多薄层特低孔隙度致密砂岩气藏开发模式研究——以川西洛带气田遂宁组气藏为例  

A development mode of tight sandstone gas reservoirs with ultra-low porosity and multiple thin layers:Examples from Suining gas reservoirs,Luodai gasfield,western Sichuan Basin

作　　者：张岩[1] 邓美洲[1] 卜淘[2] 高伟[3] 詹泽东 王琼仙[1] 刘叶 ZHANG Yan;DENG Meizhou;BU Tao;GAO Wei;ZHAN Zedong;WANG Qiongxian;LIU Ye(Exploration and Development Research Institute,Sinopec Southwest Oil&Gas Company,Chengdu,Sichuan 610041,China;No.4 Gas Production Plant,Sinopec Southwest Oil&Gas Company,Chongqing 402160,China;No.3 Gas Production Plant,Sinopec South-west Oil&Gas Company,Deyang,Sichuan 618199,China)

机构地区：[1]中国石化西南油气分公司勘探开发研究院,四川成都610041 [2]中国石化西南油气分公司采气四厂,重庆402160 [3]中国石化西南油气分公司采气三厂,四川德阳618199

出　　处：《天然气技术与经济》2023年第5期26-32,共7页Natural Gas Technology and Economy

摘　　要：为了建立特低孔隙度、低丰度的多薄层致密砂岩气藏的开发模式,指导同类气藏高效开发,以四川盆地川西洛带气田上侏罗统遂宁组气藏为研究对象,分析了储集层特征、微观渗流机理,指出了该类气藏科学合理的开发模式。研究结果表明:①砂岩、泥岩频繁互层叠置,储集层基质物性较差,为特低孔隙度、致密储层,微观孔隙以细孔—微喉型为主,孔喉体积比偏小,岩心覆压实验结果表明渗透率应力敏感较强;②气藏原始束缚水饱和度中等,气水两相共渗区较大,岩心衰竭实验结果表明采收率中等—较高;③气藏无边、底水,属常压、定容封闭弹性气驱干气气藏;④单井控制储量小,稳产期短,压力、产量递减较快,低压低产期较长。结论认为:①该类气藏以多个薄砂体交互叠置状或透镜状分布为地质特征,为了提高开发效益,按照先评价认识清楚后再投入开发、逐步滚动扩边增储上产的思路开展气田建设工作;②建产期优先开发高产富集区,试验增产工艺;③稳产期依靠直井多层压裂合采,补充新井实现产能井间接替;④递减期依靠老井转层挖潜、增压开采与泡沫排水采气等措施延缓产量递减,同时部署开发调整井进一步提高采收率。Gas reservoirs of Suining Formation,Luodai gasfield,western Sichuan Basin,were taken as examples to analyze reservoir characteristics and microscopic seepage mechanism.And then a rational development mode was built for them,also providing guidance for similar tight sandstone gas reservoirs with ultra-low porosity,low abundance and multiple thin layers in the efficient development.Results show that(i)featured with poor physical properties,these reservoirs exhibit frequent interbedding and superimposition of sandstone and mudstone,which assumes as tight ones with ultra-low porosity.Their pore structure is mainly composed of fine pores to microscopic throat with relatively small pore-throat volume ratio;(ii)their original irreducible water boasts moderate saturation and they have larger area of gas-water dual-phase co-seepage,and core experiments under pressure depletion represent middle to higher recovery efficiency;(iii)without bottom and edge water,they belong to constant volume,closed,elastic gas-drive dry gas reservoirs with normal pressure;and(iv)they are characterized by low well-controlled reserves,short period of stable production,fast decline in pressure and production,and long-term low yield under low pressure.It is concluded that(i)geologically,this kind of gas reservoirs feature multiple thin sandbodies interbedded each other,presenting the lenticular extension.And they should be appraised and then developed progressively for enhanced recovery to increase development benefits;(ii)in the initial production stage,the highly productive and enriched zones will be preferentially developed under normal pressure if necessary;(iii)in the stable production stage,multiple layers will be co-exploited through vertical wells,and additional wells will be drilled to conduct interwell replacement for productivity;and(iv)in the production decline stage,some techniques,such as changing payzone in old wells,pressured exploitation,and foaming drainage gas recovery,may be employed to delay this decline.Meanwhile,development

关 键 词：四川盆地西部 洛带气田 多薄层 特低孔隙度 致密砂岩 孔隙结构 渗流机理 开发技术政策 

分 类 号：TE37[石油与天然气工程—油气田开发工程]