CAJ | 학술논문

鄂尔多斯盆地华庆地区长8段砂岩为一套典型的低孔、低渗到特低孔、特低渗的储层，平均孔隙度为8.27％，平均渗透率为0.51×10-3μm2，主要孔隙类型为剩余粒间孔隙，孔隙结构以小型小孔喉和微型小孔喉为主。长8致密砂岩储层经历了压实、胶结、溶解等复杂的成岩作用，其中压实和胶结等破坏性成岩作用使储层的原生孔隙大大减少，且长8储层在镜下发现沥青充填孔隙，降低了储层的物性，导致储层致密。成岩作用对储层的致密化起决定性作用，沉积环境是控制致密砂岩储层形成的基本因素，三角洲前缘砂体中的水下分流河道砂体物性最好；主砂体展布带内中心部位物性好，向两边逐渐变差。随着填隙物含量的增加，储层物性逐渐变差。
악이다사분지화경지구장8단사암위일투전형적저공、저삼도특저공、특저삼적저층，평균공극도위8.27％，평균삼투솔위0.51×10-3μm2，주요공극류형위잉여립간공극，공극결구이소형소공후화미형소공후위주。장8치밀사암저층경력료압실、효결、용해등복잡적성암작용，기중압실화효결등파배성성암작용사저층적원생공극대대감소，차장8저층재경하발현력청충전공극，강저료저층적물성，도치저층치밀。성암작용대저층적치밀화기결정성작용，침적배경시공제치밀사암저층형성적기본인소，삼각주전연사체중적수하분류하도사체물성최호；주사체전포대내중심부위물성호，향량변축점변차。수착전극물함량적증가，저층물성축점변차。
Chang 8 sandstone of the Upper Triassic Yanchang Formation in Huaqing area ,Ordos Basin ,is a typical set of reservoirs with low-ultra low porosity and permeability .Its average porosity is 8.27%and average permeability is 0.51 × 10 -3 μm2 .The main type of pore space is residual inter-granular pore ,and the main type of pore structure is tiny and mi-cro throat.The Chang 8 reservoir has experienced complex diagenesis ,such as compaction ,cementation,and dissolution . The destructive diagenesis of compaction and cementation sharply reduce the primary pores of the reservoir ,besides ,some pores are filled with bitumen ,resulting in the lowering of porosity and permeability and the tightness of the reservoir .Dia-genis is a determining factor in reservoir tightening , while depositional environment is the basic controlling factor of the reservoir physical property .The underwater distributary channel sands in delta front have the best physical property ,and the central part of the sandbody is better than its two sides .With the increasing of interstilital matter ,the physical proper-ties get poorer .