Riverbed downriver fault fine exploration method and system based on directional drilling group cooperative detection

Abstract

The application discloses a riverbed along-river fault fine exploration method based on directional drilling group cooperative detection, which comprises the following steps: S1, acquiring riverbed along-river fault data; S2, supplementing the collected data; S3, directional drilling layout and exploration; S4, while-drilling multi-parameter monitoring; S5, fault space positioning; S6, fault mud fine dating; the riverbed along-river fault fine exploration system based on directional drilling group cooperative detection comprises a data acquisition module, a data supplement module, a directional drilling layout module, a while-drilling multi-parameter monitoring module, a fault space positioning module and a fault mud fine dating module; the application has a significant advantage in three-dimensional space distribution capability; the permeability of a fault zone and rock mass deformation characteristics are quantified through parameter linkage analysis, dynamic data support is provided for fault activity evaluation, through directional drilling group cooperative operation, reliable and efficient decision support is provided for geological disaster prevention and control and engineering planning.

Description

Technical Field

[0001] This application relates to the fields of engineering geological exploration and geological disaster prevention and control, and in particular to a method and system for refined exploration of riverbed faults along the river based on collaborative detection of directional borehole groups. Background Technology

[0002] Hydropower is a clean, renewable, pollution-free energy source with low operating costs. It facilitates peak power regulation, improving resource utilization and overall economic and social benefits. Given the increasing scarcity of traditional energy sources globally, countries worldwide are prioritizing hydropower development and making full use of water resources. Hydropower development is a requirement for energy industry development and structural adjustment, for resource utilization and regional economic revitalization, and for environmental protection and sustainable development.

[0003] Water conservancy and hydropower are fundamental industries for economic and social development. Water conservancy and hydropower projects have long construction cycles, large investments, and involve many collaborating departments. They are also greatly affected by natural resources, topography, geology, and hydrological and meteorological conditions.

[0004] The regional background of hydropower construction sites is complex, and many are located in mountainous areas with various adverse physical and geological phenomena. The geological conditions at the base of structures such as regulating reservoirs, dams, and water diversion tunnels are complex. Preliminary investigations should focus on identifying the occurrence, nature, scale, extension, filling and cementation of major faults and compressional fracture zones in the dam site area, as well as the activity of faults since the Late Pleistocene. Particular attention should be paid to investigating river-dipping faults and faults with moderate to gentle dips. Previously, riverbed tunnels were typically used to explore river-dipping faults. However, due to the long exploration period, large capital investment, high safety risks, and lengthy approval procedures for explosives, riverbed tunnel exploration is no longer suitable for the current needs of hydropower engineering surveys.

[0005] Bedding faults are a type of fault in structural geology where the fault plane is parallel to the bedding plane of rock strata or pre-existing weak surfaces (such as unconformities). Their formation is closely related to longitudinal bending folding, and when inter-layer slip reaches the scale of a fault, they exhibit the typical characteristics of a bedding fault. The direction of displacement is often determined by tectonic markers rather than stratigraphic offset effects, and these faults are widely developed in geological structures such as foreland fold-fault zones, the base of detached folds, and the deep parts of shovel-shaped normal faults. Their development process is of great indicative significance for studying lithospheric deformation mechanisms and regional tectonic evolution.

[0006] Currently, the major project is located in a high mountain and canyon area with dense vegetation on both banks and steep slopes in some sections, making it unsuitable for road construction or the installation of cableway relocation equipment. Therefore, it is not feasible to install bidirectional paired inclined boreholes across the river. Vertical drilling would require multiple boreholes, and underwater drilling is risky, costly, and time-consuming. Therefore, to advance the project, new methods are needed to explore riverbed faults in the high mountain and canyon area. Summary of the Invention

[0007] The main objective of this application is to provide a method and system for refined exploration of riverbed faults along the river based on collaborative detection of directional borehole groups. This addresses the limitations of existing technologies in high mountain and canyon areas where road construction and the deployment of cableway relocation equipment are not feasible, thus hindering the deployment of bidirectional paired cross-river inclined boreholes. Furthermore, vertical boreholes require multiple boreholes, and underwater drilling presents high risks, high costs, and long cycles.

[0008] To achieve the above objectives, this application provides the following technical solution: A method for refined riverbed fault exploration based on coordinated directional borehole drilling includes the following steps: S1. Obtain riverbed fault data: Collect digital topographic maps and geological structure data of riverbed faults along the river, and construct a three-dimensional image based on the collected riverbed fault data along the river. S2. Supplement the collected data: Through field geological surveys, supplement the mapping of active faults with surface outcrops and detect hidden active faults to improve the three-dimensional image; S3. Directional drilling layout and exploration: Based on the three-dimensional image, set the position of the opening point and target point, design the directional drilling point and directional drilling intensity, draw the borehole profile trajectory, use high-strength wireline coring drill rod and wireline coring tool for drilling feed, and use artificial directional drilling tools to force the borehole axis to bend and extend according to the designed trajectory. S4. Multi-parameter monitoring while drilling: The drilling measurement system is used to collect parameters such as drilling pressure fluctuation frequency, natural gamma value, mud loss, and borehole trajectory deviation in real time, and to calculate the fault conditions of the rock mass in the borehole. S5. Fault spatial positioning: During the directional drilling process, its spatial trajectory parameters are measured in real time, and the drilling geological anomaly points and geological anomaly body types are determined based on the fault identification characteristics. After obtaining the spatial coordinates of each geological anomaly point from the directional drilling trajectory parameters, the accurate spatial parameters of the fault are calculated, and the fault along the riverbed is drilled. S6. Fine dating of fault gouge: After directional drilling of fault material along the riverbed, finely stratify the fault material and collect dating samples for high-precision dating.

[0009] In this embodiment, preferably, the riverbed fault data along the river direction in S1 is used to construct a three-dimensional image: High-resolution digital topographic data were acquired using a drone equipped with a multispectral camera. ; Riverbed fault samples were obtained through geological drilling. The fracture density and lithological assemblage of the fault samples were analyzed to obtain the particle size data of the fault gouge. With sorting coefficient and extracting crack length and opening degree ; By crack length and opening degree Calculate the connectivity of 3D crack network data ; Then, a weighted average method was used to assess connectivity. Particle size data With sorting coefficient The parameters of the fracture particle size are fused together to generate the comprehensive fracture particle size parameters of the fault gouge; Finally, the comprehensive fracture particle size parameters of the fault gouge were compared with high-resolution digital topographic map data. By integrating the fault data along the riverbed, a three-dimensional image is constructed. As a further improvement to this application, the improved three-dimensional image in S2 is obtained by field geological survey mapping of active faults exposed on the surface. The mapping elements include fault type, geomorphological elements, stratigraphic elements, igneous rock elements, and displacement. Furthermore, the active faults exposed on the surface or the concealed active faults with upper fault points shallower than 8m are detected. The active fault identification trench should span the entire fault zone.

