Research Of Sazhong Zone Development Technology Policy Limits In High Water Cut Stage

When the oil field development has entered the development of ultra-high water cut stage,coMPared to the low water content,The ultra-high water cut reservoir has some characteristics,such as,low production rate,large water consumption,more decentralized remaining oil,bad iMPact of the measures taken,deterioration in well condition,declined economic benefits.So,limits on the development of technologies need to be re-adjusted.The Sazhong zone has been developed for 47 years,and now it has entered the period of high water cut stage and decreasing production.The oil field development is faced with the "three-high" situation of high water cut,high degree of recovery,high-decreasing.At present, the oilfield comprehensive aquifer has reached 91 percent.According to the conditions of water flooding exploitation,the effects of measures to increase oil have been deteriorated year by year.The cut differences between the various layer systems have been only 3～4 percentage points.The room of structural adjustment has been very little.The difficulty for the comprehensive adjustment has increased.Therefore,the core displacement experiments and the field data analysis are needed to study the water-drive laws of the high water cut stage reservoirs in Sazhong zone.In this paper,the changes of the oil-water relative permeability curves at high water cut stage are studied by analysis of the cores experimental data of the coring wells,statistical analysis of the field actual data,and reservoir engineering theories and methods.The effects of the geological factors on the oil-water relative permeability rate curve are analyzed.The water-drive laws curve is derived,by the oil-water relative permeability curves,and the up-warping cause and up-warping range of the water-drive curve at the ultra-high water cut stage.The reserves constant is calibrated and the chart of the water-drive curve applicable to high water cut stage is drawn.The development technology policy boundaries at the high water cut stage and the late high water-cut stage are fully summarized and analyzed.The development laws of the high water cut stage in Sazhong Zone are grasped.Based on this study,whether the development technology policy boundaries at the late high water cut stage is applicable to the ultra-high water cut is studied.The development technology policy boundaries,in Sazhong zone is studied to guide the next job of actual production using the application technology economic theory,reservoir engineering theory,material balance principles.