Network parallel electrical method detection method capable of eliminating influence of electrode polarization effect

Abstract

The invention discloses a network parallel electrical method detection method capable of eliminating the influence of an electrode polarization effect, and a laid electrical method detection system only needs to be additionally provided with a polarization measurement electrode P for polarization measurement compared with an existing network parallel electrical method detection system. When electrical detection is carried out, reference measurement is firstly carried out to obtain a reference potential difference of each measuring electrode, then conventional measurement is firstly carried out to obtain a potential difference of each measuring electrode during each detection, and then polarization measurement is carried out to obtain a polarization potential difference of each measuring electrode; subtracting the polarization potential difference of each measuring electrode from the respective corresponding reference potential difference for each detection data to obtain a potential deviation value of each measuring electrode caused by polarization, and finally subtracting the respective corresponding potential deviation value from the potential difference of each measuring electrode during conventional measurement to obtain a potential deviation value of each measuring electrode. According to the mode, the influence of the polarization effect of the electrode on electrical method detection can be effectively eliminated, and the precision of network parallel electrical method detection is ensured.

Description

Technical Field

[0001] The present invention relates to the technical field of electrical prospecting, and in particular to a network parallel electrical prospecting method capable of eliminating the influence of electrode polarization effect. Background Art

[0002] As a commonly used geophysical exploration method, electrical prospecting reflects the resistivity distribution of underground media (such as soil, rock, etc.) by arranging electrodes on the ground surface, applying current and measuring the potential difference. However, in practical applications, polarization effect will occur when the power supply electrode applies current, resulting in the drift of the electrode potential, so that the voltage measured when it is used as a measuring electrode subsequently will deviate. The existing compensation methods usually adopt the dual-mode electrode technology, that is, one set of electrodes is dedicated to power supply and the other set of electrodes is dedicated to measurement. Although it can get rid of the influence of polarization effect, two sets of electrodes need to be arranged, and the equipment cost and construction cost are relatively high.

[0003] In the traditional electrical prospecting process, each arranged electrode is successively used as A, B, M, and N electrodes (A and B electrodes supply power, and M and N electrodes measure). In addition, currently, industry scholars have proposed network parallel electrical prospecting, which arranges a reference electrode N. During the measurement process, the potential values of each electrode are measured separately from this reference electrode, and then the potential difference of each electrode is obtained by subtracting the potential of the reference electrode from the potential of different electrodes; finally, different electrodes are subtracted from each other to calculate the potential difference between each electrode. This method can effectively accelerate the measurement speed of electrical prospecting. However, both the traditional electrical prospecting method and the parallel electrical prospecting method face the problem that the data collected after measurement is distorted due to the polarization of the electrode power supply.

[0004] Therefore, how to provide a new electrical prospecting method that can effectively eliminate the influence of electrode polarization effect on electrical prospecting and ensure the accuracy of network parallel electrical prospecting on the premise of relatively low construction cost is the research direction required by the present invention. Summary of the Invention

[0005] Aiming at the problems existing in the above-mentioned prior art, the present invention provides a network parallel electrical prospecting method capable of eliminating the influence of electrode polarization effect, which can effectively eliminate the influence of electrode polarization effect on electrical prospecting and ensure the accuracy of network parallel electrical prospecting on the premise of relatively low construction cost.

[0006] In order to achieve the above object, the technical solution adopted by the present invention is: a network parallel electrical prospecting method capable of eliminating the influence of electrode polarization effect, and the specific steps are as follows:

[0007] Step 1. Deployment of the electrical prospecting system: C measuring electrodes are deployed in the area to be detected in accordance with the network parallel electrical method. At the same time, a reference electrode N and an infinite far electrode B are deployed. Then, a polarization measuring electrode P is deployed near each measuring electrode for polarization measurement. The polarization measuring electrode P is deployed at a position relatively close to each measuring electrode, such as the center of the survey line formed by each measuring electrode, which can further ensure the subsequent calibration accuracy.

