DOWNHOLE MONITORING OF FLUIDS USING NUCLEAR MAGNETIC RESONANCE

摘要

A downhole logging tool, in an illustrative embodiment, includes an NMR measurement system with surface NMR microcoils located on an outer surface of the downhole logging tool. Each surface NMR microcoil has a central axis and is distributed around the outer surface of the logging tool with the surface NMR microcoil central axis perpendicular to the longitudinal axis of the logging tool. The NMR measurement system may have a central flow line in fluid communication with the drilling fluid. Additional surface NMR microcoils or a flow line microcoil may be disposed circumferentially around the central flow line with the surface NMR microcoil central axis and the flow line NMR microcoil central axis, respectively, perpendicular and parallel to the central flow line longitudinal axis. The NMR measurement system may include a bypass flow line in fluid communication with fluid in the wellbore annulus and/or the drill pipe.