150 results about "Apparent resistivity" patented technology

The invention discloses a dam leakage channel detection and danger elimination quality evaluation method based on transient electromagnetism, and relates to the technical field of earth and rockfill dam danger elimination and reinforcement. The method comprises the following steps: A, leakage channel detection: A1, data acquisition: performing data acquisition on a dam by adopting pull-type small loop transient electromagnetic equipment to obtain original electromagnetic signal data; a2, forward modeling: performing forward modeling on the acquired data, and calculating a theoretical attenuation curve and apparent resistivity distribution by considering special boundary conditions of the dam; and A3, carrying out inversion calculation. According to the method, leakage signals can be accurately captured based on the high sensitivity of a transient electromagnetic method to a low-resistance body, the used pull-type small-loop transient electromagnetic equipment is convenient to operate, a dam can be comprehensively covered by combining reasonable measurement point arrangement, forward modeling and inversion calculation can comprehensively consider various factors, the position and depth of a leakage area are determined, and the detection accuracy is improved. Compared with a traditional method, the method has obvious advantages in detection depth and accuracy.

The invention provides a grouting diffusion three-dimensional monitoring system and method and a medium, and relates to the technical field of railway roadbeds, and the system comprises an acquisition module and a data processing module; the acquisition module is used for acquiring apparent resistivity corresponding to a grouting diffusion area in a railway roadbed in parallel; and the data processing module is connected with the acquisition module and is used for performing forward modeling and inversion according to a preset geoelectric model and the apparent resistivity to obtain a three-dimensional apparent resistivity map representing the grouting diffusion range. Thus, on one hand, the collection efficiency of apparent resistivity is improved, on the other hand, a three-dimensional apparent resistivity map can be obtained, three-dimensional real-time monitoring of the slurry flow path, the flow range, the spatial and temporal distribution and the occurrence state in the grouting process is achieved, the slurry diffusion condition is accurately and visually reflected, and the grouting quality is improved. And a basis is provided for grouting reinforcement mechanism research, technical development and scheme optimization.

The invention belongs to the technical field of earth and rockfill dam deep burying disease identification and positioning, and discloses an earth and rockfill dam leakage channel comprehensive detection method and system, and the method comprises the steps: determining the distribution of detection points detected by an electrical method, and collecting the apparent resistivity data and the apparent polarizability data of the detection points; inverting apparent resistivity and apparent polarizability data to obtain a resistivity profile and a polarizability profile, and obtaining a normalized polarizability profile based on the resistivity profile and the polarizability profile; performing stratum zoning on the to-be-detected area based on the section, determining the soil cation exchange capacity and the cementation index of the zoned stratum, and calculating the soil water content and the permeability of the measured section according to the normalized polarizability, the soil cation exchange capacity and the cementation index; and determining an earth and rockfill dam leakage channel according to a water content and permeability judgment mechanism. According to the method, the uncertainty of a single physical property threshold value method is overcome, and the accuracy and precision of the leakage hidden danger of the earth and rockfill dam are improved.

The invention relates to the technical field of data processing, discloses an earth and rockfill dam leakage positioning method based on joint inversion and data fusion, and aims to solve the problems of limitation and non-uniqueness of an existing single geophysical prospecting method in leakage hidden danger positioning. Converting the first apparent resistivity into a first apparent resistivity; second apparent resistivity distribution of the earth-rock dam is obtained through a high-density electrical method; acquiring electromagnetic wave velocity distribution by adopting a ground penetrating radar method, and converting the electromagnetic wave velocity distribution into third apparent resistivity; performing data standardization processing on the apparent resistivity to obtain standardized apparent resistivity data; performing dimension reduction fusion on the standardized apparent resistivity data corresponding to each apparent resistivity by adopting a principal component analysis method to obtain simulated apparent resistivity distribution; and determining the position of the leakage hidden danger channel in the earth-rock dam based on the pseudo-apparent resistivity distribution. The method improves objectivity, accuracy and reliability of leakage positioning, and is particularly suitable for danger removal and reinforcement of earth and rockfill dams.