[0010] As a further improvement to this application, the specific steps of borehole layout and exploration in S3 are as follows: S301: Select the borehole trajectory in the 3D image, design the directional drilling point and directional drilling intensity based on the location of the borehole opening point and target point, and draw the borehole profile trajectory; design the borehole structure based on the borehole trajectory design, site and engineering geological conditions, drilling equipment, drilling methods and processes, final borehole diameter, directional drilling tool type and method, and in-hole tests and inspections. S302: Directional drilling equipment and tools include drilling rigs, flushing fluid equipment, drilling tools, measuring and control instruments, and auxiliary tools; S303: Securely install directional drilling equipment and tools; S304: High-strength wireline coring drill rods and wireline coring tools are used. The high-strength wireline coring drill rods and wireline coring tools use tapered guide coring bits. When drilling curved holes, the changes in the drill torque should be observed at any time. If the torque changes significantly, the drilling pressure should be reduced appropriately or the drill tool should be moved. After the torque returns to normal, coring should continue. If the torque is still abnormal, the drill should be lifted for inspection. S305: Drilling trajectory refers to the change in the spatial position of each point on the drilling axis, characterized by spatial elements such as hole depth, inclination angle, azimuth angle, elevation, horizontal length, and offset. Directional drilling trajectory uses artificial skew-making tools to force the drilling axis to bend and extend according to the designed trajectory. S306: After core sampling, borehole flushing and wall sealing are carried out, and accident prevention and handling are also carried out. S307: Continuous coring in directional drilling, including coring in inclined sections, coring in curved sections, and coring in horizontal sections.

[0011] As a further improvement to this application, the steps of designing the trajectory in S3 are as follows: The spatial trajectory parameters of directional drilling can be calculated from three basic parameters: hole depth, dip angle, and azimuth angle. The hole depth is obtained by the drill rod accumulation method, while the dip angle and azimuth angle are measured in real time by the drilling measurement system during the drilling process. With the hole opening point as the origin, the positive X-axis direction is the extension direction of the main borehole orientation line, the positive Y-axis direction is rotated 90° horizontally clockwise, and the positive Z-axis direction is vertically upward. Using the basic parameters obtained from the measurement while drilling system, the borehole trajectory is calculated using the mean angle total distance method.

[0012] As a further improvement to this application, the specific steps for analyzing the fault in the borehole rock mass in S4 are as follows: Deploy a measurement-while-drilling system to collect real-time data on drill pressure fluctuation frequency, natural gamma value, mud loss, and borehole trajectory deviation. The dominant frequency component of the drilling pressure fluctuation frequency is extracted by Fourier transform and used to determine the dynamic response characteristics of the fault zone. The lithological anomaly index of the fault zone was calculated by using correlation analysis between natural gamma values ​​and lithological combination data. By analyzing the correlation between mud loss and borehole trajectory deviation, the permeability of the fault zone and the deformation characteristics of the rock mass are quantified. Input the above parameters into the mathematical model to calculate the fault conditions of the rock mass inside the borehole.

[0013] As a further improvement to this application, the lithological anomaly index of the fault zone is calculated as follows: ; in, It is expressed as a natural gamma anomaly, used to quantify the lithological anomaly characteristics of fault zones; The natural gamma value of the homogeneous region is used as a baseline value. It is represented as the dominant frequency component of the drilling pressure fluctuation frequency, reflecting the dynamic response characteristics of the fault zone; It is expressed as the mineral percentage, reflecting the compositional characteristics of fault gouge; , and These are respectively represented as empirical coefficients; The calculation of permeability and rock mass deformation characteristics is as follows: ; in, This is represented by the permeability of the fault zone, reflecting the seepage characteristics; It is expressed as mud loss, reflecting the permeability of the fault zone; This is expressed as the borehole trajectory offset, reflecting the degree of rock mass deformation; It is expressed as a natural gamma anomaly, reflecting lithological anomalies; , and These are respectively represented as empirical coefficients.

[0014] As a further improvement to this application, the calculation of the fault conditions in the borehole rock mass is as follows: ; in, This is expressed as the probability of fault existence, used to quantify the identification results of fault zones; It is expressed as a natural gamma anomaly, reflecting lithological anomalies; This is represented by the permeability of the fault zone, reflecting the seepage characteristics; and These are respectively represented as weighting coefficients.

[0015] As a further improvement to this application, the formula for calculating the borehole trajectory using the mean angle total range method is as follows: ; in, , , These are respectively represented by the nth measuring point. Axial displacement, Axial displacement and Axial displacement; , Represented as the first , Inclination angle of each measuring point; , Represented as the first , Azimuth angle of each measuring point; This is represented as the main design azimuth angle for drilling; Represented as the first The length of the borehole section, i.e., the measurement interval; The steps for calculating the accurate spatial parameters of a fault are as follows: Convert the spatial coordinates of borehole measuring points and fault anomaly points in the relative coordinate system to the fault spatial coordinate system values. Obtain the elevation of the opening point from the engineering plan. The following formula is used to calculate the relative coordinate values ​​of different measuring points and geological anomaly points in the exploratory directional borehole. Convert axial displacement to elevation; ; in, Represented as the directional drilling number Elevation of each measuring point; This is represented as the elevation of the hole opening point; Represented as the first Each measuring point Axial displacement; In the Gaussian plane coordinate system, the central meridian is the true north direction line, while the main design azimuth and measured borehole azimuth angle in the relative coordinate system are both magnetic azimuth. There is an angle between the true north direction line and the magnetic north direction line, namely magnetic declination. When converting the borehole relative coordinates to the mine plane coordinates, the magnetic azimuth needs to be corrected and converted into the true azimuth angle. The conversion relationship between the two is shown in the following formula: ; in, It is expressed as the borehole azimuth with true north as the direction of true north; It is expressed as the borehole azimuth with magnetic north as the true north direction; It is expressed as magnetic declination, with positive values ​​for east magnetic declination and negative values ​​for west magnetic declination; The angle between the mine's Gaussian plane coordinate system and the borehole's relative coordinate system is... ; Calculation formula as follows

[0016] in, It is expressed as the angle between the mine's Gaussian plane coordinate system and the borehole's relative coordinate system; According to Euler's theorem, the transformation relationship between the Gaussian plane coordinate system and the relative coordinate system of directional drilling involves one rotation and one translation. The transformation relationship between the Gaussian plane coordinate values ​​and the relative coordinate values ​​of directional drilling is as follows: ; in, Represented as an eastward offset value; Represented as northward deviation; This is expressed as the eastward offset of the opening point; This is expressed as the northward deviation of the aperture point; Obtain the eastward offset of the opening point from the engineering plan. , north bias value By using the transformation formula between the relative coordinate system and the plane coordinate system of the exploratory directional borehole, the relative coordinate values ​​of the borehole measuring points and geological anomalies are converted into... Axial displacement and The axial displacement is converted into planar coordinate values, namely eastward and northward offset values, and then drawn and displayed on the engineering plan.

