Microscopic Features of Mudstone Based on SEM Images

Microstructure features have a significant effect on the engineering properties of geomaterials. In the current study, the images of the mudstone samples were obtained using the Scanning Electron Microscopy (SEM) technique. After converted the original images into the grayscale and binary ones, the Canny edge detection technique was utilized to detect the particle edges and compute the characteristic shape parameters of the particles in the SEM images, including the eccentricity, flat circular degree, circular degree, discrete index, radius of inscribe circle. The analysis of correlation between these shape parameters was thereafter performed. All of the above processings was implemented using the MATLAB platform. It shows that some parameters, such as eccentricity and anisotropic rate, had a great correlation; and other parameters, such as perimeter and discrete index, had a good correlation; some parameters, such as anisotropic rate and area, had no correlation. The methods presented herein may be referable in investigating the structural features and deformation/failure mechanism of the mudstones in various scales.