A method for detecting water-conducting fracture zones based on directional drilling detection technology

Abstract

The present invention relates to the technical field of coal mine safety detection, and specifically to a water-conducting fracture zone detection method based on directional drilling detection technology. The method includes: determining a single coal seam water-conducting fracture zone exploration area, a multi-coal seam water-conducting fracture zone exploration area, a single coal seam directional horizontal drilling area, and a multi-coal seam directional horizontal drilling area, and selecting a first surface drilling position and a second surface drilling position; drilling from the first surface drilling position and the second surface drilling position, setting a branch inclination point, drilling to the multi-coal seam water-conducting fracture zone exploration area for exploration; continuing to drill from the first surface drilling position and the second surface drilling position, setting a branch inclination point, drilling from the branch inclination point to the single coal seam water-conducting fracture zone exploration area for exploration; obtaining the fracture zone development conditions of the single coal seam water-conducting fracture zone exploration area and the multi-coal seam water-conducting fracture zone exploration area. The present invention can avoid the influence of the exploration position on the water-conducting fracture zone and improve the accuracy of exploration.

Description

Technical Field

[0001] The invention relates to the technical field of coal mine safety detection, and in particular to a water-conducting fracture zone detection method based on directional drilling detection technology. Background Art

[0002] Disasters such as gas, mine water and rock burst in coal mines restrict the safe mining of coal mines. Mine water includes roof water, floor water, surface water, goaf water and structural water. The five water hazards are closely hydraulically connected. Mine water flows into the mine through the water channel, threatening the safe mining of coal mines. Therefore, how to prevent and control mine water has become the main research issue in coal mines. As the water channel, the detection of water-conducting fracture zones is crucial.

[0003] At present, the observation methods of the height of the "two zones" are mainly divided into ground drilling observation method, underground drilling method, geophysical method, direct observation method of working face and observation method of internal tunnel of overburden damage zone. In the actual mining process, the observation of the height of the "two zones" is still mainly based on ground and underground drilling methods. In order to study the morphology of the "two zones" and the cracking and leakage characteristics of the mined rock mass and improve the accuracy of determining the height of the "two zones", it can be used in combination with borehole television and geophysical method. However, the direct observation method of the working face and the observation method of the internal tunnel of the overburden damage zone are rarely used at present because of certain safety hazards, large observation workload and strict conditions.

[0004] The exploration of water-conducting fracture zones is generally carried out with a double-ended water plug. The drilling holes are arranged at the position after the second cycle of pressure on the working face (generally more than 100m away from the opening of the cut hole, and the drilling holes are arranged at 5-20m in the return air lane and the transport lane). After drilling into a certain position, water injection is carried out. The height of the development of the water-conducting fracture zone is judged according to the water pressure and the size of the water flow. However, this method has certain defects. The measured data cannot truly reflect the actual height. The drilling position is limited to the actual situation of the mine working face. At the same time, the spatial morphology of the water-conducting fracture zone cannot be truly expressed. Summary of the invention

[0005] In order to solve the above technical problems, the purpose of the present invention is to provide a method for detecting water-conducting fracture zones based on directional drilling detection technology. The technical solutions adopted are as follows:

[0006] An embodiment of the present invention provides a method for detecting a water-conducting fracture zone based on a directional drilling detection technology, the method comprising:

[0007] Determine a single coal seam water-conducting fracture zone exploration area, a multi-coal seam water-conducting fracture zone exploration area, a single coal seam directional horizontal drilling area, and a multi-coal seam directional horizontal drilling area, and select surface drilling positions; the surface drilling positions include a first surface drilling position and a second surface drilling position;

[0008] Drilling is performed from a first surface drilling position and a second surface drilling position respectively to reach the multi-coal seam directional horizontal drilling area corresponding to the first surface drilling position and the second surface drilling position respectively, a branching deflection point is set in the multi-coal seam directional horizontal drilling area, and drilling is performed from the branching deflection point to reach the multi-coal seam water-conducting fracture zone exploration area for exploration;

[0009] Drilling from the multi-coal seam directional horizontal drilling areas corresponding to the first surface drilling position and the second surface drilling position respectively, reaching the single coal seam directional horizontal drilling areas corresponding to the first surface drilling position and the second surface drilling position respectively, setting a branch deflection point in the single coal seam directional horizontal drilling area, drilling from the branch deflection point to reach the single coal seam water-conducting fracture zone exploration area for exploration;

[0010] Obtain the fracture zone development conditions of single coal seam water-conducting fracture zone exploration areas and multi-coal seam water-conducting fracture zone exploration areas.

[0011] Preferably, determining the single coal seam water-conducting fracture zone exploration area and the multi-coal seam water-conducting fracture zone exploration area includes:

[0012] Obtain the estimated height of the single coal seam water-conducting fracture zone and the estimated height of the multi-coal seam water-conducting fracture zone of the working face to be tested; determine the single coal seam water-conducting fracture zone exploration area and the multi-coal seam water-conducting fracture zone exploration area respectively according to the estimated height of the single coal seam water-conducting fracture zone and the estimated height of the multi-coal seam water-conducting fracture zone.

