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How post-burial terrestrial in situ cosmogenic nuclides (TCN) production is build-up in slow burial condition remains uncertain. In this study, we dated high fluvial terrace sediments that overlain by loess with a slow deposition rate that is based on the assumption of steady accumulation rate via 26Al/10Be burial dating method. For sample in deep and rapid buried condition prior to slow overlying, post-burial production shows low component (4–6%) in measured concentration. However, post-burial production occupied 39–79% of measured 26Al and 10Be concentrations, which suggests approximately 0.2–0.3 Ma underestimation in simple burial dating mode if post-burial production is neglected. Corrected by post-burial production, we yielded burial ages of two top terraces (ca. 1.7–2.5 Ma and 1.5 Ma, respectively) below the Tangxian planation surface along the Jinshan Gorge of the Yellow River, implying that the Jinshan Gorge initially incised at ca. 1.7–2.5 Ma, corresponding well to regional tectonic activities, such as extension in the Fenwei Graben, accelerative uplift of the Tangxian planation surface, vigorous dissection of North China, and significant tectonic deformation in northeastern Tibetan Plateau. The slow burial mode is probably a potential method for plateau paleo-elevation estimation taking advantage of height sensitivity of TCN production rate if overlying loess magnetostratigraphic age is known. |
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