An anti-interference acquisition and analysis method for electrical exploration signals

Abstract

This invention discloses an anti-interference acquisition and analysis method for electrical exploration signals, relating to the field of exploration signal processing. The method includes: deploying an electrode array according to the stratigraphic strike of the exploration area; calibrating the timing coupling reference of the array nodes and initiating in-situ electrical signal acquisition; and performing continuous frame synchronous interception of the acquired signals according to the calibrated timing reference to generate a fixed-length in-situ signal frame sequence. By combining the deployment of electrodes with geological features and synchronous acquisition of electrical signals, this invention can adapt to the electrical conduction characteristics of different strata, reduce the impact of on-site electromagnetic interference on the acquired data, accurately calibrate signal timing and amplitude, effectively distinguish effective stratigraphic signals from environmental noise, and unify data quantization standards to reduce measurement errors.

Description

Technical Field

[0001] This invention relates to the field of exploration signal processing technology, specifically to a method for anti-interference acquisition and analysis of electrical exploration signals. Background Technology

[0002] Electrical resistivity tomography (ERT) is a geophysical exploration method that detects underground geological bodies by observing the spatiotemporal distribution patterns of artificial or natural electric fields based on differences in the conductivity of underground media. It is widely used in fields such as engineering geology, hydrogeology, and mineral resource exploration. Its core is to collect and analyze the electrical signals generated during the exploration process, and to extract key parameters such as resistivity and polarizability from the signals to invert the distribution characteristics of the underground media.

[0003] Patent application No. 201810623258.5 discloses an anti-interference method and system for multi-channel receivers. This application aims to address the problem that "existing electrical exploration methods and instruments typically employ multi-channel receivers, but the accuracy of these methods remains low due to significant interference from the external environment, making it difficult to extract useful signals. External interference mainly includes random interference from the environment, power frequency interference from electric lines, and spike interference from electrical sparks. Existing anti-interference methods have significant shortcomings; excessive interference leads to low accuracy in electrical exploration."

[0004] However, existing technologies use traditional, single anti-interference methods, and the acquisition and analysis stages are disconnected, making it impossible to suppress complex interference and accurately compensate signals in real time.

[0005] To address this, we propose a method for interference-resistant acquisition and analysis of electrical exploration signals. Summary of the Invention

[0006] In view of the above-mentioned shortcomings of the existing technology, the present invention provides a method for anti-interference acquisition and analysis of electrical exploration signals, which can effectively solve the problems of the existing technology.

[0007] To achieve the above objectives, the present invention is implemented through the following technical solutions; This invention discloses a method for anti-interference acquisition and analysis of electrical exploration signals, comprising: Electrode arrays were deployed according to the stratigraphic strike of the exploration area. The timing coupling reference of the array nodes was calibrated, and in-situ electrical signal acquisition was initiated. According to the calibrated timing reference, continuous frame synchronous interception was performed on the acquired signals to generate a fixed-length in-situ signal frame sequence. Electrical feature bits were extracted directionally along the timing axis of the in-situ signal frame sequence to complete the directional partitioning and aggregation of signal data within the frame. In-situ normalization processing was performed on the aggregated feature bit data to unify the quantization dimension of the data within the frame. Based on the normalized feature bit data, in-situ coupling analytical modeling of stratigraphic electrical parameters was performed synchronously. The in-situ coupling analytical modeling data was aligned frame by frame with the corresponding acquired in-situ signal frames to complete the timing binding of the acquired and analyzed data.

[0008] Furthermore, when deploying the electrode array according to the stratigraphic strike of the exploration area, the following should be followed: Azimuth data of the strike of strata in the exploration area are collected. Based on the distribution direction of the anisotropic distribution of the electrical conductivity of the strata, a non-uniform gridded electrode array is deployed. The arrangement axis of the array nodes is orthogonal to the dip axis of the strata. The spacing between adjacent array nodes is adjusted according to the electrical conductivity of the strata. The spatial three-dimensional coordinates of each array node are recorded. A one-to-one correspondence between the three-dimensional coordinates of the array nodes and the electrode excitation channel and signal acquisition channel is established, and a spatial topology mapping matrix of the electrode array is generated.

[0009] Furthermore, in the stage of calibrating the timing coupling reference of the array nodes, the electrode array nodes corresponding to the electrical center of the strata in the survey area are used as the global synchronization reference source. Based on the electromagnetic propagation characteristics of the strata medium, the acquisition trigger delay compensation of each array node is calculated. The timing reference value of each array node is determined according to the delay compensation to complete the global timing synchronization calibration. ; In the formula: This is the timing reference value for the calibration of the nth array node; The initial synchronization timing values ​​for the reference source array nodes; is the spatial straight-line distance between the nth array node and the reference source array node; The speed of electromagnetic wave propagation in a vacuum; The relative permittivity of the strata in the survey area; The relative magnetic permeability of the formation; The electromagnetic attenuation coefficient of the stratum corresponding to the nth array node is... It is a natural constant; in, This represents the amount of time delay compensation.