[0017] The refined riverbed fault exploration system based on directional borehole group collaborative detection includes a data acquisition module, a data supplementation module, a directional borehole layout module, a drilling multi-parameter monitoring module, a fault spatial positioning module, and a fault gouge fine dating module. The data acquisition module is used to acquire digital topographic maps and geological structure data of riverbed faults along the river, and to construct three-dimensional geological images through data fusion algorithms. The data supplementation module is used to supplement and map active faults with surface outcrops through field geological surveys, and to improve the three-dimensional geological image by combining concealed fault detection technology. The directional drilling layout module is used to set the positions of the borehole opening and target points based on the three-dimensional geological image, and to design the directional drilling point, directional drilling intensity and borehole profile trajectory. The multi-parameter monitoring module during drilling is used to collect parameters such as drilling pressure fluctuation frequency, natural gamma value, mud loss and borehole trajectory offset in real time, and to calculate the fault situation of the rock mass in the borehole through a mathematical model. The fault spatial positioning module is used to measure the directional drilling trajectory parameters in real time, and to determine the type of geological anomaly points by combining fault identification features, and to calculate the spatial coordinate parameters of the fault. The fault gouge fine dating module is used to perform stratification processing on the fault gouge obtained by directional drilling and to collect dating samples for high-precision dating analysis.

[0018] The beneficial effects of this invention are: This invention uses a UAV multispectral camera to acquire data, combined with geological drilling to obtain fault mud particle size, sorting coefficient, and fracture parameters, achieving simultaneous analysis of surface morphology and underground structure. Simultaneously, through remote sensing image processing, grayscale enhancement, and topographic map fusion, a high-resolution three-dimensional geological image is constructed, laying a solid foundation for subsequent analysis. A weighted fusion model of lithological anomaly elevation variation and fracture connectivity parameters is introduced, combined with finite element simulation of the coupling effect of fracture network and lithological distribution, to generate a fault model with spatial three-dimensional characteristics. By designing borehole trajectories perpendicular to or intersecting the fault at large angles, and combining high-strength wireline coring tools and artificial directional drilling tools, stability and safety during drilling are ensured. For curved sections, flexible directional coring tools and drilling-while-guided directional correction technology are used to achieve continuous coring on complex paths, avoiding the high risks and low efficiency of traditional drilling methods that require frequent adjustments or blasting operations. The drilling-while-measuring system acquires trajectory parameters in real time, and combined with magnetic declination correction and coordinate transformation technology, the spatial coordinates of the fault are accurately calculated. By comparing and analyzing parameters such as drill pressure fluctuation frequency and natural gamma value with existing geological data, the state of the rock mass inside the borehole is fed back in real time. Combined with spatial coordinate correction of geological anomalies, the probability of fault existence, permeability, and rock mass deformation characteristics are accurately determined, significantly improving the scientific rigor and reliability of fault identification. By integrating multi-source data such as lithological anomaly elevation changes, fracture connectivity, and fault gouge grain size parameters, a comprehensive three-dimensional geological model is constructed. The fault gouge is layered and dating samples are collected. High-precision dating analysis is used to determine the age of fault activity, providing a scientific basis for the delineation of engineering avoidance areas. Compared with traditional methods, the comprehensive model quantifies the probability of fault existence and dynamic response characteristics, significantly reducing exploration costs and construction cycle, while enhancing the ability to predict geological hazards, resulting in three-dimensional and refined exploration results. Compared to traditional methods such as underwater drilling, horizontal tunnels across rivers, or paired inclined boreholes across rivers, this invention has significant advantages in terms of safety risks, implementation efficiency, cost control, and three-dimensional spatial deployment capabilities. This invention not only overcomes the limitations of traditional two-dimensional interpretation but also quantifies the permeability and rock deformation characteristics of fault zones through parameter linkage analysis, providing dynamic data support for fault activity assessment. Furthermore, through coordinated operation of directional borehole groups, exploration tasks can be completed on one side, avoiding the high investment and high difficulty of construction under complex terrain conditions. Ultimately, this invention achieves a comprehensive understanding of fault zones, providing reliable and efficient decision support for geological disaster prevention and engineering planning. Attached Figure Description

[0019] Figure 1 This is a schematic diagram of the steps in the method for refined exploration of riverbed faults along the river direction based on the collaborative detection of directional borehole groups in this application. Figure 2 This is a schematic diagram illustrating the specific steps of borehole layout and exploration in the riverbed longitudinal fault refinement method based on directional borehole group collaborative detection in this application. Figure 3 This is a planar schematic diagram showing the conversion of spatial coordinate values ​​in the relative coordinate system to fault spatial coordinate values ​​in the riverbed longitudinal fault refinement exploration method based on directional borehole group collaborative detection in this application; Figure 4 This is a schematic diagram illustrating the conversion between relative borehole coordinates and planar coordinates in the method for refined exploration of riverbed faults based on directional borehole group collaborative detection in this application. Figure 5 This is a schematic diagram of the pre-selected trench points for the refined exploration method of riverbed faults based on the collaborative detection of directional borehole groups in this application; Figure 6 This is a schematic diagram of the directional drilling structure for the refined exploration method of riverbed faults based on the collaborative detection of directional borehole groups in this application. Figure 7 This is a schematic diagram of the directional borehole exploration fault principle of the riverbed longitudinal fault refinement method based on the collaborative exploration of directional borehole groups in this application. Figure 8 This is a schematic diagram of the structure of the riverbed longitudinal fault refinement exploration system based on directional borehole group collaborative detection, which is the subject of this application.

[0020] In the diagram: 1. Main hole of directional drilling; 11. Inclined section of directional drilling; 12. Curved section of directional drilling; 13. Horizontal section of directional drilling; 14. Branch hole of directional drilling; 2. Directional drilling rig; 3. Fault. Detailed Implementation

[0021] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of this application, and not all of the embodiments. Based on the embodiments of this application, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of this application.

