汉江上游郧县庹家洲河段全新世古洪水研究  

Holocene Palaeoflood Hydrological Events of Upper Reaches of Hanjiang River in Tuojiazhou of Yunxian County

作　　者：白开霞[1] 查小春[1] 黄春长[1] 庞奖励[1] 顾洪亮[1] 赵英杰[1] 

机构地区：[1]陕西师范大学旅游与环境学院,陕西西安710062

出　　处：《水土保持通报》2013年第4期295-301,共7页Bulletin of Soil and Water Conservation

基　　金：国家自然科学基金重点项目"汉江上游(南水北调水源区)万年尺度古洪水水文学研究"(41030637);国家自然科学基金项目(41271108);国家社会科学基金重点项目(11AZS009);教育部博士点基金优先发展领域项目(20110202130002)

摘　　要：通过对汉江上游的实地调查，在湖北省郧县庹家洲段发现了含有4期古洪水滞流沉积层的典型全新世黄土古土壤剖面。结合野外观察和室内粒度、磁化率和烧失量等指标的测定，判定为典型的古洪水滞流沉积物（SWD），记录了汉江上游4期古洪水事件。通过地层对比、OSL断代等方法，确定这4期古洪水事件分别发生在12600-12400aB．P．，4200—4000aB．P．，3200-2800aB．P．和东汉时期1900-1800aB．P．。然后利用沉积学和水文学原理恢复了洪峰水位，并选择合适的水文参数，采用比降法水文模型推算出了这4期特大古洪水洪峰流量。同时。根据相同的方法，推算了剖面附近1983，2005和2010年洪痕对应的洪峰流量，与实测流量相比，误差在1．99％～4．21％，说明计算古洪水洪峰流量的水文参数选择与计算结果是合理的，而且古洪水洪峰流量计算结果也符合洪峰流量与流域面积关系。By field investigation in the upper reaches of the Hanjiang River, palaeoflood slack-water deposits （SWD） were found in loess profile on Tuojiazhou terrace land in Yunxian County of Hubei Province. Based on field observation, laboratory analysis, including loss on ignition, magnetic susceptibility, calcium carbonate and the grain-size distribution, four SWDs were identified as the most typical Holocene palaeoflood deposits in the Hanjiang River basin and which recorded four palaeofloods events. By using stratigraphic correlations and OSL dating, these four palaeofloods events were dated to 12 600 12 400 a B. P. , 4 200--4 000 a B. P. , 3 200-2 800 a B. P. and 1 900--1 800 a B.P. in Eastern Han Dynasty, respectively. Then according to the palaeoflood peak stages and reasonable hydraulic parameters, the peak discharges of four palaeofloods were calculated by using the slope-area method. To validate the calculation, the flood peak discharges of extraordinary floods in 1983, 2005 and 2010 were also reconstructed by using the same method and hydraulic parameters in the same cross-section. The error between the reconstructed and gauged discharges was 1.99%-4.21%. This indicated that the reconstructed palaeoflood peak discharges were reliable. And the recon- structed results of palaeoflood discharges were also consistent with the relationship between palaeoflood peak discharge and drainage area. This study prolonged the flood data sequence of Hanjiang River to a time-scale of over 10 000-years. More importantly, it provided significant data for flood control and hazard mitigation in the upper reaches of the Hanjiang River.

关 键 词：汉江上游 全新世 郧县 洪水事件 

分 类 号：TV122[水利工程—水文学及水资源]