Transient Electromagnetic Dual Emitter

Abstract

The invention relates to a transient electromagnetic duality emitting device. The transient electromagnetic duality emitting device comprises a receiving coil and duality emitting coils, wherein the duality emitting coils are arranged at the upper end and the lower end of a fixed device respectively and are in mutual series connection, the receiving coil is fixed in the middle position of the fixed device, and the receiving coil is mutually perpendicular to the upper duality emitting coil and the lower duality emitting coil. The duality emitting coils are arranged at the two ends of the fixed device in a winding mode, the winding directions of the duality emitting coils are opposite, the distance between the duality emitting coils can be adjusted according to detection requirements, series connection circuits of the duality emitting coils are used for supplying electricity to the coils, and primary filed signals are stimulated. The coefficient of mutual induction of the transient electromagnetic duality emitting device is obtained to be zero according to the relation of the coefficient of mutual induction and the relative positions of the coils, the mutual inductance caused by current changes in a transmitting coil and the receiving coil can be effectively reduced, and the signal to noise ratio is improved. The duality emitting coils are adjustable, duality emitting is achieved, transient electromagnetic lateral propagation energy can be increased, and the lateral detection depth can be increased ultimately. The transient electromagnetic duality emitting device is simple in operation and can be operated by any constructor.

Description

technical field [0001] The invention relates to a transient electromagnetic dual emission technology, in particular to a transient electromagnetic dual emission device in a borehole. It is used in technical fields such as geophysical logging and engineering non-destructive testing. Background technique [0002] At present, underground engineering detection and underground disaster prevention and control are mainly carried out by means of drilling combined with geophysical exploration. The daily geological prediction of mine roadways and traffic tunnels requires a large number of horizontal drilling projects. A mining face of a high-gas mine requires tens of thousands of meters of gas drainage boreholes for drainage. The geological structure and disaster detection of mines also require a large number of Drilling works. The transient electromagnetic method is to use an ungrounded return line or a grounded line source to emit a pulsed magnetic field underground, and use a coi...

AI Technical Summary

Problems solved by technology

[0003] The existing transient electromagnetic method usually adopts the mode of one transmission and one reception or one transmission and multiple reception, and adopts the secondary field measurement method. The mutual inductance signal of the transmitting coil and the receiving coil is included in the transition process, so that the effective signal of the secondary field can be identified in the early period. It is difficult to extract and extract. If the signal-to-noise ratio of the early secondary field is improved, the traditional observation methods such as overlapping loops must be changed.

On the other hand, the traditional downhole transient electromagnetic method mainly solves the anomaly in front of the coil, and the excitation to the side is insufficient, which makes it extremely difficult to identify the lateral anomaly. receiving observation system device

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