Nuclear Magnetic Resonance
mud logging technology (NMR mud logging) is a new mud logging technology.
Mainly applies the CPMG(Carr-Purcell-Meiboom-Gill)pulse sequence to measure transverse relaxation time (T2)
of the fluid. NMR mud logging can measure drill cutting, core and sidewall core
in the well site, also according to the experiment results, the sample type and
size has little effect to analysis result. Through NMR logging, we can obtain
several petrophysical parameters such as total porosity, effective porosity,
permeability, oil saturation, water saturation, movable fluid saturation,
movable oil saturation, movable water saturation, irreducible fluid saturation,
irreducible oil saturation, irreducible water saturation, pore size and
distribution in rock samples, etc. NMR mud logging has been used nearly 10 years in China, Sudan,
Kazakhstan, etc. it plays an important role in the interpretation and
evaluation of reservoir and its fluids.