[0022] like Figure 1-7 As shown, this embodiment provides a method for refined exploration of riverbed faults along the river based on coordinated detection of directional borehole groups, including the following steps: S1. Obtain riverbed fault data: Collect digital topographic maps and geological structure data of riverbed faults along the river, and construct a three-dimensional image based on the collected riverbed fault data along the river. In this embodiment, preferably, the riverbed fault data along the river direction in S1 is used to construct a three-dimensional image: High-resolution digital topographic data were acquired using a drone equipped with a multispectral camera. ; Riverbed fault samples were obtained through geological drilling. The fracture density and lithological assemblage of the fault samples were analyzed to obtain the particle size data of the fault gouge. With sorting coefficient and extracting crack length and opening degree ; Through crack length and opening degree Calculate the connectivity of 3D crack network data ; Then, a weighted average method was used to assess connectivity. Particle size data With sorting coefficient The parameters of the fracture particle size are fused together to generate the comprehensive fracture particle size parameters of the fault gouge; Finally, the comprehensive fracture particle size parameters of the fault gouge were compared with high-resolution digital topographic map data. By integrating the fault data along the riverbed, a three-dimensional image is constructed. Nonlinear correlation model between lithology distribution and topography ; in, It is expressed as the change in elevation of lithological anomalies, used to quantify the correlation between lithology and topography; Elevation values, represented as digital topographic maps, reflect the landform. It is expressed as a particle size sorting coefficient, reflecting the depositional environment of fault gouge; and Represented as empirical coefficients, determined through inversion of historical data; Weighted average model of crack connectivity and particle size sorting coefficient ; in, Represented as comprehensive fracture parameters, used to quantify the permeability characteristics of fault zones; This is represented by fracture connectivity, reflecting the seepage capacity of the fault zone; It is expressed as a particle size sorting coefficient, reflecting the depositional environment of fault gouge; and These are respectively represented as weighting coefficients, determined through inversion of historical data; By combining the comprehensive fracture parameters with the lithological anomaly elevation variation of the digital topographic map, a three-dimensional fracture network model of the fault zone is generated. A three-dimensional geological image is generated by simulating the coupling effect between fracture network and lithological distribution using finite element method software.

[0023] It should be noted that, firstly, the detection range must be determined. The detection range of a single active fault is 2km-4km on both sides of the target fault. The active fault detection target area refers to the area where active fault investigation and exploration are carried out, and its side length should not be less than 25km. The detection area refers to the working range used to evaluate the seismic activity level and seismic tectonic environment of the area, with the target area as the center and a side length of not less than 150km. Interpretation of high-resolution digital topographic map data acquired by UAV-mounted multispectral cameras on major faults in the detection or target area; Compile a 1:250,000 seismic tectonic map of the exploration area; Compile a 1:50,000 map of active fault distribution in the target area; And the processing of fault data: Gaussian filtering is applied to digital topographic maps for noise reduction, with a filtering radius of 1-5m. The remote sensing images were converted to grayscale images, and histogram equalization was used to enhance the contrast. Grain size analysis was performed on core samples based on geological structural data, and the grain size distribution was determined using a laser particle size analyzer. The particle size distribution of fault gouge was determined using a laser particle size analyzer, and its particle size data were calculated. With sorting coefficient ; A three-dimensional crack network model of the trench area was obtained using a CT scanner, and the crack length was extracted. and opening degree And calculate the connectivity of the three-dimensional crack network data. ; ;in, Represented as crack connectivity, Represented as the first Crack length, Represented as the first Crack opening This represents the total number of cracks; Image processing algorithms are used to extract crack features from trench images to generate crack distribution maps; The weighted average method was used to assess crack connectivity. With particle size sorting coefficient The parameters are then fused to generate comprehensive crack parameters.

[0024] Alternatively, high-precision DEM (centimeter-level) data can be obtained through high-precision aerial satellite imagery (sub-meter level) and UAV aerial surveying, and then the target area and its surrounding area can be finely interpreted; the following steps are detailed: Remote sensing data processing: Using GF-7 high-resolution satellite imagery data of the target fracture, atmospheric correction, filtering, enhancement, geocoding, and cropping are performed through IHS transformation to form a target fracture strip image map; Extraction of active fault information: Digital image processing technology is used to analyze the spatial distribution, geometric structure, tectonic landforms, fault zone intersections and other macroscopic features of active faults in the target area, and to study other anomaly information and secondary feature information closely related to active faults. Production and interpretation of remote sensing images of the target area: The 0.6m panchromatic band and 2.5m multispectral band of the GF-7 satellite are fused to obtain color remote sensing images of the target area; combined with 1:50,000 topographic map data, remote sensing image maps (1:50,000) are compiled; based on this, combined with aerial photographs, interpretation maps of inferred (hidden) active faults are given, with a positioning accuracy of 10-20m; UAV aerial survey and high-precision DEM extraction of suspicious fault tracks: UAV aerial survey is used to obtain (centimeter-level) high-precision DEM data of suspicious fault tracks discovered by remote sensing interpretation. The data is then interpreted in detail to provide interpretation maps of inferred (hidden) active faults in key areas, with a positioning accuracy of 1-2m. During image interpretation, the interpretation results are verified in the field to ensure the quality of remote sensing interpretation.

[0025] S2. Supplement the collected data: Through field geological surveys, supplement the mapping of active faults with surface outcrops and detect hidden active faults to improve the three-dimensional image; The S2 process involves mapping active faults exposed on the surface through field geological surveys. The mapping elements include fault type, geomorphological elements, stratigraphic elements, igneous rock elements, and displacement. Furthermore, active faults exposed on the surface or concealed active faults with upper fault points shallower than 8m are detected. The active fault identification trench should span the entire fault zone. It should be noted that by using field geological surveys and concealed fault detection technology, the integrity and accuracy of three-dimensional geological images are significantly improved, while reducing exploration costs and time, providing reliable data support for dynamic response analysis of fault zones and prevention and control of geological disasters.

[0026] Furthermore, shallow seismic exploration is introduced for the exploration of concealed active faults with upper fault points buried at depths ranging from several meters to hundreds of meters. Faults on seismic profiles generally exhibit characteristics such as dislocation, bifurcation and merging, and strong phase conversion of the phase axis of reflected waves. The reflected waves at the fault points are disordered, and diffraction waves are easily formed at the fault points. The seismic profile of the seismic survey line can be analyzed by measuring the fault displacement, upper fault burial depth, apparent dip, and apparent dip angle. Several shallow seismic reflection wave geophysical profiles were arranged along the strike perpendicular to the concealed active fault to be detected, and the geophysical probes were interpreted. Then, based on the interpretation results, the suspected faults were numbered and the strike azimuth and dip angle of the suspected faults were determined. The inferred concealed fault is analyzed and compared with the geophysical exploration interpretation results to determine whether there are geophysical exploration interpretation results. If there are geophysical exploration interpretation results, proceed to step S3.

