| 引用本文: | 王夏青,黄春长,庞奖励,查小春,周亚利,王恒松,顾洪亮,周芳,魏海燕.黄河中游北洛河宜君段全新世特大洪水及其气候背景研究.湖泊科学,2011,23(6):910-918. DOI:10.18307/2011.0613 |
| WANG Xiaqing,HUANG Chunchang,PANG Jiangli,ZHA Xiaochun,ZHOU Yali,WANG Hengsong,Gu Hongliang,ZHOU Fang,WEI Haiyan.Holocene palaeo-floods and climatic changes in the Yijun reaches of the Beiluohe River, middle reaches of the Yellow River. J. Lake Sci.2011,23(6):910-918. DOI:10.18307/2011.0613 |
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| 摘要: |
| 通过对黄河中游北洛河的野外考察, 在宜君基岩峡谷全新世风成黄土-土壤剖面中发现三层古洪水滞流沉积物(SWD).野外观察和室内实验分析, 证明它们是北洛河特大洪水悬移质泥沙在高水位滞流环境下的沉积物.这些古洪水滞流沉积层夹在全新世中期古土壤之内, 其每一层记录了一期特大洪水事件.利用古水文学方法恢复了古洪水洪峰水位和流量, 确定三期古洪水的洪峰流量介于13600-14100m3/s之间.这就将北洛河中游洪水数据序列延长到万年尺度, 为更加精确地建立洪峰流量-频率关系奠定了基础.这些结果对北洛河流域水利工程建设和防洪减灾提供了可靠依据.根据土壤地层和气候地层对比, 结合OSL测年数据, 确定这三期古洪水的发生年代为8000-7800 aBP(SWD1), 6000-5000aBP(SWD2)和4200-4000 aBP(SWD3).它们与全新世大暖期三个气候突变事件密切相关, 是气候不稳定状态下, 区域水文系统极端性变化的重要表现.这就为深入理解全球变化对于半干旱地区气候水文系统的影响提供了新的证据。 |
| 关键词: 北洛河 黄河中游 古洪水 滞流沉积物 全新世大暖期 气候突变 |
| DOI：10.18307/2011.0613 |
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| 基金项目:国家自然科学基金重点项目(41030637,40771018);中央高校基本科研业务费专项基金项目(GK200901007,GK200902020)联合资助 |
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| Holocene palaeo-floods and climatic changes in the Yijun reaches of the Beiluohe River, middle reaches of the Yellow River |
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WANG Xiaqing, HUANG Chunchang, PANG Jiangli, ZHA Xiaochun, ZHOU Yali, WANG Hengsong, Gu Hongliang, ZHOU Fang, WEI Haiyan
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College of Tourism and Environmental Sciences, Shanxi Normal University, Xi'an 710062, P.R.China
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| Abstract: |
| Holocene palaeo-flood slackwater deposits (SWD) were found in Yijun reaches of the Beiluohe River in the middle rea-ches of the Yellow River.They were identified by sedimentary criteria during fieldwork initially.A set of three beds of palaeo-flood SWD was interbedded in the Holocene loess-soil sequence within the cliff riverbanks.Each of the SWD represents one individual palaeo-flood event.The analytical results of grain-size distribution and magnetic susceptibility indicate that these SWD beds were deposited from the suspended sediment load in the floodwater.According to climatic and stratigraphic correlation with the OSL da-ted Holocene profiles in the region, these palaeo-flood events occurred during 8000-7800 aBP (SWD1), 6000-5000 aBP (SWD2) and 4200-4000 aBP(SWD3), respectively.The palaeo-flood peak discharges were calculated by hydrological models and estimated to between 13600 and 14100 m3/s.The archives of flood data were therefore extended to a time-scale of over 10000 years.A more reliable flood peak discharge and frequency relationship was established accurately.These results are very important in hydraulic engineering and mitigating flood hazard in Beiluohe River basin.These palaeo-floods are well correlated to the abrupt climatic events occurred during the mid-Holocene Climatic Optimum.They provide solid evidence for investigating the social im-pacts of per-historical floods on the decline of the Neolithic civilizations in China' s monsoon regions. |
| Key words: Beiluohe River mildle reaches of the Yellow River palaeo-flood slackwater deposits Holocene Climatic Optimum abrupt change |
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