Anaerobic microbial degradation of crude oil is the main reason of the formation of heavy oil reservoir and associated gas reservoir. In order to study the formation process of heavy oil and associated gas by anaerobic microbial degradation of crude oil,shallow gas and heavy oil in Linfanjia area were studied. The heavy oil generated from the same source rock was selected for biodegradation experiment using oil-degrading bacterial consortium of the anaerobic microbe. It was found that the thin oil could be ...