摘要
为了深化对鄂尔多斯盆地北缘东胜气田二叠系下石盒子组盒1段储层展布及其非均质性特征的认识,进一步指导该气田的勘探开发,以东胜气田锦30井区盒1段致密砂岩储层为研究对象,分析了测录井、岩心、化验分析等地质资料,指出了研究区盒1段储层孔隙度、渗透率及砂体展布特征。研究结果表明:①盒1段储层纵向叠置发育,储层内部垂向粒度韵律以复合韵律和均质韵律为主,夹层包括泥质夹层和物性夹层,以泥质夹层为主;②盒1段的3个亚段储层非均质性均较强,其中盒13亚段非均质性最强;③平面上,盒11、盒12亚段在研究区东部相对高孔隙度、高渗透率区发育,盒13亚段在研究区西部相对高孔隙度、高渗透率区更发育。结论认为:①盒1段储层复合连片发育,但孔隙度、渗透率受沉积作用控制较明显,盒1段的3个亚段中,盒13亚段砂体规模更大、物性更好,高孔隙度、高渗透率区分布范围更广;②沉积相与成岩作用共同影响了储层非均质性特征,垂向上,辫状河不同沉积微相岩性及粒度变化大,成分成熟度及结构成熟度存在差异,储层物性变化较大,平面上,辫状河河道摆动迁移频繁,受沉积微相控制,储层非均质性较强;③研究区压实作用较强,黏土矿物发育使储集层物性变差,储层岩石成分的差异导致成岩作用后储层存在明显的非均质性。
In order to clarify the distribution and heterogeneous characteristics of tight sandstone reservoirs in Dongsheng gasfield along the northern margin of Ordos Basin and guide next exploration and development,Shihezi 1 Member in Jin 30 well block was taken as an objective.Some data on mud logging,wireline logging,core,and assay,along with other geological attribute were analyzed to obtain porosity,permeability,and sandbody distribution in the study area.Results show that(1)Shihezi 1 reservoirs are superimposedly developed in the vertical direction.The internal vertical grain rhythm is dominated by compound rhythm and homogeneous rhythm.And in these reservoirs,there are argillaceous interbed and calcareous interbed,among which,the former is more;(2)three submembers subdivided in Shihezi 1 Member,are characterized by strong heterogeneity with the strongest in Shihezi 13 submember;and(3)in plane,both Shihezi 11 and 12 submembers are developed in the eastern high-porosity and high-permeability zone while Shihezi 13 submember in the western high-porosity and high-permeability zone.In conclusion,Shihezi 1 reservoirs are developed continuously,but both porosity and permeability are controlled more by sedimentation.Among three submembers,Shihezi 13 submember ranks the first in sandbody size,physical property,and distribution range in the high-porosity and high-permeability zone.In addition,for these reservoirs,the heterogeneous characteristics are affected jointly by sedimentary facies and diagenesis.Vertically,different microfacies of braided river vary greatly in lithology and grain size,compositional and structural maturity is different,and physical property varies greatly.In plane,braided channel swings and migrates frequently,and under sedimentary-facies control,the heterogeneity is stronger.In the study area,strong compaction and clay-mineral development make the physical property worse,and the compositional difference in reservoir rock leads to obvious heterogeneity after diagenesis.
作者
郝廷
HAO Ting(Exploration and Development Research Institute,Sinopec North China E&P Company,Zhengzhou,Henan 450006,China)
出处
《天然气技术与经济》
2021年第5期7-13,21,共8页
Natural Gas Technology and Economy
基金
国家科技重大专项“低丰度致密低渗油气藏开发关键技术”(2016ZX05048)。
关键词
鄂尔多斯盆地
东胜气田
锦30井区
盒1段
储层非均质性
Ordos Basin
Dongsheng gasfield
Jin 30 well block,Shihezi 1 Member
Reservoir heterogeneity
