中国基岩海湾潮流地貌模式及其沉积动力特征  

Tidal Geomorphology Patterns and Their Dynamic Sedimentary Characteristics in the Bedrock Bays of China

作　　者：边淑华[1] 夏东兴[1] 吕京福[1] 

机构地区：[1]国家海洋局第一海洋研究所

出　　处：《海洋科学进展》2003年第3期298-307,共10页Advances in Marine Science

基　　金：国家海洋局青年基金项目---沧口发育的发展和演变;青岛市科技局基金项目---胶州湾采砂与航道功能优化相关研究

摘　　要：对我国基岩海湾内的潮流沉积和地貌进行了系统研究。根据潮滩、潮流水道、潮流沙脊等地貌单元的组合特征,概括出3种潮流地貌模式:潮滩型、滩—槽型和滩—槽—脊型。通过各模式海湾环境特征的对比分析,设定紊动射流系数Rbjet做为判别潮流水道形成发育程度的水动力参数,发现潮流水道较为发育的滩—槽型和滩—槽—脊型海湾往往开敞度较小,纵深较长,而平均潮差较大,Rbjet大于45。潮流沙脊是区分滩—槽型和滩—槽—脊型潮流地貌模式的标志地貌,粗颗粒泥沙来源是其发育的必备条件:残留沉积、海岸侵蚀来沙丰富的海湾内潮流沙脊发育;河流来沙则可以改造形成小规模现代潮流脊;而靠近大河河口,细颗粒来源丰富的海湾则不利于潮流沙脊发育,湾内形成滩—槽型潮流沉积。In this paper, systematic studies on the tidal deposits and geomorphology in the bedrock bays of China are made, and three tidal geomorphology patterns, tidal flat pattern, tidal flat-channel pattern and tidal flat-channel-ridge pattern, are summarized based on the assemblage characteristics of geomorphological units such as tidal flat, tidal channel and tidal sand ridge. It is shown from the comparative analysis of the bay environment characteristics of different patterns that the turbulent jet coefficient R_(bjet) can be taken as the hydrodynamic parameter for judging the formation and development dagree of tidal channel, and the tidal flat-channel pattern and tidal flat-channel-ridge pattern with well-developed tidal channel are found to have a R_(bjet) value greater than 45. The tidal sand ridge is the indicator geomorphology for distinguishing the tidal flat-channel pattern from the tidal flat-channel-ridge pattern, and the coarse-grained sediment source is the essential condition for developing tidal sand ridge, namely, rich relict sediments and sediments from erosion coast are the sand source for developing sand ridge in the bay, the sediments from rivers can form small recent sand ridges, and the bay with rich fine-grained sediment source is unfavorable to the development of tidal sand ridge in the bay.

关 键 词：基岩海湾 潮流地貌模式 沉积动力特征 潮流沉积 

分 类 号：P737[天文地球—海洋地质]