A remote monitoring system and method for water and salt migration

Abstract

The present invention relates to a remote monitoring system and method for water and salt migration, the system comprising: a resistivity measuring device, a wireless transmission device, a temperature monitoring device and a data processing and visualization device; the resistivity measuring device is used to measure the apparent resistivity of the underground medium of the site; the temperature monitoring device is used to monitor and record the atmospheric temperature and the underground field temperature in real time, and is also used to fit the underground field temperature; the wireless transmission device is used to transmit the apparent resistivity and the fitted underground field temperature to the data processing and visualization device; the data processing and visualization device is used to invert the apparent resistivity to obtain the inverted resistivity, and use the fitted underground field temperature to correct the inverted resistivity to obtain the underground three-dimensional space resistivity distribution, and determine the underground three-dimensional space water and salt distribution according to the underground three-dimensional space resistivity distribution. The present invention improves the detection and interpretation accuracy of the water and salt distribution area of ​​the underground rock and soil body.

Description

Technical Field

[0001] The present invention relates to the field of groundwater monitoring, and in particular to a system and method for remotely monitoring water and salt migration. Background Art

[0002] The combined effect of atmospheric precipitation infiltration and salt is one of the main factors that cause and aggravate the severe weathering of rock and soil. Especially for the rock and soil of caves, the combined effect of water and salt can easily lead to severe weathering of the rock and soil of caves, which poses a serious threat to the protection of cultural relics such as caves. Therefore, determining the dynamic distribution law of water and salt after atmospheric precipitation infiltration is the basis for studying the weathering mechanism of rock and soil, and it is also the premise for studying the materials and technologies for the protection of caves. At present, scholars from various countries can obtain information such as water and salt content in the rock and soil of caves with the help of hydrogeological means. At the same time, modern geophysical detection technology can also detect the abnormal resistivity information in the rock and soil of caves. Since the resistivity decreases with the increase of groundwater and salt content, this correlation is used to analyze the abnormal situation of water and salt content in the rock and soil according to the measured resistivity data. However, related research is still at the stage of static data collection, and it is difficult to obtain long-term large-scale three-dimensional dynamic information of water and salt distribution in rock and soil, resulting in inaccurate detection and interpretation of the water and salt distribution area of ​​underground rock and soil. This poses a great obstacle to the study of the migration and transformation laws of water and salt in rock and soil and the corresponding protection work of cave rock and soil. Summary of the invention

[0003] The purpose of the present invention is to provide a remote monitoring system and method for water and salt migration, so as to solve the problem of inaccurate detection of water and salt distribution areas in underground rock and soil bodies in the prior art.

[0004] To achieve the above object, the present invention provides the following solutions:

[0005] A water-salt migration remote monitoring system, comprising: a resistivity measuring device, a wireless transmission device, a temperature monitoring device and a data processing and visualization device; the resistivity measuring device and the temperature monitoring device are both connected to the wireless transmission device, and the wireless transmission device is connected to the data processing and visualization device;

[0006] The resistivity measuring device is used to measure the apparent resistivity of the underground medium of the site;

[0007] The temperature monitoring device is used to monitor and record the atmospheric temperature and underground field temperature in real time, and is also used to fit the underground field temperature;

[0008] The wireless transmission device is used to transmit the apparent resistivity and the fitted underground field temperature to the data processing and visualization device;

[0009] The data processing and visualization device is used to invert the apparent resistivity to obtain the inverted resistivity, and use the fitted underground field temperature to correct the inverted resistivity to obtain the underground three-dimensional resistivity distribution, and determine the underground three-dimensional water and salt distribution based on the underground three-dimensional resistivity distribution.

[0010] Optionally, it further includes: an outdoor storage room, a power supply device, a rainfall calculation device and a monitoring and security device; the power supply device is respectively connected to the resistivity measuring device, the wireless transmission device, the temperature monitoring device, the rainfall calculation device and the monitoring and security device; the rainfall calculation device and the monitoring and security device are both connected to the wireless transmission device;

[0011] The outdoor storage room is used to store the resistivity measuring device, the wireless transmission device and the power supply device;

[0012] The power supply device is used to provide electrical energy;

[0013] The rainfall calculation device comprises a rain gauge and a rain cup; the rainfall calculation device is used to record the rainfall at the monitoring site;

[0014] The monitoring and security device is used to monitor and protect the water-salt migration remote monitoring system.

