Ground multi-dimensional transient electromagnetic detection method

Abstract

The invention belongs to the technical field of transient electromagnetism in geophysical methods, and particularly relates to a ground multi-dimensional transient electromagnetic detection method which comprises the following steps: S1, planning and recording a measuring point network; in the step S1, before detection work is carried out, a measuring point network needs to be planned in advance, and measuring point coordinates in the network need to be recorded. S2, carrying out one-dimensional, two-dimensional and three-dimensional detection according to detection requirements; in the step S2, the specific steps are as follows: S2-1, one-dimensional detection adopts a point-by-point measurement mode, and data acquisition is completed point by point. And S2-2, two-dimensional detection adopts a line-by-line measurement mode, signals are transmitted and received at the same time through signal synchronization, and after arrangement data acquisition is completed, the two-dimensional detection is completed. And S2-3, when three-dimensional detection is carried out, all the measuring points are synchronously transmitted and received. According to the invention, one-dimensional, two-dimensional and three-dimensional transient electromagnetic detection can be realized, and the advantages of one-dimensional to three-dimensional detection are considered; no matter how many nodes are selected, a mode of simultaneously transmitting and receiving signals is adopted.

Description

Technical Field

[0001] The invention belongs to the technical field of transient electromagnetic technology in geophysical methods, and in particular relates to a ground multi-dimensional transient electromagnetic detection method. Background Art

[0002] According to the time domain electromagnetic field theory, transient electromagnetic exploration has three detection modes: one-dimensional, two-dimensional, and three-dimensional. For a ground measuring point network with m rows and n columns (m measuring lines, each measuring line has n measuring points), one-dimensional detection measures all ground measuring points point by point, that is, signals are transmitted and received at one measuring point, and after completing the data collection of the measuring point, data collection of the next measuring point is carried out ( Figure 1 ), one-dimensional detection can only reflect the vertical changes in the electrical properties of the underground medium below a single measuring point. Two-dimensional detection takes a survey line as an arrangement, arranges transmitting and receiving antennas at all measuring points of the arrangement, and transmits and receives signals at the same time through signal synchronization. After completing the data collection of the arrangement, the data collection of the next arrangement (survey line) is carried out ( Figure 2 ). The two-dimensional detection result is the two-dimensional profile information below the survey line, which can show the lateral and longitudinal changes in the electrical properties of the medium in the profile. Since the actual geological structure is three-dimensional, only by using the synchronous transmission-reception method and performing three-dimensional detection on all the measuring points in the ground measuring point network can the real information of the underground three-dimensional geological structure be obtained ( Figure 3 At present, due to the limitations of the ground working environment and instrument equipment conditions, ground transient electromagnetic detection uses a one-dimensional detection method. Summary of the invention

[0003] The purpose of the present invention is to provide a ground multi-dimensional transient electromagnetic detection method, which can realize one-dimensional, two-dimensional and three-dimensional transient electromagnetic detection, taking into account the advantages of one-dimensional to three-dimensional detection; regardless of the number of primary nodes selected, the signal simultaneous transmission and simultaneous reception mode is adopted.

[0004] The technical solution adopted by the present invention is as follows:

[0005] A ground multi-dimensional transient electromagnetic detection method, the detection method comprising the following steps:

[0006] S1: Plan the measuring point network and record the measuring points;

[0007] In S1, before the detection work is carried out, it is necessary to plan the measuring point network in advance and record the coordinates of the measuring points in the network.

[0008] S2: Perform one-dimensional, two-dimensional and three-dimensional detection according to detection requirements;

[0009] In S2, the specific detection steps are as follows:

[0010] S2-1: When performing one-dimensional detection, a point-by-point measurement method is used to complete data collection at each measuring point point by point;

[0011] S2-2: When performing two-dimensional detection, a line-by-line measurement method is adopted. Through signal synchronization, signals are transmitted and received at the same time. After completing the data collection of the arrangement, the data collection of the next arrangement is carried out;

[0012] S2-3: When performing three-dimensional detection, adopt the synchronous measurement method of all measuring points, synchronously transmit and receive all measuring points in the measurement network, and obtain the measurement information of all measuring points at one time.

[0013] S3: Process the collected detection data.

[0014] In S3, the one-dimensional, two-dimensional and three-dimensional detection data can be processed and visualized using transient electromagnetic processing technology, and combined with the obtained geological and drilling data for comprehensive interpretation.

[0015] The technical effects achieved by the present invention are:

[0016] The ground multi-dimensional transient electromagnetic detection method of the present invention adopts an array measurement network design, and can realize one-dimensional, two-dimensional and three-dimensional transient electromagnetic detection by designing and planning the node array in the measurement network.

[0017] The ground multi-dimensional transient electromagnetic detection method of the present invention has the characteristics that one-dimensional detection reflects the vertical changes in the electrical properties of the underground medium below the measuring point, two-dimensional detection reflects the lateral and longitudinal changes in the electrical properties of the medium below the measuring line, and three-dimensional detection can obtain real information on the underground three-dimensional geological structure. The present invention can take into account the advantages of one-dimensional to three-dimensional detection, reflect one-dimensional, two-dimensional, and three-dimensional geological structures, and is suitable for different geological detection tasks.

