摘要
陆相断陷湖盆扇三角洲沉积具有相变快、砂体接触关系复杂的特点。以南堡凹陷高76断块沙三1亚段为例,根据岩心、测井和生产动态等资料,分析断陷小湖盆扇三角洲前缘单砂体构型特征,建立扇三角洲前缘三维构型模式。结果表明:研究区扇三角洲前缘砂体发育水下分流河道、河口坝、溢岸及水下分流间湾4种沉积微相类型。单砂体侧向拼接主要有4种样式,即水下分流河道—水下分流河道拼接型、水下分流河道—河口坝拼接型、河口坝—河口坝拼接型、泥岩分隔型。垂向上,单层单砂体发育水下分流河道—河口坝“上河下坝”叠置、多期河道叠置及多期河口坝叠置3种样式。平面上,研究区扇三角洲前缘砂体呈条带状或交织条带状展布,交织条带状砂体由多个单一条带状的单砂体组成。扇三角洲河口坝较发育,位于河口坝的上部,下切河口坝,发育“河在坝上走”的模式。单一水下分流河道砂体厚度介于2.00~6.30 m,宽度介于57.65~499.20 m,平均宽厚比约为41∶1;单一河口坝砂体厚度介于2.26~9.60 m,宽度介于106.26~651.00 m,平均宽厚比约为73∶1;单一溢岸砂体厚度介于0.60~3.46 m,宽度介于40.08~136.35 m,平均宽厚比约为25∶1。单砂体接触关系不同是井间连通性差异的重要影响因素。该结果为南堡凹陷剩余油挖潜及优化开发方案提供参考。
The deposition of fan-delta in a small continental lacustrine rift basin is characterized by fast facies transformation and complex sandbody contact relationship.Taking the formation of subsection 1 of the third member of Shahejie of Gao-76 fault block in Nanpu Sag as the research object,the single sandbody architecture of fan-delta front reservoir is analyzed and the three-dimensional architecture model of fan-delta front in small lacustrine rift basin is established by using core,well logging and dynamic data.The results show that there are four types of sedimentary microfacies in fan-delta front:underwater distributary channel,mouth bar,overbank and underwater distributary bay.There are four types of lateral splicing of single sandbody in the study area:underwater distributary channel-underwater distributary channel splicing type,underwater distributary channel-mouth bar splicing type,mouth bar-mouth bar splicing type and mudstone separated type.And there are three vertical superposition types of single sandbody in the study area:underwater distributary channel-mouth bar sandbody superposition,multi-stage channel sandbody superposition and multi-stage mouth bar sandbody superposition.The sand body with interlacing strip in plane is composed of several single strip sand bodies.The sandbody thickness of single underwater distributary channel ranges from 2.00 m to 6.30 m.The width ranges from 57.65 m to 499.20 m,and the average width-thickness ratio is 41∶1.The sandbody thickness of single mouth bar ranges from 2.26 m to 9.60 m.The width ranges from 106.26 m to 651.00 m,and the average width-thickness ratio is 73∶1.The sandbody thickness of single overflowed sand body ranges from 0.60 m to 3.46 m.The width ranges from 40.08 m to 136.35 m,and the average width-thickness ratio is 25∶1.The contact relationship of single sand body is an important factor for the connectivity between wells.The results provide reference for tapping the potential of remaining oil and optimizing the development plan in this area.
作者
马立民
宋宝顺
余成林
张振宇
李庆
岳大力
MA Limin;SONG Baoshun;YU Chenglin;ZHANG Zhenyu;LI Qing;YUE Dali(Exploration and Development Research Institute of Jidong Oilfield Company,PetroChina,Tangshan,Hebei 063004,China;College of Geosciences,China University of Petroleum(Beijing),Beijing 102249,China)
出处
《东北石油大学学报》
CAS
北大核心
2023年第2期1-16,I0001,共17页
Journal of Northeast Petroleum University
基金
国家自然科学基金项目(41872107)。
关键词
断陷小湖盆
扇三角洲前缘
构型模式
单砂体
储层构型
南堡凹陷
rift lacustrine basin
fan-delta front
depositional model
single sandbody
reservoir architecture
Nanpu Sag