[0015] Optionally, the outdoor storage room is located within a preset range of the intersection of any two measuring lines in the "well" measuring line;

[0016] The power supply device includes a photovoltaic solar panel and a collective power generation unit, wherein the photovoltaic solar panel is located on the top of the outdoor storage room, and the collective power generation unit is located inside the outdoor storage room;

[0017] The resistivity measuring device is located inside the outdoor storage room and is connected to the four measuring lines of the "well"-shaped measuring line;

[0018] The rainfall calculation device is located outside the outdoor storage room;

[0019] The temperature monitoring device includes an atmospheric temperature monitoring unit and an underground temperature monitoring unit; the atmospheric temperature monitoring unit is located outside the outdoor storage room and the atmospheric temperature monitoring unit is placed above the ground; the underground temperature monitoring unit is located outside the outdoor storage room and the underground temperature monitoring unit is placed below the ground; the wireless transmission device is located inside the outdoor storage room;

[0020] The monitoring and security device is located outside the outdoor storage room.

[0021] Optionally, the monitoring and security device includes a multifunctional monitoring camera.

[0022] A method for remote monitoring of water and salt migration, the method for remote monitoring of water and salt migration being applied to any of the above-mentioned remote monitoring systems for water and salt migration, the method for remote monitoring of water and salt migration comprising:

[0023] Obtain the apparent resistivity of the underground medium at the site;

[0024] Inverting the apparent resistivity to obtain an inverted resistivity;

[0025] Obtain atmospheric temperature and underground field temperature;

[0026] Fitting the atmospheric temperature and the underground field temperature to obtain a fitted underground field temperature;

[0027] The inverted resistivity is corrected using the fitted underground field temperature to obtain a three-dimensional underground resistivity distribution;

[0028] The water-salt distribution in the three-dimensional underground space is determined according to the resistivity distribution in the three-dimensional underground space.

[0029] Optionally, the step of obtaining the apparent resistivity of the underground medium of the site further includes:

[0030] Using comprehensive geophysical detection methods to detect the underground space medium structure of the site; the underground space medium structure includes the distribution of stratum structure, groundwater distribution and groundwater flow direction;

[0031] According to the underground space medium structure and in combination with the borehole histogram, determine the layout position of the water and salt migration remote monitoring system and the layout position of the survey line;

[0032] The width and depth of the ditch are determined according to the size of the survey line; the ditch is used to bury the survey line.

[0033] Optionally, fitting the atmospheric temperature and the underground field temperature to obtain a fitted underground field temperature specifically includes:

[0034] use Fitting the atmospheric temperature and the underground field temperature to obtain a fitted underground field temperature; wherein T(z,t) represents the fitted underground field temperature at a depth of z and at time t; represents the average surface temperature, obtained according to the atmospheric temperature; ΔT0 represents the surface temperature amplitude, D a represents the damping depth of surface temperature fluctuations, τ represents the temperature fluctuation calculation period; a represents the soil thermal diffusion coefficient, which is obtained according to the underground field temperature.

[0035] Optionally, the inverted resistivity is corrected using the fitted underground field temperature to obtain underground three-dimensional spatial resistivity distribution, specifically including:

[0036] According to the fitted underground field temperature, the formula ρ T(z,t) =ρ T [1+(βT-T(z,t))] corrects the inverted resistivity to obtain the corrected apparent resistivity; where ρ T(z,t) represents the corrected apparent resistivity, ρ T It represents the resistivity after inversion when the temperature of underground temperature field is T, and β represents the empirical coefficient;

[0037] The three-dimensional resistivity distribution of underground space is determined based on the corrected apparent resistivity.

[0038] Optionally, also include:

[0039] Obtain rainfall monitoring data;

[0040] Determining whether the rainfall monitoring data is positively correlated with the apparent resistivity;

[0041] If the rainfall monitoring data is positively correlated with the apparent resistivity, it is determined that the measured apparent resistivity is accurate;

[0042] If the rainfall monitoring data is not positively correlated with the apparent resistivity, it is determined that the measured apparent resistivity is inaccurate.

