Abstract
Chemical weathering contributes to the regulation of the global carbon cycle and biogeochemical cycles. Accordingly, the identification of the parameters that control weathering reactions and transport of weathering signals at the catchment scale is essential. The use of boron (B) isotopes have been shown to be a useful proxy in tracing weathering reactions due to large isotope fractionation during weathering processes. However, our knowledge of how boron isotopes record the weathering regime at the catchment scale and how that weathering signal is transported from source areas to the depositional environment remains limited. Here we characterize B isotope and major element behavior during chemical weathering and transport by analyzing the B isotopic (δ11B) and element compositions of riverine material (riverbank sands (<63 µm), clay fractions (<2 µm) extracted from sands, and dissolved load) along the course of the Murrumbidgee River (NSW, Australia), its upstream tributaries, and monolithologic subcatchments.
