Fracturing optimization method and system for preventing pressure channeling of deep shale reservoir and medium

Abstract

The invention discloses a fracturing optimization method and system for preventing pressure channeling of a deep shale reservoir and a medium, and belongs to the technical field of shale oil and gas geological exploitation. Comprising the following steps: acquiring different-scale fracture characteristics and ground stress distribution rules of a deep shale reservoir; different-scale fracture mechanical parameters and seepage parameter characteristics of the rock sample are obtained; building a deep shale reservoir multi-physics coupling fracturing model by using a damage mechanics theory according to deep shale reservoir matrix characteristics; the method comprises the following steps: setting parameters according to solid mechanics, porous media and Darcy law based on a deep shale reservoir and different-scale fracture characteristics, and establishing a platform fracturing numerical model; on the basis of a platform fracturing numerical model, an optimal fracturing chart influenced by multi-scale fracture development is obtained through orthogonal experimental simulation, so that a fracturing parameter combination enabling the effective fracturing volume to be maximum and avoiding inter-well pressure channeling is determined; according to the fracturing optimization method for preventing pressure channeling of the deep shale reservoir, efficient development of deep shale oil and gas is effectively guaranteed.

Description

Technical Field

[0001] The present invention relates to the technical field of shale oil and gas geological exploitation, and in particular to a fracturing optimization method, system and medium for preventing pressure channeling in deep shale reservoirs. Background Art

[0002] The development of deep shale oil and gas reservoirs faces multiple geological challenges, including deep burial depths (generally exceeding 3,500 meters), a well-developed natural fracture network, and complex geostress fields. Currently, cluster well deployment is widely used in shale gas development. During fracturing, the coupling of well spacing, fractures, and geostress fields can easily induce inter-well interference effects, manifesting as engineering accidents such as fracturing fluid crossflow (fracturing channeling) and casing deformation (casing deformation). For example, the severe casing deformation rate of 68.6% in the Lu 203 well block indicates that casing failure in unfractured wells due to crossflow from neighboring wells has severely hampered the large-scale development of deep shale gas, directly affecting individual well production and the pace of production increases within the block.

[0003] The existing technology system has significant limitations: Traditional research separates geological analysis from engineering design. Simply adopting conservative approaches such as avoiding faults or reducing pumping rates and operating pressures fails to fundamentally address channeling. Furthermore, insufficient fracturing scale leads to inadequate reservoir stimulation and reduced production. This "passive defense" approach effectively compromises fracturing quality and makes it difficult to balance safe operations with efficient development. Therefore, a collaborative, integrated geological and engineering research system is urgently needed. Summary of the Invention

[0004] The purpose of the present invention is to provide a fracturing optimization method, system and medium for preventing pressure channeling in deep shale reservoirs, which can ensure the effective fracturing volume while slowing down or avoiding the problem of pressure channeling between wells.

[0005] To solve the above technical problems, an embodiment of the present invention provides a fracturing optimization method for preventing pressure channeling in deep shale reservoirs, comprising the following steps: Obtain the characteristics of different-scale fractures and the distribution of ground stress in deep shale reservoirs; test the fracture mechanics parameters and seepage parameter characteristics of different-scale rock samples collected according to the characteristics of different-scale fractures in field outcrops of deep shale reservoirs; Based on the rock mechanics characteristics, seepage characteristics and fracturing parameters of deep shale reservoir matrix, a multi-field coupling control equation including solid equation, seepage equation, damage model and permeability evolution equation was constructed based on damage mechanics theory, and a multi-physics field coupling fracturing model was established using the finite element method. Based on the multi-physics coupled fracturing model, according to the different scale fracture characteristics and ground stress distribution law of deep shale reservoirs, as well as the fracture mechanics parameters and seepage parameter characteristics of rock samples at different scales, parameters are set according to solid mechanics, porous media and Darcy's law to establish a platform fracturing numerical model; Based on the platform fracturing numerical model, the optimal fracturing map influenced by multi-scale fracture development was obtained through orthogonal experimental simulation, thereby determining the fracturing parameter combination that maximizes the effective fracturing volume and avoids inter-well pressure channeling.