The invention relates to the field of geophysical electromagnetic exploration, and provides a time-frequency electromagnetic data processing method, device, equipment and medium, and the method comprises the steps: calculating the similarity offset ratio of each measuring point on a measuring line, and determining a static displacement measuring point on the measuring line based on the similarity offset ratio; calculating equivalent apparent resistivity ratio of static displacement measurement point based on equivalent apparent resistivity of electric field component and corrected equivalent apparent resistivity of magnetic field component corresponding to adjacent measurement points on left and right sides of static displacement measurement point, and updating equivalence of electric field component of static displacement measurement point based on equivalent apparent resistivity ratio and corrected equivalent apparent resistivity of magnetic field component apparent resistivity; and completing static displacement correction in response to the static displacement measuring points on the measuring line, and performing inversion calculation on the magnetic field component amplitude and the electric field component amplitude of each measuring point on the measuring line to obtain resistivity distribution of a preset depth below the measuring line. The scheme disclosed by the invention is beneficial to improving the exploration and prediction precision of the time-frequency electromagnetic oil and gas target.

The invention discloses a tunnel shield interval boulder prediction method, medium and equipment, and the method comprises the steps: S1, obtaining the high-density electrical method apparent resistivity data of a detection region, and carrying out the inversion to obtain an apparent resistivity two-dimensional profile; s2, integrating the two-dimensional profile into a three-dimensional space, and constructing a continuous three-dimensional resistivity data volume; s3, extracting a threshold value abnormal region according to a preset threshold value A, and determining a boulder suspicious region A; s4, background signal propagation characteristics of the boulder-free area are measured through ultrasonic waves, a threshold value B is set, and if the background signal propagation characteristics exceed the threshold value B in the actual measurement process, the boulder-free area is marked as a boulder suspicious area B; and S5, obtaining an intersection of the abnormal coordinates of the boulder suspicious area A and the boulder suspicious area B, generating a closed three-dimensional boulder suspicious area, and outputting a result in a three-dimensional visualization manner. According to the method, the problems of high false anomaly rate, insufficient spatial information, strong subjective dependence and the like of a traditional single geophysical prospecting method are systematically solved, and the accuracy, the reliability and the engineering applicability of boulder detection are remarkably improved.

The invention discloses a method for identifying logging interpretation electrical standard parameters, and solves the problems of inaccurate difference and low efficiency caused by the influence of subjective factors on the manual identification result of the logging interpretation electrical standard parameters in the prior art. The method comprises the following steps: S1, establishing a benchmarking array for a well section to be identified; s2, matching the target well data on the apparent resistivity curve A based on the established benchmarking array; obtaining optimal matching data; s3, determining a reference layer identified by the electrical standard; s4, identifying a microsphere standard, a sound wave calcium judgment standard and a deep three lateral standard; s5, identifying a microelectrode standard; and S6, identifying a micro-gradient calcium judgment standard. The device for realizing the automatic identification of the logging interpretation electrical standard parameters comprises an establishing unit; a matching unit; a determination unit; a first identification unit; a second identification unit; and a third identification unit. According to the method, logging interpretation electrical standard parameters can be rapidly identified, and quality improvement and efficiency improvement of logging interpretation reservoir thickness division work are assisted.

The invention provides a deep and large fracture depicting method based on low-frequency electromagnetic information recovery enhancement, and the method comprises the steps: S1, collecting electromagnetic data, and carrying out the preprocessing of the electromagnetic data, and obtaining the preprocessed electromagnetic data; s2, obtaining frequency domain apparent resistivity and phase according to the preprocessed electromagnetic data; s3, establishing a shallow stratum electrical model; s4, acquiring a depth domain apparent resistivity profile according to the shallow stratum electrical model; and S5, depicting deep and large fracture distribution based on the depth domain apparent resistivity profile. According to the invention, enhancement of low-frequency electromagnetic signals is realized, the inversion precision of electromagnetic data is improved, low-frequency geological information is effectively recovered, and deep and large fractures can be effectively described.