[0013] Preferably, the single coal seam directional horizontal drilling area and the multi-coal seam directional horizontal drilling area include:

[0014] According to the single coal seam water-conducting fracture zone exploration area and the multi-coal seam water-conducting fracture zone exploration area, combined with the drilling data of the working face to be tested, the mining situation of the working face to be tested, the geological structure and the directional drilling water-vertical ratio, the single coal seam directional horizontal drilling area and the multi-coal seam directional horizontal drilling area are determined; there are two single coal seam directional horizontal drilling areas, and the two single coal seam directional horizontal drilling areas have different depths. The shallower one is recorded as the first single coal seam directional horizontal drilling area, and the deeper one is recorded as the second single coal seam directional horizontal drilling area; there are also two multi-coal seam directional horizontal drilling areas, and the two single coal seam directional horizontal drilling areas have different depths. The shallower one is recorded as the first multi-coal seam directional horizontal drilling area, and the deeper one is recorded as the second multi-coal seam directional horizontal drilling area.

[0015] Preferably, the surface drilling location includes:

[0016] Draw a straight line parallel to the return air chute at a set distance inside the inner wall of the downwind chute on the ground of the working face to be tested, and find a point on the straight line as the first surface drilling position. A point on the straight line to the south of the first surface drilling position and at a set distance from the first surface drilling position is the second surface drilling position.

[0017] Preferably, drilling from a first surface drilling position and a second surface drilling position respectively to reach a multi-coal seam directional horizontal drilling area comprises:

[0018] Vertical construction is carried out at the first surface drilling position and the second surface drilling position respectively to obtain directional main holes, which are recorded as the first main hole and the second main hole; the inclination point located in the first multi-coal seam directional horizontal drilling area is reached from the first main hole, and the inclination point located in the second multi-coal seam directional horizontal drilling area is reached from the second main hole.

[0019] Preferably, a branch deflection point is set in the multi-coal seam directional horizontal drilling area, and drilling is performed from the branch deflection point to reach the multi-coal seam water-conducting fracture zone exploration area for exploration, including:

[0020] Drill horizontally from the inclination point in the first multi-coal seam directional horizontal drilling area to the three branch inclination points set in the first multi-coal seam directional horizontal drilling area, and incline downward to the multi-coal seam detection terminal hole positions in the multi-coal seam water-conducting fracture zone exploration area, and detect the development height of the water-conducting fracture zone at a set distance inside the inner wall of the return air chute of the mining working face above the working face to be tested, a set distance inside the inner wall of the transport chute, and the center of the working face; drill horizontally from the inclination point in the second multi-coal seam directional horizontal drilling area to the three branch inclination points set in the second multi-coal seam directional horizontal drilling area, and incline downward to the multi-coal seam detection terminal hole positions in the multi-coal seam water-conducting fracture zone exploration area, and detect the development height of the water-conducting fracture zone at a set distance inside the inner wall of the return air chute of the mining working face above the working face to be tested, a set distance inside the inner wall of the transport chute, and the center of the working face.

[0021] Preferably, reaching the single coal seam directional horizontal drilling area corresponding to the first surface drilling position and the second surface drilling position respectively includes:

[0022] Drill downward from the inclination points in the first multi-coal seam directional horizontal drilling area and the second multi-coal seam directional horizontal drilling area respectively to reach the inclination point in the first single coal seam directional horizontal drilling area and the inclination point in the second single coal seam directional horizontal drilling area.

[0023] Preferably, a branch deflection point is set in the single coal seam directional horizontal drilling area, and drilling is performed from the branch deflection point to reach the single coal seam water-conducting fracture zone exploration area for exploration, including:

[0024] Drill horizontally from the inclining point in the first single coal seam directional horizontal drilling area to the three branch inclining points set in the first single coal seam directional horizontal drilling area, and incline downward to the single coal seam detection end hole position in the single coal seam water-conducting fracture zone exploration area, and detect the development height of the water-conducting fracture zone at a set distance inside the inner wall of the return air chute of the working face to be tested, a set distance inside the inner wall of the transport chute, and the center of the working face; drill horizontally from the inclining point in the second single coal seam directional horizontal drilling area to the three branch inclining points set in the second single coal seam directional horizontal drilling area, and incline downward to the single coal seam detection end hole position in the single coal seam water-conducting fracture zone exploration area, and detect the development height of the water-conducting fracture zone at a set distance inside the inner wall of the return air chute of the working face to be tested, a set distance inside the inner wall of the transport chute, and the center of the working face.

[0025] Preferably, obtaining the fracture zone development conditions of the single coal seam water-conducting fracture zone exploration area and the multi-coal seam water-conducting fracture zone exploration area includes:

[0026] In the process of drilling from the branch deflection point of the first multi-coal seam directional horizontal drilling area to the multi-coal seam water-conducting fracture zone exploration area, the development of longitudinal fractures in the multi-coal seam water-conducting fracture zone is determined based on the drilling slurry loss, borehole peep instrument and while-drilling gamma logging;

[0027] In the process of drilling from the branch deflection point of the second multi-coal seam directional horizontal drilling area to the multi-coal seam water-conducting fracture zone exploration area, the development of lateral fractures in the multi-coal seam water-conducting fracture zone is determined based on the drilling slurry loss, borehole peep instrument and while-drilling gamma logging;

[0028] In the process of drilling from the branch deflection point in the first single coal seam directional horizontal drilling area to the exploration area of ​​the single coal seam water-conducting fracture zone, the development of the longitudinal fractures in the single coal seam water-conducting fracture zone is determined based on the drilling slurry loss, the borehole peep instrument and the while-drilling gamma logging;

[0029] In the process of drilling from the branch deflection point in the second single coal seam directional horizontal drilling area to the exploration area of ​​the single coal seam water-conducting fracture zone, the development of lateral fractures in the single coal seam water-conducting fracture zone is determined based on the drilling slurry loss, borehole peep instrument and while-drilling gamma logging;

[0030] According to the development of longitudinal fractures in the multi-coal seam water-conducting fracture zones and the development of transverse fractures in the multi-coal seam water-conducting fracture zones, a full-time and space schematic diagram of the multi-coal seam water-conducting fracture zones is drawn to obtain the development of fracture zones in the exploration area of ​​the multi-coal seam water-conducting fracture zones;

[0031] According to the development of longitudinal fractures in the single coal seam water-conducting fracture zone and the development of transverse fractures in the single coal seam water-conducting fracture zone, a full-time and space schematic diagram of the single coal seam water-conducting fracture zone is drawn, and the development of the fracture zone in the exploration area of ​​the single coal seam water-conducting fracture zone is obtained.

