A dry hot rock exploitation method based on integration of impact drilling and auxiliary fracturing

Abstract

The application discloses a dry hot rock exploitation method based on integration of percussive drilling and auxiliary fracturing, and comprises the following steps: S1, preparing a drill bit, the drill bit can break bottom hole rock and damage a well wall; S2, adopting a multi-target optimization method to determine structure parameters of the drill bit and percussive drilling parameters; S3, selecting the drill bit according to the structure parameters determined in the step S2, combining the percussive drilling parameters, adopting a percussive drilling method to drill a target well, and carrying out fracturing construction on the basis of well wall damage. The application adopts the multi-target optimization method, constructs a multi-target optimization function, selects appropriate drill bit structure and percussive parameters, maximizes the advantages of the percussive drilling technology in dry hot rock drilling and exploitation, breaks stratum rock efficiently while inducing micro cracks in the rock around the well, can guarantee well wall stability, effectively reduce fracturing construction pressure and increase the complexity of cracks, and realizes multiple targets of safe and efficient drilling of the dry hot rock and auxiliary reservoir reconstruction.

Description

Technical Field

[0001] This invention relates to the field of hot dry rock development technology, and in particular to a hot dry rock mining method based on the integration of percussion drilling and assisted fracturing. Background Technology

[0002] With the rapid development of my country's economy and society, resource consumption has also increased dramatically. In 2022, the dependence on foreign oil and natural gas reached 71.2% and 40.2% respectively, highlighting a significant supply-demand imbalance. On the other hand, environmental problems caused by the combustion of fossil fuels are becoming increasingly apparent. Against this backdrop, vigorously developing clean energy sources such as geothermal, wind, solar, and hydrogen energy has become an important path to sustainable development. Compared with other clean energy sources, hot dry rock has advantages such as good stability, immunity to environmental impact, and vast resource reserves. Statistics show that my country's hot dry rock resources within the 3-10km range are approximately 2.52 × 10⁻⁶ km². 25 J, equivalent to 860 trillion tons of standard coal, is the most promising strategic alternative energy source.

[0003] However, developing hot dry rock is extremely challenging. Firstly, hot dry rock reservoirs are characterized by four "highs": high temperature, high strength, high hardness, and high abrasiveness. This leads to a series of problems, including easy drill bit wear, short drilling footage, and low drilling speed. Currently, drilling costs remain high, accounting for 50%-70% of the total cost of hot dry rock development. Secondly, enhanced geothermal systems (EGS) have become a common method for hot dry rock development. This involves creating a fracture network between two adjacent wells through fracturing, followed by efficient extraction of reservoir heat using a single injection and production process. However, the high strength and high in-situ stress of hot dry rock reservoirs significantly increase the difficulty of reservoir stimulation. For example, in the Pohang hot dry rock in South Korea, hydraulic fracturing was performed at a depth of 4100 meters, but the reservoir failed to be broken open even after pumping pressures exceeding 100 MPa. EGS projects in this area have also induced a magnitude 5.4 earthquake. Similarly, in Basel, Switzerland, the dry hot rock mass induced more than 15,000 microseismic events during hydraulic fracturing and water injection, with the highest magnitude reaching 3.4, directly leading to the termination of the project.

[0004] Currently, hot dry rock fracturing mainly relies on connecting natural fractures to effectively reduce the initiation pressure. However, this method is prone to problems such as poor reservoir stimulation, limited fracture types, and uncontrollable fracture propagation direction. For example, in the Rosemanowes EGS project in the UK, fracturing occurred at a depth of 2100 meters in a deviated well, but the fracture did not connect to the injection and production wells; instead, it extended deeper into the rock mass to 4500 meters. Therefore, if some microfractures can be artificially created before fracturing operations, it can effectively reduce the initiation pressure, increase the complexity of the fractures, control the direction of fracture propagation, and significantly improve the EGS operation results. Summary of the Invention

[0005] To address the aforementioned problems, this invention aims to provide a method for mining hot dry rock based on the integration of percussion drilling and assisted fracturing.