The application provides a three-dimensional geological modeling method and system for ductile shear zone type gold exploration, and relates to the technical field of gold exploration modeling. The application extracts a plurality of alteration anomaly zones related to gold mineralization hydrothermal alteration by acquiring multispectral remote sensing data of an exploration area; superimposes the anomaly zones to identify a prospecting target area and acquire electrical parameter data such as apparent resistivity and apparent polarization rate; determines the structural geological distribution in combination with surface geological mapping, divides a prospecting unit in space superposition with the target area, sets the electrical parameter range to establish a three-dimensional prospecting unit framework; and obtains the three-dimensional distribution of electrical parameters and the geological unit boundary by jointly inverting the electrical parameters as measured data, the framework and the parameter range, generates a three-dimensional geological model reflecting the spatial distribution of the gold mineralization body, and can accurately depict the spatial distribution of the ductile shear zone type gold mineralization body, thereby supporting efficient exploration.

The application discloses a global apparent resistivity iterative initial value setting method, device, medium and product, relates to the electromagnetic detection technical field, and the method comprises the following steps: firstly, a plurality of rough estimated resistivity values are selected in a predetermined resistivity range according to logarithmic equal intervals, and a corresponding rough estimation resistivity model is constructed accordingly. Then, the transient electromagnetic response of each rough estimation model on different time channels is calculated, and compared with the actually measured transient electromagnetic response, so that the response deviation value of the model is obtained. According to this, the preliminary resistivity initial value is selected. Subsequently, the transient electromagnetic response of several time channels of the shallow layer is fitted, and a more accurate resistivity estimation value is obtained. Based on these fine estimation resistivity values, the fine estimation resistivity initial value of each time channel is further calculated. Finally, for any one time channel, the transient electromagnetic response thereof is fitted, and the final resistivity initial value of the time channel is determined by taking minimizing the difference between the actual measured value and the predicted value as the target.

The present invention discloses a multi-scale electromagnetic exploration method based on single-electrode potential detection, which relates to the field of exploration geophysical technology. The method includes: determining the measurement area, clarifying the exploration target, and determining the measurement area and measurement point density based on the depth of the exploration target; deploying a number of transmitting sources and receiving arrays in the measurement area to collect surface potential data of the measurement area in real time, and processing the data frequency by frequency according to a preset frequency sequence; generating a surface potential distribution surface based on the single-electrode potential data, constraining and suppressing the field source effect, obtaining electric field distribution information of the measurement surface, and calculating apparent resistivity parameters in combination with magnetic field measurement data; using a multi-directional excitation mode and a multi-source emission scheme to suppress the field source effect, and constructing a three-dimensional resistivity profile to identify low-resistance or high-resistance bodies. The present invention solves the static effect and volume effect, breaking through the limitations of existing electromagnetic instruments on detection accuracy and depth.

The application discloses a kind of based on the combination of detection and simulation's structural feature analysis method, belongs to fault structural feature analysis field, comprising the following steps: first, by combining early part drilling and known data to predict possible results, and establish numerical model for each possibility to carry out electrical method analysis, obtain apparent resistivity spatial distribution model by analysis calculation;Then, the actual apparent resistivity spatial distribution model is obtained by carrying out electrical measurement in the field;The result figure obtained by numerical simulation is compared with the actual result, and is corrected, to determine more accurate geological structure.The application adopts the above-mentioned structural feature analysis method based on the combination of detection and simulation, realizes the combination of detection and simulation, based on the result of numerical analysis is constantly corrected, so as to obtain exact fault structural feature.

The invention provides an apparent resistance correction method and system based on a resistivity method, a medium and equipment, and relates to the technical field of electric field detection. According to the technical scheme provided by the invention, the intra-group control scheme is generated by matching the preset optimization target corresponding to the attribute tag, adjustment is performed according to the inter-group influence factors to form the target control scheme, and the measurement strategy can be adaptively adjusted according to the geologic features. After the vector receiving voltage is acquired, vector synthesis is performed on the initial apparent resistance according to the horizontal included angle to obtain the target apparent resistance, so that the problem that a single component signal is weak and is easily interfered by noise in a traditional resistivity method is effectively solved. When component signals in a certain direction are particularly weak or abnormal, negative apparent resistivity can be avoided by adopting a vector synthesis mechanism, and the data stability is improved. The convergence of the inversion algorithm and the stability of the solution are obviously improved by improving the quality of the final input data and fully utilizing the vector information, vector synthesis can be carried out on component signals, and the inversion effect of the resistivity method is improved.

