Research On The Horizontal Well Length And Well Pattern And Spacing Of The Thin Bottom Water Reservoir

Lenticular,thin sandstone of bottom water reservoir belongs to the special particularity,the reservoir is mainly manifested in the thin layer thickness(3m-5m),small oil-bearing area,low amplitude reservoir oil-bearing poor.The reservoir is mainly distributed in the Cretaceous strata of Luliang oil field in the hinterland of Junggar basin,Xinjiang,and there are few reports on the application of horizontal well technology in this type of reservoirs.This paper takes Xinjiang basin in Junggar Luliang area of Cretaceous Hutubi River group of low amplitude,high permeability,lenticular thin sandstone bottom water reservoir as the research object.Combined with the theories and methods of geology,well logging,reservoir engineering and numerical simulation,this paper combined with the practical exploitation of horizontal wells.With the development of horizontal well has the actual mining effect,study the relationship between lenticular thin bottom water reservoir and wellbore length of pressure loss,reservoir adaptability,oil drilling various encounter rate and development effect etc.The range of lens thin horizontal well in bottom water reservoir reasonable length and boundary theory and practical application of the combination of the research results,it has good reliability and applicability,On this basis,the application of numerical simulation technology,studied the thin oil reservoir with bottom water injection production well pattern and well spacing,put forward reasonable injection production pattern and water flooding well spacing for transverse injection,and on-site inspection of the actual mining effect,provide the technical basis for the development of Luliang oilfield horizontal wells and wells net adjustment,provides a method and an important technical reference for similar horizontal wells in bottom water reservoir mining research and application.The main conclusions are as follows:1)Lu 9 well area,Hutubi River Reservoir Group reserves mostly belongs to the lenticular reservoir distribution,most of the flow unit can be deployed in horizontal wells 1-2 port,well network deployment area is usually a rectangular area length and width is limited to the thickness of the oil exploitation conditions of horizontal wells injection.Therefore,it is necessary to optimize the position of horizontal well injection production well network and the corresponding position of vertical well injection well.Through the horizontal injection production well network deployment area(300m*100m,500m*100m,500m*300m)simulation and the position of the horizontal well,horizontal well located in the deployment area center.The horizontal well length is consistent with the length of rectangular deployment area.2)For the oil and gas reservoirs with stable oil bearing,stable thickness distribution and large oil bearing area,the reasonable length of horizontal wells is about 300m.For the complex reservoir oil content,oil layer thickness in the deployment area to meet the conditions of the exploitation of the lens of the oil reservoir,the horizontal well length is 200m-300m.When the thickness of the bottom water layer is less than 2m,the length of the 300m area of the horizontal well is a reasonable length of 200m,and the length of the 500m area of the horizontal well is a reasonable length of 200m-250m.When the thickness of the bottom water layer is greater than 2m,the length of the horizontal well in the deployment area 300m length is 200m.500m length of the deployment area of the horizontal well length is about 300m.3)Considering the comprehensive geological characteristics of Cretaceous Lu 9 well area of Hutubi River of the thin bottom water reserves.Considering the injection wells in reservoir thickness,oil poor edge and bottom water layer thickness,vertical wells using the actual geologic and development characteristics of the actual situation,the injection production well spacing can be controlled in the range of 150m-250m,usually 200m.