Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
9458016 | Applied Geochemistry | 2005 | 18 Pages |
Abstract
The extremely high S oil samples (>10%) underwent biodegradation of normal alkanes resulting in a degree of concentration of S in the residual petroleum, although isoprenoid alkanes remain showing that biodegradation was not extreme. Interestingly, the high S oils occur in H2S-rich reservoirs (H2S up to 92% by volume) where the H2S was derived from bacterial SO4 reduction, most likely in the source rock prior to migration. Three oils in the Jinxian Sag have δ34S values from +0.3â° to +16.2â° and the oil with the highest S content shows the lightest δ34S value. This δ34S value for that oil is close to the δ34S value for H2S (â¼0â°). It is possible that H2S was incorporated into functionalized compounds within the residual petroleum during biodegradation at depth in the reservoir thus accounting for the very high concentrations of S in petroleum.
Related Topics
Physical Sciences and Engineering
Earth and Planetary Sciences
Geochemistry and Petrology
Authors
Chunfang Cai, Richard H. Worden, George A. Wolff, Simon Bottrell, Donglian Wang, Xin Li,