Study On Development Characteristics And Distribution Of Remaining Oil Of CG1 Buried-hill Oilfield

The CG1 buried-hill oilfield is the one which is earlier put into development in the plent of Guangrao oilfields,Shengli oilield,which is a fracture cave type carbonate monadnock of Buried shallow,strong bottom water,extra heavy oil,and dissolution type.The reservoir has suffered for a long period of weathering,denudation and leaching,dissolution and recrystallization and frequent tectonic movement transformation.The development effect is influenced by many factors.At present,the reservoir is in the late stage of high water cut development,the production level is low,the remaining oil potential is large,but the distribution is more complex.Need to use a variety of reservoir engineering methods to study.Based on the study of the geological and development characteristics of the oil reservoir,studied the influence of oil well productivity and watercut by the degree of fracture development,oil property,well type,development mode,liquid production strength etc.CG1buried-hill oilfield developed high angle fractures,and the bottom water energy is sufficient,development features Performanced as the initial capacity was higher,but affected by the cone bottom water,watercut rised fast,productivity declined sharply.At the same time,the degree of fracture development,Development mode,well types and liquid production intensity Have an important influence on the productivity and rising speed of water.Then,based on the geological characteristics of the reservoir,Combinated of residual oil distribution in the fracture cavity carbonate reservoir,Summarized 6 types of distribution pattern:Attic type,dense block type,bottom water seal block type,Low amplitude residual hill type,High diversion channel near the Hole-crack type and Separated fracture cavity type.On this basis,Combinated reservoir engineering method such as reservoir numerical simulation,established potential countermeasures which were applicable to the remaining oil distribution models.For the uncontrolled residual oil of bigger distance between wells,intended to drilling new wells,expected to add reserves of up to 160×10~4t.For the residual oil of smaller distance between wells,intended to take acid fracturing,oil well deepening,large pumping liquid,water plugging,shut in to decline cone and other measures,the average of increase of oil achieved2.7t/d,cumulative increase of oil achieved 44509t,Has achieved a better effect of increasing production.At the same time,this paper has important theoretical significance to guide the development and improve the oil recovery of the same type of oil reservoir.