[0006] The technical solution of the present invention is as follows: A method for mining hot dry rock based on integrated percussion drilling and assisted fracturing includes the following steps: S1: Prepare the drill bit, which can both break the rock at the bottom of the well and damage the well wall to induce microcracks in the well wall; S2: The structural parameters and percussion drilling parameters of the drill bit are determined using a multi-objective optimization method; S3: Select the optimal drill bit based on the structural parameters determined in step S2, and combine it with the percussion drilling parameters to drill the target well using the percussion drilling method, and carry out fracturing operations on the basis of well wall damage.

[0007] Preferably, at least some of the cutting teeth on the outermost ring of the drill bit are inclined in a direction away from the central axis of the drill bit, and the tips of the inclined cutting teeth are located outside the outer diameter of the drill bit body; the cutting teeth on the inner ring of the drill bit are all arranged in a vertical direction.

[0008] Preferably, all the cutting teeth on the outermost ring of the drill bit are inclined in a direction away from the central axis of the drill bit.

[0009] Preferably, the outermost cutting teeth of the drill bit include a conical tooth and a spherical tooth, and the conical tooth and the spherical tooth are staggered, with the exposed height of the spherical tooth being less than that of the conical tooth.

[0010] Preferably, the cutting teeth of the inner ring of the drill bit include two conical teeth and two spherical teeth, and the two conical teeth and two spherical teeth of the same inner ring are staggered, and the exposed height of the two spherical teeth is less than the exposed height of the two conical teeth.

[0011] Preferably, the cutting teeth of the drill bit are all PDC teeth.

[0012] Preferably, step S2 specifically includes the following sub-steps: S21: Based on the target drilling location and its corresponding engineering design, conduct surface drilling tests on outcrops at different strata to obtain surface drilling test data; S22: Based on the aforementioned ground drilling test data, establish the functional relationships between mechanical drilling rate and drill bit structural parameters and impact drilling parameters (I) and rock breaking efficiency and drill bit structural parameters and impact drilling parameters (II) through data regression analysis. S23: Take a core sample from the wellbore location after drilling the rock sample in step S21, measure its rock strength, and compare it with the original rock strength to obtain the rock strength ratio; the original rock strength is the rock strength at a location far from the wellbore. S24: Establish the functional relationship between the rock strength ratio and the drill bit structural parameters and impact drilling parameters; S25: Uncored rock samples are run into the fracturing string along the wellbore to conduct a surface fracturing test, and the formation initiation pressure is recorded. After the test, the rock samples are cut along the center of the wellbore, and the fractal dimension is used to describe the complexity of the fracture. S26: Establishing the functional relationship between fracture initiation pressure and drill bit structural parameters and percussion drilling parameters; IV. Functional relationship between fracture complexity and drill bit structural parameters and percussion drilling parameters; V. S27: Construct a multi-objective optimization function for mechanical drilling rate, rock breaking efficiency, rock strength ratio, fracture initiation pressure and fracture complexity based on the functional relationships one to five; S28: Solve the multi-objective optimization function according to the actual situation of the target well to determine the drill bit structure parameters and impact drilling parameters.

[0013] Preferably, in step S22, the rock-breaking efficiency is evaluated by mechanical specific energy.

[0014] Preferably, in step S27, the multi-objective optimization function is: Max f(x,y)=[a ROP(x,y),-b MSE(x,y),c USEratio(x,y),-d P(x,y),e FRA(x,y)] (1) In the formula: x represents the drill bit structural parameters; y represents the percussion drilling parameters; a, b, c, d, and e are all weighting coefficients; ROP(x,y) is the first functional relationship between mechanical drilling rate and drill bit structural parameters and percussion drilling parameters; MSE(x,y) is the second functional relationship between rock breaking efficiency and drill bit structural parameters and percussion drilling parameters; USEratio(x,y) is the third functional relationship between rock strength ratio and drill bit structural parameters and percussion drilling parameters; P(x,y) is the fourth functional relationship between fracture initiation pressure and drill bit structural parameters and percussion drilling parameters; FRA(x,y) is the fifth functional relationship between fracture complexity and drill bit structural parameters and percussion drilling parameters.

[0015] Preferably, when drilling in non-reservoir sections, the weighting coefficients for fracture initiation pressure and fracture complexity are set to 0.

