| How to improve the oil-water displacement efficiency which is involved in the fieldwide rate and economical efficiency , concerns the oil business all over world. Especially in china , nearly 90 percent of oil fields are of continental deposit reservoirs, multiple pay beds, strongly heterogeneous formations Jfurthermore, they have been produced with the development regime of early-stage waterflooding . That will mean recovering 30-50 percent of commercial reserves during high water-cut stage (water cut between 80 percent and 98 percent),so that this stage will become very important in the oil field development history. What directly influences the production economic efficiency of the old field is whether we could predict correctly the distribution of remaining oil . Field waterflooding performance has indicated the distribution of remaining oil is directly related to the reservoir heterogeneity. So, to characterize detailedly and quantitatively the reservoir heterogeneity is a key to make sure the distribution of remaining oil and make decision to lay out an oil field.The field development is a process of reducing the influence of the reservoir heterogeneity. The adaptability of the development reservoir combination and the flooding pattern to the reservoir heterogeneity is a main factor to determine the flooding efficiency. The proper development reservoir combination and flooding pattern make the effects of the reservoir heterogeneity reduce to the lowest level , so the flooding sweep efficiency and the recovery efficiency will be optimized. One of the important ways to improve the flooding efficiency is to boost the adaptability of the development reservoir combination and the flooding pattern to the reservoir heterogeneity, for the reservoir heterogeneity is objective and not altered by people. Therefore, it is significant theoretically and practically to discuss how to boost the adaptability of the injection-production system to the reservoir heterogeneity and lay down the economical, technical and policy parameters of the flooding pattern on the basis of building the detailed and quantitative geological model of reservoir for the optimized arrangement of the old field development adjustments.In the face of great challenges to improve the flooding efficiency during the high water cut stage, this paper has explored actively the new theories and methods of reservoir description, remaining oil prediction and flooding pattern setting, drawn up a technical line that regards the reservoir geological database and the conceptual model as its foundations, regards the reservoir stochastic modeling ,the reservoir numerical simulation and the remaining oil predictable techniques as its means, regards the distribution of remaining oil and its controls as its research objects ,and regards the optimization of the flooding pattern parameters and adjustment and arrangement of the production measures as its goals. Taking an example of shuanghe oil field (lies on the southern verge of Biyang depression in Nanxiang basin, its reservoirs are interpreted to be fan delta deposit, consist mainly of sandstone and conglomerate, are good in petrophysics and strong in heterogeneity. 90 percent of its petroleum reserves are dispersed in the fan delta front. And now ,it is in the development later stage )in the Henan oildom, this paper has explored actively the ways of enhancing the water drive recovery efficiency and obtained some paramountfruits.1.The detailed prototype model of fan delta front reservoir and some geological knowledges that will be required to generate a stochastic model of heterogeneous reservoirs were established and acquired based on the dense pattern. For example, The average ratios of width/thickness and length/width of the main microfacies sandbodies, the structure of permeability of each microfacies sandbody and so on.2.The detailed conceptual model of fan delta front reservoir, was built with analyseing the distribution of sandbodies and petrophysical properties3.The stochastic models o...
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