A method for identifying hidden troubles of earth and rockfill dams through multi-source geophysical data information fusion interpretation

Abstract

This invention discloses a method for identifying hidden dangers in earth-rock embankments based on the fusion and interpretation of multi-source geophysical data. It relates to the field of geophysical exploration for hidden dangers in water conservancy projects. The method involves acquiring and processing structural profile data of earth-rock embankments; obtaining the distribution of internal defect information and analyzing the anomaly response mechanisms of typical hidden defects in earth-rock embankments using high-density electrical resistivity tomography (EDS) and ground-penetrating radar (GPR), thus characterizing the anomaly information; constructing a regularized grid using Kriging spatial interpolation to enhance data spatial continuity; performing spatial registration; and fusing the registered multi-source geophysical anomaly information at the feature level. Combined with prior knowledge of the geological medium of earth-rock embankments, a method for identifying internal defects in earth-rock embankment structures based on the fusion and interpretation of multi-source geophysical data is established. The defect identification method provided by this invention achieves high-precision interpretation of internal defect information in earth-rock embankments, completing the accurate identification of structural defects across the entire chain of hidden danger detection information.

Description

Technical Field

[0001] This invention relates to the field of geophysical exploration for potential hazards in water conservancy projects, and in particular to a method for identifying potential hazards in earth-rock dams through the fusion and interpretation of multi-source geophysical data. Background Technology

[0002] Earth-rock dams are core infrastructure for flood control, disaster reduction, and water resource regulation. A large proportion of my country's current engineering projects are earth-rock dams built between the 1950s and 1970s, many of which suffer from low construction standards, inadequate filling, and insufficient construction quality control, resulting in prominent internal defects such as voids, cracks, and seepage channels.

[0003] Against the backdrop of global climate change, extreme weather events such as torrential rains and floods exceeding standard levels occur frequently, leading to engineering hazards such as seepage and collapses caused by hidden geological defects. These hazards seriously threaten people's lives and property and regional ecological stability. Typical hidden geological defects such as voids, water-filled cracks, seepage channels, loose areas, and soil cavities are concealed disaster-causing factors in earth-rock dam engineering. Common methods for identification include high-density electrical resistivity prospecting (EDS) and ground-penetrating radar (GPR). EDS can effectively detect the spatial heterogeneity of resistivity parameters in underground media, and is particularly suitable for identifying typical defects such as water-bearing fissures and seepage channels. GPR can acquire high-resolution dielectric parameter profiles of shallow strata and has excellent imaging capabilities for near-surface defects such as cracks in the dam crest and shallow voids. These complementary geophysical data reveal the structural characteristics of underground media from different physical property perspectives, providing crucial information support for the accurate identification of internal defects in earth-rock dams.

[0004] In recent years, the study of structural defects and malfunctions through the integration of geophysical information has received widespread attention from scholars at home and abroad. By verifying and supplementing information from multiple sources, the reliability of interpreting engineering defects and malfunctions has been effectively improved.

[0005] Traditional methods for detecting hidden dangers in earth-rock dams primarily rely on forward modeling to identify anomalous patterns in typical hidden dangers, and then use on-site measurements combined with forward modeling patterns to pinpoint the location and scale of anomaly zones. Essentially, this is a simple combination of two methods, depending on the visual comparison between forward modeling patterns and subsequent images. It is highly dependent on human experience, and the consistency of interpretation results may be poor.

[0006] Therefore, there is an urgent need for a method for identifying internal defects in earth-rock dam structures based on the fusion and interpretation of multi-source geophysical data. Summary of the Invention

[0007] To address the aforementioned issues, this application proposes a method for identifying hidden dangers in earth-rock embankments by fusing and interpreting multi-source geophysical data. This method aims to overcome the weaknesses in interpretation, low accuracy, and poor identification capabilities of traditional geophysical methods for identifying safety hazards in earth-rock embankments. It utilizes a high-density electrical resistivity tomography (EDT) instrument and a ground-penetrating radar (GPR) instrument to acquire multi-source underground geophysical information for earth-rock embankment projects and performs conventional geophysical inversion. Through data preprocessing, spatial registration, and information overlay of the inversion results, a defect anomaly response map fused from the multi-source geophysical data is output to visually represent the degree and distribution of defects. This achieves synergistic enhancement of the two types of geophysical information, effectively improving the interpretation and identification capabilities of internal defects in earth-rock embankment structures.

