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自从上一次海平面上升以来,世界上的大部分河流都在广阔的大陆架上和河口区泄注沉积物。在大多数情况下,沉积物大都截留在这些地区,而不是沉积在这些河流出海方向的现代残留海底扇上。这一结论是以遥感资料、有关陆架和海底扇上现代沉积速率的文献资料、以及所研究的22条河流搬运的沉积物数量为依据提出来的。在陆架和河口区被填满以及沉积物能够绕过这些地区之前,这些海底扇始终都与其冲积源相隔开。填满这些陆架和河口区所需要的时间为:从恒河—布拉马普特拉河的2600—3400年到叶尼基—鄂毕河的1—1.2百万年。对大多数水系来说,在陆架和河口区被沉积物填满之前,海平面将会改变。
Since the last sea level rise, most of the world’s rivers have drained sediments over vast continental shelf and estuarine areas. In most cases, most of the sediments are trapped in these areas rather than deposited on the modern residual sea fan in the direction of the rivers going to the sea. This conclusion is based on remote sensing data, literature on modern deposition rates on the shelf and submarine fan, and the amount of sediment transported by the 22 rivers studied. These submarine fans are always separated from their alluvial source until the shelf and estuarine zones are filled and sediments can bypass these areas. The time required to fill these shelf and estuarine areas ranges from 2600-3400 years on the Ganges-Brahmaputra to 1-1.2 million years on the Yeni-Ob river. For most systems, the sea level will change until the shelf and estuaries are filled with sediments.