WO2022166457A1

WO2022166457A1 - Borehole transient electromagnetic radial long-range detection and observation system and method

Info

Publication number: WO2022166457A1
Application number: PCT/CN2021/140957
Authority: WO
Inventors: 范涛; 李萍; 赵睿; 刘磊; 刘柏根; 李渊; 燕斌; 赵兆
Original assignee: 中煤科工集团西安研究院有限公司
Priority date: 2021-02-04
Filing date: 2021-12-23
Publication date: 2022-08-11
Also published as: AU2021426683A1; CN112946764A; CN112946764B

Abstract

A borehole transient electromagnetic radial long-range detection and observation system. The system comprises two three-component transceiving probes and a control probe, which is arranged between the two three-component transceiving probes, wherein each of the three-component transceiving probes comprises an outer framework; a transmitting coil is wound outside the outer framework; a first inner framework, a central inner framework and a second inner framework are successively arranged in the outer framework in an axial direction; a ferrite core is placed in the central inner framework, horizontal-component receiving coils in X and Y directions are respectively wound outside the central inner framework in a long edge direction; ferrite cores are placed in both the first inner framework and the second inner framework, and receiving coils in a Z direction are respectively wound outside the first inner framework and the second inner framework; and the probe parameters of the two three-component transceiving probes are different. Further disclosed are a borehole transient electromagnetic radial long-range detection and observation method and a method for processing data of borehole transient electromagnetic radial long-range detection and observation.

Description

Borehole transient electromagnetic radial long-distance detection and observation system and method

technical field

The invention belongs to the technical field of geophysical exploration, and relates to an in-hole transient electromagnetic observation system and method capable of detecting low-resistance geological anomalies (such as hidden water hazards) with a relatively long radial distance (≥30m) in the borehole.

Background technique

Coal mine accidents mostly occur during tunnel excavation, and water inrush accident is one of the major disasters. In order to ensure safe and rapid tunnel excavation, the mine side pays great attention to the hidden disaster-causing factors in the unexcavated area. In addition, coalbed methane hydraulic fracturing and floor grouting The detection of the transformation effect is also the focus of coal mines, and these problems can be solved by the use of borehole transient electromagnetic detection. In recent years, with the development of transient electromagnetic detection technology for underground boreholes in coal mines, the detection accuracy of low-resistance geological anomalies (especially the threat of water hazards) in the radial direction of boreholes has reached a high level, but the radial detection distance has been limited by the In the case of good geological conditions, radial detection of 30m is already the limit. This distance cannot well meet the needs of fracturing and grouting, because fracturing and grouting drilling hope that the hole spacing should be as large as possible, so To reduce costs, in order to ensure that the transient electromagnetic detection range of boreholes is not completely covered by blind spots and has certain overlapping sections, the current requirement is that the distance between boreholes should not be greater than 40m or 50m, which is smaller than the mine expects. At the same time, the radial detection distance of 30m is only barely sufficient for the advance detection of the roadway according to the safety regulations, there is no margin, and there is a need to increase.

To improve the radial detection distance, it is necessary to measure signals with longer time, which means that the transmission energy and signal receiving capability must be increased to improve the quality of late signal detection. Generally, the size of the transmitting coil, the number of turns of the transmitting coil and the The current intensity, increasing the number of turns of the receiving coil, and increasing the length of the receiving magnetic core, etc., but due to the small device in the drilling, any increase of a parameter will significantly increase the inductance of the device, resulting in the saturation of the early signal, and the greater the parameter increases. The longer the polysaturated section, the more geological information is lost in the radially closer range of the borehole.

In order to solve this problem, the present invention proposes a borehole transient electromagnetic observation system using a combination of two sets of three-component transceiver devices, respectively setting different device parameters, and designing a unique three-component coil arrangement to ensure comprehensive detection of the borehole diameter. Geoelectricity information to near and far.

SUMMARY OF THE INVENTION

Aiming at the defects and deficiencies in the prior art, the present invention provides a drilling transient electromagnetic radial long-distance detection and observation system and method, so as to solve the problems in the prior art that it is difficult to increase the radial detection distance.

To achieve the above object, the present invention adopts the following technical scheme:

A three-component transceiver probe includes an outer skeleton, a transmitting coil is wound outside the outer skeleton, and the axis line of the transmitting coil is the central axis of the outer skeleton; and also includes a first inner skeleton, a central inner skeleton and a second inner skeleton arranged in the outer skeleton in sequence. Two inner skeletons; a ferrite core is placed in the central inner skeleton and a horizontal component receiving coil in the X direction and a horizontal component receiving coil in the Y direction are wound on the outside of the central inner skeleton. The ferrite cores are placed inside and the Z-direction receiving coils are respectively wound outside the first inner skeleton and the second inner skeleton, and the axis line of the Z-direction receiving coil is the central axis of the first inner skeleton and the second inner skeleton; X The axis lines of the horizontal component receiving coil in the direction, the horizontal component receiving coil in the Y direction and the receiving coil in the Z direction are perpendicular to each other; the outer frame, the first inner frame, the central inner frame and the second inner frame are all insulating frames.

