Post-mining grouting position selection method for thick-layer roof sandstone water disasters

Abstract

The invention discloses a method for selecting a post-mining grouting position for thick-layer roof sandstone water disasters. The method comprises the following steps: (1) finely probing a geologic body of a to-be-grouted area; (2) representing the development degree of the native fracture and the water inflow based on a water inflow observation result in the working face pushing and mining process in combination with the development degree of the native fracture, and evaluating the development condition of the water guide channel of the working face; (3) predicting the development height of the water flowing fractured zone; (4) selecting a grouting layer position; and (5) selecting a grouting position. The method disclosed by the invention has the following beneficial effects: 1, fine exploration work is carried out, comprehensive and accurate cognition of geological conditions is realized, and a foundation is built for subsequent work; 2, the grouting layer position and the plane position are selected scientifically and reasonably, blind selection is effectively avoided, and the water control and roof reinforcement effects are guaranteed; errors and waste are reduced, and construction efficiency and quality are improved.

Description

Technical Field

[0001] The present invention belongs to the field of coal water control, and particularly relates to a method for selecting the post-mining grouting position for the water disaster of thick-layer roof sandstone. Background Technique

[0002] In recent years, with the large-scale mining stage of the Jurassic coalfield in western China, the prevention and control of coal seam roof water disasters has become a key technical problem restricting the safe and efficient production of mines.

[0003] As one of the 13 large coal bases in the country, the Binchang mining area has serious water disasters in thick-layer sandstone fissures. The coal seams in this area are relatively thick, the mining height of the working face is relatively large, the development height of the water-conducting fissure zone is relatively large, and the upper part of the middle section of the Luohe Formation, a water-rich aquifer, communicates with the working face in a large area during the mining process of the working face. At the same time, the thickness of the strong aquifer in the upper part of the middle section of the Luohe Formation is relatively large and the seepage recharge is abundant, resulting in a large amount of water inflow still existing after the mining of the working face.

[0004] In view of the above problems, the traditional post-mining grouting hole layout scheme usually predicts the height of the water-conducting fissure development zone based on theoretical calculations, selects the grouting horizon as the end of the development of the water-conducting fissure development zone, and grouts at a fixed hole spacing on the plane. However, the water-conducting fissure zone is distributed in a three-dimensional network and develops non-uniformly, and it is difficult to accurately locate the development area of the water-conducting channel by traditional drilling or geophysical exploration means. At the same time, the post-mining grouting holes are prone to hole collapse and plugging, and the construction difficulty is relatively large. To cover the possible water-conducting fissure zone, a large number of grouting holes need to be arranged, but blindly expanding the grouting range will lead to material waste and poor economy. Summary of the Invention

[0005] Object of the Invention: Aiming at the Jurassic coalfield in western China, especially in areas with serious water disasters in thick-layer sandstone fissures such as the Binchang mining area, facing technical problems such as thick coal seams, large mining heights, large development heights of water-conducting fissure zones that are distributed in a three-dimensional network and non-uniformly, difficult to accurately locate the development area of water-conducting channels, large construction difficulty of post-mining grouting holes, and material waste caused by blindly expanding the grouting range, the present invention provides a method for selecting the post-mining grouting position for the water disaster of thick-layer roof sandstone. The present invention constructs a three-dimensional geological model by integrating seismic exploration, drilling and real-time water inflow monitoring data, combines the dynamic prediction algorithm of the water-conducting fissure zone and the identification mechanism of the water-conducting channel, accurately determines the grouting horizon and the plane target area, thereby effectively solving the deficiencies of the prior art, realizing the effective diffusion of the slurry, plugging the main water-conducting channels to reduce the water inflow of the working face, strengthening the extremely thick sandstone layer to ensure the effective support of the main key strata, and then slowing down the ground subsidence caused by coal seam mining, and improving the safety and economy of coal mining.

