Soil resistivity correction method and device, equipment and storage medium

Abstract

The invention discloses a soil resistivity correction method, device and equipment and a storage medium, and the method comprises the steps: firstly obtaining a preset logging current, a first electrode voltage and a preset first polar distance of a logging method, and a contact area, a thickness, a preset polar plate voltage and a sampling current of a sampling method in a to-be-measured region; a plurality of preset second polar distances, preset quadrupole current and second electrode voltage of the quadrupole method; constructing a first resistivity formula, a second resistivity formula and a third resistivity formula according to the acquired data; according to the first weight, the second weight, the third weight, the first resistivity formula, the second resistivity formula and the third resistivity formula, a corrected soil resistivity formula is obtained through calculation; and obtaining the depth to be measured, and calculating the corrected soil resistivity at the depth to be measured according to the depth to be measured and the soil resistivity formula. According to the invention, measurement errors caused by a logging method, a sampling method and a quadrupole method can be reduced.

Description

Technical Field

[0001] The present invention relates to the technical field of resistivity correction, and in particular to a soil resistivity correction method, device, equipment and storage medium. Background Art

[0002] During the planning and construction of the terminal station grounding system, due to factors such as the soil resistivity measurement error at the station site, there is a large error between the actual value of the grounding network impedance after completion and the design value, which will make the grounding characteristics and safety performance fail to meet the requirements. Currently, there are few studies on the correction and modeling of soil resistivity test results in urban areas, and accurate soil resistivity is very important for the construction of 500kV terminal stations.

[0003] Currently in the power industry, the quadrupole method, sampling method and well logging method are usually used to measure the soil resistivity of planned urban areas. However, there are a large number of metal conductors underground in urban areas. These conductors will affect the electromagnetic field in the ground, making the soil resistivity appear to be smaller when the quadrupole method is used to measure the soil resistivity, causing errors in the measurement results. The sampling method will also have errors due to the limited samples taken. The well logging method can only reflect the soil conditions of the well wall because the measurement is carried out in the well, which will cause errors due to the small measurement range. Summary of the invention

[0004] The invention provides a soil resistivity correction method, device, equipment and storage medium, which can reduce the error generated when measuring soil resistivity by a single sampling method, a well logging method or a quadrupole method.

[0005] An embodiment of the present invention provides a method for correcting soil resistivity, comprising:

[0006] The preset logging current, first electrode voltage and preset first electrode distance of the logging method in the test area, the contact area, thickness, preset electrode plate voltage and sampling current of the sampling method, and several preset second electrode distances, preset quadrupole current and second electrode voltage of the quadrupole method are obtained; wherein, the well is drilled down to a preset depth in the test area, and several portions of rock from the surface to the preset depth are obtained at preset intervals to obtain the thickness of each portion of rock, and conductive electrode plates are placed on both sides of each portion of rock to contact with each other to obtain the contact area between the conductive electrode plate and the rock, and the sampling current of the rock at each depth is measured after the preset electrode plate voltage is passed; the first A grounding electrode, a second grounding electrode and a power supply, wherein one end of the power supply is connected to the first grounding electrode, the other end of the power supply is connected to a power supply electrode extending into the wellbore to a preset depth, and the second grounding electrode is connected to a receiving electrode extending into the wellbore and having a preset first pole distance from the power supply electrode; a preset logging current is passed through the power supply electrode to measure the first electrode voltage at each depth between the receiving electrode and the second grounding electrode; a first current electrode, a first voltage electrode, a second voltage electrode and a second current electrode are sequentially arranged along a straight line in the above-mentioned test area according to a preset second pole distance, a preset quadrupole current is passed through the first current electrode, and a second electrode voltage corresponding to each preset second pole distance is obtained;

[0007] Constructing a first resistivity formula, a second resistivity formula and a third resistivity formula according to the preset logging current, the first electrode voltage, the preset first electrode distance, the contact area, the thickness, the preset electrode plate voltage, the sampling current, the preset second electrode distance, the preset quadrupole current and the second electrode voltage;

[0008] According to the first weight, the second weight, the third weight, the first resistivity formula, the second resistivity formula and the third resistivity formula, a modified soil resistivity formula is calculated; wherein, an importance scale significance table is obtained, a judgment matrix is ​​constructed according to the importance scale significance table, and the maximum eigenvalue of the judgment matrix and the eigenvector corresponding to the maximum eigenvalue are calculated according to the judgment matrix; the eigenvector is normalized to obtain the first weight, the second weight and the third weight;

[0009] The depth to be measured in the measured area is obtained, and the corrected soil resistivity at the depth to be measured is calculated according to the depth to be measured and the soil resistivity formula.

[0010] Further, the first resistivity formula, the second resistivity formula and the third resistivity formula are constructed according to the preset logging current, the first electrode voltage, the preset first electrode distance, the contact area, the thickness, the preset electrode plate voltage, the sampling current, the preset second electrode distance, the preset quadrupole current and the second electrode voltage, including:

[0011] Constructing a first resistivity formula according to the preset logging current, the first electrode voltage and the preset first electrode distance;

[0012] Constructing a second resistivity formula according to the contact area, thickness, preset plate voltage and sampled current;

[0013] A third resistivity formula is constructed according to the above-mentioned preset second pole distance, preset quadrupole current and second electrode voltage.

[0014] Furthermore, the first resistivity formula is constructed according to the preset logging current, the first electrode voltage and the preset first electrode distance, including:

[0015] Calculating the first resistivity at each depth according to the preset logging current, the first electrode voltages and the preset first electrode distance;

[0016] A first resistivity formula is constructed according to the first resistivity and the depth corresponding to the first resistivity.

[0017] Furthermore, the second resistivity formula is constructed based on the contact area, thickness, preset plate voltage and sampled current, including:

[0018] The second resistivity at each depth is calculated based on the contact area, thickness, preset plate voltage and sampled current;

[0019] A second resistivity formula is constructed according to the second resistivity and the depth corresponding to the second resistivity.