[0032] The embodiments of the present invention have at least the following beneficial effects: the present invention determines a first surface drilling position and a second surface drilling position, and respectively drills into a single coal seam water-conducting fracture zone exploration area and a multi-coal seam water-conducting fracture zone exploration area from the first surface drilling position and the second surface drilling position for exploration, and explores toward a target layer (target point) from different opening positions, thereby solving the problem of incomplete detection of the spatial development of fractures and improving the accuracy and comprehensiveness of detection; at the same time, a branch inclination point is set in a multi-coal seam directional horizontal drilling area, and drilling is performed from the branch inclination point to reach the multi-coal seam water-conducting fracture zone exploration area for exploration, and in a single coal seam directional horizontal drilling area, a branch inclination point is set to drill into ... water-conducting fracture zone exploration area, a branch inclination point is set to drill into the multi-coal seam water-conducting fracture zone exploration area, and in a single coal seam water-conducting fracture zone exploration area, a branch inclination point is set to drill into the multi-coal seam water- Branch inclining points are set in the horizontal drilling area, and drilling is carried out from the branch inclining points to reach the single coal seam water-conducting fracture zone exploration area for exploration, which fully utilizes the advantages of directional drilling and makes up for the shortcomings of a single borehole in the detection process, thereby improving the detection performance. Through the detection of directional drilling, the overburden structure type of the mining area is effectively combined to further improve the detection accuracy; drilling is carried out from the first surface drilling position and the second surface drilling position to explore the single coal seam water-conducting fracture zone exploration area and the multi-coal seam water-conducting fracture zone exploration area, realizing multiple uses of one hole, and being able to simultaneously detect the development of a single coal seam fracture zone and the development of multiple coal seams fracture zone, thereby improving the exploration efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] In order to more clearly illustrate the technical solutions and advantages in the embodiments of the present invention or the prior art, the drawings required for use in the embodiments or the prior art descriptions are briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0034] Figure 1 A method flow chart of a water-conducting fracture zone detection method based on directional drilling detection technology provided by an embodiment of the present invention;

[0035] Figure 2 A schematic diagram of the drilling position of a method for detecting a water-conducting fracture zone based on directional drilling detection technology provided by an embodiment of the present invention;

[0036] Figure 3 A schematic diagram of a drilling trajectory of a water-conducting fracture zone detection method based on directional drilling detection technology provided in an embodiment of the present invention;

[0037] Figure 4 A schematic diagram of a multi-coal seam directional horizontal drilling area for a water-conducting fracture zone detection method based on directional drilling detection technology provided in an embodiment of the present invention. DETAILED DESCRIPTION

[0038] In order to further explain the technical means and effects adopted by the present invention to achieve the predetermined invention purpose, the following is a detailed description of the specific implementation method, structure, features and effects of a water-conducting fracture zone detection method based on directional drilling detection technology proposed by the present invention in combination with the accompanying drawings and preferred embodiments. In the following description, different "one embodiment" or "another embodiment" does not necessarily refer to the same embodiment. In addition, specific features, structures, or characteristics in one or more embodiments may be combined in any suitable form.

[0039] Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs.

[0040] A specific scheme of a water-conducting fracture zone detection method based on directional drilling detection technology provided by the present invention is described in detail below with reference to the accompanying drawings.

[0041] Example:

[0042] The main application scenarios of the present invention are: Coal mine geological water control is a crucial link in coal mine production safety. Since the integrity of the original rock formation will be destroyed during coal mining, water-conducting fracture zones will be formed. These fracture zones may become channels for groundwater or surface water to enter the mine, thereby causing water disasters. The use of directional drilling detection technology can maximize the advantages of directional drilling and improve the accuracy and spatial form of detection.

[0043] See also Figure 1 , which shows a flow chart of a water-conducting fracture zone detection method based on directional drilling detection technology provided by an embodiment of the present invention, the method comprising the following steps:

[0044] Step S1, determine the single coal seam water-conducting fracture zone exploration area, the multi-coal seam water-conducting fracture zone exploration area and the single coal seam directional horizontal drilling area and the multi-coal seam directional horizontal drilling area, and select the surface drilling position; the surface drilling position includes a first surface drilling position and a second surface drilling position.

[0045] After coal seam mining, its overburden will deform, move and be damaged. A large number of observations show that when longwall mining and full caving methods are used to manage the goaf, the goaf can be divided into "three zones" according to the degree of movement and damage of the overburden, namely the caving zone, the water-conducting fracture zone and the curved sinking zone.

