| US 7,500,539 B1 | ||
| Method and apparatus of using crossed magnetic fields for measuring conductivity, permeability and porosity | ||
| Vitaly N. Dorovsky, Novosibirsk (Russian Federation); and Kholmatzhon Imomnazarov, Novosibirsk (Russian Federation) | ||
| Assigned to Baker Hughes Incorporated, Houston, Tex. (US) | ||
| Filed on Aug. 30, 2007, as Appl. No. 11/847,920. | ||
| Int. Cl. G01V 1/40 (2006.01) | ||
| U.S. Cl. 181—102 [181/105; 367/25] | 24 Claims |
| 1. A method of evaluating an earth formation, the method comprising:
(a) producing a static magnetic field in the formation from within a borehole;
(b) producing an oscillating magnetic field having a component substantially orthogonal to a direction of the static magnetic
field;
(c) measuring a velocity of a motion of a wall of the borehole resulting from the produced oscillating magnetic field; and
(d) using an amplitude of the measured velocity of motion, and two of the following three quantities: (A) an electrical conductivity
of the formation, (B) a porosity of the formation, and (C) a permeability of the formation, to estimate the third of said
three quantities.
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