[0006] In some optional embodiments, obtaining the characteristics of fractures of different scales and the distribution law of in-situ stress in the deep shale reservoir specifically includes: By observing the outcrops, cores and thin sections of deep shale reservoirs, we can obtain the aperture, filling state, occurrence factors and scale distribution characteristics of fractures of different scales in deep shale reservoirs; The well-seismic fusion technology is used to establish a geological model of deep shale reservoirs. Combined with the multi-stage tectonic movement evolution law of deep shale reservoirs, the geostress distribution law of deep shale reservoirs is obtained through geomechanical analysis of deep shale reservoirs.

[0007] In some optional embodiments, the fracture mechanics parameters and seepage parameter characteristics of the tested rock samples at different scales specifically include: The process for testing the fracture mechanics parameters of rock samples at different scales is as follows: nanoindentation experiments are conducted on rock samples at different fracture locations to obtain the rock mechanics characteristics at different fracture locations; a digital core model of the rock sample is constructed based on the fracture rock mechanics characteristics; and triaxial compression experiments are conducted on the digital core model of the rock sample to obtain the fracture mechanics parameters at different scales. The process of testing the seepage parameter characteristics of rock samples is as follows: a displacement test is performed on the rock sample under standard pressure conditions to obtain the seepage parameter characteristics of the rock sample.

[0008] In some optional embodiments, the multi-physics field coupled fracturing model also needs to verify the accuracy of the multi-physics field coupled fracturing model, specifically including: The discrete element model is used to verify the accuracy of the multi-physics field coupling fracturing model for deep shale reservoirs.

[0009] In some optional embodiments, the platform fracturing numerical model is used to simulate the optimal fracturing map for the influence of multi-scale fracture development through orthogonal experiments, specifically including: Based on the platform fracturing numerical model, orthogonal experiments were carried out considering horizontal stress difference, fracture approach angle and multi-scale fracture parameters. By analyzing the effects of different combinations of stress-related parameters, fracture characteristic parameters, fracturing operation parameters and rock mechanics parameters on the fracturing damage evolution, fracture conductivity and pressure channeling risk indicators of the platform fracturing numerical model, the optimal fracturing map that affects the development of multi-scale fractures was obtained.

[0010] In some optional embodiments, the fracturing parameter combination that maximizes the effective fracturing volume and avoids inter-well pressure crosstalk is determined, and the fracturing parameters specifically include: Fracturing parameters include the following types: perforation cluster spacing, perforation location, pumping rate, pumping fluid volume, and fracturing stage length.

[0011] An embodiment of the present invention also provides a computer device, comprising: at least one processor; and a memory communicatively connected to the at least one processor; wherein the memory stores instructions executable by the at least one processor, and the instructions are executed by the at least one processor to enable the at least one processor to execute the above-mentioned fracturing optimization method for preventing pressure channeling in deep shale reservoirs.

[0012] An embodiment of the present invention further provides a computer-readable storage medium storing a computer program. When the computer program is executed by a processor, the computer program can execute the above-mentioned fracturing optimization method for preventing pressure channeling in deep shale reservoirs.

