Remaining Oil Distribution And Measurement Of Further Exploitation Of The Third Oil Series Of The Fourth Member Of The Qianjiang Formation In WangChang Oilfield Of Qianjiang Sag

Wangchang Oil Field is located at the north of Qianjiang Sag, JiangHan Oil Region, the main part is a long axis of anticlinal structure. The third oil series of the fourth member of the Qianjiang formation in WangChang oilfield buried deeply, and it has a poor reservoir physical property. With the problems such as deepening of waterflooding, water channeling and casing failure well increasing appeared in succession, development effect became worse. This paper use reservoir engineering methods and numerical simulation methods to study the rule of underground oil and water sports and the rule of remaining oil distribution, which provide technical support for the efficient adjustment and decisionIn this paper, I analysis the geological features and current status of exploitation of the third oil series of the fourth member of the Qianjiang formation in WangChang oilfield, on this basis, I establish a geological model; and with the combination of reservoir production data, numerical simulation of the dynamic. Through geological reserves, oil production, water production, water cut, etc. history matching precision, get the remaining oil saturation distribution maps and the reserves abundance distribution maps of the tree small layers of the third oil series of the fourth member of the Qianjiang formation in WangChang oilfield. Combined with relevant geological background and reservoir performance, from geological factors (structure factors, reservoir heterogeneity), and the development factors (water flooding inequality, voidage-injection imperfect, oil line damage, etc.) to research the remaining oil distribution mechanism. By using the non-dimensional injection curve, water drive curve, decline curves, growth curves and other reservoir engineering methods to analysis the final recovery efficiency and recoverable reserves of the third oil series of the fourth member of the Qianjiang formation in WangChang oilfield, at the meantime hold the current exploitation degree and remaining oil distribution on the whole, the average recovery was calculated as 43.17% and recoverable reserves as 4,394,700 tons.In this paper, I use the numerical simulation method to optimize well network, well spacing, production rate, injection-production ratio and other related production target respectively. To the Wang 4-6-1B well in well network imperfect region as the design center, I design the inverted nine spot flooding pattern, the inverted seven spot flooding pattern and row well pattern; I also design a 200m,250m,300m,350m, 400m, etc.5 sets of well spacing. With numerical simulation, we obtain when the well pattern is the inverted nine spot flooding pattern and the well spacing is 300m, development effect is best. On this basis, I design 0.8,1.0,1.2,1.4,1.6 other five kinds of production rate and 0.8,0.9,1.0,1.1,1.2 other five kinds of injection-production ratio to optimize, with numerical simulation, we obtain that oilfield will get better development effect and higher recovery. Finally,according to the results of reservoir simulation, combined with the dynamic development, I comprehensively analysis the readjustment and disposition of the third oil series of the fourth member of the Qianjiang formation in WangChang oilfield, make it three layers to adjust the deployment, deploy a total of 37 oil wells,9 water wells. After the program adjusted, Oil recovery increased by 4.76%, the cumulative oil production increase of 48.44 x 10~4t, recovery ratio reached 47.93% at the forecast period.