Elevated weathering rates in the Rocky Mountains during the Early Eocene Climatic Optimum

摘要: Silicate weathering reactions remove carbon dioxide from the atmosphere and store it in carbonate minerals. During high atmospheric conditions of Early Eocene Climatic Optimum, rates chemical weathering, physical erosion denudation western USA were equivalent to highest recorded non-glacial Quaternary. silicate minerals, is incorporated into minerals buried. As rate thought increase response increasing CO2 concentrations, this represents an important negative feedback mechanism1. Quaternary records reflect a narrow range pCO2 (180–300 p.p.m.v.)2; therefore, extent has been difficult predict for concentrations CO2. However, levels up 1,125 p.p.m.v. have suggested Optimum (52 50 million years ago)3,4,5. Here, we combine 40Ar/39Ar ages6 measured volumes river-derived sediments sodium-bearing evaporites determine Green River Basin, United State America, during Optimum7. We find 420±79 t km2 yr−1 62.5±21.9 t km2 yr−1. The calculated 175±30 m Myr−1 rival documented crystalline bedrock8. suggest that elevated epoch led enhanced dissolution rates9, thus increased production loose rock material higher denudation.