[0006] Technical Solution: A method for selecting the post-mining grouting position for the water disaster of thick-layer roof sandstone, comprising the following steps:

[0007] (1) Conduct a detailed exploration of the geological body in the grouting area;

[0008] (2) Based on the observed water inflow during the face extraction process and combined with the degree of development of primary fractures, characterize the degree of development of primary fractures and the water inflow, and evaluate the development of water-conducting channels in the working face;

[0009] (3) Predict the development height of the water-conducting fracture zone;

[0010] (4) Selection of grouting horizons;

[0011] (5) Selection of grouting positions.

[0012] Furthermore, step (1) includes the following steps:

[0013] (11) Collect and organize the historical data of the grouting area;

[0014] (12) Build the structural framework of the grouting area;

[0015] (13) Use the pseudo-acoustic inversion method to perform lithology inversion on the grouting area and interpret the lithology of the grouting area;

[0016] (14) Use the multi-attribute inversion method to predict the water-richness of the grouting area;

[0017] (15) Based on the ant body technology, interpret the development and distribution pattern of fractures in the grouting area;

[0018] Even further, the specific steps of step (11) are as follows:

[0019] (111) Collect seismic data before the face extraction, ensuring that the data covers a sufficient range of the grouting area and has an appropriate resolution to clearly reflect the general structure and interface conditions of the underground rock strata;

[0020] (112) Carefully sort out the drilling data, which includes the lithology description and physical and mechanical property test results of different drilling positions, depths, hole diameters, and the obtained cores;

[0021] (113) Comprehensively integrate the existing geological data, including the regional stratigraphic columnar section, geological structure map, rock mineral composition analysis report, and the mining parameters recorded during the past production process, the encountered abnormal geological phenomena and the corresponding treatment measures;

[0022] (114) Standardize the various types of data collected, unifying the coordinate system, data format, and depth datum.

[0023] Even further, step (12) includes the following steps:

[0024] (121) Use the Petrel geological modeling software, combined with geostatistical methods, to identify the main stratigraphic interfaces and faults based on the reflection wave characteristics of seismic data;

[0025] (122) Refer to the drilling data to accurately position and calibrate the key stratigraphic and tectonic positions, and build the tectonic framework of the area to be grouted with the help of the macroscopic stratigraphic framework and tectonic background provided by geological data.

[0026] Furthermore, step (13) includes the following steps:

[0027] (131) Standardize the natural gamma curve;

[0028] (132) Multiply the standardized natural gamma curve by a coefficient to make the value range of the calculated curve consistent with that of the conventional P-wave velocity curve, and at the same time make a density curve with a density of 2 g / cm 3 constant;

[0029] (133) According to the time-depth relationship of the conventional acoustic velocity, complete the acoustic impedance inversion based on the pseudo-acoustic curve, the constant density curve, and the post-stack seismic data, adjust the inversion parameters, and select the best inversion result as the lithology inversion body.

[0030] Furthermore, step (14) includes the following steps:

[0031] (141) Perform square root, square, reciprocal, and logarithmic processing on the characteristic curve and seismic data, and perform correlation analysis on the resistivity curve and the processed seismic attribute data, and select the seismic attribute with higher correlation as the sensitive attribute;

[0032] (142) Perform neural network training on the resistivity curve and the sensitive seismic attribute to obtain a neural network training model;

[0033] (143) Apply the neural network model to the entire area to be grouted to obtain a water-richness inversion body.

[0034] Furthermore, step (15) includes the following steps:

[0035] (151) Preprocess the post-stack seismic data to enhance the characterization characteristics of the seismic data for fractures, where:

[0036] The methods for preprocessing the post-stack seismic data include structural smoothing, variance volume, chaos volume, and boundary enhancement;

[0037] (152) Adjust the ant volume operation parameters, select the optimal result, and predict the fracture development area in the area to be grouted.