[0020] Furthermore, the third resistivity formula is constructed according to the preset second pole distance, the preset quadrupole current and the second electrode voltage, including:

[0021] According to each of the above-mentioned preset second pole distances, the preset quadrupole current and the second electrode voltage, a third resistivity corresponding to each of the above-mentioned preset second pole distances is calculated;

[0022] The third resistivity, the preset second pole distance corresponding to the third resistivity, the preset quadrupole current and the second electrode voltage are inverted to obtain the third resistivity at each depth, and then the third resistivity formula is obtained.

[0023] Furthermore, the maximum eigenvalue of the judgment matrix and the eigenvector corresponding to the maximum eigenvalue are calculated according to the judgment matrix, including:

[0024] Normalizing all elements of the above judgment matrix by columns to obtain a normalized first judgment matrix;

[0025] Calculate the sum of the elements in each row of the first judgment matrix, and use the sum as the element of the row where each sum in the first judgment matrix is ​​located, to obtain a second judgment matrix;

[0026] According to the second judgment matrix and the judgment matrix, the maximum eigenvalue and the eigenvector are calculated;

[0027] Among them, each element of the first judgment matrix is ​​calculated according to the following formula:

[0028]

[0029] In the formula, represents the i-th row and j-th column element in the first judgment matrix above, a ij represents the i-th row and j-th column element in the above judgment matrix, a kj represents the kth element in the jth column to be normalized in the above judgment matrix;

[0030] The above maximum eigenvalue is calculated according to the following formula:

[0031]

[0032] In the formula, λ max represents the maximum eigenvalue, A represents the above judgment matrix, represents the element of the i-th row of the second judgment matrix, ω represents the eigenvector, n represents the n-th row, (Aω) i Represents the product of the i-th judgment matrix and the eigenvector.

[0033] Furthermore, the above corrected soil resistivity formula is:

[0034] F=ω′1F1+ω′2F2+ω′3F3

[0035] Wherein, F represents the modified soil resistivity formula, ω′1 represents the first weight, ω′2 represents the second weight, ω′3 represents the third weight, F1 represents the first resistivity formula, F2 represents the second resistivity formula, and F3 represents the third resistivity formula.

[0036] Based on the above method embodiment, the present invention provides a corresponding device embodiment;

[0037] The present invention provides a soil resistivity correction device, comprising:

[0038] Data acquisition module, resistivity formula building module, modified soil resistivity formula calculation module and soil resistivity calculation module;

[0039] The above-mentioned data acquisition module is used to obtain the preset logging current, first electrode voltage and preset first electrode distance of the logging method in the test area, the contact area, thickness, preset electrode plate voltage and sampling current of the sampling method, and several preset second electrode distances, preset quadrupole current and second electrode voltage of the quadrupole method; wherein, drilling down to the test area to a preset depth, obtaining several portions of rock from the surface to the preset depth at a preset spacing, obtaining the thickness of each portion of rock, placing conductive electrode plates on both sides of each portion of rock in contact, obtaining the contact area between the conductive electrode plates and the rock, and passing the preset electrode plate voltage to measure the sampling current of the rock at each depth; dividing the conductive electrode plates on both sides of the drilling well into the rock sample, and measuring the rock sample current at each depth. A first grounding electrode, a second grounding electrode and a power supply are arranged separately, one end of the power supply is connected to the first grounding electrode, the other end of the power supply is connected to a power supply electrode extending into the wellbore to a preset depth, and the second grounding electrode is connected to a receiving electrode extending into the wellbore and having a preset first pole distance from the power supply electrode; a preset logging current is passed through the power supply electrode to measure the first electrode voltage at each depth between the receiving electrode and the second grounding electrode; a first current electrode, a first voltage electrode, a second voltage electrode and a second current electrode are arranged in sequence along a straight line in the above-mentioned test area according to a preset second pole distance, a preset quadrupole current is passed through the first current electrode, and a second electrode voltage corresponding to each preset second pole distance is obtained;

[0040] The resistivity formula construction module is used to construct the first resistivity formula, the second resistivity formula and the third resistivity formula according to the preset logging current, the first electrode voltage, the preset first electrode distance, the contact area, the thickness, the preset electrode plate voltage, the sampling current, the preset second electrode distance, the preset quadrupole current and the second electrode voltage;

[0041] The above-mentioned modified soil resistivity formula calculation module is used to calculate the modified soil resistivity formula according to the first weight, the second weight, the third weight, the above-mentioned first resistivity formula, the second resistivity formula and the third resistivity formula; wherein, an importance scale significance table is obtained, a judgment matrix is ​​constructed according to the above-mentioned importance scale significance table, and the maximum eigenvalue of the above-mentioned judgment matrix and the eigenvector corresponding to the above-mentioned maximum eigenvalue are calculated according to the above-mentioned judgment matrix; the above-mentioned eigenvector is normalized to obtain the above-mentioned first weight, the second weight and the third weight;

[0042] The soil resistivity calculation module is used to obtain the depth to be measured in the area to be measured, and calculate the corrected soil resistivity at the depth to be measured according to the depth to be measured and the soil resistivity formula.

[0043] Based on the above method embodiment, the present invention provides a terminal device embodiment;

[0044] The present invention provides a terminal device, comprising a processor, a memory, and a computer program stored in the memory and configured to be executed by the processor. When the processor executes the computer program, a soil resistivity correction method according to any embodiment of the present invention is implemented.

[0045] Based on the above method embodiment, the present invention provides a storage medium embodiment;

[0046] The present invention provides a storage medium, comprising a processor, a memory, and a computer program stored in the memory and configured to be executed by the processor. When the processor executes the computer program, a soil resistivity correction method according to any embodiment of the present invention is implemented.