The invention belongs to the technical field of geophysical exploration, and discloses a mine transient electromagnetic anomaly boundary identification method based on DBSCAN clustering. The method comprises the following steps: step 1, establishing a three-dimensional geophysical model; 2, calculating apparent resistivity data by using a small loop transient electromagnetic method; 3, drawing a k-distance map, and obtaining an optimal neighborhood radius according to the k-distance map; step 4, performing DBSCAN clustering on the apparent resistivity data to obtain a clustering result; 5, replacing the intra-cluster apparent resistivity value with a cluster center value to obtain replaced apparent resistivity data; step 6, imaging the replaced apparent resistivity data and identifying an abnormal body; 7, comparing the anomalous body boundary with the anomalous body boundary in the model, and if the difference is too large, adjusting the optimal neighborhood radius and returning to the step 4; and otherwise, taking the current abnormal body as a final identified abnormal body. The method can effectively identify irregular anomalous body boundaries of non-uniform complex stratums, and can adapt to real-time identification requirements of underground anomalous bodies.

The application provides a resistivity-based apparent resistivity correction method, system, medium and equipment, and relates to the technical field of electric field detection. The technical scheme provided by the application generates an in-group control scheme by matching a preset optimization target corresponding to an attribute label, adjusts a target control scheme according to inter-group influencing factors, and can adaptively adjust a measurement strategy according to geological characteristics. After collecting a vector receiving voltage, the initial apparent resistivity is vector synthesized according to a horizontal angle to obtain a target apparent resistivity, effectively solving the problem that a single component signal is weak and susceptible to noise interference in the traditional resistivity method. When a certain direction component signal is particularly weak or abnormal, the vector synthesis mechanism can avoid the appearance of negative apparent resistivity, improving data stability. The improvement of the final input data quality and the full use of vector information significantly improve the convergence of the inversion algorithm and the stability of the solution, can perform vector synthesis on the component signal, and improve the inversion effect of the resistivity method.

The invention discloses an anomalous body positioning method and system combining borehole transient electromagnetic and geological radar, and relates to the technical field of mine safety detection, and the method comprises the steps: synchronously collecting the borehole transient electromagnetic data and geological radar data of an ore body to be analyzed, and generating a borehole transient electromagnetic imaging graph and a borehole geological radar imaging graph; two-dimensional coordinates of a target abnormal point in the borehole geological radar imaging graph are extracted, and the corresponding target apparent resistivity is determined; drawing an apparent resistivity contour map based on the target apparent resistivity in a target radial sectioning map of the borehole transient electromagnetic imaging map, and determining a plurality of candidate three-dimensional coordinates of a target abnormal point; at least one target feature point is selected from the borehole geological radar imaging graph, and the feature apparent resistivity corresponding to the target feature point is determined; and drawing a feature circle based on the target feature points, and screening the plurality of candidate three-dimensional coordinates to obtain coordinates of the geological anomalous body. According to the invention, the technical problem of insufficient positioning precision and reliability in the prior art is solved.

The present application relates to the engineering geophysical exploration technical field, specifically to a kind of complex terrain direct current resistivity three-dimensional forward and inversion method and system based on octree;Method includes: establishing target information sequence;Three-dimensional geoelectric model based on octree grid is constructed using target information sequence, and local encryption is carried out in the surface near the detection area and electrode neighborhood, and the modeling result is output;Based on the modeling result, the underground active unit located below the terrain surface and the air unit located above the terrain surface are distinguished, the finite volume method is used to discretize and solve the direct current resistivity method potential field control equation of underground active unit, the theoretical potential response corresponding to electrode device is obtained, and the theoretical apparent resistivity response is obtained;Construct inversion objective function, and iteratively update resistivity parameters of three-dimensional geoelectric model using inversion strategy;The three-dimensional resistivity imaging result of underground medium in detection area is output through updated three-dimensional geoelectric model, and adverse geological body is identified.

