基于岩石CT图像的碳酸盐岩三维孔隙组构的多重分形特征研究  

Multifractality of 3D pore structures of carbonate rocks based on CT images

作　　者：谢淑云[1] 何治亮[2] 钱一雄[2] 方海平[1] 张天付[1] 张殿伟[2] 沃玉进 鲍征宇[1] 

机构地区：[1]中国地质大学(武汉)地球科学学院,湖北武汉430074 [2]中国石油化工股份有限公司石油勘探开发研究院,北京100083

出　　处：《地质学刊》2015年第1期46-54,共9页Journal of Geology

基　　金：国家重大专项"大型油气田及煤层气开发"(2008ZX05005);国家"973计划"项目"中国早古生代海相碳酸盐岩层系大型油气田形成机理与分布规律"(2012CB214802)联合资助

摘　　要：碳酸盐岩微观孔隙的空间组构研究是储层性能研究的核心问题之一。近年来,基于二维图像进行碳酸盐岩孔隙空间组构研究的工作层出不穷,基于三维图像进行碳酸盐岩孔隙空间组构三维重建和基本统计特征表征的研究也引起了国内外的广泛关注。拟以四川盆地三叠系飞仙关组和震旦系毛田组碳酸盐岩为研究对象,通过三维高分辨率微纳米CT扫描,结合图像识别等计算技术,运用多重分形理论,对不同类型储层的孔隙在三维立体空间上的几何形态、非均质性与复杂度等特性进行定量表征,刻画了孔隙组构的空间展布规律。研究显示,2个样品孔隙组构在三维空间上分布不均一,具有明显的分形与多重分形分布特征;所得多重分形参数能定量刻画孔隙空间上大小孔隙的相对分异情况,能为孔渗性能提供参考。Spatial pore heterogeneity in carbonate rocks has long been regarded as a significant factor in the study of reservoir capability. In recent years,much attention has been paid to digital analysis of spatial pore microspaces in carbonate rocks by 2 dimensional images,and the reconstruction of 3D micro-pore networks and statistical representations of pore spaces have also aroused much concern.Taken the Triassic Feixianguan Fm. and Sinian Maotian Fm. carbonate rocks as examples,this study analyzed the heterogeneity of pore spaces in carbonate rocks based on digital high-resolution CT images acquired at various magnifications. Pore spaces were extracted and3 D visual presentation of the pore networks were reconstructed from the CT images using computer techniques. Pore irregularity of multifractal properties was further discussed with the method of moments. These results demonstrate that the multifractal method is effective for quantitatively characterizing the heterogeneity of pore spaces in carbonate rocks. It is found that there is a link between the multifractal parameters and the permeability of carbonate rocks under consideration,which can provide new indication for the quantitative assessment of oil-bearing potentials of rocks.

关 键 词：碳酸盐岩 CT图像 三维孔隙 多重分形 

分 类 号：P588.245[天文地球—岩石学] TE311[天文地球—地质学]