A multi-directional shallow electrical prospecting device

Abstract

The application relates to the technical field of electrical prospecting, in particular to a multidirectional shallow electrical prospecting device, which comprises a first bearing panel and a second bearing panel; a transmitter and at least two groups of transmitting electrode groups are arranged on the first bearing panel; a receiver and at least two groups of receiving electrode groups are arranged on the second bearing panel; the transmitter is connected with the transmitting electrode groups and is used for injecting electric current into the ground; the receiver is connected with the receiving electrode groups and is used for collecting voltage signals; the transmitter and the receiver are respectively integrated with a positioning device and an azimuth detection device; the coordinates of the corresponding transmitting electrode groups / receiving electrode groups are determined through the positioning device and the azimuth detection device; the transmitter is configured to switch the groups of transmitting electrode groups in a predetermined sequence to output electric current; and the receiver is configured to continuously collect the voltage signals of the groups of receiving electrode groups. The device has the effects of reducing manpower and material resources, suppressing the influence of abnormal bodies and improving the stability of induced polarization parameters.

Description

Technical Field

[0001] This application relates to the technical field, and in particular to a multi-directional shallow electrical resistivity tomography apparatus. Background Technology

[0002] Geophysical exploration techniques are crucial for understanding subsurface geological structures and have wide applications in numerous fields such as resource exploration and engineering geological surveys. Resistivity methods, as one of the important tools in geophysical exploration, can utilize the differences in conductivity among different subsurface rocks. By observing and studying the distribution patterns of artificially established stable subsurface current fields, they can infer stratigraphic structure, locate subsurface targets, and solve related geological problems. (See attached image) Figure 1 As shown, current is injected through electrodes A and B to establish a current field underground (as shown by the red line) and form a voltage equipotential surface (as shown by the blue line). The voltage between M and N is measured, and the current between A and B is recorded. Based on the positional relationship of the four electrodes A, B, M, and N, the apparent resistivity is calculated, corresponding to the conductivity of a certain area underground. By changing the distance and relative position of A, B, M, and N, the electrical characteristics of the entire underground space can be obtained. The time-domain induced polarization method, based on the induced polarization effect of rocks and ores, also plays an important role in finding metal deposits, groundwater, and solving engineering geological problems. Its working device is the same as that of the resistivity method. The current waveform is generally a square wave with a 50% duty cycle. After powering and de-energizing the uneven ground, the current does not rapidly increase or decrease to 0, but rather exhibits a slow rise or fall. The voltage during the power-off process is the secondary voltage. Calculating the ratio of the secondary voltage to the voltage when the current is supplied steadily yields the apparent polarizability, reflecting the strength of the induced polarization effect. By combining apparent resistivity and apparent polarizability for post-processing and interpretation, the electrical characteristics of underground space can be comprehensively and holistically reflected.

[0003] In practical applications of resistivity methods and time-domain excited polarization methods, traditional high-density electrical resistivity methods (EDS) are commonly used. High-density EDS operates using an array-type device, typically consisting of a main unit, electrode switches, and cables. Centralized high-density EDS instruments connect to the main unit via wires equal to the number of electrodes, using electrode switching switches (composed of relays) to switch between different electrodes and electrode spacings. Distributed high-density EDS instruments distribute electrode switching switches across the cables and electrodes; different cables can be connected to increase the number of electrodes, thus reducing the core count and weight of individual cables to some extent.

[0004] However, existing high-density electrical resistivity tomography (ERT) methods have several drawbacks. They can only transmit current and measure voltage along the survey line, leading to significant errors in data processing and two-dimensional inversion when dealing with subsurface three-dimensional electrical anomalies or highly anisotropic conditions (common in shallow electrical resistivity exploration). Furthermore, the cables used in high-density ERT are bulky, making deployment cumbersome and requiring substantial manpower and resources. Electrode spacing is also constrained by the cables, limiting flexibility. Additionally, the thin conductors, low supply current, and difficulty in deploying non-polarized electrodes make it challenging to measure high-precision induced polarization parameters. Summary of the Invention

[0005] This application provides a multi-directional shallow electrical exploration device, which achieves the effects of reducing manpower and material resources, suppressing the influence of anomalies, and improving the stability of induced polarization parameters.

