Intramolecular 13C isotope distributions of butane from natural gases

Maxime Julien, Mark J. Goldman, Changjie Liu, Juske Horita, Christopher J. Boreham, Keita Yamada, William H. Green, Naohiro Yoshida, Alexis Gilbert

Research output: Contribution to journalArticlepeer-review

9 Scopus citations


A single-step method allowing the measurement of 13C intramolecular distribution of butane isomers (n- and i-butane) from natural gas samples was developed. The method builds up on the one that has been developed for propane, using on-line pyrolysis followed by isotope analysis of the pyrolytic fragments. The isotopic filiation between n-butane and its pyrolytic fragments was elucidated using samples spiked with 13C on terminal positions. The isotopic filiation for i-butane could not be shown experimentally due to the lack of commercially available enriched i-butane. We thus used a recent model named Reaction Mechanism Generator (RMG) to assess the origin of the fragments arising from i-butane pyrolysis. Butanes from natural gas samples from the Carnarvon Basin (Australia) and the Arkoma Basin (USA) were analyzed. The results are consistent with a model for thermogenic natural gas generation and suggest that combined intramolecular isotope composition of propane and n-butane can be related to the gas maturity. In addition, the method allows the detection and shed light on the mechanism of n-butane and i-butane biodegradation in natural gas reservoirs.

Original languageEnglish
Article number119571
JournalChemical Geology
StatePublished - May 20 2020


  • Butane isomers
  • Carbon isotopes
  • Hydrocarbons
  • Intramolecular isotope
  • Natural gas


Dive into the research topics of 'Intramolecular 13C isotope distributions of butane from natural gases'. Together they form a unique fingerprint.

Cite this