Time-capsule concretions: Unlocking burial diagenetic processes in the Mancos Shale using carbonate clumped isotopes

For clumped isotope analysis (Δ47), hydrocarbon and organic molecules present an important contaminant that cannot always be removed by CO2 purification through a Porapak‐Q trap. Low‐temperature oxygen plasma ashing (OPA) is a quick and easy approach for treatment; however, the impact of this treatment on the original carbonate clumped isotope values has never been fully studied.