Electromagnetic observation method and device based on electromagnetic field equivalent impedance

Abstract

The invention relates to an electromagnetic observation method and device based on electromagnetic field equivalent impedance, and the method comprises the steps: selecting a construction region of a detection task as a detection region according to a preset detection task demand; measuring points are arranged in the measuring area according to the detection task and a preset lateral resolution requirement; the method comprises the following steps: acquiring position topographic information of a measurement area, performing field source layout of an artificial source electromagnetic method according to the position topographic information, and acquiring horizontal electric field component data and orthogonal horizontal magnetic field component data at measurement points; calculating horizontal total magnetic field data according to the orthogonal horizontal magnetic field component data, and calculating equivalent impedance according to the horizontal electric field component data and the horizontal total magnetic field data; and calculating the wide-azimuth apparent resistivity according to the equivalent impedance. The observable range of the artificial source electromagnetic method is expanded, and the flexibility of measuring point data acquisition is improved.

Description

Technical Field

[0001] The present invention belongs to the field of geophysical exploration, and in particular relates to an electromagnetic observation method and device based on electromagnetic field equivalent impedance. Background Art

[0002] Lead wires from the transmitting system consisting of the generator and the instrument are grounded at A and B respectively, forming a loop with the earth. A and B are respectively composed of several electrodes, and the material of the electrodes is generally aluminum plate, or copper rod, etc. Figure 1 The schematic diagram of the traditional observation device for observation is shown in the figure. The current is sent underground through A and B, which is called the field source (i.e. the source of the electromagnetic field). A rectangular coordinate system is established with the midpoint of the field source as the origin, where x represents parallel to AB, y is perpendicular to AB, and z is perpendicular to the surface downward.

[0003] The artificial source electromagnetic method sends currents of different frequencies into the ground through a field source, then collects electromagnetic field signals of the same frequency at a distance and analyzes the signals to obtain the properties of the underground medium.

[0004] The electric field components are collected by leading out wires from the measuring instrument and grounding them on both sides of the measuring point to form a potential difference measuring device. The midpoint of the line connecting the grounding points is the measuring point, and the electric field can be calculated from the measured potential difference. The angle between the line connecting the two grounding points and the x-axis represents the difference in the electric field components, such as Ex represents an angle of 0, 180 or 360 degrees, and Ey represents an angle of 90 or 270 degrees. The electric field only has horizontal components, and only the changes in the horizontal direction, that is, the xoy plane, need to be considered.

[0005] The magnetic field components are collected by directly measuring at the measuring point through magnetic field sensors (magnetic bars, fluxgates, etc.). The angle between the direction of the magnetic field sensor and the x-axis represents the magnetic field component, which is the same as observing the electric field. The magnetic field has three directional components. On the one hand, it is necessary to consider the changes in the horizontal direction, and on the other hand, it is necessary to consider the changes in the vertical direction, that is, three-dimensional space.

[0006] When collecting electromagnetic field signals, the observation device of the conventional artificial source electromagnetic method can only collect the field strength within a specific azimuth of the field source (60 degrees on both sides), and can only collect specific electromagnetic field components at the measuring point, including the electric field component E x 、E y , magnetic field component H x , H y , H z Fifth, traditional observation devices have low utilization rate of field sources. Under complex terrain conditions, on the one hand, it is difficult to select a suitable field source location, and on the other hand, it is difficult to ensure the accuracy of the electromagnetic field components, resulting in low observation accuracy or even inability to carry out observations. Summary of the invention

[0007] In order to make up for the defects of the prior art, the present invention provides an electromagnetic observation method and device based on electromagnetic field equivalent impedance.

[0008] In order to solve the above technical problems, the technical solution adopted by the present invention is: In a first aspect, an electromagnetic observation method based on electromagnetic field equivalent impedance is provided, comprising: According to the preset detection task requirements, select the construction area of ​​the detection task as the measurement area; Arrange measurement points in the measurement area according to the detection task and preset lateral resolution requirements; Obtain the location and terrain information of the survey area, and arrange the field source of the artificial source electromagnetic method according to the location and terrain information; Collect horizontal electric field component data and orthogonal horizontal magnetic field component data at the measuring point; Calculate the horizontal total magnetic field data based on the orthogonal horizontal magnetic field component data, and calculate the equivalent impedance based on the horizontal electric field component data and the horizontal total magnetic field data; The wide-azimuth apparent resistivity is calculated based on the equivalent impedance.