The application relates to an exploration method based on frequency division electrical method of variable frequency signals and belongs to the technical field of electrical exploration, which comprises the following steps: determining the frequency value and the frequency quantity of each channel of a multi-channel frequency division electrical method transmitter based on an exploration purpose and exploration requirements; transmitting variable frequency signals to the underground by each channel of the multi-channel frequency division electrical method transmitter; obtaining the current value of each frequency transmitted by each channel of the multi-channel frequency division electrical method transmitter at a mobile power supply point; obtaining the potential difference of different frequencies measured by a multi-channel frequency division electrical method receiver at a measuring electrode pair and the phase difference of the potential difference of the corresponding frequency relative to the current of the same frequency power supply; determining the device coefficient based on the coordinates of the measuring electrode pair and all the mobile power supply points; calculating the apparent resistivity based on the apparent resistivity parameter formula corresponding to the electrode device; and obtaining the exploration interpretation result based on the apparent resistivity and the phase difference. The application has the effect of comprehensively and accurately collecting geoelectric information.

The invention belongs to the technical field of geophysical exploration, and provides a tunnel geological disaster advanced prediction method and system based on an orthogonal field source, and the method comprises the steps: constructing two groups of high-order pseudo-random signals, laying the orthogonal field source, and enabling the field source to transmit different groups of high-order pseudo-random signals; two groups of orthogonal observation points are arranged on a tunnel face and a tunnel bottom plate within a set distance, two field sources are excited at the same time, the two groups of observation points observe and collect received signals within set duration respectively, and electromagnetic field data of the corresponding field sources are extracted according to frequency components of emitted high-order pseudo-random signals; and according to the electromagnetic field data, calculating the single-component electric field apparent resistivity and the Kania apparent resistivity to obtain a detection result. According to the invention, the geological condition of the tunnel construction site can be detected.

The present application relates to the technical field of electromagnetic sounding, in particular to a multi-step variation AB-Hy encoding electromagnetic sounding one-dimensional inversion method and device, for the measured AB-Hy encoding electromagnetic sounding full area apparent resistivity observation value, the method presets the feasible solution space of one-dimensional horizontal layered model, randomly generates a population, forward calculation of the full area apparent resistivity of each individual in the population, calculates the fitness value of each individual in the population according to the full area apparent resistivity calculation value and observation value of each individual;Select the individual with the highest current fitness value as the optimal individual, and perform iterative calculation of multi-step differential evolution with the optimal individual participating in the population individual;The individual with the highest fitness value obtained is taken as the inversion result of the observation data. AB-Hy electromagnetic sounding one-dimensional inversion based on multi-step differential evolution algorithm is realized, the geoelectric model parameters corresponding to the observation data are obtained, and the basis for geological interpretation is provided. The method has fast optimization convergence speed and high accuracy of inversion result.

This invention discloses a wide-azimuth artificial source electromagnetic observation method, device, and medium. The method includes: selecting the construction area of ​​the detection task as the measurement area according to the preset detection task requirements; determining the minimum distance between the field source and the measurement area according to the induction number requirement, and determining the maximum distance between the field source and the measurement area according to the signal-to-noise ratio requirement, and then defining the annular area formed between the minimum and maximum distances between the field source and the measurement area as the field source area; arranging measurement points in the measurement area, and arranging field sources in the field source area; collecting data of any electromagnetic field component at the measurement points and recording the corresponding device acquisition parameters; and using the electromagnetic field component data and the device acquisition parameters, solving for the apparent resistivity using an iterative method. This invention can deploy field sources in all azimuth angles of the measurement area and observe all electromagnetic field components, providing great flexibility in the selection of field source locations and data acquisition.

The application relates to the technical field and discloses a method and system for measuring and calculating apparent resistivity of horizontally layered earth, wherein a characteristic equation of horizontally layered earth is constructed according to an integral variable set obtained through an exponential discrete sampling method and horizontally layered earth parameters; an uplink electromagnetic wave amplitude kernel function of the characteristic equation at each integral variable is calculated to obtain an integral upper limit of horizontally layered earth, and the integral upper limit of horizontally layered earth is set as the maximum value of the integral variable satisfying a preset criterion; based on the integral upper limit of horizontally layered earth, the integral range of the constructed apparent resistivity relationship formula of an unbounded domain is limited to obtain an apparent resistivity relationship formula of a bounded domain; and based on a 151-point Gauss-Legendre integral algorithm and Euler transformation, the apparent resistivity relationship formula of the bounded domain is iteratively solved to obtain a measurement and calculation result of the apparent resistivity. The method meets the dual requirements of precision and efficiency for the measurement and calculation of the apparent resistivity of horizontally layered earth.