[0046] The collapse zone is the part of the rock layer where the broken rock blocks are separated from the original rock mass and collapse into the goaf in the form of irregular rock blocks or layered blocks. The collapse zone is located at the bottom of the overburden, close to the coal seam. After the coal seam is mined, the overburden loses balance and begins to collapse from the direct top rock layer, and gradually develops upward until the mining space is filled with collapsed rock blocks. There are many gaps between the rock blocks in the collapse zone, and the connectivity is strong, which can become a channel for water and sediment to break into the mine.

[0047] The water-conducting fracture zone is located above the collapse zone. The horizontal deformation, bending and shear deformation of the rock mass produce cracks and breaks. After the rock strata are broken, the rock blocks are still arranged neatly and the continuity of the rock strata is not destroyed. There are two main types of cracks in the fracture zone: one is the newly formed tension cracks that are vertical or oblique to the rock strata, which can partially or completely penetrate the rock strata, but the rock masses on both sides maintain layered continuity; the other is the delamination cracks along the layer surface, which are mainly caused by the large difference in mechanical properties between rock strata and the asynchronous bending and movement of rock strata downward. Because the cracks have strong water conductivity and can seep downward to the goaf, the collapse zone and the water-conducting fracture zone are collectively called "two zones". If the water-conducting fracture zone affects the water body, it can guide water into the well, and generally does not penetrate mud and sand.

[0048] The curved subsidence zone refers to the part of the rock layer from the top of the fracture zone to the surface. Due to the small deformation of the rock mass, although cracks are also generated in the rock mass, water cannot seep into the goaf. The curved subsidence zone moves as a whole and acts as a water-proof protective layer. Delamination cracks can occur in the curved zone and can be locally filled with water. Delamination generally has little effect on the amount of water inflow in the mine.

[0049] The development law of the "two zones" (especially the water-conducting fracture zone) is an important basis for the design of coal mining and water prevention and control. The development law of the "two zones" (especially the water-conducting fracture zone) is an important basis for the design of coal mining and water prevention and control. Article 87 of the "Detailed Rules for Coal Mine Water Prevention and Control" stipulates: When mining under water, the water-proof coal (rock) pillars should be designed and reserved according to the principle of combining the crack angle with the water-proof coal (rock) pillars required by the mining level of the water body. The height of the collapse zone, water-conducting fracture zone, and the thickness of the protective layer of the coal seam (group) can be calculated according to the formula in the "Specifications for the Retention and Compression of Coal Pillars in Buildings, Water Bodies, Railways and Main Wells and Lanes", or determined comprehensively based on the empirical data under actual measurements and similar geological conditions combined with mechanical analysis, numerical simulation, physical simulation and other methods. The height of the collapse zone and water-conducting fracture zone in top coal caving mining or large mining height (more than 3m) comprehensive mining should be comprehensively determined based on various methods such as actual measured data of similar geological conditions in the mining area. When there are medium or higher water-rich aquifers or other water body threats in the coal seam roof, the height of the collapse zone and water-conducting fracture zone should be measured, and special design should be carried out to determine the size of the water-proof coal (rock) pillar.

[0050] According to the "three lower regulations and specifications", the estimated height of the single coal seam water-conducting fracture zone and the estimated height of the multi-coal seam water-conducting fracture zone of the working face to be tested are determined, and then the target layer to be detected is determined according to the estimated height, that is, the exploration area of ​​the single coal seam water-conducting fracture zone and the exploration area of ​​the multi-coal seam water-conducting fracture zone. It should be noted that when determining the target layer, it is necessary to determine it according to the actual situation of the coal mine. For example, when the estimated height of the water-conducting fracture zone of some coal mines is difficult to estimate, the estimated height of the water-conducting fracture zone can be analyzed according to the collapse zone, and the target layer can be determined, or the estimated height of the water-conducting fracture zone can be determined using the corresponding method.

[0051] Furthermore, according to the determined single coal seam water-conducting fracture zone exploration area and multi-coal seam water-conducting fracture zone exploration area, the horizontal layer is determined in combination with the drilling data of the working face to be tested, the mining situation of the working face to be tested, the geological structure and the directional drilling water-vertical ratio. The horizontal layer is also the single coal seam directional horizontal drilling area and the multi-coal seam directional horizontal drilling area; there are two single coal seam directional horizontal drilling areas, and the depths of the two single coal seam directional horizontal drilling areas are different. The shallower one is recorded as the first single coal seam directional horizontal drilling area, and the deeper one is recorded as the second single coal seam directional horizontal drilling area; there are also two multi-coal seam directional horizontal drilling areas, and the depths of the two single coal seam directional horizontal drilling areas are different. The shallower one is recorded as the first multi-coal seam directional horizontal drilling area, and the deeper one is recorded as the second multi-coal seam directional horizontal drilling area.

[0052] Next, the surface drilling location needs to be determined, such as Figure 2 As shown, a set distance is set inside the return air chute and the set distance is set inside the downwind chute on the ground of the working face to be tested, and a straight line LL is made parallel to the chute. A point O1 is found on the straight line. A point O2 is south of O1 on the LL line and the distance from O1 is the set distance. O1 and O2 are the surface drilling positions, which are recorded as the first surface drilling position and the second surface drilling position, respectively. It should be noted that the set distance needs to be set by the implementer according to the actual situation. Preferably, the set distance in the embodiment of the present invention is 20m.

[0053] After coal seam mining, the overburden shows obvious settlement and damage, and cracks develop. A single borehole can only show the development of cracks on a plane, but cannot reflect the spatial situation of the cracks (water-conducting fracture zones). Exploring the target layer (target point) from different drilling positions can solve the problem of incomplete detection of the spatial development of cracks. Therefore, the present invention selects two drilling positions, that is, drilling from the first surface drilling position and the second surface drilling position for detection.

