The clumped isotopic composition of carbonate‐derived CO2(denoted Δ47) is a function of carbonate formation temperature and in natural samples can act as a recorder of paleoclimate, burial, or diagenetic conditions. The absolute abundance of heavy isotopes in the universal standards VPDB and VSMOW (defined by four parameters:
Clumped isotope studies on CO2, Δ47, that is the excess in the isotopologue containing both13C and18O at mass 47, can be very useful since they can give temperature estimates independent of the bulk isotopic composition. The measurement itself can be affected by a number of items. Here we develop a data processing model to examine the effects different interferences might have on the final calculated value. It incorporates known issues, for example, pressure baseline,17O excess, and shifts in absolute ratios for primary reference materials and parameters used for17O correction. We also included linearity effects as well as differences in isotopologue absolute abundances at a given
- NSF-PAR ID:
- 10367879
- Publisher / Repository:
- DOI PREFIX: 10.1029
- Date Published:
- Journal Name:
- Geochemistry, Geophysics, Geosystems
- Volume:
- 20
- Issue:
- 7
- ISSN:
- 1525-2027
- Page Range / eLocation ID:
- p. 3569-3587
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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