[0008] To achieve the above objectives, this invention proposes a method for identifying potential hazards in earth-rock embankments based on the fusion and interpretation of multi-source geophysical data, comprising the following steps: S1. (Acquiring multi-source geophysical data) The physical parameter signals of the internal medium of the earth-rock dam structure are collected by high-density electrical resistivity and ground penetrating radar methods. The interpretation results of the resistivity profile distribution data of the internal medium of the dam and the dielectric parameter profile distribution data of the shallow strata are obtained respectively. S2, (Kirchhoff migration and Hilbert transform processing of GPR data) Kirchhoff migration theory is used to perform migration and repositioning processing on the diffracted wave field, and Hilbert transform theory is combined to extract the instantaneous amplitude of ground penetrating radar electromagnetic waves. Due to factors such as electromagnetic wave diffraction and medium inhomogeneity, raw ground-penetrating radar (GPR) data suffers from signal ambiguity and difficulties in defect identification and location. To address these issues, this invention, based on signal denoising and enhancement methods such as filtering and correction, utilizes the Kirchhoff migration method to reposition the diffracted wave field, thereby accurately acquiring defect feature distribution information from the radar data profile. Furthermore, to achieve effective fusion of GPR signals and high-density resistivity information, Hilbert transform is used to extract the instantaneous amplitude of the GPR electromagnetic waves and superimpose it with the resistivity values.

[0009] S3. (Characterizing the abnormal information of hidden dangers and defects inside earth-rock embankments) Based on the prior knowledge of the soil medium of earth-rock embankments, the abnormal characteristic response mechanism of typical hidden dangers and defects in earth-rock embankments in high-density electrical resistivity tomography and ground penetrating radar is analyzed. Through normalization processing, different attribute values ​​are converted to a unified numerical range, thereby characterizing the abnormal information of hidden dangers and defects inside earth-rock embankments and obtaining the normalized characterization of defect abnormal information. High-density electrical resistivity tomography (EDS) and ground-penetrating radar (GPR) detection results show significant differences in physical property responses. The former primarily characterizes the spatial distribution of potential defects through anomalies in the resistivity of the medium, while the latter identifies target boundaries based on anomalous reflection characteristics caused by differences in the dielectric constants of different media. This invention, based on prior knowledge of the geological media of earth-rock embankments, analyzes the anomalous response mechanisms of typical potential defects in earth-rock embankments using EDS and GPR. Through normalization, different attribute values ​​are converted to a unified numerical range, eliminating the inherent differences in physical meaning and dimensions between the two methods, thereby achieving the characterization of anomalous information about potential defects within earth-rock embankments. S4. Spatial registration and fusion of the normalized representation of defect and anomaly information in S3 based on Kriging interpolation; Since ground-penetrating radar (GPR) and high-density electrical resistivity (EDS) data are heterogeneous sources, and the EDS resistivity inversion cloud map exhibits an inverted trapezoidal distribution, resulting in spatial scale heterogeneity, this invention employs Kriging interpolation to interpolate the normalized heterogeneous geophysical data. By utilizing the spatial correlation between known spatial point response characteristic values, unbiased estimation of the response characteristics of unknown spatial points is performed. Based on filling the blank areas in the EDS data, a regular grid of the target area is established and sampled to a uniform size to achieve spatial alignment of geophysical data from different sources. Through the fusion of electromagnetic heterogeneous feature information at the same node locations, the synergistic enhancement of the two geophysical information sources can be achieved, effectively improving the interpretation and identification of internal defects in earth-rock dam structures. S5. Based on S2, S3 and S4, obtain the fusion data of the electromagnetic heterogeneous source characteristics of the underground space of the earth-rock dam, normalize it to [0,1], and generate a feature response map of the fused defect anomaly information, so as to accurately identify the range and location of internal defects in the earth-rock dam structure.

