| 摘要 |
A method for measuring in situ formation fluid flow utilizing an NMR logging while drilling tool is disposed in the borehole, a modified saturation recovery or time of flight angiography pulse sequence is utilized to tag spins in the formation, at least two measurements are made of the tagged spins as they propagate toward the borehole in the under-balanced environment, allowing a determination of fluid velocity, from which permeability may be determined. Techniques are disclosed to perform the method in both an over-balanced and under-balanced environment. |
