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古洪水沉积物特征的研究对于识别古洪水沉积以及利用古洪水沉积物来恢复古洪水的水位,流量和发生规律都有十分重要的意义。在漆水河和湋河交汇的二级阶地上沉积了比较明显的古洪水沉积层。对该剖面进行磁化率、烧失量、碳酸钙、粒度指标的测定。并将古洪水沉积层与黄土堆积层进行对比发现:古洪水淤积层除了第三平流沉积层外,其它每个平流层指标数值都介于黄土堆积古土壤、马兰黄土之间。表明古洪水堆积层有较弱的成壤作用发生。这些指标揭示了古洪水堆积与黄土堆积之间的区别。
The research on the characteristics of ancient flood sediments is very important for identifying the ancient flood sediments and using the ancient flood sediments to restore the water level, flux and regularity of the ancient floods. The relatively ancient flooding sediments have been deposited on the secondary terraces where the Qiushui River meets the Bahe River. The profile was measured for susceptibility, loss on ignition, calcium carbonate, and particle size index. Comparing the paleo-flood sediment with the loess accumulation, we found that except for the third advection sediment, the values of every other stratospheric index are between the paleosol loess and Malan loess. This indicates that the paleo-flood accumulation layer has a weak pedogenic effect. These indicators reveal the difference between ancient flooding and loess accumulation.