[0009] Furthermore, the measuring points are distributed in a linear manner, a regular mesh distribution or an irregular mesh distribution.

[0010] Furthermore, the location and terrain information of the survey area is obtained, and the field source layout of the artificial source electromagnetic method is carried out according to the location and terrain information, including: Get the survey area location of the survey area; Obtain the surrounding terrain conditions of the survey area according to the location of the survey area to obtain the location terrain information; Select the target area for the field source deployment in the survey area according to the location terrain information. There is no water in the target area and the terrain undulation does not exceed the preset severity. Based on the artificial source electromagnetic method, a transmitting system that transmits current is deployed in the target area to form a field source.

[0011] Furthermore, a transmitting system for transmitting current is arranged in the target area based on the artificial source electromagnetic method to form a field source, including: Arranging a first field source electrode and a second field source electrode in a target area based on an artificial source electromagnetic method; Connecting a transmitting instrument that generates a current of a preset frequency to the first field source electrode and the second field source electrode wire to obtain a transmitting system; The current of the preset frequency generated by the transmitting instrument is transmitted underground through the first field source electrode and the second field source electrode to form a field source.

[0012] Furthermore, horizontal electric field component data and orthogonal horizontal magnetic field component data are collected at the measuring point, including: Get the receiving and transmitting distance from the measuring point to the midpoint of the line between the first field source electrode and the second field source electroder , wherein the first field source electrode and the second field source electrode generate a current I ; Get the receiving and transmitting angle of the line connecting the measuring point and the midpoint and the line connecting the first field source electrode and the second field source electrode φ , and the electric field component angle between the measuring point and the horizontal electric field α , the horizontal electric field x The axis coincides with the line connecting the first field source electrode and the second field source electrode, and the horizontal electric field y Axis and x The axis is vertical; pass x Axial electric field component calculation formula , calculated x Axis electric field component data E x ; dL is the distance between the first field source electrode and the second field source electrode, k is the wave number, , is the circular frequency, is the magnetic permeability, is the conductivity, is the dielectric constant, represents an imaginary unit; pass y Axial electric field component calculation formula , calculated y Axis electric field component data E y ; according to x Axis electric field component data E x and y Axis electric field component data E y , calculate the horizontal electric field component data ; An orthogonal two-component magnetic sensor is used to collect first orthogonal horizontal magnetic field component data H1 and second orthogonal horizontal magnetic field component data H2 of the measuring point.

[0013] Further, the horizontal total magnetic field data is calculated based on the orthogonal horizontal magnetic field component data, and the equivalent impedance is calculated based on the horizontal electric field component data and the horizontal total magnetic field data, including: The horizontal total magnetic field data is calculated based on the first orthogonal horizontal magnetic field component data H1 and the second orthogonal horizontal magnetic field component data H2. ; The horizontal electric field component data E α Substitute the horizontal total magnetic field data H into the equivalent impedance calculation formula , the equivalent impedance Z is calculated e .

[0014] Furthermore, the wide-azimuth apparent resistivity is calculated based on the equivalent impedance, including: Based on the calculation formula of wide azimuth apparent resistivity , the equivalent impedance Z e Substituting into the formula, we can calculate the wide azimuth apparent resistivity ; is the electromagnetic effect function of the horizontal electric field, and its expression is: ; F H is the electromagnetic effect function of the horizontal total magnetic field, and its expression is: ; in, ; ; Iv , Kv Respectively v Bessel functions of the first and second kind of order.

