Natural Levees and Landform Evolutions in the Bengal Lowland
Natural Levees and Landform Evolutions in the Bengal Lowland
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孟加拉低地的自然堤坝和地貌演化
DOI：
10.4157/grj1984b.58.149
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发表时间：
1985
期刊：
影响因子：
--
通讯作者：
M. Umitsu
中科院分区：
文献类型：
--
作者：
M. Umitsu
模式。不连续天然堤防还细分为弧形、斑驳图案和槽坝上的天然堤防。这些类型的天然堤防的区域分布与洪水状况和根据各种文件和地图重建的河流转移有关。宽阔而隐蔽的天然堤防是古代恒河漂移形成的。到18世纪中叶，沿着恒河支流形成了宽阔而独特的天然堤坝。弧形和斑驳分布的天然堤坝是由雅鲁藏布江及其支流的干流在公元1830年形成的，当时雅鲁藏布江一直沿着Madhupur丛林以东流动。两条河流改道后，深水泛区形成了树枝状分布的天然堤防，中浅水泛区形成了曲流型天然堤防。天然堤坝上的航道沿两条河流形成了不规则分布的小型天然堤防
patterns. Discontinuous natural levees are also sub-classified into an arc-shaped, mottled pattern and natural levees on the channel bars. Regional distribution of these types of natural levees was considered in relation to the condition of floodings and to the river shiftings reconstructed from various documents and maps. Broad and obscure natural levees were formed according to the shiftings of the Ganges River in the ancient times. Broad and distinct natural levees were formed along the distributaries of the Ganges River by the middle of the eighteenth century. Arc shaped and mottled distributed natural levees were formed by the main flow of the Brahmaputra River and its distributaries by 1830 AD., during the period when the Brahmaputra River had been flowing along the east of the Madhupur Jungle. After the shiftings of the two rivers, natural levees distributed in a dendritic pattern and a meandering pattern have been formed in the deep flooding area and moderate and shallow flooding areas respectively. Natural levees on the channel bars have been formed along the two rivers and small natural levees of irregularly distributed