[0027] S3. Directional drilling layout and exploration: Based on the three-dimensional image, set the position of the opening point and target point, design the directional drilling point and directional drilling intensity, draw the borehole profile trajectory, use high-strength wireline coring drill rod and wireline coring tool for drilling feed, and use artificial directional drilling tools to force the borehole axis to bend and extend according to the designed trajectory. It should be noted that the borehole structure should be designed based on the borehole trajectory design, site and engineering geological conditions, drilling equipment, drilling methods and processes, final borehole diameter, type and method of directional drilling tools, in-hole tests and measurements, etc. The specific steps for borehole layout and exploration in S3 are as follows: S301: Select the borehole trajectory in the 3D image, design the directional drilling point and directional drilling intensity based on the location of the borehole opening point and target point, and draw the borehole profile trajectory; design the borehole structure based on the borehole trajectory design, site and engineering geological conditions, drilling equipment, drilling methods and processes, final borehole diameter, directional drilling tool type and method, and in-hole tests and inspections. It should be noted that the borehole trajectory should be perpendicular to or intersect at a large angle with the strike of the geophysically inferred fault; the borehole trajectory should pass through faults clearly shown by geophysical exploration and with obvious vertical displacement; the final depth of the directional borehole in the vertical direction should not be less than 10 m below the burial depth of the upper fault given by geophysical exploration, and greater than the burial depth of the lower boundary of the Upper Pleistocene; if the upper fault given by geophysical exploration results is located in the lower part of the Upper Pleistocene or the upper part of the Middle Pleistocene, the final depth of the directional borehole in the vertical direction should be greater than the burial depth of the lower boundary of the Upper Pleistocene; the curvature of the directional borehole curve segment should ensure the safety of raising and lowering the drill string and drilling, that is, it should be able to pass smoothly through the large-diameter drill string, and the drill string should not break due to excessive borehole curvature. S302: Directional drilling equipment and tools include drilling rigs, flushing fluid equipment, drilling tools, measuring and control instruments, and auxiliary tools; It should be noted that, for directional drilling, the drilling tools should preferably be a combination of "full-end drill bit, bent screw motor, non-magnetic drill collar and wireline drill pipe" or "core drilling tool, bent screw motor, non-magnetic drill collar and wireline drill pipe"; for core drilling, the drilling tools should preferably be a combination of "core drill bit, wireline core drilling tool, hydraulic impactor, and wireline drill pipe"; the directional drilling tools should preferably include types such as eccentric wedges, continuous directional drilling tools, and screw drills. S303: Securely install directional drilling equipment and tools; S304: High-strength wireline coring drill rods and wireline coring tools are used. The high-strength wireline coring drill rods and wireline coring tools use tapered guide coring bits. When drilling curved holes, the changes in the drill torque should be observed at any time. If the torque changes significantly, the drilling pressure should be reduced appropriately or the drill tool should be moved. After the torque returns to normal, coring should continue. If the torque is still abnormal, the drill should be lifted for inspection. S305: Drilling trajectory refers to the change in the spatial position of each point on the drilling axis, characterized by spatial elements such as hole depth, inclination angle, azimuth angle, elevation, horizontal length, and offset. Directional drilling trajectory uses artificial skew-making tools to force the drilling axis to bend and extend according to the designed trajectory. S306: After core sampling, borehole flushing and wall sealing are carried out, and accident prevention and handling are also carried out. S307: Continuous coring in directional drilling, including coring of inclined sections, coring of curved sections, and coring of horizontal sections; It should be noted that flexible directional coring tools can be used to achieve continuous coring in curved sections for core sampling in curved holes; when the core sampling trajectory deviates from the design trajectory, cabled / uncabled drilling directional technology can be used to correct the deviation; when the borehole trajectory reaches the design trajectory, wireline coring drill pipe can be used for continuous coring; core drilling in curved holes can be powered by the surface, the bottom of the hole, or both simultaneously; high-strength and high-toughness wireline coring drill pipe and drilling tools are used for core sampling in curved holes.

[0028] The steps for designing the trajectory in S3 are as follows: The spatial trajectory parameters of directional drilling can be calculated from three basic parameters: hole depth, dip angle, and azimuth angle. The hole depth is obtained by the drill rod accumulation method, while the dip angle and azimuth angle are measured in real time by the drilling measurement system during the drilling process. With the hole opening point as the origin, the positive X-axis direction is the extension direction of the main borehole orientation line, the positive Y-axis direction is rotated 90° horizontally clockwise, and the positive Z-axis direction is vertically upward. Using the basic parameters obtained from the measurement while drilling system, the borehole trajectory is calculated using the mean angle total distance method. S4. Multi-parameter monitoring while drilling: The drilling measurement system is used to collect parameters such as drilling pressure fluctuation frequency, natural gamma value, mud loss, and borehole trajectory deviation in real time, and to calculate the fault conditions of the rock mass in the borehole. The specific steps for analyzing the fault in the rock mass within the borehole in S4 are as follows: Deploy a measurement-while-drilling system to collect real-time data on drill pressure fluctuation frequency, natural gamma value, mud loss, and borehole trajectory deviation. The dominant frequency component of the drilling pressure fluctuation frequency is extracted by Fourier transform and used to determine the dynamic response characteristics of the fault zone. The lithological anomaly index of the fault zone was calculated by using correlation analysis between natural gamma values ​​and lithological combination data. By analyzing the correlation between mud loss and borehole trajectory deviation, the permeability of the fault zone and the deformation characteristics of the rock mass are quantified. Input the above parameters into the mathematical model to calculate the fault situation of the rock mass inside the borehole; It should be noted that the table summarizing the acquisition parameters and fault response characteristics is included.

[0029] The lithological anomaly index of the fault zone is calculated as follows: ; in, It is expressed as a natural gamma anomaly, used to quantify the lithological anomaly characteristics of fault zones; The natural gamma value of the homogeneous region is used as a baseline value. It is represented as the dominant frequency component of the drilling pressure fluctuation frequency, reflecting the dynamic response characteristics of the fault zone; It is expressed as the mineral percentage, reflecting the compositional characteristics of fault gouge; , and These are respectively represented as empirical coefficients; The calculation of permeability and rock mass deformation characteristics is as follows: ; in, This is represented by the permeability of the fault zone, reflecting the seepage characteristics; It is expressed as mud loss, reflecting the permeability of the fault zone; This is expressed as the borehole trajectory offset, reflecting the degree of rock mass deformation; It is expressed as a natural gamma anomaly, reflecting lithological anomalies; , and These are respectively represented as empirical coefficients.

[0030] The calculation of the fault conditions in the rock mass within the borehole is as follows: ; in, This is expressed as the probability of fault existence, used to quantify the identification results of fault zones; It is expressed as a natural gamma anomaly, reflecting lithological anomalies; This is represented by the permeability of the fault zone, reflecting the seepage characteristics; and These are respectively represented as weighting coefficients.