[0006] The above-mentioned objective of this application is achieved through the following technical solution:

[0007] This application provides a multi-directional shallow electrical resistivity tomography (EPT) device, comprising: a first support panel and a second support panel; the first support panel is provided with a transmitter and at least two sets of transmitting electrode groups, and the second support panel is provided with a receiver and at least two sets of receiving electrode groups; the transmitter is connected to the transmitting electrode groups for injecting current into the ground, and the receiver is connected to the receiving electrode groups for acquiring voltage signals; the transmitter and the receiver are respectively integrated with a positioning device and an azimuth angle detection device, the coordinates of the corresponding transmitting electrode groups / receiving electrode groups are determined by the positioning device and the azimuth angle detection device, the transmitter is configured to sequentially switch each set of transmitting electrode groups to output current according to a predetermined time sequence, and the receiver is configured to continuously acquire the voltage signals of each set of receiving electrode groups.

[0008] By adopting the above technical solution, during the measurement process, two operators simultaneously move along the survey line, one carrying the first carrier panel and the other carrying the second carrier panel. They measure according to the preset transmission and reception positions. Upon arrival, the transmitting and receiving electrode groups are coupled to the ground, and data acquisition begins. This eliminates the need for cumbersome cable laying, effectively reducing the manpower, material resources, and workload required for deploying shallow electrical exploration equipment. During the acquisition process, the transmitter first uses one set of transmitting electrode groups to emit current. After a period of time, it switches to another set of transmitting electrode groups to emit current. During this process, the receiver continuously acquires the voltage signals from all receiving electrode groups. This allows each measuring point to measure multiple sets of data from different transmission and reception orientations, ensuring that subsequent data processing and inversion avoid the influence of shallow three-dimensional electrical anomalies and anisotropy. Furthermore, since the transmitter and the transmitting electrode assembly are integrated together on the first carrier panel, it is convenient to use thick cables to connect the transmitter and the transmitting electrode assembly, ensuring that the transmitter can transmit at a higher power. In this way, the first carrier panel and the second carrier panel can still measure a stable secondary voltage when they are far apart, and stable induced polarization parameters such as apparent polarization can be obtained.

[0009] Preferably, the first support panel and the second support panel are both disc-shaped structures.

[0010] By adopting the above technical solution, the disc-shaped structure is easy to carry manually and facilitates the uniform placement of multiple sets of transmitting / receiving electrodes.

[0011] Preferably, the transmitter is located at the center of the first carrier panel, and the receiver is located at the center of the second carrier panel.

[0012] By adopting the above technical solution, this layout makes the center of gravity of the device more stable, and it is easy to carry and operate.

[0013] Preferably, the transmitting electrode group and the receiving electrode group are arranged in a ring array along the edges of the corresponding first carrier panel and second carrier panel.

[0014] By adopting the above technical solution, this distribution method enables the transmitting electrode group and the receiving electrode group to be evenly distributed in the circumferential direction, which can inject current into the ground from multiple directions and collect voltage signals, further improving the comprehensiveness of exploration.

[0015] Preferably, the transmitting electrode group comprises four groups and is distributed in four symmetrical positions on the first carrier panel, and the receiving electrode group comprises four groups and is distributed in four symmetrical positions on the second carrier panel.

[0016] By adopting the above technical solutions, such a distribution can form a more regular current field and voltage acquisition pattern, which facilitates data processing and analysis.

[0017] Preferably, the conductive paths between the transmitting electrode group and the transmitter, and between the receiving electrode group and the receiver, use wires with a cross-sectional area ≥ 1.5 mm².

[0018] By adopting the above technical solution, it is ensured that the transmitter can transmit at a higher power. In this way, the first and second carrier panels can still measure a stable secondary voltage when they are far apart, and stable induced polarization parameters such as apparent polarization can be obtained.

[0019] Preferably, the positioning device is a real-time dynamic differential positioning module, used to locate the coordinates of the transmitter and the receiver; the azimuth angle detection device is a three-component magnetoresistive sensor, used to determine the azimuth angle of the transmitting electrode group and the receiving electrode group.

[0020] By adopting the above technical solution, the positioning device can obtain the midpoint coordinates of the transmitter and receiver in real time, and the azimuth angle detection device can determine the azimuth angle of the transmitting electrode group and the receiving electrode group. This information is very important for accurately calculating the apparent resistivity and apparent polarizability, because the apparent resistivity and apparent polarizability are closely related to the position and orientation of the electrodes.

