摘要
松辽盆地北部徐家围子断陷沙河子组源储一体,具有形成致密气的地质条件。研究表明,沙河子组纵向上发育4个三级层序,发育扇三角洲和辫状河三角洲2种沉积体系,砂体沿断裂边部呈裙带状分布于断陷盆地,表现为粗碎屑、短物源、快相变的特点。烃源岩分布面积广、厚度大、地化指标好、生烃强度高。储层物性为低孔低渗,以纳米级孔隙为主,储层空间类型以次生溶孔为主。气藏分布具有“三控”的分布规律,即有效烃源岩控制气藏发育区、有利相带控制有利储层发育带、储层发育程度控制气藏富集。近几年按照“相定井型,先直后平”的勘探思路,部署的探井在安达、徐东、徐西和徐南地区相继获得工业突破,采用类比法估算资源量3 520×10^8m^3,沙河子组致密气展现了满凹含气的规模场面。下一步攻关方向为开展致密气效益动用一体化现场试验,探索工业化水平井设计方法。同时,开展沙河子组页岩气成藏条件研究,进一步拓展沙河子组勘探潜力。
Shahezi Formation in Xujiaweizi Fault Depression in North Songliao Basin is the integration between the source rocks and reservoirs,and moreover has the geological conditions of accumulating tight gas.The study results show that Shahezi Formation has four three-order sequences vertically and develops two types of sedimentary systems i.e.fan delta and braided river delta.The sandbodies are distributed in the skirt pattern along the fault edge of the fault depression basin,which are characterized by coarse clastic,short material source and fast facies transition.The hydrocarbon source rocks are characterized by wide distribution,large thickness,good geochemical indexes and high hydrocarbon generation intensity.The physical properties of the reservoir are low porosity and low permeability,mainly nanoscale pores,and the spatial type of the reservoir is mainly secondary dissolved pores.The distribution of the gas reservoirs has the distribution law of“three controls”.The effective source rocks control the developed area of the gas reservoirs,the favorable facies belts control the favorable reservoir development zones,and the reservoir developed degree dominates the accumulation of the gas reservoirs.In recent years,according to the exploration thinking of“facies determines well type,first vertical well and then horizontal well”,the deployed exploring wells have successively achieved the industrial breakthroughs in Anda,Xudong,Xuxi and Xunan regions,and the resource volume was estimated by analogy method at 3 520×10^8m^3.The tight gas in Shahezi Formation shows a scale full of concave gas.The next research direction is to carry out the integrated field test of the tight gas effect and utilization and furthermore to explore the design method of the industrial horizontal wells.Meanwhile,the shale gas accumulation conditions in Shahezi Formation will be studied to further expand the exploration potential of Shahezi Formation.
作者
印长海
杨亮
杨步增
YIN Changhai;YANG Liang;YANG Buzeng(Exploration and Development Research Institute of Daqing Oilfield Co Ltd,Daqing 163712,China;Heilongjiang Key Laboratory of Tight Oil and Shale Oil Accumulating Research,Daqing 163712,China)
出处
《大庆石油地质与开发》
CAS
CSCD
北大核心
2019年第5期135-142,共8页
Petroleum Geology & Oilfield Development in Daqing
基金
国家科技重大专项“致密气资源潜力评价、富集规律与有利区带优选”(2016ZX05047001)
中国石油天然气股份公司科技攻关项目“松辽盆地北部致密砂砾岩资源潜力及富集规律研究”(2012E260302)
关键词
致密气
沙河子组
砂砾岩
断陷盆地
松辽盆地
tight gas
Shahezi Formation
conglomerate
rift basin
Songliao Basin
