特低渗砂岩储层微观孔喉特征的定量表征  

Quantitative Characterization of Micro-pore Throat Characteristics in Ultra-low Permeability Sandstone Reservoir

作　　者：高辉[1] 孙卫[2] 

机构地区：[1]西安石油大学石油工程学院,西安710065 [2]西北大学大陆动力学国家重点实验室,西安710069

出　　处：《地质科技情报》2010年第4期67-72,共6页Geological Science and Technology Information

基　　金：国家重点基础研究发展计划"973"项目(2003CB214600);"十一五"国家科技支撑计划(2007BAB17B02)

摘　　要：以鄂尔多斯盆地延长组特低渗砂岩储层样品的恒速压汞实验结果为基础，对该类储层的微观孔喉特征进行了定量表征。结果表明，样品喉道差异较大，当渗透率小于1×10^-3μm^2时，喉道峰值半径、平均喉道半径均小于1μm，主流喉道半径变化幅度较小；当渗透率大于1×10^-3μm^2时，平均喉道半径大于1μm，喉道峰值半径、主流喉道半径变化幅度明显增大，大喉道所占比例及其对渗透率的贡献增大。样品的孔隙差别不大，主要分布于100-200μm范围内；孔喉半径比分布范围大，介于10～1000之间。样品渗透率越大，有效孔隙、喉道发育程度越好。渗透率不同，孔隙、喉道毛细管曲线对，息体毛细管压力曲线的影响程度也不同。Micro-pore throat characteristics are characterized quantitatively on the basis of laboratory findings of constant rate mercury penetration in ultra-low permeability sandstone reservoir samples of Yanchang Formation, Ordos Basin. The results show that throat changes greatly, when permeability is less than 1×10^-3μm^2 , peak value radius of throat and average throat radius are both less than 1 μm, with a minor variation range of the main throat. When the permeability is greater than 1×10^-3μm^2, average throat radius is greater than 1 μm, with an apparent increase in the variation range of throat peak value radius and the main throat, while the content of large throat, leading to the greater contribution to permeability. The pores of the samples are of negligible difference and are mainly distributed in 100-200 μm. While the pore throat ratio varies greatly, with a distributes within 10--1 000. It is found that higher permeability favors the effective pores and throat development and that with different permeability, the pore throat capillary curve exerts a varying effect on the total capillary curve .

关 键 词：微观孔喉特征 定量表征 储层品质 特低渗砂岩储层 鄂尔多斯盆地 

分 类 号：P618.130.2[天文地球—矿床学]