[0047] The embodiments of the present invention have the following beneficial effects:

[0048] The present invention provides a method, device, terminal equipment and storage medium for correcting soil resistivity. The above method first obtains the preset logging current, first electrode voltage and preset first pole distance of the logging method in the test area, the contact area, thickness, preset pole plate voltage and sampling current of the sampling method, and several preset second pole distances, preset quadrupole current and second electrode voltage of the quadrupole method; wherein, drilling down to a preset depth in the test area, obtaining several portions of rock from the surface to the preset depth at preset intervals, obtaining the thickness of each portion of rock, placing conductive plates on both sides of each portion of rock in contact, obtaining the contact area between the conductive plates and the rock, and passing the preset pole plates. After the voltage is measured, the sampling current of the rock at each depth is obtained; a first grounding electrode, a second grounding electrode and a power supply are arranged on both sides of the well respectively, one end of the power supply is connected to the first grounding electrode, the other end of the power supply is connected to the power supply electrode extending into the well to a preset depth, and the second grounding electrode is connected to a receiving electrode extending into the well and at a preset first pole distance from the power supply electrode; a preset logging current is passed through the power supply electrode to measure the first electrode voltage at each depth between the receiving electrode and the second grounding electrode; the first current is arranged in sequence along a straight line in the above-mentioned test area according to the preset second pole distance A first electrode, a first voltage electrode, a second voltage electrode and a second current electrode are provided, a preset quadrupole current is passed into the first current electrode to obtain the second electrode voltage corresponding to each preset second electrode pitch; then, according to the preset logging current, the first electrode voltage, the preset first electrode pitch, the contact area, the thickness, the preset electrode plate voltage, the sampling current, the preset second electrode pitch, the preset quadrupole current and the second electrode voltage, a first resistivity formula, a second resistivity formula and a third resistivity formula are constructed; then, according to the first weight, the second weight, the third weight, the first resistivity formula, the second resistivity formula and the third resistivity formula, a modified soil resistivity formula is calculated; wherein, an importance scale significance table is obtained, a judgment matrix is ​​constructed according to the importance scale significance table, and the maximum eigenvalue of the judgment matrix and the eigenvector corresponding to the maximum eigenvalue are calculated according to the judgment matrix; the eigenvector is normalized to obtain the first weight, the second weight and the third weight; finally, the depth to be measured in the area to be measured is obtained, and according to the depth to be measured and the soil resistivity formula, the modified soil resistivity at the depth to be measured is calculated. Therefore, the present invention constructs a judgment matrix through an importance scale significance table, and obtains the first weight, the second weight and the third weight corresponding to the well logging method, the sampling method and the quadrupole method through the judgment matrix. Through different weights, the soil resistivity formulas obtained by the well logging method, the sampling method and the quadrupole method are comprehensively calculated, and different weights are assigned to the resistivity formulas obtained by the three methods according to the degree of error, so as to realize the correction of soil resistivity and effectively reduce the measurement errors caused by the single well logging method, the single sampling method and the single quadrupole method. BRIEF DESCRIPTION OF THE DRAWINGS

[0049] Figure 1The present invention is a flow chart of a method for correcting soil resistivity provided by an embodiment of the present invention.

[0050] Figure 2 It is a schematic diagram of measuring soil resistivity using a well logging method provided by an embodiment of the present invention.

[0051] Figure 3 It is a schematic diagram of a first resistivity curve provided by an embodiment of the present invention.

[0052] Figure 4 It is a schematic diagram of a second resistivity curve provided by an embodiment of the present invention.

[0053] Figure 5 It is a schematic diagram of a corrected soil resistivity curve provided by an embodiment of the present invention.

[0054] Figure 6 The figure is a schematic diagram of the structure of a soil resistivity correction device provided by one embodiment of the present invention. DETAILED DESCRIPTION

[0055] The technical solution of the present invention will be described clearly and completely below in conjunction with the accompanying drawings of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0056] like Figure 1 As shown, a method for correcting soil resistivity provided by an embodiment of the present invention includes:

[0057] Step S101: obtaining the preset logging current, first electrode voltage and preset first electrode distance of the logging method in the test area, the contact area, thickness, preset electrode plate voltage and sampling current of the sampling method, and several preset second electrode distances, preset quadrupole current and second electrode voltage of the quadrupole method; wherein, drilling down to a preset depth in the test area, obtaining several portions of rock from the surface to a preset depth at a preset spacing, obtaining the thickness of each portion of rock, placing conductive electrode plates on both sides of each portion of rock to contact, obtaining the contact area between the conductive electrode plates and the rock, and passing the preset electrode plate voltage to measure the sampling current of the rock at each depth; respectively arranging conductive electrode plates on both sides of the wellbore A first grounding electrode, a second grounding electrode and a power supply are provided, one end of the power supply is connected to the first grounding electrode, the other end of the power supply is connected to a power supply electrode extending into the wellbore to a preset depth, and the second grounding electrode is connected to a receiving electrode extending into the wellbore and having a preset first pole distance from the power supply electrode; a preset logging current is passed through the power supply electrode to measure the first electrode voltage at each depth between the receiving electrode and the second grounding electrode; a first current electrode, a first voltage electrode, a second voltage electrode and a second current electrode are sequentially arranged along a straight line in the above-mentioned test area according to a preset second pole distance, a preset quadrupole current is passed through the first current electrode, and a second electrode voltage corresponding to each preset second pole distance is obtained;

[0058] Schematically, the schematic diagram of measuring soil resistivity by well logging is as follows Figure 2 As shown, the electrode B in the figure is the above-mentioned first grounding electrode, the electrode A is the above-mentioned power electrode, the electrode M is the above-mentioned receiving electrode, the electrode N is the above-mentioned second grounding electrode, and the electrode spacing L between the electrode A and the electrode M is the above-mentioned preset first pole distance. The above-mentioned electrodes A, B, M and N together form a caliper. When measuring, the power electrode A is extended to a preset depth, and the position of the receiving electrode M is at a depth of the first pole distance from the power electrode A. At the same time, the electrode A and the electrode M are pulled upward to the ground, and the preset first pole distance between the electrode A and the electrode M is kept unchanged throughout the whole process. The preset logging current is passed into the whole circuit through the power supply, and during the whole measurement process, this preset logging current remains unchanged, and the first electrode voltage corresponding to each depth between the receiving electrode M and the second grounding electrode N from the preset depth to the ground is measured.