[0054] At the same time, it is also necessary to estimate the drilling speed. The working face to be tested is calculated based on a recovery speed of 180 m / month. The maximum development height of the water-conducting fracture zone is 1 to 2 months after mining. Preferably, the present invention takes 1.5 months. The location of the "two zones" detection height is taken in a specific month. Taking June as an example, the estimated recovery position in June is selected. This position is approximately 2170 m ( Figure 2 The surface drilling will be completed to this location in early to mid-August. The drilling speed can be estimated based on this.

[0055] Step S2, drilling from the first surface drilling position and the second surface drilling position respectively, reaching the multi-coal seam directional horizontal drilling area corresponding to the first surface drilling position and the second surface drilling position respectively, setting a branch inclination point in the multi-coal seam directional horizontal drilling area, drilling from the branch inclination point to reach the multi-coal seam water-conducting fracture zone exploration area for exploration.

[0056] like Figure 3 As shown, vertical construction is carried out at O1 and O2 to obtain the directional main hole (vertical hole) Z d-1 , Z d-2 , Z d-1 , Z d-2 Recorded as the first main hole and the second main hole, then directional inclination is carried out in the corresponding multi-coal seam directional horizontal drilling area, horizontal directional construction is carried out, and directional downward and inclination construction are carried out when the construction reaches the corresponding position. The vertical projections of the multi-coal seam detection terminal hole positions of the three branch holes are located at a set distance inside the inner wall of the return air chute of the mining working face above the working face to be tested, a set distance inside the inner wall of the transport chute, and the center of the working face, respectively, recorded as D, F and E.

[0057] like Figure 4 As shown, specifically, vertical drilling is performed from the first main hole and the second main hole to the inclination point I respectively, and the multi-coal seam directional horizontal drilling areas corresponding to the first surface drilling position and the second surface drilling position are reached, wherein the first surface drilling position corresponds to the shallower one of the two multi-coal seam directional horizontal drilling areas, and the second surface drilling position corresponds to the deeper one of the two multi-coal seam directional horizontal drilling areas, which are the first multi-coal seam directional horizontal drilling area and the second multi-coal seam directional horizontal drilling area, respectively. Figure 4 The inclination point I in the figure represents two inclination points located in the first multi-coal seam directional horizontal drilling area and the second multi-coal seam directional horizontal drilling area respectively.

[0058] Then, three branch inclination points are set in the first multi-coal seam directional horizontal drilling area and the second multi-coal seam directional horizontal drilling area. Figure 4In the figure, it is represented as branch inclination point I-1, branch inclination point I-2 and branch inclination point I-3; taking the first multi-coal seam directional horizontal drilling area as an example, horizontal directional drilling is carried out at inclination point I, drilling to branch inclination point I-1, inclination is built downward, and the multi-coal seam water-conducting fracture zone exploration area is reached, and the development height of the water-conducting fracture zone at a set distance inside the inner wall of the return air chute D of the mined working face above the working face to be tested is detected, and plugging and backfilling are carried out after the detection is completed; horizontal drilling is continued to reach the branch inclination point Point I-2, build inclination downward to reach the exploration area of ​​multi-coal seam water-conducting fracture zone, detect the development height of the water-conducting fracture zone at the center of the mined working face E above the working face to be tested, and plug and backfill after the detection is completed; continue to drill horizontally to reach the branch inclination point I-3, build inclination downward to reach the exploration area of ​​multi-coal seam water-conducting fracture zone, detect the development height of the water-conducting fracture zone at a set distance inside the inner wall of the mined working face transportation chute (F) above the working face to be tested, and plug and backfill after the detection is completed. Use points D, E, and F to detect the development height and spatial state of the multi-coal seam mining water-conducting fracture zone.

[0059] Drilling is performed from the first surface drilling position and the second surface drilling position respectively. During the drilling process, only the multi-coal seam directional horizontal drilling area reached and the inclination point I are different, and the position of the multi-coal seam water-conducting fracture zone exploration area finally reached is the same.

[0060] It should be noted that drilling is performed from the first surface drilling position and the second surface drilling position respectively to reach the inclination point in the first multi-coal seam directional horizontal drilling area and the inclination point in the second multi-coal seam directional horizontal drilling area corresponding to the first surface drilling position and the second surface drilling position respectively; horizontal drilling is performed from the inclination point in the first multi-coal seam directional horizontal drilling area to reach the three set branch inclination points respectively, and inclination is performed downward to reach the multi-coal seam detection end hole position in the multi-coal seam water-conducting fracture zone exploration area respectively, to detect the mining working face above the working face to be tested. The height of the water-conducting fracture zone at a set distance inside the inner wall of the return air chute, at a set distance inside the inner wall of the transport chute, and at the center of the working face; horizontal drilling is carried out from the inclination point in the second multi-coal seam directional horizontal drilling area to reach the three set branch inclination points, and inclination is built downward to reach the multi-coal seam detection terminal hole position in the multi-coal seam water-conducting fracture zone exploration area, and the height of the water-conducting fracture zone at a set distance inside the inner wall of the return air chute, at a set distance inside the inner wall of the transport chute, and at the center of the working face of the mining face above the working face to be tested is detected.