[0015] In a second aspect, an electromagnetic observation device based on electromagnetic field equivalent impedance is provided, comprising: The measurement area selection module is used to select the construction area of ​​the detection task as the measurement area according to the preset detection task requirements; The measuring point arrangement module is used to arrange measuring points in the measuring area according to the detection task and the preset lateral resolution requirements; The field source layout module is used to obtain the location and terrain information of the survey area and to layout the field source of the artificial source electromagnetic method according to the location and terrain information; A data acquisition module, used for collecting horizontal electric field component data and orthogonal horizontal magnetic field component data at a measuring point; An equivalent impedance calculation module is used to calculate horizontal total magnetic field data according to orthogonal horizontal magnetic field component data, and to calculate equivalent impedance according to horizontal electric field component data and horizontal total magnetic field data; The electromagnetic observation module is used to calculate the wide-azimuth apparent resistivity based on the equivalent impedance.

[0016] The beneficial effects achieved by the present invention are: The electromagnetic observation method based on electromagnetic field equivalent impedance of the present invention selects the construction area of ​​the detection task as the measurement area according to the preset detection task requirements; arranges measurement points in the measurement area according to the detection task and the preset lateral resolution requirements; obtains the location terrain information of the measurement area, arranges the field source of the artificial source electromagnetic method according to the location terrain information, collects horizontal electric field component data and orthogonal horizontal magnetic field component data at the measurement point; calculates the horizontal total magnetic field data according to the orthogonal horizontal magnetic field component data; calculates the horizontal total magnetic field data according to the orthogonal horizontal magnetic field component data, calculates the equivalent impedance according to the horizontal electric field component data and the horizontal total magnetic field data; and calculates the wide azimuth apparent resistivity according to the equivalent impedance. Compared with the traditional artificial source electromagnetic method that can only collect electromagnetic field components in a specific direction at the measurement point, the present invention can be combined with the terrain to observe in any horizontal electromagnetic azimuth angle of the horizontal electric field, provides flexibility in the selection of the field source position, improves the flexibility of the measurement point when collecting data, and solves the defects of the traditional artificial source electromagnetic method, such as small observation range, strict requirements on the observation device system, and inflexibility. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 It is the observation diagram of the traditional observation device; Figure 2 It is a flow chart of the electromagnetic observation method based on electromagnetic field equivalent impedance of the present invention; Figure 3 It is a schematic diagram of electromagnetic observation based on electromagnetic field equivalent impedance of the present invention; Figure 4 is the electric field component angle of the present invention α and transmit / receive angle φ The logarithm of the horizontal electric field component data lg E Relationship diagram; Figure 5 A schematic diagram of collecting orthogonal horizontal magnetic field components at measuring points of the present invention; Figure 6 This is a structural diagram of the electromagnetic observation device based on electromagnetic field equivalent impedance of the present invention. DETAILED DESCRIPTION

[0018] The present invention will be further described below in conjunction with the accompanying drawings. The following embodiments are only used to more clearly illustrate the technical solution of the present invention, and cannot be used to limit the protection scope of the present invention.

[0019] like Figure 2 As shown, an embodiment of the present invention provides an electromagnetic observation method based on electromagnetic field equivalent impedance, comprising: 201, according to the preset detection task requirements, select the construction area of ​​the detection task as the measurement area; The preset detection task requirements include the approximate area to be detected and the target to be detected, such as rock layer, oil and gas layer, water layer, mineral, etc. After the detection task is known, the detector can know the data requirements of the detection task in advance, so according to the preset detection task requirements, the construction area of ​​the detection task can be selected as the measurement area.

[0020] 202, arranging measuring points in the measuring area according to the detection task and the preset lateral resolution requirements; Among them, after determining the scope of the survey area, it is necessary to arrange the measuring points in the survey area, and set the position and number of the measuring points according to the detection task and the preset lateral resolution requirements. In the field of electromagnetic detection, lateral resolution is the ability to distinguish the minimum distance between two adjacent geological bodies in the horizontal direction, in units of length; it is related to the arrangement of the measuring points in the horizontal direction, the nature of the source signal, and the physical properties of the detected target. The smaller the value, the higher the lateral resolution. Figure 3 It is a schematic diagram of electromagnetic observation based on electromagnetic field equivalent impedance of the present invention, wherein the distribution of measuring points is not the distribution mode of the traditional artificial source electromagnetic method, but can be linear distribution, regular mesh distribution or irregular mesh distribution.

