“…The CT scan method is considered to be a nondestructive method to measure the cores' porosity, gas or oil saturation, and lithology characteristics within the cores (Siddiqui and Khamees, 2004;. The CT scan method has been widely used in petroleum engineering applications for describing the core porosity (Siddiqui et al, 2005), relative permeability (MacAllister et al, 1993), investigating the performance during core flooding experiments (London, et al, 2014), or other EOR processes (Kovscek et al, 2008;Simjoo et al, 2013;Tovar et al, 2014;. For this study, core plugs were scanned during the huff-n-puff tests to reflect the gas or oil saturation changes inside the core, and to help calculate the oil recovery in different stages.…”