Method for finely depicting spatial architecture characteristics of southwest karst water-containing system

Abstract

The invention discloses a method for finely depicting spatial architecture characteristics of a southwest karst water-containing system, which comprises the following steps: S1, acquiring basic geological information of the karst water-containing system in a research area, analyzing karst development characteristics from upstream to downstream, and selecting a section with gradually changed karst development characteristics; spatial distribution and trend information of karst fissures are obtained, positions and extension directions of karst spring and underground river in a hidden area are obtained through geophysical detection, and resistivity values of pores, fissures and pipelines are identified by using a high-density resistivity imaging technology. The invention provides a brand-new fine description method for the spatial architecture characteristics of the karst water-containing system by integrating a high-density resistivity imaging technology, a hydrochemical analysis technology and a trace element detection method and combining a relationship between a hydrological attenuation coefficient and a karst development degree. The method can comprehensively and accurately reveal the spatial distribution characteristics and hydrological characteristics of the secondary architecture of the karst system.

Description

Technical Field

[0001] The present invention relates to the technical field of karst water-bearing system spatial architecture, and in particular to a method for finely depicting the spatial architecture characteristics of a southwestern karst water-bearing system. Background Art

[0002] The southwest region is characterized by a karst hydrogeological environment and rich groundwater resources. However, due to the strong heterogeneity of the karst aquifer system, the hydrological dynamics of the groundwater in the region are highly variable in time and space. In the karst aquifer system, hydrological dynamics are affected by many factors, including topography, precipitation, karst development level, groundwater flow path, etc. These factors make the development and utilization of the karst aquifer system complex and difficult. Existing karst hydrological research focuses on the analysis of specific profiles. In particular, the combination of geophysical exploration and hydrological dynamic observation technology still has limitations in many applications. Traditional karst hydrological research methods mainly rely on geological drilling, field sampling and single hydrological curve analysis. However, due to the heterogeneity and complexity of the karst system, it is often difficult to accurately depict the spatial characteristics of groundwater flow and storage, resulting in inaccurate simulation results of hydrological processes and facing great challenges in the rational allocation and protection of water resources.

[0003] In current research and applications, there is a lack of a comprehensive technical means to comprehensively and finely characterize the spatial structural characteristics of karst water-bearing systems. Although existing technical means have made some progress in karst hydrogeological exploration, due to the complexity of the geological environment, many existing technologies have failed to effectively reveal the hydrological characteristics of the secondary structure of the karst system. There is a lack of comprehensive understanding of hydrological dynamic changes, and it is difficult to meet the needs of watershed scale and regional water resources management. Therefore, there is an urgent need to develop a new technical solution to improve the ability to accurately characterize the spatial structural characteristics of karst water-bearing systems and provide a theoretical basis for more scientific water resources management and disaster prevention and mitigation. Summary of the Invention

[0004] The present invention provides a method for finely characterizing the spatial architecture characteristics of the southwestern karst water-bearing system, which can effectively solve the problems raised in the above-mentioned background technology.

[0005] To achieve the above objectives, the present invention provides the following technical solution: a method for finely characterizing the spatial architecture characteristics of the southwestern karst water-bearing system, comprising the following steps:

[0006] S1. Obtain basic geological information of the karst water-bearing system in the study area, analyze the karst development characteristics from upstream to downstream, and select sections with gradual changes in karst development characteristics;

[0007] S2. Conduct field measurements on the selected sections to obtain the spatial distribution and direction of karst fissures. Use geophysical exploration to determine the location and extension direction of karst springs and underground rivers in concealed areas. Use high-density resistivity imaging technology to identify the resistivity values ​​of pores, fissures, and pipelines.

[0008] S3. Deploy automatic monitoring equipment at all water outcrops in the basin to obtain parameters such as water level, temperature, and conductivity. Conduct high-frequency monitoring in conjunction with precipitation scenarios and analyze the corresponding relationship between the secondary structure hydrological attenuation coefficient and the characteristics of the water-bearing medium.