[0021] 203, obtaining location and terrain information of the survey area, and arranging the field source of the artificial source electromagnetic method according to the location and terrain information; The specific process of field source layout is as follows: First, obtain the survey area location of the survey area. The survey area location is actually the geographical location, which can be reflected by the latitude and longitude information; Obtain the surrounding terrain conditions of the survey area according to the survey area location. The surrounding terrain conditions can be obtained by viewing the data of the geo-hydrological information database or the local map data to obtain the location terrain information; Select the target area for the field source layout in the measurement area according to the location terrain information. There is no water in the target area and the terrain fluctuation does not exceed the preset severity. Because the water area will affect the electric field, and the severe terrain fluctuation will also affect the measurement accuracy. Based on the artificial source electromagnetic method, a transmitting system that transmits current is deployed in the target area to form a field source; Figure 3 As shown, based on the artificial source electromagnetic method, the first field source electrode A and the second field source electrode B are arranged in the target area; electrode pits are dug at A and B, aluminum plates are buried, the plates are led out by wires, and salt water is poured and buried; Connect the transmitting instrument that generates the current of the preset frequency to the first field source electrode A and the second field source electrode B to obtain the transmitting system; transmit the current of the preset frequency generated by the transmitting instrument to the ground through the first field source electrode and the second field source electrode to form a field source. Figure 3It can be seen that the field source can be at any position of the measuring point, which has a wider range compared with the traditional artificial source electromagnetic method.

[0022] 204, collecting horizontal electric field component data and orthogonal horizontal magnetic field component data at the measuring point; Electromagnetic detection is to receive electromagnetic signals from underground media by arranging electrodes or sensors on the ground. Specifically, orthogonal two-component magnetic sensors are used to infer the underground geological structure. Topographic conditions, such as terrain undulations and changes in surface resistivity, will affect the propagation and reception of electromagnetic signals. Large terrain undulations will cause signal attenuation, and changes in surface resistivity will affect the propagation path and intensity of the signal. Therefore, it is necessary to obtain terrain condition information at the measuring point. The target direction of the magnetic field sensor at each measuring point is set according to the terrain condition information. For example, if the magnetic field sensor is a hollow coil, the setting direction of the coil is the target direction. The specific process of collecting horizontal electric field component data of the measuring point is as follows: like Figure 4 The electric field component angles are shown α and transmit / receive angle φ The logarithm of the horizontal electric field component data lg E If the electric field component angle is selected α and transmit / receive angle φ The corresponding horizontal electric field component data logarithm lg E If the value of is too small, the data signal-to-noise ratio will be very poor, for example Figure 4 The blue area outside the dotted line is the area that is not suitable for collecting electric field components. Therefore, the electric field component angle outside the dotted line area cannot be selected. α and transmit / receive angle φ ; Get the receiving and transmitting distance from the measuring point to the midpoint of the line between the first field source electrode and the second field source electrode r , wherein the first field source electrode and the second field source electrode generate a current I ; Get the receiving and transmitting angle of the line connecting the measuring point and the midpoint and the line connecting the first field source electrode and the second field source electrode φ , and the electric field component angle between the measuring point and the horizontal electric field α , the horizontal electric field x The axis coincides with the line connecting the first field source electrode and the second field source electrode, and the horizontal electric field y Axis and x The axis is vertical; pass x Axial electric field component calculation formula , calculated x Axis electric field component data E x ; dL is the distance between the first field source electrode and the second field source electrode,k is the wave number, , w is the circular frequency, is the magnetic permeability, is the conductivity, is the dielectric constant, represents an imaginary unit; pass y Axial electric field component calculation formula , calculated y Axis electric field component data E y ; according to x Axis electric field component data E x and y Axis electric field component data E y , calculate the horizontal electric field component data ; The process of collecting the orthogonal horizontal magnetic field component data of the measuring point is: Use an orthogonal two-component magnetic sensor to collect first orthogonal horizontal magnetic field component data H1 and second orthogonal horizontal magnetic field component data H2 of the measuring point; Figure 5 The figure shows the schematic diagram of collecting horizontal magnetic field components at the measuring point; the collected magnetic field components are determined by the direction and x The angle between the axes is determined. x The axis is determined by the line connecting the field source electrode A and the field source electrode B. Figure 5 The magnetic field collected by the two horizontal axial coils of the orthogonal two-component magnetic sensor is the orthogonal horizontal magnetic field components H1 and H2.