[0031] S5. Fault spatial positioning: During the directional drilling process, its spatial trajectory parameters are measured in real time, and the drilling geological anomaly points and geological anomaly body types are determined based on the fault identification characteristics. After obtaining the spatial coordinates of each geological anomaly point from the directional drilling trajectory parameters, the accurate spatial parameters of the fault are calculated, and the fault along the riverbed is drilled. The formula for calculating the borehole trajectory using the mean angle total range method is as follows: ; in, , , These are respectively represented as the nth measuring point. Axial displacement, Axial displacement and Axial displacement; , Represented as the first , Inclination angle of each measuring point; , Represented as the first , Azimuth angle of each measuring point; This is represented as the main design azimuth angle for drilling; Represented as the first The length of the borehole segment, i.e., the measurement interval; The steps for calculating the accurate spatial parameters of a fault are as follows: Convert the spatial coordinates of borehole measuring points and fault anomaly points in the relative coordinate system to the fault spatial coordinate system values. Obtain the elevation of the opening point from the engineering plan. The following formula is used to calculate the relative coordinate values ​​of different measuring points and geological anomaly points in the exploratory directional borehole. Convert axial displacement to elevation; ; in, Represented as the directional drilling number Elevation of each measuring point; This is represented as the elevation of the hole opening point; Represented as the first Each measuring point Axial displacement; In the Gaussian plane coordinate system, the central meridian is the true north direction line, while the main design azimuth and measured borehole azimuth angle in the relative coordinate system are both magnetic azimuth. There is an angle between the true north direction line and the magnetic north direction line, namely magnetic declination. When converting the borehole relative coordinates to the mine plane coordinates, the magnetic azimuth needs to be corrected and converted into the true azimuth angle. The conversion relationship between the two is shown in the following formula: ; in, It is expressed as the borehole azimuth with true north as the direction of true north; It is expressed as the borehole azimuth with magnetic north as the true north direction; It is expressed as magnetic declination, with positive values ​​for east magnetic declination and negative values ​​for west magnetic declination; The angle between the mine's Gaussian plane coordinate system and the borehole's relative coordinate system is... ; Calculation formula as follows

[0032] in, It is expressed as the angle between the mine's Gaussian plane coordinate system and the borehole's relative coordinate system; According to Euler's theorem, the transformation relationship between the Gaussian plane coordinate system and the relative coordinate system of directional drilling involves one rotation and one translation. The transformation relationship between the Gaussian plane coordinate values ​​and the relative coordinate values ​​of directional drilling is as follows: ; in, Represented as an eastward offset value; Represented as northward deviation; This is expressed as the eastward offset of the opening point; This is expressed as the northward deviation of the aperture point; Obtain the eastward offset of the opening point from the engineering plan. , north bias value By using the transformation formula between the relative coordinate system and the plane coordinate system of the exploratory directional borehole, the relative coordinate values ​​of the borehole measuring points and geological anomalies are converted into... Axial displacement and The axial displacement is converted into planar coordinate values, namely eastward and northward deviations, and then drawn and displayed on the engineering plan. Based on the exploratory directional borehole trajectory, spatial data of geological anomalies encountered during drilling, existing borehole data, and data such as relevant stratigraphic ages and geophysical logging curves, a fault and exploratory directional borehole profile diagram is drawn. Among them, a and b are the intersections of the main directional borehole and the fault line, and c and d are the intersections of the branch directional boreholes and the fault.

[0033] In a specific embodiment, a shallow seismic profile is selected for directional drilling of the main borehole 1 (hole DXZK01) across fault 3. The directional drilling rig 2 is installed at the designated borehole location. After the borehole is opened and accepted, the coring of the inclined section 11, the curved section 12, and the horizontal section 13 of the directional borehole are completed to accurately locate the concealed fault and determine the spatial coordinates of the fault point and the fault activity. Based on the fault 3 revealed by the main borehole 1, the directional drilling branch borehole 14 (hole DXZK1-1) is arranged and continuous coring is completed.

[0034] Technical requirements for hole No. DXZK01

[0035] Technical requirements for hole No. DXZK01-1

[0036] S6. Fine dating of fault gouge: After finely stratifying the fault material on the fault plane along the riverbed through directional drilling, dating samples are collected and performed with high precision. Specific examples: The carbon-14 age of the breccia in the fracture zone is 51±3ka, which belongs to the Late Pleistocene activity. It is identified as a potential active fault, not Holocene active but with slow creep. According to the specifications, the engineering clearance width is recommended to be reduced from 30m to 15m. To more clearly illustrate the advantages of this invention compared to existing technologies such as underwater borehole exploration, river-crossing tunnels, and paired inclined borehole drilling across rivers, these technical solutions have been compared, and the comparison results are shown in the table below: Comparison of Options

[0037] As shown in the table above, compared with existing technologies such as underwater drilling exploration, river-crossing tunnels, and paired inclined borehole drilling across rivers, the present invention has lower safety risks, higher drilling efficiency, lower costs, stronger operability, and can reflect the three-dimensional spatial distribution characteristics of faults, forming a three-dimensional geological description.

[0038] refer to Figure 8A refined riverbed fault exploration system based on directional borehole group collaborative detection includes a data acquisition module, a data supplementation module, a directional borehole layout module, a multi-parameter monitoring module while drilling, a fault spatial positioning module, and a fault gouge fine dating module. The data acquisition module is used to acquire digital topographic maps and geological structure data of riverbed faults along the river, and to construct three-dimensional geological images through data fusion algorithms. The data supplementation module is used to supplement and map active faults with surface outcrops through field geological surveys, and to improve the three-dimensional geological image by combining concealed fault detection technology. The directional drilling layout module is used to set the positions of the borehole opening and target points based on the three-dimensional geological image, and to design the directional drilling point, directional drilling intensity and borehole profile trajectory. The multi-parameter monitoring module during drilling is used to collect parameters such as drilling pressure fluctuation frequency, natural gamma value, mud loss and borehole trajectory offset in real time, and to calculate the fault situation of the rock mass in the borehole through a mathematical model. The fault spatial positioning module is used to measure the directional drilling trajectory parameters in real time, and to determine the type of geological anomaly points by combining fault identification features, and to calculate the spatial coordinate parameters of the fault. The fault gouge fine dating module is used to perform stratification processing on the fault gouge obtained by directional drilling and to collect dating samples for high-precision dating analysis.