[0038] Furthermore, in step (2), the degree of fissure development at each plane position of the working face is divided according to the seismic fissure interpretation results, and the ratio of the fissure development height from the coal seam roof to the bottom boundary of the strong aquifer in the middle section of the Luohe Formation is used as a characterization index of the primary fissure development degree a;

[0039] In step (2), the water inflow data is collected in real time based on the water inflow monitoring equipment on the working face, with the average water inflow per day as the basic data and the difference between the average water inflow of two consecutive days as 1000m 3 The percentage b of / h is the specific representation of the water inflow;

[0040] In step (2), the development degree of the water-conducting channel is c=a+b, where:

[0041] If 0≤c<0.5, the area to be grouted is determined to be a normal area;

[0042] If 0.5≤c<1, the area to be grouted is determined to be a key attention area;

[0043] If 1≤c, the area to be grouted is determined to be an area that must be treated.

[0044] Further, step (3) comprises the following steps:

[0045] S1. Calculation of hard rock ratio coefficient: Collect the measured water-conducting fracture zone development height data in the area to be grouting, find out the mining height, floor burial depth, and working face span at the corresponding position, and calculate the hard rock ratio coefficient at the measured position of the water-conducting fracture zone development height;

[0046] S2. Multiple regression analysis: Based on the data obtained in step S1, multiple regression analysis is performed to determine the influence weight of each parameter on the height of the water-conducting fracture development, and a multi-parameter water-conducting fracture zone development height calculation formula applicable to the grouting area is summarized;

[0047] S3. Lithology inversion: Based on seismic inversion, the top and bottom layers of the coal seam to be mined and the lithology distribution characteristics of the overlying strata of the coal seam are interpreted;

[0048] S4, time-depth conversion: Based on the results of well seismic calibration, complete the velocity field construction and time-depth conversion to convert the time domain interpretation results into the depth domain, and obtain the buried depth of the coal seam floor and the thickness of the coal seam;

[0049] S5. Calculation of the development height of the water-conducting fissure zone: Based on the interpretation results obtained in steps S3 and S4, the thickness of hard rock within 15 - 20 times the coal seam thickness is statistically calculated, and the hard rock proportion coefficient within the area to be grouted is calculated. The coal seam thickness, the buried depth of the coal seam floor, and the hard rock proportion coefficient obtained by inverting steps S3 and S4 are combined with the working face span given by the mine to substitute into the multi-parameter water-conducting fissure zone development height calculation formula obtained in step S2 to complete the prediction of the development height of the water-conducting fissure zone.

[0050] Further, step (4) includes the following steps:

[0051] Based on the distribution of the bottom boundary of the thick and strong aquifer in the upper part of the middle section of the He Formation obtained in step (1) and the development height of the water-conducting fissure zone predicted in step (3), the spatial positions of the two are judged, where:

[0052] If the water-conducting fissure zone develops into the thick and strong aquifer in the upper part of the middle section of the He Formation, the grouting horizon is selected within the range of 0 - 15 m upward from the lower bottom boundary of the thick and strong aquifer in the upper part of the middle section of the He Formation;

[0053] If the water-conducting fissure zone does not develop into the thick and strong aquifer in the upper part of the middle section of the He Formation, the grouting horizon is selected at the development end of the water-conducting fissure zone.

[0054] Further, step (5) includes the following steps:

[0055] Based on the three-dimensional visualization platform, determine the planar position of post-mining grouting according to the evaluation result of the water-conducting channel completed in step (2);

[0056] According to the spatial relationship between the water-conducting fissure zone and the strong aquifer determined in step (4), determine the optimal grouting horizon;

[0057] Comprehensively consider the grouting planar position and the grouting horizon to optimize the drilling trajectory.

[0058] Beneficial effects: A method for selecting the post-mining grouting position for thick roof sandstone water damage disclosed by the present invention has the following beneficial effects:

[0059] 1. The present invention conducts fine exploration work by integrating multi-source data such as seismic, drilling, geology, and production, realizes a comprehensive and accurate understanding of the geological situation, and lays a solid foundation for subsequent work;

[0060] 2. The selection of the grouting horizon and the planar position is scientific and reasonable, effectively avoiding blind selection, and ensuring the water control and roof reinforcement effects;