[0009] S4. Regularly collect water samples from springs, skylights, boreholes, and watershed outlets, use portable water quality analyzers to measure the concentrations of trace elements and major water chemical components, and analyze the relationship between their change slopes and the degree of karst development;

[0010] S5. Integrate the acquired karst fissures, pipeline spatial distribution information, hydrological curves, and trace element analysis data to determine the karstification characteristics, spatial distribution characteristics, and karst development degree of the secondary structure;

[0011] S6. Couple and validate geophysical survey results with hydrochemical information and isotope tracer data, and extend them to the watershed scale to analyze the vertical and lateral spatial heterogeneity of hydrogeological units.

[0012] According to the above technical solution, the geophysical exploration technology used in S2 includes high-density resistivity imaging technology, which is used to distinguish the resistivity differences among karst pores, cracks and pipelines.

[0013] According to the above technical solution, the portable water quality analyzer used for determining trace elements in the water sample in S4 is an analyzer produced by the French company PONSEL;

[0014] The trace elements tested included K + 、Na + , Ca 2+ Mg 2+ 、Cl - 、SO4 2- 、HCO3 - 、NO3 - , SiO2, Al, Cu, Pb, Zn, Cr, Ni, Co, Cd, Mn, As, Hg, Ba and Sr.

[0015] According to the above technical solution, in S3, automatic monitoring probes produced by Canada's Solinst Company are used to monitor the main water outfall points in the basin;

[0016] The probe has the function of automatically recording water level, temperature and conductivity with high precision;

[0017] The monitoring frequency is set dynamically according to different precipitation scenarios. The monitoring frequency is recorded every 6 hours in the dry season, increased to once every 1 hour in the rainy season, and further increased to once every 15 minutes during heavy rain.

[0018] According to the above technical solution, the monitoring data is uploaded to the remote database platform in real time via Bluetooth or GPRS communication module for storage and pre-processing, and is automatically correlated and analyzed in combination with historical precipitation, temperature and water level data;

[0019] The hydrological attenuation coefficient is obtained by fitting the rainfall-runoff response curve and then coupled with the spatial structural characteristics of the water-bearing medium for analysis. It is used to determine the response characteristics and water conduction capacity of fractured, pore- or pipe-type water-conducting media at different time periods, thereby achieving dynamic identification and classification of the water conduction characteristics of the karst secondary structure.

[0020] According to the above technical solution, in S6, a multi-source data fusion method is used to spatially couple geophysical exploration data, hydrochemical characteristic data and isotope tracer results, and a GIS spatial analysis platform is used to construct a three-dimensional karst geological spatial model of the secondary architecture.

[0021] According to the above technical solution, S6 specifically includes:

[0022] Convert high-density resistivity imaging results into iso-resistivity slices to map the location and extension trends of pores, fractures, and pipes;

[0023] The trend of water chemical composition and trace element concentration was analyzed by principal component analysis (PCA) to reduce the dimension and extract the main controlling factors.

[0024] Then, the water source, age and flow direction information from the isotope tracing results are spatially interpolated to form a spatial coupling layer of different source information;

[0025] Finally, different information layers are superimposed through ArcGIS or GeoModeller platform, and a visual three-dimensional karst water-bearing system model is established in combination with regional geological structure and bedding characteristics.

[0026] According to the above technical solution, when determining the spatial distribution characteristics of karst fissures and pipelines in S5, multi-temporal geophysical detection combined with field verification is used to improve the recognition accuracy;

[0027] Specifically, it involves performing multiple high-density resistivity imaging on the same profile in different seasons and hydrological scenarios, and identifying the dynamic changes in electrical responses caused by groundwater activity by comparing the changes in resistivity responses at each time phase, which serves as an important indicator for judging the activity of fractures or pipelines.

[0028] At the same time, we selected typical resistivity anomaly areas to arrange drilling or conduct geophysical verification to obtain real underground structure information. We then conducted regression analysis on the identification results combined with measured geological data to determine the extension direction, connection mode and distribution density of karst fissures, and to divide the karst structural units into highly conductive, weakly conductive and water-isolating units.

