| 摘要 |
An apparatus and method is disclosed for induction logging of electrical properties of earth formations that operates at low frequencies while remaining resistant to skin effect and maintaining mutual balancing. The apparatus includes a plurality of transmitter coils 210-270 that are at a plurality of distances from a measure point 220 located at an end of the apparatus, and a receiver coil array 228 coupled to receive induced voltages resulting from currents induced in the earth formations by one or more transmitters of the plurality of transmitter coils, wherein the common measure point is located within the receiver coil array, and wherein one or more of the plurality of distances from the measure point are determined according to a function of one or more frequencies associated with one or more transmitters of the plurality of transmitters. |
