Hydrothermal calcite-fluid REE partitioning experiments at 200 °C and saturated water vapor pressure

Carbonate complexation enhances hydrothermal transport of rare earth elements in alkaline fluids

“…The study of trace element behavior in hydrothermal fluids is challenging for a number of reasons, including low concentrations and potential backreactions upon quenching that lead to retrograde precipitation of new mineral phases, possibly obliterating the high-temperature information. Therefore, studies quantifying the solubility of REE minerals, their partitioning between different phases, or the mechanisms that enable their hydrothermal transport have been limited in terms of phases (e.g., the solubility of REECl 3 (s), REEF 3 (s), and, more recently, REEPO 4 (s)) and pH-P-T conditions (pH < 2 and T < 300 °C) 21,24,25,36,[40][41][42] .…”

Low oxygen levels with high redox heterogeneity in the late Ediacaran shallow ocean: Constraints from I/(Ca + Mg) and Ce/Ce* of the Dengying Formation, South China

“…Under oxic conditions, Ce is dominated by Ce (IV) phase and mostly adsorbed by Mn oxides, leading to a Ce depletion in ambient seawater (Alibo & Nozaki, 1999; de Baar et al, 2018; Pattan et al, 2005). REEs can substitute Ca 2+ and Mg 2+ during carbonate mineral precipitation (Perry & Gysi, 2020; Zhong & Mucci, 1995), and thus Ce anomaly is widely accepted as a recorder of seawater redox state and applied to ancient carbonates (Bellefroid et al, 2018; Hood & Wallace, 2015; Ling et al, 2013; Liu et al, 2021; Planavsky et al, 2010; Tang et al, 2016). In the modern stratified ocean, Ce anomaly shows vertical gradient associated with variation in dissolved O 2 content (Alibo & Nozaki, 1999; Bau et al, 1997; de Baar et al, 2018).…”

Differentiating between hydrothermal and diagenetic carbonate using rare earth element and yttrium (REE+Y) geochemistry: a case study from the Paleoproterozoic George Fisher massive sulfide Zn deposit, Mount Isa, Australia

“…The REE+Y partition strongly into carbonate minerals (e.g., Tanaka and Kawabe 2006;Voigt et al 2017;Perry and Gysi 2020), are enriched in crustal rocks (>chondrite), and occur only as trace components in fluids (<chondrite; Fig. 2a).…”

“…The REE+Y partition strongly into carbonate minerals (e.g., Tanaka and Kawabe 2006;Voigt et al 2017;Perry and Gysi 2020), are enriched in crustal rocks (>chondrite), and occur only as trace components in fluids (<chondrite; Michard and Albarède 1986;Michard 1989;James et al 1995;James and Elderfield 1996;Bau and Dulski 1999), modern oxygenated seawater data (light blue; James et al 1995;Alibo and Nozaki 1999;Haley et al 2004;Deng et al 2017), modern anoxic seawater data (dark blue; Schijf et al 1995;Bau et al 1997), and modern sediment pore water data (light purple; Haley et al 2004;Soyol-Erdene and Huh 2013;Deng et al 2017). b Redox equilibria for Eu 3+ /Eu 2+ , Yb 3+ /Yb 2+ , Fe 3+ /Fe 2+ , and SO 4 2-/H 2 S as a function of temperature and oxygen fugacity (after Bau and Möller 1992) compositions can be strongly affected even at low fluid-rock ratios (Michard and Albarède 1986;Bau 1991).…”

“…In low-temperature (e.g., marine or diagenetic) environments, in situ trace element analysis of carbonate minerals (e.g., laser ablation ICP-MS) has attracted increasing usage (e.g., Webb et al 2009;Himmler et al 2010). As the partitioning of rare-earth elements and yttrium (REE+Y) between fluids and carbonate minerals is well constrained (e.g., Morgan and Wandless 1980;Tanaka and Kawabe 2006;Perry and Gysi 2020) the fractionation of REE+Y can provide important constraints on physicochemical conditions (pH, temperature, ligand type, or fluid-rock interaction; e.g., Bau 1991;Bau and Möller 1992;Barker et al 2006). The REE+Y composition of carbonate can also vary significantly due to intrinsic processes such as closed-system effects and the carbonate growth rate (e.g., Kontak and Jackson 1995;Barker and Cox 2011).…”