[0010] Furthermore, when performing continuous frame synchronous interception on the acquired signal, the calibrated global timing coupling reference is used as the trigger origin. Based on the preset frame period, non-overlapping, phase-locked interception is performed on the in-situ electrical signal. During the interception process, the dual-dimensional deviation of the frame start phase and amplitude is checked in real time. When the deviation of either dimension exceeds the preset threshold, adaptive frame synchronization dynamic correction is triggered. Based on the correction amount, the frame start timing is re-locked and the amplitude is normalized and adjusted to generate an in-situ signal frame sequence with consistent phase and amplitude.

[0011] Furthermore, when extracting electrical feature bits along the time-series axis of the in-situ signal frame sequence, the entire time-series range of a single frame signal is traversed. The linkage characteristics of the potential time-series gradient and the formation contact impedance are fused to construct a nonlinear feature discrimination function, and time-series points that satisfy the formation electrical abrupt change constraint are selected as electrical feature bits. ; In the formula: The comprehensive discrimination value of the electrical characteristics of the k-th time-series point; This represents the signal potential value at that point. This is the formation contact impedance value of the electrode corresponding to this point; It is a time-sequential differential unit; Preset constraint coefficients for feature selection; The standard deviation of the background potential fluctuation of a single frame signal; The standard deviation of background fluctuation in contact impedance for a single frame; when When the time point is determined to be a valid electrical characteristic bit, it is considered to be a valid electrical characteristic bit.

[0012] Furthermore, in the directional partitioning and aggregation stage of intra-frame signal data, based on the temporal distribution of effective electrical feature bits and the amplitude of comprehensive discrimination values, the intra-frame signal data is divided into a formation response feature area and an environmental interference noise area. The data is then partitioned and aggregated, and a three-dimensional mapping relationship between feature bits, partitioned data and temporal points is established. Redundant and invalid data that exceeds the background fluctuation constraints in the noise area are adaptively removed.

[0013] Furthermore, in the in-situ normalization stage of the collected feature bit data, using the in-situ stratigraphic reference electrical parameters of the survey area as the constraint benchmark, and integrating the dual-dimensional constraints of feature bit amplitude and spatial topological location, nonlinear mapping normalization processing is performed: ; In the formula: This is the normalized quantized value of the potential of the nth characteristic bit. These are the original characteristic potential values ​​before normalization; This serves as the in-situ reference potential for the strata in the survey area. This represents the saturation potential of the formation's electrical response. Preset adjustment coefficients for nonlinear mapping; The spatial radial distance of the array node corresponding to the nth feature bit; The average radial distance between array nodes; It is the hyperbolic tangent function.

[0014] Furthermore, the aforementioned ∈[0.5, 2], when the electrical heterogeneity of the stratum increases or the spatial arrangement deviation of the electrode array increases. The value increases accordingly when the stratum electrical properties are uniform and the electrode array is laid out with high precision. The value decreases accordingly.

[0015] Furthermore, in the in-situ coupled analytical modeling stage of formation electrical parameters, normalized eigenvalue quantization data are used as input. Multi-parameter linkage constraints of formation resistivity, dielectric constant, and polarizability are coupled, and combined with the spatial topology mapping matrix of the electrode array, a three-dimensional coupled analytical model of global formation electrical parameters is constructed. The model solver outputs a formation electrical parameter distribution tensor that corresponds one-to-one with the spatial location of the survey area. ; In the formula: Spatial coordinates The distribution tensor of formation electrical parameters at the location; This is the spatial topology mapping matrix of the electrode array; Spatial coordinates The resistivity of the formation at that location; Let be the relative permittivity of the formation at spatial coordinates (x, y, z); Spatial coordinates The formation polarization at that location; Spatial coordinates The spatial gradient vector of the electromagnetic attenuation coefficient at that location; This represents the temporal rate of change of formation polarizability.

[0016] Furthermore, the timing-based binding operation of the data acquisition and parsing follows the following rules: Using the global time series number of the in-situ signal frame as the unique association identifier, the tensor data of formation electrical parameter distribution is precisely aligned frame by frame with the corresponding signal frame in both spatial and temporal dimensions. The aligned data is then encrypted end-to-end using the AES-256 symmetric encryption algorithm to generate an integrated time series association dataset, which is written to the local encrypted storage medium. The temporal continuity of the dataset is verified based on the preset time series sampling interval, and the spatial matching degree of the dataset is verified based on the electrode array spatial topology mapping matrix. When the time series interval between two consecutive frames of data exceeds the sampling interval threshold or the electrical parameter data corresponding to the spatial coordinates is null, it is determined that the data is missing. When the data is missing, a directional in-situ supplementary sampling command is triggered. The directional in-situ data acquisition instruction includes the timing number, spatial coordinate array node, excitation current parameter, and acquisition duration parameter corresponding to the missing data, which controls the corresponding electrode array node to perform in-situ data acquisition and backfill the missing data.