[0039] Furthermore, the storage medium in this application embodiment stores program instructions capable of implementing all the above methods. These program instructions can be stored in the storage medium in the form of a software product, including several instructions to cause a computer device (which may be a personal computer, server, or network device, etc.) or processor to execute all or part of the steps of the methods described in the various embodiments of this application. The aforementioned storage medium includes various media capable of storing program code, such as USB flash drives, portable hard drives, read-only memory (ROM), random access memory (RAM), magnetic disks, or optical disks, or terminal devices such as computers, servers, mobile phones, and tablets.

[0040] In the several embodiments provided in this application, it should be understood that the disclosed systems, apparatuses, and methods can be implemented in other ways. For example, the apparatus embodiments described above are merely illustrative; for instance, the division of units is only a logical functional division, and in actual implementation, there may be other division methods. For example, multiple units or components may be combined or integrated into another system, or some features may be ignored or not executed. Furthermore, the coupling or direct coupling or communication connection shown or discussed may be through some interfaces, or indirect coupling or communication connection between apparatuses or units, and may be electrical, mechanical, or other forms.

[0041] Furthermore, the functional units in the various embodiments of this application can be integrated into one processing unit, or each unit can exist physically separately, or two or more units can be integrated into one unit. The integrated units described above can be implemented in hardware or as software functional units. The above are merely embodiments of this application and do not limit the patent scope of this application. Any equivalent structural or procedural transformations made based on the description and drawings of this application, or direct or indirect applications in other related technical fields, are similarly included within the patent protection scope of this application.

[0042] The specific embodiments of the invention have been described in detail above, but they are only examples, and this application is not limited to the specific embodiments described above. For those skilled in the art, any equivalent modifications or substitutions to the invention are also within the scope of this application. Therefore, all equivalent changes, modifications, and improvements made without departing from the spirit and principles of this application should be covered within the scope of this application.

Claims

1. A method for refined exploration of riverbed faults along the river based on coordinated directional borehole drilling, characterized in that, It includes the following steps: S1. Obtain riverbed fault data: Collect digital topographic maps and geological structure data of riverbed faults along the river, and construct a three-dimensional image based on the collected riverbed fault data along the river. S2. Supplement the collected data: Through field geological surveys, supplement the mapping of active faults with surface outcrops and detect hidden active faults to improve the three-dimensional image; S3. Directional drilling layout and exploration: Based on the three-dimensional image, set the position of the opening point and target point, design the directional drilling point and directional drilling intensity, draw the borehole profile trajectory, use high-strength wireline coring drill rod and wireline coring tool for drilling feed, and use artificial directional drilling tools to force the borehole axis to bend and extend according to the designed trajectory. S4. Multi-parameter monitoring while drilling: The drilling measurement system is used to collect parameters such as drilling pressure fluctuation frequency, natural gamma value, mud loss, and borehole trajectory deviation in real time, and to calculate the fault conditions of the rock mass in the borehole. S5. Fault spatial positioning: During the directional drilling process, its spatial trajectory parameters are measured in real time, and the drilling geological anomaly points and geological anomaly body types are determined based on the fault identification characteristics. After obtaining the spatial coordinates of each geological anomaly point from the directional drilling trajectory parameters, the accurate spatial parameters of the fault are calculated, and the fault along the riverbed is drilled. S6. Fine dating of fault gouge: After directional drilling of fault material along the riverbed, finely stratify the fault material and collect dating samples for high-precision dating.

2. The method for refined exploration of riverbed faults along the riverbank based on coordinated directional borehole group detection according to claim 1, characterized in that, The riverbed fault data along the river in S1 are used to construct a three-dimensional image: High-resolution digital topographic data were acquired using a drone equipped with a multispectral camera. ; Riverbed fault samples were obtained through geological drilling. The fracture density and lithological assemblage of the fault samples were analyzed to obtain the particle size data of the fault gouge. With sorting coefficient and extracting crack length and opening degree ; By crack length and opening degree Calculate the connectivity of 3D crack network data ; Then, a weighted average method was used to assess connectivity. Particle size data With sorting coefficient The parameters of the fracture particle size are fused together to generate the comprehensive fracture particle size parameters of the fault gouge; Finally, the comprehensive fracture particle size parameters of the fault gouge were compared with high-resolution digital topographic map data. By integrating the fault data along the riverbed, a three-dimensional image is constructed.

3. The method for refined exploration of riverbed faults along the riverbank based on coordinated directional borehole group detection according to claim 1, characterized in that, The S2 process involves mapping active faults exposed on the surface through field geological surveys. The mapping elements include fault type, geomorphological features, stratigraphic features, igneous rock features, and displacement. Furthermore, active faults exposed on the surface or concealed active faults with upper fault points shallower than 8m are detected. The active fault identification trench should span the entire fault zone.

4. The method for refined exploration of riverbed faults along the river direction based on coordinated directional borehole group detection according to claim 3, characterized in that, The specific steps for borehole layout and exploration in S3 are as follows: S301: Select the borehole trajectory in the 3D image, design the directional drilling point and directional drilling intensity based on the location of the borehole opening point and target point, and draw the borehole profile trajectory; design the borehole structure based on the borehole trajectory design, site and engineering geological conditions, drilling equipment, drilling methods and processes, final borehole diameter, directional drilling tool type and method, and in-hole tests and inspections. S302: Directional drilling equipment and tools include drilling rigs, flushing fluid equipment, drilling tools, measuring and control instruments, and auxiliary tools; S303: Securely install directional drilling equipment and tools; S304: High-strength wireline coring drill rods and wireline coring tools are used. The high-strength wireline coring drill rods and wireline coring tools use tapered guide coring bits. When drilling curved holes, the changes in the drill torque should be observed at any time. If the torque changes significantly, the drilling pressure should be reduced appropriately or the drill tool should be moved. After the torque returns to normal, coring should continue. If the torque is still abnormal, the drill should be lifted for inspection. S305: Drilling trajectory refers to the change in the spatial position of each point on the drilling axis, characterized by spatial elements such as hole depth, inclination angle, azimuth angle, elevation, horizontal length, and offset. Directional drilling trajectory uses artificial skew-making tools to force the drilling axis to bend and extend according to the designed trajectory. S306: After core sampling, borehole flushing and wall sealing are carried out, and accident prevention and handling are also carried out. S307: Continuous coring in directional drilling, including coring in inclined sections, coring in curved sections, and coring in horizontal sections.

5. The method for refined exploration of riverbed faults along the riverbank based on coordinated directional borehole group detection according to claim 4, characterized in that, The steps for designing the trajectory in S3 are as follows: The spatial trajectory parameters of directional drilling can be calculated from three basic parameters: hole depth, dip angle, and azimuth angle. The hole depth is obtained by the drill rod accumulation method, while the dip angle and azimuth angle are measured in real time by the drilling measurement system during the drilling process. With the hole opening point as the origin, the positive X-axis direction is the extension direction of the main borehole orientation line, the positive Y-axis direction is rotated 90° clockwise around the X-axis, and the positive Z-axis direction is vertically upward. Using the basic parameters obtained from the measurement while drilling system, the borehole trajectory is calculated using the mean angle total distance method.