[0008] Step 2. Benchmark measurement: First, power is supplied to the polarization measuring electrode P and the infinite far electrode B, and the relative potentials of all measuring electrodes and the reference electrode N are measured, and the potential differences U between each measuring electrode and the reference electrode N are recorded. Pbase,i , i = 1, 2, 3,..., C;

[0009] Step 3. Conventional measurement: The electrical prospecting area is subjected to an electrical prospecting using the network parallel electrical method to obtain the potential differences between all measuring electrodes and the reference electrode N, which are recorded as U. i , where i represents the potential difference between the i-th measuring electrode and the reference electrode N;

[0010] Step 4. Polarization measurement: After completing an electrical prospecting, power is supplied to the polarization measuring electrode P and the infinite far electrode B, and under this condition, the potential differences between all measuring electrodes and the reference electrode N are obtained and recorded as U. P,i , where i represents the potential difference between the i-th measuring electrode and the reference electrode N;

[0011] Step 5. Cyclic measurement: Steps 3 and 4 together constitute a complete electrical prospecting process. Subsequently, each time an electrical prospecting is performed on the detection area, Steps 3 and 4 are cycled once until all electrical prospecting processes are completed;

[0012] Step 6. Data correction processing to eliminate the influence of polarization effect: The data obtained from each electrical prospecting is corrected using the reference measurement data in Step 2 to obtain the true potential data after eliminating the polarization effect for each electrical prospecting.

[0013] Step 7. Electrical imaging: The true potential data obtained in Step 6 is used for electrical data processing to obtain the imaging result of the detection area.

[0014] Furthermore, Step 6 is specifically as follows: Select the U of each measuring electrode obtained from polarization measurement in one of the electrical prospecting operations. P,i Respectively subtract the U of each measuring electrode during the reference measurement. Pbase,i And calculate the potential offset ΔU caused by polarization. P,i :

[0015] ΔU P,i = U P,i - U Pbase,i, where \(i = 1, 2, 3, \cdots, C\)

[0016] Subsequently, this potential shift is used to correct the \(U\) of each measurement electrode obtained from the conventional measurement in the same electro - method detection, i to obtain the true potential data \(U\) after eliminating the polarization effect in this time. corr,i ;

[0017] \(U\) corr,i \(=\) \(U\) i \(-\Delta U\) P,i , where \(i = 1, 2, 3, \cdots, C\)

[0018] This step is repeated for each of the remaining times, so as to obtain the true potential data after eliminating the polarization effect for each electro - method detection.

[0019] Compared with the prior art, the present invention has the following advantages:

[0020] 1. The electro - method detection system arranged in the present invention, compared with the detection system of the existing network parallel electro - method, does not require a dual - mode electrode system, and only needs to additionally set up a polarization measurement electrode \(P\) for polarization measurement; this method is not only convenient for layout, but also has a lower construction cost.

[0021] 2. When the present invention conducts electro - method detection, first, a reference measurement is carried out to obtain the reference potential difference of each measurement electrode, then for each detection in the same detection area, a conventional measurement is first carried out to obtain the potential difference of each measurement electrode, and then a polarization measurement is carried out to obtain the polarization potential difference of each measurement electrode; then, for the data of each detection, first, the polarization potential difference of each measurement electrode is subtracted from the reference potential difference of each measurement electrode to obtain the potential shift value caused by polarization for each measurement electrode, and finally, the potential difference of each measurement electrode during the conventional measurement is subtracted from its corresponding potential shift value, so as to obtain the true potential data after eliminating the polarization effect for each electro - method detection. This method can effectively eliminate the influence of the electrode polarization effect on the electro - method detection and ensure the accuracy of the network parallel electro - method detection. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 is the layout schematic diagram of the electro - method detection system in the present invention;

[0023] Figure 2 is the overall flowchart in the present invention;

[0024] Figure 3 is the data correction processing schematic diagram in the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0025] The present invention will be further described below.

[0026] As Figure 2 shown, the specific steps of the present invention are as follows:

[0027] Step 1. Deployment of the electrical method detection system: C measuring electrodes are deployed in the area to be detected in the manner of existing network parallel electrical method. At the same time, a reference electrode N and an infinite far electrode B are deployed. Then, a polarization measurement electrode P is deployed near each measuring electrode for polarization measurement. The polarization measurement electrode P is deployed at a position relatively close to each measuring electrode, such as the center of the survey line formed by each measuring electrode, which can further ensure the subsequent calibration accuracy. In addition, each of the above electrodes is the same existing electrode, which can also ensure the consistency of polarization measurement of different electrodes in the subsequent process.

[0028] Step 2. Reference measurement: First, power is supplied to the polarization measurement electrode P and the infinite far electrode B, and the relative potentials of all measuring electrodes and the reference electrode N are measured, and the potential differences U between each measuring electrode and the reference electrode N are recorded. Pbase,i , i = 1, 2, 3,..., C.

[0029] Step 3. Conventional measurement: The electrical method detection is carried out on the detection area once by using the network parallel electrical method, so as to obtain the potential differences between all measuring electrodes and the reference electrode N respectively, and record them as U i , where i represents the potential difference between the i-th measuring electrode and the reference electrode N.