[0017] Compared with the known prior art, the technical solution provided by this invention has the following beneficial effects: This invention utilizes an electrode array layout adapted to the formation strike and a time-synchronized acquisition method to align with the anisotropic characteristics of formation electrical conduction, reducing spatial deviations in signal acquisition. It monitors and adjusts acquisition parameters in real time, enhancing the anti-interference capability and stability of on-site signal acquisition. It precisely compensates for signal propagation delays at array nodes, achieving time-series uniformity across all acquisition array nodes. Furthermore, it performs frame-synchronized interception and dynamic correction on the acquired signals, ensuring consistency in signal frame phase and amplitude. It accurately filters formation electrical characteristics and processes data in zones, effectively filtering environmental interference noise. Normalization eliminates data deviations caused by formation differences and layout errors. Coupled with multiple formation parameters, it completes electrical analysis, achieving precise time-series binding of acquired and analyzed data. This ensures the stability, continuity, and accuracy of exploration data acquisition and analysis. Attached Figure Description

[0018] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the accompanying drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are merely some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without any creative effort.

[0019] Figure 1 This is a flowchart illustrating a method for anti-interference acquisition and analysis of electrical exploration signals. Detailed Implementation

[0020] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of the present invention. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without creative effort are within the scope of protection of the present invention.

[0021] The present invention will be further described below with reference to embodiments.