[0061] 3. By integrating various key information with the help of a 3D visualization platform, planning and adjustment are carried out by synthesizing multiple factors in the 3D space, changing the traditional fuzzy positioning method. Construction workers can accurately construct according to the detailed design documents and visualization guidance diagrams, reducing mistakes and waste, and improving construction efficiency and quality. On this basis, remarkable water disaster prevention and control effects are achieved, effectively reducing the water inflow, improving the roof stability, slowing down the ground subsidence, saving resources and costs, enhancing the operability of project implementation, and comprehensively ensuring the safety and sustainable development of coal mining, with great application value and promotion prospects. BRIEF DESCRIPTION OF THE DRAWINGS

[0062] Figure 1 It is a flowchart of a method for selecting the post-mining grouting position for water disaster in thick-layer roof sandstone disclosed by the present invention. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0063] The following details the specific embodiments of the present invention.

[0064] The "range" disclosed by the present invention is defined in the form of a lower limit and an upper limit. A given range is defined by selecting a lower limit and an upper limit, and the selected lower limit and upper limit define the boundary of a specific range. The range defined in this way can include or not include the end values, and can be combined arbitrarily, that is, any lower limit can be combined with any upper limit to form a range. For example, if a range of 10 - 50 is listed for a specific parameter, ranges of 10 - 40 and 20 - 50 are also contemplated. In addition, if the minimum range values 1 and 2 are listed, and if the maximum range values 3, 4, and 5 are listed, the following ranges are all contemplated: 1 - 3, 1 - 4, 1 - 5, 2 - 3, 2 - 4, and 2 - 5. In this application, unless otherwise specified, the numerical range "a - b" represents the abbreviated representation of any real number combination between a and b, where a and b are both real numbers. For example, the numerical range "0 - 5" means that all real numbers between "0 - 5" have been fully listed in this article, and "0 - 5" is only the abbreviated representation of these numerical combinations.

[0065] If there is no special instruction, all the embodiments and optional embodiments of this application can be combined with each other to form a new technical solution.

[0066] If there is no special instruction, all the technical features and optional technical features of this application can be combined with each other to form a new technical solution.

[0067] Unless otherwise specified, all steps of this application can be carried out sequentially or randomly, preferably sequentially. For example, the method includes steps (a) and (b), which means that the method may include steps (a) and (b) carried out sequentially, or may also include steps (b) and (a) carried out sequentially. For example, it is mentioned that the method may further include step (c), which means that step (c) can be added to the method in any order. For example, the method may include steps (a), (b), and (c), or may also include steps (a), (c), and (b), or may also include steps (c), (a), and (b), etc.

[0068] Unless otherwise specified, the "including" and "comprising" mentioned in this application mean open-ended, and can also be closed-ended. For example, the "including" and "comprising" can mean that other components not listed may also be included or comprised, or may only include or comprise the listed components.

[0069] Unless otherwise specified, the reaction is carried out under normal temperature and normal pressure conditions.

[0070] Unless otherwise specified, all parts or percentages are by weight or weight percentage.

[0071] In the present invention, the substances used are all known substances, which can be purchased or synthesized by known methods.

[0072] In the present invention, the devices or equipment used are all conventional devices or equipment known in the field and can be purchased.

[0073] Aiming at the treatment of roof sandstone water in Jurassic coal resources in the western part of China, a method for selecting the post-mining grouting position for thick-layer roof sandstone water disaster is proposed, including the following steps:

[0074] (1) Conduct a detailed exploration of the geological body in the area to be grouted;

[0075] ① Collect and organize the historical data of the area to be grouted

[0076] Systematically collect seismic data before the working face is pushed and mined, ensuring that the data covers a sufficient range of the area to be grouted and has an appropriate resolution, and can clearly reflect the general structure and interface conditions of the underground rock strata. At the same time, carefully sort out the drilling data, including detailed parameters such as the positions, depths, and pore diameters of different drill holes, as well as key information such as the lithology description of the obtained cores and the test results of physical and mechanical properties. Comprehensively integrate the existing geological data, such as regional stratigraphic columns, geological structure maps, rock mineral composition analysis reports, etc., and production data such as mining parameters recorded during past production processes, abnormal geological phenomena encountered, and corresponding treatment measures.

