Research And Application Of Separate-layer Development Of Lotus Strata In Lei 11 Block GS Oilfield

GS oil field is located at the northern end of the western slope of the west depression of the Liaohe fault depression,which is a complex fault block with low resistance and low water content.The main development target layer is the lotus oil layer,oil area of 2.42km2,petroleum geological reserves of 385×104t,recoverable reserves of 152.46×104t,the estimated recovery rate of 39.6%.Since the development of the block in 1988,it has been carried out by means of a set of wells,which can not make full use of the remaining oil potential of each set of reservoirs,resulting in the increasingly serious water-Between the layers of contradictions,production scale continued to decline.In this study,the tectonic characteristics,sedimentary microfacies distribution characteristics,reservoir characteristics and petroleum geologic reserves are carried out from the description of fine reservoirs.It is recognized that the tectonic morphology of the lotus reservoir is mainly broken structure and broken anticline the average porosity is 19.4%,and the average permeability is 125.02 mD,which is the mesoporous osmotic reservoir.The reservoir is composed of sandstone and conglomerate.On the basis of this,this study is based on the characteristics of the block,the subdivision of the reservoir unit in the longitudinal direction,the stratified development and exploitation on the plane,the combination of the development of the well pattern,the optimization of the stratified injection and mining parameters and the horizontal well deployment parameters.Since the development of pilot experiments in stratified development in 2011,there have been 15 new wells,of which 29 are straight wells and 16 are horizontal wells,and 41 have been put into production.The output of blocks has been increasing year by year,and the development indicators have been greatly improved.Layered development before the 144 t increase 220t;oil recovery rate from 0.85% to1.15%,the new crude oil production capacity of 8.1×104t.In recent years,with the construction of capacity to strengthen and improve the straight well injection and production wells and horizontal wells injection and production wells,the new water drive control reserves of28×104t,water drive reserves control from 50.5% to 80%.