Transmission model of secondary gas reservoir on the basin margin of Jiyang Depression

Heavy oil and gas have an association in a shallow fault basin reservoir. More than 50% of shallow gas reservoirs came from the biodegradation of heavy oil. However, there is little research on the migration process from the heavy oil reservoir to the shallow gas reservoir. Through the study of the carrier system type, distribution and elements of heavy oil and shallow gas reservoirs, two models were established, and the migration controls were clarified. There are two carrier system types: lateral and vertical. Lateral migration mainly developed in the high convex belt of the basin, and the shallow gas reservoir was distributed over the side of the heavy oil reservoir. The transmission process was dominated by lateral migration. Vertical migration also took place through diffusion along faults. Vertical migration mainly developed in the depression and low convection zone, and the shallow gas reservoir was located directly above the heavy oil reservoir. The transport process is dominated by vertical migration through faults.