[0043] According to the specific embodiments provided by the present invention, the present invention discloses the following technical effects:

[0044] The present invention provides a remote monitoring system and method for water and salt migration. The system collects the apparent resistivity, atmospheric temperature and underground field temperature of the site through a resistivity measuring device and a temperature monitoring device, and fits the atmospheric temperature and underground field temperature. The apparent resistivity is inverted through a data processing and visualization device, and the inverted resistivity is corrected using the fitted underground field temperature to obtain the underground three-dimensional resistivity distribution, and generate a resistivity visualization dynamic distribution map, thereby inferring the water and salt distribution of the underground space. The present invention obtains long-term large-scale three-dimensional dynamic information on the water and salt distribution of rock and soil bodies, and improves the accuracy of detection and interpretation of the water and salt distribution area of ​​underground rock and soil bodies. BRIEF DESCRIPTION OF THE DRAWINGS

[0045] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative labor.

[0046] Figure 1 A schematic diagram of a water-salt migration remote monitoring system provided by the present invention;

[0047] Figure 2 This is a layout diagram of a remote monitoring system for water and salt migration according to an embodiment of the present invention;

[0048] Figure 3 This is a diagram of the main components of the water and salt migration remote monitoring system according to an embodiment of the present invention;

[0049] Figure 4 This is an internal layout diagram of an outdoor storage room according to an embodiment of the present invention;

[0050] Figure 5 is a schematic diagram of a survey line according to an embodiment of the present invention; wherein, Figure 5 (a) is a schematic diagram of the cable; Figure 5 (b) is a schematic diagram of electrodes;

[0051] Figure 6 It is a graph showing underground monitoring temperature at different depths and fitted underground field temperature curves according to an embodiment of the present invention;

[0052] Figure 7 It is a fitting curve diagram of underground field temperature at different depths and at different times according to an embodiment of the present invention;

[0053] Figure 8 is a cross-sectional view of an embodiment of the present invention before and after resistivity correction; wherein, Figure 8 (a) is the resistivity profile before temperature correction on July 4; Figure 8 (b) is the resistivity profile after temperature correction on July 4;

[0054] Fig. 9 A graph showing rainfall and soil moisture content according to an embodiment of the present invention;

[0055] Fig.10 This is a cross-validation diagram of rainfall and average resistivity value after temperature correction according to an embodiment of the present invention;

[0056] Fig.11 This is a resistivity dynamic distribution diagram at 2 o'clock on June 23 of an embodiment of the present invention;

[0057] Fig.12 This is a resistivity dynamic distribution diagram at 10 o'clock on June 23 of an embodiment of the present invention;

[0058] Fig.13 This is a resistivity dynamic distribution diagram at 18:00 on June 23rd according to an embodiment of the present invention;

[0059] Fig.14 This is a dynamic distribution diagram of resistivity at 2 o'clock on June 24 of an embodiment of the present invention;

[0060] Fig.15 This is a dynamic resistivity distribution diagram at 10 o'clock on June 24 of an embodiment of the present invention;

[0061] Fig.16 This is a resistivity dynamic distribution diagram at 18:00 on June 24 according to an embodiment of the present invention;

[0062] Fig.17 This is a total dynamic distribution diagram of resistivity from 2:00 on June 23 to 18:00 on June 24 according to an embodiment of the present invention;

[0063] Fig.18 A three-dimensional resistivity distribution map of underground space according to an embodiment of the present invention;

[0064] Fig.19 The underground three-dimensional water-salt distribution map of an embodiment of the present invention;

[0065] Fig. 20 A flow chart of a method for remote monitoring of water and salt migration provided by the present invention.

[0066] Explanation of symbols: 1- measuring line; 2- electrode; 3- outdoor storage room; 4- power supply device; 5- resistivity measuring device; 6- wireless transmission device; 7- data processing and visualization device; 8- temperature monitoring device; 9- monitoring and security device; 10- rainfall calculation device; 11- cable; 12- main cable; 13- electrode cable; 14- screw; 15- top plate; 16- extruded wall panel; 17- folding door; 18- resin keel floor; 19- photovoltaic solar panel; 20- collective power generation unit; 21- rain gauge; 22- rain cup; 23- thread; 24- atmospheric temperature monitoring unit; 25- underground temperature monitoring unit. DETAILED DESCRIPTION

[0067] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments 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.

[0068] The purpose of the present invention is to provide a remote monitoring system and method for water and salt migration, so as to solve the problem of inaccurate detection of water and salt distribution areas in underground rock and soil bodies in the prior art.

[0069] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, the present invention is further described in detail below with reference to the accompanying drawings and specific embodiments.