A borehole transient electromagnetic radial long-distance detection and observation system, comprising two three-component transceiver probe tubes according to claim 1 and a control probe tube arranged between the two three-component transceiver probe tubes; two three-component transceiver probe tubes; The transceiver probe tubes are probe tube A and probe tube B, and probe tube A and probe tube B have different probe tube parameters, and the control probe tube is probe tube C; probe tube A, probe tube C, and probe tube B are coaxially connected in turn. ; The probe parameters include the number of turns of the transmitting coil, the number of turns of the receiving coil, the length of the first inner frame and the second inner frame, and the length of the ferrite core.

The present invention also includes the following technical features:

Specifically, the probe A includes an outer skeleton A, a transmitting coil A is wound outside the outer skeleton A, and the axis of the transmitting coil A is the central axis of the outer skeleton A, and also includes a first inner skeleton arranged in the outer skeleton A in sequence. A. The central inner frame A and the second inner frame A, the axial direction of the first inner frame A and the second inner frame A and the extension direction of the long side of the central inner frame A are the same as the outer frame axial direction; in the center The ferrite core A is placed in the bobbin A, and the horizontal component receiving coil A in the X direction and the horizontal component receiving coil A in the Y direction are wound outside the central inner bobbin A. The ferrite core A is placed inside and the Z-direction receiving coil A is wound on the outside of the first inner skeleton A and the second inner skeleton A respectively, and the axis line of the Z-direction receiving coil A is the first inner skeleton A and the second inner skeleton A. The central axis of the inner frame A; the axis lines of the horizontal component receiving coil A in the X direction, the horizontal component receiving coil A in the Y direction and the receiving coil A in the Z direction are perpendicular to each other;

The probe tube B includes an outer skeleton B, a transmitting coil B is wound outside the outer skeleton B, and the axis line of the transmitting coil B is the central axis of the outer skeleton B, and also includes a first inner skeleton B, a center line arranged in the outer skeleton B in sequence. The inner frame B and the second inner frame B, the axial directions of the first inner frame B and the second inner frame B and the extension direction of the long side of the central inner frame B are the same as those of the outer frame; The ferrite core B is placed and the horizontal component receiving coil B in the X direction and the horizontal component receiving coil B in the Y direction are wound on the outside of the central inner skeleton B, and both are placed in the first inner skeleton B and the second inner skeleton B. The ferrite core B and the Z-direction receiving coil B are respectively wound outside the first inner bobbin B and the second inner bobbin B, and the axis lines of the Z-direction receiving coil B are the first inner bobbin B and the second inner bobbin B Central axis; the axis lines of the horizontal component receiving coil B in the X direction, the horizontal component receiving coil B in the Y direction, and the receiving coil B in the Z direction are perpendicular to each other.

Specifically, the number of turns of the transmitting coil A is less than the number of turns of the transmitting coil B; the number of turns of the receiving coil A in the Z direction is less than the number of turns of the receiving coil B in the Z direction; the lengths of the first inner skeleton A and the second inner skeleton A are Both are smaller than the lengths of the first inner skeleton B and the second inner skeleton B; the lengths of the ferrite cores A in the first inner skeleton A and the second inner skeleton A are both smaller than the first inner skeleton B and the second inner skeleton B The length of the inner ferrite core B.

Specifically, a transmitting circuit, an acquisition circuit and a storage device are arranged in the control probe;

The transmitting circuit is used to control the transmitting parameters of the transmitting coils of the probe A and the probe B. The frequency of the square wave current emitted by the probe A is higher than the frequency of the square wave current emitted by the probe B, and the emission current of the probe A is smaller than that of the probe B. emission current;

The acquisition circuit is used to receive and convert the receiving coil parameters of probe A and probe B, and the receiving time of probe A is shorter than that of probe B;

The storage device is used to store all the measurement parameters of the probe A and the probe B and the measured induced electromotive force;

The probe A detects the near area, and the probe B detects the far area.

Specifically, the transmitting circuit and the acquisition circuit are connected to each other through high-temperature wires, and the acquisition circuit writes the acquisition data into the storage device through the on-board SPI serial bus; the transmitting coil is connected to the transmitting circuit through an enameled copper wire, so The horizontal component receiving coils in the X direction, the horizontal component receiving coils in the Y direction, and the Z direction receiving coils are all connected to the acquisition circuit through enameled copper wires.

A method for long-distance detection and observation of borehole transient electromagnetic radial direction. The method adopts the observation system according to any one of claims 2 to 6 to perform detection and observation, and the observation points from the orifice to the bottom of the hole are the observation points in sequence. Position 0, observation point 1, observation point 2, ..., observation point n, where n is the observation point at the bottom of the hole; the method specifically includes the following steps:

Step 1: First, the probe A moves to the observation point 1. At this time, the probe B is located at the observation point 0. The probe A starts to transmit and receive at the observation point 1. After completion, the probe B is at the observation point 0. transmit and receive;

Step 2, then the probe A and the probe B continue to move forward along the borehole, and the probe A moves to the observation point 2. At this time, the probe B is located at the observation point 1, and the probe A starts at the observation point 2. Transmit and receive, after completion, probe B transmits and receives at observation point 1;

Step 3: Move the probe A and the probe B to the bottom of the hole in turn and repeat the above observation method at each observation point until the bottom of the hole;

In step 4, all the measured parameters of the probe A and the probe B and the measured induced electromotive force are stored in the storage device to complete the long-distance detection of the borehole transient electromagnetic radial direction.

