Measurements and analysis of fluid saturation-dependent NMR relaxation and linebroadening in porous media.

NMR T1, T2 and spectral linewidth measurements were conducted in rock samples with different saturations obtained by drainage experiments. Saturation dependent T1 was found to follow a power-law relationship and the inverse of linewidth to follow a linear dependence with saturation. These phenomena can be explained by considering that the fluids are distributed in different sized pores for different saturation states. A method is proposed for calculating wetting phase relative permeabilities using T1 data at various saturations.