| 引用本文: | 曹希强,郑祥民,周立旻,杜耘,远藤邦彦.洪湖沉积物的磁性特征及其环境意义.湖泊科学,2004,16(3):227-232. DOI:10.18307/2004.0306 |
| CAO Xiqiang,ZHENG Xiangmin,ZHOU Limin,DU Yun,Kunihiko Endo.Paleoenvironmental Implication of Magnetic Measurements on Sediments Core from Honghu Lake. J. Lake Sci.2004,16(3):227-232. DOI:10.18307/2004.0306 |
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| 摘要: |
| 以洪湖沉积物为研究对象, 通过对Hh01-2(B)孔岩芯磁参数的测量发现在岩芯所代表的时间段内洪湖沉积物磁化率呈现了明显的四个主阶段变化;频率磁化率变化与磁化率变化具有较好的相关性, 亚铁磁性矿物的变化主导了沉积物磁化率的变化.同时结合年代、孢粉分析以及参考相关历史记载资料, 发现磁化率高值段对应湖水动力强、湖面较宽、气候较湿润, 而磁化率低值段对应湖水动力弱、湖面较小、气候偏干旱.从而得出了洪湖沉积物磁参数曲线波峰和波谷分别对应洪湖在历史上曾经历了扩张和收缩、气候温湿和冷干的旋回. |
| 关键词: 洪湖 湖泊沉积物 磁性测量 环境演变 |
| DOI：10.18307/2004.0306 |
| 分类号: |
| 基金项目:国家自然科学基金项目(40131020, 40372135);上海市重点学科计划项目资助. |
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| Paleoenvironmental Implication of Magnetic Measurements on Sediments Core from Honghu Lake |
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CAO Xiqiang1, ZHENG Xiangmin1, ZHOU Limin1, DU Yun2, Kunihiko Endo3
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1.Key Lab. of Geographic Information Science of MOE, East China Normal University, Shanghai 200062, P.R.China;2.Institute of Geodesy and Geophysics, Chinese Academy of Sciences. Wuhan 430077, P.R.China;3.Department of Geosystem Sciences, Nihon University. Tokyo, Japan
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| Abstract: |
| Honghu Lake is a shallow lake in the Jianghan Plain.The sediment core Hh01-2(B) from Aug., 2001 was selected for analysis.Based on magnetic measurements of the core, we can find that the changes of magnetic susceptibility appear as four obvious main stages since 900a B.P.The changes between frequency dependent magnetic susceptibility (χfd%)and magnetic susceptibility (χ) of the core have close relations, whereas the contents of finer-grain ferrimagnetic minerals play a leading role in the changes of magnetic susceptibility.Meanwhile, according to 210Pb dating and spore-pollen analysis and referring to the relevant historical materials, we get the following conclusion: the sections with higher magnetic susceptibility correspond to the periods with stronger hydrodynamics, wider surface of the lake, and relatively moist climate;otherwise, those with lower magnetic susceptibility correspond to the periods with softer hydrodynamics, narrower surface of the lake, and relatively droughty climate. |
| Key words: Honghu Lake lake sediments magnetic measurement environmental change |