[0016] The beneficial effects of this invention are: This invention employs a multi-objective optimization method to construct a multi-objective optimization function, selects appropriate drill bit structures and impact parameters, and maximizes the advantages of percussion drilling technology in hot dry rock drilling and production. While efficiently fracturing formation rocks, it induces an appropriate amount of microcracks in the rocks around the well, which can ensure wellbore stability, effectively reduce fracturing construction pressure, and increase the complexity of fractures, thus achieving multiple objectives of safe and efficient drilling in hot dry rocks and auxiliary reservoir stimulation. Attached Figure Description

[0017] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0018] Figure 1 Schematic diagram of core sampling from the wellbore in an impact drilling experiment; Figure 2 A schematic diagram illustrating efficient drilling into hot dry rock using percussion drilling techniques; Figure 3 This is a schematic diagram of the drill bit structure in a specific embodiment; Figure 4 This is a schematic diagram of reservoir fracturing after impact drilling, as shown in a specific embodiment.

[0019] The numbers in the diagram are: 1-Drill pipe, 2-Formation, 3-Impactor, 4-Drill bit, 5-Conical PDC tooth, 6-Stone cuttings, 7-Microcrack, 8-Spherical PDC tooth, 9-Inclination angle, 10-Same circumference of drill bit, 11-Outer diameter of drill bit body, 12-Fracturing string, 13-Packer, 14-Fracturing pump set, 15-Fracturing fluid, 16-Volume fracture network, 17-Core. Detailed Implementation

[0020] The present invention will be further described below with reference to the accompanying drawings and embodiments. It should be noted that, unless otherwise specified, the embodiments and technical features described in this application can be combined with each other. It should also be pointed out that, unless otherwise indicated, all technical and scientific terms used in this application have the same meaning as commonly understood by one of ordinary skill in the art to which this application pertains. The terms "comprising" or "including" and similar words used in this invention refer to elements or objects preceding the word that encompass the elements or objects listed following the word and their equivalents, without excluding other elements or objects.

[0021] This invention provides a method for mining hot dry rock based on integrated percussion drilling and assisted fracturing, comprising the following steps: S1: Prepare the drill bit, which can both break the rock at the bottom of the well and damage the well wall to induce microcracks in the well wall.

[0022] In one specific embodiment, at least some of the cutting teeth on the outermost ring of the drill bit are inclined away from the central axis of the drill bit, and the tips of the inclined cutting teeth are located outside the outer diameter of the drill bit body; the cutting teeth on the inner ring of the drill bit are all arranged vertically. Optionally, all the cutting teeth on the outermost ring of the drill bit are inclined away from the central axis of the drill bit.

[0023] In the above embodiments, the outermost cutting teeth are set at a certain angle, which allows some energy to be transferred to the bottom of the well for rock breaking under impact load, while the other part of the energy is transferred to the well wall to damage the well wall and induce microcracks, thus achieving efficient rock breaking and well wall damage. The angled cutting tooth tips are positioned outside the outer diameter of the drill bit body, which protects the drill bit body during drilling. The inner cutting teeth are vertically positioned so that all impact energy is applied to the bottom of the well, achieving efficient rock breaking and drill bit advancement.

[0024] In one specific embodiment, the outermost cutting teeth of the drill bit include a conical tooth and a spherical tooth, which are staggered, and the exposed height of the spherical tooth is less than that of the conical tooth. The inner cutting teeth of the drill bit include a second conical tooth and a second spherical tooth, which are staggered within the same inner ring, and the exposed height of the spherical tooth is less than that of the conical tooth. Optionally, the first and second conical teeth have the same structure, and the first and second spherical teeth have the same structure.

[0025] In the above embodiment, the spherical teeth and conical teeth are staggered, and the exposed height of the spherical teeth is less than that of the conical teeth. When the impact load is too large or the formation is severely mixed with soft and hard strata, the spherical teeth can limit the drill bit's penetration depth and absorb part of the impact load, thus protecting the drill bit.

[0026] In one specific embodiment, the cutting teeth of the drill bit are all PDC teeth.

[0027] S2: The structural parameters and percussion drilling parameters of the drill bit are determined using a multi-objective optimization method.

[0028] In a specific embodiment, step S2 specifically includes the following sub-steps: S21: Based on the target drilling location and its corresponding engineering design, conduct surface drilling tests on outcrops at different strata to obtain surface drilling test data; S22: Based on the aforementioned ground drilling test data, establish the functional relationships between mechanical drilling rate and drill bit structural parameters and impact drilling parameters (I) and rock breaking efficiency and drill bit structural parameters and impact drilling parameters (II) through data regression analysis. In one specific embodiment, the rock-breaking efficiency is evaluated by mechanical specific energy, which specifically means the energy consumed to break a unit volume of rock.