[0061] Step S3, drilling from the multi-coal seam directional horizontal drilling areas corresponding to the first surface drilling position and the second surface drilling position respectively, reaching the single coal seam directional horizontal drilling area corresponding to the first surface drilling position and the second surface drilling position respectively, setting a branch inclination point in the single coal seam directional horizontal drilling area, drilling from the branch inclination point to reach the single coal seam water-conducting fracture zone exploration area for exploration.

[0062] After completing the exploration of the multi-coal seam water-conducting fracture zone exploration area, the first main hole Z d-1 and the second main hole Z d-2 Continue drilling, that is, continue drilling from the inclination point I, and then explore the single coal seam water-conducting fracture zone exploration area.

[0063] Specifically, drilling is carried out from the inclination point I in the first multi-coal seam directional horizontal drilling area and the second multi-coal seam directional horizontal drilling area respectively to reach the inclination point II in the single coal seam directional horizontal drilling area corresponding to the first surface drilling position and the second surface drilling position respectively, wherein the first surface drilling position corresponds to the shallower one of the two single coal seam directional horizontal drilling areas, and the second surface drilling position corresponds to the deeper one of the two single coal seam directional horizontal drilling areas, which are the first single coal seam directional horizontal drilling area and the second single coal seam directional horizontal drilling area respectively.

[0064] Drill horizontally from the inclining point in the first single coal seam directional horizontal drilling area to the three branch inclining points set in the first single coal seam directional horizontal drilling area, and incline downward to the single coal seam detection end hole position in the single coal seam water-conducting fracture zone exploration area, and detect the development height of the water-conducting fracture zone at a set distance inside the inner wall of the return air chute of the working face to be tested, a set distance inside the inner wall of the transport chute, and the center of the working face; drill horizontally from the inclining point in the second single coal seam directional horizontal drilling area to the three branch inclining points set in the second single coal seam directional horizontal drilling area, and incline downward to the single coal seam detection end hole position in the single coal seam water-conducting fracture zone exploration area, and detect the development height of the water-conducting fracture zone at a set distance inside the inner wall of the return air chute of the working face to be tested, a set distance inside the inner wall of the transport chute, and the center of the working face.

[0065] Take the drilling of the first surface drilling position as an example. Figure 4 As shown, the drilling is carried out into the first single coal seam directional horizontal drilling area, and three branch inclination points are set in the first single coal seam directional horizontal drilling area. Figure 4In the figure, it is represented by branch inclining point II-1, branch inclining point II-2 and branch inclining point II-3, and then horizontal directional drilling is carried out at inclining point II. Drilling to branch inclining point II-1, inclining downward, reaching the exploration area of ​​single coal seam water-conducting fracture zone, detecting the development height of water-conducting fracture zone at a set distance inside the inner wall of return air chute A of the working face to be tested, and plugging and backfilling are carried out after the detection is completed; continuing horizontal drilling to branch inclining point II-2, inclining downward, reaching the exploration area of ​​single coal seam water-conducting fracture zone, detecting the development height of water-conducting fracture zone at B in the center of the working face to be tested, and plugging and backfilling are carried out after the detection is completed; continuing horizontal drilling to branch inclining point II-3, inclining downward, reaching the exploration area of ​​single coal seam water-conducting fracture zone, detecting the development height of water-conducting fracture zone at a set distance inside the inner wall of transport chute C of the working face to be tested, and plugging and backfilling are carried out after the detection is completed. The three points A, B and C are used to detect the development height and spatial state of the water-conducting fracture zone caused by mining in a single coal seam.

[0066] The drilling exploration of the development height and spatial state of the single coal seam mining water-conducting fracture zone from the second surface drill hole position is similar to the drilling exploration of the development height and spatial state of the single coal seam mining water-conducting fracture zone from the first surface drill hole position. The difference lies in the different single coal seam directional horizontal drilling areas reached. The single coal seam directional horizontal drilling area reached is the second single coal seam directional horizontal drilling area, and the final positions of its three branch holes are consistent with the final positions of the corresponding three branch holes drilled from the first surface drill hole position, and are within the single coal seam water-conducting fracture zone exploration area.

[0067] Step S4, obtaining the fracture zone development conditions of the single coal seam water-conducting fracture zone exploration area and the multi-coal seam water-conducting fracture zone exploration area.

[0068] Based on the slurry loss during drilling, gamma logging while drilling, cuttings logging combined with mine drilling data, hydrogeological conditions and structural conditions, a comprehensive analysis is conducted to determine the development height and spatial morphology of water-conducting fracture zones in single and multi-coal seam mining.

[0069] Among them, the methods for judging the height of water-conducting fracture zones include:

[0070] 1) The development height of the water-conducting fracture zone is judged according to the slurry leakage during the drilling process. If the leakage volume increases significantly, it means that the development height of the water-conducting fracture zone has been reached.

[0071] 2) Based on the rock debris carried by the drilling slurry during drilling during the cuttings logging process, the area where the water-conducting fracture zone is developed can be judged. If the rock debris is obviously black, it means that the drilling has entered the cross-fall zone, thereby judging the development height of the water-conducting fracture zone.

[0072] 3) Based on logging data, microresistivity scanning, spontaneous gamma, sonic, neutron logging and other methods, determine the development height of the water-conducting fracture zone and the porosity of the overlying rock.

[0073] 4) Use infrared endoscope to observe the development of cracks inside the borehole.

