METHOD AND APPARATUS FOR USING FIELD GRADIENT PULSE NMR MEASUREMENTS TO DETERMINE FLUID PROPERTIES IN A WELL DIAGRAM TOOL BY FLUID SAMPLING

摘要

P A method for determining a property of a formation fluid includes acquiring a series of nuclear magnetic resonance (NMR) measurements of a fluid sample using a pulse sequence that includes pulses of pulsed field gradient to encode the scattering information, wherein each NMR measurement of the series is acquired with a different value than a pulsed field gradient pulse parameter to produce a different scattering effect, according to which the acquisition is performed in a formation fluid sampling tool in a borehole; inverting the NMR measurement series to produce a distribution function that associates the diffusion properties of the fluid sample with an NMR property of the fluid sample; and determining the property of the formation fluid from the distribution function. / P