[0022] Example: This embodiment presents a method for anti-interference acquisition and analysis of electrical exploration signals, such as... Figure 1 As shown, it includes: Electrode arrays were deployed according to the stratigraphic strike of the exploration area, the timing coupling reference of the array nodes was calibrated, and in-situ electrical signal acquisition was initiated. When deploying the electrode array according to the stratigraphic strike of the exploration area, the following should be followed: Azimuth data of the strike of strata in the exploration area are collected. Based on the distribution direction of the anisotropic distribution of the electrical conductivity of the strata, a non-uniform gridded electrode array is deployed. The arrangement axis of the array nodes is orthogonal to the dip axis of the strata. The spacing between adjacent array nodes is adjusted according to the electrical conductivity of the strata. The spatial three-dimensional coordinates of each array node are recorded. A one-to-one correspondence between the three-dimensional coordinates of the array nodes and the electrode excitation channel and signal acquisition channel is established, and the spatial topology mapping matrix of the electrode array is generated. The expression for adjusting the spacing between adjacent array nodes based on the formation's electrical conductivity is as follows: ; In the formula: The spacing between adjacent electrode array nodes in the m-th group; This represents the in-situ electrical conductivity velocity of the strata in the survey area. The reference angular frequency for the electrode excitation signal; Let be the electrical conductivity anisotropy coefficient of the stratum corresponding to the m-th array node; The above formula combines the in-situ electrical conduction velocity of the strata in the test area, the reference angular frequency of the electrode excitation signal, and the anisotropy coefficient of the strata electrical conduction to calculate the spacing of the electrode array nodes. The distance between the array nodes can be dynamically adjusted according to the actual conduction characteristics of the strata, so that the electrode arrangement is more in line with the electrical conduction law of the strata, effectively improving the adaptability and stability of in-situ signal acquisition. The value of follows the following rule: the electrical conductivity of the formation is measured along the dip direction and perpendicular to the dip direction, and the ratio of the electrical conductivity in the two directions is used as the electrical conductivity anisotropy coefficient. The more significant the anisotropy, the better. The larger the value; After in-situ electrical signal acquisition is initiated, the dynamic changes of contact impedance of electrode array nodes, signal-to-noise ratio and electromagnetic attenuation coefficient are monitored in real time across the entire domain. When any parameter exceeds the preset constraint range, the amplitude and phase parameters of electrode excitation current are adaptively adjusted to dynamically optimize the anti-interference performance of the acquisition link, so as to ensure the effectiveness and stability of in-situ electrical signal acquisition. In the calibration stage of array node timing coupling reference, the electrode array node corresponding to the electrical center of the strata in the survey area is used as the global synchronization reference source. Based on the electromagnetic propagation characteristics of the strata medium, the acquisition trigger delay compensation of each array node is calculated. The timing reference value of each array node is determined according to the delay compensation to complete the global timing synchronization calibration. ; In the formula: This is the timing reference value for the calibration of the nth array node; The initial synchronization timing values ​​for the reference source array nodes; is the spatial straight-line distance between the nth array node and the reference source array node; The speed of electromagnetic wave propagation in a vacuum; The relative permittivity of the strata in the survey area; The relative magnetic permeability of the formation; The electromagnetic attenuation coefficient of the stratum corresponding to the nth array node is... It is a natural constant; The above formula uses the formation electrical center electrode array node as the synchronization reference, integrates the array node spacing, electromagnetic wave propagation speed, formation dielectric constant, magnetic permeability and electromagnetic attenuation coefficient to calculate the timing reference value, accurately compensates for the acquisition trigger delay of each array node, realizes the synchronous calibration of the entire electrode array node, and solves the timing offset problem caused by the difference in formation medium propagation. in, Indicates the amount of delay compensation; According to the calibrated timing reference, the acquired signal is subjected to continuous frame synchronous interception to generate a fixed-length in-situ signal frame sequence; When performing continuous frame synchronous interception on the acquired signal, the calibrated global timing coupling reference is used as the trigger origin. Based on the preset frame period, the in-situ electrical signal is intercepted without overlap and with phase-locked loop. During the interception process, the two-dimensional deviation of the frame start phase and amplitude is checked in real time. When the deviation of either dimension exceeds the preset threshold, adaptive frame synchronization dynamic correction is triggered. Based on the correction amount, the frame start timing is re-locked and the amplitude is normalized and adjusted to generate an in-situ signal frame sequence with consistent phase and amplitude. Among them, the adaptive frame synchronization dynamic correction follows: ; In the formula: This is the adaptive synchronization correction amount for the frame start point; This is the frame start phase deviation value; To acquire the excitation angular frequency of the signal; The reference time interval for a single cycle of the excitation signal; This is the amplitude deviation value of the frame start signal; The reference amplitude of the excitation signal; The above formula combines phase deviation, excitation angular frequency, amplitude deviation and excitation signal single-cycle reference to calculate the synchronization correction amount, while taking into account the dynamic correction of phase and amplitude deviation in both dimensions, to ensure phase locking and amplitude uniformity when the signal frame is captured, and to avoid frame synchronization failure caused by external interference. Electrical feature bits are extracted directionally along the time axis of the in-situ signal frame sequence to complete the directional partitioning and collection of intra-frame signal data; When extracting electrical feature bits along the time-series axis of the in-situ signal frame sequence, the entire time-series range of a single frame signal is traversed. The linkage characteristics of the potential time-series gradient and the formation contact impedance are fused to construct a nonlinear feature discrimination function, and time-series points that satisfy the formation electrical abrupt change constraint are selected as electrical feature bits. ; In the formula: The comprehensive discrimination value of the electrical characteristics of the k-th time-series point; This represents the signal potential value at that point. This is the formation contact impedance value of the