[0029] In addition, by constructing a spatial network model of karst fissures and water-conducting channels, their connectivity and hydraulic connections are analyzed, thus providing basic geological structure input conditions for subsequent karst water-bearing system flow field simulation.

[0030] According to the above technical solution, when collecting and analyzing water samples in S4, in addition to conventional chemical composition and trace element analysis, a variety of stable isotopes and radioactive isotopes are introduced to trace the source and migration path of the water.

[0031] According to the above technical solution, the stable isotopes are used to identify different water source types such as precipitation, soil water, and deep circulation water;

[0032] The radioactivity is used to determine the age and confinement of groundwater.

[0033] Compared with the existing technology, the beneficial effects of the present invention are as follows: the structure of the present invention is scientific and reasonable, and it is safe and convenient to use. By integrating high-density resistivity imaging technology, hydrochemical analysis technology and trace element detection method, combined with the relationship between hydrological attenuation coefficient and karst development degree, a new method for fine characterization of the spatial structure characteristics of karst water-bearing systems is proposed, which can comprehensively and accurately reveal the spatial distribution characteristics and hydrological characteristics of the secondary structure of the karst system, and overcome the shortcomings of traditional technology in finely identifying karst hydrological dynamics and spatial structure. Compared with the existing technology, the present invention can accurately characterize the spatial heterogeneity of karst groundwater flow and storage, enhance the ability to identify the spatial structure of karst water-bearing systems, and provide strong technical support for the rational allocation, optimized management and disaster prevention and mitigation of water resources in the basin. By accurately analyzing the karst hydrological dynamics and spatial structure, it can effectively improve the efficiency of water resource utilization and provide more efficient and accurate technical solutions for regional hydrogeological research, thereby promoting the further development of karst hydrogeology theory and application. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] The accompanying drawings are used to provide further understanding of the present invention and constitute a part of the specification. They are used to explain the present invention together with the embodiments of the present invention and do not constitute a limitation of the present invention.

[0035] In the attached figure:

[0036] Figure 1 It is a schematic structural diagram of the method steps of the present invention. DETAILED DESCRIPTION

[0037] The preferred embodiments of the present invention are described below with reference to the accompanying drawings. It should be understood that the preferred embodiments described herein are only used to illustrate and explain the present invention, and are not used to limit the present invention.

[0038] Example: Figure 1 As shown, the present invention provides a technical solution, a method for finely characterizing the spatial architecture characteristics of the southwestern karst water-bearing system, comprising the following steps:

[0039] S1. Obtain basic geological information of the karst water-bearing system in the study area, analyze the karst development characteristics from upstream to downstream, and select sections with gradual changes in karst development characteristics;

[0040] S2. Conduct field measurements on the selected sections to obtain the spatial distribution and direction of karst fissures. Use geophysical exploration to determine the location and extension direction of karst springs and underground rivers in concealed areas. Use high-density resistivity imaging technology to identify the resistivity values ​​of pores, fissures, and pipelines.

[0041] S3. Deploy automatic monitoring equipment at all water outcrops in the basin to obtain parameters such as water level, temperature, and conductivity. Conduct high-frequency monitoring in conjunction with precipitation scenarios and analyze the corresponding relationship between the secondary structure hydrological attenuation coefficient and the characteristics of the water-bearing medium.

[0042] S4. Regularly collect water samples from springs, skylights, boreholes, and watershed outlets, use portable water quality analyzers to measure the concentrations of trace elements and major water chemical components, and analyze the relationship between their change slopes and the degree of karst development;

[0043] S5. Integrate the acquired karst fissures, pipeline spatial distribution information, hydrological curves, and trace element analysis data to determine the karstification characteristics, spatial distribution characteristics, and karst development degree of the secondary structure;

[0044] S6. Couple and validate geophysical survey results with hydrochemical information and isotope tracer data, and extend them to the watershed scale to analyze the vertical and lateral spatial heterogeneity of hydrogeological units.

