The Application of Monochromatic Energies to Investigate Multiphase Porous Media Systems using Synchrotron X-ray Tomography

X-ray computed tomography (CT) is becoming a useful tool for nondestructive imaging of many geoenvironmental and geotechnical systems. Conventional X-ray CT systems typically utilize a polychromatic X-ray beam. While providing a high throughput of photons, the use of polychromatic energy can make quantifying material concentrations, densities or composition very difficult or impossible without appropriate standards. Synchrotron X-rays have an extremely small angular divergence, thus permitting spatial resolution that is only limited by the optical components of the system. In addition, the ability to tune to a monochromatic X-ray energy allows better phase contrast by reducing beam hardening and allowing for elemental discrimination. In this work we will show how monochromatic energy can be used to provide high-quality images allowing for phase separation several different porous media systems thus improving our ability to quantify a range of processes and phenomena.