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Chinese Journal of Geochemistry

, Volume 22, Issue 2, pp 156–163 | Cite as

The paleo-environmental significance of Sr and Ca contained in acid-soluble fraction of plateau loess deposits in Xining Basin

  • Tan Hongbing
  • Ma Haizhou
  • Lu Huayu
  • Zhang Xiying
  • Wei Haizhen
Article
  • 30 Downloads

Abstract

The Xining Basin, located on northeastern Qinghai-Xizang Plateau, is adjacent to the Qaidam Basin and Gobi-desert. Therefore, thick, integrated deposits of loess or paleo-sol sequence were well developed. As is well known, there is much paleo-environmental information recorded in loess and paleo-sol. So if we deal with paleo-environmental index from different angles, especially from loess geochemistry, some important and detailed paleo-environmental evolutional information will be acquired. Based on this, the authors determined the contents of Sr and Ca contained in acid-soluble fraction from the bottom to the top of the Panzishan section. This section was obtained through making a well about 17 m in depth, including S1 paleo-sol that was developed during the last interglacial period. According to the results, it is found that variations in contents of Sr and Ca are well correlated with conversion of loess and paleo-sol. In loess deposits, the contents of Sr and Ca are higher than those in paleo-sol deposits. It is known that loess was deposited under cold-dry climate conditions and paleo-sol was developed during warm-humid climate episodes. It is concluded that due to their mobile behaviors, under cold-dry climate conditions, Sr and Ca are stagnant during weak weathering, but under warm-humid climate conditions, Sr and Ca are easily leached and transported in aqueous solution. Therefore, they can be utilized as indicators of climate changes. Moreover, variations in contents of Sr and Ca are more sensitive than susceptibility. The mobile behaviors of Sr and Ca contained in acid-soluble fraction can serve as a new quantitative index to evaluate paleo-environmental changes on the plateau.

Key words

Xining basin loess deposit geochemical index concentrations of Sr and CaO 

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References

  1. Chen Jun, An Zhisheng, and J. Head, 1999, Variation of Rb/Sr ratios in the loess-paleo-sol sequences of central China during the last 130000 years and their implications for monsoon paleoclimatology [J]: Quaternary Research, v. 51, p. 215–219.CrossRefGoogle Scholar
  2. Chen Jun, An Zhisheng, Wang Yongjin et al., 1998, Distribution of Rb/Sr and paleomonsoon variability during the last 800000 years in Luochuan Loess section, Shaanxi, China [J]: Science in China, v. 28, n. 6, p. 498–504 (in Chinese).Google Scholar
  3. Chen Jun, Ji Junfeng, Qiu Gang, Lu Huayu, and Zhu Hongbing, 1997, Geochemical studies on the intensities of chemical weathering in the Luochuan Loess-paleo-sol sequence, Shaanxi, China [J]: Science in China (Series D), v. 27, n. 6, p. 531–536 (in Chinese).Google Scholar
  4. Chen Jun, Qiu Gang, Lu Huayu et al., 1996, Geochemical evidence on summer monsoon variation recorded by concentration of Rb and Sr element on the Loess Plateau over the last 130000 years [J]: Chinese Science Bulletin, v. 41, n. 21, p. 1963–1966 (in Chinese).Google Scholar
  5. Chen Jun, Wang Hongtao, and Lu Huayu, 1996, Behaviours of REE and other trace elements during pedological weathering-evidence from chemical leaching of loess and paleo-sol from the Luochuan section in Shaanxi, China [J]: Acta Geologica Sinica, v. 70, n. 1, p. 61–72 (in Chinese with English abstract).Google Scholar
  6. Chen Jun, Wang Yongjin, Chen Yang et al., 2001, Rb and Sr geochemical characterization of the Chinese loess and its implications for paleomonsoon climate [J]: Acta Geologica Sinica, v. 75, n. 2, p. 259–266 (in Chinese with English abstract).Google Scholar
  7. Chen Jun, Wang Yongjin, Ji Junfeng et al., 1999, The variation of Rb/Sr and its climate strata significance in Luochuan Loess section, Shaanxi, China [J]: Quaternary Research, v. 19, n. 4, p. 350–356 (in Chinese with English abstract).Google Scholar
  8. Gallet, S, B-M. Jahn, and M. Torii, 1996, Geochemical characterization of the Luochuan loess-paleo-sol sequence, China, and paleoclimatic implications [J]: Chem. Geol., v. 133, p. 67–88.CrossRefGoogle Scholar
  9. Hao Qingzhen and Guo Zhengtang, 2001, Quantitative studies on weathering intensity of Loess-paleo-sol sequences and East Asian summer monsoon variations over the past 1.2 Ma [J]: Science in China (Series D), v. 31, n. 6, p. 520–528 (in Chinese).Google Scholar
  10. Li Zhen and Nie Shuren, 1999, Xining loess deposition and its mental sources, China [J]: Earth Science-Journal of China University of Geosciences, v. 24, n. 6, p. 581–584 (in Chinese with English abstract).Google Scholar
  11. Liu Dongsheng et al., 1997, Quaternary environment [M]: Beijing, Science Press, p. 66–67 (in Chinese).Google Scholar
  12. Lu Huayu, Ma Haizhou, Tan Hongbing et al., 2001, Plateau monsoon variations during the past 0.13 Ma indicated by loess deposit at Xining, Northeast Qinghai, China [J]: Quaternary Research, v. 21, n. 5, p. 416–423 (in Chinese with English abstract).Google Scholar
  13. Mou Baolei, 1999, Element geochemistry [M]: Beijing, Peking University Press, p. 174–176 (in Chinese).Google Scholar
  14. Verosub, K. L., P. Fine, M. J. Singer et al., 1994, Pedogenesis and paleoclimate: Interpretation of the magnetic susceptibility record of Chinese loess-paleo-sol sequences [J]: Reply Geology, v. 22, p. 859–860.Google Scholar
  15. Yang Zhongfang, Zhu Li, and Chen Yuelong, 1999, Modern environment geochemistry [M]: Beijing, Geological Publishing House, p. 143–144 (in Chinese).Google Scholar

Copyright information

© Institute of Geochemistry, Chinese Academy of Sciences 2003

Authors and Affiliations

  • Tan Hongbing
    • 1
  • Ma Haizhou
    • 1
  • Lu Huayu
    • 2
  • Zhang Xiying
    • 1
  • Wei Haizhen
    • 1
  1. 1.Qinghai Institute of Salt LakesChinese Academy of SciencesXiningChina
  2. 2.Institute of Earth EnvironmentChinese Academy of SciencesXi’anChina

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