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对伊洛河流域进行水文学和沉积学野外调查,在伊河龙门峡(LMX)地点发现典型的全新世黄土—古土壤剖面,根据野外沉积特征和磁化率、粒度分析判定该剖面夹有五层洪水滞流沉积层(SWD)。通过OSL测年和地层对比,确定该地层记录了四期五次特大洪水事件,分别发生在3100~3000 a BP、1800~1700 a BP、770~610 a BP和420~340 a BP,并结合史料等初步判断其中包含了AD 223和1761年历史洪水的沉积记录。这些古洪水事件与全新世气候恶化、转折和气候事件有明确的对应关系。采用古洪水水文学方法恢复洪峰水位,并采用比降—面积法计算出古洪水和历史洪水事件的洪峰流量介于14100~15800 m3/s。同时,根据实测获得1958年7月17日伊河龙门大洪水的洪峰水位和流量数据,采用相同参数和方法恢复其洪峰流量,误差仅有-3.6%,表明在该河段古洪水水文学重建所选参数和计算结果是可靠的。这些研究成果既证明季风气候区河流水文系统对全新世气候异常事件响应敏感,又为伊洛河流域水利、交通和防洪工程建设提供基础数据,具有重要的科学意义和实践价值。
A field survey of hydrology and sedimentology in the Yiluo River Basin was conducted. A typical section of the Holocene loess-paleosol was found at the LMX locality. According to the field sedimentary characteristics and magnetic susceptibility, Layer flood stagnant sediments (SWD). According to the OSL dating and stratigraphic correlation, it was confirmed that there were five major flood events of four stages recorded in this stratum, ranging from 3100 to 3000 a BP, 1800 to 1700 a BP, 770 to 610 a BP and 420 to 340 a BP, respectively The initial judgments of historical materials include the sedimentary records of the historical floods of AD 223 and 1761. These ancient flood events have a clear correspondence with the climatic deterioration, transition and climate events in the Holocene. The ancient flood hydrological method is used to recover the flood peak water level, and the peak-flow rate of the ancient flood and historical flood events is calculated using the slope-area method between 14100 and 15800 m3 / s. At the same time, according to the measured data of flood peak level and flow rate of the Great Flood of Longmen River on July 17, 1958, the same parameters and methods were used to recover the peak flow, the error was only -3.6%, indicating that in the ancient flood hydrological reconstruction The selected parameters and calculations are reliable. These findings not only prove that the monsoon climate system is sensitive to the Holocene climatic anomalies, but also provide basic data for water conservancy, traffic and flood control construction in the Yiluo River Basin. It is of important scientific and practical value.