核磁共振技术在特低渗砂岩微观孔隙结构评价中的应用  

Application of NMR technique in evaluation of micro-pore structure in extra-low permeability sandstone

作　　者：高辉[1] 孙卫[2] 田育红[3] 任国富[4] 路勇[3] 

机构地区：[1]西安石油大学石油工程学院,西安710065 [2]西北大学地质学系,西安710069 [3]中国石油长庆油田公司第三采油厂,银川750006 [4]中国石油长庆油田分公司油气工艺技术研究院,西安710021

出　　处：《地球物理学进展》2011年第1期294-299,共6页Progress in Geophysics

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

摘　　要：特低渗透砂岩储层微观孔隙结构变化复杂,且随机性强,利用核磁共振技术对取自鄂尔多斯盆地延长组的特低渗砂岩样品进行了测试分析.结果表明,实验样品的T_2截止值小,T_2谱分布表现出双峰态;可动流体参数差异较大,主要受孔隙(尤其是次生孔隙)的发育和连通程度、微裂缝的发育程度、粘土矿物含量及其赋存形式、孔隙的比表面大小及重结晶程度的影响.可动流体参数的变化可以较好地反映特低渗砂岩储层微观孔隙结构的变化特征,这也说明了利用可动流体参数来综合评价微观孔隙结构的合理性.Micro-pore structure of extra-low permeability sandstone reservoir varies complicatedly and has strong randomness. The extra-low permeability sandstone samples of Yanchang group in Ordos basin are tested with NMR technique. The results show that T2 cutoff value is little, T2 patterns present double peak shape. Difference of movable fluid parameters is major, which are affected by development and connectivity of pore （especially secondary pore）, growth degree of microcrack, content and occurrence form of clay mineral, surface to volume ratio of pore and recrystallization degree. Movable fluid parameters can fully reflect the variation characteristics of micro-pore structure in extra-low permeability sandstone reservoir, which also demonstrates that it is rational to evaluate the micro-pore structure comprehensively through movable fluid parameter.

关 键 词：核磁共振技术 可动流体 微观孔隙结构 特低渗砂岩储层 鄂尔多斯盆地 

分 类 号：P631[天文地球—地质矿产勘探]