辽河滩海西部凹陷古近系碎屑岩储层成岩作用及其对储层物性的影响  

Diagenesis and Its Influence on Physical Properties in Paleogene Clastic Reservoir in the West Sag of the Beach Area,Liaohe Depression

作　　者：刘媛媛[1,2] 于炳松[1] 朱金富[1] 钟高明[1] 张林林[2] 

机构地区：[1]中国地质大学地质过程与矿产资源国家重点实验室,北京100083 [2]中国石油辽河油田分公司,辽宁盘锦124010

出　　处：《现代地质》2009年第4期731-738,共8页Geoscience

基　　金：辽河油田分公司辽河滩海地区储层与岩性地层圈闭识别与评价项目(JS14099-4)

摘　　要：辽河滩海西部凹陷古近系储层砂岩类型主要以长石岩屑砂岩、岩屑长石砂岩、岩屑砂岩及杂砂岩为主,为近源、多源沉积体系,砂岩成分成熟度及结构成熟度低。孔隙类型包括原生孔隙、次生孔隙及混合型孔隙。研究表明该区古近系储层成岩阶段处于早成岩B段至晚成岩A段,主要发育机械压实、胶结、溶解及交代等4种成岩作用。其中溶解作用为主要的建设性成岩作用,发育程度普遍较强。机械压实、胶结及交代等成岩作用为破坏性成岩作用,发育程度中等。储层物性随深度增加呈现有规律的变化,在1400-2600 m和2800-3400 m深度范围内,孔隙度和渗透率出现异常高值。成岩作用的强度和期次是影响储层孔隙发育的主控因素之一,该区的两个异常孔隙发育带是各种成岩作用综合的结果。其中第一异常孔隙发育带与有机质成熟有关,成岩环境为酸性;第二异常孔隙发育带则与碱性成岩作用有关,硅质组分的溶解对次生孔隙的形成及保存具有重大的贡献作用。The main lithological types are feldspathic lithic sandstone,lithic feldspar sandstone,lithic sandstone and greywacke with low compositional and textural maturities in the Paleogene reservoir in the west sag of the beach area,Liaohe Depression.The sedimentary environment is near-source and multi-source depositional system.The pore types are primary pores,secondary pores and compound pores.The physical properties alter regularly with the burial depth and the abnormal high values of porosity and permeability at the depth scale of 1,400 to 2,600 meters and 2,800 to 3,400 meters.The research infers that the diagenetic stage of this reservoir is from B substage of early diagenesis to A substage of late diagenesis and the primary types contain mechanic compaction,cementation,dissolution and metasomatism.In detail,the metasomatism is constructive with prevalence and strong degree,and the other three are detrimental with medium degree.The main controlling factors are the intensity and stages of diagenesis.These two abnormal porosity zones are attributable to the composite effects of various diagenesis activities.The first zone is related to the organic maturity in the acid diagenetic environment and the second one in the alkaline environment,in which the dissolution of silica components contribute the formation and reservation of secondary pores to a great degree.

关 键 词：古近系储层 成岩作用 物性 滩海西部凹陷 辽河坳陷 

分 类 号：TE122.2[石油与天然气工程—油气勘探]