摘要: |
利用多波束、侧扫声纳以及单道地震资料对胶州湾湾口潮流作用下形成的典型海底沙波地貌的平面形态、剖面特征和分布特点进行了分析研究。根据实测的水文资料计算了不同潮流流速下沙波的瞬时移动速度,推测了直脊型沙波和新月型沙波的形成]化过程:区内新月型沙波在西向优势流的作用下大约以50m/a的速度向西迁移,直脊型沙波则在两端方向不一致的优势流长期作用下,发生逆时针旋转,同时在往复流的作用下以一个平衡位置左右摆动;就地貌形态而言,新月型沙波是不稳定的,直脊型沙波达到相对平衡状态。 |
关键词: 胶州湾湾口 海底沙波 多波束数据 潮流 迁移速度 |
DOI: |
分类号: |
基金项目:国家自然科学基金资助项目,40576033号 |
附件 |
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TOPOGRAPHY FEATURE AND MIGRATION OF SUBMARINE SAND WAVES IN JIAOZHOY BAY MOUTH |
ZHAO Yue-Xia1,2, LIU Bao-Hua2, LI Xi-Shuang2, WU Jing-Long2, SU Tian-Yun1,2
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1.Ocean University of China, Qingdao, 266003;2.First Institute of Oceanography, State Oceanography Administration, Qingdao, 266061
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Abstract: |
Based on multibeam bathymetric data, side-scan data and seismic profiles, morphology and migration of submarine sand waves in the Jiaozhou Bay mouth are studied. In morphology, two types of sand waves are recognized: straight crest type and crescentic type. The study shows that the distribution of sand waves is controlled by tidal current. The straight crest sand waves are located on the slope north of the sea route where the current velocity of westward flood tide is counteract to that of eastward ebb tide. The straight crest sand waves wiggle and rotate counterclockwise under the control of dominant current in different directions at two terminals. The crescentic sand waves are formed by westward dominant current to the north of the straight crest ones. Migration rate of these two kinds of sand waves at different current speeds are calculated using Rubin formula. The crescentic sand waves move westward at about 50m/a. The straight crest ones are relatively stable in a long period of time, but can migrate back and forth for several decimeters in a tidal cycle. The migration rate indicates that the submarine sand waves are instable. Special caution must be taken in submarine engineering, especially laying cables or pipes. |
Key words: Jiaozhou Bay mouth, Submarine sand wave, Multibeam bathymetric data, Tidal current, Migration rate |