Computing Rock Physics Trends Using Sandstone Micro-CT Images And Digital Mineral Precipitation Available to Purchase

Modern imaging technology provides high-resolution x-ray computer tomographies of Fontainebleau sandstone on the microscale. The 3-D images of the true rock microgeometries allow hydraulic and elastic rock properties to be estimated accurately and efficiently with the help of digital rock physics. Furthermore, image processing algorithms allow to add an additional material phase to the pore space, thus making it possible to compute porosity-permeability trends which reflect the effects of mineral precipitation. Based on the distance of individual pore voxels to the grain walls, three different precipitation patterns are generated. It turns out that at permeabilities around 0.15, the permeability is insensitive to the distribution of precipitated solid material in the pore space. At low porosities close to the percolation threshold, material in small pores may close flowpaths and may create a significant amount of disconnected porosity, which effectively reduces hydraulic permeability. The computer simulations are in agreement with laboratory measurement of permeability changes associated with salt precipitation.