[0059] Specifically, the lateral detection range of the well logging method depends on the above-mentioned first pole distance, the detection radius is twice the first pole distance, and the above-mentioned preset depth is 1000m.

[0060] Preferably, the principle of the well logging method is to measure the resistivity of different bottom layers based on the difference in rock conductivity.

[0061] Specifically, the rock sample is placed in a clamped copper electrode plate. In order to reduce the contact resistance and maintain full contact between the conductive plate and the sample, cotton yarn saturated with copper sulfate solution is closely attached to the inner surface of the copper sheet. At the same time, graphite conductive material is coated on the surface of the rock to ensure full contact with the electrode plate. The two ends of the conductive electrode plate are connected to an AC source, an ammeter and a voltmeter, the AC voltage is changed, and the rock resistance is calculated through the voltage-current change curve, and then the soil resistivity curve at each depth is obtained.

[0062] Preferably, since some sampled rocks are fragile and inconvenient to drill, an AC voltage is applied to both ends of the rock sample, and the sampling current of the rock is measured, and then the soil resistivity at each depth is obtained. The polarization effect is small under AC conditions and can be ignored. In order to make the sample meet the same conditions as the ground such as water content as much as possible, the fresh sample should be processed and its resistivity measured as soon as possible.

[0063] Step S102: constructing a first resistivity formula, a second resistivity formula and a third resistivity formula according to the preset logging current, the first electrode voltage, the preset first electrode distance, the contact area, the thickness, the preset electrode plate voltage, the sampling current, the preset second electrode distance, the preset quadrupole current and the second electrode voltage;

[0064] In a preferred embodiment, the first resistivity formula, the second resistivity formula and the third resistivity formula are constructed according to the preset logging current, the first electrode voltage, the preset first electrode distance, the contact area, the thickness, the sampling current, the preset electrode plate voltage, the preset second electrode distance, the preset quadrupole current and the second electrode voltage, including:

[0065] Constructing a first resistivity formula according to the preset logging current, the first electrode voltage and the preset first electrode distance;

[0066] Constructing a second resistivity formula according to the contact area, thickness, sampling current and preset plate voltage;

[0067] A third resistivity formula is constructed according to the above-mentioned preset second pole distance, preset quadrupole current and second electrode voltage.

[0068] In this preferred embodiment, the first resistivity formula of the logging method, the second resistivity formula of the sampling method and the third resistivity formula of the quadrupole method are constructed based on the preset logging current, the first electrode voltage, the preset first electrode distance, the contact area, the thickness, the sampling current, the preset plate voltage, the preset second electrode distance, the preset quadrupole current and the second electrode voltage.

[0069] In another preferred embodiment, the first resistivity formula is constructed according to the preset logging current, the first electrode voltage and the preset first electrode distance, including:

[0070] Calculating the first resistivity at each depth according to the preset logging current, the first electrode voltages and the preset first electrode distance;

[0071] A first resistivity formula is constructed according to the first resistivity and the depth corresponding to the first resistivity.

[0072] Specifically, the first resistivity is calculated according to the following formula:

[0073]

[0074] In the formula, R a represents the first resistivity, L represents the first pole distance, I1 represents the preset logging current, ΔU MN represents the first electrode voltage.

[0075] In this preferred embodiment, the first resistivity at each depth is calculated by presetting the logging current, the first electrode voltage and the first electrode distance, and the first resistivity formula is constructed based on the depth and the first resistivity.

[0076] In another preferred embodiment, a drilling test is conducted in a certain place in Guangdong city, and the logging results are obtained. The first pole distance L is 0.1m, and the soil resistivity within a radius of 0.2m around the well wall is measured. The schematic diagram of the measured first resistivity curve is as follows: Figure 3 As shown in the figure, the vertical coordinate "apparent resistivity" is the first resistivity mentioned above. According to the division principle that the stratification point of the first resistivity curve is the inflection point of the abnormal root of the curve, the test result data is divided by the weighted average method. The division results are shown in Figure 3 As shown by the continuous curve in . From the division results, it can be seen that there is a relatively obvious low resistivity layer above 400m in this well, the overall soil resistivity is relatively even, and the underground soil resistivity distribution difference is not large.

[0077] Preferably, when using the well logging method, due to the different ranges of variation of the physical properties of different rocks, the same rock may present different physical properties or different rocks may present similar physical properties. The same rock layer may also have different resistivity values ​​due to various factors, so the abnormal root inflection point of the soil resistivity curve is used as the stratification point.

[0078] In this preferred embodiment, soil resistivity is measured on-site using a well logging method to obtain a first resistivity curve.

[0079] In another preferred embodiment, the second resistivity formula is constructed based on the contact area, thickness, sampling current and preset plate voltage, including:

[0080] The second resistivity at each depth is calculated based on the contact area, thickness, sampling current and preset plate voltage;

[0081] A second resistivity formula is constructed according to the second resistivity and the depth corresponding to the second resistivity.

[0082] Specifically, the second resistivity is calculated according to the following formula:

[0083]

[0084] Wherein, ρ represents the second resistivity, S represents the contact area, L represents the thickness, U represents the preset plate voltage, and I2 represents the sampling current.

[0085] In this preferred embodiment, the second resistivity at each depth is calculated by using the contact area, thickness, sampling current and preset plate voltage, and a second resistivity formula is constructed based on the depth and the second resistivity.

[0086] In another preferred embodiment, when the drilling rig is drilling in the early stage of logging, the underground geology from the surface to 1000m underground in the well is extracted respectively, and three identical samples of each rock are used for parallel measurement, and the average value of multiple measurements is used as the final resistivity calculation value. At different depths, the second resistivity curve obtained by the test is as follows: Figure 4 As shown in the figure, the vertical axis "soil resistivity" is the second resistivity mentioned above. Figure 4 It can be seen that sampling started from a depth of 100 m. Due to limited sampling, the sample resistivity measurement results are not as continuous as the logging results, but the numerical range is relatively consistent with the logging results.