[0021] Preferably, the transmitter and the receiver are each equipped with a wireless communication module, and the coordinate signal collected by the positioning device and the azimuth angle signal collected by the azimuth angle detection device are transmitted to an external data processing device in real time through the wireless communication module.

[0022] Preferably, the external data processing device calculates the apparent resistivity and apparent polarizability of the formation based on the coordinate signal and the azimuth signal, combined with the current parameters of the transmitter and the voltage parameters of the receiver.

[0023] In summary, this application includes at least the following beneficial technical effects:

[0024] 1. Since the transmitter and transmitting electrode assembly are integrated on the first bearing panel and the receiver and receiving electrode assembly are integrated on the second bearing panel, there is no need to lay cumbersome cables, which effectively reduces the manpower, material resources and workload of laying shallow electrical exploration equipment.

[0025] 2. During the acquisition process, the transmitter first uses one set of transmitting electrodes to transmit current for a period of time, then switches to another set of transmitting electrodes to transmit current. During this process, the receiver continuously acquires the voltage signals of all receiving electrode sets. In this way, each measuring point can measure multiple sets of data from different transmitting and receiving azimuths, ensuring that subsequent data processing and inversion avoid the influence of shallow three-dimensional electrical anomalies and anisotropy.

[0026] 3. Since the transmitter and the transmitting electrode assembly are integrated together on the first carrier panel, it is convenient to use thick cables to connect the transmitter and the transmitting electrode assembly, ensuring that the transmitter can transmit at a higher power. In this way, the first carrier panel and the second carrier panel can still measure a stable secondary voltage when they are far apart, and stable induced polarization parameters such as apparent polarization can be obtained. Attached Figure Description

[0027] Figure 1 This is a schematic diagram of an existing resistivity method apparatus;

[0028] Figure 2 This is a top view of the exploration apparatus according to an embodiment of this application;

[0029] Figure 3 This is a front view of the exploration apparatus according to an embodiment of this application;

[0030] Figure 4 This is a left view of the exploration apparatus according to an embodiment of this application. Detailed Implementation

[0031] The following embodiments will help those skilled in the art to further understand the function of this application, but do not limit this application in any way. It should be noted that those skilled in the art can make several modifications and improvements without departing from the concept of this application. These all fall within the protection scope of this application.

[0032] In the following description, specific details such as particular system architectures and techniques are set forth for illustrative purposes and not for limitation, in order to provide a thorough understanding of the embodiments of this application. However, those skilled in the art will understand that this application may also be implemented in other embodiments without these specific details. In other instances, detailed descriptions of well-known systems, circuits, and methods are omitted so as not to obscure the description of this application with unnecessary detail.

[0033] It should be understood that, when used in this application specification and the appended claims, the term "comprising" indicates the presence of the described features, integrals, steps, operations, elements and / or components, but does not exclude the presence or addition of one or more other features, integrals, steps, operations, elements, components and / or a collection thereof.

[0034] Example 1

[0035] Reference Figures 2 to 4This embodiment provides a multi-directional shallow electrical resistivity tomography (EPT) device, including: a first support panel ④ and a second support panel; the first support panel ④ is provided with a transmitter ③ and at least two sets of transmitting electrode groups ①, and the second support panel is provided with a receiver and at least two sets of receiving electrode groups; the transmitter ③ is connected to the transmitting electrode groups ① for injecting current into the ground, and the receiver is connected to the receiving electrode groups for collecting voltage signals; the transmitter ③ and the receiver are respectively integrated with a positioning device and an azimuth angle detection device, and the coordinates of the corresponding transmitting electrode group ① / receiving electrode group are determined by the positioning device and the azimuth angle detection device; the transmitter ③ is configured to sequentially switch each set of transmitting electrode groups ① to output current according to a predetermined time sequence, and the receiver is configured to continuously collect the voltage signals of each set of receiving electrode groups.