[0013] The deep shale reservoir anti-channeling fracturing method provided by the present invention has at least the following beneficial effects: This invention breaks the limitations of traditional geological and engineering research by integrating the multi-scale fracture characteristics, ground stress distribution, and rock mechanics and seepage parameters of deep shale reservoirs. Based on the damage mechanics theory, a multi-physics field coupled fracturing model and a platform fracturing numerical model verified by the discrete element model are established. The optimal fracturing map is generated through orthogonal experimental simulation, and the combination of parameters such as perforation cluster spacing and pumping displacement is accurately determined. While ensuring the maximum effective fracturing volume, it slows down or avoids inter-well pressure channeling and reduces the risk of casing change, balances safe operation and efficient development, and provides technical support for the efficient and large-scale development of deep shale gas. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] The drawings described herein are used to provide a further understanding of the present invention and constitute a part of the present invention. The exemplary embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute an improper limitation of the present invention. In the drawings: Figure 1 This is a flow chart of a fracturing method for preventing pressure channeling in a deep shale reservoir provided according to one embodiment of the present invention; Figure 2is a schematic diagram of comparison results between a discrete element model and a shale reservoir multi-physics field coupled fracturing model provided according to an embodiment of the present invention; Figure 3 is a schematic diagram of a mesoscale crack provided according to an embodiment of the present invention; Figure 4 1 is a schematic diagram of a simulation of damage evolution of a mesoscale fracture under a 75° approach angle according to an embodiment of the present invention; Figure 5 This is a diagram of the interaction mechanism between artificial fractures and multi-scale natural fractures or faults in a fracture-developed shale reservoir provided by the orthogonal test scheme of the present invention; Figure 6 is a schematic diagram of a numerical model of platform A provided according to one embodiment of the present invention; Figure 7 This is a comparison diagram of damage results of different fracturing parameters on platform A provided according to an embodiment of the present invention; Figure 8 This is a graph comparing the increase in fluid pressure around the well and at the upper end point of the fracture at different injection times on platform A according to one embodiment of the present invention; Figure 9 This is a comparison result diagram of the fracture activation length and stress direction deflection under different injection times of platform A provided according to an embodiment of the present invention. DETAILED DESCRIPTION

[0015] To make the objectives, technical solutions, and advantages of the present invention more clear, the technical solutions of the present invention will be clearly and completely described below in conjunction with specific embodiments of the present invention and corresponding drawings. Obviously, the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0016] One embodiment of the present invention relates to a fracturing optimization method for preventing pressure channeling in deep shale reservoirs. The implementation details of the fracturing optimization method for preventing pressure channeling in deep shale reservoirs of this embodiment are specifically described below. The following content is only the implementation details provided for easy understanding and is not necessary for implementing this solution.

[0017] The specific process of the fracturing optimization method for preventing pressure channeling in deep shale reservoirs of this embodiment can be as follows: Figure 1 As shown, including: Taking the Wufeng-Longmaxi Formation (buried at a depth greater than 3,500 meters) in the Luzhou area of ​​the southern Sichuan Basin as an example, this patent selected Platform A as a typical channeling research target. This platform is located in the W work area. Due to the influence of multiple phases of tectonic movement, reservoir fractures and cracks are well-developed, and stress conditions are complex. During fracturing operations, a large amount of channeling occurs, seriously affecting the production rate. The deep shale reservoir is fractured using the fracturing optimization method for preventing channeling provided by this invention, including the following steps.

[0018] Step 101: Acquire different-scale fracture characteristics and ground stress distribution patterns of deep shale reservoirs; test fracture mechanics parameters and seepage parameter characteristics of rock samples at different scales, wherein the rock samples are collected based on different-scale fracture characteristics of field outcrops of deep shale reservoirs; By observing outcrops, cores, and thin sections in the W Work Area, we determined the aperture, filling state, occurrence characteristics, and scale distribution characteristics of fractures at different scales. Based on the scale of fracture development, we categorized the fractures in the W Work Area into three scales: large, medium, and small. We also analyzed the aperture, filling state, occurrence characteristics, and scale distribution characteristics of each fracture scale. Using seismic data as the primary data source, supplemented by drilling, mud logging, well logging, and core observation data, we developed a fracture model for the W Work Area through multi-source data fusion to clarify the intertwined relationships among fractures at multiple scales within the area.

[0019] The geological model of the W work area was established using well-seismic fusion technology. Combined with the multi-period tectonic movement evolution law of the W work area, the geostress distribution law of the W work area was obtained through geomechanical analysis of the W work area.

