为了解决辫状河单河道砂体接触类型及控制因素不清等问题,采用野外辫状河露头剖面观察实测的方法,并结合钻井和地震资料,对辫状河单期河道砂体接触关系进行综合分析.结果表明:辫状河砂体接触关系可以分为3类,包括侵蚀接触型、局部接触型和不接触型.这3种类型砂体在分布形式、泥岩夹层发育程度、储集物性和含油气性差异等方面均具有明显的不同.沉积相带对河道砂体接触关系具有控制作用.近源砾质辫状河沉积地形坡度较陡,水体能量高,河道砂体接触关系以侵蚀接触型为主;远源砾质辫状河道砂体接触关系以局部接触型为主;砂质辫状河道砂体接触关系以不接触型为主.基准面升降变化对河道砂体接触关系具有一定影响,当va与vs的比值较低时,河道砂体接触关系以侵蚀接触型为主;当va与vs的比值中等时,河道砂体以局部接触型为主;当va与vs的比值较高时,河道砂体接触关系以不接触型为主.研究结果对指导油田开发阶段井网部署和提高采收率均具有指导作用.%The contact type and controlling factors of single channel sand body in braided river are not clear.Accor-ding to the observation and analysis of the braided river outcrop profile in the field,combined with the drilling and seismic data,the contact relationship of the braided river single channel sand body was studied synthetically. The results show that the contact relationship of braided river sand body can be divided into three types,including the complete contact type,local contact type and non-contact type.These three types of sand bodies are obviously different in sand body distribution,mudstone interlayer,reservoir properties and oil-bearing property.The sedi-mentary facies has obvious control effect on the contact relationship between the river sand bodies.The geologic slope of the near-grained braided river sedimentary facies is also steep,the water body energy is high,and the contact relationship of the river sand body is dominated by the complete contact type.The contact relationship be-tween the sand bodies of the far-grained braided river sedimentary facies is dominated by local contact type.Sandy braided river sand body is mainly non-contact type.When the va/vsratio is low,the channel sand body is dominated by the complete contact type,when the va/vsratio is moderate,the channel sand body is dominated by the local con-tact type;and when the va/vsratio is high,the channel sand body is dominated by non-contact type.The research result is helpful for guiding the deployment and improvement of oil recovery in oilfield development stage.
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