[0036] During the measurement process, two operators simultaneously move along the survey line, one carrying the first carrier panel ④ and the other carrying the second carrier panel. They measure according to the preset transmission and reception positions. Upon arrival, they couple the transmitting electrode group ① and the receiving electrode group to the ground and begin data acquisition. This eliminates the need for cumbersome cable laying, effectively reducing the manpower, material resources, and workload required for deploying shallow electrical exploration equipment. During acquisition, the transmitter ③ first uses one set of transmitting electrode group ① to transmit current. After a period of time, it switches to another set of transmitting electrode group ① to transmit current. During this process, the receiver continuously acquires the voltage signals from all receiving electrode groups. This allows each measuring point to measure multiple sets of data from different transmission and reception orientations, ensuring that subsequent data processing and inversion avoid the influence of shallow three-dimensional electrical anomalies and anisotropy.

[0037] Example 2

[0038] This embodiment provides a multi-directional shallow electrical resistivity tomography (EDT) device, including: a first support panel ④ and a second support panel. Both the first and second support panels are disc-shaped structures with a diameter of 1m, facilitating manual transport and field deployment. A four-channel transmitter ③ is positioned at the center of the first support panel ④, and a four-channel receiver is positioned at the center of the second support panel. This arrangement ensures a stable center of gravity for the device, making it easy to carry and operate. Four sets of transmitting electrodes ① (A1-B1, A2-B2, A3-B3, A4-B4) are arranged on the first support panel ④, distributed symmetrically in four directions. Similarly, four sets of receiving electrodes ① (M1-N1, M2-N2, M3-N3, M4-N4) are arranged on the second support panel, also distributed symmetrically in four directions. Figure 2As shown, eight holes are equally spaced on the front edges of the first and second support panels ④ to hold screws, calipers, or other devices for fixing the electrodes. Four sets of transmitting electrode groups ①, used for transmitting current signals, are fixed to the bottom surface of the first support panel ④, and four sets of receiving electrode groups, used for receiving voltage signals, are fixed to the bottom surface of the second support panel. The transmitting electrode groups ① can be made of copper electrodes, which have good conductivity and can effectively inject current into the ground. Their shape can be rod-shaped for easy insertion into the ground. Alternatively, plate-shaped electrodes can be used to increase the contact area with the ground, allowing the current to be distributed more evenly underground. The receiving electrode groups can be made of non-polarized electrodes, which can reduce the influence of electrode polarization on the measurement results and improve measurement accuracy. The non-polarized electrodes can be cylindrical for easy insertion into the ground.

[0039] Transmitter ③ is connected to four sets of transmitting electrode groups ① via wires to inject current into the ground. Receivers are connected to four sets of receiving electrode groups via wires to collect voltage signals. Both transmitter ③ and receiver integrate positioning and azimuth detection devices. The positioning device determines the coordinates of transmitter ③ and receiver, while the azimuth detection device determines the azimuth angle of the corresponding transmitting electrode group ① / receiving electrode group. Based on the coordinates of transmitter ③ / receiver and the azimuth angle of transmitting electrode group ① / receiving electrode group, the coordinates of transmitting electrode group ① / receiving electrode group can be determined for accurate calculation of apparent resistivity and apparent polarizability. The positioning device is a real-time dynamic differential positioning module (RTK), which has high-precision positioning capabilities and can accurately determine the device's location in the field. The azimuth detection device is a three-component magnetoresistive sensor, which can sense the direction of the Earth's magnetic field to determine the device's orientation. This information is crucial for accurately calculating apparent resistivity and apparent polarizability, as these are closely related to the position and orientation of the electrodes.

[0040] Transmitter ③ is configured to sequentially switch each group of transmitting electrode groups ① to output current according to a predetermined time sequence, while the receiver is configured to continuously acquire the voltage signals of each group of receiving electrode groups. For example, transmitting electrode group ① (A1-B1) transmits a current signal, and all four receiving electrode groups measure simultaneously. After time T, transmitting electrode group ① (A2-B2) transmits, and all four receiving electrode groups measure simultaneously, and so on. After time 4T, the transmission and measurement of all four groups of transmitting electrode groups ① are completed, and then the measurement of the next measurement point is performed. Each measurement point can measure 4×4=16 sets of data from different transmission and reception orientations, ensuring subsequent data processing and inversion, and avoiding the influence of shallow three-dimensional electrical anomalies and anisotropy.

