大民屯凹陷西部沙河街组沙三、沙四段储层特征及影响因素  

Reservoir Characteristics and Influencing Factors in Sha3 and Sha4 Member of Shahejie Formation in the west of Damintun Sag

作　　者：胡振华[1] 

机构地区：[1]中国石油辽河油田公司,辽宁盘锦124010

出　　处：《中外能源》2014年第9期56-60,共5页Sino-Global Energy

基　　金：中国石油天然气股份有限公司重大科技项目;编号:060105-2

摘　　要：研究区位于辽河坳陷大民屯凹陷西部,南起沈281井,北至沈299井,东起胜11井,西至大民屯凹陷边界,面积约为300km2。研究区沙四段扇三角洲相扇群状分布,前缘砂砾岩体沉积厚度大,为有利沉积相带。沙三段三角洲、河流相沉积砂体分布相对稳定。沙河街组含油层系主要分布在沙四段和沙三段中下部。近年来,大民屯凹陷主要勘探工作集中在潜山上,古近系勘探少有发现。从沉积学和储层岩石学特征入手,结合常规岩石薄片、铸体薄片、扫描电镜、孔渗分析、压汞实验分析结果,对辽河盆地大民屯凹陷沙河街组沙三段、沙四段储层特征及影响因素进行研究。结果表明,沙四段多为低孔特低渗储层,储集空间为原生孔隙、次生孔隙和裂缝。沙三段储层成分成熟度和结构成熟度相对较高,原生孔隙得到一定保存,储集性能好,发育中孔中-低渗储层。沉积作用、成岩作用、物源区母岩岩性及断裂活动,是导致储层物性复杂化的主要影响因素。Research area locates in the west of Damintun sag in Liaohe depression with the area of 300km2, Shen281 well in the south,Shen299 well in the north,Shengll well in the east and border of the Damintun sag in the west.The facies of fan delta in Sha4 member of Shahejie formation of the research area distributed as fan group is the favorable sedimentary facies tract for its thick sedimentation of the front glutenite body.The distribution of sedarenite in the delta and the fluvial facies in Sha3 member of Shahejie formation is relatively stable.Hydrocarbon reservoir assemblage in Shahejie formation mainly distributes in Sha4 member and mid-lower part of Sha3 member.In recent years,the exploration of Damintun sag is focusing on the buried hill with little foundation in Eogene.Based on the characteristics of sedimentology and reservoir petrology,reservoir characteristics and influencing factors in Sha3 and Sha4 member of Shahejie formation in Damintun sag of Liaohe basin are studied combined with the analytical results of conventional rock slice, cast slice,SEM,porosity and permeability analysis and mercury injection experiment.The results show that lowporosity and extra-low permeability reservoirs mainly distribute and reservoir space is primary pore ,secondary pore and fractures in Sha4 member.Middle porosity and middle-low permeability reservoirs developed in Sha3 member with relatively high compositional maturity and textural maturity and good storage,and the primary pore is preserved on certain degree.Sedimentation,diagenesis,lithology of mother rock in the provenance and fracture activity are the main factors influencing the complication of physical property of the reservoirs.

关 键 词：储层特征 影响因素 沙三段 沙四段 沙河街组 大民屯凹陷 

分 类 号：P618.13[天文地球—矿床学]