[0087] In this preferred embodiment, soil resistivity is measured on-site using a sampling method to obtain a second resistivity curve.

[0088] In another preferred embodiment, the third resistivity formula is constructed according to the preset second pole distance, the preset quadrupole current and the second electrode voltage, including:

[0089] According to each of the above-mentioned preset second pole distances, the preset quadrupole current and the second electrode voltage, a third resistivity corresponding to each of the above-mentioned preset second pole distances is calculated;

[0090] The third resistivity, the preset second pole distance corresponding to the third resistivity, the preset quadrupole current and the second electrode voltage are inverted to obtain the third resistivity at each depth, and then the third resistivity formula is obtained.

[0091] Specifically, the third resistivity is calculated according to the following formula:

[0092]

[0093] Where ρ1 represents the third resistivity, a represents the preset second pole distance, I3 represents the preset quadrupole current, and U CD represents the second electrode voltage.

[0094] Specifically, the calculation formula of the third resistivity is transformed from the following formula:

[0095]

[0096] In the formula, a1 represents the distance between the first current electrode and the first voltage electrode, a2 represents the distance between the first current electrode and the second voltage electrode, a3 represents the distance between the first voltage electrode and the second current electrode, and a4 represents the distance between the second voltage electrode and the second current electrode.

[0097] Specifically, the values ​​of a1, a2, a3 and a4 are all set to a, and the above formula can be converted into a formula for calculating the third resistivity.

[0098] Specifically, the third resistivity formula obtained by this method has a depth range of 0 to 100 m.

[0099] In this preferred embodiment, the third resistivity at different second electrode distances is calculated by presetting the second electrode distance, the preset quadrupole current and the second electrode voltage, and then the third resistivity, the preset second electrode distance, the preset quadrupole current and the second electrode voltage corresponding to the third resistivity are inverted to obtain the third resistivity at each depth, and then the third resistivity formula is obtained.

[0100] Step S103: Calculate a modified soil resistivity formula according to the first weight, the second weight, the third weight, the first resistivity formula, the second resistivity formula and the third resistivity formula; wherein, obtain an importance scale significance table, construct a judgment matrix according to the importance scale significance table, and calculate the maximum eigenvalue of the judgment matrix and the eigenvector corresponding to the maximum eigenvalue according to the judgment matrix; normalize the eigenvector to obtain the first weight, the second weight and the third weight;

[0101] Specifically, the significance table of the above importance scale is as follows:

[0102]

[0103]

[0104] Indicatively, the well logging method is the most important because it can fully reflect the actual soil resistivity in a small area of ​​the region and is not affected by the adjacent ground conductors. The measurement results of the quadrupole method are considered slightly more important because they will be affected by the ground conductors. The sampling method is separated from the original soil environment during the test, so its importance is considered slightly lower. Therefore, according to the above importance scale significance table, the importance judgment table is constructed as follows:

[0105] index Well logging Sampling method Quadrupole method Well logging 1 3 2 Sampling method 1 / 3 1 1 / 3 Quadrupole method 1 / 2 3 1

[0106] According to the above importance judgment table, the judgment matrix A is obtained as follows:

[0107]

[0108] In a preferred embodiment, the maximum eigenvalue of the judgment matrix and the eigenvector corresponding to the maximum eigenvalue are calculated according to the judgment matrix, including:

[0109] Normalizing all elements of the above judgment matrix by columns to obtain a normalized first judgment matrix;

[0110] Calculate the sum of the elements in each row of the first judgment matrix, and use the sum as the element of the row where each sum in the first judgment matrix is ​​located, to obtain a second judgment matrix;

[0111] According to the second judgment matrix and the judgment matrix, the maximum eigenvalue and the eigenvector are calculated;

[0112] Among them, each element of the first judgment matrix is ​​calculated according to the following formula:

[0113]

[0114] In the formula, represents the i-th row and j-th column element in the first judgment matrix above, a ij represents the i-th row and j-th column element in the above judgment matrix, a kj represents the kth element in the jth column to be normalized in the above judgment matrix;

[0115] The above maximum eigenvalue is calculated according to the following formula:

[0116]

[0117] In the formula, λ max represents the maximum eigenvalue, A represents the above judgment matrix, represents the element of the i-th row of the second judgment matrix, ω represents the eigenvector, n represents the matrix order, (Aω) i Represents the product of the i-th judgment matrix and the eigenvector.

[0118] Specifically, the elements of each row of the second judgment matrix are calculated according to the following formula:

[0119]

[0120] Specifically, after obtaining the maximum eigenvalue, the maximum eigenvalue has the following relationship with the order of the matrix:

[0121]

[0122] In the formula, λ i represents the i-th eigenvalue.

[0123] Therefore, the first index value for judging the consistency of the above judgment matrix can be calculated according to the following formula:

[0124]

[0125] Wherein, CI represents the first index value.

[0126] According to the preset average random consistency index table, the random consistency index value of the above judgment matrix is ​​obtained. The above preset average random consistency index table is shown in the following table:

[0127] Matrix order 3 4 5 6 7 8 9 RI value 0.59 0.90 1.12 1.24 1.31 1.41 1.45

[0128] Since the constructed judgment matrix in this embodiment is a 3rd-order matrix, the random consistency index RI value of the judgment matrix is ​​0.59.

[0129] Specifically, the consistency ratio of the above judgment matrix is ​​calculated according to the following formula:

[0130]

[0131] Specifically, the consistency ratio of the judgment matrix is ​​0.05. When CR < 0.1, it can be considered that the consistency of the constructed judgment matrix meets the requirements. Therefore, the judgment matrix constructed in this step is reasonable, and the eigenvector corresponding to its maximum eigenvalue can be normalized to obtain each weight. If the consistency ratio calculated at the end is not less than 0.1, it is necessary to re-take values ​​from the importance scale significance table, construct an importance judgment table, and then re-process and calculate the newly constructed judgment matrix accordingly.