[0010] Preferably, the acquisition of multi-source geophysical data in S1 is a fundamental step supporting the research. Among them, high-density electrical resistivity tomography can effectively detect the spatial heterogeneity of resistivity parameters of underground media, and is particularly suitable for identifying typical defects such as water-bearing fissures and seepage channels. Ground penetrating radar can acquire high-resolution dielectric parameter profiles of shallow strata and has excellent imaging capabilities for near-surface defects such as cracks in levee crests and shallow voids.

[0011] Preferably, the specific content of S2 is as follows: Based on Kirchhoff migration theory, the diffracted wave field is migrated and realigned to reconstruct the spatial position of the target anomaly's reflection interface, thus obtaining the underground target point. p Two-dimensional offset wave field values; Based on Hilbert transform theory, the instantaneous amplitude of ground-penetrating radar electromagnetic waves is extracted to characterize the intensity of signal energy, while the uneven change of energy characterizes the differences in underground media, thereby determining the severity and distribution characteristics of underground hidden dangers.

[0012] The raw time-domain signal received by the radar antenna of the ground-penetrating radar impulse response of the transformation Perform Hilbert transform convolution operations to construct complex signals and extract instantaneous amplitudes; The instantaneous amplitude of the electromagnetic wave of the ground-penetrating radar is used to characterize the intensity of the signal energy, while the uneven change of energy intensity characterizes the differences in the underground medium, thereby determining the severity and distribution characteristics of underground hidden dangers.

[0013] Preferred, underground target point p The expression for the two-dimensional offset wave field value is: ; In the formula: The electric field component is related to the spatial position. and time The relevant functions, For surface observation points To the underground target point p distance, The speed of electromagnetic wave propagation. For electromagnetic wave propagation time, This is a delay term, reflecting the electromagnetic wave's trajectory from the underground target point. p The time delay of the reflection to the receiving point on the ground. x Horizontal spatial coordinates z These are depth space coordinates.

[0014] Preferably, the expression for the Hilbert transform convolution operation is: ; In the formula: The time-domain kernel function of the Hilbert transform characterizes the time-domain impulse response. For the current moment, For the past moment, The original time-domain signal, These are the orthogonal components obtained through the Hilbert transform; Among them, with As the real part As a virtual part The imaginary unit is used to construct complex signals. ; Then extract the instantaneous amplitude. .

[0015] Preferably, the specific content of S3 is as follows: Identify abnormal resistivity conditions, including high resistivity abnormalities and low resistivity abnormalities; Anomalies in resistivity are identified, and the normalization process for high-density resistivity is determined based on these anomalies to achieve normalized characterization. These anomalies include high-resistivity anomalies and low-resistivity anomalies. The specific steps for identifying abnormal resistivity conditions include: Based on the resistivity characteristic parameters of typical soil and rock media in earth-rock dams, and combined with the overall background resistivity distribution of the profile, thresholds for high and low resistivity are set. When the local resistivity value is greater than the high resistivity threshold, it is judged as a high resistivity anomaly, and when the local resistivity value is less than the low resistivity threshold, it is judged as a low resistivity anomaly. To satisfy the fusion of heterogeneous information from ground-penetrating radar electromagnetic waves and high-density electrical resistivity, the instantaneous amplitude value of the ground-penetrating radar electromagnetic waves is adopted. Normalization is performed to achieve normalized representation. The larger the normalized value, the stronger the reflection and the lower the possibility of defects. Where, in the formula The normalized amplitude value at point i. Let be the instantaneous amplitude value at the i-th point. and These represent the maximum and minimum instantaneous amplitudes of a single survey line after Kirchhoff migration and Hilbert transformation, respectively.

[0016] Preferably, the specific content of determining the form of normalization processing based on abnormal situations is as follows: When the defect target is a high-resistivity anomaly, the following is adopted: Perform normalization processing; When the defect target is a low-resistance anomaly, the following is adopted: Perform normalization processing; In the formula: For the normalized first Resistivity values ​​at each point For the first Resistivity values ​​at each point and These represent the maximum and minimum resistivity values ​​for detecting potential hazards in earth-rock embankments.