[0077] Standardize all kinds of collected data, unify the coordinate system, data format, depth datum, etc., so as to carry out seamless fusion and comprehensive analysis subsequently.

[0078] ② Construction framework building and geological feature analysis

[0079] Using petrel geological modeling software, combined with geostatistical methods, identify main stratigraphic interfaces, faults and other structural information based on the reflection wave characteristics of seismic data, accurately locate and calibrate key stratigraphic and structural positions with reference to drilling data, and build a detailed and accurate structural framework of the area to be grouted with the help of the macroscopic stratigraphic framework and structural background provided by geological data. Based on the structural framework and comprehensive analysis of multi-source data, deeply interpret the lithology, water-richness and fracture distribution characteristics of the area to be grouted.

[0080] ③ Lithology interpretation

[0081] Adopt the pseudo-acoustic inversion method for lithology inversion. First, standardize the natural gamma curve to eliminate the errors caused by instruments and other factors. Then, multiply the standardized natural gamma curve by a coefficient to make the value range of the calculated curve consistent with that of the conventional compressional wave velocity curve, and at the same time make a density curve with a density of 2g / cm 3 constant. Finally, according to the time-depth relationship of the conventional acoustic velocity, complete the acoustic impedance inversion based on the pseudo-acoustic curve, constant density curve and post-stack seismic data, adjust the inversion parameters, and optimize the best inversion result as the lithology inversion body.

[0082] ④ Water-richness interpretation

[0083] Adopt the multi-attribute inversion method for water-richness prediction, that is, use the probabilistic neural network to establish the non-linear relationship between the water-richness characteristic curve and various sensitive seismic attribute combinations to realize the direct inversion of the water-richness of the area to be grouted. First, perform square root, square, reciprocal and logarithm processing on the characteristic curve and seismic data, and conduct correlation analysis on the resistivity curve and the processed seismic attribute data to optimize the seismic attributes with higher correlation as sensitive attributes. Then, train the neural network with the resistivity curve and sensitive seismic attributes to obtain the neural network training model. Finally, apply the neural network model to the entire area to be grouted to obtain the water-richness inversion body.

[0084] ⑤ Fracture interpretation

[0085] Predict the fracture-developed area based on the ant body technology. First, preprocess the post-stack seismic data, such as structural smoothing, variance body, chaotic body and boundary enhancement, to enhance the characterization characteristics of the seismic data for fractures. Then, adjust the ant body operation parameters, optimize the best result, and predict the fracture-developed area.

[0086] (2) Based on the observation results of water inflow during the mining process of the working face and the development of primary fractures, the degree of development of primary fractures and water inflow were characterized, and the development of water channels in the working face was evaluated.

[0087] ① Characterization of fissure development degree

[0088] According to the results of seismic fissure interpretation, the degree of fissure development at each plane position of the working face is divided, and the ratio of the fissure development height from the coal seam roof to the bottom boundary of the strong aquifer in the middle section of the Luohe Formation is used as the characterization index. For example, if the coal seam roof is 300m away from the bottom boundary of the strong aquifer in the middle section of the Luohe Formation, and there are 100m of fissures developed between them, then its characterization index is a = 50%.

[0089] ② Characterization of water inflow

[0090] The water inflow monitoring equipment on the working face collects water inflow data in real time. The average water inflow per day is used as the basic data, and the difference between the average water inflow of two consecutive days is 1000m 3 The percentage of / h is a specific representation of the water inflow. For example, the average water inflow on the first day of the working face is 1500m 3 / h, the average water inflow at the working face on the second day was 2000m 3 / h, the characterization value is b=(2000-1500) / 1000=50%.

[0091] ③Water channel assessment

[0092] The development degree of the water channel c = a + b. If 0 ≤ c < 0.5, the area to be grouted is determined to be a normal area; if 0.5 ≤ c < 1, the area to be grouted is determined to be a key attention area; if 1 ≤ c, the area to be grouted is determined to be an area that must be treated.

