鄂尔多斯盆地镇北油田延长组低渗透储层成因及油气运移特征  

Low permeability reservoirs genesis and petroleum migration of the Yanchang Formation,Zhenbei Oilfield,Ordos Basin

作　　者：王学军[1,2] 王志欣[2] 陈杰[3] 曾溅辉[2] 许晓凤[2] 

机构地区：[1]中国石化股份中原油田分公司勘探开发科学研究院,河南濮阳457001 [2]中国石油大学(北京)盆地与油藏研究中心,北京102249 [3]中国石油长庆油田分公司勘探开发研究院,陕西西安710021

出　　处：《油气地质与采收率》2010年第1期15-18,共4页Petroleum Geology and Recovery Efficiency

摘　　要：低渗透储层具有孔隙结构复杂和毛细管阻力大等特点,油气在其中运移的动力、路径以及运移方向是低渗透储层油气成藏研究的关键。以鄂尔多斯盆地镇北油田为例,通过岩石显微薄片分析、扫描电镜能谱分析、原油含氮化合物油气运移示踪分析、砂岩含油饱和度变化特征等,分析了延长组低渗透储层的成因、油气运聚时期的储层物性以及油气在低渗透储层中的运移特征。结果表明,该区延长组储层受沉积和成岩作用的影响在油气大规模运移之前就已经形成低渗透储层,岩石中存在的大量软颗粒以及特殊的同生软颗粒是形成低渗透储层的根本原因;油气侧向运移距离短,裂缝、微裂缝为主要运移通道,在异常压力作用下油气具有幕式快速运移的特征。Low permeability reservoirs have the characters of complex pore structure and high capillary resistance.The keys to the reservoir research are the driving force,migration channel and transportation direction.Taking Zhenbei oilfield of Ordos basin as the exam-ple-the genesisireservoir properties during the hydrocarbon accumulation and the transportation characteristics of low permeabil-ity reservoirs were researched,and by means of thin-section analysis,energy spectroscopy of scanning electronic microscope,hy-drocarbon migration tracer analysis of nitrogen compounds.and variation characteristics of oil saturation in sandstones.The result shows that reservoirs of Yanchang Formation in Ordos Basin had been converted to be low permeable prior to the massive oil mi-gration due to the sedimentation and diagenesis? and the low permeability was essentially caused by abundant soft grains and spe-cial contemporaneous soft grains in sandstones.The distance of petroleum lateral migration is short.and oil mainly migrates along fractures and micro-fractures.The petroleum migration is rapid and periodic under abnormal pressure.

关 键 词：低渗透储层 成因 运移特征 延长组 镇北油田 鄂尔多斯盆地 

分 类 号：TE112.2[石油与天然气工程—油气勘探]