[0017] Preferably, the specific content of S4 includes: S401. Kriging interpolation is used to interpolate the normalized representation of defect anomaly information, and the spatial correlation between known spatial point response characteristic values ​​is used to make unbiased estimation of the response characteristics of unknown spatial points. S402. Establish a regular grid for the target area and sample it to a uniform size. Superimpose and fuse the electromagnetic heterogeneous feature information at the same node location. Preferably, the kriging interpolation matrix in S401 is represented as follows: In the formula: Here, represents the Kriging weighting coefficient, and n represents the number of measured points within the detection area. For the variable Z in spatial position and The value of the variogram at that location, It is a Lagrange multiplier.

[0018] Preferably, in step S402, the target area is resampled to obtain the electromagnetic heterogeneous feature information at the same node location. Given a second-order stationary random function, its position in... common Sampling is performed at each spatial point, then the point The estimated value at the location is: ; The fused characteristic response value of the superposition of electromagnetic properties is: In the formula: This represents the resistivity response value at the unknown point obtained through interpolation. This represents the amplitude response value at the unknown point obtained through interpolation.

[0019] Preferably, step S5, the identification and location of internal defects in the earth-rock dam structure, specifically includes: According to steps S2, S3 and S4, the fusion data of electromagnetic heterogeneous source feature information of the underground space of the earth-rock dam is obtained, normalized to [0, 1] and a feature response map of fused defect anomaly information is generated, thereby realizing the synergistic enhancement of the two geophysical information and effectively improving the ability to interpret and identify the defects inside the earth-rock dam structure.

[0020] In summary, the method for identifying potential hazards in earth-rock dams based on the fusion and interpretation of multi-source geophysical data of the present invention has the following advantages compared with traditional technologies: This invention first utilizes a high-density electrical resistivity tomography (EDT) instrument and a ground-penetrating radar (GPR) instrument to acquire multi-source underground geophysical information for earth-rock embankment projects and performs conventional geophysical inversion. By preprocessing the inversion results, addressing the issue of unclear defect characteristics caused by diffraction wave scattering in GPR data, Kirchhoff migration imaging is used to realign the diffracted waves to their true locations, and Hilbert transform is combined to extract instantaneous attributes to obtain the inherent defect information distribution. Subsequently, the anomaly response mechanism of typical hidden defects in earth-rock embankments in EDT and GPR is analyzed, and the anomaly information is characterized. Then, a regularized grid is constructed using Kriging spatial interpolation to enhance the spatial continuity of the data. Simultaneously, spatial registration of ERT-GPR data is achieved through coordinate transformation and resolution matching. Under a unified spatial reference, the registered heterogeneous geophysical feature information is fused to generate a feature response map of fused defect anomaly information, thereby achieving synergistic enhancement of the two geophysical information sources and effectively improving the interpretation and identification of internal defects in earth-rock embankment structures. Compared with traditional single geophysical exploration methods, this method significantly suppresses the limitations and multiple solutions of single geophysical exploration methods, improves the accuracy of defect location and interpretation consistency, and can effectively solve the problems of misidentification and omission in traditional methods, enabling high-precision interpretation of internal defect and hidden danger information of earth-rock dams.

[0021] The technical method of the present invention will be further described in detail below with reference to the accompanying drawings and embodiments. Attached Figure Description

[0022] Figure 1 This is a schematic diagram of the overall process of the present invention; Figure 2 This is a flowchart of the method for identifying internal defects in earth-rock dam structures in this invention; Figure 3 This is a schematic diagram of spatial registration and fusion of ERT-GPR data for earth-rock embankments in this invention. Detailed Implementation

[0023] The technical method of the present invention will be further described below with reference to the accompanying drawings and embodiments. It should be noted that, unless otherwise specifically stated, the relative arrangement, numerical expressions, and values ​​of the components and steps described in these embodiments do not limit the scope of this application.

[0024] The following description of at least one exemplary embodiment is merely illustrative and is in no way intended to limit the scope of this application and its application or use.

[0025] Techniques, systems, and equipment known to those skilled in the art may not be discussed in detail, but where appropriate, they should be considered part of the instruction manual.