[0132] Specifically, after normalizing the feature vector, the weight values ​​are shown in the following table:

[0133]

[0134] That is, ω′1 is 0.524, ω′2 is 0.142, and ω′3 is 0.334.

[0135] In this preferred embodiment, the maximum eigenvalue of the judgment matrix and the eigenvector corresponding to the maximum eigenvalue are obtained.

[0136] In another preferred embodiment, the above-mentioned corrected soil resistivity formula is:

[0137] F=ω′1F1+ω′2F2+ω′3F3

[0138] Wherein, F represents the modified soil resistivity formula, ω′1 represents the first weight, ω′2 represents the second weight, ω′3 represents the third weight, F1 represents the first resistivity formula, F2 represents the second resistivity formula, and F3 represents the third resistivity formula.

[0139] Schematically, the corrected soil resistivity curve is as follows Figure 5 As shown, Figure 5 The continuous curve corresponding to the "joint modeling" in is the curve corresponding to the above-mentioned modified soil resistivity formula. Since no sampling was performed at the depth of 0-100m during sampling, Figure 5 There is no corresponding curve for the sampling method with a depth less than 100.

[0140] In this preferred embodiment, the final corrected soil resistivity formula is obtained by adding the first weight to the first resistivity formula, the second weight to the second resistivity formula, and the third weight to the third resistivity. This formula uses depth as the independent variable and the corrected soil resistivity as the dependent variable.

[0141] Step S104: obtaining the depth to be measured in the area to be measured, and calculating the corrected soil resistivity at the depth to be measured according to the depth to be measured and the soil resistivity formula.

[0142] Specifically, since the calculation depth range of the third resistivity formula obtained by the quadrupole method is 0 to 100 m, when the soil resistivity at a depth greater than 100 m needs to be obtained, the value of ω′3F3 in the soil resistivity formula F is 0.

[0143] Preferably, by measuring and correcting the soil resistivity, the resistance characteristics of the soil in the test area can be understood, providing a basis for the design and operation of the grounding device.

[0144] In this step, by substituting the depth to be measured into the corrected soil resistivity formula, the corrected soil resistivity value at the depth to be measured can be calculated.

[0145] Based on the above method embodiment, the present invention provides a corresponding device embodiment.

[0146] like Figure 6 As shown, an embodiment of the present invention provides a soil resistivity correction device, comprising:

[0147] Data acquisition module, resistivity formula building module, modified soil resistivity formula calculation module and soil resistivity calculation module;

[0148] The above-mentioned data acquisition module is used to obtain the preset logging current, first electrode voltage and preset first electrode distance of the logging method in the test area, the contact area, thickness, preset electrode plate voltage and sampling current of the sampling method, and several preset second electrode distances, preset quadrupole current and second electrode voltage of the quadrupole method; wherein, drilling down to the test area to a preset depth, obtaining several portions of rock from the surface to the preset depth at a preset spacing, obtaining the thickness of each portion of rock, placing conductive electrode plates on both sides of each portion of rock in contact, obtaining the contact area between the conductive electrode plates and the rock, and passing the preset electrode plate voltage to measure the sampling current of the rock at each depth; dividing the conductive electrode plates on both sides of the drilling well into the rock sample, and measuring the rock sample current at each depth. A first grounding electrode, a second grounding electrode and a power supply are arranged separately, one end of the power supply is connected to the first grounding electrode, the other end of the power supply is connected to a power supply electrode extending into the wellbore to a preset depth, and the second grounding electrode is connected to a receiving electrode extending into the wellbore and having a preset first pole distance from the power supply electrode; a preset logging current is passed through the power supply electrode to measure the first electrode voltage at each depth between the receiving electrode and the second grounding electrode; a first current electrode, a first voltage electrode, a second voltage electrode and a second current electrode are arranged in sequence along a straight line in the above-mentioned test area according to a preset second pole distance, a preset quadrupole current is passed through the first current electrode, and a second electrode voltage corresponding to each preset second pole distance is obtained;

[0149] The resistivity formula construction module is used to construct the first resistivity formula, the second resistivity formula and the third resistivity formula according to the preset logging current, the first electrode voltage, the preset first electrode distance, the contact area, the thickness, the preset electrode plate voltage, the sampling current, the preset second electrode distance, the preset quadrupole current and the second electrode voltage;

[0150] The above-mentioned modified soil resistivity formula calculation module is used to calculate the modified soil resistivity formula according to the first weight, the second weight, the third weight, the above-mentioned first resistivity formula, the second resistivity formula and the third resistivity formula; wherein, an importance scale significance table is obtained, a judgment matrix is ​​constructed according to the above-mentioned importance scale significance table, and the maximum eigenvalue of the above-mentioned judgment matrix and the eigenvector corresponding to the above-mentioned maximum eigenvalue are calculated according to the above-mentioned judgment matrix; the above-mentioned eigenvector is normalized to obtain the above-mentioned first weight, the second weight and the third weight;

[0151] The soil resistivity calculation module is used to obtain the depth to be measured in the area to be measured, and calculate the corrected soil resistivity at the depth to be measured according to the depth to be measured and the soil resistivity formula.

[0152] It should be noted that the device embodiments described above are merely schematic, wherein the modules described above as separate components may or may not be physically separated, and the components displayed as modules may or may not be physical modules, that is, they may be located in one place, or they may be distributed on multiple network units. Some or all of the modules may be selected according to actual needs to achieve the purpose of the present embodiment. In addition, in the accompanying drawings of the device embodiments provided by the present invention, the connection relationship between the modules indicates that there is a communication connection between them, which may be specifically implemented as one or more communication buses or signal lines. A person of ordinary skill in the art may understand and implement it without creative work. The above schematic diagram is merely an example of a soil resistivity correction device, and does not constitute a limitation on a soil resistivity correction device, and may include more or fewer components than shown in the figure, or a combination of certain components, or different components.

