Study On Yushulin Oilfield Eastern 14 Block Development Adjustment Scheme And Effect Evaluation

Determination the reasonable development adjustment scheme is the key of improving recovery and retarding production decline in the later stage of oilfield development.After the first-staged well pattern infill of Yushulin Oilfield Estern 14 Block the injection effect is not obvious and production declines quickly.The effect of development adjustment is unsatisfactory.Therefore this thesis takes Estern 14 Block as research object,study the problems exiting in development so far,establish the geological model and numerial simulation model and design the later stage adjustment scheme.With the method of numerial simulation,the thesis optimize combination well pattern of horizontal and vertical wells in water flooding zone and gas flooding zone and the cracks length of large scale fractured oil and water wells.The thesis determines the adjustment scheme in the later stage and provide basis for Eastern 14 Block scientific development by the meaning of economic benefit comparison.Through the thesis' study,the main research results are as follows:(1)Generally analyse and evaluate the development characteristic of Eastern 14 Block,obtain the problems exiting in the current development and provide basis for the next adjustment;(2)Establish Eastern 14 Block 3D geological model and obtain the geological model and refined reservoir parameters distribution model;(3)Establish Eastern 14 Block numerial simulation model,run the history match of production history and obtain the distribution of current block pressure,saturation and so on in plane and vertical cross section;(4)Design the later stage adjustment scheme,optimize the best scheme for combonation well pattern of horizontal and vertical wells through simulation:transfer central injection wells to horizontal injection wells;(5)Optimize the scale of fractured oil and water wells through fracture simulation:the optimized fracture length of side wells is 30?60m,namely penetration ratio is 0.1?0.2;the optimized fracture length of corner wells is 120-150m,namely penetration ratio is 0.4?0.5;the optimized fracture length of injection wells is 60?90m,namely penetration ratio is 0.2?0.3;(6)Compare and analyse the economic benefit of large scale fractured vertical wells and horizontal injection wells.Fractured vertical wells's benefit is higher than combination well pattern after five years,ten years,fifteen years development.Fractured vertical wells are better than combination well pattern.So the thesis provide scientific basis for the block later stage development.