Patent ID: 6051973
Filing Date: 2000-04-18
Classification: G01N,G01V

Abstract:
A method for determination of petrophysical properties of a geologic formation using an NMR logging tool, comprising the steps of:(a) generating at least one radio frequency pulse covering a relatively wide range of frequencies to saturate nuclear magnetization in a cylindrical volume around the tool;(b) transmitting a readout pulse sequence at a frequency near the center of the range of covered frequencies, the readout pulse sequence following a predetermined wait time after the saturation pulse;(c) receiving at least one NMR echo corresponding to the readout pulse sequence;(d) repeating steps (a), (b) and (c) one or more times for a different wait time to produce a plurality of data points on a T1 relaxation curve; and(e) processing the produced T1 relaxation curve to derive petrophysical properties of the formation.