Establishment Of Effective Displacement Pressure System In Xin Li Oilfield Ⅵ Region

The permeability of Xin Li Oilfield Ⅵ region in FuYu reservior is lower than10×10-3μm2，So it is a typical low-permeability reservior by the classfication of LiDaopin．The flow law is no longger conform the typical flow law,because of the lowpermeability．It exists a starting pressure gradient．Studies have shown that，in the process ofwater injection develepment，effective injection—production relationship can be established ifonly the dfivmg pressure gradient call balance with the starting pressure gradient．So the studyof ultimate injection—production well spacing is very important for low-permeabilityreservior reasonable development，which can establish a effective injection—productionrelationship．In this paper，basic on tile low permeability flow characteristics and large number ofreferenced literature and related research results，it qualitatively analized the factors whichaffect the pressure gradient；the starting pressure gradient of study area was calculated，and itestablished the related curve about startion pressure gradient and permeability．And，the studyreservior had been classfied by the reservior heterogeneity and mercury data of Xin Li OilfieldⅥ region．Based on the classfication，reasonable well pattem of study area was definite bynumerical simulation．And the limit well spacing of study area was calculated with the aid ofthe improved limit well spacing formula.The standard of effective displacement pressuresystem establishment was formed by the reaserch of pressure system and limit well spacing.