Sediment production in large river basins throughout the Quarternary

晚新生代全球降温被认为与全球沉积速率的增加有关，这被解释为由于山脉侵蚀速率的增加。加强造山和气候变化都与侵蚀加剧和硅酸盐风化有关，这会消耗大气中的二氧化碳。然而，最近有人假设，在过去的1000万年里，全球大陆侵蚀的增加根本没有发生。相反，所观察到的全球沉积速率的增加被怀疑是由测量沉积的不同时间尺度引入的测量人工产物，以及沉积物记录的不完整保存。在这里，将通过分析保存的沉积记录和现代河流沉积物的宇宙成因核素浓度来测试晚第三纪以来侵蚀速率是否增加。埋藏的河流沉积物中的石英以原位产生的宇宙核素(10Be，26Al)的形式记录了河流整个盆地的剥蚀率。因此，剥蚀率，即侵蚀和风化的总和，可以在过去数百万年中重建。来自所有大陆(例如亚马逊、密西西比、恒河、刚果、墨累达令、多瑙河)的最大河流流域的沉积记录和现代沉积物样本，覆盖了33×106平方公里的地球S表面，将被测量其宇宙成因核素浓度，从而在几个时间片上获得具有统计意义的全球侵蚀覆盖范围。在粗时间分辨率下分析这一记录将提供平均的、长期的沉积物产生率，这将允许破译风化、侵蚀和大气二氧化碳水平之间的反馈。

Late‐Cenozoic global cooling has been suggested to be associated with a global increase in sedimentation rates, which is interpreted to be due to an increase in mountain erosion rates. Both enhanced mountain building and changes in climate are associated with increased erosion and silicate weathering that consumes atmospheric CO2. However, it has been hypothesized recently that an increase in global continental erosion in the last 10 million years did not take place at all. Rather, the observed worldwide increase in sedimentation rates is suspected to be a measurement artifact introduced by the different time scales over which sedimentation was measured, and the incomplete preservation of the sediment record.Here, it will be tested whether erosion rates have increased over the late Neogene by analyzing preserved sedimentary records and modern river sediment for their cosmogenic nuclide concentrations. Quartz in buried river sediment carries a memory of the rivers´ basin‐wide denudation rate, in the form of in situ‐produced cosmogenic nuclides (10Be, 26Al). Thus denudation rates, being the sum of erosion and weathering, can be reconstructed throughout the past several million years. Samples from sedimentary records and modern sediment from the largest river basins on all continents (e.g. the Amazon, Mississippi, Ganges, Congo, Murray‐Darling, Danube), covering > 33×106 km2 of Earth´s surface, will be measured for their cosmogenic nuclide concentrations, thereby obtaining a statistically significant coverage of global erosion in several time slices. Analyzing this record at coarse time resolution will provide average, long‐term sediment production rates that will allow to decipher the feedbacks between weathering, erosion and atmospheric CO2 levels.