[0020] Fractures in the W work area exhibit similarity across scales. Based on geometry and practical oilfield applications, fractures in the W work area are categorized into three scales: large, medium, and small, using fracture length as a metric. For illustration, triaxial compression tests on a standard laboratory rock sample (25 mm diameter, 50 mm height) revealed that small-scale fractures ranged in length from 2 to 5 mm, were dispersed, and lacked significant directionality. Medium-scale fractures, formed by the aggregation of small-scale fractures, ranged in length from 5 to 10 mm. Large-scale fractures exhibit stable directional lengths, reaching a certain length (>10 mm) and belonging to conjugate joint branches aligned with the direction of maximum shear stress in the rock sample. Therefore, for other study scales, this categorization is used to effectively divide regional fracture scales.

[0021] Rock samples are collected on the outcrops of deep shale reservoirs based on the characteristics of fractures of different scales. The fault core is taken as the central origin. The fault core refers to the high-strain fracture core area in the center of the fault zone. Sampling is carried out at equal intervals in the vertical and horizontal directions along the fault direction, with no less than 5 samples in each direction.

[0022] The process for testing the fracture mechanics parameters of rock samples at different scales is as follows: nanoindentation experiments are conducted on rock samples at different fracture locations to obtain the rock mechanics characteristics at different fracture locations; a digital core model of the rock sample is constructed based on the fracture rock mechanics characteristics; and triaxial compression experiments are conducted on the digital core model of the rock sample to obtain the fracture mechanics parameters at different scales. The process for testing the seepage parameter characteristics of rock samples is as follows: Artificial fractures are created in rock samples using wire cutting to obtain experimental samples with fractures of varying sizes. These samples are then placed in a drying oven at 60°C for 72 hours to eliminate errors caused by wire cutting and other factors. Displacement tests are then conducted on the rock samples under standard pressure to determine their seepage parameter characteristics.

[0023] Step 102: Based on the rock mechanics characteristics, seepage characteristics, and fracturing parameters of the deep shale reservoir matrix, a multi-field coupled control equation including a solid equation, a seepage equation, a damage model, and a permeability evolution equation is constructed based on damage mechanics theory, and a multi-physics coupled fracturing model is established using the finite element method. The solid equation is as follows: ; Where, is the effective stress tensor of the rock skeleton, MPa; is the strain tensor; G is the shear modulus of rock, MPa; is the Poisson's ratio of the rock; is the volume strain; is the Kronecker symbol; α is the Biot effective stress coefficient; is the pore pressure, MPa.

[0024] Solid mechanics equations describe the deformation of rock under mechanical load, pore pressure p and temperature T, and are combined with stress equilibrium equations to ensure mechanical equilibrium; the stress equilibrium equation is as follows: ; Where, is the stress tensor, MPa; is the body force tensor, MPa.

[0025] The seepage field is described by Darcy's law to describe the flow of fracturing fluid. The seepage field equation is as follows: ; Where, is the permeability (fracture and matrix are expressed as and ), m2; is the dynamic viscosity of the fluid, mPa·s. In addition, the storage behavior is controlled by the following factors:

[0026] The strain-driven isotropic damage model is used to simulate the damage and failure process of rock materials. The damage parameter equation is as follows: ; ; Where, and are the ultimate elastic tensile strain and compressive strain, respectively, dimensionless; and are tensile strength and compressive strength, MPa, respectively; and are the residual tensile strength and compressive strength, MPa, respectively; is the residual strength ratio; and are dimensionless internal variables for tension and compression conditions, respectively.

[0027] The fluid-solid coupling in the model not only considers the effect of rock deformation on pore pressure, but also considers the change in permeability caused by rock damage. The permeability equation of the damaged rock matrix is ​​as follows: ; Where, is the initial matrix permeability, m2; is the damage permeability correlation coefficient, which can be estimated as , dimensionless. h is the width of the damage zone, which is approximately equal to the local element size in the numerical simulation, m.

