MICROSCOPIC ARRANGEMENT OF OIL AND WATER IN SANDSTONE BY NMR RELAXATION-TIMES AND NMR IMAGING

The distribution and arrangement of dodecane for various immiscible deuterium oxide/dodecane saturations in natural sandstone rocks has been investigated by H-1 NMR and MRI at 0.1 T. Porosity and saturation can be readily measured to 1% accuracy, with a 1 mm resolution. In particular, we have examined the sensitivity to surface wettability. While the dodecane longitudinal relaxation is insensitive to wettability and saturation, detailed analysis shows that dodecane transverse relaxation can provide information on surface wettability and fluid distribution at a microscopic scale, through the sensitivity of transverse relaxation to magnetic field inhomogeneity.