[0030] Step 4. Polarization measurement: After one electrical method detection is completed, power is supplied to the polarization measurement electrode P and the infinite far electrode B. In this case, the potential differences between all measuring electrodes and the reference electrode N are obtained and recorded as U P,i , where i represents the potential difference between the i-th measuring electrode and the reference electrode N.

[0031] Step 5. Cyclic measurement: Steps 3 and 4 together constitute a complete electrical method detection process. In subsequent electrical method detections of the detection area, steps 3 and 4 are cycled once each time until all electrical method detection processes are completed.

[0032] Step 6. Data calibration processing to eliminate the influence of polarization effect: The data in each electrical method detection is calibrated by using the reference measurement data in step 2, so as to obtain the true potential data after eliminating the polarization effect in each electrical method detection as Figure 3 shown. Specifically: Select the U of each measuring electrode obtained by polarization measurement in one of the electrical method detections P,i and the U of each measuring electrode during the reference measurement respectively Pbase,i to make a difference, and calculate the potential offset ΔU P,i caused by polarization:

[0033] ΔU P,i = U P,i - U Pbase,i , i = 1, 2, 3,..., C

[0034] Subsequently, the obtained U of each measurement electrode in the conventional measurement during the same electrical prospecting is corrected by using this potential offset to obtain the true potential data U after eliminating the polarization effect in this time. i ; corr,i ;

[0035] U corr,i = U i -ΔU P,i , where i = 1, 2, 3,..., C

[0036] This step is repeated for each of the remaining times, so as to obtain the true potential data after eliminating the polarization effect for each electrical prospecting.

[0037] Step Seven, Electrical Imaging: The obtained true potential data in Step Six is used to perform electrical data processing by using the existing method, so as to obtain the imaging result of the detection area.

[0038] The above are only the preferred embodiments of the present invention. It should be noted that: for those of ordinary skill in the art, without departing from the principle of the present invention, several improvements and modifications can be made, and these improvements and modifications should also be regarded as the protection scope of the present invention.

Claims

1. A network parallel electrical method detection method capable of eliminating the influence of electrode polarization effect, characterized in that, The specific steps are as follows: Step 1. Deployment of the electrical prospecting system: C measuring electrodes are deployed in the area to be detected in the manner of network parallel electrical method. At the same time, a reference electrode N and an infinite far electrode B are deployed. Then, a polarization measuring electrode P is deployed near each measuring electrode for polarization measurement; Step 2. Reference measurement: First, power the polarization measurement electrode P and the infinite far electrode B, measure the relative potential of all measurement electrodes and the reference electrode N, and record the potential difference U between each measurement electrode and the reference electrode N Pbase,i , i = 1, 2, 3,..., C; Step 3. Conventional measurement: Perform an electrical method detection on the detection area using network parallel electrical method, so as to obtain the potential difference between each measurement electrode and the reference electrode N, and record it as U i , where \(U_i\) represents the potential difference between the \(i\)-th measurement electrode and the reference electrode N; Step 4. Polarization measurement: After completing one electrical method detection, power is supplied to the polarization measurement electrode P and the infinite far electrode B. In this case, the potential differences between all measurement electrodes and the reference electrode N are obtained and recorded as U P,i , where \(U_i\) represents the potential difference between the \(i\)-th measurement electrode and the reference electrode N; Step 5. Cyclic measurement: Steps 3 and 4 together constitute a complete electrical prospecting process. In subsequent electrical prospecting of the detection area, steps 3 and 4 are cycled each time until all electrical prospecting processes are completed; Step 6. Data correction processing to eliminate the influence of polarization effect: The data in each electrical prospecting is corrected using the reference measurement data in Step 2, so as to obtain the true potential data after eliminating the polarization effect in each electrical prospecting; Step 7. Electrical imaging: The true potential data obtained in Step 6 is used for electrical data processing, so as to obtain the imaging result of the detection area.

2. The network parallel electrical method detection method capable of eliminating the influence of electrode polarization effect according to claim 1, characterized in that, Step six is specifically as follows: Select the U of each measurement electrode obtained from polarization measurement in one of the electrical prospecting operations P,i and separately subtract the U of each measurement electrode during the reference measurement Pbase,i to calculate the potential offset ΔU caused by polarization P,i : ΔU P,i = U P,i - U Pbase,i , i = 1, 2, 3, ..., C Subsequently, this potential offset is used to correct the U of each measurement electrode obtained from the conventional measurement in the same electrophysical prospecting, i so as to obtain the true potential data U after eliminating the polarization effect in this measurement, corr,i ; U corr,i = U i - ΔU P,i , i = 1, 2, 3, ..., C This step is repeated for each of the remaining times, so as to obtain the true potential data after eliminating the polarization effect in each electrical prospecting.

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