The invention relates to a borehole transient electromagnetic detection system and method for orthogonal three-direction overlapped loops, and belongs to the field of underground coal mine borehole transient electromagnetic detection. In order to solve the problem that in the prior art, due to the fact that the directions of transmitting and receiving antennas are not matched, the overlapping loop theory cannot be directly applied, formula approximate calculation needs to be corrected, and the precision is reduced, three groups of transmitting and receiving antennas which are mutually orthogonal and perpendicular are arranged in a probe tube, and each group of antennas works in an overlapping loop mode; and the control unit controls the three groups of coils to sequentially transmit signals and receive responses. According to the invention, accurate inversion of the apparent resistivity is realized by directly applying an overlapped loop apparent resistivity formula; and through combination of tool face angle rotation detection and three-dimensional interpolation processing, hole periphery complete apparent resistivity space imaging is formed. The method has the beneficial effects that formula correction errors are eliminated, and the low-resistance anomalous body recognition precision is improved; full-space three-dimensional high-resolution detection is realized; the process is simplified; and the reliability of the system in an underground complex environment is enhanced.

The invention provides a coal mine extremely shallow goaf geophysical prospecting data analysis method based on a transient electromagnetic method, which is characterized by comprising the following steps of: optimizing data acquisition parameters and correcting terrain; data preprocessing and noise suppression are carried out, multi-stage preprocessing is carried out on the original data, and preprocessing comprises outlier elimination, filtering noise reduction, null drift correction and background field deduction; time-depth conversion and resistivity inversion are carried out; quantitative analysis of goaf response characteristics; carrying out three-dimensional data fusion and visual modeling, integrating multi-measuring-line data and geological information, and constructing a goaf space distribution model; and the conclusion reliability is improved through field drilling verification and error source analysis. Aiming at the detection difficulty of an extremely shallow goaf, electromagnetic response details of a shallow medium are captured through small coil high-frequency excitation and microsecond-level signal acquisition. The terrain laser correction and the whole-period apparent resistivity inversion are combined, so that the tiny holes are accurately identified; and through drilling entity verification and error simulation, the misjudgment rate is remarkably reduced.

This invention belongs to the field of horizontal well logging interpretation and evaluation technology. It proposes a correction method, system, and equipment based on dual-lateral logging layer thickness-surrounding rock. The method includes: determining the positional relationship between the top and bottom interfaces of the horizontal wellbore in the target layer; determining the trajectory factor based on the positional relationship of the top and bottom interfaces; determining the measured shallow and deep dual-lateral apparent resistivity based on the trajectory factor, the true resistivity of the target layer, the surrounding rock resistivity, and the target layer thickness, and constructing a dual-lateral logging layer thickness-surrounding rock correction database; and substituting the trajectory factor, surrounding rock resistivity, target layer thickness, and measured shallow and deep dual-lateral apparent resistivity into the correction database to perform inversion correction on the true resistivity of the target layer, obtaining the corrected target layer resistivity. The introduction of continuous trajectory factors and a numerical iterative inversion method compensates for the correction errors caused by previous fixed ratio interpolation calculations. Verification has shown that the influence of wellbore trajectory, target layer thickness, and surrounding rock is eliminated.

The invention relates to the technical field of deep rock mechanics, and provides a deep in-situ environment rock parameter acoustic electromagnetic fidelity test system and method.The deep in-situ environment rock parameter acoustic electromagnetic fidelity test system comprises a cabin, a test space is formed in the cabin, and a rock core sample enters the test space from one end of the cabin through a displacement unit; the temperature and pressure control unit is communicated with the cabin body and is used for adjusting the temperature and the pressure in the cabin body to reach target values and keeping the target values stable; the acoustic electromagnetic testing module is arranged in the cabin body and used for calculating the wave velocity, the resistivity and the apparent resistivity of the rock core sample, and the acoustic electromagnetic testing module is connected with an external acoustic electromagnetic data acquisition system; and the remote control system is electrically connected with the acoustic electromagnetic test module and the temperature and pressure control unit. According to the method, the original occurrence state of the rock can be restored in a fidelity manner, the physical and mechanical parameters of the rock in a deep in-situ real environment are tested and analyzed, the evolution law of the physical and mechanical parameters along with the deep environment is analyzed, and reliable data support is provided for revealing the constitutive relation, the failure mechanism and the disaster breeding mechanism of the deep rock mass.