Specifically, the measurement parameters include the wire diameter of the coil, the number of coil turns, the coil winding radius, the emission current intensity, the length of the ferrite core, the number of coil winding layers, the coil winding side length, and the core thickness.

A drilling transient electromagnetic radial long-distance detection observation data processing method, the method according to the measurement parameters of the probe tube A and the probe tube B according to claim 8, the measured induced electromotive force of the probe tube A and the probe tube B are all in accordance with: Normalize by the following formula:

In formulas (1) and (2),

V represents the induced electromotive force, V _{z is normalized to} the normalized induced electromotive force in the Z direction, V _z is the measured induced electromotive force in the Z direction, V _{x/y is normalized to} the normalized induced electromotive force in the X or Y direction, V _{x/ The measured} y is the measured induced electromotive force in the X or Y direction;

a represents the wire diameter of the wire, a _transmit is the wire diameter of the transmitting coil, a _{z receive} is the wire diameter of the receiving coil wire in the Z direction, and a _x/y _receive is the wire diameter of the receiving coil wire in the X or Y direction;

n represents the number of turns of the coil, n is the number of turns of the _transmitting coil, n _z is the number of turns of the receiving coil in the Z direction, and n _x/y is the number of turns of the receiving coil in the X or Y direction;

When the outer skeleton is cylindrical, the axis line of the transmitting coil is the central axis of the outer skeleton, and the corresponding r _emission is the winding radius of the transmitting coil; when the first inner skeleton and the second inner skeleton are cylindrical, The axis line of the receiving coil in the Z direction is the central axis of the first inner skeleton and the second inner skeleton, and the corresponding r _{z receiving} is the winding radius of the receiving coil in the Z direction;

I represents the emission current intensity;

L _z is the length of the ferrite core corresponding to the receiving coil in the Z direction;

c represents the number of winding layers of the horizontal component receiving coil in the X or Y direction;

l represents the winding side length of the horizontal component receiving coil in the X or Y direction, l _{x/y receiving length} is the length of the long side of the horizontal component receiving coil in the X or Y direction, l _{x/y receiving short} is the X or Y direction The length of the short side of the horizontal component receiving coil;

When the central inner skeleton is a cuboid, the corresponding H _x/y represents the core thickness of the ferrite core corresponding to the horizontal component in the X or Y direction;

The above-mentioned normalized data is calibrated and spliced at the observation point, and the long-term continuous and stable observation data of the observation point is obtained.

Specifically, performing observation point calibration and splicing on the normalized data includes: for the same observation point data, excluding the data of the late unstable section of probe A, excluding the data of the early saturated section of probe B, and then comparing the two sets of data Splicing is performed to obtain long-term continuous and stable observation data at the observation point.

Compared with the prior art, the present invention has the following beneficial technical effects:

The invention realizes the detection of geological information in the radial distance of the borehole, and the detection radius is more than twice that of the prior art. Drilling spacing, reducing the number of drilling holes and reducing construction costs.

Description of drawings

FIG. 1 is a schematic structural diagram of a three-component transceiver probe according to the present invention.

FIG. 2 is a schematic diagram of the drilling transient electromagnetic radial long-distance detection and observation system of the present invention.

FIG. 3 is a schematic diagram of the alternate detection and propulsion mode of probe tube A and probe tube B. FIG.

Figure 4 is a graph comparing the observed data curves of probe A and probe B.

Figure 5 is a graph of the data synthesis curve after normalization.

The meaning of the reference numerals: 1. The outer frame, 2. The transmitting coil, 3. The first inner frame, 4. The central inner frame, 5. The second inner frame, 6. The horizontal component receiving coil in the X direction, 7. The Y direction Horizontal component receiving coil, 8. Z direction receiving coil; 10. Probe A, 20. Probe C, 30. Probe B.

The present invention will be described in detail below with reference to the accompanying drawings and specific embodiments.

Detailed ways

The invention proposes a three-component transceiver probe tube and a borehole transient electromagnetic observation system and method using the combination of two sets of three-component transceiver probe tubes. Different probe tube parameters are respectively set, and a unique three-component coil arrangement is designed to ensure comprehensive Detect geoelectrical information near and far radially from the borehole. Among them, when the probe A probes near, the energy is small, the late signal is poor, and cannot reflect the distant information; the probe B probes far, the energy is large, the early signal is saturated, and the near information cannot be reflected (as shown in Figure 4). The far data is added to the back of the near data to form a global detection from far to near (see Figure 5).

Following the above technical solutions, specific embodiments of the present invention are given below. It should be noted that the present invention is not limited to the following specific embodiments, and all equivalent transformations made on the basis of the technical solutions of the present application all fall into the protection scope of the present invention. . The present invention will be described in further detail below in conjunction with the embodiments.