[0023] 205, calculating horizontal total magnetic field data according to the orthogonal horizontal magnetic field component data, and calculating equivalent impedance according to the horizontal electric field component data and the horizontal total magnetic field data; According to the above first orthogonal horizontal magnetic field component data H1 and second orthogonal horizontal magnetic field component data H2, the horizontal total magnetic field data is calculated. , the horizontal electric field component data E α Substitute the horizontal total magnetic field data H into the equivalent impedance calculation formula , the equivalent impedance Z is calculated e .

[0024] 206, the wide azimuth apparent resistivity is calculated based on the equivalent impedance.

[0025] Among them, according to the calculation formula of wide azimuth apparent resistivity , the equivalent impedance Z e Substituting into the formula, we can calculate the wide azimuth apparent resistivity ; is the electromagnetic effect function of the horizontal electric field, and its expression is: ; F H is the electromagnetic effect function of the horizontal total magnetic field, and its expression is: ; in, ; ; Iv , Kv Respectively v Bessel functions of the first and second kind of order.

[0026] The beneficial effects of the embodiments of the present invention are: According to the preset detection task requirements, the construction area of ​​the detection task is selected as the measurement area; the measurement points are arranged in the measurement area according to the detection task and the preset lateral resolution requirements; the location terrain information of the measurement area is obtained, the field source of the artificial source electromagnetic method is arranged according to the location terrain information, and the horizontal electric field component data and the horizontal magnetic field component data are collected at the measurement point; the horizontal total magnetic field data is calculated according to the orthogonal horizontal magnetic field component data, and the equivalent impedance is calculated according to the horizontal electric field component data and the horizontal total magnetic field data; the wide azimuth apparent resistivity is calculated according to the equivalent impedance. Compared with the traditional artificial source electromagnetic method that can only collect electromagnetic field components in a specific direction at the measurement point, the present invention can be combined with the terrain to observe in any horizontal electromagnetic azimuth angle of the horizontal electric field, which provides flexibility in the selection of the field source position, improves the flexibility of the measurement point when collecting data, and solves the defects of the traditional artificial source electromagnetic method, such as small observation range, strict requirements on the observation device system, and inflexibility.

[0027] In combination with the electromagnetic observation method based on electromagnetic field equivalent impedance described in the above embodiments, an electromagnetic observation system based on electromagnetic field equivalent impedance is described below through an embodiment.

[0028] like Figure 6 As shown, an embodiment of the present invention provides an electromagnetic observation device based on electromagnetic field equivalent impedance, comprising: The measurement area selection module 601 is used to select the construction area of ​​the detection task as the measurement area according to the preset detection task requirements; The measuring point arrangement module 602 is used to arrange measuring points in the measuring area according to the detection task and the preset lateral resolution requirement; The field source layout module 603 is used to obtain the location and terrain information of the survey area and to layout the field source of the artificial source electromagnetic method according to the location and terrain information; The data acquisition module 604 is used to collect horizontal electric field component data and orthogonal horizontal magnetic field component data at the measuring point; An equivalent impedance calculation module 605 is used to calculate horizontal total magnetic field data according to the orthogonal horizontal magnetic field component data, and to calculate equivalent impedance according to the horizontal electric field component data and the horizontal total magnetic field data; The electromagnetic observation module 606 is used to calculate the wide-azimuth apparent resistivity based on the equivalent impedance.