[0045] According to the above technical solution, the geophysical exploration technology used in S2 includes high-density resistivity imaging technology, which is used to distinguish the resistivity differences among karst pores, cracks and pipelines.

[0046] According to the above technical solution, the portable water quality analyzer used in S4 to determine the trace elements in the water sample is an analyzer produced by the French company PONSEL;

[0047] The trace elements tested included K + 、Na + , Ca 2+ Mg 2+ 、Cl -、SO4 2- 、HCO3 - 、NO3 - , SiO2, Al, Cu, Pb, Zn, Cr, Ni, Co, Cd, Mn, As, Hg, Ba and Sr.

[0048] According to the above technical solution, in S3, automatic monitoring probes produced by Canada’s Solinst Company were used to monitor the main water outcropping points in the basin;

[0049] The probe has high-precision automatic recording function of water level, temperature and conductivity;

[0050] The monitoring frequency is set dynamically according to different precipitation scenarios. The monitoring frequency is recorded every 6 hours in the dry season, increased to every 1 hour in the rainy season, and further increased to every 15 minutes during heavy rain to capture sudden hydrological dynamic changes.

[0051] According to the above technical solution, monitoring data is uploaded to a remote database platform in real time via Bluetooth or GPRS communication modules for storage and preprocessing. It then performs automated correlation analysis based on historical precipitation, temperature, and water level data to extract the response patterns of substructures at different hydrological stages, and then calculate the hydrological attenuation coefficient corresponding to each precipitation event.

[0052] The hydrological attenuation coefficient is obtained by fitting the rainfall-runoff response curve and then coupled with the spatial structural characteristics of the water-bearing medium for analysis. It is used to determine the response characteristics and water conduction capacity of fractured, pore- or pipe-type water-conducting media at different time periods, thereby achieving dynamic identification and classification of the water conduction characteristics of the karst secondary structure.

[0053] According to the above technical solution, in S6, a multi-source data fusion method is used to spatially couple geophysical exploration data, hydrochemical characteristic data and isotope tracer results, and a GIS spatial analysis platform is used to construct a three-dimensional karst geological spatial model with a secondary architecture.

[0054] According to the above technical solution, S6 specifically includes: converting the high-density resistivity imaging results into equivalent resistivity slices to map the location and extension trends of pores, fractures and pipelines;

[0055] The trend of water chemical composition and trace element concentration was analyzed by principal component analysis (PCA) to reduce the dimension and extract the main controlling factors.

[0056] The water source, age, and flow direction information from the isotope tracing results are then spatially interpolated to form a spatial coupling layer of different source information. Finally, the different information layers are superimposed using ArcGIS or GeoModeller platforms, and a visual three-dimensional karst water system model is established in combination with regional geological structure and bedding characteristics.

[0057] This model not only visualizes the three-dimensional structure of karst fissures and pipeline systems, but also simulates the response time lag and spatial heterogeneity of each water-conducting unit in a secondary watershed, thereby achieving a dynamic and detailed depiction of the spatial structure of the southwestern karst water-bearing system, providing theoretical support and predictive basis for regional water resources scheduling and groundwater disaster prevention and control.

[0058] According to the above technical solution, when determining the spatial distribution characteristics of karst fissures and conduits in S5, multi-temporal geophysical detection combined with field verification is used to improve the identification accuracy;

[0059] Specifically, it involves performing multiple high-density resistivity imaging on the same profile in different seasons and hydrological scenarios, and identifying the dynamic changes in electrical responses caused by groundwater activity by comparing the changes in resistivity responses at each time phase, which serves as an important indicator for judging the activity of fractures or pipelines.

[0060] At the same time, we selected typical resistivity anomaly areas for drilling or geophysical verification to obtain real underground structure information and improve the reliability of resistivity interpretation. We combined the measured geological data with regression analysis of the identification results to determine the extension direction, connection mode and distribution density of karst fissures, and to divide the karst structural units into high-conductivity, low-conductivity and water-isolating karst units.