Example 1:

This embodiment provides a three-component transceiver probe, such as probe A or probe B in FIG. 1 and FIG. 2 , which includes an exoskeleton, a transmitting coil is wound outside the exoskeleton, and the axis of the transmitting coil is the center of the exoskeleton. The axis; also includes a first inner frame, a central inner frame and a second inner frame arranged in the outer frame in sequence; a ferrite core is placed in the central inner frame and a horizontal component in the X direction is wound outside the central inner frame to receive The coil and the horizontal component receiving coil in the Y direction, the ferrite core is placed in the first inner skeleton and the second inner skeleton, and the Z direction receiving coil is respectively wound outside the first inner skeleton and the second inner skeleton and the Z direction The axis line of the receiving coil is the center axis of the first inner skeleton and the second inner skeleton; the axis lines of the horizontal component receiving coil in the X direction, the horizontal component receiving coil in the Y direction and the receiving coil in the Z direction are perpendicular to each other; the outer skeleton , The first inner frame, the central inner frame and the second inner frame are all insulating frames.

Specifically, in this embodiment, the outer frame is cylindrical, the central inner frame is rectangular, the ferrite core in the central inner frame is also rectangular, and the first inner frame and the second inner frame are cylinders The ferrite cores in the first inner skeleton and the second inner skeleton are cylindrical; in other embodiments, the inner skeleton can be set as a cuboid or a The ferrite core is also set in a cuboid or cylindrical shape according to the inner skeleton structure; both can achieve its detection function.

Example 2:

This embodiment provides a borehole transient electromagnetic radial long-distance detection and observation system, as shown in FIG. 2 , including two above-mentioned three-component transceiver probes and a control probe disposed between the two three-component transceiver probes ; The two three-component transceiver probe tubes are probe tube A and probe tube B, and probe tube A and probe tube B have different probe tube parameters, and the control probe tube is probe tube C; probe tube A, probe tube C and probe tube B are connected coaxially in sequence; the parameters of the probe tube include the number of turns of the transmitting coil, the number of turns of the receiving coil, the length of the first inner frame and the second inner frame, and the length of the cylindrical ferrite core. The parameters of the probe also include: outer diameter of the outer skeleton, wire diameter of the transmitting coil, number of turns of the transmitting coil, size of the central inner skeleton, size of the cuboid ferrite core, the horizontal component of the X and Y directions, the number of winding layers of the receiving coil, X , The wire diameter of the horizontal component receiving coil in the Y direction, the number of turns of the horizontal component receiving coil in the X and Y directions, the size of the first inner skeleton and the second inner skeleton, the size of the cylindrical ferrite core, the wire diameter of the receiving coil in the Z direction, and The number of turns of the receiving coil in the Z direction.

The probe tube A includes a cylindrical outer skeleton A, a transmitting coil A is wound outside the outer skeleton A, and the axis line of the transmitting coil A is the central axis of the outer skeleton A, and also includes a cylindrical first arranged in the outer skeleton A in sequence. An inner frame A, a rectangular central inner frame A and a cylindrical second inner frame A, the axial directions of the first inner frame A and the second inner frame A and the extension direction of the long side of the central inner frame A are the same as the outer frame A. The axial direction of the skeleton is the same; a rectangular parallelepiped ferrite core A is placed in the central inner skeleton A, and the horizontal component receiving coil A in the X direction and the horizontal component receiving coil A in the Y direction are wound outside the central inner skeleton A. A cylindrical ferrite core A is placed in both an inner skeleton A and a second inner skeleton A, and a Z-direction receiving coil A and a Z-direction receiving coil A are wound outside the first inner skeleton A and the second inner skeleton A, respectively. The axis line is the central axis of the first inner frame A and the second inner frame A; the axis lines of the horizontal component receiving coil A in the X direction, the horizontal component receiving coil A in the Y direction and the receiving coil A in the Z direction are perpendicular to each other.

The probe tube B includes a cylindrical outer skeleton B, a transmitting coil B is wound outside the outer skeleton B, and the axis line of the transmitting coil B is the central axis of the outer skeleton B, and also includes a cylindrical first arranged in the outer skeleton B in sequence. An inner frame B, a rectangular central inner frame B and a cylindrical second inner frame B, the axial directions of the first inner frame B and the second inner frame B and the extension direction of the long side of the central inner frame B are the same as the outer frame B. The axial direction of the skeleton is the same; a rectangular parallelepiped ferrite core B is placed in the central inner skeleton B and a horizontal component receiving coil B in the X direction and a horizontal component receiving coil B in the Y direction are wound outside the central inner skeleton B. A cylindrical ferrite core B is placed in both an inner bobbin B and a second inner bobbin B, and a Z-direction receiving coil B is wound on the outside of the first inner bobbin B and the second inner bobbin B respectively. The axis line is the central axis of the first inner frame B and the second inner frame B; the axis lines of the horizontal component receiving coil B in the X direction, the horizontal component receiving coil B in the Y direction and the receiving coil B in the Z direction are perpendicular to each other.

The number of turns of the transmitting coil A is less than the number of turns of the transmitting coil B; the number of turns of the receiving coil A in the Z direction is less than the number of turns of the receiving coil B in the Z direction; the lengths of the first inner skeleton A and the second inner skeleton A are smaller than the first inner skeleton A The length of the bobbin B and the second inner bobbin B; the length of the cylindrical ferrite core A is smaller than the length of the cylindrical ferrite core B.