[0070] Figure 1A schematic diagram of a water-salt migration remote monitoring system provided by the present invention is shown in FIG. Figure 1 As shown, a water-salt migration remote monitoring system includes: a resistivity measuring device 5, a wireless transmission device 6, a wireless transmission device 8 and a data processing and visualization device 7. The resistivity measuring device 5 and the wireless transmission device 8 are both connected to the wireless transmission device 6, and the wireless transmission device 6 is connected to the data processing and visualization device 7.

[0071] The resistivity measuring device 5 is used to measure the apparent resistivity of the underground medium of the site. In practical applications, the resistivity measuring device 5 mainly uses the field high-density electrical method to measure the resistivity and the like. Figure 3 As shown, the resistivity measuring device 5 is located inside the outdoor storage room 3 and is connected to the four measuring lines of the "well"-shaped measuring line 1. The resistivity measuring device 5 needs to be a multi-channel electrical instrument that can perform automatic field measurements and has the function of automatic data output. This example uses a MALA-ABEM electrical instrument, and the data measured by the MALA-ABEM electrical instrument is the apparent resistivity of the underground medium of the site. The automatic measurement time interval of the MALA-ABEM electrical instrument is set to 1 hour or more, and the specific measurement time interval can be determined according to the on-site conditions.

[0072] The temperature monitoring device 8 is used to monitor and record the atmospheric temperature and underground field temperature in real time, and is also used to fit the underground field temperature. Figure 2 As shown, the temperature monitoring device 8 includes an atmospheric temperature monitoring unit 24 and an underground temperature monitoring unit 25, wherein the atmospheric temperature monitoring unit 24 is located outside the outdoor storage room 3, placed above the ground, and in contact with the atmosphere; the underground temperature monitoring unit 25 is located outside the outdoor storage room 3, placed below the ground. The temperature monitoring device 8 can monitor and record atmospheric temperature and underground field temperature change data in real time, and is used to fit the underground field temperature. The fitted underground field temperature is used for correction processing of the later resistivity data inversion results. The atmospheric temperature monitoring unit 24 can select the atmospheric temperature monitoring data of the outdoor temperature meter or the local meteorological department; the underground temperature monitoring unit 25 can select the temperature sensor deployed underground to monitor the underground temperature.

[0073] The wireless transmission device 6 is used to transmit the apparent resistivity and the fitted underground field temperature to the data processing and visualization device 7. In practical applications, after the wireless transmission device 6 is inserted into a SIM card, the data obtained by the MALA-ABEM electrical instrument can be transmitted to a designated mailbox in real time, thereby transmitting the data obtained by the resistivity measurement device 5 to a remote client in real time.

[0074] The data processing and visualization device 7 is used to invert the apparent resistivity to obtain the inverted resistivity, and use the fitted underground field temperature to correct the inverted resistivity to obtain the underground three-dimensional resistivity distribution, and determine the underground three-dimensional water and salt distribution according to the underground three-dimensional resistivity distribution. In practical applications, Figure 5 As shown, the data processing and visualization device 7 is located at the remote client, including inversion processing of the remotely transmitted data of the apparent resistivity obtained, and correcting the apparent resistivity obtained by inversion based on the fitted underground field temperature data, and generating a resistivity visualization dynamic distribution map, so as to infer the water and salt distribution of the underground space.

[0075] In a specific embodiment, the water and salt migration remote monitoring system also includes: an outdoor storage room 3, a power supply device 4, a rainfall calculation device 10 and a monitoring and security device 9; the power supply device 4 is respectively connected to the resistivity measuring device 5, the wireless transmission device 6, the wireless transmission device 8, the data processing and visualization device 8, the rainfall calculation device 10 and the monitoring and security device 9; the rainfall calculation device 10 and the monitoring and security device 9 are both connected to the wireless transmission device 6.

[0076] The outdoor storage room 3 is used to store the resistivity measuring device, the wireless transmission device and the power supply device. Figure 1 As shown, the outdoor storage room 3 is located within a preset range of the intersection of any two measuring lines 1 in the "well" measuring line, which is convenient for arranging the measuring lines 1 and saving the length of the measuring lines 1. Figure 3 As shown, the outdoor storage room 3 mainly includes a roof 15, an extruded wall panel 16, a folding door 17 and a resin keel floor 18. The main structure of the outdoor storage room 3 is made of PVC material, which is waterproof, strong and durable. The foundation of the outdoor storage room 3 needs to be higher than the ground by a certain height, and drainage ditches are dug around it to facilitate drainage. The outdoor storage room 3 and the photovoltaic solar panel 19 are fixed by anchors and anchor rods.