[0061] In addition, by constructing a spatial network model of karst fissures and water channels, their connectivity and hydraulic connection are analyzed, thus providing basic geological structure input conditions for subsequent karst water-bearing system flow field simulation and improving the accuracy of describing groundwater migration laws under different hydrological scenarios.

[0062] According to the above technical solution, when collecting and analyzing water samples in S4, in addition to conventional chemical composition and trace element analysis, a variety of stable isotopes and radioactive isotopes are introduced to trace the source and migration path of the water.

[0063] According to the above technical solution, stable isotopes are used to identify different water source types such as precipitation, soil water, and deep circulation water;

[0064] Radioactivity is used to determine the age and confinement of groundwater;

[0065] By jointly analyzing different isotope indicators in the same water sample, the water body's recharge source, migration path, residence time and renewal capacity are comprehensively determined. The isotope results are spatially superimposed and analyzed with resistivity distribution, trace element concentration, geological structure characteristics, etc., and a coupled relationship map of water body source and karst structure is constructed to indicate the recharge type and migration channel of different secondary structural units. This method not only improves the accuracy of identifying the spatial heterogeneity of karst hydrological systems, but also enhances the ability to functionally locate different karst structural units, thereby providing theoretical support for karst water resource protection and high-risk area prediction.

[0066] Finally, it should be noted that the above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art will be able to modify the technical solutions described in the aforementioned embodiments or substitute equivalents for some of the technical features. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention shall be included within the scope of protection of the present invention.

Claims

1. A method for finely characterizing the spatial architecture of karst water-bearing systems in Southwest China, characterized by: The steps include: S1. Obtain basic geological information of the karst water-bearing system in the study area, analyze the karst development characteristics from upstream to downstream, and select sections with gradual changes in karst development characteristics; S2. Conduct field measurements on the selected sections to obtain the spatial distribution and direction of karst fissures. Use geophysical exploration to determine the location and extension direction of karst springs and underground rivers in concealed areas. Use high-density resistivity imaging technology to identify the resistivity values ​​of pores, fissures, and pipelines. S3. Deploy automatic monitoring equipment at all water outcrops in the basin to obtain parameters such as water level, temperature, and conductivity. Conduct high-frequency monitoring in conjunction with precipitation scenarios and analyze the corresponding relationship between the secondary structure hydrological attenuation coefficient and the characteristics of the water-bearing medium. S4. Regularly collect water samples from springs, skylights, boreholes, and watershed outlets, use portable water quality analyzers to measure the concentrations of trace elements and major water chemical components, and analyze the relationship between their change slopes and the degree of karst development; S5. Integrate the acquired karst fissures, pipeline spatial distribution information, hydrological curves, and trace element analysis data to determine the karstification characteristics, spatial distribution characteristics, and karst development degree of the secondary structure; S6. Couple and validate geophysical survey results with hydrochemical information and isotope tracer data, and extend them to the watershed scale to analyze the vertical and lateral spatial heterogeneity of hydrogeological units.

2. A method for finely characterizing the spatial architecture characteristics of the karst water-bearing system in Southwest China according to claim 1, characterized in that: The geophysical exploration technology used in the S2 includes high-density resistivity imaging technology, which is used to distinguish the resistivity differences among karst pores, fractures and pipelines.

3. The method for finely characterizing the spatial architecture characteristics of the karst water-bearing system in Southwest China according to claim 1, characterized in that: The portable water quality analyzer used in S4 to determine the trace elements in the water sample is an analyzer produced by PONSEL, a French company; The trace elements tested included K + 、Na + , Ca 2+ Mg 2+ 、Cl - 、SO4 2- 、HCO3 - 、NO3 - , SiO2, Al, Cu, Pb, Zn, Cr, Ni, Co, Cd, Mn, As, Hg, Ba and Sr.