More specifically, in this embodiment, the probe tube A includes a cylindrical outer skeleton A, the outer diameter of the outer skeleton A is 50 mm (not limited), and the outside is wound with an enameled wire with a wire diameter of 1 mm (not limited to) to form the transmitting coil A. , the transmitting coil A is wound with 25 turns (not limited to), and the normal direction of the center of the transmitting coil A is the extending direction of the probe tube A. A cylindrical first inner frame A, a rectangular parallelepiped central inner frame A and a cylindrical second inner frame A are arranged in the outer frame A along the axial direction; the size of the rectangular parallelepiped central inner frame A is 22mm×22mm× 602mm (not limited), a rectangular cylindrical ferrite core is placed inside the center inner skeleton A and its size is 20mm × 20mm × 600mm (not limited), on the outside of the center inner skeleton A along the long side of the center inner skeleton A. The enameled wire is respectively wound for the horizontal component receiving coil A in the X and Y directions, which can be wound in 2 layers (not limited), and 640 turns (not limited) of enameled wire with a wire diameter of 0.1 mm (not limited) are used. The length of the first inner frame A and the second inner frame A are both 162mm (not limited) and the diameters are both 34mm (not limited), and cylindrical ferrites are placed inside the first inner frame A and the second inner frame A respectively. Body magnetic core, the length of the magnetic core is 160mm (not limited), the diameter is 32mm (not limited), and the outer sides of the first inner skeleton A and the second inner skeleton A are respectively wound with enameled wires with a wire diameter of 0.6 mm (not limited) in the Z direction The receiving coil A, the normal direction of the center of the receiving coil A is the extending direction of the probe A, and the number of turns of the two receiving coils A is 125 turns (not limited).

In this embodiment, the probe tube B includes a cylindrical outer skeleton B with an outer diameter of 50mm (not limited to), and the outside is wound with an enameled wire with a wire diameter of 1mm (not limited to) for 50 turns (not limited to). Limited to), the normal direction of the center of the transmitting coil B is the extending direction of the probe tube B. A cylindrical first inner frame B, a rectangular parallelepiped central inner frame B and a cylindrical second inner frame B are sequentially arranged in the outer frame B along the axial direction. The size of the central inner frame B is 22mm×22mm×602mm (not limited to), place a rectangular cylindrical ferrite core inside the central inner skeleton B, with a size of 20mm × 20 mm × 600 mm (not limited), and wind X and Y with enameled wires on the outside of the central inner skeleton B along the long side of the skeleton. The horizontal component receiving coil of the direction can be wound in 4 layers (not limited), and 640 turns (not limited) are wound with enameled wire with a wire diameter of 0.1mm (not limited). The length of the first inner frame B and the second inner frame B are both 322mm (not limited) and the diameters are both 34mm (not limited), and cylindrical ferrites are placed inside the first inner frame B and the second inner frame B respectively. Magnetic core, the length of the magnetic core is 320mm (not limited), the diameter is 32mm (not limited), and the outer sides of the first inner skeleton B and the second inner skeleton B are respectively wound with enameled wires with a wire diameter of 0.6 mm (not limited) to receive in the Z direction Coil B, the normal direction of the center of the receiving coil B is the extending direction of the probe tube B, and the turns of the two receiving coils B are both 500 turns (not limited).

The probe tube A and the probe tube B are connected by the control probe tube C. The length of the probe tube C is 1 section of drill pipe length (not limited), so that the control probe tube A and probe tube B can be located at the same observation point twice before and after. bit.

A battery, a control circuit, a transmitting circuit, an acquisition circuit and a storage device are arranged in the control probe. The battery is used to supply power to the entire observation system; the control circuit is used to control the working sequence of probe A and probe B; the transmitting circuit is used to control the transmitting parameters of the transmitting coils of probe A and probe B, and the square wave emitted by probe A The current frequency is higher than that of the square wave current emitted by probe B, and the emission current of probe A is smaller than that of probe B; the acquisition circuit is used to receive and convert the receiving coils of probe A and probe B to receive parameters, and probe A receives The time is shorter than the receiving time of probe B; the storage device is used to store all measurement parameters of probe A and probe B and the measured induced electromotive force; in this embodiment, probe A detects the near area, and probe B detects the far area. Probe A has a radial detection distance of 0-30 m in the near region, and probe B has a radial detection distance of 30-60 m in the far region. In other embodiments, the radial detection distance is different according to different geological parameters. The control circuit, the transmitting circuit and the acquisition circuit are connected to each other through high-temperature wires, and the acquisition circuit writes the acquired data into the storage device through the on-board SPI serial bus; the transmitting coil is connected to the transmitting circuit through an enameled copper wire, and the horizontal component in the X direction The receiving coil, the horizontal component receiving coil in the Y direction and the receiving coil in the Z direction are all connected to the acquisition circuit through enameled copper wires.

In this embodiment, the battery in the probe C is isolated and output two channels of intrinsically safe power supplies after being processed by the step-down and current-limiting protection circuits, to supply power to the transmitting circuit and the acquisition circuit respectively.

The transmitting circuit receives the bipolar pulse square wave signal provided by the control circuit and outputs it through the full-bridge circuit after being isolated and driven, so as to realize the excitation and construction of the transient electromagnetic primary field.

The acquisition circuit includes a MCU control unit, a three-channel 24-bit (not limited to) AD analog-to-digital conversion unit, a signal conditioning filter unit and a control timing output unit. Its function is to receive the secondary field signal generated by the induced eddy current through the three-component coil. The secondary field signals are respectively sent to the AD analog-to-digital conversion circuit of the corresponding channel after signal conditioning such as amplification and filtering, and the converted data is stored in the storage device after real-time superposition operation processing.