[0026] In all the examples shown and discussed herein, any specific values ​​should be interpreted as merely exemplary and not as limitations. Therefore, other examples of exemplary embodiments may have different values.

[0027] Unless otherwise defined, the technical or scientific terms used in this invention shall have the ordinary meaning as understood by one of ordinary skill in the art to which this invention pertains.

[0028] Example 1 like Figure 1 and Figure 2 As shown, the present invention includes the following steps: S1. Obtain multi-source geophysical data: The physical parameter signals of the internal medium of the earth-rock dam structure were collected by high-density electrical resistivity tomography (EDS) and ground-penetrating radar (GPR). The data were then processed using conventional methods to obtain geophysical data interpretation results of the dam's internal structural anomalies. The geophysical data interpretation results include high-density EDS interpretation results and GPR interpretation results.

[0029] Kirchhoff offset and Hilbert transform processing of S2 and GPR data: The Kirchhoff migration method is used to reorient the diffracted wave field, thereby accurately obtaining the defect feature distribution information of the radar data profile. Specifically, based on Kirchhoff migration theory, the spatial location of the target anomalous body's reflective interface and the underground target points are reconstructed in reverse. p The two-dimensional offset wave field value is: ; In the formula: The electric field component is related to the spatial position. and time The relevant functions, For surface observation points To the underground target point p distance, The speed of electromagnetic wave propagation. For electromagnetic wave propagation time, This is a delay term, reflecting the electromagnetic wave's trajectory from the underground target point. p The time delay of the reflection to the receiving point on the ground. x Horizontal spatial coordinates z For depth space coordinates; The instantaneous amplitude of ground-penetrating radar electromagnetic waves is extracted using Hilbert transform. Specifically, based on Hilbert transform theory, the instantaneous amplitude of the ground-penetrating radar electromagnetic waves is extracted to characterize the intensity of the signal energy. This is done by analyzing the original time-domain signal received by the radar antenna. impulse response of the transformation The specific formula for performing Hilbert transform convolution is as follows: ; In the formula: The time-domain kernel function of the Hilbert transform characterizes the time-domain impulse response. For the current moment, For the past moment, The original time-domain signal, These are the orthogonal components obtained through the Hilbert transform; where, with As the real part As a virtual part The imaginary unit is used to construct complex signals. And extract the instantaneous amplitude as In order to obtain the distribution of the inherent defect information.

[0030] S3. Characterize the abnormal information of hidden defects and hazard inside earth-rock dams: Based on prior knowledge of the geological media of earth-rock embankments, this paper analyzes the anomaly response mechanism of typical hidden defects in earth-rock embankments in high-density electrical resistivity tomography (EDS) and ground-penetrating radar (GPR). Through normalization, different attribute values ​​are converted to a unified numerical range, eliminating the inherent differences in physical meaning and dimensions between the two methods. Specifically, when the defect target is a high-resistivity anomaly, the following method is used: Normalization is performed; when the defect target is a low-resistivity anomaly, the following is adopted: Normalization is performed; where: For the normalized first Resistivity values ​​at each point For the first Resistivity values ​​at each point and These represent the maximum and minimum resistivity values ​​for detecting potential hazards in earth-rock embankments; the instantaneous amplitude value of the electromagnetic wave from the ground-penetrating radar also needs to be adopted. After normalization, the larger the normalized value, the stronger the reflection and the higher the probability of defects. In the formula... The normalized amplitude value at point i. Let be the instantaneous amplitude value at the i-th point. and These represent the maximum and minimum instantaneous amplitudes of a single survey line after Kirchhoff migration and Hilbert transformation, respectively.

[0031] S4. Spatial registration and fusion of ERT-GPR data for earth-rock embankments based on Kriging interpolation: Kriging interpolation was used to interpolate normalized heterogeneous geophysical data, such as... Figure 3 As shown, the specific expression is: ; In the formula: Here, represents the Kriging weighting coefficient, and n represents the number of measured points within the detection area. For the variable Z in spatial position and The value of the variogram at that location, Let the Lagrange multiplier be used; the target region is resampled to obtain the electromagnetic heterogeneous source feature information at the same node location, specifically: let... Given a second-order stationary random function, its position in... common Sampling is performed at each spatial point, then the point The estimated value at the location is: The fused characteristic response value of the superposition of electro-magnetic properties is: In the formula: This represents the resistivity response value at the unknown point obtained through interpolation. This represents the amplitude response value at the unknown point obtained through interpolation.