6. The method for refined exploration of riverbed faults along the river direction based on coordinated directional borehole group detection according to claim 4, characterized in that, The specific steps for analyzing the fault in the rock mass within the borehole in S4 are as follows: Deploy a drilling measurement system to collect real-time data on drill pressure fluctuation frequency, natural gamma value, mud loss, and borehole trajectory deviation. The dominant frequency component of the drilling pressure fluctuation frequency is extracted by Fourier transform and used to determine the dynamic response characteristics of the fault zone. The lithological anomaly index of the fault zone was calculated by using correlation analysis between natural gamma values ​​and lithological combination data. By analyzing the correlation between mud loss and borehole trajectory deviation, the permeability of the fault zone and the deformation characteristics of the rock mass are quantified. Input the above parameters into the mathematical model to calculate the fault conditions of the rock mass inside the borehole.

7. The method for refined exploration of riverbed faults along the riverbank based on coordinated directional borehole group detection according to claim 6, characterized in that, The lithological anomaly index of the fault zone is calculated as follows: ； in, It is expressed as a natural gamma anomaly, used to quantify the lithological anomaly characteristics of fault zones; The natural gamma value of the homogeneous region is used as a baseline value. It is represented as the dominant frequency component of the drilling pressure fluctuation frequency, reflecting the dynamic response characteristics of the fault zone; It is expressed as the mineral percentage, reflecting the compositional characteristics of fault gouge; , and These are respectively represented as empirical coefficients; The calculation of permeability and rock mass deformation characteristics is as follows: ； in, This is represented by the permeability of the fault zone, reflecting the seepage characteristics; It is expressed as mud loss, reflecting the permeability of the fault zone; This is expressed as the borehole trajectory offset, reflecting the degree of rock mass deformation; It is expressed as a natural gamma anomaly, reflecting lithological anomalies; , and These are respectively represented as empirical coefficients.

8. The method for refined exploration of riverbed faults along the river direction based on coordinated directional borehole group detection according to claim 6, characterized in that, The calculation of the fault conditions in the rock mass within the borehole is as follows: ； in, This is expressed as the probability of fault existence, used to quantify the identification results of fault zones; It is expressed as a natural gamma anomaly, reflecting lithological anomalies; This is represented by the permeability of the fault zone, reflecting the seepage characteristics; and These are respectively represented as weighting coefficients.

9. The method for refined exploration of riverbed faults along the river based on coordinated directional borehole group detection according to claim 5, characterized in that, The formula for calculating the borehole trajectory using the mean angle total range method is as follows: ； in, , , These are respectively represented as the nth measuring point. Axial displacement, Axial displacement and Axial displacement; , Represented as the first , Inclination angle of each measuring point; , Represented as the first , Azimuth angle of each measuring point; This is represented as the main design azimuth angle for drilling; Represented as the first The length of the borehole section, i.e., the measurement interval; The steps for calculating the accurate spatial parameters of a fault are as follows: Convert the spatial coordinates of borehole measuring points and fault anomaly points in the relative coordinate system to the fault spatial coordinate system values. Obtain the elevation of the opening point from the engineering plan. The following formula is used to calculate the relative coordinate values ​​of different measuring points and geological anomaly points in the exploratory directional borehole. Convert axial displacement to elevation; ； in, Represented as the directional drilling number Elevation of each measuring point; This is represented as the elevation of the hole opening point; Represented as the first Each measuring point Axial displacement; In the Gaussian plane coordinate system, the central meridian is the true north direction line, while the main design azimuth and measured borehole azimuth angle in the relative coordinate system are both magnetic azimuth. There is an angle between the true north direction line and the magnetic north direction line, namely magnetic declination. When converting the borehole relative coordinates to the mine plane coordinates, the magnetic azimuth needs to be corrected and converted into the true azimuth angle. The conversion relationship between the two is shown in the following formula: ； in, It is expressed as the borehole azimuth with true north as the direction of true north; It is expressed as the borehole azimuth with magnetic north as the true north direction; It is expressed as magnetic declination, with positive values ​​for east magnetic declination and negative values ​​for west magnetic declination; The angle between the mine's Gaussian plane coordinate system and the borehole's relative coordinate system is... ; Calculation formula as follows in, It is expressed as the angle between the mine's Gaussian plane coordinate system and the borehole's relative coordinate system; According to Euler's theorem, the transformation relationship between the Gaussian plane coordinate system and the relative coordinate system of directional drilling involves one rotation and one translation. The transformation relationship between the Gaussian plane coordinate values ​​and the relative coordinate values ​​of directional drilling is as follows: ； in, Represented as an eastward offset value; Represented as northward deviation; This is expressed as the eastward offset of the opening point; This is expressed as the northward deviation of the aperture point; Obtain the eastward offset of the opening point from the engineering plan. , north bias value By using the transformation formula between the relative coordinate system and the plane coordinate system of the exploratory directional borehole, the relative coordinate values ​​of the borehole measuring points and geological anomalies are converted into... Axial displacement and The axial displacement is converted into planar coordinate values, namely eastward and northward offset values, and then drawn and displayed on the engineering plan.

10. A refined riverbed fault exploration system based on directional borehole group collaborative detection, applied to the refined riverbed fault exploration method based on directional borehole group collaborative detection as described in any one of claims 1 to 9, characterized in that, It includes a data acquisition module, a data supplementation module, a directional drilling layout module, a multi-parameter monitoring module while drilling, a fault spatial positioning module, and a fault gouge fine dating module; The data acquisition module is used to acquire digital topographic maps and geological structure data of riverbed faults along the river, and to construct three-dimensional geological images through data fusion algorithms. The data supplementation module is used to supplement and map active faults with surface outcrops through field geological surveys, and to improve the three-dimensional geological image by combining concealed fault detection technology. The directional drilling layout module is used to set the positions of the borehole opening and target points based on the three-dimensional geological image, and to design the directional drilling point, directional drilling intensity and borehole profile trajectory. The multi-parameter monitoring module during drilling is used to collect parameters such as drilling pressure fluctuation frequency, natural gamma value, mud loss and borehole trajectory offset in real time, and to calculate the fault situation of the rock mass in the borehole through a mathematical model. The fault spatial positioning module is used to measure the directional drilling trajectory parameters in real time, and to determine the type of geological anomaly points by combining fault identification features, and to calculate the spatial coordinate parameters of the fault. The fault gouge fine dating module is used to perform stratification processing on the fault gouge obtained by directional drilling and to collect dating samples for high-precision dating analysis.

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