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With oil field infill gradually in north of sa development area, each series of well network production target getting worse gradually, intersecting with old well network stratigraphic position, and polymer flooding well network use part of water driving old well, making the contradictory of layer well network concatenate and dynamic regulation intensely. Especially in North 2 East, as the block of infill adjustment proceeded earliest, acquired better developed effect at the beginning of regulation, but with the deep development of the field, after the phase of extra high water cut, exposed gradually some problems such as the perforating interval is too long, the contradiction of interlamination is obvious, the high water cut of multilayer is serious, bringing huge difficulty to dynamic analysis regulation. At present, the total water cut of blocks reached 94.8 percent, is the block of highest water cut in single oil area, in the same water cut conditions, the degree of reserve recovery in North 2 East is lower obviously than other three blocks in single oil area. Zonal testing and production practice are difficult to meet the need of further water control for potential tapping, and tertiary infill, injection-production system regulation has limited effects on solving problems in the block. To tap the potential of remaining oil fully, enlarge the formation and connotation of well network regulation, launch the test of the recombination of series of strata improving the water driving developed effect, according to interlayer develop character, redistrict the series of strata and rematch the injection-production well network, apply different develop countermeasures to different series of strata, lessen the interference of interlayer by a large margin, fully give play to the oil layer potential, improve the effect of block develop.This paper analyzes the five major factors that influences block development effect through integrated study of mining status of block, divide layer system anew and matches flood pattern anew according to development characteristic of interlayer, makes use of different development countermeasure to different layer system, and makes sure of the technical ideas of subdivision of layer system, independence of well network, optimization of well spacing and conducive to adjust. Refine development layer system based on the layer system adjustment, subdivide and restructure layer system of infilling once and twice which has long perforated interval and prominent interformational contradictions; After deploying well network, combine the new wells with the old Wells, matche flood pattern anew, realize the aim of independence of well network, optimization of well spacing, perfect injection-production and concatenate well with original well network, and leave some space to tertiary oil recovery. In July, 2010, experimental site is subdivided and restructured into four sets of independent well network after adjustment, interformational divergence and control degree of well network are improved obviously, average perforated interval shortened from 163cm to 93cm, permeability contrast reduced from 17.5 to 6.7, multidirectional connected proportion add 25.6 percent, per well production reach 4.0t in early days of the new wells are put into production which is 1.2t more than project designed. The natural decrease reachs 2 to 3 percentage points as expected per year, the water flooding recovery efficiency increases by 2.27%.
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