[0028] A multi-physics coupled fracturing test model for platform A was established. The model size was 1 m × 1 m, and the number of grid cells was 39,180. The accuracy of the shale fracturing numerical model was verified by using a discrete element model for model interaction verification. The results are shown in the figure below. Figure 2 The figure shows that the fracture morphology of the discrete element simulation results of homogeneous formations is consistent well with the multi-physics field coupling results based on damage mechanics; the error rate of the fracture length change characteristics under liquid injection and the classic model is within 15%, indicating that the constructed fracturing model has good reliability.

[0029] Step 103: Based on the multi-physics coupled fracturing model, according to the characteristics of fractures at different scales and the distribution of ground stress in the deep shale reservoir, as well as the fracture mechanics parameters and seepage parameters of rock samples at different scales, parameters are set based on solid mechanics, porous media, and Darcy's law to establish a platform fracturing numerical model; Based on solid mechanics, porous media, and Darcy's law, a platform fracturing numerical model was established using the rock mechanics and seepage characteristics of deep shale reservoirs and fracturing parameters. The basic parameter settings for the platform fracturing numerical model are shown in Table 1. When using excess hydrostatic pressure to calculate the fracturing damage numerical model, the model formation pressure is 0 MPa, and the effective stress of the boundary condition is the in situ stress minus the formation pressure.

[0030] Table 1

[0031] Step 104: Based on the platform fracturing numerical model, an optimal fracturing map influenced by multi-scale fracture development is obtained through orthogonal experimental simulation, thereby determining a fracturing parameter combination that maximizes the effective fracturing volume and avoids inter-well pressure channeling.

[0032] Based on a platform fracturing numerical model, orthogonal experiments were conducted that considered horizontal stress differences, fracture approach angles, and multi-scale fracture parameters. By analyzing the effects of different combinations of stress-related parameters, fracture characteristic parameters, fracturing operation parameters, and rock mechanics parameters on the fracturing damage evolution, fracture conductivity, and channeling risk indicators of the platform fracturing numerical model, an optimal fracturing diagram was obtained that reflects the influence of multi-scale fracture development. Fracturing parameters include the following: perforation cluster spacing, perforation location, pumping rate, pumping fluid volume, and fracturing stage length.

[0033] The mechanical and seepage properties of fractures at different scales in the W work area are shown in Table 2. This table divides the fractures into three categories: small, medium, and large, and presents the seepage and mechanical parameters at different scales.

[0034] Table 2

[0035] Taking mesoscale cracks as an example, mesoscale cracks such as Figure 3 As shown in the figure, the fracture approach angle is set to 75° and the stress difference is 0 MPa. The simulation of the damage evolution of the mesoscale fracture under the approach angle of 75° is as follows: Figure 4 As shown in the figure, it shows that the fractures along the wellbore are complex. After the natural fractures are activated, the pore pressure and seepage velocity in the fracture are the largest. The fractures generate greater disturbance stress at the fracture tips, which interfere with each other's expansion and extension. When the artificial fractures meet the natural fractures, the natural fractures are activated, and the artificial fractures fail to penetrate the natural fractures to expand. As the fluid continues to flow into the natural fractures, the length of the activated natural fractures continues to increase until it is fully activated. The orthogonal experimental scheme provides a diagram of the interaction mechanism between artificial fractures and multi-scale natural fractures or faults in the fracture-developed shale reservoir as shown in the figure. Figure 5 As shown in the figure, the interaction between fractures of different scales and artificial cracks under different stress differences and approach angles is demonstrated.

