引用本文: | 易朝路,刘惠芳,N.Rose,倪乐意,刘克新.长江中游泥沙与洪水来源的网湖沉积记录.湖泊科学,2003,15(Z1):235-242. DOI:10.18307/2003.sup29 |
| YI Chaolu,LIU Huifang,Neil L. Rose,NI Leyi,LIU Kexing.Sources of Bedload and Flooding in Wanghu Lake:Evidence from the Lake Sediment Record. J. Lake Sci.2003,15(Z1):235-242. DOI:10.18307/2003.sup29 |
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长江中游泥沙与洪水来源的网湖沉积记录 |
易朝路1,2, 刘惠芳3, N.Rose4, 倪乐意5, 刘克新6
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1.中国科学院青藏高原研究所, 北京 100092;2.南京大学城市与资源学系, 南京 210093;3.中国地质大学(武汉)测试中心, 武汉 430073;4.英国伦敦大学学院地理系环境演变研究中心;5.中国科学院水生生物研究所淡水生态技术国家重点实验室, 武汉 430072;6.北京大学重离子物理研究所, 北京 100864
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摘要: |
在长江中游湖北省东部网湖湖心的采取柱状沉积物,用210Pb+137Cs方法测定表层的沉积速率.制作连续切片,选取深度7烈-88lmm的层型沉积较完整的一段样品,用显微镜量测浅色层和暗色层的厚度,采用电子探针确定层的地球化学成份,并由此计算了纹层的主要矿物组成.认为纹层主要是由于在洪水季节长江带来的浅色泥沙与在枯水季节富水河带来的含暗色矿物泥沙交替沉积形成的.泥沙主要来源于夏季长江倒灌入湖的洪水,部分来自长江支流富水河;冬季枯水季节,泥沙基本来源于长江支流富水河. |
关键词: 湖泊层型沉积 泥沙来源 长江干流和支流 地球化学元素 纹层厚度 |
DOI:10.18307/2003.sup29 |
分类号: |
基金项目:国家自然科学基金(40271016和4997108)联合资助 |
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Sources of Bedload and Flooding in Wanghu Lake:Evidence from the Lake Sediment Record |
YI Chaolu1,2, LIU Huifang3, Neil L. Rose4, NI Leyi5, LIU Kexing6
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1.Institute of the Tibetan Plateau, Chinese Academy of Sciences, Beijing 100092, P. R. China;2.Department of Geography, Nanjing University, Nanjing 210093, P. R. China, China;3.Testing Center, China University of Geosciences at Wuhan 430073, P. R. China;4.Environmental Change Research Centre, University College London, 26 Bedford Way, London, WC1H OAP, UK;5.Donghu Experimental Station of Lcdce Ecosystems, State Key Laboratory for Freshwater Ecology and Biotechnology of China, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan 430071, P. R. China;6.Institute of Heavy Ion Physics, Peking University, Beijing 100871, P. R. China
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Abstract: |
A sediment core was collected from the centre of Wanghu Lake, in the middle reaches of the Yangtze River. The core was dated using a combination of 210Pb, 137Cs; spheroidal carbonaceous particle (SCP) techniques were applicated. The laminated section between 723 and 881mm, dated to the 18th century, was selected for detailed study. The thickness of the laminae was measured using a reflecting microscope whilst geochemistry was determined by an electron probe. The thickness of the dark layers was found to be positively correlated with titanium concentrations and the minerals rutile and ilmenite, and negatively correlated with potassium concentrations and the mineral hydromica. The thickness of the light layers was found to be negatively correlated with the concentrations of potassium, titanium and ferric oxide and the minerals rutile and ilmenite. It is concluded that the dark layers were deposited from the Fushui River, a tributary of the Yangtze River, under periods of normal flow whilst the light layers were deposited from the Fushui and the Yangtze River itself during flood periods. |
Key words: Laminated sediments Yangtze River sediment geochemistry flood sources |
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