The geological models of oil-gas flow mechanical simulation were studied for the different oil-gas dispersion processes after their accumulation by use of both digital and physical simulations. The mechanism of fluid field decided the difference of oil-gas in a dispersion process and the flow independence in oil and gas layers. The main results were as follows. 1)Petroleum leakage at a local high point little affected petroleum preservation of another high point, or only had small influence. 2)Although leakage at one high point, the natural gas in both the high points could be produced. 3)In an accumulation belt which experienced disruption, the distribution of oil reservoir isolated generally, while the distribution of gas reservoir often grouped. These results must have an important theoretical significance for guiding the oil-gas exploration and development activities in the same accumulation belt, which was demonstrated to be a good direction in the Ordovician oilfield in Lunnan, the Tarim Basin.