[0029] S23: As Figure 1 As shown, core samples were taken from the wellbore location of the rock sample after drilling test in step S21 to obtain rock core 17. The rock strength was measured and compared with the original rock strength to obtain the rock strength ratio; the original rock strength is the rock strength at a location far from the wellbore. S24: Establish the functional relationship between the rock strength ratio and the drill bit structural parameters and impact drilling parameters; S25: Uncored rock samples are run into the fracturing string along the wellbore to conduct a surface fracturing test, and the formation initiation pressure is recorded. After the test, the rock samples are cut along the center of the wellbore, and the fractal dimension is used to describe the complexity of the fracture. S26: Establishing the functional relationship between fracture initiation pressure and drill bit structural parameters and percussion drilling parameters; IV. Functional relationship between fracture complexity and drill bit structural parameters and percussion drilling parameters; V. S27: Construct a multi-objective optimization function for mechanical drilling rate, rock breaking efficiency, rock strength ratio, fracture initiation pressure and fracture complexity based on the functional relationships one to five; In a specific embodiment, the multi-objective optimization function is: Max f(x,y)=[a ROP(x,y),-b MSE(x,y),c USEratio(x,y),-d P(x,y),e FRA(x,y)] (1) In the formula: x represents the drill bit structural parameters; y represents the percussion drilling parameters; a, b, c, d, and e are all weighting coefficients; ROP(x,y) is the first functional relationship between mechanical drilling rate and drill bit structural parameters and percussion drilling parameters; MSE(x,y) is the second functional relationship between rock breaking efficiency and drill bit structural parameters and percussion drilling parameters; USEratio(x,y) is the third functional relationship between rock strength ratio and drill bit structural parameters and percussion drilling parameters; P(x,y) is the fourth functional relationship between fracture initiation pressure and drill bit structural parameters and percussion drilling parameters; FRA(x,y) is the fifth functional relationship between fracture complexity and drill bit structural parameters and percussion drilling parameters.

[0030] In a specific embodiment, when drilling in a non-reservoir section, the weighting coefficients for fracturing initiation pressure and fracture complexity are set to 0. Therefore, the multi-objective optimization function can be simplified as follows: Max f(x,y)=[a ROP(x,y),-b MSE(x,y),c USEratio(x,y)](2) At this point, the values ​​of the other three weighting coefficients, as well as the values ​​of the five weighting coefficients when drilling in the reservoir section, are all set according to objective needs. It should be noted that when setting the weighting coefficients, the drilling cycle can be shortened by increasing the weighting coefficient of ROP, the drilling energy consumption can be reduced by increasing the weighting coefficient of MSE, the USEratio weighting coefficient can be increased in fractured formations to ensure safe drilling, and the P and FRA weighting coefficients can be increased in the reservoir section to fully ensure the efficiency of hot dry rock mining.

[0031] S28: Solve the multi-objective optimization function according to the actual situation of the target well to determine the drill bit structure parameters and impact drilling parameters.

[0032] It should be noted that when solving the multi-objective optimization function, constraints are set in conjunction with the equipment's working capacity, such as the range of drilling pressure, rotation speed, and impact parameters. Then, multi-objective optimization and decision-making are carried out in combination with the specific situation to determine the drill bit structure parameters and impact drilling parameters.

[0033] In the above embodiments, the efficiency of drilling in hot dry rock can be measured by mechanical drilling rate and rock breaking efficiency, the wellbore stability can be measured by core strength ratio, and the reservoir stimulation efficiency can be measured by fracturing pressure and fracture complexity. This allows for the optimization of drill bit structural parameters (tooth height difference of different types, tooth density, tooth inclination angle, etc.) and percussion drilling parameters (impact load amplitude, load shape, and impact frequency, etc.), while ensuring wellbore stability and efficient rock breaking, reducing reservoir stimulation pressure, and enhancing the stimulation effect.

[0034] S3: Select the optimal drill bit based on the structural parameters determined in step S2, and combine it with the percussion drilling parameters to drill the target well using the percussion drilling method, and carry out fracturing operations on the basis of well wall damage.