[0041] Example 3

[0042] This embodiment provides a multi-directional shallow electrical resistivity tomography (EDT) device, comprising: a first support panel ④ and a second support panel, both of which are disc-shaped structures. A multi-channel transmitter ③ is positioned at the center of the first support panel ④, and a multi-channel receiver is positioned at the center of the second support panel. The transmitter ③ and receiver each integrate a positioning device and an azimuth angle detection device. The positioning device determines the coordinates of the transmitter ③ and receiver, and the azimuth angle detection device determines the azimuth angle of the corresponding transmitting electrode group ① / receiving electrode group. Multiple transmitting electrode groups ① are arranged in a circular array along the edge of the first support panel ④, and multiple receiving electrode groups are arranged in a circular array along the edge of the second support panel. This distribution ensures that the electrode groups are uniformly distributed in the circumferential direction, enabling the injection of current and the acquisition of voltage signals into the ground from multiple directions, further improving the comprehensiveness of the exploration.

[0043] The conductive paths ② between the transmitting electrode group ① and the transmitter ③, and between the receiving electrode group and the receiver, all use wires with a cross-sectional area ≥ 1.5 mm² to ensure that the transmitter ③ can transmit at a higher power. In this way, the first carrier panel ④ and the second carrier panel can still measure a stable secondary voltage when they are far apart, and stable induced polarization parameters such as apparent polarization can be obtained.

[0044] Example 4

[0045] This embodiment provides a multi-directional shallow electrical resistivity tomography (EDT) apparatus, comprising: a first support panel ④ and a second support panel, both of which are disk-shaped structures. A multi-channel transmitter ③ is disposed at the center of the first support panel ④, and a multi-channel receiver is disposed at the center of the second support panel. The transmitter ③ and receiver each integrate a positioning device and an azimuth angle detection device. The positioning device determines the coordinates of the transmitter ③ and receiver, and the azimuth angle detection device determines the azimuth angle of the corresponding transmitting electrode group ① / receiving electrode group. Multiple transmitting electrode groups ① are disposed on the first support panel ④ and arranged in a circular array along the edge of the first support panel ④. Multiple receiving electrode groups are disposed on the second support panel and arranged in a circular array along the edge of the second support panel.

[0046] Transmitter ③ and receiver are each equipped with a wireless communication module. The coordinate signals collected by the positioning device and the azimuth signals collected by the azimuth detection device are transmitted in real time to an external data processing device via the wireless communication module. Based on the coordinate and azimuth signals, combined with the current parameters of transmitter ③ and the voltage parameters of receiver, the external data processing device calculates the apparent resistivity and apparent polarizability of the formation. For example, the current data recorded by transmitter ③ and the voltage data recorded by receiver, the midpoint coordinates of transmitter ③ and receiver, and the azimuth angles of transmitting electrode group ① and receiving electrode group can be wirelessly transmitted back to a host computer such as a mobile phone or PC in real time. Based on the midpoint coordinates of transmitter ③ and receiver and the electrode azimuth angles, the coordinates of each electrode are obtained, and the device coefficients of the resistivity method are calculated, further calculating the apparent resistivity and apparent polarizability. The host computer can also display and analyze the data in real time, draw a pseudo-section diagram of apparent resistivity, and obtain the underground electrical anomalies.

[0047] The specific measurements are as follows:

[0048] During the measurement process, two operators simultaneously move along the measurement line. One operator carries the first carrier panel ④, and the other carries the second carrier panel. The first carrier panel ④ integrates the transmitter ③ and four sets of transmitting electrode groups, while the second carrier panel integrates the receiver and four sets of receiving electrode groups. Measurements are performed according to the pre-set transmitting and receiving positions. After arriving at the positions, the transmitting electrode group ① and the receiving electrode group are coupled to the ground, and data acquisition begins.

[0049] Starting from T0, transmitter ③ transmits a current with frequency F, amplitude I, and duration T using electrode A1-B1. The receiver's four channels simultaneously measure the potential difference between four sets of receiving electrodes: M1-N1, M2-N2, M3-N3, and M4-N4. After an interval of ΔT, transmitter ③ transmits a current with frequency F, amplitude I, and duration T using electrode A2-B2. The receiver's four channels simultaneously measure this, and so on, until the transmission of all four sets of transmitting electrodes is completed.