The embodiment of the invention relates to the field of electric or magnetic exploration or detection, in particular to a method and system for determining the extension form of a fracture deep part of a granite type uranium mine. According to the method and the system, the relation between the electrical difference and the underground geologic structure can be quantified by determining the relation between the electrical resistivity of the fracture area and the electrical resistivity of the peripheral area of the fracture area; an underground resistivity inversion cross-section diagram is determined according to the frequency-apparent resistivity of each measuring point, and the deep extension form of the fracture can be visually judged; according to the method, the frequency-apparent resistivity at the measuring point is determined only by using the electric field signal, so that the calculation result is more accurate; and in combination with an underground resistivity inversion section diagram of a detection section, the deduction of the deep extension form of the fracture can be more accurate.

The application provides a layered medium detection method based on an electromagnetic field, a storage medium and an electronic device, including: obtaining electric field data and magnetic field data of a target to be detected; determining impedance of the target to be detected, and determining an apparent resistivity curve of the target to be detected; determining a resistivity value of a current first layer medium of the target to be detected based on the apparent resistivity; determining a thickness of the current first layer medium of the target to be detected based on the apparent resistivity curve of the target to be detected and the resistivity value of the current first layer medium; and performing layer-by-layer impedance stripping on the target to be detected based on the resistivity value and the thickness of the current first layer medium, to determine a resistivity value and a thickness of each layer medium of the target to be detected. The method effectively calculates the thickness and resistivity of each layer medium by layer-by-layer stripping of each layer medium of the target to be detected, realizes layered medium detection of the target to be detected, and has the advantages of non-contact, no pollution, low cost, simple operation, high speed and no need of coupling.

The application discloses a method and system for predicting the occurrence depth of an ore body of a weathered crust type rare earth deposit, and relates to the technical field of geological exploration. The method comprises the following steps: performing on-site testing on the weathered crust by using a high-density electrical method; calculating and inverting the testing results to obtain apparent resistivity data of the weathered crust at different depths; correcting the distortion values of the apparent resistivity data with the terrain fluctuation according to the terrain of the weathered crust, obtaining the apparent resistivity data of the weathered crust at different depths after the terrain correction by using a ratio method, and further obtaining a first derivative curve of the apparent resistivity changing with the depth, and determining the occurrence depth of the rare earth ore body in combination with a logistic regression model parameter. The application uses the variation law of the apparent resistivity of the weathered crust at different depths to find out the groundwater structure of the weathered crust, further uses the logistic regression model parameter to determine the position of the ore body of the weathered crust type rare earth deposit, so as to accurately predict the occurrence depth of the rich ore layer of the weathered crust type rare earth deposit, and efficiently and accurately explore the rare earth ore body in the weathered crust.

The invention relates to a borehole transient three-dimensional imaging method, belongs to the technical field of geophysical exploration, and aims to solve the technical problem that accurate quantitative three-dimensional imaging cannot be realized when a plurality of low-resistance anomalous bodies exist around a borehole in an existing borehole transient electromagnetic method. According to the technical scheme, the method comprises the following steps: collecting transient electromagnetic signals at a single measuring point in a drill hole by using a transmitting coil and an orthogonal three-component receiving coil; dividing the radial direction into four azimuth areas, and establishing an equation set to solve the induced voltage of each area; calculating apparent resistivity by adopting a late apparent resistivity formula based on the voltage value; generating a radial two-dimensional plane apparent resistivity map through interpolation; and moving to a plurality of measuring points along the axial direction of the drill hole, repeating the steps and carrying out continuous interpolation, and finally generating a three-dimensional apparent resistivity image. The method has the technical effects that the accuracy and practicability of a detection result are remarkably improved, and the imaging requirements of a plurality of low-resistance bodies in complex geological environments such as underground coal mines are effectively met.