4. The method for finely characterizing the spatial architecture characteristics of the karst water-bearing system in Southwest China according to claim 1, characterized in that: In S3, automatic monitoring probes produced by Canada's Solinst Company are used to monitor the main water outfall points in the basin; The probe has the function of automatically recording water level, temperature and conductivity with high precision; The monitoring frequency is set dynamically according to different precipitation scenarios. The monitoring frequency is recorded every 6 hours in the dry season, increased to once every 1 hour in the rainy season, and further increased to once every 15 minutes during heavy rain.

5. The method for finely characterizing the spatial architecture characteristics of the karst water-bearing system in Southwest China according to claim 4, characterized in that: The monitoring data is uploaded to the remote database platform in real time via Bluetooth or GPRS communication modules for storage and pre-processing, and automatically correlated with historical precipitation, temperature and water level data for analysis; The hydrological attenuation coefficient is obtained by fitting the rainfall-runoff response curve and then coupled with the spatial structural characteristics of the water-bearing medium for analysis. It is used to determine the response characteristics and water conduction capacity of fractured, pore- or pipe-type water-conducting media at different time periods, thereby achieving dynamic identification and classification of the water conduction characteristics of the karst secondary structure.

6. The method for finely characterizing the spatial architecture characteristics of the karst water-bearing system in Southwest China according to claim 1, characterized in that: In S6, a multi-source data fusion method is used to spatially couple geophysical exploration data, hydrochemical characteristic data and isotope tracer results, and a GIS spatial analysis platform is used to construct a three-dimensional karst geological spatial model with a secondary architecture.

7. The method for finely characterizing the spatial architecture characteristics of the karst water-bearing system in Southwest China according to claim 6, characterized in that: The S6 specifically includes: Convert high-density resistivity imaging results into iso-resistivity slices to map the location and extension trends of pores, fractures, and pipes; The trend of water chemical composition and trace element concentration was analyzed by principal component analysis (PCA) to reduce the dimension and extract the main controlling factors. Then, the water source, age and flow direction information from the isotope tracing results are spatially interpolated to form a spatial coupling layer of different source information; Finally, different information layers are superimposed through ArcGIS or GeoModeller platform, and a visual three-dimensional karst water-bearing system model is established in combination with regional geological structure and bedding characteristics.

8. The method for finely characterizing the spatial architecture characteristics of the karst water-bearing system in Southwest China according to claim 1, characterized in that: When determining the spatial distribution characteristics of karst fissures and conduits in S5, multi-temporal geophysical detection combined with field verification is used to improve identification accuracy; Specifically, it involves performing multiple high-density resistivity imaging on the same profile in different seasons and hydrological scenarios, and identifying the dynamic changes in electrical responses caused by groundwater activity by comparing the changes in resistivity responses at each time phase, which serves as an important indicator for judging the activity of fractures or pipelines. At the same time, we selected typical resistivity anomaly areas to arrange drilling or conduct geophysical verification to obtain real underground structure information. We then conducted regression analysis on the identification results combined with measured geological data to determine the extension direction, connection mode and distribution density of karst fissures, and to divide the karst structural units into highly conductive, weakly conductive and water-isolating karst units. In addition, by constructing a spatial network model of karst fissures and water-conducting channels, their connectivity and hydraulic connections are analyzed, thus providing basic geological structure input conditions for subsequent karst water-bearing system flow field simulation.

9. The method for finely characterizing the spatial architecture characteristics of the karst water-bearing system in Southwest China according to claim 1, characterized in that: When collecting and analyzing water samples in S4, in addition to conventional chemical composition and trace element analysis, a variety of stable isotopes and radioactive isotopes are introduced to trace the source and migration path of the water.

10. A method for finely characterizing the spatial architecture characteristics of the karst water-bearing system in Southwest China according to claim 9, characterized in that: The stable isotopes are used to identify different water source types such as precipitation, soil water, and deep circulation water; The radioactivity is used to determine the age and confinement of groundwater.

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