[0093] (3) Prediction of the height of water-conducting fracture zones

[0094] S1. Calculation of hard rock ratio coefficient: Collect the measured water-conducting fracture zone development height data in the area to be grouting, find out the mining height, floor burial depth, and working face span at the corresponding position, and calculate the hard rock ratio coefficient at the measured position of the water-conducting fracture zone development height;

[0095] S2. Multiple regression analysis: Based on the data obtained in step S1, multiple regression analysis is performed to determine the influence weight of each parameter on the height of the water-conducting fracture development, and a multi-parameter water-conducting fracture zone development height calculation formula applicable to the grouting area is summarized;

[0096] S3. Lithology inversion: Based on seismic inversion, the top and bottom layers of the coal seam to be mined and the lithology distribution characteristics of the overlying strata of the coal seam are interpreted;

[0097] S4. Time-depth conversion: Based on the well-seismic calibration results, construct the velocity field and perform time-depth conversion to transform the interpretation results in the time domain into the depth domain, obtaining the burial depth of the coal seam floor and the thickness of the coal seam.

[0098] S5. Calculation of the development height of the water-conducting fissure zone: Based on the interpretation results obtained in steps S3 and S4, count the thickness of hard rock within 15 - 20 times the coal seam thickness, calculate the hard rock proportion coefficient in the area to be grouted, and substitute the coal seam thickness, the burial depth of the coal seam floor, and the hard rock proportion coefficient obtained by inverting steps S3 and S4, along with the working face span given by the mine, into the multi-parameter formula for calculating the development height of the water-conducting fissure zone obtained in step S2 to complete the prediction of the development height of the water-conducting fissure zone.

[0099] (4) Selection of grouting horizons

[0100] Based on the distribution of the lower boundary of the thick and strong aquifer in the upper-middle part of the Luohe Formation obtained in step (1) and the development height of the water-conducting fissure zone calculated in step (3), judge their spatial positions. If the water-conducting fissure zone develops into the thick and strong aquifer in the upper-middle part of the Luohe Formation, select the grouting horizon within the range of 0 - 15 m upward from the lower bottom boundary of the thick and strong aquifer in the upper-middle part of the Luohe Formation; if the water-conducting fissure zone does not develop into the thick and strong aquifer in the upper-middle part of the Luohe Formation, select the end of the development of the water-conducting fissure zone as the grouting horizon.

[0101] (5) Selection of grouting positions

[0102] Based on 3D visualization technology, determine the planar position of post-mining grouting according to the evaluation results of water-conducting channels completed in step (2); determine the optimal grouting horizon according to the spatial relationship between the water-conducting fissure zone and the strong aquifer determined in step (4); comprehensively consider the grouting planar position and the grouting horizon to optimize the drilling trajectory.

[0103] Economic analysis:

[0104] The present invention has good economic efficiency and has significant manifestations in many aspects. First of all, in terms of reducing material costs, unlike the traditional grouting method that blindly expands the grouting range and wastes a lot of materials, the present invention accurately focuses on key areas through detailed exploration, accurate analysis of water-conducting fracture zones and water-conducting channels, scientific and reasonable grouting layer selection, and the use of a three-dimensional visualization platform to determine the grouting position, thereby avoiding material waste and reducing procurement costs. Secondly, in terms of reducing construction costs, it can avoid repeated construction, and with precise positioning, construction personnel can effectively construct according to the design at one time, and can also improve construction efficiency and reduce labor, equipment rental and other time-related costs. Furthermore, it can reduce the indirect economic costs caused by water damage losses, effectively control water damage, reduce water inflow, avoid equipment damage, mining interruption, etc., ensure production continuity, and improve overall economic benefits. From the perspective of long-term benefits, its reinforcement of the roof can slow down ground collapse, reduce surrounding compensation and repair and management costs, maintain long-term stable operation, save economic expenditures for coal mining enterprises from multiple dimensions, and has great economic value and promotion advantages.

