Nanotechnology has already contributed significantly to advances in several industries, e.g. electronics, biomedical, aerospace, and more recently the energy industries. In particular, nanotechnology has the potential to pioneer changes in several areas of the oil and gas industry, such as exploration, drilling, production, enhanced-oil-recovery (EOR), and refining. For example, superparamagnetic nanoparticles that could act as contrast agents could be used to accurately determine the oil saturation distribution in a reservoir and help determine bypassed oils. Moreover, by correctly functionalizing the surface of the magnetic nanoparticles, colloidal suspensions of these nanoparticles that are stable at high temperatures and high salinities (oil-well conditions) can be prepared and could be co-injected with sweep and/or fracture fluids and their location determined and tracked over time by electromagnetic measurements. With this in mind, a study of the magnetic properties of ferrite nanoparticles with varying compositions (MFe2O4; M = Fe, Al) has been conducted to determine the magnetic responses of the various particles in order to evaluate the likelihood of using them as magnetic contrast agents in the oil and gas industry.