In situ cosmogenic Be-10, Al-26, and Ne-21 dating in sediments from the Guizhou Plateau, southwest China |
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Landscape evolution is modulated by the regional tectonic uplift, climate change, and river dynamics. However, how to distinguish these mechanisms through the research of surface exhumation and fluvial incision remains controversial. In this study, cosmogenic Be-10, Al-26, and Ne-21 concentrations in quartz from cave deposits, modern river sediments, and bedrocks were measured to constrain the applicability of cosmogenic Ne-21 and discuss Quaternary landscape evolution history in the Guizhou Plateau, southeast China. Using the Al-26-Be-10 and Ne-21-Be-10 pairs to distinguish the cosmogenic Ne-21 concentration from the excess Ne-21, we found that the nucleogenic Ne-21 produced by the U and Th decay in quartz is significant in the samples although there is the possibility of inherited cosmogenic Ne-21. Combining with previous studies, we suggest that the precise approach for applying the cosmogenic Ne-21 could be reached by (1) estimating the contribution from nucleogenic Ne-21, (2) avoiding samples with complex burial histories to exclude inherited cosmogenic Ne-21, and (3) combining the Be-10-Al-26-Ne-21 nuclides method for the Quaternary samples. In addition, both pre-burial basin denudation rates and burial ages derived from the Al-26-Be-10 pair were used to determine the different timescale surface denudation rate and fluvial incision rate in relation to previous work. The consistency of the different timescales pre-burial basin denudation rate, Cl-36 surface denudation rate, and modern basin denudation rate indicates that the landscape-scale surface denudation has been likely stabilized since the Quaternary in the Guizhou Plateau area. The slightly higher river incision rates than the local surface denudation rate show that the river dynamics may not have reached a steady-state due to the regional tectonic uplift in the Guizhou Plateau.
Publication name |
SCIENCE CHINA-EARTH SCIENCES DOI10.1007/s11430-020-9744-6 Early AccessJUN 2021 |
Author(s) |
Yang, Ye; Liu, Yu; Ma, Yan; Xu, Sheng; Liu, Cong-Qiang; Wang, Shi-Jie; Stuart, Finlay M.; Fabel, Derek |
Corresponding author(s) |
XU Sheng sheng.xu@tju.edu.cn -Tianjin Univ, Sch Earth Syst Sci, Inst Surface Earth Syst Sci, Tianjin 300072, Peoples R China -Scottish Univ Environm Res Ctr, E Kilbride G75 0QF, Lanark, Scotland |
Author(s) from IGCAS |
WANG Shijie | View here for the details
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