Demagnetizer to Eliminate Residual Magnetization Produced by Nuclear Magnetic Resonance Logs

摘要

An apparatus and method is disclosed for measuring a parameter of an earth formation surrounding a wellbore. A Nuclear Magnetic Resonance (NMR) tool and at least one second tool are conveyed in the wellbore on a wireline, the NMR tool having a magnetic influence on a region of the wellbore. The magnetic influence of the NMR tool is removed from the region of the wellbore using a demagnetizing device. The parameter of the earth formation is measured using the at least one second tool. A second demagnetizing device may be used to remove the magnetic influence of the at least one second tool from the region of the wellbore.