The storage device uses a 64GB (not limited) high-speed SD data card as the storage medium for the observation system to collect and process data, and complete data communication with the MCU control unit through a high-speed serial port. When the data needs to be read, the storage device can be accessed through the USB2.0 interface. , transfer the data to the local computer and save it as a data file.

The battery is responsible for supplying power to the entire observation system. The observation system battery is composed of a single cell through a series-parallel combination to form a battery pack as its power supply. The transmitter circuit and the control acquisition circuit are powered by independent battery packs. The transmitter circuit power supply battery capacity is 10Ah ( Not limited), the average equivalent emission current of the two emission parameter devices is 1.5A (not limited), and the equivalent emission current calculated according to the duty cycle of 50% (not limited) is 0.75A (not limited), so the working time is calculated as ( 10Ah/0.75A)*0.9=12h, the working current of the receiving control acquisition circuit is 400mA (not limited), and the battery capacity is 5Ah (not limited), so the working time is (5Ah/0.4A)*0.9=11.25h, the overall operation of the observation system The time is not less than 10 hours.

There is a tapered head at the front end of the probe pipe A, which is convenient for the drilling rig to push, and ensures that the front is not blocked by stones or mud protruding from the hole wall.

Example 3:

This embodiment provides a method for long-distance detection and observation of borehole transient electromagnetic radial direction. The method adopts the above observation system to perform detection and observation. The observation points from the orifice to the bottom of the hole are observation point 0 and observation point 1 in order , observation point 2, ..., observation point n, n is the observation point at the bottom of the hole; the method specifically includes the following steps:

In step 4, all the measured parameters of the probe A and the probe B and the measured induced electromotive force are stored in the storage device to complete the long-distance detection of the borehole transient electromagnetic radial direction. The measurement parameters include the wire diameter of the coil, the number of coil turns, the coil winding radius, the emission current intensity, the length of the magnetic core, the number of coil winding layers, the length of the coil winding side, and the thickness of the magnetic core.

In this embodiment, the control circuit controls the working sequence of probe A and probe B, and the control circuit controls probe A to work first, and probe B to work later. As shown in Figure 3, firstly, the probe A moves to the observation point 1. At this time, the probe B is at the observation point 0. The probe A starts to transmit and receive at the observation point 1. After completion, the probe B is at the observation point. Bit 0 transmits and receives; then probe A and probe B continue to move forward along the borehole, probe A moves to observation point 2, and probe B is at observation point 1, and probe A begins to observe Point 2 transmits and receives. After completion, probe B transmits and receives at observation point 1. Move probe A and probe B and repeat the observation method until the bottom of the hole.

The transmitting circuit controls the transmitting parameters of the transmitting coils of probe A and probe B. Probe A mainly detects the radial near area of the borehole, and the emitted square wave current frequency is high, which can be set to 25Hz-6.25Hz (not limited), and the emission current intensity is small, which can be set to 0.8A (not limited); Pipe B mainly detects the radially far area of the borehole, and the frequency of the emitted square wave current is low, which can be set to 2.5Hz-0.625Hz (not limited), and the emission current intensity is relatively large, which can be set to 2A (not limited).

The acquisition circuit controls the receiving coils of probe A and probe B to receive parameters. Probe A mainly detects the radially near area of the borehole, and the transmitting frequency in the receiving time domain is correspondingly short, and when the transmitting frequency is 25Hz, it is 10ms; Probe B mainly detects the radially far area of the borehole, and the transmitting frequency in the receiving time domain is Correspondingly, it is longer, and when the transmission frequency is 0.625Hz, it is 400ms; the number of times of superposition can be set between 50 and 500 times (not limited).

The storage device stores all measurement-related parameters of probe A and probe B and the measured induced electromotive force values. It mainly includes the diameter of the transmitting coil, the number of turns, the radius of the coil, the intensity of the transmitting current, the diameter of the receiving coil, the number of turns, the radius of the coil, the length of the coil side, the number of coil layers, the length of the magnetic core, the number of superpositions, the sampling frequency, etc., as well as the measuring points Number, line number, transmission frequency, sampling time, induced electromotive force and other information.

As shown in Figure 4, it is a comparison chart of the observed data curves of probe A and probe B, in which the abscissa is the sampling time, and the ordinate is the induced electromotive force. According to the curve, the resistivity in the radial direction of the borehole can be calculated. The early signal of curve A Stable and reliable, the late signal has interference, only the shallow resistivity can be calculated, that is, the probe A detects the near area, the early signal of the B curve is saturated and distorted, and the late signal is stable and reliable, and only the deep resistivity can be calculated, that is, the probe B Detect remote areas.

Example 4:

A method for processing drilling transient electromagnetic radial long-distance detection observation data. After the acquisition is completed, the measured data of probe A and probe B are imported into a computer, and probe A is measured according to the measurement parameters of probe A and probe B. and the measured induced electromotive force of probe B are normalized according to the following formula:

In formulas (1) and (2),

r _transmitting is the winding radius of the transmitting coil, r _{z receiving} is the winding radius of the receiving coil in the Z direction;

I represents the emission current intensity;

L _z is the length of the cylindrical ferrite core corresponding to the receiving coil in the Z direction;

H _x/y represents the core thickness of the rectangular parallelepiped ferrite corresponding to the horizontal component in the X or Y direction;

The above-mentioned normalized data is calibrated and spliced at the observation point, and the long-term continuous and stable observation data of the observation point is obtained. The calibration and splicing of observation points for the normalized data includes: for the same observation point data, excluding the data of the late unstable section of probe A, and excluding the data of the early saturated section of probe B, and then splicing the two sets of data, Obtain long-term continuous and stable observation data at the observation point.

