天然气勘探与开发2024，Vol.47Issue(1)：73-82,10.DOI:10.12055/gaskk.issn.1673-3177.2024.01.009
四川盆地公山庙油田中侏罗统沙溪庙组一段致密油藏流体渗流特征
Fluid flow behaviors in tight reservoirs of the Middle Jurassic Shaximiao 1 Member,Gongshanmiao oilfield,Sichuan Basin
摘要
Abstract
Tight oil reservoirs are characterized by complex pore structure,high resistance in fluid flow,and low production,resulting in poor development benefits.Thus,taken the low to ultra-low permeability tight sandstone oil reservoirs of of the Middle Jurassic Shaximiao 1 Member,Gong-shanmiao oilfield,central Sichuan Basin,as examples,numerous experimental studies,such as low-velocity fluid flow,constant-rate water flooding and spontaneous imbibition,were conducted on the basis of another one experiment on rock wettability.Experimental results show that(i)generally,the reservoir rocks of Shaximiao 1 Member represent a weak hydrophilic feature.When core samples are fully saturated with formation water,the water phase flow curve assumes a straight line passing through the coordinate origin.There is no start-up pressure or start-up pressure gradient in the forma-tion-water single-phase flow which is consistent with the Darcy's law;(ii)when establishing an irreducible water saturation via oil displacing water,water membrane adsorbed on pore surface may reduce oil-phase flow channels,whereas the Jamin's effect in two-phase flow may increase additional resistance to oil-phase flow.The low-velocity flow curve of oil phase does not pass through the coordinate origin,indicating the existence of start-up pressure or its gradient.The lower the reservoir permeability,the higher the start-up pressure or pressure gradient;(iii)both displacement rate and rock permeability exert great impacts on the performance of water flooding.At a higher rate,not only fingering of injected water in some larger pores but water channeling along fractures are the main controls on the decline of flooding efficiency;(iv)rock permeability may affect imbibition displacement obviously.And for fracture samples,the imbibition displacement efficiency is bigger than that in matrix samples;and(v)after large-scale fracturing in tight oil reservoirs,the induced fractures with high permeability can reduce start-up pressure and its gradient with effect.And as an important means,the single-well huff and puff(water-oil exchange by imbibition)may also ensure these reservoirs in the long-term stable production.The research results are significantly referential for the development of tight reservoirs or shale oil.关键词
致密油藏/润湿性/渗透率/低速渗流/启动压力/渗吸实验/水驱油效率Key words
Tight oil reservoir/Wettability/Permeability/Low-velocity flow/Start-up pressure/Imbibition experiment/Water-flood-ing efficiency引用本文复制引用
周克明,宋林珂,张容,袁小玲,刘婷芝,余华洁,缪海燕,张琳羚,王艳,何家欢,肖红林..四川盆地公山庙油田中侏罗统沙溪庙组一段致密油藏流体渗流特征[J].天然气勘探与开发,2024,47(1):73-82,10.基金项目
中国石油天然气股份有限公司2019年天然气开发前期评价项目(编号:西南司计财2019-248). （编号:西南司计财2019-248）
