Determination of Porosity and T2 Cut-Off using Nuclear Magnetic Resonance (NMR) Machine in Low Resistivity Low Contrast (LRLC) Reservoir

Conventional logs are very effective in determining the petrophysical
properties for normal reservoirs but in low resistivity pay reservoir it is really hard to
get an accurate results. Nuclear Magnetic Resonance (NMR) is a common tool
utilized in core analysis. NMR can reveal important information about pore structure,
fluid configuration and wettability. Since NMR works as a lithology-independent
tool, thus it is very useful in the low resistivity pay reservoirs to help determine the
petrophysical properties.
The main objectives of this study are to determine the NMR porosity from
transverse relaxation (T2) distribution curve and also to compute the T2 cut-off value
and hence distinguishing the clay bound water, capillary bound water and free fluids.
In the analysis of NMR data, several aspects of NMR technique have been
used such as are under T2 distribution to compute porosity and also determining the
intersection of fully saturated and desaturated at 100 psi curves to estimate the T2
cut-off. Analysis of the NMR data has helped to identify the porosity, T2 cut-off,
distinguish between bound and free water and also helps in finding the amount of
clay bound water.