[0077] The power supply device 4 is used to provide electrical energy. In practical applications, the power supply device 4 is mainly used to provide power to the system for a long time in the field without interruption, such as Figure 3 As shown, the power supply device 4 includes a photovoltaic solar panel 19 and a collective power generation unit 20, wherein the photovoltaic solar panel 19 is located on the top of the outdoor storage room 3, and the collective power generation unit 20 is located inside the outdoor storage room 3. The input and output power of the power supply device 4 should meet the requirements of long-term uninterrupted power supply in the field.

[0078] The rainfall calculation device 10 includes a rain gauge and a rain cup. Figure 2As shown; the rainfall calculation device 10 is located outside the outdoor storage room 3, and the rainfall calculation device 10 is used to record the rainfall at the monitoring site, the monitored rainfall and the soil moisture content, such as Fig. 9 The monitored rainfall is used for reliability analysis of subsequent data results, as shown in Fig.10 shown.

[0079] The monitoring and security device 9 is used to monitor and protect the water and salt migration remote monitoring system. In practical applications, the monitoring and security device 9 is located outside the outdoor storage room 3. The placement of the monitoring and security device 9 ensures that the entire monitoring system area can be monitored. The monitoring and security device 9 includes a multifunctional monitoring camera, such as Figure 2 As shown, it can meet the monitoring and protection functions of the monitoring system and can remotely transmit monitoring videos.

[0080] After the water-salt migration remote monitoring system is connected, it is started and debugged, the automatic measurement time interval and data transmission are set, and the automatic measurement and data transmission system is started.

[0081] Fig. 20 A flow chart of a method for remote monitoring of water and salt migration provided by the present invention is applied to any of the remote monitoring systems for water and salt migration described above. Fig. 20 As shown, the water-salt migration remote monitoring method includes:

[0082] Step 2401: Obtain the apparent resistivity of the underground medium of the site.

[0083] Step 2402: Invert the apparent resistivity to obtain the inverted resistivity.

[0084] Step 2403: Obtain the atmospheric temperature and underground field temperature.

[0085] Step 2404: Fit the atmospheric temperature and the underground field temperature to obtain a fitted underground field temperature.

[0086] In a specific implementation, the step 2404 specifically includes:

[0087] use Fitting the atmospheric temperature and the underground field temperature to obtain a fitted underground field temperature; wherein T(z,t) represents the fitted underground field temperature at a depth of z and at time t; represents the average surface temperature, obtained according to the atmospheric temperature; ΔT0 represents the surface temperature amplitude, D a represents the damping depth of surface temperature fluctuations, τ represents the temperature fluctuation calculation period; a represents the soil thermal diffusion coefficient, which is obtained according to the underground field temperature.

[0088] Step 2405: Use the fitted underground field temperature to correct the inverted resistivity to obtain the underground three-dimensional spatial resistivity distribution.

[0089] In a specific implementation, the step 2405 specifically includes:

[0090] According to the fitted underground field temperature, the formula ρ T(z,t) =ρ T [1+(βT-T(z,t))] corrects the inverted resistivity to obtain the corrected apparent resistivity; where ρ T(z,t) Represents the corrected apparent resistivity; ρ T It represents the resistivity after inversion when the temperature of the underground temperature field is T; β represents the empirical coefficient, which is usually 0.025.

[0091] The three-dimensional resistivity distribution of underground space is determined based on the corrected apparent resistivity.

[0092] Step 2406: Determine the water-salt distribution in the three-dimensional underground space based on the resistivity distribution in the three-dimensional underground space.

[0093] In practical applications, the remote transmission data of the apparent resistivity is inverted by the least square method based on Gauss-Newton smoothing constraints, and the apparent resistivity obtained by inversion is corrected according to the fitted underground field temperature data, so as to obtain the underground three-dimensional spatial resistivity distribution under the same temperature field. The underground temperature field is fitted using atmospheric temperature and underground field temperature, and the fitted underground field temperature, i.e., the change of soil temperature with depth, is obtained, and the resistivity value is corrected.

[0094] The fitted underground field temperature calculated by the above formula is compared with the actual monitored underground field temperature, such as Figure 6 As shown, the fitting results are highly accurate and meet the work needs. Figure 7 In order to fit the underground temperature data at different depths and times calculated according to the fitting formula, the inverted apparent resistivity is corrected according to the above underground temperature fitting data. The resistivity profiles before and after correction are as follows: Figure 8 As shown; Based on the long-term monitoring data, namely, the apparent resistivity, atmospheric temperature and underground field temperature, a dynamic distribution diagram of resistivity that changes with time is generated, as shown Figure 11-17 As shown, a three-dimensional resistivity distribution map of the underground space is generated, such as Fig.18 shown.