[0032] S5. Identification and location of internal defects in earth-rock dam structures: According to steps S2, S3 and S4, the fusion data of the electromagnetic heterogeneous source characteristics of the underground space of the earth-rock dam is obtained, normalized to [0, 1] and a feature response map of the fused defect anomaly information is generated, so as to accurately identify the range and location of internal defects of the earth-rock dam structure.

[0033] Finally, it should be noted that the above embodiments are only used to illustrate the technical methods of the present invention and not to limit them. Although the present invention has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions can still be made to the technical methods of the present invention, and these modifications or equivalent substitutions cannot cause the modified technical methods to deviate from the spirit and scope of the technical methods of the present invention.

Claims

1. A method for identifying potential hazards in earth-rock embankments based on the fusion and interpretation of multi-source geophysical data, characterized in that, Includes the following steps: S1. Collect physical parameter signals of the internal medium of the earth-rock dam structure by high-density electrical resistivity and ground-penetrating radar methods, and obtain the interpretation results of resistivity profile distribution data of the internal medium of the dam and dielectric parameter profile distribution data of the shallow strata respectively. S2. The diffracted wave field is offset and repositioned using Kirchhoff's migration theory, and the instantaneous amplitude of the ground-penetrating radar electromagnetic wave is extracted by combining Hilbert's transformation theory. S3. Based on prior knowledge of the soil medium of earth-rock embankments, the abnormal characteristic response mechanism of typical hidden defects in earth-rock embankments in high-density electrical resistivity tomography and ground-penetrating radar is analyzed. By normalization processing, different attribute values ​​are converted to a unified numerical range, thereby characterizing the abnormal information of hidden defects inside earth-rock embankments and obtaining the normalized characterization of defect abnormal information. S4. Spatial registration and fusion of the normalized representation of defect and anomaly information in S3 based on Kriging interpolation; S5. Based on steps S2, S3 and S4, obtain the fusion data of electromagnetic heterogeneous source characteristics of the underground space of the earth-rock dam, normalize it to [0,1], and generate a feature response map of fused defect anomaly information.

2. The method for identifying hidden dangers in earth-rock embankments based on the fusion and interpretation of multi-source geophysical data as described in claim 1, characterized in that, The specific content of S2 is as follows: Based on Kirchhoff migration theory, the diffracted wave field is migrated and realigned to reconstruct the spatial position of the target anomaly's reflection interface, thus obtaining the underground target point. p Two-dimensional offset wave field values; The raw time-domain signal received by the radar antenna of the ground-penetrating radar impulse response of the transformation Perform Hilbert transform convolution operations to construct complex signals and extract instantaneous amplitudes; The instantaneous amplitude of the electromagnetic wave of the ground-penetrating radar is used to characterize the intensity of the signal energy, while the uneven change of energy intensity characterizes the differences in the underground medium, thereby determining the severity and distribution characteristics of underground hidden dangers.

3. The method for identifying hidden dangers in earth-rock embankments based on the fusion and interpretation of multi-source geophysical data as described in claim 2, characterized in that, underground target point p The expression for the two-dimensional offset wave field value is: ； In the formula: The electric field component is related to the spatial position. and time The relevant functions, For surface observation points To the underground target point p distance, The speed of electromagnetic wave propagation. For electromagnetic wave propagation time, This is a delay term, reflecting the electromagnetic wave's trajectory from the underground target point. p The time delay of the reflection to the receiving point on the ground. x Horizontal spatial coordinates z These are depth space coordinates.

4. The method for identifying hidden dangers in earth-rock embankments based on the fusion and interpretation of multi-source geophysical data as described in claim 2, characterized in that, The expression for the Hilbert transform convolution operation is: ； In the formula: The time-domain kernel function of the Hilbert transform characterizes the time-domain impulse response. For the current moment, For the past moment, The original time-domain signal, These are the orthogonal components obtained through the Hilbert transform; Among them, with As the real part, As a virtual part The imaginary unit is used to construct complex signals. ; Then extract the instantaneous amplitude. .

