Analysis of the subsag types and corresponding origins demonstrate that only the types of those oil-rich or sub-oil-rich subsags can be expected to have potentials for accumulating large or medium size oil fields.

The five key factors that are responsible for PY4-2 oil pool include rich source kitchen,marginal fault of sag, assemblage of reservoir and seal of delta front sandstone and mudstone,compressing structure as well as appropriate time of oil migration and trap formation.

Application of de-filtration technique in fracturing of Fulin Sag;

The simulation test of petroleum migration path around BANGHU syncline indicates that this model can reflect accurately the rules of oil and gas migration in source sag.

Banghu Syncline is the main source sag in Qianjiang Depression.

Despite their long history of development, some oil-rich sags still have a large quantity of residual resource in the forms of five potential play targets: undeveloped sags in the developed depression, hidden reservoir, complex fault structure, and deeply buried and small hills and some special reservoirs.

Based on the research and exploration of lithostratigraphic reservoir in the Jizhong depression of the Bohai Bay basin and Erlian basin, the hydrocarbon distribution in a continental oil-rich sag has "complementarity" feature, viz.