| 摘要: |
| 通过对废黄河河口水下三角洲海域水文、泥沙、沉积和地形的调查分析, 对组成水下三角洲-10—— -15m 以深的平坦海床、-5—— -10m 间的水下斜坡、-5m 以浅的近岸浅滩三个地貌单元的水动力特征以及在波流和潮流作用下底部泥沙冲刷率的横向分布进行计算分析,并建立了水下三角洲地形横向剖面地形的演变预测模式。结果表明, 在三角洲不同地貌单元内, 由于所处不同的水动力条件和底部泥沙特性, 出现了不同的侵蚀状态, 其中在-10—— -15m以深的平坦海床, 除了3m 以上的大浪外, 水动力作用以强劲的潮流冲刷为主, 目前已接近冲刷相对平衡的状态; 在-5—— -10m 间的水下斜坡, 受波浪和潮流的共同作用, 冲刷强度大, 地形剖面呈继续平行后退状态; - 5m 以浅的近岸浅滩, 潮流作用相对较弱, 以波浪对滩面的刷低为主, 水深线不断向岸方向移动、滩宽变窄; 0m 以上的潮间带滩地, 则波浪和潮流作用均较弱, 近岸高滩接近相对稳定状态, 有利于海岸线的工程防护。 |
| 关键词: 废黄河水下三角洲, 演变预测, 模式, 波浪, 潮流 |
| DOI： |
| 分类号: |
| 基金项目:国家自然科学基金资助项目, 49601001 号和40071014 号 |
附件 |
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| EVOLUTION PREDICTION OF THE ABANDONED YELLOW RIVER SUBMERGED DELTA UNDER WAVE AND CURRENT |
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YU Zhi-Ying1, ZHANG Guo-An1, JIN Liu1, BAO Si-Lin1, FAN She-Jun2
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1.State Key Laboratory of Estuarine & Coastal Research , East China Normal University;2.Old Dominion University
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| Abstract: |
| This paper presents a quantitative, dynamic model for simulating and predicting the evolution of the near shore muddy profile and the delta of the abandoned Yellow River. Based on the analysis of wave, current and sediment concentration data from field and laboratory, three different types of morphological zones, which are pro-delta shelf ( > 10m water depth with slope of < 1/1000) , delta front slope ( 5m to 10m isobath with slope of < 1/100) and subsided delta platform ( landward of the 5m is obath with slope of < 1/500) , have different characteristics and mechanisms of erosion. For the pro-delta shelf, strong tidal currents and large storms are the dominant forces for erosion, as the progressively exposed old muds that were deposited during the early stage of delta progradation has became relatively stable. For the former delta front slope, tidal currents and waves together contribute to the seabed erosion, although the tidal current is the dominant force during calm weather. For the delta-top platform, breaking waves are the dominant force for the erosion and profile evolution. The results show that the delta front slope and subsided delta platform are still in their younger stages of evolution, which is characterized by severe erosion. As the erosion continues, bed armoring and exposure of well consolidated old muds will cause the erosion rate to decrease and an equilibrium profile will reach finally. |
| Key words: Abandoned Yellow River submerged delta, Evolution prediction, Model, Wave, Tidal current |
