Unusually heavy stable Mo isotope signatures of the Ottawa River: Causes and implications for global riverine Mo fluxes

Iron and Molybdenum Isotope Application for Tracing Industrial Contamination in a Highly Polluted River

“…The variations in Mo isotopes in different natural reservoirs due to anthropogenic pollution have also been observed in the literature. The Mo isotopic fractionation can be utilized to discern whether the natural water reservoirs, such as rivers and oceans, have been affected by anthropogenic pollution [34][35][36]. Lastly, Mo isotopic differentiations could also offer the further investigation of anthropogenic contamination in various nature environments such as sediments, soils, and aerosols [37][38][39].…”

Diagenesis Decreasing the Mo Isotopic Composition in Estuarine Systems: Implications for Constraining Its Riverine Input to Ocean

“…Critically, these paleoredox investigations presuppose the consistent transfer of continental Mo isotopic compositions through riverine pathways for Mo to the oceans (Anbar, 2004;Arnold et al, 2004;Kendall et al, 2017;Siebert et al, 2003), with rivers recognized as primary conduits for Mo to the oceans. However, subsequent research has indicated that average isotopic composition of river water is characteristically enriched in heavier isotopes compared to those of catchment bedrock (e.g., Archer & Vance, 2008;Horan et al, 2020;King et al, 2018;J.-H. Liu et al, 2020;Neubert et al, 2011;O'Sullivan et al, 2021;Pearce et al, 2010;Revels et al, 2021;Voegelin et al, 2012;Zeng et al, 2019). This enrichment in heavy isotopes in river water is ascribed to the chemical weathering of continental rocks, which often involves incongruent dissolution and preferential adsorption of isotopically light Mo on Fe-Mn oxide and organic phases (e.g., Archer & Vance, 2008;King et al, 2016;J.-H. Liu et al, 2020;Neubert et al, 2011;Siebert et al, 2015;Voegelin et al, 2012;.…”

“…However, subsequent research has indicated that average isotopic composition of river water is characteristically enriched in heavier isotopes compared to those of catchment bedrock (e.g., Archer & Vance, 2008; Horan et al., 2020; King et al., 2018; J.‐H. Liu et al., 2020; Neubert et al., 2011; O’Sullivan et al., 2021; Pearce et al., 2010; Revels et al., 2021; Voegelin et al., 2012; Z. B. Wang et al., 2015; Z. Wang et al., 2018; Zeng et al., 2019).…”