苏里格气田46区盒8段致密砂岩储层特征及主控因素

Characteristics of tight sandstone reservoirs and its main controlling factors of He 8 Member in Block 46,Sulige Gas Field

为查明苏里格气田46区盒8段致密砂岩储层特征及主控因素,文中利用铸体薄片、岩心物性、扫描电镜、压汞、T2核磁等测试分析,对盒8段致密砂岩储层开展了系统研究。结果表明:研究区盒8段致密砂岩储层储集空间类型主要为粒间溶孔、粒内溶孔、杂基孔,平均孔隙度为6.93%,平均渗透率为1.620×10-3μm2,为一套特低孔—超低孔、超低渗储层。孔喉分布不均匀,分选相对较差,以中小孔-细微喉组合为主。低体积分数岩屑、高体积分数石英、大粒径颗粒是优质储层发育的物质基础;沉积作用保留的原生粒间孔隙是次生孔隙、成岩裂缝发育的基础,也是寻找优质储层的关键。

In order to find out the characteristics and main controlling factors of tight sandstone reservoir in He 8 Member in Block 46,Sulige Gas Field,the tight sandstone reservoir of He 8 Member was systematically studied by the analysis of cast thin section,core physical properties,scanning electron microscopy,mercury penetration,T2 nuclear magnetic and other tests.The results show that the storage space types of tight sandstone reservoir in He 8 Member in the study area are mainly intergranular dissolved pores,intragranular dissolved pores and heterogeneous matrix pores,with an average porosity of 6.93%and permeability of 1.620×10-3μm2,which is a set of very low to ultra-low porosity and ultra-low permeability reservoirs.The pore throats are not evenly distributed,and the sorting is relatively poor,mainly in the combination of small and medium pores and fine throats.Low volume fraction cuttings,high volume fraction quartz and large size particle are the material basis for the development of high quality reservoirs.The primary intergranular pores retained by sedimentation are the basis for the development of secondary pores and diagenetic fractures,and are the key to finding high quality reservoirs.