[0095] In a specific implementation, the step 1501 also includes:

[0096] The underground space medium structure of the site is detected by using a comprehensive geophysical detection method. The underground space medium structure includes the distribution of stratum structure, groundwater distribution and groundwater flow direction.

[0097] According to the underground space medium structure and in combination with the borehole column diagram, the layout position of the water-salt migration remote monitoring system and the layout position of the survey line are determined.

[0098] The width and depth of the ditch are determined according to the size of the survey line; the ditch is used to bury the survey line.

[0099] In practical applications, according to the site conditions, firstly, the basic underground space medium structure of the site is quickly ascertained by using comprehensive geophysical detection methods such as geological radar method and high-density electrical method, and characteristic survey lines and positions are selected according to the underground space medium structure, and the survey line 1 of the water-salt migration remote monitoring system and the layout position of the water-salt migration remote monitoring system are determined in combination with the borehole column chart. The underground space medium structure includes the site's stratum structure distribution, groundwater distribution and groundwater flow direction, etc.

[0100] The survey line 1 of the water-salt migration remote monitoring system and the layout direction of the water-salt migration remote monitoring system are determined according to factors such as stratum structure distribution, groundwater distribution and groundwater flow direction.

[0101] like Figure 1 As shown, the measuring line 1 includes electrodes 2 and cables 11. The measuring line 1 is arranged vertically and crosswise as much as possible. The length of the measuring line 1 is determined by the site scale and the planned detection depth. According to the site scale, the length of the measuring line 1 can reach meters or even kilometers, which can meet the large-scale three-dimensional water and salt migration remote real-time monitoring. At the same time, the length of the measuring line 1 is generally more than five to six times the planned detection depth, and the spacing of the electrodes 2 is determined according to the detection accuracy.

[0102] The excavation width and depth of the high-density electrical method trench are determined according to the size of the electrode 2 and the cable 11, with the principle of sufficient burying and protecting the electrode 2 and the cable 11.

[0103] like Figure 4 As shown, the buried cable 11 includes a main cable 12 and an electrode cable 13 , one end of the electrode cable 13 is connected to the main cable 12 , and the other end of the electrode cable 13 is connected to the electrode 2 via a screw 14 .

[0104] like Figure 4 As shown, the buried electrode 2 is a disc-shaped electrode with a diameter of 5 cm and a height of 1 cm. The disc-shaped electrode can increase the contact area with the soil. The side of the disc-shaped electrode is provided with a thread 23 connected to the screw 14. Before the electrode 2 is buried, the electrode 2 is wrapped with bentonite to ensure a low contact resistance.

[0105] In a specific embodiment, the method for remote monitoring of water and salt migration further comprises:

[0106] Obtain rainfall monitoring data. Determine whether the rainfall monitoring data is positively correlated with the apparent resistivity; if so, determine that the measured apparent resistivity is accurate; if not, determine that the measured apparent resistivity is inaccurate.

[0107] In practical applications, based on rainfall monitoring data, such as Fig. 9 As shown, the reliability of the measured resistivity data is verified, and the correlation between the resistivity data and the water-salt distribution is analyzed, as shown in Fig.10 As shown. Since the resistivity data increases with the decrease of salt concentration in groundwater, and the increase of rainfall will reduce the salt concentration in groundwater, the resistivity data and rainfall are in a positive correlation. If the measured resistivity data and rainfall satisfy this relationship, it proves that the measured resistivity data is reliable. At the same time, based on the above relationship between resistivity data, salt concentration in groundwater, and rainfall data, the underground three-dimensional water-salt distribution can be inferred based on the measured resistivity data and rainfall data, as shown in Fig.19 shown.

