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根据西安北郊相家巷河漫滩沉积剖面中180个样品的颗粒分析和历史文献资料记载,研究了西安北郊相家巷漫滩沉积代表的洪水事件。研究表明:西安北郊相家巷剖面洪水沉积分层明显,对洪水的发生和短期降水量变化反映清楚。相家巷剖面洪水沉积厚度约为5.40m,可划分为28个层,指示发生了28次大小不同的洪水事件。剖面中的洪水沉积以中、粗砂和细砂为主,指示当时的洪水规模比近120年来关中渭河洪水明显大。这28次洪水事件发生时高漫滩上的洪水深度均大于2.2m,剖面中的第12、14、19～28层代表特大洪水事件。西安北郊相家巷洪水沉积代表的大规模洪水主要是由当年降水量的明显增加引起的。
According to the particle analysis and historical records of 180 samples in the sediment profile of the Xiangjiahe River floodplain in the northern suburbs of Xi’an, the flood events represented by the floodplain sediments of the Xiangjiaxiang suburb in the northern suburb of Xi’an were studied. The research shows that the flood sediment of the Xiangjia Alley section in the northern suburb of Xi’an is obviously stratified, and the occurrence of the flood and the changes of the short-term precipitation are clearly reflected. The flood sediment thickness at Xiangjia Lane section is about 5.40m, which can be divided into 28 layers, indicating that 28 flood events of different sizes have occurred. The flood sediments in the section are mainly medium, coarse sand and fine sand, indicating that the flood scale at that time was significantly larger than that of the Weihe River in Guanzhong in the past 120 years. The depth of flooding on high floodplains at these 28 flooding events was greater than 2.2 m and the 12th, 14th and 19th ~ 28th strata in the profile represented the catastrophic flood events. Large-scale floods, represented by flood sediments at Xiangjiaxiang in the northern suburb of Xi’an, were caused mainly by the significant increase in precipitation during the year.