electrode corresponding to this point; It is a time-sequential differential unit; Preset constraint coefficients for feature selection; The standard deviation of the background potential fluctuation of a single frame signal; The standard deviation of background fluctuation in contact impedance for a single frame; The above formula integrates the potential time gradient and formation contact impedance change characteristics to construct a discriminant function. Combined with the background fluctuation standard deviation of signal potential and contact impedance and the constraint coefficient, it screens effective electrical feature sites, which can accurately identify the sites of sudden changes in formation electrical properties and suppress feature misjudgment caused by background noise. when When this time point is determined, it is identified as a valid electrical characteristic bit; in, That is, the time-series sampling differential interval of a single frame signal, the value of which is equal to the sampling period of signal acquisition, used to characterize the time increment between two adjacent time-series sampling points. The design is based on the requirements of background interference intensity and feature recognition accuracy in the survey area, specifically constrained by the dual conditions of effectively identifying abrupt changes in the electrical properties of the strata while suppressing misjudgments caused by background noise. The value of is related to the standard deviation of the background fluctuation of the stratigraphy in the survey area. , There is a positive correlation. In the directional partitioning and collection phase of intra-frame signal data, based on the temporal distribution of effective electrical characteristic bits and the amplitude of comprehensive discrimination value, the intra-frame signal data is divided into the stratum response characteristic area and the environmental interference noise area. The data is collected in partitions and a three-dimensional mapping relationship between characteristic bits, partition data and temporal points is established. Redundant and invalid data that exceed the background fluctuation constraints in the noise area are adaptively removed. Perform in-situ normalization on the aggregated feature bit data to unify the quantization dimension of intra-frame data; In the in-situ normalization stage of the collected feature bit data, the in-situ stratigraphic reference electrical parameters of the survey area are used as the constraint benchmark. The dual-dimensional constraints of feature bit amplitude and spatial topological location are integrated, and nonlinear mapping normalization is performed to eliminate the quantization error caused by differences in stratigraphic medium and array layout deviation. ; In the formula: This is the normalized quantized value of the potential of the nth characteristic bit. These are the original characteristic potential values ​​before normalization; This serves as the in-situ reference potential for the strata in the survey area. This represents the saturation potential of the formation's electrical response. Preset adjustment coefficients for nonlinear mapping; The spatial radial distance of the array node corresponding to the nth feature bit; The average radial distance between array nodes; It is the hyperbolic tangent function; This formula uses hyperbolic tangent nonlinear mapping, and combines formation reference potential, saturation potential, array node spatial radial distance and adjustment coefficient to complete the normalization of characteristic bit data. It can eliminate the quantization error caused by formation medium differences and electrode array layout deviation, so as to flexibly adapt to different formation heterogeneity and layout accuracy scenarios. ∈[0.5, 2], when the electrical heterogeneity of the stratum increases or the spatial arrangement deviation of the electrode array increases. The value increases accordingly when the stratum electrical properties are uniform and the electrode array is laid out with high precision. The value should decrease accordingly. calculate When the hyperbolic tangent function is used, it is: ; In the formula, , It is a natural constant; Based on normalized feature bit data, in-situ coupled analytical modeling of formation electrical parameters is performed synchronously. In the in-situ coupled analytical modeling stage of formation electrical parameters, normalized eigenvalue quantization data are used as input. Multi-parameter constraints of formation resistivity, dielectric constant, and polarizability are coupled, and combined with the spatial topology mapping matrix of the electrode array, a three-dimensional coupled analytical model of global formation electrical parameters is constructed. The model solver outputs a formation electrical parameter distribution tensor that corresponds one-to-one with the spatial location of the survey area. ; In the formula: Spatial coordinates The distribution tensor of formation electrical parameters at the location; This is the spatial topology mapping matrix of the electrode array; Spatial coordinates The resistivity of the formation at that location; Let be the relative permittivity of the formation at spatial coordinates (x, y, z); Spatial coordinates The formation polarization at that location; Spatial coordinates The spatial gradient vector of the electromagnetic attenuation coefficient at that location; This represents the temporal rate of change of formation polarizability; The above formula couples normalized feature data, the spatial topology matrix of the electrode array, and multiple parameters such as formation resistivity and dielectric constant to construct a three-dimensional coupled analytical model. It outputs an electrical parameter distribution tensor that accurately corresponds to the spatial location, realizing in-situ linkage analysis of formation electrical parameters, thereby improving the accuracy and spatial matching of parameter analysis. The in-situ coupled analytical modeling data is aligned frame by frame with the corresponding in-situ signal frames generated by the acquisition, thus completing the time-series binding of the acquired and analyzed data. The time-series binding operation for data acquisition and parsing follows the following rules: Using the global time series number of the in-situ signal frame as the unique association identifier, the tensor data of formation electrical parameter distribution is precisely aligned frame by frame with the corresponding signal frame in both spatial and temporal dimensions. The aligned data is then encrypted end-to-end using the AES-256 symmetric encryption algorithm to generate an integrated time series association dataset, which is written to the local encrypted storage medium. The temporal continuity of the dataset is verified based on the preset time series sampling interval, and the spatial matching degree of the dataset is verified based on the electrode array spatial topology mapping matrix. When the time series interval between two consecutive frames of data exceeds the sampling interval threshold or the electrical parameter data corresponding to the spatial coordinates is null, it is determined that the data is missing. When the data is missing, a directional in-situ supplementary sampling command is triggered. The directional in-situ data acquisition instruction includes the timing number, spatial coordinate array node, excitation current parameter, and acquisition duration parameter corresponding to the missing data, which controls the corresponding electrode array node to perform in-situ data acquisition and backfill the missing data.