[0108] The present invention uses a comprehensive geophysical detection method and combines the borehole column chart to determine the layout position of the water-salt migration remote monitoring system and the survey line; and excavates the high-density electrical survey line ditch and buries the electrode. The water-salt migration remote monitoring system is installed, and the water-salt migration remote monitoring system includes an outdoor storage room 3, a power supply device 4, a resistivity measurement device 5, a wireless transmission device 6, a data processing and visualization device 7, a wireless transmission device 8, a rainfall calculation device 10, and a monitoring and security device 9. Then, automatic measurement and data transmission settings are performed, and system connection debugging and startup are performed. Finally, data processing and visualization analysis are performed. The present invention realizes the use of geophysical methods such as high-density electrical methods to monitor the dynamic distribution of resistivity in underground space. The time-varying visualized dynamic distribution diagram of resistivity is used to infer the water-salt content in rainwater. The resistivity of groundwater with different salt contents is different, and the water-salt distribution in underground space is further inferred, and the dynamic monitoring of water-salt migration in rock and soil is completed, providing a strong technical guarantee for the protection of cultural relics such as grotto rock and soil.

[0109] The present invention uses high-density electrical geophysical exploration technology to invert the apparent resistivity of underground rock and soil, uses the fitted underground field temperature data to correct the inverted apparent resistivity, and performs reliability analysis through rainfall data. The ground three-dimensional electrical exploration probe and electrode layout are optimized, and the measurement range can reach the meter level or even the kilometer level, which can meet the large-scale three-dimensional water and salt migration remote real-time monitoring, and obtain large-scale three-dimensional resistivity data of cave rock mass, which makes the detection and interpretation of the water and salt distribution area of ​​underground rock and soil more accurate.

[0110] In addition, the present invention utilizes a power supply device 4 that can provide continuous power for a long time, an automatic measurement system (resistivity measurement device 5 and wireless transmission device 8) and a wireless transmission device 6, which overcomes the problem that the current high-density electrical method is difficult to monitor for a long time, and utilizes the correlation between geophysical signals and the water and salt content of rock and soil to infer the three-dimensional distribution of water and salt in underground rock and soil, solves the technical problem of dynamic monitoring of water and salt movement in rock and soil such as grottoes, and provides technical support for the protection of cultural relics such as grotto rock and soil.

[0111] The various embodiments in this specification are described in a progressive manner, and each embodiment focuses on the differences from other embodiments. The same or similar parts between the various embodiments can be referenced to each other.

[0112] The principles and implementation methods of the present invention are described in this article using specific examples. The description of the above embodiments is only used to help understand the method and core idea of ​​the present invention. At the same time, for those skilled in the art, according to the idea of ​​the present invention, there will be changes in the specific implementation methods and application scope. In summary, the content of this specification should not be understood as limiting the present invention.

Claims

1. A remote monitoring system for water and salt migration, characterized in that: include: A resistivity measuring device, a wireless transmission device, a temperature monitoring device, a rainfall calculation device and a data processing and visualization device; the resistivity measuring device, the temperature monitoring device and the rainfall calculation device are all connected to the wireless transmission device, and the wireless transmission device is connected to the data processing and visualization device; The resistivity measuring device is used to measure the apparent resistivity of the underground medium of the site; The temperature monitoring device is used to monitor and record the atmospheric temperature and underground field temperature in real time, and is also used to fit the underground field temperature; Fitting the atmospheric temperature and the underground field temperature to obtain a fitted underground field temperature specifically includes: use Fitting the atmospheric temperature and the underground field temperature to obtain a fitted underground field temperature; wherein T(z,t) represents the fitted underground field temperature at a depth of z and at time t; represents the average surface temperature, obtained according to the atmospheric temperature; ΔT0 represents the surface temperature amplitude, D a represents the damping depth of surface temperature fluctuations, τ represents the temperature fluctuation calculation period; a represents the soil thermal diffusion coefficient, which is obtained according to the underground field temperature; The wireless transmission device is used to transmit the apparent resistivity and the fitted underground field temperature to the data processing and visualization device; The rainfall calculation device comprises a rain gauge and a rain cup; the rainfall calculation device is used to record the rainfall at the monitoring site; The data processing and visualization device is used to invert the apparent resistivity to obtain the inverted resistivity, correct the inverted resistivity using the fitted underground field temperature to obtain the underground three-dimensional resistivity distribution, and determine the underground three-dimensional water-salt distribution based on the underground three-dimensional resistivity distribution; The inverted resistivity is corrected using the fitted underground field temperature to obtain the underground three-dimensional spatial resistivity distribution, specifically including: According to the fitted underground field temperature, the formula ρ T(z,t) =ρ T [1+(βT-T(z,t))] corrects the inverted resistivity to obtain the corrected apparent resistivity; where ρ T(z,t) represents the corrected apparent resistivity, ρ T It represents the resistivity after inversion when the temperature of underground temperature field is T, and β represents the empirical coefficient; The three-dimensional resistivity distribution of underground space is determined based on the corrected apparent resistivity.

