Experimental Constraints on Clumped Isotope Fractionation During BaCO₃ Precipitation

Abstract

Carbonate clumped isotope (Δ 47 ) thermometry is based on the temperature-dependent bonding of 13 C and 18 O within the lattice of carbonate minerals relative to that expected when all isotopes are randomly distributed (Ghosh et al., 2006;Schauble et al., 2006). The clumped isotope geochemistry of carbonates provides a singlephase geothermometer independent of the stable isotopic composition of the parent fluid, and is a frontier in the development of paleo-temperature proxies (Eiler, 2007(Eiler, , 2011. The last decade has seen an increasing use of clumped isotopes in studies of climate change on various geological time scales (

Synthetic Witherite for Standardisation of Clumped Isotope (Δ47) Measurements

“…2021, Guo et al . 2022). Quantitative precipitation of BaCO 3 was selected over CaCO 3 (which is more relevant for natural carbonates in geochemical studies) because BaCO 3 has only one crystal structure, whereas CaCO 3 forms several types of polymorphs, such as calcite, aragonite and vaterite.…”