Presentation Profile
How clumped isotope analyses drive a deeper understanding of petrochemical processes
Currently Scheduled: 10/12/2022 - 10:50 AM - 11:20 AM
Room: Floral Hall A2
Main Author
Darren Tollstrup - Thermo Fisher Scientific
- Nina Albrecht - Thermo Fisher Scientific
Abstract:
Classical stable gas isotopes, such as δD, δ13C, and δ18O, are well-established and valuable tools in various fields of earth sciences. They aid in constraining genetic mechanisms, provenance, transport processes, and formation temperatures. Their geothermometric usability is however limited as they lack an absolute temperature dependency. Clumped isotope geochemistry overcomes this limitation since the equilibrium distribution (‘clumping’) of heavy isotopes within multiply substituted molecules is solely dependent on the formation temperature.
The most investigated clumped isotope systems are clumping in CO2 and in CH4. It has been demonstrated that the associated thermometry delivers highly precise carbonate and methane formation temperatures. When two clumped isotopologues of one species are analyzed, it is even possible to pin down kinetic biases in cases where a sample is deviating from the expected thermodynamic equilibrium. Apart from geothermometry and the identification of kinetic processes, the addition of clumped isotope signatures to the classical stable isotope geochemist’s toolbox enables a refined forensic source apportionment of natural samples.
In this presentation we will illustrate the analytical setup (IRMS and HR-IRMS) to perform the above-mentioned measurements, and we will focus on how clumped isotopes add fresh insights into petroleum research. Besides CO2 and CH4, we will also give a perspective on the potential of clumped isotope analyses in N2, and H2, as typical compounds in natural gas reservoirs.
