Visualization of 2D diffusion phenomena in rock by means of X-ray CT

Sato, Akira*; Fukahori, Daisuke*; Sugawara, Katsuhiko*; Sawada, Atsushi ; Takebe, Atsuji*

The two dimensional (2D) diffusion tests with the rock sample which has single plane crack were conducted, and the diffusion of non-sorbing tracer from the crack to rock matrix is visualized by X-ray CT in this study. It was found that the increment of CT value due to the 2D diffusion of the dense tracer from crack surface to the matrix of rock sample was observed. It was also found that the application of image processing techniques makes it possible to obtain the clear image data and that the precious analysis of diffusion phenomena becomes possible. The numerical simulation was also conducted in order to verify the experimental results. The results of 2D diffusion tests show good agreement with the numerical results, and the applicability of X-ray CT to the analysis of diffusion phenomena in a rock sample was verified together with the necessary image processing techniques.