Saturation-dependent nuclear magnetic resonance relaxation of fluids confined inside porous media with micrometer-sized pores.

In the present study, we investigate the relationship between the relaxation rate and the filling factor in partially saturated porous media. The filling fluids are polar (water, acetone) and nonpolar (cyclohexane, hexane). The porous sample is a silica glass (Vitrapor#5) with the nominal mean pore size of d = 1 µm ( ± 0.6 µm). All nuclear magnetic resonance relaxation experiments are performed at 20 °C using a NMR instrument operable at 20 MHz proton resonance frequency. The experimental results are compared with a two-phase exchange model providing us information on the strength of surface relaxation and fluid distribution inside pores. These results will affect the NMR estimations about fluid content of porous media.