摘要 玛湖西部斜坡区二叠系乌尔禾组发育厚层砂砾岩储层,且油气储量巨大,但目前对于该套砂砾岩储层成因的认识尚不统一。在岩心、测井和地震资料分析的基础上,认为该区乌尔禾组发育冲积扇相和辫状河三角洲相。冲积扇分布在乌尔禾组下部,由于扇体不断前积,形成进积型冲积扇,纵向上沉积物粒度呈反韵律。辫状河三角洲相主要分布在乌尔禾组上部,划分为平原和前缘亚相,其中平原亚相以数层煤层和碳质泥岩为特征。乌尔禾组沉积过程为湖平面不断上升的过程,表现为由下部冲积扇相向上变为辫状河三角洲相。沉积相类型对储层物性具明显的控制作用,辫状河三角洲前缘储层物性较好,冲积扇储层物性较差。 The Permian Wuerhe formation in the western slope area of Mahu lake has developed thick glutenite reservoir with huge oil and gas reserves.However,the understanding of the origin of the reservoir is not unified.based on the analysis of core,logging and seismic data,it is considered that alluvial fan facies and braided river delta facies are developed in Wuerhe formation.Alluvial fans are distributed in the lower part of the Wuerhe formation.Because of the continuous progradation of the fan body,the alluvial fan is of progradational type,and the grain size of the sediment presents an inverse rhythm in the longitudinal direction.Braided river delta facies is mainly distributed in the upper part of Wuerhe formation,which is divided into plain and front subfacies.Plain subfacies are characterized by several coal seams and carbonaceous mudstone.The sedimentary process of Wuerhe formation is a process of rising lake level,which shows that the lower alluvial fan facies changes upward into braided river delta facies.The type of sedimentary facies has an obvious control on the physical properties of the reservoir.The reservoir physical properties of braided river delta front are better than those of alluvial fan reservoir.
机构地区 中国石油新疆油田分公司采油二厂
出处 《新疆地质》 CAS CSCD 北大核心 2021年第1期99-103,共5页 Xinjiang Geology
基金 准噶尔盆地油藏富集规律及勘探技术研究与应用(2017E-0401)项目资助。
关键词 玛湖西部斜坡区 乌尔禾组 冲击扇 储层 湖平面变化 Western slope area of Mahu Lake Wuerhe formation Impact fan Reservoir Lake level change
