Late Quaternary Sedimentary Environment and Landform Evolution in the Bengal Lowland.
Late Quaternary Sedimentary Environment and Landform Evolution in the Bengal Lowland.
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孟加拉低地晚第四纪沉积环境与地貌演化。
DOI：
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发表时间：
1987
期刊：
影响因子：
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通讯作者：
M. Umitsu
中科院分区：
文献类型：
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作者：
M. Umitsu
笔者在对沉积物分析的基础上，对近期沉积物进行了细分，探讨了孟加拉低地的地貌和沉积环境。近期沉积物可细分为5个部分，该地区的海平面曲线类似于所谓的“Sheperd曲线”，在约12,000至10,000yBP之间的某个时期内回归。在末次冰期的最大时期，流经孟加拉低地的河流在谷底沉积了砾石。此后，海平面上升至比现在水平低约 45 m，下部沉积了约 . 12,000 年前。在大约12,000年和10,000年BP期间，根据海平面的回归，对三角洲和洪泛平原表面进行了轻微的解剖。海退后，中段沉积以三角洲条件下的细粒沉积物为特征。上部构件在 10,000（或 8,000）yBP 和 6,000（5,000）yBP 期间沉积。大约之后。距今5000年，孟加拉低地广泛发育广阔的泥炭地或湿地。
The author subdivided the recent sediments and discussed the landforms and sedimentary envir onment in the Bengal Lowland based on the analysis of the sediments . The recent sediments are subdivided into five members , and the sealevel curve in the region is similar to so-called "Sheperd curve" with regression during a certain period between ca .12,000 and 10,000yBP. During the maximum epoch of the last glacial age , the rivers flowing in the Bengal Lowland deposited gravels on the valley floors . After the period, the sea level rose up to about 45 m below present level, and the lower member deposited by ca . 12,000yBP. During ca.12,000 and 10,000yBP, the delta and flood plain surface was slightly dissected according to the regression of the sealevel. After the regression, the middle member characterized by fine sediments in the deltaic condition deposited. The upper member deposited during 10,000 (or 8,000) yBP and 6,000 (5,000) yBP. After ca. 5,000yBP, broad peat land or wet land developed widely in the Bengal Lowland .