[0018] The ground multi-dimensional transient electromagnetic detection method of the present invention can generate several combinations according to actual detection needs. Combined with actual working conditions, multiple device forms can be determined. There are many options, and it can be connected with drones, robots and other carrying platforms. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 It is a schematic diagram of a measuring point network and one-dimensional detection according to an embodiment of the present invention;

[0020] Figure 2 is a schematic diagram of a measuring point network and two-dimensional detection according to an embodiment of the present invention;

[0021] Figure 3 is a schematic diagram of a measuring point network and three-dimensional detection according to an embodiment of the present invention;

[0022] Figure 4 Schematic diagram of a ground multi-dimensional transient electromagnetic detection method according to an embodiment of the present invention;

[0023] Figure 5 It is a schematic diagram of one-dimensional, two-dimensional and three-dimensional detection results of an embodiment of the present invention. DETAILED DESCRIPTION

[0024] In order to make the purpose and advantages of the present invention more clearly understood, the present invention is specifically described below in conjunction with embodiments. It should be understood that the following text is only used to describe one or several specific embodiments of the present invention, and does not strictly limit the scope of protection of the specific claims of the present invention.

[0025] like Figure 1-Figure 4 As shown, a ground multi-dimensional transient electromagnetic detection method, the detection method comprises the following steps:

[0026] S1: Plan the measuring point network and record the measuring points;

[0027] In S1, before the detection work is carried out, it is necessary to plan the measuring point network in advance and record the coordinates of the measuring points in the network.

[0028] S2: Perform one-dimensional, two-dimensional and three-dimensional detection according to detection requirements;

[0029] In S2, the specific detection steps are as follows:

[0030] S2-1: When performing one-dimensional detection, a point-by-point measurement method is used to complete data collection at each measuring point point by point;

[0031] S2-2: When performing two-dimensional detection, a line-by-line measurement method is adopted. Through signal synchronization, signals are transmitted and received at the same time. After completing the data collection of the arrangement, the data collection of the next arrangement is carried out;

[0032] S2-3: When performing three-dimensional detection, adopt the synchronous measurement method of all measuring points, synchronously transmit and receive all measuring points in the measurement network, and obtain the measurement information of all measuring points at one time.

[0033] S3: Process the collected detection data.

[0034] In S3, one-dimensional, two-dimensional and three-dimensional detection data can be processed and visualized using transient electromagnetic processing technology, and combined with the obtained geological and drilling data for comprehensive interpretation.

[0035] like Figure 5As shown in the figure, one-dimensional detection is a single-point measurement, and its result reflects the one-dimensional structure of the underground medium, and is displayed as a resistivity curve that changes with depth. Two-dimensional detection is a synchronous measurement of all measuring points in the entire survey line, and its result reflects the two-dimensional structure of the underground medium, and is displayed as a resistivity profile. Three-dimensional detection is a synchronous measurement of all measuring points in the measurement network, and its result reflects the three-dimensional structure of the underground medium, and is displayed as a three-dimensional resistivity model.

[0036] The present invention proposes a ground multi-dimensional transient electromagnetic detection method, which is based on the transient electromagnetic field theory. By designing and planning the node array in the measurement network, a single node, the entire measurement line and all nodes are selected according to the actual detection task for synchronous transmission and reception, so as to realize one-dimensional, two-dimensional and three-dimensional transient electromagnetic detection, taking into account the advantages of one-dimensional to three-dimensional detection, while the current technical scheme can only realize one-dimensional detection. Regardless of the number of nodes selected at one time, the signal is transmitted and received simultaneously. Through the node-type measurement network design, the measurement node array can be flexibly planned according to the detection depth requirements to realize variable-dimensional measurement from one dimension to three dimensions. At the same time, by changing the size and weight of the transmitting-receiving antenna, it can be connected with the carrying platforms such as drones and robots.

[0037] The above is only a preferred embodiment of the present invention. It should be noted that, for those skilled in the art, several improvements and modifications can be made without departing from the principles of the present invention, and these improvements and modifications should also be considered as the protection scope of the present invention. The structures, devices and operating methods not specifically described and explained in the present invention shall be implemented according to the conventional means in the art unless otherwise specified and limited.

Claims

1. A ground multi-dimensional transient electromagnetic detection method, characterized in that: The detection method comprises the following steps: S1: Plan the measuring point network and record the measuring points; S2: Perform one-dimensional, two-dimensional and three-dimensional detection according to detection requirements; S3: Process the collected detection data.

2. A ground multi-dimensional transient electromagnetic detection method according to claim 1, characterized in that: In S1, before the detection work is carried out, it is necessary to plan the measuring point network in advance and record the coordinates of the measuring points in the network.

3. A ground multi-dimensional transient electromagnetic detection method according to claim 1, characterized in that: In S2, the specific detection steps are as follows: S2-1: When performing one-dimensional detection, a point-by-point measurement method is used to complete data collection at each measuring point one by one; S2-2: When performing two-dimensional detection, a line-by-line measurement method is adopted. Through signal synchronization, signals are transmitted and received at the same time. After completing the data collection of the arrangement, the data collection of the next arrangement is carried out; S2-3: When performing three-dimensional detection, adopt the synchronous measurement method of all measuring points, synchronously transmit and receive all measuring points in the measurement network, and obtain the measurement information of all measuring points at one time.

4. A ground multi-dimensional transient electromagnetic detection method according to claim 1, characterized in that: In S3, the one-dimensional, two-dimensional and three-dimensional detection data can be processed and visualized using transient electromagnetic processing technology, and combined with the obtained geological and drilling data for comprehensive interpretation.

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