[0153] Based on the above method item embodiments, the present invention provides corresponding terminal device item embodiments.

[0154] Another embodiment of the present invention provides a terminal device, including a processor, a memory, and a computer program stored in the memory and configured to be executed by the processor, and when the processor executes the computer program, a soil resistivity correction method according to any one of the embodiments of the present invention is implemented.

[0155] Exemplarily, in this embodiment, the computer program may be divided into one or more modules, which are stored in the memory and executed by the processor to implement the present invention. The one or more module elements may be a series of computer program instruction segments capable of implementing specific functions, which are used to describe the execution process of the computer program in the device;

[0156] The terminal device may be a computing device such as a desktop computer, a notebook, a PDA, a cloud server, etc. The device may include, but is not limited to, a processor, a memory;

[0157] The processor referred to herein may be a central processing unit (CPU), other general-purpose processors, digital signal processors (DSP), application-specific integrated circuits (ASIC), field-programmable gate arrays (FPGA) or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, etc. The general-purpose processor may be a microprocessor or any conventional processor, etc. The above-mentioned processor is the control center of the above-mentioned device, and uses various interfaces and lines to connect various parts of the entire device;

[0158] The above-mentioned memory can be used to store the above-mentioned computer programs and / or modules. The above-mentioned processor realizes various functions of the above-mentioned device by running or executing the computer programs and / or modules stored in the above-mentioned memory, and calling the data stored in the memory. The above-mentioned memory can mainly include a program storage area and a data storage area, wherein the program storage area can store an operating system, at least one application required for a function, etc.; in addition, the memory can include a high-speed random access memory, and can also include a non-volatile memory, such as a hard disk, a memory, a plug-in hard disk, a smart memory card (Smart Media Card, SMC), a secure digital (Secure Digital, SD) card, a flash card (Flash Card), at least one disk storage device, a flash memory device, or other volatile solid-state storage devices.

[0159] Based on the above method item embodiments, the present invention provides a corresponding storage medium item embodiment.

[0160] Another embodiment of the present invention provides a storage medium, wherein the storage medium includes a stored computer program, wherein when the computer program is running, the device where the storage medium is located is controlled to execute the soil resistivity correction method described in any embodiment of the present invention.

[0161] In this embodiment, the storage medium is a computer-readable storage medium, the computer program includes computer program code, and the computer program code may be in source code form, object code form, executable file or some intermediate form, etc. The computer-readable medium may include: any entity or device capable of carrying the computer program code, recording medium, USB flash drive, mobile hard disk, magnetic disk, optical disk, computer memory, read-only memory (ROM), random access memory (RAM), electric carrier signal, telecommunication signal and software distribution medium, etc.

[0162] Compared with the prior art, by implementing the above-mentioned embodiments of the present invention, the measurement error of soil resistivity caused by a separate well logging method, a separate sampling method and a separate quadrupole method can be reduced.

[0163] The above is a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principle of the present invention. These improvements and modifications are also considered to be within the scope of protection of the present invention.

Claims

1. A method for correcting soil resistivity, characterized in that: include: The preset logging current, first electrode voltage and preset first electrode distance of the logging method in the test area, the contact area, thickness, preset electrode plate voltage and sampling current of the sampling method, and several preset second electrode distances, preset quadrupole current and second electrode voltage of the quadrupole method are obtained; wherein, the well is drilled down to a preset depth in the test area, and several portions of rock from the surface to the preset depth are obtained at preset intervals to obtain the thickness of each portion of rock, and conductive electrode plates are placed on both sides of each portion of rock to contact with each other to obtain the contact area between the conductive electrode plate and the rock, and the sampling current of the rock at each depth is measured after the preset electrode plate voltage is passed; the first A grounding electrode, a second grounding electrode and a power supply, wherein one end of the power supply is connected to the first grounding electrode, the other end of the power supply is connected to a power supply electrode extending into the wellbore to a preset depth, and the second grounding electrode is connected to a receiving electrode extending into the wellbore and having a preset first pole distance from the power supply electrode; a preset logging current is passed through the power supply electrode to measure the first electrode voltage at each depth between the receiving electrode and the second grounding electrode; a first current electrode, a first voltage electrode, a second voltage electrode and a second current electrode are sequentially arranged along a straight line in the measured area according to a preset second pole distance, a preset quadrupole current is passed through the first current electrode, and a second electrode voltage corresponding to each preset second pole distance is obtained; Constructing a first resistivity formula, a second resistivity formula and a third resistivity formula according to the preset logging current, the first electrode voltage, the preset first electrode distance, the contact area, the thickness, the preset electrode plate voltage, the sampling current, the preset second electrode distance, the preset quadrupole current and the second electrode voltage; According to the first weight, the second weight, the third weight, the first resistivity formula, the second resistivity formula and the third resistivity formula, a corrected soil resistivity formula is calculated; wherein, an importance scale significance table is obtained, a judgment matrix is ​​constructed according to the importance scale significance table, and the maximum eigenvalue of the judgment matrix and the eigenvector corresponding to the maximum eigenvalue are calculated according to the judgment matrix; the eigenvector is normalized to obtain the first weight, the second weight and the third weight; The depth to be measured in the measured area is obtained, and the corrected soil resistivity at the depth to be measured is calculated according to the depth to be measured and the soil resistivity formula.

2. A method for correcting soil resistivity according to claim 1, characterized in that: The method of constructing a first resistivity formula, a second resistivity formula and a third resistivity formula according to the preset logging current, the first electrode voltage, the preset first electrode distance, the contact area, the thickness, the sampling current, the preset electrode plate voltage, the preset second electrode distance, the preset quadrupole current and the second electrode voltage comprises: Constructing a first resistivity formula according to the preset logging current, the first electrode voltage and the preset first electrode distance; constructing a second resistivity formula according to the contact area, thickness, sampling current and preset plate voltage; A third resistivity formula is constructed according to the preset second pole distance, the preset quadrupole current and the second electrode voltage.

