The long-term denudation rate of granitic regolith in Qinhuangdao, North China determined from the i

• 作 者: Lifeng Cui Congqiang Liu Sheng Xu Zhiqi Zhao Chenglong Tu Taoze Liu Hu Ding
• 机 构: State Key Laboratory of Environmental Geochemistry, Institute of Geochemistry, Chinese Academy of Sc
• 出 处: Chinese Science Bulletin
• 发表日期: 2014年34期
• 关键词: likely fitting averaged tectonic exponentially terrain implies quartz river exce

This study quantifies the surface denudation rate of granitic regolith via the application of the in situ cosmogenic26 Al and10Be depth profile in China. The concentration ranges of26 Al and10Be in the quartz along the*3-m granitic regolith profile in Qinhuangdao are(4.9–23.1) 9 105and(2.3–36.6) 9 104atoms/g, respectively. With the exception of the surface sample, both26 Al and10Be concentrations decrease exponentially with sample depth. The Chi-square best-fitting results revealed a total denudation rate of *9 m/Ma averaged over a 103–105a timescale, which is lower than the values observed in global granitic outcrops. Compared with global datasets, the flat terrain due to the lack of tectonic activities is most likely the dominant factor that controls the local denudation process.The surface sample offsets from the theoretical cosmogenic nuclide distribution implies that the denudation rate from river basin sediment could be overestimated because of the bioturbation in the surficial soil layer.

This study quantifies the surface denudation rate of granitic regolith via the application of the in situ cosmogenic 26 Al and 10Be depth profile in China. The concentration ranges of 26 Al and 10Be in the quartz along the * 3-m granitic regolith profile in Qinhuangdao are (4.9-23.1 ) 9 105 and (2.3-36.6) 9 104 atoms / g, respectively. With the exception of the surface sample, both 26 Al and 10 BE concentrations decrease exponentially with sample depth. The Chi-square best-fitting results revealed a total denudation rate of * 9 m Compared with global datasets, the flat terrain due to the lack of tectonic activities is most likely the dominant factor that controls the local denudation process. The surface sample offsets from the theoretical cosmogenic nuclide distribution implies that the denudation rate from river basin sedi could could be overestimated because of the bioturbation in the surfi cial soil layer.