Laboratory experiments in microcosms monitoring the hydrocarbon composition of degraded oils are used with carbon isotopic compositions of gas and oil samples taken at wellheads and a Rayleigh isotope fractionation box model to elucidate the mechanisms of hydrocarbon degradation in reservoirs. The data imply a common methanogenic biodegradation mechanism in subsurface degraded oil reservoirs resulting in consistent patterns of hydrocarbon alteration.
- D. M. Jones
- I. M. Head
- S. R. Larter