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对沙沟河一级阶地河漫滩ZJDZ剖面中360个样品的粒度,矿物的成分含量及pH值等沉积特征进行分析,并对关键层位进行了一共6个14C年代测定。结果表明:10.9～4.0kaB.P.期间沙沟河发生多次大规模洪水,10.9～7.0kaB.P.期间沙沟河发生20次左右大型洪水,洪水重现期为0.40ka,其中,10.9～9.0kaB.P.期间洪水的规模逐次增加,9.0～7.0kaB.P.期间洪水的规模有所减小;7.0～4.2kaB.P.期间至少有过4～5次大型洪水,洪水的重现期为0.71ka。洪水事件主要发生在比较湿润的气候背景下,高频率洪水事件的发生与气候频繁的干湿波动有关。
The sedimentary characteristics of 360 samples in the ZJDZ section of the Zhadou River floodplain profile were analyzed, and the sedimentary characteristics of the mineralogical compositions and pH values were analyzed. A total of 6 14C dating of the key beds were carried out. The results show that there are many large-scale floods in Shagou River from 10.9 to 4.0 kaB.P. In the period of 10.9-7.0 kaB.P., 20 large-scale floods occur in Shagou River with a flood recurrence period of 0.40 ka, of which 10.9 During the period of 9.0 ~ 7.0 kaB.P., the flood scale gradually increased from 9.0 to 7.0 kaB.P. At least 4 ~ 5 large floods occurred between 7.0 and 4.2 kaB.P., and the flood weight The current is 0.71ka. Flood events mainly occur in the relatively humid climate background. The occurrence of high-frequency flood events is related to frequent wet and dry climate fluctuations.