[0023] The method described in the above embodiments, by combining the geological characteristics of the strata to deploy electrodes and simultaneously collect electrical signals, can adapt to the electrical conduction characteristics of different strata, reduce the impact of on-site electromagnetic interference on the collected data, accurately calibrate the signal timing and amplitude, effectively distinguish between effective strata signals and environmental noise, unify data quantification standards to reduce calculation errors, combine multiple parameters to complete the analysis of strata electrical data, achieve accurate correspondence between collected and analyzed data, encrypt and store data and verify data integrity, promptly supplement missing data, improve the stability of on-site data acquisition and the accuracy of analysis results in electrical exploration, and effectively ensure the efficient conduct of exploration operations.

[0024] It should be noted that: In the above embodiments, the method in specific implementation scenarios determines the feature selection preset constraint coefficient, nonlinear mapping preset adjustment coefficient, in-situ reference potential of the strata in the test area, saturation potential of the strata electrical response, and electromagnetic attenuation coefficient of the strata corresponding to the nth array node through in-situ measurement and hierarchical selection. Among them, ξ is selected hierarchically based on the measured results of the power frequency interference intensity and random noise amplitude in the test area. The stronger the background noise, the larger the value of ξ, and the value range is 0.3~1.2. β is linearly selected within the range of 0.5~2 based on the measured values ​​of strata electrical heterogeneity and electrode layout deviation. The stronger the strata heterogeneity and the greater the electrode spatial deviation, the larger the value of β. The value was determined by continuously collecting the in-situ electrode potential in the test area under no-excitation conditions for 30 minutes and taking the average value. The signal potential was obtained by gradually increasing the excitation current until it reached a saturation state where the signal potential no longer changed significantly. The propagation attenuation test method of electromagnetic waves in the formation medium is adopted. The amplitude attenuation ratio of the transmitted and received signals is calculated in real time to ensure that the values ​​of each parameter are based on field measurements and can be directly quantified and implemented.

[0025] The three-dimensional coupled analytical model of formation electrical parameters is realized by the finite element numerical solution method. The spatial topological mapping matrix of the electrode array is used as the constraint boundary. The normalized feature bit quantization data is used as the input vector. The spatial coordinates (x,y,z) are meshed. The initial iteration values ​​and convergence thresholds of resistivity, relative permittivity and polarizability are set. The model is solved by the Newton-Raphson iteration method. When the error of the electrical parameter distribution tensor between two adjacent iterations is less than 10^-6, it is determined to be converged, and a stable formation electrical parameter distribution tensor is output.

[0026] The phase and amplitude deviation thresholds, acquisition parameter constraint ranges, and data missing judgment thresholds for adaptive frame synchronization dynamic correction are all quantitatively set using on-site calibration. The frame start phase deviation threshold is set to ±5°, and the amplitude deviation threshold is set to ±3% of the reference amplitude. Exceeding these ranges triggers synchronization correction. The constraint ranges for electrode array node contact impedance and signal-to-noise ratio are calibrated according to the geological medium conditions of the survey area. The contact impedance constraint range is 10Ω~10kΩ, and the signal-to-noise ratio constraint range is not less than 20dB. The data missing judgment threshold is when the time interval between two consecutive frames exceeds 1.2 times the preset sampling interval or when the electrical parameter data corresponding to the spatial coordinates remains empty for more than one frame.

[0027] See the application examples of the method in the above embodiments: In a geological electrical exploration operation in a metal mine exploration area, the strata exhibit significant anisotropy in electrical conduction characteristics, and the presence of power frequency electromagnetic interference at the site can easily affect the accuracy of the exploration data. The team first collected strike-azimuth data of the strata in the exploration area, then deployed a non-uniform gridded electrode array along a direction orthogonal to the dip direction of the strata. Combining the in-situ electrical conduction velocity and anisotropy coefficient of the strata in the exploration area, the spacing between adjacent electrode array nodes was directly determined. Simultaneously, the three-dimensional spatial coordinates of all electrode array nodes were recorded, establishing a one-to-one correspondence between the array node coordinates and the electrode excitation channel and signal acquisition channel, generating an electrode array spatial topology mapping matrix.

[0028] After in-situ electrical signal acquisition is initiated, the contact impedance, signal-to-noise ratio, and electromagnetic attenuation coefficient of the electrode array nodes are monitored in real time across the entire area. When any parameter exceeds the preset range, the amplitude and phase of the electrode excitation current are automatically adjusted to ensure stable signal acquisition. The electrode array node corresponding to the electrical center of the strata in the survey area is selected as the synchronization reference source. Combined with relevant parameters of strata electromagnetic propagation, the acquisition trigger delay compensation and calibration timing reference value of each array node are directly obtained, completing the timing synchronization calibration of the entire array nodes.

[0029] Using the calibrated timing reference as the trigger origin, the in-situ electrical signal is captured non-overlappingly and phase-locked according to a preset frame period. The deviation between the frame's initial phase and amplitude is checked in real time. When the deviation exceeds the limit, adaptive synchronization correction is performed to generate an in-situ signal frame sequence with unified phase and amplitude. The entire timing interval of a single frame signal is traversed to select effective electrical feature bits that meet the constraints of abrupt changes in formation electrical properties. Based on the distribution of feature bits and the discrimination values, the formation response feature area and the environmental interference noise area are divided. Redundant and invalid data in the noise area are removed, and data partitioning and aggregation are completed.

[0030] Using the in-situ stratigraphic baseline electrical parameters of the survey area as a reference, the characteristic position data undergoes nonlinear normalization to eliminate data quantization errors caused by differences in the stratigraphic medium and array layout deviations. The normalized characteristic position data is then used as input, combined with constraints from multiple parameters such as stratigraphic resistivity, relative permittivity, and polarizability, and matched with the spatial topology mapping matrix of the electrode array. This allows for the construction of a three-dimensional analytical model of the stratigraphic electrical parameters across the entire region, directly outputting a distribution tensor of stratigraphic electrical parameters that precisely corresponds to the spatial location of the survey area.