[0036] The A platform in the W well area has large-scale fractures. Considering the actual fracture development of the A platform, the optimal fracturing diagram of the A platform is established. The optimal fracturing diagram of the A platform is as follows: Figure 6 As shown in the figure, the damage results of different fracturing parameters on platform A are compared. Figure 7 As shown in the figure, the effect of different fracturing parameters on fracture expansion during the fracturing operation of platform A is shown. The upper row shows the fracture extension between the fracturing well and the adjacent well at different approach angles (21°, 49°, 72°). It can be seen that the change of approach angle will affect the fracture morphology; the lower row shows the difference in fracture expansion in the reservoir containing large faults when different scales of liquid volume (small scale, medium scale, large scale) are applied. The scale of liquid volume affects the degree of fracture development, which can assist in the study of fracturing parameter optimization and fracture control rules. The comparison results of the fluid pressure increase around the well and the upper end point of the fracture at different injection times on platform A are shown in the figure. Figure 8 As shown in the figure, from the perspective of fluid pressure changes, as the fracturing pumping progresses, the fluid pressure at the fracturing pumping position in the reservoir shows an overall linear increasing trend. After 1 hour of injection, the fluid pressure around the well increases by 21.3 MPa. For the fracture system, when the injection scale is small at the beginning of the fracturing, although there is damage inside the fracture due to the influence of the disturbed stress field, it is not activated and is in a gradually unstable state. The fluid pressure shows an overall linear increasing trend. When the fracturing crack connects the fracture and activates the reference position point, its internal fluid pressure shows a steep increase. The fluid pressure at the reference point at the far end of the fracture shows a linear and then exponential growth trend with the fracturing injection. After 1 hour of injection, the fluid pressure at the upper end point of the fracture increases by 9 MPa. The comparison results of the fracture activation length and stress direction deflection under different injection times on the A platform are shown in the figure. Figure 9 The figure shows the changes in fracture activation length and stress field. During the early stages of fracturing injection, although the fractures do not directly connect to the fault, the stress field perturbs the fault, which already has a significant activation length. The activation length reaches 7.8 m after 5 minutes of injection. During the middle and late stages of fracturing, the growth rate of the fault activation length gradually slows, and the activation length approaches the maximum length of the fault. After 20 minutes of injection, the activation length increases to 27.8 m, and after 60 minutes of injection, the activation length reaches 36.6 m. The minimum principal stress direction at the tip of the artificial fracture was extracted and analyzed. The deflection angle increases linearly with the injection rate. The minimum principal stress direction deflects by 8.7° after 5 minutes of injection, 22.9° after 20 minutes of injection, and 52.3° after 60 minutes of injection. This also triggers the path deflection phenomenon of competitive fracturing expansion in a single segment with multiple clusters.

[0037] The steps of the various methods above are divided only for the purpose of clear description. When implemented, they can be combined into one step or some steps can be split and decomposed into multiple steps. As long as they include the same logical relationship, they are within the scope of protection of the present invention. Adding insignificant modifications or introducing insignificant designs to the algorithm or process without changing the core design of the algorithm and process are all within the scope of protection of the invention.

[0038] Another embodiment of the present invention relates to a computer-readable storage medium storing a computer program, which implements the above method embodiment when executed by a processor.

[0039] That is, those skilled in the art will understand that all or part of the steps in the above-described method embodiments can be implemented by instructing the relevant hardware through a program. The program is stored in a storage medium and includes a number of instructions for causing a device (such as a microcontroller or chip) or a processor to execute all or part of the steps in the method embodiments of the present invention. The aforementioned storage medium includes various media capable of storing program code, such as a USB flash drive, a mobile hard drive, a read-only memory (ROM), a random access memory (RAM), a magnetic disk, or an optical disk.

[0040] Those skilled in the art will appreciate that the above embodiments are specific embodiments for implementing the present invention, and that in actual applications, various changes may be made thereto in form and detail without departing from the spirit and scope of the present invention.

Claims

1. A fracturing optimization method for preventing pressure channeling in deep shale reservoirs, characterized in that: The method comprises: Obtain the characteristics of different-scale fractures and the distribution of ground stress in deep shale reservoirs; test the fracture mechanics parameters and seepage parameter characteristics of different-scale rock samples collected according to the characteristics of different-scale fractures in field outcrops of deep shale reservoirs; Based on the rock mechanics characteristics, seepage characteristics and fracturing parameters of deep shale reservoir matrix, a multi-field coupling control equation including solid equation, seepage equation, damage model and permeability evolution equation was constructed based on damage mechanics theory, and a multi-physics field coupling fracturing model was established using the finite element method. Based on the multi-physics coupled fracturing model, according to the different scale fracture characteristics and ground stress distribution law of deep shale reservoirs, as well as the fracture mechanics parameters and seepage parameter characteristics of rock samples at different scales, parameters are set according to solid mechanics, porous media and Darcy's law to establish a platform fracturing numerical model; Based on the platform fracturing numerical model, the optimal fracturing map influenced by multi-scale fracture development was obtained through orthogonal experimental simulation, thereby determining the fracturing parameter combination that maximizes the effective fracturing volume and avoids inter-well pressure channeling.

