摘要
根据岩心照片、铸体薄片、扫描电镜和常规物性分析等资料,结合测井解释成果,从油源特征、沉积充填及砂体展布、储层物性及成岩作用、封盖保存条件等方面开展鄂尔多斯盆地直罗油田长8段油层组油气成藏条件研究。结果表明:直罗油田长7段有机质丰度高、类型好,且都达到成熟的热演化阶段,为研究区长8段油藏提供了充足的油源保障。研究区在宽缓西倾单斜背景下发育复合小型鼻状构造。长8段以三角洲前缘亚相为主,发育水下分流河道和河口坝,形成有利的沉积微相。长7段广泛发育的泥岩、致密粉砂岩、粉砂质泥岩构成该区良好的盖层。储层的有利相带、低幅度构造、储层特征共同控制研究区长8段的油气富集,且含油富集区主要受控于低幅度构造背景。
Based on some data from core, cast thin section, SEM identification, and conventional property property, the reservoir-forming conditions of Chang 8 Member, Zhiluo oilfield in Ordos Basin, were studied in terms of source, sedimentary filling, sandbody distribution, diagenesis, and caprock. Results show that(1) Chang 7 Member has much organic matter with high abundance, reaching a stage of mature thermal evolution, which can provide sufficient oil source for Chang 8 Member;(2) in the study area, a compound and small nosed structure is developed under a wide and gentle monocline;(3) the deltaic frontal subfacies are dominated in Chang 8 Member,which both underwater distributary channel and mouth bar are developed to form favorable sedimentary microfacies;(4) the mudstone, tight silitstone, and silty mudstone widely developed in Chang 7 Member are the better caprock;(5) favorable facies belt, low-amplitude structure, and reservoir characteristics are the main factors to control oil and gas accumulation of Chang 8 Member; and(6) oil accumulation areas are mainly affected by low-amplitude structure.
出处
《天然气勘探与开发》
2015年第1期16-21,3-4,共6页
Natural Gas Exploration and Development
基金
国家自然科学基金项目(41173035)"鄂尔多斯盆地下古生界低丰度海相烃源岩中有机酸(盐)生烃潜力评价"资助
关键词
油源条件
储层特征
油气成藏
直罗油田
source condition,reservoir characteristics,reservoir forming,Zhiluo oilfield