In this embodiment, the measurement point calibration is performed on the data of the probe A and the normalized data of the probe B respectively. For the same point data, the data of the unstable segment in the late stage of the probe A, such as 20ms (not limited to), are excluded. Eliminate the early saturated section of probe B, such as the data before 20ms (not limited to), and then splicing the two sets of data to obtain long-term continuous and stable observation data of the measurement point, forming a global detection from far to near, as shown in Figure 5 .

In the present invention, the probe tube A can detect the radial detection distance of 0-30m, and the probe tube B can detect the radial detection distance of 30-60m.

Claims

A three-component transceiver probe is characterized in that it comprises an exoskeleton, a transmitting coil is wound outside the exoskeleton, and the axis of the transmitting coil is the center axis of the exoskeleton; it also comprises a first inner framework, a center line arranged in the exoskeleton in sequence The inner frame and the second inner frame; a ferrite core is placed in the central inner frame and a horizontal component receiving coil in the X direction and a horizontal component receiving coil in the Y direction are wound on the outside of the central inner frame. Ferrite cores are placed in the second inner skeleton, and Z-direction receiving coils are respectively wound outside the first inner skeleton and the second inner skeleton, and the axis lines of the Z-direction receiving coils are the first inner skeleton and the second inner skeleton The central axis; the axis lines of the horizontal component receiving coil in the X direction, the horizontal component receiving coil in the Y direction and the receiving coil in the Z direction are perpendicular to each other; the outer frame, the first inner frame, the central inner frame and the second inner frame are all Insulated skeleton.
A borehole transient electromagnetic radial long-distance detection and observation system, characterized in that it comprises two three-component transceiver probes according to claim 1 and a control probe disposed between the two three-component transceiver probes; The two three-component transceiver probe tubes are probe tube A and probe tube B, and probe tube A and probe tube B have different probe tube parameters, and the control probe tube is probe tube C; probe tube A, probe tube C, and probe tube B Coaxially connected in sequence; the probe parameters include the number of turns of the transmitting coil, the number of turns of the receiving coil, the lengths of the first inner frame and the second inner frame, and the length of the ferrite core.
The borehole transient electromagnetic radial long-distance detection and observation system according to claim 2, wherein the probe A comprises an outer skeleton A, and a transmitting coil A is wound outside the outer skeleton A and the axis of the transmitting coil A is The line is the central axis of the outer frame A, and also includes a first inner frame A, a central inner frame A and a second inner frame A that are sequentially arranged in the outer frame A. The axial direction of the first inner frame A and the second inner frame A is And the extension direction of the long side of the central inner skeleton A is the same as that of the outer skeleton; the ferrite core A is placed in the central inner skeleton A, and the horizontal component receiving coil A and X-direction are wound outside the central inner skeleton A. The horizontal component receiving coil A in the Y direction, the ferrite core A is placed in the first inner bobbin A and the second inner bobbin A, and the Z direction receiving coil is wound outside the first inner bobbin A and the second inner bobbin A respectively Coil A and the axis line of the receiving coil A in the Z direction are the central axes of the first inner frame A and the second inner frame A; the horizontal component receiving coil A in the X direction, the horizontal component receiving coil A in the Y direction, and the receiving coil A in the Z direction The axes are perpendicular to each other;

The probe tube B includes an outer skeleton B, a transmitting coil B is wound outside the outer skeleton B, and the axis line of the transmitting coil B is the central axis of the outer skeleton B, and also includes a first inner skeleton B, a center line arranged in the outer skeleton B in sequence. The inner frame B and the second inner frame B, the axial directions of the first inner frame B and the second inner frame B and the extension direction of the long side of the central inner frame B are the same as those of the outer frame; The ferrite core B is placed and the horizontal component receiving coil B in the X direction and the horizontal component receiving coil B in the Y direction are wound on the outside of the central inner skeleton B, and both are placed in the first inner skeleton B and the second inner skeleton B. The ferrite core B and the Z-direction receiving coil B are respectively wound outside the first inner bobbin B and the second inner bobbin B, and the axis lines of the Z-direction receiving coil B are the first inner bobbin B and the second inner bobbin B Central axis; the axis lines of the horizontal component receiving coil B in the X direction, the horizontal component receiving coil B in the Y direction, and the receiving coil B in the Z direction are perpendicular to each other.
The borehole transient electromagnetic radial long-distance detection and observation system according to claim 3, wherein the number of turns of the transmitting coil A is less than the number of turns of the transmitting coil B; the number of turns of the receiving coil A in the Z direction is less than that of the Z direction The number of turns of the direction receiving coil B; the lengths of the first inner skeleton A and the second inner skeleton A are both smaller than the lengths of the first inner skeleton B and the second inner skeleton B; The lengths of the ferrite cores A are all smaller than the lengths of the ferrite cores B in the first inner bobbin B and the second inner bobbin B.
The borehole transient electromagnetic radial long-distance detection and observation system according to claim 2, wherein a transmitting circuit, an acquisition circuit and a storage device are arranged in the control probe;

