长江中游洪水沉积特征与标志初步研究

洪水记录是研究洪水规律的重要依据。通过对1998、1999、2002年长江中游洪水沉积物的系统观察、对比和研究,结果表明,长江中游洪泛沉积在沉积体形状、沉积结构和沉积物成分等方面,具有与正常河道沉积明显不同的特点,可为古洪水事件确定提供可能和依据。根据沉积环境的不同,长江中游洪泛沉积大致可分为3种类型:溃口洪水事件的沉积、滨岸带的洪水沉积和洪水漫滩沉积。进而对各种类型的沉积学特征进行了分析、归纳和总结,初步建立了其识别标志。

Flood sedimental characteristic and its mark on the middle reaches of Yangtze River

Flood record is a foundation studying flood happen law. In order to establish the identification mark of flood sediment in the flooded area at the middle reaches of the Yangtze River, We study the flood sediments in 1998, 1999 and 2002. The results show that the flood sediments are obviously different from the normal channel deposits on sediment body shape, sedimental texture and sediment composition in the middle reaches of Yangtze River. The results of study can provide the feasibility and basis for the history flood events identification in the field.The sedimentary characters of the flooded deposits on crevasse splay sedimentary, flooded flat and shore side are studied and summarized in the paper.