安塞特低渗叠加砂岩单砂体剩余油分布机理与挖潜  

Mechanism and tapping potentialities of remaining oil distribution in single sand body of superposition sandstone of extra-low permeability reservoirs in Ansai

作　　者：刘新菊[1] 高月刚[1] 张洪军[1] 薛利娜 王学生[1] 

机构地区：[1]中国石油长庆油田分公司第一采油厂 [2]中国石油长庆油田分公司长庆科技工程有限公司

出　　处：《低渗透油气田》2015年第2期70-74,共5页

摘　　要：安塞特低渗透亿吨级整装油田主力油层长6_1^1-2。小层内部由4期河道叠加的单砂体组成，经过30年的注水开发，剖面动用不均，强水淹厚度不足15％。具有较大的挖潜能力。在大量的野外露头调查和检查井岩心观察与分析测试的基础上，利用加密井网测井资料开展单砂体构型解剖，结合生产动态资料和测试资料，分析小层内单砂体剖面动用状况，建立水驱规律与水淹模型，进行单砂体动用程度评价，有针对性地提出隔采、补孔压裂、重复压裂等措施方案。经过矿场数百口低产、低效、长关井实施与跟踪评价，平均单井日净增油量在1．0t以上，效果良好。这说明储层改造过程中纵向上裂缝延伸规模较小，没有在小层内单砂体之间穿层．搞清了单砂体之间剩余油分布的机理，明确了进一步挖潜的对象与思路，形成了安塞油田单砂体剩夺油动用的有效动用理论与技术．对今后类似的国内外特低渗多期河道叠加砂岩开发中后期剩余油挖潜具有一定的借鉴意义，，The small layers Chang6_1^1-2 of major reservoirs of the extra-low permeability Ansai Oilfield, as a unitary oilfield with tmn- dred-megaton-level productivity, are comprised of four-stage channel-superimposed single sand bodies. After 30 years of waterflood- ing, the producing injection profile is not uniform, with a strong flooded thickness of less than 15%. So the reservoirs have great ability to tap the potentialities. Based on a large number of outcrop survey, core observation and analysis and test from the inspection wells, configuration of the single sand body is deep analyzed by use of the logging data of the infill-drilling well pattern. Combined with pro- duction performance data and test data, the authors analyze the status of producing reserves of single sand-body profiles in the small layers, establish a waterflooding law and flooded model, evaluate the percentage of the producing reserves in the single sand-body, and put torward pertinently the measures and schemes such as alternating-layer oil recovery, fracturing by re-perforating, repeated lractu- ring and other measures. After long shut-in and follow-up assessment of hundreds of low-yielding, inefficient wells, the average net in- crease of oil production per well is 1.0 t/d or more, and with good effect. This shows that during the reservoir stimulation process, the fracture, extension in the longitudinal direction is small, does not pass through a small layer between the single sand-bodies within the small layers. The meehanism of remaining oil distribution between the single sand-bodies is found out. Objects and ideas of further tap- ping the potentialities are made explicit. Therefore, the authors form an effective theory and technology of producing reserves ＇about remai- ning oil in single sand bodies of Ansai oilfield. It has certain reference significance for the future similar extra-low permeability multistage channel-superimposed sandstone development in the mid-to-late period to tap the potentialities in the remaining oil at home and

关 键 词：安塞油田 特低渗透储层 叠加砂岩 单砂体 剩余油 

分 类 号：TE33[石油与天然气工程—油气田开发工程]