[0029] The beneficial effects of the embodiments of the present invention are: The survey area selection module 601 selects the construction area of ​​the survey task as the survey area according to the preset survey task requirements; the survey point arrangement module 602 arranges the survey points in the survey area according to the survey task and the preset lateral resolution requirements; the field source arrangement module 603 obtains the location terrain information of the survey area, and arranges the field source of the artificial source electromagnetic method according to the location terrain information, and the field source is used to emit current; the data acquisition module 604 collects horizontal electric field component data and orthogonal horizontal magnetic field component data at the survey point; the equivalent impedance calculation module 605 calculates the horizontal total magnetic field data according to the orthogonal horizontal magnetic field component data, and calculates the equivalent impedance according to the horizontal electric field component data and the horizontal total magnetic field data; the electromagnetic observation module 606 calculates the wide azimuth apparent resistivity according to the equivalent impedance. Compared with the traditional artificial source electromagnetic method that can only collect electromagnetic field components in a specific direction at the survey point, the present invention can combine the terrain to observe in any horizontal electromagnetic azimuth angle of the horizontal electric field, provide flexibility in the selection of the field source position, improve the flexibility of the survey point when collecting data, and solve the defects of the traditional artificial source electromagnetic method, such as small observation range, strict requirements on the observation device system, and inflexibility.

[0030] It will be appreciated by those skilled in the art that embodiments of the present invention may be provided as methods, systems, or computer program products. Therefore, the present invention may take the form of a complete hardware embodiment, a complete software embodiment, or an embodiment combining software and hardware. Furthermore, the present invention may take the form of a computer program product implemented on one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) containing computer-usable program code.

[0031] The present invention is described with reference to flowcharts and / or block diagrams of methods, devices (systems), and computer program products according to embodiments of the present invention. It should be understood that each process and / or block in the flowchart and / or block diagram, as well as the combination of processes and / or blocks in the flowchart and / or block diagram, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, a special-purpose computer, an embedded processor, or other programmable data processing device to produce a machine, so that the instructions executed by the processor of the computer or other programmable data processing device generate instructions for implementing the processes in the flowchart and / or block diagram. Figure 1 A process or multiple processes and / or boxes Figure 1 A device that provides the functions specified in a block or multiple blocks.

[0032] These computer program instructions may also be stored in a computer-readable memory capable of directing a computer or other programmable data processing device to operate in a specific manner, so that the instructions stored in the computer-readable memory produce an article of manufacture comprising an instruction device, which implements the process Figure 1 A process or multiple processes and / or boxes Figure 1 A function specified in one or more boxes.

[0033] These computer program instructions can also be loaded onto a computer or other programmable data processing device so that a series of operating steps are executed on the computer or other programmable device to produce a computer-implemented process, thereby providing instructions for implementing the process. Figure 1 A process or multiple processes and / or boxes Figure 1 The steps for the functions specified in one or more boxes.

[0034] The above are merely embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention are included in the scope of the claims of the present invention to be approved.

Claims

1. An electromagnetic observation method based on electromagnetic field equivalent impedance, characterized in that: include: According to the preset detection task requirements, select the construction area of ​​the detection task as the measurement area; Arrange measurement points in the measurement area according to the detection task and the preset lateral resolution requirement; Acquiring location topographic information of the survey area, and arranging the field source of the artificial source electromagnetic method according to the location topographic information; Collecting horizontal electric field component data and orthogonal horizontal magnetic field component data at the measuring point; Calculate the horizontal total magnetic field data according to the orthogonal horizontal magnetic field component data, and calculate the equivalent impedance according to the horizontal electric field component data and the horizontal total magnetic field data; The wide-azimuth apparent resistivity is calculated based on the equivalent impedance.

2. The electromagnetic observation method based on electromagnetic field equivalent impedance according to claim 1, characterized in that: The measuring points are distributed in a linear manner, a regular mesh distribution or an irregular mesh distribution.

3. The electromagnetic observation method based on electromagnetic field equivalent impedance according to claim 1, characterized in that: The step of obtaining the location topographic information of the survey area and arranging the field source of the artificial source electromagnetic method according to the location topographic information includes: Acquire a measurement area position of the measurement area; Acquire the surrounding terrain conditions of the survey area according to the location of the survey area to obtain location terrain information; Selecting a target area for field source deployment in the survey area according to the location terrain information, wherein there is no water area and the terrain undulation does not exceed a preset severity; Based on the artificial source electromagnetic method, a transmitting system for transmitting current is arranged in the target area to form a field source.