[0035] In one specific embodiment of fracturing operations using this invention, a low-density foam drilling fluid is used. Since hot dry rock reservoirs are essentially fluid-free, there is no need to consider balancing formation pressure during drilling. Using a low-density foam drilling fluid reduces drilling fluid loss and maintains wellbore stability. The circulating foam drilling fluid also cools the drill bit and promptly carries drilling cuttings to the surface. After drilling is complete and a full wellbore is formed, a fracturing string is run into the high-temperature reservoir section to begin fracturing operations. At this point, under the influence of microcracks induced by drilling impact loads, the fracturing pressure is significantly reduced, and multiple microcracks can simultaneously initiate and propagate along the wellbore, forming a complex fracture network that significantly improves formation heat extraction.

[0036] Taking a certain hot dry rock as an example, the hot dry rock mining method based on the integration of percussion drilling and assisted fracturing described in this invention is used for mining. In the hot dry rock drilling process of this embodiment, as follows: Figure 2-4As shown, drilling is carried out using drill pipe 1 connected to impactor 3 and drill bit 4. Impactor 3, depending on its structure, can generate axial or torsional impact loads. After acting on drill bit 4, the conical PDC teeth 5 and spherical PDC teeth 8 installed on the drill bit effectively break the rock. The resulting rock cuttings 6 are returned to the surface along the annulus between drill pipe 1 and formation 2 under the circulation of foam drilling fluid. The PDC teeth on the outside of drill bit 4, near the well wall, are designed with a certain inclination angle 9. Under this angle, a certain proportion of the impact energy can act on the well wall, thereby inducing microcracks 7 at the well wall location, while the other part of the energy is used to break the rock. Simultaneously, under the influence of the inclination angle 9, the tips of the conical teeth are located outside the outer diameter 11 of the drill bit body, serving to protect the drill bit body. The inclination angle of all PDC teeth inside the drill bit is set to 0, i.e., the teeth are arranged vertically, ensuring that all impact energy acts on the bottom of the well, achieving efficient rock breaking and drilling. Among them, the exposed height of the conical teeth on the same circumference 10 of the drill bit is greater than that of the spherical teeth. Therefore, the main method is to rely on the impact of the conical teeth to break the rock, while the spherical teeth serve to buffer and protect the drill bit, preventing the conical teeth from being overloaded and damaged due to excessive impact load or the alternating soft and hard strata.

[0037] Because the hot dry rock reservoir section contains almost no fluid, there is no need to consider balancing formation pressure, and low-density foam drilling fluid is used for drilling, with negligible drilling fluid loss. After the hot dry rock well is drilled, the fracturing string 12 is run in, and the appropriate number of fracturing stages is selected based on the reservoir's thermal energy distribution characteristics. According to the construction plan, packers 13 are installed at appropriate positions on the fracturing string. Subsequently, fracturing fluid 15 is injected through the fracturing pump set 14. Because multiple microcracks have already been generated in the wellbore during drilling, the corresponding fracturing initiation pressure can be significantly reduced. On the other hand, due to the multiple microcracks induced during drilling, the fractures can initiate and propagate in multiple directions during fracturing, ultimately forming a volumetric fracture network 16 in the formation, thereby maximizing the extraction of formation heat and preventing premature thermal breakthrough due to a single fracture morphology.

[0038] In summary, this invention ensures safe and efficient integrated drilling and extraction of hot dry rock, fully leveraging the advantages of percussion drilling technology in the hot dry rock extraction process. Compared with existing technologies, this invention represents a significant advancement.

[0039] The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention in any way. Although the present invention has been disclosed above with reference to preferred embodiments, it is not intended to limit the present invention. Any person skilled in the art can make some modifications or alterations to the above-disclosed technical content to create equivalent embodiments without departing from the scope of the present invention. Any simple modifications, equivalent changes, and alterations made to the above embodiments based on the technical essence of the present invention without departing from the scope of the present invention shall still fall within the scope of the present invention.

