THE DEVELOPMENT WELL-PATTERN OF LOW AND ANISOTROPIC PERMEABLITY RESERVOIRS

Low permeability reservoirs commercial development is usually obtained by fracturing stimulation.The development of low permeability reservoirs is different from that of normal reservoirs because of the appearance of hydraulic fractures.Severe heterogeneity usually exist due to the permeability anisotropy resulted from developed or tensile natural fractures in low permeability reservoirs.As a result,it is necessary to take into account the effect of heterogeneity of both hydraulic fractured and permeability while planing well pattern.This paper presents the research of inverted nine_spot pattern which is normally used in the development of low permeability reservoirs and modified inverted nine_spot pattern and rectangular pattern.It shows that higher oil recovery and economic efficiency would be achieved by adopting the rectangular pattern if the azimuth of hydraulic fracture is clearly known.