中—低丰度气藏盖层的空间分布及封闭特征  

Space distribution and sealing characteristics of cap-rock of medium-low abundance gas fields in China

作　　者：陈默[1,2] 王璐[3] 冯金义[4] 王少波[4] 孔令江[4] 赵永峰[4] 

机构地区：[1]东北石油大学CNPC断裂控藏实验室,黑龙江大庆163318 [2]中国石油大庆油田有限责任公司第一采油厂,黑龙江大庆163000 [3]中国石油大庆油田有限责任公司第六采油厂,黑龙江大庆163000 [4]中国石油大港油田公司勘探开发研究院,天津300280

出　　处：《断块油气田》2016年第1期31-35,共5页Fault-Block Oil & Gas Field

基　　金：国家科技重大专项课题"中西部重点前陆盆地断裂控藏机制与油气分布"(2011ZX05003-001);中国石油科技创新基金项目课题"碳酸盐岩内断裂带内部结构及油气运移和封闭"(2012D-5006-0107);教育部科学技术研究重点项目"碳酸盐岩内断裂带内部结构及对油气运移与封闭的控制"(212041)

摘　　要：文中以四川盆地中部气田为重点解剖对象,在全面分析中—低丰度气田盖层发育特征基础上,系统分析了中—低丰度气田盖层发育特征、封闭能力及对天然气分布的控制作用。研究表明,我国中—低丰度气田盖层以泥质岩为主,单层厚度小,横向连续性差,分为分隔层、局部性盖层和区域性盖层3级。盖层排替压力较低,普遍小于5 MPa,但由于气田主要分布在凹陷区,地层倾角缓,较小的排替压力可以使天然气大面积成藏。盖层总体表现为3级封盖模式:分隔层直接封闭,局部性盖层封隔,区域性盖层总控。气藏在分布上表现为大面积连片。Based on the overall statistics of cap-rock development characteristics in Chinese medium-low abundance gas fields,taken the gas field in the central of Sichuan Basin as the key research object, cap-rock development characteristics, sealing ability and control action of the gas distribution in Chinese medium -low abundance gas fields are analyzed systemically. Research shows that Chinese medium-low abundance gas field cap-rocks are dominated by mudstone, small thickness of monolayer, poor lateral reservoir continuity, which are divided into three parts, separation layers, localized cap-rock and regional cap-rock. The displacement pressure of cap-rock is low, generally less than 5 MPa. Because gas fields are located mainly in depressed area with slow strata dip, smaller displacement pressure can cause wide gas reservoir-forming. In total, cap-rock shows three-part-sealing mode： direct separation layers sealing, localized cap-rock sealing, regional cap-rock overhead control, the gas reservoir is generally distributed in large area.

关 键 词：中—低丰度 盖层 天然气 大面积成藏 封闭特征 

分 类 号：TE122.25[石油与天然气工程—油气勘探]