4. The electromagnetic observation method based on electromagnetic field equivalent impedance according to claim 3, characterized in that: The transmitting system for arranging the transmitting current in the target area based on the artificial source electromagnetic method to form a field source includes: Arranging a first field source electrode and a second field source electrode in the target area based on an artificial source electromagnetic method; Connecting a transmitting instrument that generates a current of a preset frequency to the first field source electrode and the second field source electrode wires to obtain a transmitting system; The current of the preset frequency generated by the transmitting instrument is transmitted underground through the first field source electrode and the second field source electrode to form a field source.

5. The electromagnetic observation method based on electromagnetic field equivalent impedance according to claim 4, characterized in that: The collecting of horizontal electric field component data and orthogonal horizontal magnetic field component data at the measuring point comprises: Obtain the receiving and transmitting distance from the measuring point to the midpoint of the line connecting the first field source electrode and the second field source electrode r , wherein the first field source electrode and the second field source electrode generate a current I ; Obtaining the transmitting and receiving angles of the line connecting the measuring point and the midpoint and the connecting line between the first field source electrode and the second field source electrode φ , and the electric field component angle between the measuring point and the horizontal electric field α , the horizontal electric field x The axis coincides with the line connecting the first field source electrode and the second field source electrode, and the horizontal electric field y Axis and x The axis is vertical; pass x Axial electric field component calculation formula , calculated x Axis electric field component data E x ; dL is the distance between the first field source electrode and the second field source electrode, k is the wave number, , is the circular frequency, is the magnetic permeability, is the conductivity, is the dielectric constant, represents an imaginary unit; pass y Axial electric field component calculation formula , calculated y Axis electric field component data E y ; According to the x Axis electric field component data E x and stated y Axis electric field component data E y , calculate the horizontal electric field component data ; An orthogonal two-component magnetic sensor is used to collect the first orthogonal horizontal magnetic field component data H1 and the second orthogonal horizontal magnetic field component data H2 of the measuring point.

6. The electromagnetic observation method based on electromagnetic field equivalent impedance according to claim 5, characterized in that: The calculating of the horizontal total magnetic field data according to the orthogonal horizontal magnetic field component data, and the calculating of the equivalent impedance according to the horizontal electric field component data and the horizontal total magnetic field data, include: The horizontal total magnetic field data H1 is calculated based on the first orthogonal horizontal magnetic field component data H1 and the second orthogonal horizontal magnetic field component data H2. ; The horizontal electric field component data E α Substitute the horizontal total magnetic field data H into the equivalent impedance calculation formula , the equivalent impedance Z is calculated e .

7. The electromagnetic observation method based on electromagnetic field equivalent impedance according to claim 6, characterized in that: The step of calculating the wide-azimuth apparent resistivity according to the equivalent impedance includes: Based on the calculation formula of wide azimuth apparent resistivity , the equivalent impedance Z e Substituting into the formula, we can calculate the wide azimuth apparent resistivity ; Said is the electromagnetic effect function of the horizontal electric field, and its expression is: ； Said F H is the electromagnetic effect function of the horizontal total magnetic field, and its expression is: ； Among them, the ; Said ; Said Iv , Kv Respectively v Bessel functions of the first and second kind of order.

8. An electromagnetic observation device based on electromagnetic field equivalent impedance, characterized in that: include: The measurement area selection module is used to select the construction area of ​​the detection task as the measurement area according to the preset detection task requirements; A measuring point arrangement module, used to arrange measuring points in the measuring area according to the detection task and the preset lateral resolution requirement; A field source layout module, used to obtain the location and topographic information of the survey area, and to layout the field source of the artificial source electromagnetic method according to the location and topographic information; A data acquisition module, used for acquiring horizontal electric field component data and orthogonal horizontal magnetic field component data at the measuring point; An equivalent impedance calculation module, used for calculating horizontal total magnetic field data according to the orthogonal horizontal magnetic field component data, and calculating equivalent impedance according to the horizontal electric field component data and the horizontal total magnetic field data; The electromagnetic observation module is used to calculate the wide-azimuth apparent resistivity according to the equivalent impedance.

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