3. A method for correcting soil resistivity according to claim 2, characterized in that: The step of constructing a first resistivity formula according to the preset logging current, the first electrode voltage and the preset first electrode distance comprises: Calculating a first resistivity at each depth according to the preset logging current, each of the first electrode voltages and a preset first electrode distance; A first resistivity formula is constructed according to the first resistivity and the depth corresponding to the first resistivity.

4. A method for correcting soil resistivity according to claim 3, characterized in that: The second resistivity formula is constructed according to the contact area, thickness, sampling current and preset plate voltage, including: Calculating the second resistivity at each depth according to the contact area, thickness, sampling current and preset plate voltage; A second resistivity equation is constructed according to the second resistivity and the depth corresponding to the second resistivity.

5. A method for correcting soil resistivity according to claim 4, characterized in that: The method of constructing a third resistivity formula according to the preset second pole distance, the preset quadrupole current and the second electrode voltage includes: According to each of the preset second pole distances, the preset quadrupole current and the second electrode voltage, a third resistivity corresponding to each of the preset second pole distances is calculated; The third resistivity, the preset second electrode distance corresponding to the third resistivity, the preset quadrupole current and the second electrode voltage are inverted to obtain the third resistivity at each depth, and then the third resistivity formula is obtained.

6. A method for correcting soil resistivity according to claim 5, characterized in that: The step of calculating the maximum eigenvalue and the eigenvector corresponding to the maximum eigenvalue according to the judgment matrix includes: Normalizing all elements of the judgment matrix by column to obtain a normalized first judgment matrix; Calculate the sum of the elements in each row of the first judgment matrix, and use the sum as the element of the row where each sum in the first judgment matrix is ​​located, to obtain a second judgment matrix; According to the second judgment matrix and the judgment matrix, the maximum eigenvalue and the eigenvector are calculated; The elements of the first judgment matrix are calculated according to the following formula: In the formula, represents the i-th row and j-th column element in the first judgment matrix, a ij represents the i-th row and j-th column element in the judgment matrix, a kj represents the kth element in the jth column to be normalized in the judgment matrix; The maximum eigenvalue is calculated according to the following formula: In the formula, λ max represents the maximum eigenvalue, A represents the judgment matrix, represents the element of the i-th row of the second judgment matrix, ω represents the eigenvector, n represents the n-th row, (Aω) i Represents the i-th component of the product of the i-th judgment matrix and the eigenvector.

7. A method for correcting soil resistivity according to claim 6, characterized in that: The corrected soil resistivity formula is: F=ω′1F1+ω′2F2+ω′3F3 Wherein, F represents the modified soil resistivity formula, ω′1 represents the first weight, ω′2 represents the second weight, ω′3 represents the third weight, F1 represents the first resistivity formula, F2 represents the second resistivity formula, and F3 represents the third resistivity formula.

8. A soil resistivity correction device, characterized in that: include: Data acquisition module, resistivity formula building module, modified soil resistivity formula calculation module and soil resistivity calculation module; The data acquisition module is used to obtain the preset logging current, first electrode voltage and preset first electrode distance of the logging method in the test area, the contact area, thickness, preset electrode plate voltage and sampling current of the sampling method, and several preset second electrode distances, preset quadrupole current and second electrode voltage of the quadrupole method; wherein, drilling down to the test area to a preset depth, obtaining several portions of rock from the surface to the preset depth at a preset spacing, obtaining the thickness of each portion of rock, placing conductive electrode plates on both sides of each portion of rock to contact, obtaining the contact area between the conductive electrode plates and the rock, and passing the preset electrode plate voltage to measure the sampling current of the rock at each depth; dividing the conductive electrode plates on both sides of the drilling well into the rock sample, and measuring the rock sample, and measuring the rock sample. A first grounding electrode, a second grounding electrode and a power supply are arranged separately, one end of the power supply is connected to the first grounding electrode, the other end of the power supply is connected to a power supply electrode extending into the wellbore to a preset depth, and the second grounding electrode is connected to a receiving electrode extending into the wellbore and having a preset first pole distance from the power supply electrode; a preset logging current is passed through the power supply electrode to measure the first electrode voltage at each depth between the receiving electrode and the second grounding electrode; a first current electrode, a first voltage electrode, a second voltage electrode and a second current electrode are arranged in sequence along a straight line in the measured area according to a preset second pole distance, a preset quadrupole current is passed through the first current electrode, and a second electrode voltage corresponding to each preset second pole distance is obtained; The resistivity formula construction module is used to construct the first resistivity formula, the second resistivity formula and the third resistivity formula according to the preset logging current, the first electrode voltage, the preset first electrode distance, the contact area, the thickness, the preset electrode plate voltage, the sampling current, the preset second electrode distance, the preset quadrupole current and the second electrode voltage; The modified soil resistivity formula calculation module is used to calculate the modified soil resistivity formula according to the first weight, the second weight, the third weight, the first resistivity formula, the second resistivity formula and the third resistivity formula; wherein, an importance scale significance table is obtained, a judgment matrix is ​​constructed according to the importance scale significance table, and the maximum eigenvalue of the judgment matrix and the eigenvector corresponding to the maximum eigenvalue are calculated according to the judgment matrix; the eigenvector is normalized to obtain the first weight, the second weight and the third weight; The soil resistivity calculation module is used to obtain the depth to be measured in the area to be measured, and calculate the corrected soil resistivity at the depth to be measured according to the depth to be measured and the soil resistivity formula.

9. A terminal device, characterized in that: The invention comprises a processor, a memory and a computer program stored in the memory and configured to be executed by the processor, wherein when the processor executes the computer program, a method for correcting soil resistivity as claimed in any one of claims 1 to 7 is implemented.

10. A storage medium, characterized in that: The storage medium includes a stored computer program, wherein when the computer program is executed, the device where the storage medium is located is controlled to execute a soil resistivity correction method as claimed in any one of claims 1 to 7.

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