[0105] The above describes the embodiments of the present invention in detail. However, the present invention is not limited to the above embodiments, and various changes can be made within the knowledge of ordinary technicians in the relevant technical field without departing from the purpose of the present invention.

Claims

1. A method for selecting the post-mining grouting position for thick roof sandstone water hazards, characterized in that It includes the following steps: (1) Conduct a fine exploration of the geological body in the area to be grouted; (2) Based on the observed water inflow during the coal face extraction process and combined with the degree of development of primary fractures, characterize the degree of development of primary fractures and the water inflow, and evaluate the development of water-conducting channels in the coal face; (3) Predict the development height of the water-conducting fracture zone; (4) Selection of the grouting horizon; (5) Selection of the grouting position, where: Step (1) includes the following steps: (11) Collect and sort out the historical data of the area to be grouted; (12) Build the tectonic framework of the area to be grouted; (13) Use the pseudo-acoustic inversion method to conduct lithology inversion on the area to be grouted and interpret the lithology of the area to be grouted; (14) Use the multi-attribute inversion method to predict the water-richness of the area to be grouted; (15) Interpret the development and distribution pattern of fractures in the area to be grouted based on the ant body technology.

2. The method for selecting the post-mining grouting position for thick-layer roof sandstone water damage according to claim 1, characterized in that The specific steps of Step (11) are as follows: (111) Collect seismic data before the coal face extraction, ensuring that the data covers a sufficient range of the area to be grouted and has appropriate resolution, and can clearly reflect the general structure and interface conditions of the underground rock strata; (112) Carefully sort out the drilling data, and the drilling data includes the lithology description and physical and mechanical property test results of different borehole positions, depths, hole diameters, and the obtained cores; (113) Comprehensively integrate the existing geological data, including the regional stratigraphic columnar section, geological structure map, rock mineral composition analysis report, and the mining parameters recorded during the past production process, the encountered abnormal geological phenomena and the corresponding treatment measures; (114) Conduct standardization processing on the collected various data, and unify the coordinate system, data format, and depth datum.

3. The method for selecting the post-mining grouting position for thick-layer roof sandstone water hazard as described in claim 1, characterized in that Step (12) includes the following steps: (121) Use the petrel geological modeling software, combined with the geostatistical method, to identify the main stratigraphic interfaces and faults based on the reflection wave characteristics of the seismic data; (122) Refer to the drilling data to accurately locate and calibrate the key stratigraphic and tectonic positions, and build the tectonic framework of the area to be grouted with the help of the macroscopic stratigraphic framework and tectonic background provided by the geological data.

4. A method for selecting the post-mining grouting position for thick-layer roof sandstone water disaster as described in claim 1, characterized in that, Step (13) includes the following steps: (131) Conduct standardization processing on the natural gamma curve; (132) Multiply the standardized natural gamma ray curve by a coefficient to make the value range of the calculated curve consistent with that of the conventional P-wave velocity curve. Meanwhile, create a density curve with a density of 2 g / cm 3 constant; (133) According to the time-depth relationship of the conventional acoustic wave velocity, complete the acoustic impedance inversion based on the pseudo-acoustic curve, constant density curve, and post-stack seismic data, adjust the inversion parameters, and select the best inversion result as the lithology inversion body.

5. A method for selecting the post-mining grouting position for thick-layer roof sandstone water damage as described in claim 1, characterized in that, Step (14) includes the following steps: (141) Conduct square root, square, reciprocal, and logarithmic processing on the characteristic curve and seismic data, and conduct correlation analysis on the resistivity curve and the processed seismic attribute data, and select the seismic attributes with higher correlation as the sensitive attributes; (142) Conduct neural network training on the resistivity curve and the sensitive seismic attributes to obtain a neural network training model; (143) Apply the neural network model to the entire area to be grouted to obtain a water-richness inversion body.

6. The selection method of the post-mining grouting position for thick-layer roof sandstone water disaster according to claim 1, wherein, Step (15) includes the following steps: (151) Preprocessing the post-stack seismic data to enhance the characterization characteristics of the seismic data on the fault, wherein: The preprocessing methods for post-stack seismic data include structural smoothing, variance body, chaos body and boundary enhancement; (152) Adjust the ant body calculation parameters, select the best result, and predict the fracture development area in the area to be grouting.