[0074] In the present invention, in the process of drilling from the branch deflection point of the first multi-coal seam directional horizontal drilling area to the multi-coal seam water-conducting fracture zone exploration area, the longitudinal fracture development of the multi-coal seam water-conducting fracture zone is determined according to the drilling slurry loss, the borehole peep instrument and the while-drilling gamma logging;

[0075] In the process of drilling from the branch deflection point of the second multi-coal seam directional horizontal drilling area to the multi-coal seam water-conducting fracture zone exploration area, the development of lateral fractures in the multi-coal seam water-conducting fracture zone is determined based on the drilling slurry loss, borehole peep instrument and while-drilling gamma logging;

[0076] In the process of drilling from the branch deflection point in the first single coal seam directional horizontal drilling area to the exploration area of ​​the single coal seam water-conducting fracture zone, the development of the longitudinal fractures in the single coal seam water-conducting fracture zone is determined based on the drilling slurry loss, the borehole peep instrument and the while-drilling gamma logging;

[0077] In the process of drilling from the branch deflection point in the second single coal seam directional horizontal drilling area to the exploration area of ​​the single coal seam water-conducting fracture zone, the development of lateral fractures in the single coal seam water-conducting fracture zone is determined based on the drilling slurry loss, borehole peep instrument and while-drilling gamma logging;

[0078] According to the development of longitudinal fractures in the multi-coal seam water-conducting fracture zones and the development of transverse fractures in the multi-coal seam water-conducting fracture zones, a full-time and space schematic diagram of the multi-coal seam water-conducting fracture zones is drawn to obtain the development of fracture zones in the exploration area of ​​the multi-coal seam water-conducting fracture zones;

[0079] According to the development of longitudinal fractures in the single coal seam water-conducting fracture zone and the development of transverse fractures in the single coal seam water-conducting fracture zone, a full-time and space schematic diagram of the single coal seam water-conducting fracture zone is drawn, and the development of the fracture zone in the exploration area of ​​the single coal seam water-conducting fracture zone is obtained.

[0080] It should be noted that the sequence of the above embodiments of the present invention is only for description and does not represent the advantages and disadvantages of the embodiments. The above is a description of a specific embodiment of this specification. In addition, the processes depicted in the accompanying drawings do not necessarily require the specific order or continuous order shown to achieve the desired results. In some embodiments, multitasking and parallel processing are also possible or may be advantageous.

[0081] The various embodiments in this specification are described in a progressive manner, and the same or similar parts between the various embodiments can be referenced to each other, and each embodiment focuses on the differences from other embodiments.

[0082] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. A method for detecting water-conducting fracture zones based on directional drilling detection technology, characterized in that: The method includes: Determine a single coal seam water-conducting fracture zone exploration area, a multi-coal seam water-conducting fracture zone exploration area, a single coal seam directional horizontal drilling area, and a multi-coal seam directional horizontal drilling area, and select surface drilling positions; the surface drilling positions include a first surface drilling position and a second surface drilling position; Drilling is performed from a first surface drilling position and a second surface drilling position respectively to reach the multi-coal seam directional horizontal drilling area corresponding to the first surface drilling position and the second surface drilling position respectively, a branching deflection point is set in the multi-coal seam directional horizontal drilling area, and drilling is performed from the branching deflection point to reach the multi-coal seam water-conducting fracture zone exploration area for exploration; Drilling from the multi-coal seam directional horizontal drilling areas corresponding to the first surface drilling position and the second surface drilling position respectively, reaching the single coal seam directional horizontal drilling areas corresponding to the first surface drilling position and the second surface drilling position respectively, setting a branch deflection point in the single coal seam directional horizontal drilling area, drilling from the branch deflection point to reach the single coal seam water-conducting fracture zone exploration area for exploration; Obtain the fracture zone development conditions of single coal seam water-conducting fracture zone exploration areas and multi-coal seam water-conducting fracture zone exploration areas; The surface drilling position includes: Draw a straight line parallel to the return air chute at a set distance and the downwind chute at a set distance on the working face to be tested, find a point on the straight line as the first surface drilling position, and find a point on the straight line to the south of the first surface drilling position and at a set distance from the first surface drilling position as the second surface drilling position; The method of drilling holes from a first surface drilling position and a second surface drilling position respectively to reach a multi-coal seam directional horizontal drilling area includes: Vertically construct at the first surface drilling position and the second surface drilling position respectively to obtain directional main holes, which are recorded as the first main hole and the second main hole; reach the inclination point located in the first multi-coal seam directional horizontal drilling area from the first main hole, and reach the inclination point located in the second multi-coal seam directional horizontal drilling area from the second main hole; The method of setting a branch deflection point in a multi-coal seam directional horizontal drilling area, drilling from the branch deflection point to reach a multi-coal seam water-conducting fracture zone exploration area for exploration, comprises: Drill horizontally from the inclination point in the first multi-coal seam directional horizontal drilling area to the three branch inclination points set in the first multi-coal seam directional horizontal drilling area, incline downwards, respectively reach the multi-coal seam detection end hole positions in the multi-coal seam water-conducting fracture zone exploration area, and detect the development height of the water-conducting fracture zone at a set distance inside the inner wall of the return air chute of the mining working face above the working face to be tested, at a set distance inside the inner wall of the transport chute, and at the center of the working face; drill horizontally from the inclination point in the second multi-coal seam directional horizontal drilling area to the three branch inclination points set in the second multi-coal seam directional horizontal drilling area, incline downwards, respectively reach the multi-coal seam detection end hole positions in the multi-coal seam water-conducting fracture zone exploration area, and detect the development height of the water-conducting fracture zone at a set distance inside the inner wall of the return air chute of the mining working face above the working face to be tested, at a set distance inside the inner wall of the transport chute, and at the center of the working face; The single coal seam directional horizontal drilling area corresponding to the first surface drilling position and the second surface drilling position respectively includes: Drill downward from the inclination points in the first multi-coal seam directional horizontal drilling area and the second multi-coal seam directional horizontal drilling area respectively to reach the inclination point in the first single coal seam directional horizontal drilling area and the inclination point in the second single coal seam directional horizontal drilling area.

