Figure 6: PCA of the glass bead sample. (A) PCA image; (B) Histogram of pore size distribution; and (C) photograph of the glass beads in a 15 mL falcon tube, where the blue line indicates the FOV.
Core Analysis:
MRI image sets of Berea sandstone, Indiana Limestone, and Madison Limestone, with pore spaces tighter than other cores previously reported in the literature [1,3,14], were collected using the ZTE pulse sequence. These images were processed and analyzed using the Mathematica notebook described previously. Figure 7 compares the three different core samples in their 3D reconstructions with filters applied. The yellow hue indicates the presence of water in the pore spaces. It is clear from Figure 7 that all three samples are saturated with water, as seen by the bright yellow hue throughout the cores. The Berea sandstone appears more homogeneous with even dispersal of both yellow (water) and red (solid material or space devoid of water) (Figure 7A and 7D). The Indiana Limestone core shows that higher water saturation occurs on the top and bottom of the core (Figure 7B and 7E). The Madison Limestone has larger and more disconnected pore spaces, exemplified by the more concentrated yellow hue wrapping through the core in Figure 7C and 7F.