2. The water and salt migration remote monitoring system according to claim 1, characterized in that: Also includes: Outdoor storage, power supply and surveillance security equipment; The power supply device is respectively connected to the resistivity measuring device, the wireless transmission device, the temperature monitoring device, the rainfall calculation device and the monitoring and security device; the monitoring and security device is connected to the wireless transmission device; The outdoor storage room is used to store the resistivity measuring device, the wireless transmission device and the power supply device; The power supply device is used to provide electrical energy; The monitoring and security device is used to monitor and protect the water-salt migration remote monitoring system.

3. The water and salt migration remote monitoring system according to claim 2, characterized in that: The outdoor storage room is located within the preset range of the intersection of any two measuring lines in the "well" measuring line; The power supply device includes a photovoltaic solar panel and a collective power generation unit, wherein the photovoltaic solar panel is located on the top of the outdoor storage room, and the collective power generation unit is located inside the outdoor storage room; The resistivity measuring device is located inside the outdoor storage room and is connected to the four measuring lines of the "well"-shaped measuring line; The rainfall calculation device is located outside the outdoor storage room; The temperature monitoring device includes an atmospheric temperature monitoring unit and an underground temperature monitoring unit; the atmospheric temperature monitoring unit is located outside the outdoor storage room and the atmospheric temperature monitoring unit is placed above the ground; the underground temperature monitoring unit is located outside the outdoor storage room and the underground temperature monitoring unit is placed below the ground; the wireless transmission device is located inside the outdoor storage room; The monitoring and security device is located outside the outdoor storage room.

4. The water and salt migration remote monitoring system according to claim 2, characterized in that: The monitoring and security device comprises a multifunctional monitoring camera.

5. A method for remote monitoring of water and salt migration, characterized in that: The water-salt migration remote monitoring method is applied to the water-salt migration remote monitoring system according to any one of claims 1 to 4, and the water-salt migration remote monitoring method comprises: Obtain the apparent resistivity of the underground medium at the site; Inverting the apparent resistivity to obtain an inverted resistivity; Obtain atmospheric temperature and underground field temperature; Fitting the atmospheric temperature and the underground field temperature to obtain a fitted underground field temperature specifically includes: use Fitting the atmospheric temperature and the underground field temperature to obtain a fitted underground field temperature; wherein T(z,t) represents the fitted underground field temperature at a depth of z and at time t; represents the average surface temperature, obtained according to the atmospheric temperature; ΔT0 represents the surface temperature amplitude, D a represents the damping depth of surface temperature fluctuations, τ represents the temperature fluctuation calculation period; a represents the soil thermal diffusion coefficient, which is obtained according to the underground field temperature; The inverted resistivity is corrected using the fitted underground field temperature to obtain the underground three-dimensional spatial resistivity distribution, specifically including: According to the fitted underground field temperature, the formula ρ T(z,t) =ρ T [1+(βT-T(z,t))] corrects the inverted resistivity to obtain the corrected apparent resistivity; where ρ T(z,t) represents the corrected apparent resistivity, ρ T It represents the resistivity after inversion when the temperature of underground temperature field is T, and β represents the empirical coefficient; Determining the three-dimensional resistivity distribution of the underground space according to the corrected apparent resistivity; The water-salt distribution in the three-dimensional underground space is determined according to the resistivity distribution in the three-dimensional underground space.

6. The method for remote monitoring of water and salt migration according to claim 5, characterized in that: The obtaining of the apparent resistivity of the underground medium of the site also includes: Using comprehensive geophysical detection methods to detect the underground space medium structure of the site; the underground space medium structure includes the distribution of stratum structure, groundwater distribution and groundwater flow direction; According to the underground space medium structure and in combination with the borehole histogram, determine the layout position of the water and salt migration remote monitoring system and the layout position of the survey line; The width and depth of the ditch are determined according to the size of the survey line; the ditch is used to bury the survey line.

7. The method for remote monitoring of water and salt migration according to claim 6, characterized in that: Also includes: Obtain rainfall monitoring data; Determining whether the rainfall monitoring data is positively correlated with the apparent resistivity; If the rainfall monitoring data is positively correlated with the apparent resistivity, it is determined that the measured apparent resistivity is accurate; If the rainfall monitoring data is not positively correlated with the apparent resistivity, it is determined that the measured apparent resistivity is inaccurate.

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