2. The method for detecting water-conducting fracture zones based on directional drilling detection technology according to claim 1, characterized in that: Determining the single coal seam water-conducting fracture zone exploration area and the multi-coal seam water-conducting fracture zone exploration area includes: Obtain the estimated height of the single coal seam water-conducting fracture zone and the estimated height of the multi-coal seam water-conducting fracture zone of the working face to be tested; determine the single coal seam water-conducting fracture zone exploration area and the multi-coal seam water-conducting fracture zone exploration area respectively according to the estimated height of the single coal seam water-conducting fracture zone and the estimated height of the multi-coal seam water-conducting fracture zone.

3. The method for detecting water-conducting fracture zones based on directional drilling detection technology according to claim 1, characterized in that: The single coal seam directional horizontal drilling area and the multi-coal seam directional horizontal drilling area include: According to the single coal seam water-conducting fracture zone exploration area and the multi-coal seam water-conducting fracture zone exploration area, combined with the drilling data of the working face to be tested, the mining situation of the working face to be tested, the geological structure and the directional drilling water-vertical ratio, the single coal seam directional horizontal drilling area and the multi-coal seam directional horizontal drilling area are determined; there are two single coal seam directional horizontal drilling areas, and the two single coal seam directional horizontal drilling areas have different depths. The shallower one is recorded as the first single coal seam directional horizontal drilling area, and the deeper one is recorded as the second single coal seam directional horizontal drilling area; there are also two multi-coal seam directional horizontal drilling areas, and the two multi-coal seam directional horizontal drilling areas have different depths. The shallower one is recorded as the first multi-coal seam directional horizontal drilling area, and the deeper one is recorded as the second multi-coal seam directional horizontal drilling area.

4. The method for detecting water-conducting fracture zones based on directional drilling detection technology according to claim 1, characterized in that: The method of setting a branch deflection point in the single coal seam directional horizontal drilling area, drilling from the branch deflection point to reach the single coal seam water-conducting fracture zone exploration area for exploration, includes: Drill horizontally from the inclining point in the first single coal seam directional horizontal drilling area to the three branch inclining points set in the first single coal seam directional horizontal drilling area, and incline downward to the single coal seam detection end hole position in the single coal seam water-conducting fracture zone exploration area, and detect the development height of the water-conducting fracture zone at a set distance inside the inner wall of the return air chute of the working face to be tested, a set distance inside the inner wall of the transport chute, and the center of the working face; drill horizontally from the inclining point in the second single coal seam directional horizontal drilling area to the three branch inclining points set in the second single coal seam directional horizontal drilling area, and incline downward to the single coal seam detection end hole position in the single coal seam water-conducting fracture zone exploration area, and detect the development height of the water-conducting fracture zone at a set distance inside the inner wall of the return air chute of the working face to be tested, a set distance inside the inner wall of the transport chute, and the center of the working face.

5. The method for detecting water-conducting fracture zones based on directional drilling detection technology according to claim 1, characterized in that: The method of obtaining the fracture zone development conditions of the single coal seam water-conducting fracture zone exploration area and the multi-coal seam water-conducting fracture zone exploration area includes: In the process of drilling from the branch deflection point of the first multi-coal seam directional horizontal drilling area to the multi-coal seam water-conducting fracture zone exploration area, the development of longitudinal fractures in the multi-coal seam water-conducting fracture zone is determined based on the drilling slurry loss, borehole peep instrument and while-drilling gamma logging; In the process of drilling from the branch deflection point of the second multi-coal seam directional horizontal drilling area to the multi-coal seam water-conducting fracture zone exploration area, the development of lateral fractures in the multi-coal seam water-conducting fracture zone is determined based on the drilling slurry loss, borehole peep instrument and while-drilling gamma logging; In the process of drilling from the branch deflection point in the first single coal seam directional horizontal drilling area to the exploration area of ​​the single coal seam water-conducting fracture zone, the development of the longitudinal fractures in the single coal seam water-conducting fracture zone is determined based on the drilling slurry loss, the borehole peep instrument and the while-drilling gamma logging; In the process of drilling from the branch deflection point in the second single coal seam directional horizontal drilling area to the exploration area of ​​the single coal seam water-conducting fracture zone, the development of lateral fractures in the single coal seam water-conducting fracture zone is determined based on the drilling slurry loss, borehole peep instrument and while-drilling gamma logging; According to the development of longitudinal fractures in the multi-coal seam water-conducting fracture zones and the development of transverse fractures in the multi-coal seam water-conducting fracture zones, a full-time and space schematic diagram of the multi-coal seam water-conducting fracture zones is drawn to obtain the development of fracture zones in the exploration area of ​​the multi-coal seam water-conducting fracture zones; According to the development of longitudinal fractures in the single coal seam water-conducting fracture zone and the development of transverse fractures in the single coal seam water-conducting fracture zone, a full-time and space schematic diagram of the single coal seam water-conducting fracture zone is drawn, and the development of the fracture zone in the exploration area of ​​the single coal seam water-conducting fracture zone is obtained.

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