[0031] Finally, using the signal frame time sequence number as the association identifier, the parsed data is aligned frame by frame with the acquired signal frame. The integrated time-series associated dataset is stored in an encrypted manner to verify the temporal continuity and spatial matching degree of the dataset. After detecting data loss, the corresponding electrode array node is controlled to complete in-situ re-acquisition and backfilling of data, thus completing this high-precision, interference-resistant electrical exploration signal acquisition and parsing work.

[0032] In summary, the methods described in the above embodiments, by adapting the electrode array layout to the formation strike and using a time-synchronized acquisition method, conform to the anisotropic characteristics of formation electrical conduction, reduce spatial deviations in signal acquisition, monitor and adjust acquisition parameters in real time, enhance the anti-interference capability and stability of on-site signal acquisition, accurately compensate for signal propagation delays at array nodes, achieve time-series uniformity of acquisition array nodes across the entire domain, perform frame-synchronized interception and dynamic correction on the acquired signals to ensure consistency in signal frame phase and amplitude, accurately screen formation electrical characteristics and process data in zones, effectively filter environmental interference noise, normalize to eliminate data deviations caused by formation differences and layout errors, couple multiple types of formation parameters to complete electrical analysis, and achieve precise time-series binding of acquired and analyzed data, thereby ensuring the stability, continuity, and accuracy of exploration data acquisition and analysis.

[0033] The above embodiments are only used to illustrate the technical solutions of the present invention, and are not intended to limit it. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions will not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A method for anti-interference acquisition and analysis of electrical exploration signals, characterized in that, include: Electrode arrays were deployed according to the stratigraphic strike of the exploration area, the timing coupling reference of the array nodes was calibrated, and in-situ electrical signal acquisition was initiated. According to the calibrated timing coupling reference, the acquired signal is subjected to continuous frame synchronous interception to generate a fixed-length in-situ signal frame sequence; Electrical feature bits are extracted directionally along the time axis of the in-situ signal frame sequence to complete the directional partitioning and aggregation of intra-frame signal data, and the aggregated feature bit data is obtained. The collected feature bit data is normalized in situ to unify the quantization dimension of the intra-frame data and obtain normalized feature bit data. Based on normalized feature bit data, in-situ coupled analytical modeling of formation electrical parameters is performed synchronously. The in-situ coupled analytical modeling data is aligned frame by frame with the corresponding in-situ signal frames generated by the acquisition, thus completing the time-series binding of the acquired and analyzed data.

2. The method for anti-interference acquisition and analysis of electrical exploration signals according to claim 1, characterized in that, When deploying the electrode array according to the stratigraphic strike of the exploration area, the following should be followed: Azimuth data of the strike of strata in the exploration area are collected. Based on the distribution direction of the anisotropic distribution of the electrical conductivity of the strata, a non-uniform gridded electrode array is deployed. The arrangement axis of the array nodes is orthogonal to the dip axis of the strata. The spacing between adjacent array nodes is adjusted according to the electrical conductivity of the strata. The spatial three-dimensional coordinates of each array node are recorded. A one-to-one correspondence between the three-dimensional coordinates of the array nodes and the electrode excitation channel and signal acquisition channel is established, and a spatial topology mapping matrix of the electrode array is generated.

3. The method for anti-interference acquisition and analysis of electrical exploration signals according to claim 2, characterized in that, In the calibration stage of array node timing coupling reference, the electrode array node corresponding to the electrical center of the strata in the survey area is used as the global synchronization reference source. Based on the electromagnetic propagation characteristics of the strata medium, the acquisition trigger delay compensation of each array node is calculated. The timing reference value of each array node is determined according to the delay compensation to complete the global timing synchronization calibration. ； In the formula: This is the calibration timing reference value for the nth array node; The initial synchronization timing values ​​for the reference source array nodes; is the spatial straight-line distance between the nth array node and the reference source array node; The speed of electromagnetic wave propagation in a vacuum; The relative permittivity of the strata in the survey area; The relative magnetic permeability of the formation; The electromagnetic attenuation coefficient of the stratum corresponding to the nth array node is... It is a natural constant; in, This indicates the amount of time delay compensation.

4. The method for anti-interference acquisition and analysis of electrical exploration signals according to claim 1, characterized in that, When performing continuous frame synchronous interception on the acquired signal, the calibrated timing coupling reference is used as the trigger origin. Based on the preset frame period, the in-situ electrical signal is intercepted without overlap and with phase-locked loop. During the interception process, the two-dimensional deviation of the frame start phase and amplitude is checked in real time. When the deviation of either dimension exceeds the preset threshold, adaptive frame synchronization dynamic correction is triggered. Based on the correction amount, the frame start timing is re-locked and the amplitude is normalized and adjusted to generate an in-situ signal frame sequence with consistent phase and amplitude.

