Volumetric filling degree is an excellent indicator of hydrocarbon accumulation for complex or irregular sandbodies.

Neogene hydrocarbon reservoirs are far vertical away from source rocks in Chengdao area, constrained by source rocks, migration distances and vertical pathway.

Sealing capacity of faults and cap-rocks determines the largest accumulation amount of hydrocarbons.

The scatter plot analysis between individual controls and volumetric filling can identify the dominant controls on hydrocarbon accumulation.

Multivariate linear regression analysis was used to quantity the controls on trap filling degree.