Claims

1. A method for mining hot dry rock based on integrated percussion drilling and assisted fracturing, characterized in that, Includes the following steps: S1: Prepare the drill bit, which can both break the rock at the bottom of the well and damage the well wall to induce microcracks in the well wall; At least some of the cutting teeth on the outermost ring of the drill bit are inclined away from the central axis of the drill bit, and the tips of the inclined cutting teeth are located outside the outer diameter of the drill bit body; the cutting teeth on the inner ring of the drill bit are all arranged in a vertical direction. The outermost cutting teeth of the drill bit include a conical tooth and a spherical tooth, and the conical tooth and the spherical tooth are staggered. The exposed height of the spherical tooth is less than that of the conical tooth. The cutting teeth of the inner ring of the drill bit include two conical teeth and two spherical teeth. The two conical teeth and two spherical teeth of the same inner ring are staggered, and the exposed height of the two spherical teeth is less than the exposed height of the two conical teeth. S2: Determine the structural parameters and percussion drilling parameters of the drill bit using a multi-objective optimization method, specifically including the following sub-steps: S21: Based on the target drilling location and its corresponding engineering design, conduct surface drilling tests on outcrops at different strata to obtain surface drilling test data; S22: Based on the aforementioned ground drilling test data, establish the functional relationships between mechanical drilling rate and drill bit structural parameters and impact drilling parameters (I) and rock breaking efficiency and drill bit structural parameters and impact drilling parameters (II) through data regression analysis. S23: Take a core sample from the wellbore location after drilling the rock sample in step S21, measure its rock strength, and compare it with the original rock strength to obtain the rock strength ratio; the original rock strength is the rock strength at a location far from the wellbore. S24: Establish the functional relationship between the rock strength ratio and the drill bit structural parameters and impact drilling parameters; S25: Uncored rock samples are run into the fracturing string along the wellbore to conduct a surface fracturing test, and the formation initiation pressure is recorded. After the test, the rock samples are cut along the center of the wellbore, and the fractal dimension is used to describe the complexity of the fracture. S26: Establishing the functional relationship between fracture initiation pressure and drill bit structural parameters and percussion drilling parameters; IV. Functional relationship between fracture complexity and drill bit structural parameters and percussion drilling parameters; V. S27: Construct a multi-objective optimization function for mechanical drilling rate, rock breaking efficiency, rock strength ratio, fracture initiation pressure, and fracture complexity based on the functional relationships one through five; the multi-objective optimization function is: Max f(x,y)=[a ROP(x,y),-b MSE(x,y),c USEratio(x,y),-d P(x,y),e FRA(x,y)](1) In the formula: x represents the drill bit structural parameters; y represents the percussion drilling parameters; a, b, c, d, and e are all weighting coefficients; ROP(x,y) is the first functional relationship between mechanical drilling rate and drill bit structural parameters and percussion drilling parameters; MSE(x,y) is the second functional relationship between rock breaking efficiency and drill bit structural parameters and percussion drilling parameters; USEratio(x,y) is the third functional relationship between rock strength ratio and drill bit structural parameters and percussion drilling parameters; P(x,y) is the fourth functional relationship between fracture initiation pressure and drill bit structural parameters and percussion drilling parameters; FRA(x,y) is the fifth functional relationship between fracture complexity and drill bit structural parameters and percussion drilling parameters. S28: Solve the multi-objective optimization function according to the actual situation of the target well to determine the drill bit structure parameters and percussion drilling parameters; S3: Select the optimal drill bit based on the structural parameters determined in step S2, and combine it with the percussion drilling parameters to drill the target well using the percussion drilling method, and carry out fracturing operations on the basis of well wall damage.

2. The method for hot dry rock mining based on integrated percussion drilling and assisted fracturing as described in claim 1, characterized in that, All the cutting teeth on the outermost ring of the drill bit are inclined away from the central axis of the drill bit.

3. The method for dry hot rock mining based on integrated percussion drilling and assisted fracturing as described in claim 1 or 2, characterized in that, The cutting teeth of the drill bit are all PDC teeth.

4. The method for hot dry rock mining based on integrated percussion drilling and assisted fracturing as described in claim 1, characterized in that, In step S22, the rock-breaking efficiency is evaluated by mechanical specific energy.

5. The method for hot dry rock mining based on integrated percussion drilling and assisted fracturing as described in claim 1, characterized in that, When drilling in non-reservoir sections, the weighting coefficients for fracture initiation pressure and fracture complexity are set to 0.

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