表层沉积物粒度特征及其对水动力的响应[J]. 华东师范大学学报(自然科学版), doi: 10.3969/j.issn.1000-5641.2016.06.020.

LIU Zhao, SHI Yu-xin, DAI Xue-rong, XI Ya-juan. Grain size characteristics of the surface sediments from the Qian Tang River Estuary and their implication for sedimentary hydrodynamics[J]. Journal of East China Normal University(Natural Sc, doi: 10.3969/j.issn.1000-5641.2016.06.020.

参考文献

[1] MASON C, FOLK R L.Differentiation of beach,dune and aeolian flat environments by size analysis,Mustang Island [J] . Journal of Sedimentary Petrology, 1958, 28:211-226.
[2] SPENCER D W.The interpretation of grain size distribution curves of clastic sediments [J] .Journal of Sedimentary Petrology, 1963, 33:180-190.
[3] POIZOT E, ANFUSO G, MEAR Y, et al. Confirmation of beach accretion by grainsize trend analysis: Camposoto beach, CAdiz, SW Spain [J] . Geo Marine Letters, 2013, 33(4):263-272.
[4] SADI H, SOUISSI R, ZARGOUNI F. Grain size characteristics of superficial sediments of the Gulf of Tunis (NE Tunisia) [J] . Arabian Journal of Geosciences, 2014, 7(8): 3365-3387.
[5] 贾建军,汪亚平,高抒，等. 江苏大丰潮滩推移质输运与粒度趋势信息解译[J] .科学通报,2006,50(22): 2546-2554.
[6] 尉建功,冯秀丽,林霖. 秦皇岛附近海域表层沉积物粒度分布特征及运移趋势分析[J] .中国海洋大学学报(自然科学版),2013(7):66-71.
[7] 李富祥,张春鹏,王路. 基于表层沉积物粒度特征的鸭绿江口沉积环境分析[J] .海洋科学,2014（5）:100-106.
[8] 郭艳霞,范代读,赵娟. 潮坪层序的粒度特征与沉积相划分以杭州湾庵东浅滩为例[J] .海洋地质动态,2004,20(5):9-14.
[9] 周晓静,高抒. 底质粒度信息的空间分异与代表性:以杭州湾舟山岛金山卫断面为例[J] .科学通报, 2004, 49(21):2228-2232.
[10] 陈卫跃. 潮滩泥沙输移及沉积动力环境以杭州湾北岸、长江口南岸部分潮滩为例[J] .海洋学报：中文版,1991(6):813-948.
[11] 陈沈良,杨世伦,吴瑞明. 杭州湾北岸潮滩沉积物粒度的时间变化及其沉积动力学意义[J] .海洋科学进展,2004,22(3):299-305.
[12] 王华强,高抒. 杭州湾北岸高潮滩沉积与沿岸物质输运趋势[J] .海洋地质与第四纪地质,2008,27(6):25-30.
[13] 刘阿成. 杭州湾口北部的表层沉积物粒度分布和动力沉积作用研究[J] .海洋通报,2004,21(1):49-56.
[14] 中国海湾志编纂委员会. 中国海湾志(第十四分册)[M] . 北京:海洋出版社, 1998.
[15] 谢东风, 潘存鸿, 曹颖,等. 近50a来杭州湾冲淤变化规律与机制研究[J] . 海洋学报:中文版, 2013(4):121-128.
[16] 赵雪华. 钱塘江河口及杭州湾自然特征和开发治理[J] . 海洋与海岸带开发, 1992(1):33-36.
[17] 余炯, 曹颖. 钱塘江河口治江缩窄后泥沙淤积成因分析[C] // 第十二届中国海岸工程学术讨论会论文集.2005.
[18] 尤爱菊,韩曾萃,何若英. 变化环境下的钱塘江河口潮位特性及其影响因素[J] .海洋学研究,2010,28(1):18-25.
[19] 成都地质学院陕北队. 沉积岩(物)粒度分析及其应用[M] . 北京:地质出版社, 1978.
[20] 杨世伦, 徐海根. 长兴、横沙两岛潮滩沉积物的粒度概率及其分析[J] . 海洋科学, 1994(1):60-63.
[21] WANG L, SARNTHEIN M, ERLENKEUSER H, et al. East Asian monsoon climate during the Late Pleistocene: high-resolution sediment records from the South China Sea [J] . Marine Geology, 1999, 156(1): 245-284.
[22] 乔淑卿, 石学法, 王国庆,等. 渤海底质沉积物粒度特征及输运趋势探讨 [J] . 海洋学报:中文版, 2010, 32(4):139-147.
[23] 黄龙, 张志珣, 耿威,等. 闽浙沿岸东部海域表层沉积物粒度特征及其沉积环境 [J] . 海洋地质与第四纪地质, 2014(6):161-169.
[24] 王艳杰, 唐红渠,姜仕军. 流溪河水库沉积物粒度的时空分布及其沉积动力学意义 [J] . 生态科学, 2015(3):1-6.
[25] 谢东风, 潘存鸿, 陆波,等. 基于实测资料的钱塘江涌潮水动力学特性研究 [J] . 水动力学研究与进展, 2012, 27(5):501-508.
[26] 王桂芝,周潮生,章绍英. 钱塘江潮区的主要水文特征 [J] .水文,1982(4):55-57.
[27] 祝丽丽,孙志林,黄赛花. 钱塘江河口弯道潮流场的数值模拟 [J] .浙江大学学报(理学版),2007(3):351-356.
[28] 谢东风, 高抒, 潘存鸿,等. 杭州湾沉积物宏观输运的数值模拟 [J] . 泥沙研究, 2012(3):51-56.
[29] 余炯, 曹颖. 治江缩窄后钱塘江河口泥沙淤积和成因探讨 [J] . 泥沙研究, 2006(1):17-24.
[30] PEJRUP M. The triangular diagram used for classification of estuarine sediments: a new approach [M] // DE BOER P L. TideInfluenced Sedimentary Environments and Facies. Dordrecht:Reidel, 1988: 289-300.
[31] 刘红,何青,王元叶,等. 长江口表层沉积物粒度时空分布特征 [J] .沉积学报,2007,25(3):445-455.