2. The fracturing optimization method for preventing pressure channeling in deep shale reservoirs according to claim 1, characterized in that: The method of obtaining the different scale fracture characteristics and in-situ stress distribution patterns of the deep shale reservoir specifically includes: By observing the outcrops, cores and thin sections of deep shale reservoirs, we can obtain the aperture, filling state, occurrence factors and scale distribution characteristics of fractures of different scales in deep shale reservoirs; The well-seismic fusion technology is used to establish a geological model of deep shale reservoirs. Combined with the multi-stage tectonic movement evolution law of deep shale reservoirs, the geostress distribution law of deep shale reservoirs is obtained through geomechanical analysis of deep shale reservoirs.

3. The fracturing optimization method for preventing pressure channeling in deep shale reservoirs according to claim 1, characterized in that: The fracture mechanics parameters and seepage parameter characteristics of the tested rock samples at different scales specifically include: The process for testing the fracture mechanics parameters of rock samples at different scales is as follows: nanoindentation experiments are conducted on rock samples at different fracture locations to obtain the rock mechanics characteristics at different fracture locations; a digital core model of the rock sample is constructed based on the fracture rock mechanics characteristics; and triaxial compression experiments are conducted on the digital core model of the rock sample to obtain the fracture mechanics parameters at different scales. The process of testing the seepage parameter characteristics of rock samples is as follows: a displacement test is performed on the rock sample under standard pressure conditions to obtain the seepage parameter characteristics of the rock sample.

4. The fracturing optimization method for preventing pressure channeling in deep shale reservoirs according to claim 1, characterized in that: The multi-physics coupled fracturing model also needs to be verified for its accuracy, specifically including: The discrete element model is used to verify the accuracy of the multi-physics field coupling fracturing model for deep shale reservoirs.

5. The fracturing optimization method for preventing pressure channeling in deep shale reservoirs according to claim 1, characterized in that: The optimal fracturing map based on the platform fracturing numerical model and the orthogonal experimental simulation of the multi-scale fracture development effect are obtained, specifically including: Based on the platform fracturing numerical model, orthogonal experiments were carried out considering horizontal stress difference, fracture approach angle and multi-scale fracture parameters. By analyzing the effects of different combinations of stress-related parameters, fracture characteristic parameters, fracturing operation parameters and rock mechanics parameters on the fracturing damage evolution, fracture conductivity and pressure channeling risk indicators of the platform fracturing numerical model, the optimal fracturing map that affects the development of multi-scale fractures was obtained.

6. The fracturing optimization method for preventing pressure channeling in deep shale reservoirs according to claim 1, characterized in that: The fracturing parameter combination that maximizes the effective fracturing volume and avoids inter-well pressure channeling is determined in this way. The fracturing parameters specifically include: Fracturing parameters include the following types: perforation cluster spacing, perforation location, pumping rate, pumping fluid volume, and fracturing stage length.

7. A computer system, characterized in that: include: at least one processor; And, a memory communicatively connected to the at least one processor; wherein the memory stores instructions executable by the at least one processor, and the instructions are executed by the at least one processor to enable the at least one processor to execute the deep shale reservoir anti-pressure channeling fracturing optimization method as described in any one of claims 1 to 6.

8. A computer-readable storage medium, characterized in that The computer-readable storage medium stores a computer program, and when the computer program is run by a processor, it can execute any one of the fracturing optimization methods for preventing pressure channeling in deep shale reservoirs defined in claims 1 to 6.

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