特低-超低渗透砂岩储层微观孔喉特征与物性差异  

The Relationship between Micro-Pore Throat Characteristics and Physical Property Difference in an Extra-Ultra Low Permeability Sandstone Reservoir

作　　者：高辉[1] 孙卫[2] 费二战[3] 齐银[4] 李达5 

机构地区：[1]西安石油大学石油工程学院,陕西西安710065 [2]西北大学地质学系,陕西西安710069 [3]中国石油长庆油田分公司第三采油厂,宁夏银川750006 [4]中国石油长庆油田分公司超低渗透油藏研究中心,陕西西安710021

出　　处：《岩矿测试》2011年第2期244-250,共7页Rock and Mineral Analysis

基　　金：陕西省教育厅2010年科学研究计划资助(2010JK778);“十一五”国家科技支撑计划项目资助(2007BAB17B02)

摘　　要：为揭示特低-超低渗透砂岩储层微观孔隙结构与物性差异的关系,利用物性分析、铸体薄片、电镜扫描和高压压汞技术对鄂尔多斯盆地延长组3个典型的特低-超低渗透砂岩储层岩芯样品进行了实验测试。研究结果表明,特低-超低渗透砂岩储层喉道类型多样;但整体细小,对渗透率起主要贡献的较大喉道含量小是其物性较差的主要原因,同时微裂缝的发育也加剧了物性差异。统计对比发现,孔喉的分选系数在2.0～3.0,变异系数在0.15～0.3,对渗透率贡献相对较大。可见,储层物性是多种因素共同影响的综合反映,不同类型孔隙、喉道组成的储集空间,渗透率存在较大差异,物性差异正是孔喉特征差异的一种具体表现。In order to study the relationship between micro-pore throat characteristics and physical property difference,drill core samples of extra-ultra low permeability sandstone from a reservoir in the Yanchang group of the Ordos Basin were selected for physical property analysis,cast section,SEM and mercury penetration techniques.The results indicate that throat type in an extra-ultra low permeability sandstone reservoir is versatile and minute.The content of major throat which makes a dominant contribution to permeability is low,which is the main reason for poor physical property.Meanwhile,micro-cracks aggravate the difference in physical property.The distribution and variation coefficients range from 2.0 to 3.0 and 0.15 to 0.3 respectively,providing a major contribution to the permeability of sandstone.Physical property is the combined result of the mutual effect of multiple factors.Permeability presents large deviation when the reservoir space is composed of different pore throat types.

关 键 词：微观孔喉特征 物性差异 微观非均质性 特低-超低渗透砂岩储层 鄂尔多斯盆地 

分 类 号：TE122[石油与天然气工程—油气勘探]