Exploring Quaternary paleolake evolution and climate change in the western Qaidam Basin based on the bulk carbonate geochemistry of lake sediments
Exploring Quaternary paleolake evolution and climate change in the western Qaidam Basin based on the bulk carbonate geochemistry of lake sediments
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基于湖泊沉积物本体碳酸盐地球化学探讨柴达木盆地西部第四纪古湖泊演化与气候变化
DOI：
10.1016/j.palaeo.2016.01.021
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发表时间：
2016-03
期刊：
影响因子：
--
通讯作者：
Shaopeng Gao
中科院分区：
文献类型：
--
作者：
Yibo Yang;Xiaomin Fang;Andreas Koutsodendris;Chengcheng Ye;Rongsheng Yang;Weilin Zhang;Xiaomin Liu;Shaopeng Gao
本文研究了柴达木盆地西部(青藏高原)SG-1岩心沉积的稀醋酸可溶部分中常量元素和微量元素的含量，以探索应用整体碳酸盐分析追踪古湖泊演化和气候变化的潜力。SG-1岩心沉积物被认为非常适合于探索块状碳酸盐地球化学的古环境意义，因为岩心中的大多数碳酸盐都是自生的。在对稀醋酸渗滤液的元素组成进行主成分分析的基础上，提取了4个特征明显的主成分，对总方差的贡献率约为80%。第一个也是最重要的一个组分与高的正负载量的Mn、P、Y、Sc和稀土元素(REE)有关；第二个组分的特征是高的正负载量的钙、锶和铀；第三个组分的特征是高负载量的镁、锂、硼；第四个组分与相对较高的Fe、V和Cr的正负载量有关。在考虑了这些元素组合在酸浸过程中的地球化学行为后，我们得出结论，这四个组分分别包含指示流域气候条件、碳酸盐降水、湖泊水盐度和氧化铁含量的信息。利用分量分数重建的流域气候变化和古湖泊演化与由其他独立代理记录重建的结果相当，表明了约2.7亿Ma以来湖泊萎缩和气候干燥的长期趋势，其中约2.5亿Ma、约1.8亿Ma、约1.2亿Ma和约0.6亿Ma发生了突然的干旱事件。我们的结果表明，湖泊碳酸盐比预期承载了更多关于流域气候和湖泊演化的信息，稀释的醋酸渗滤液中某些元素的赋存状态，特别是微量元素的存在，并不是唯一且必然与碳酸盐矿物有关。
This study focuses on the concentration of major and trace elements in the diluted acetic acid-soluble fraction of SG-1 core lacustrine sediments from the western Qaidam Basin (Tibetan Plateau) in order to explore the potential of applying bulk carbonate analysis to tracing paleolake evolution and climate change. The SG-1 core sediments are considered highly suited to the exploration of the paleoenvironmental significance of bulk carbonate geochemistry, because most carbonates in the core are authigenic in origin. Based on a principal component analysis of the elemental composition of diluted acetic acid leachate, four major components with distinct characteristics have been extracted, accounting for ~ 80% of the total variance. The first and most important component is associated with a high positive loading of Mn, P, Y, Sc and rare earth elements (REE); the second component is characterized by a high positive loading of Ca, Sr, and U; the third component displays a high negative loading of Mg, Li, and B; and the fourth component is associated with a relatively high positive loading of Fe, V and Cr. After considering the geochemical behavior of these element assemblies during acid leaching, we have concluded that these four components contain information indicative of watershed climate conditions, carbonate precipitation, lake water salinity and iron oxide content, respectively. Reconstructions of watershed climate change and paleolake evolution using the component scores are comparable to those reconstructed from other independent proxy records, indicating a long-term trend of lake shrinkage and climatic drying since ~ 2.7 Ma with abrupt drying events at ~ 2.5 Ma, ~ 1.8 Ma, ~ 1.2 Ma and ~ 0.6 Ma. Our results suggest that lake carbonates bear more information about watershed climate and lake evolution than expected, and that occurrences of some elements, in particular trace elements, in the diluted acetic acid leachate are not solely and necessarily linked to carbonate minerals.
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影响因子：
12.1
作者：
J. Warren
通讯作者：
J. Warren
青藏高原东北部碳酸盐岩组成及其对河流地球化学的影响
影响因子：
3.9
作者：
Qingquan Meng;Chengcheng Ye;Rongsheng Yang;Xiaoming Liu
通讯作者：
Xiaoming Liu
DOI：
10.1007/1-4020-2504-1_04
发表时间：
2006
期刊：
--
影响因子：
--
作者：
M. Leng;A. Lamb;T. Heaton;J. Marshall;B. Wolfe;Matthew D. Jones;J. Holmes;C. Arrowsmith
通讯作者：
M. Leng;A. Lamb;T. Heaton;J. Marshall;B. Wolfe;Matthew D. Jones;J. Holmes;C. Arrowsmith
影响因子：
1.9
作者：
R. Reyment;J. C. Davis
通讯作者：
R. Reyment;J. C. Davis
DOI：
10.1016/0031-0182(96)00002-8
发表时间：
1996-09
期刊：
Palaeogeography, Palaeoclimatology, Palaeoecology
影响因子：
--
作者：
B. Haskell;D. Engstrom;S. Fritz
通讯作者：
B. Haskell;D. Engstrom;S. Fritz