Scholarlink

<p>Clay content (the volume fraction, <i>V</i>sh) affects not only the structural characteristics of high-porosity sandstone but also the types and internal structures of deformation bands. To investigate the influence of clay content on the structures of deformation bands, in this study, high-porosity artificial sandstone with clay contents ranging from 5 to 25% was used as the research object. A self-developed “annular shearing device” was used to carry out ring-shear tests. The experimental results were analyzed through thin section observation, image analysis, micro/nano-CT scanning, and permeability testing processes to quantitatively characterize the induced microstructural and porosity–permeability changes. The test results revealed that as the clay content increased, the average width of the cataclastic band gradually decreased, the degree of grain fragmentation decreased, the porosity decreased, and the permeability decreased by 2 ~ 3 orders of magnitude compared with that of the host rock. This study reveals the dual role of clay minerals in the evolution trends of the cataclastic bands of high-porosity sandstone. On the one hand, they weaken grain fracturing through lubrication and limit the band width; on the other hand, they reduce the degree of permeability through pore filling.</p>

错误：搜索内容不能为空，请输入英文关键词
错误：关键词超出字数限制，请精简
高级检索

Structural Characteristics of Cataclastic Bands in High-Porosity Sandstone Under Clay Content Constraints: Inspiration from Ring-Shear Tests

  • 期刊论文

  • 发表日期：

    2026年6月25日

查看全文
  • Tianye Li,
  • Haixue Wang,
  • Zhida Liu,
  • Nan Jia,
  • Xianqiang Song,
  • Peng Xu

摘要

Clay content (the volume fraction, Vsh) affects not only the structural characteristics of high-porosity sandstone but also the types and internal structures of deformation bands. To investigate the influence of clay content on the structures of deformation bands, in this study, high-porosity artificial sandstone with clay contents ranging from 5 to 25% was used as the research object. A self-developed “annular shearing device” was used to carry out ring-shear tests. The experimental results were analyzed through thin section observation, image analysis, micro/nano-CT scanning, and permeability testing processes to quantitatively characterize the induced microstructural and porosity–permeability changes. The test results revealed that as the clay content increased, the average width of the cataclastic band gradually decreased, the degree of grain fragmentation decreased, the porosity decreased, and the permeability decreased by 2 ~ 3 orders of magnitude compared with that of the host rock. This study reveals the dual role of clay minerals in the evolution trends of the cataclastic bands of high-porosity sandstone. On the one hand, they weaken grain fracturing through lubrication and limit the band width; on the other hand, they reduce the degree of permeability through pore filling.