5. The method for anti-interference acquisition and analysis of electrical exploration signals according to claim 1, characterized in that, When extracting electrical feature bits along the time-series axis of the in-situ signal frame sequence, the entire time-series range of a single frame signal is traversed. The linkage characteristics of the potential time-series gradient and the formation contact impedance are fused to construct a nonlinear feature discrimination function, and time-series points that satisfy the formation electrical abrupt change constraint are selected as electrical feature bits. ； In the formula: The comprehensive discrimination value of the electrical characteristics of the k-th time-series point; This represents the signal potential value at that point. This is the formation contact impedance value of the electrode corresponding to this point; It is a time-sequential differential unit; Preset constraint coefficients for feature selection; The standard deviation of the background potential fluctuation of a single frame signal; The standard deviation of background fluctuation in contact impedance for a single frame; when When the time point is determined to be a valid electrical characteristic bit, it is considered to be a valid electrical characteristic bit.

6. The method for anti-interference acquisition and analysis of electrical exploration signals according to claim 5, characterized in that, In the directional partitioning and aggregation stage of intra-frame signal data, based on the temporal distribution of effective electrical characteristic bits and the amplitude of comprehensive discrimination value, the intra-frame signal data is divided into the stratum response characteristic area and the environmental interference noise area. The data is collected in partitions and a three-dimensional mapping relationship between characteristic bits, partition data and temporal points is established. Redundant and invalid data that exceed the background fluctuation constraints in the noise area are adaptively removed.

7. The method for anti-interference acquisition and analysis of electrical exploration signals according to claim 1, characterized in that, In the in-situ normalization stage of the collected feature bit data, the in-situ stratigraphic reference electrical parameters of the survey area are used as the constraint benchmark. The dual-dimensional constraints of feature bit amplitude and spatial topological location are integrated, and nonlinear mapping normalization is performed. ； In the formula: This is the normalized quantized value of the potential of the nth characteristic bit. These are the original characteristic potential values ​​before normalization; This serves as the in-situ reference potential for the strata in the survey area. This represents the saturation potential of the formation's electrical response. Preset adjustment coefficients for nonlinear mapping; The spatial radial distance of the array node corresponding to the nth feature bit; The average radial distance between array nodes; It is the hyperbolic tangent function.

8. The method for acquiring and analyzing electrical exploration signals according to claim 7, characterized in that, The ∈[0.5, 2], when the electrical heterogeneity of the stratum increases or the spatial arrangement deviation of the electrode array increases. The value increases accordingly when the stratum electrical properties are uniform and the electrode array is laid out with high precision. The value decreases accordingly.

9. The method for anti-interference acquisition and analysis of electrical exploration signals according to claim 8, characterized in that, In the in-situ coupled analytical modeling stage of formation electrical parameters, normalized eigenvalue quantization data are used as input. Multi-parameter constraints of formation resistivity, dielectric constant, and polarizability are coupled, and combined with the spatial topology mapping matrix of the electrode array, a three-dimensional coupled analytical model of global formation electrical parameters is constructed. The model solver outputs a formation electrical parameter distribution tensor that corresponds one-to-one with the spatial location of the survey area. ； In the formula: Spatial coordinates The distribution tensor of formation electrical parameters at the location; This is the spatial topology mapping matrix of the electrode array; Spatial coordinates The resistivity of the formation at that location; Let be the relative permittivity of the formation at spatial coordinates (x, y, z); Spatial coordinates The formation polarization at that location; Spatial coordinates The spatial gradient vector of the electromagnetic attenuation coefficient at that location; This represents the temporal rate of change of formation polarizability.

10. The method for anti-interference acquisition and analysis of electrical exploration signals according to claim 8, characterized in that, The time-series binding operation for the acquisition and parsing of data follows the following: Using the global time series number of the in-situ signal frame as the unique association identifier, the tensor data of formation electrical parameter distribution is precisely aligned frame by frame with the corresponding signal frame in both spatial and temporal dimensions. The aligned data is then encrypted end-to-end using the AES-256 symmetric encryption algorithm to generate an integrated time series association dataset, which is written to the local encrypted storage medium. The temporal continuity of the dataset is verified based on the preset time series sampling interval, and the spatial matching degree of the dataset is verified based on the electrode array spatial topology mapping matrix. When the time series interval between two consecutive frames of data exceeds the sampling interval threshold or the electrical parameter data corresponding to the spatial coordinates is null, it is determined that the data is missing. When the data is missing, a directional in-situ supplementary sampling command is triggered. The directional in-situ data acquisition instruction includes the timing number, spatial coordinate array node, excitation current parameter, and acquisition duration parameter corresponding to the missing data, which controls the corresponding electrode array node to perform in-situ data acquisition and backfill the missing data.

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