Fluid Typing

It is possible that different fluids, such as heavy oils and partially bound water, may exhibit similar T2 values, which makes it difficult to identify which fluid is which using a standard T2 distribution alone. If two fluids have similar T2 values, they are unlikely to have similar diffusion characteristics, so a measurement that collects both T2 and diffusion data should be able to separate the fluid types. The result is a two-dimensional data map illustrating the relative proportions of the different fluid types in the sample.

For unconventional samples diffusion measurements often do not work, so we do T1-T2 2D mapping, which is measuring NMR relaxation, T2, at different T1values. The ratio of T1 to T2 changes based on the viscosity. This experiment also helps quantify the type of hydrogen (water, oil, clay or organic) present in the sample. Signals with T1/T2 ratios between 1 and 2 are likely due to low viscosity fluid, like water (bound or free). Higher ratios are from more solid like components such as bitumen.