The transmitting circuit is used to control the transmitting parameters of the transmitting coils of the probe A and the probe B. The frequency of the square wave current emitted by the probe A is higher than the frequency of the square wave current emitted by the probe B, and the emission current of the probe A is smaller than that of the probe B. emission current;

The acquisition circuit is used to receive and convert the receiving coil parameters of probe A and probe B, and the receiving time of probe A is shorter than that of probe B;

The storage device is used to store all measurement parameters of probe A and probe B and the measured induced electromotive force;

The probe A detects the near area, and the probe B detects the far area.
The drilling transient electromagnetic radial long-distance detection and observation system according to claim 5, characterized in that, the transmitting circuit and the acquisition circuit are connected to each other through high-temperature wires, and the acquisition circuit connects the acquisition circuit through the SPI serial bus on the board. Data is written into the storage device; the transmitting coil is connected to the transmitting circuit through an enameled copper wire, and the horizontal component receiving coil in the X direction, the horizontal component receiving coil in the Y direction and the Z direction receiving coil are connected to the collecting coil through the enameled copper wire. circuit connection.
A method for long-distance detection and observation of borehole transient electromagnetic radial direction, characterized in that, the method adopts the observation system according to any one of claims 2 to 6 for detection and observation, and the observation points from the orifice to the bottom of the hole are used for detection and observation. The sequence is observation point 0, observation point 1, observation point 2, ..., observation point n, where n is the observation point at the bottom of the hole; the method specifically includes the following steps:

Step 1: First, the probe A moves to the observation point 1. At this time, the probe B is located at the observation point 0. The probe A starts to transmit and receive at the observation point 1. After completion, the probe B is at the observation point 0. transmit and receive;

Step 2, then the probe A and the probe B continue to move forward along the borehole, and the probe A moves to the observation point 2. At this time, the probe B is located at the observation point 1, and the probe A starts at the observation point 2. Transmit and receive, after completion, probe B transmits and receives at observation point 1;

Step 3: Move the probe A and the probe B to the bottom of the hole in turn and repeat the above observation method at each observation point until the bottom of the hole;

In step 4, all the measured parameters of the probe A and the probe B and the measured induced electromotive force are stored in the storage device to complete the long-distance detection of the borehole transient electromagnetic radial direction.
The method for long-distance detection and observation of borehole transient electromagnetic radial direction according to claim 7, wherein the measurement parameters include the wire diameter of the coil, the number of coil turns, the coil winding radius, the emission current intensity, the ferrite Core length, number of coil winding layers, coil winding side length, core thickness.
A method for processing drilling transient electromagnetic radial long-distance detection observation data, characterized in that the method is based on the actual measurement of the probe A and the probe B according to the measurement parameters of the probe A and the probe B as claimed in claim 8 The induced electromotive force is normalized according to the following formula:

In formulas (1) and (2),

V represents the induced electromotive force, V z is normalized to the normalized induced electromotive force in the Z direction, V z is the measured induced electromotive force in the Z direction, V x/y is normalized to the normalized induced electromotive force in the X or Y direction, V x/ The measured y is the measured induced electromotive force in the X or Y direction;

a represents the wire diameter of the wire, a transmit is the wire diameter of the transmitting coil, a z receive is the wire diameter of the receiving coil wire in the Z direction, and a x/y receive is the wire diameter of the receiving coil wire in the X or Y direction;

n represents the number of turns of the coil, n is the number of turns of the transmitting coil, n z is the number of turns of the receiving coil in the Z direction, and n x/y is the number of turns of the receiving coil in the X or Y direction;

When the outer skeleton is cylindrical, the axis line of the transmitting coil is the central axis of the outer skeleton, and the corresponding r emission is the winding radius of the transmitting coil; when the first inner skeleton and the second inner skeleton are cylindrical, The axis line of the receiving coil in the Z direction is the central axis of the first inner frame and the second inner frame, and the corresponding r z receiving is the winding radius of the receiving coil in the Z direction;

I represents the emission current intensity;

L z is the length of the ferrite core corresponding to the receiving coil in the Z direction;

c represents the number of winding layers of the horizontal component receiving coil in the X or Y direction;

l represents the winding side length of the horizontal component receiving coil in the X or Y direction, l x/y receiving length is the length of the long side of the horizontal component receiving coil in the X or Y direction, l x/y receiving short is the X or Y direction The length of the short side of the horizontal component receiving coil;

When the central inner skeleton is a cuboid, the corresponding H x/y represents the core thickness of the ferrite core corresponding to the horizontal component in the X or Y direction;

The above-mentioned normalized data is calibrated and spliced at the observation point, and the long-term continuous and stable observation data of the observation point is obtained.
The method for processing the observation data of borehole transient electromagnetic radial long-distance detection according to claim 9, characterized in that, performing observation point calibration and splicing on the normalized data comprises: for the same observation point data, removing The data of the unstable section in the late stage of the probe A, and the data of the early saturated section of the probe B are excluded, and then the two sets of data are spliced to obtain the long-term continuous and stable observation data of the observation point.