PROBE OF ELECTROMAGNET LOGGING Russian patent published in 2010 - IPC G01V3/28 

FIELD: mining.

SUBSTANCE: probe comprises generator coil, near and far receiving coils located from the generator one at the distances z₁ and z₂, accordingly, and having magnetic torques M₁ and M₂, accordingly, so that Near and far receiving coils have identical number n of turns and arranged with diameters D₁ and D₂, accordingly, besides Length of winding of far receiving coil is identified by ratio where L is inductance (in microhenry) of near receiving coil. Near and far receiving coils are wound by wires with diameters d₁ and d₂, accordingly, besides

EFFECT: increased accuracy of measurements due to equality of impedances of receiving probe coils.