5. The method for identifying hidden dangers in earth-rock embankments based on the fusion and interpretation of multi-source geophysical data as described in claim 1, characterized in that, The specific content of S3 is as follows: Identify abnormal resistivity conditions, including high resistivity abnormalities and low resistivity abnormalities; Anomalies in resistivity are identified, and the normalization process for high-density resistivity is determined based on these anomalies to achieve normalized characterization. These anomalies include high-resistivity anomalies and low-resistivity anomalies. The specific steps for identifying abnormal resistivity conditions include: Based on the resistivity characteristic parameters of typical soil and rock media in earth-rock dams, and combined with the overall background resistivity distribution of the profile, thresholds for high and low resistivity are set. When the local resistivity value is greater than the high resistivity threshold, it is judged as a high resistivity anomaly, and when the local resistivity value is less than the low resistivity threshold, it is judged as a low resistivity anomaly. The instantaneous amplitude value of ground-penetrating radar electromagnetic waves is adopted Normalization is performed to achieve normalized representation. The larger the normalized value, the stronger the reflection and the lower the possibility of defects. Where, in the formula The normalized amplitude value at point i. Let be the instantaneous amplitude value at the i-th point. and These represent the maximum and minimum instantaneous amplitudes of a single survey line after Kirchhoff migration and Hilbert transformation, respectively.

6. The method for identifying hidden dangers in earth-rock embankments based on the fusion and interpretation of multi-source geophysical data as described in claim 5, characterized in that, The specific details of determining the form of normalization processing based on abnormal situations are as follows: When the defect target is a high-resistivity anomaly, the following is adopted: Perform normalization processing; When the defect target is a low-resistance anomaly, the following is adopted: Perform normalization processing; In the formula: For the normalized first Resistivity values ​​at each point For the first Resistivity values ​​at each point and These represent the maximum and minimum resistivity values ​​for detecting potential hazards in earth-rock embankments.

7. The method for identifying hidden dangers in earth-rock embankments based on the fusion and interpretation of multi-source geophysical data as described in claim 1, characterized in that, The specific content of S4 includes: S401. Kriging interpolation is used to interpolate the normalized representation of defect anomaly information, and the spatial correlation between known spatial point response characteristic values ​​is used to make unbiased estimation of the response characteristics of unknown spatial points. S402. Establish a regular grid for the target area and sample it to a uniform size. Overlay and fuse the electromagnetic heterogeneous feature information at the same node location.

8. The method for identifying hidden dangers in earth-rock embankments based on the fusion and interpretation of multi-source geophysical data as described in claim 7, characterized in that, The Kriging interpolation matrix in S401 is represented as follows: In the formula: denoted by Kriging weights, and n represents the number of measured points within the detection area. For the variable Z in spatial position and The value of the variogram at that location, It is a Lagrange multiplier.

9. The method for identifying hidden dangers in earth-rock embankments based on the fusion and interpretation of multi-source geophysical data as described in claim 8, characterized in that, In S402, the target area is resampled to obtain the electromagnetic heterogeneous feature information at the same node location. Given a second-order stationary random function, its position in... common Sampling is performed at each spatial point, then the point The estimated value at the location is: ; The fused characteristic response value of the superposition of electromagnetic properties is: In the formula: This represents the resistivity response value at the unknown point obtained through interpolation. This represents the amplitude response value at the unknown point obtained through interpolation.

10. The method for identifying hidden dangers in earth-rock embankments based on the fusion and interpretation of multi-source geophysical data as described in claim 9, characterized in that, Step S5, the identification and location of internal defects in the earth-rock dam structure, specifically involves: According to steps S2, S3 and S4, the fusion data of electromagnetic heterogeneous source feature information of the underground space of the earth-rock dam is obtained, normalized to [0, 1] and a feature response map of fused defect anomaly information is generated, thereby realizing the synergistic enhancement of the two geophysical information and effectively improving the ability to interpret and identify the defects inside the earth-rock dam structure.

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