7. The method for selecting the post-mining grouting position for thick-layer roof sandstone water disaster according to claim 1, characterized in that In step (2), the degree of fracture development at each plane position of the working face is divided according to the seismic fracture interpretation results, and the ratio of the fracture development height from the coal seam roof to the bottom boundary of the strong aquifer in the middle section of the Luohe Formation is used as a characterization index of the primary fracture development degree a; In step (2), the water inflow data is collected in real time based on the water inflow monitoring equipment on the working face. The average daily water inflow is used as the basic data, and the percentage b of the difference between the average water inflows of two adjacent days in 1000 m 3 / h is used as the specific representation of the water inflow; In step (2), the development degree of the water-conducting channel is c=a+b, where: If 0≤c<0.5, the area to be grouted is determined to be a normal area; If 0.5≤c<1, the area to be grouted is determined to be a key attention area; If 1≤c, the area to be grouted is determined to be an area that must be treated.

8. The method for selecting the post-mining grouting position for thick-layer roof sandstone water disaster as described in claim 1, wherein, Step (3) comprises the following steps: S1. Calculation of hard rock ratio coefficient: Collect the measured water-conducting fracture zone development height data in the area to be grouting, find out the mining height, floor burial depth, and working face span at the corresponding position, and calculate the hard rock ratio coefficient at the measured position of the water-conducting fracture zone development height; S2. Multiple regression analysis: Based on the data obtained in step S1, multiple regression analysis is performed to determine the influence weight of each parameter on the height of the water-conducting fracture development, and a multi-parameter water-conducting fracture zone development height calculation formula applicable to the grouting area is summarized; S3. Lithology inversion: Based on seismic inversion, the top and bottom layers of the coal seam to be mined and the lithology distribution characteristics of the overlying strata of the coal seam are interpreted; S4, time-depth conversion: Based on the results of well seismic calibration, complete the velocity field construction and time-depth conversion to convert the time domain interpretation results into the depth domain, and obtain the buried depth of the coal seam floor and the thickness of the coal seam; S5. Calculation of the height of the water-conducting fracture zone: Based on the interpretation results obtained in steps S3 and S4, the hard rock thickness within 15 to 20 times the thickness of the coal seam is statistically calculated, and the hard rock proportion coefficient in the area to be grouting is calculated. The coal seam thickness, coal seam floor burial depth and hard rock proportion coefficient obtained by inversion in steps S3 and S4 are combined with the working face span given by the mine and substituted into the multi-parameter water-conducting fracture zone development height calculation formula obtained in step S2 to complete the prediction of the height of the water-conducting fracture zone.

9. The method for selecting the post-mining grouting position for thick-layer roof sandstone water disaster according to claim 1, characterized in that, Step (4) comprises the following steps: Based on the bottom boundary distribution of the thick and strong aquifer in the middle section of the river obtained in step (1) and the height of the water-conducting fracture zone obtained by prediction in step (3), the spatial positions of the two are determined, where: If the water-conducting fracture zone develops into the strong aquifer in the upper middle section of the river group, the grouting layer shall be selected within the range of 0-15m upward from the lower boundary of the strong aquifer in the upper middle section of the river group; If the water-conducting fracture zone has not developed to the strong aquifer in the upper middle section of the river formation, the grouting layer will be selected as the end of the development of the water-conducting fracture zone.

10. A method for selecting the post-mining grouting position for thick-layer roof sandstone water disaster as described in claim 1, characterized in that, Step (5) comprises the following steps: Based on the three-dimensional visualization platform, determine the plane position of post-mining grouting according to the water channel evaluation results completed in step (2); Determine the best grouting layer according to the spatial relationship between the water-conducting fracture zone and the strong aquifer determined in step (4); Optimize the drilling trajectory by comprehensively considering the grouting plane position and grouting horizon.

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