[0050] A host computer, such as a mobile phone or tablet, can wirelessly connect to the transmitter ③ and the receiver to acquire current data recorded by the transmitter ③, voltage data recorded by the receiver, as well as the coordinates of the transmitter ③ and the receiver, and the azimuth parameters of each electrode. Based on the acquired data, the host computer calculates primary voltage, secondary voltage, device coefficient, apparent resistivity, apparent polarizability, and other data. Through this process, the aforementioned device can be used to complete multi-directional shallow resistivity method exploration.

[0051] Since the transmitter ③ and transmitting electrode group ① are integrated on the first support panel ④, and the receiver and receiving electrode group are integrated on the second support panel, there is no need to lay cumbersome cables, effectively reducing the manpower, material resources, and workload of setting up shallow electrical exploration equipment. During the acquisition process, the transmitter ③ first uses one set of transmitting electrode group ① to transmit current, and after a period of time, switches to another set of transmitting electrode group ① to transmit current. During this process, the receiver continuously acquires the voltage signals of all receiving electrode groups. In this way, each measuring point can measure multiple sets of data from different transmission and reception orientations, ensuring that subsequent data processing and inversion avoid the influence of shallow three-dimensional electrical anomalies and anisotropy. Furthermore, since the transmitter ③ and transmitting electrode group ① are integrated together on the first support panel ④, it is convenient to use thick cables to connect the transmitter ③ and transmitting electrode group ①, ensuring that the transmitter ③ can transmit at a higher power. In this way, the first support panel ④ and the second support panel can still measure stable secondary voltages even when they are far apart, and stable induced polarization parameters such as apparent polarizability can be obtained.

[0052] The above embodiments are only used to illustrate the technical solutions of this application, and are not intended to limit them. Although this application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of this application, and should all be included within the protection scope of this application.

Claims

1. A multi-directional shallow electrical resistivity tomography (EPT) exploration device, characterized in that, include: First load-bearing panel and second load-bearing panel; The first carrier panel is equipped with a transmitter and at least two sets of transmitting electrode groups, and the second carrier panel is equipped with a receiver and at least two sets of receiving electrode groups. The first and second carrier panels are configured to be carried by an operator and moved along the measurement line during the measurement process, and no connecting cable needs to be laid between the first and second carrier panels. The transmitter is connected to the transmitting electrode groups for injecting current into the ground, and the receiver is connected to the receiving electrode groups for acquiring voltage signals. The conductive paths between the transmitting electrode group and the transmitter, and between the receiving electrode group and the receiver, use wires with a cross-sectional area ≥1.5mm². The transmitter and receiver each integrate a positioning device and an azimuth angle detection device. The positioning device is a real-time dynamic differential positioning module used to locate the coordinates of the transmitter and receiver. The azimuth angle detection device is a three-component magnetoresistive sensor used to determine the azimuth angle of the transmitting electrode group and the receiving electrode group. The transmitter and receiver are each equipped with a wireless communication module. The coordinate signals collected by the positioning device and the azimuth angle signals collected by the azimuth angle detection device are transmitted in real-time to an external data processing device through the wireless communication module. The coordinates of the corresponding transmitting electrode group / receiving electrode group are determined by the positioning device and the azimuth angle detection device. The external data processing device calculates the spatial coordinates of each transmitting electrode group and receiving electrode group in real time based on the coordinate signal and the azimuth angle signal. It also calculates the apparent resistivity and apparent polarizability of the formation by combining the current parameters of the transmitter and the voltage parameters of the receiver. The transmitter is configured to switch each transmitting electrode group to output current in a predetermined sequence. The receiver is configured to continuously collect the voltage signals of each receiving electrode group.

2. The multi-directional shallow electrical resistivity tomography apparatus according to claim 1, characterized in that: The first support panel and the second support panel are both disc-shaped structures.

3. The multi-directional shallow electrical resistivity tomography apparatus according to claim 2, characterized in that: The transmitter is located at the center of the first carrier panel, and the receiver is located at the center of the second carrier panel.

4. The multi-directional shallow electrical resistivity tomography apparatus according to claim 3, characterized in that: Both the transmitting electrode group and the receiving electrode group are arranged in a ring array along the edges of the corresponding first and second carrier panels.

5. The multi-directional shallow electrical resistivity tomography apparatus according to claim 4, characterized in that: The transmitting electrode group comprises four groups and is distributed in four symmetrical positions on the first carrier panel, and the receiving electrode group comprises four groups and is distributed in four symmetrical positions on the second carrier panel.

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