A fracturing optimization method, system and medium for preventing pressure channeling in deep shale reservoirs

Abstract

The application discloses a kind of deep shale reservoirs anti-channeling fracturing optimization method, system and medium, belong to shale oil and gas geological exploitation technical field;Including the following steps: obtaining the different scale fracture characteristics and ground stress distribution law of deep shale reservoir;Different scale fracture mechanics parameters and percolation parameter characteristics of rock sample are obtained;By using damage mechanics theory to construct deep shale reservoir multi-physical field coupling fracturing model of matrix characteristics of deep shale reservoir;Based on deep shale reservoir and different scale fracture characteristics, according to solid mechanics, porous medium and Darcy's law, the parameter is set, and the platform pressure numerical model is established;Based on platform pressure numerical model, the optimal fracturing chart affected by multi-scale fracture development is obtained by orthogonal experiment simulation, to determine the maximum effective fracturing volume and avoid interwell channeling of fracturing parameter combination;The application proposes a kind of deep shale reservoir anti-channeling fracturing optimization method, effectively ensures the efficient development of deep shale oil and gas.

Description

TECHNICAL FIELD

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

[0002] The deep shale oil and gas geological development process is facing multiple geological problems such as large burial depth (commonly more than 3500 meters), developed natural fracture network and complex geostress field. The current shale gas development widely adopts cluster well group deployment mode. In the fracturing construction process, the coupling of well spacing, fractures and geostress field can easily induce interwell interference effect, which specifically manifests as fracturing fluid channeling (pressure channeling) and casing deformation (casing deformation) and other engineering accidents. Taking the Lu 203 well area as an example, the casing deformation rate is as high as 68.6%, which shows that the problem of casing failure of unfractured wells caused by pressure channeling of adjacent wells has seriously restricted the large-scale development of deep shale gas and directly affected the single well production and production rhythm of the block.

[0003] The existing technical system has significant limitations. The traditional research separates the geological analysis and engineering design, and simply adopts the conservative scheme of avoiding faults or reducing pump injection displacement, construction pressure and other parameters, which cannot fundamentally solve the pressure channeling problem and will cause insufficient reservoir reconstruction due to insufficient fracturing scale, resulting in production decline. This "passive defense" mode actually sacrifices the quality of fracturing construction, and it is difficult to balance the contradiction between safe operation and efficient development, and it is urgent to establish a geological-engineering integrated collaborative research system. SUMMARY

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

[0005] To solve the above technical problems, the embodiment of the present application provides a fracturing optimization method for preventing pressure channeling in deep shale reservoirs, which comprises the following steps:

[0006] Obtain the different scale fracture characteristics and geostress distribution law of the deep shale reservoir; test the different scale fracture mechanics parameters and seepage parameter characteristics of the rock sample, and the rock sample is collected according to the different scale fracture characteristics of the deep shale reservoir outcrop;

[0007] Based on the matrix rock mechanics characteristics, seepage characteristics and fracturing parameters of the deep shale reservoir, a multi-field coupling control equation including solid equation, seepage equation, damage model and permeability evolution equation is constructed based on damage mechanics theory, and a multi-physical field coupling fracturing model is established by a finite element method;

[0008] Based on the multi-physical field coupling fracturing model, according to the different scale fracture characteristics and the ground stress distribution law of the deep shale reservoir, and the different scale fracture mechanics parameters and the percolation parameter characteristics of the rock sample data, the parameters are set according to the solid mechanics, porous medium and Darcy's law, and the platform pressure numerical model is established;

[0009] Based on the platform pressure numerical model, the optimal fracturing chart affected by the multi-scale fracture development is obtained through orthogonal experiment simulation, so as to determine the fracturing parameter combination which can maximize the effective fracturing volume and avoid interwell channeling.

[0010] In some optional embodiments, the different scale fracture characteristics and the ground stress distribution law of the deep shale reservoir are obtained, specifically including:

[0011] Through the observation of the outcrop, core and thin section of the deep shale reservoir, the opening, filling state, occurrence element and scale distribution characteristics of the different scale fractures of the deep shale reservoir are obtained;

[0012] The geological model of the deep shale reservoir is established by using the well-seismic fusion technology, the ground stress distribution law of the deep shale reservoir is obtained by the geomechanical analysis of the deep shale reservoir combined with the evolution law of the multi-stage tectonic movement of the deep shale reservoir.

[0013] In some optional embodiments, the different scale fracture mechanics parameters and the percolation parameter characteristics of the rock sample are tested, specifically including:

[0014] The process of testing the different scale fracture mechanics parameters of the rock sample is as follows: nanoindentation experiment is carried out on the rock sample of different parts of the fracture to obtain the rock mechanics characteristics of different parts of the fracture; the digital core model of the rock sample is constructed based on the fracture rock mechanics characteristics; the triaxial compression experiment is carried out on the digital core model of the rock sample to obtain the different scale fracture mechanics parameters;

[0015] The process of testing the percolation parameter characteristics of the rock sample is as follows: displacement test is carried out on the rock sample under standard pressure conditions to obtain the percolation parameter characteristics of the rock sample.

[0016] In some optional embodiments, the multi-physical field coupling fracturing model also needs to verify the accuracy of the multi-physical field coupling fracturing model, specifically including:

[0017] The discrete element model is used to verify the accuracy of the multi-physical field coupling fracturing model of the deep shale reservoir.

[0018] In some optional embodiments, the optimal fracturing chart affected by the multi-scale fracture development is obtained based on the platform pressure numerical model through orthogonal experiment simulation, specifically including:

[0019] Based on the platform pressure numerical model, the orthogonal experiment considering the horizontal stress difference, the fracture approaching angle and the multi-scale fracture parameters is carried out, the stress related parameters, the fracture characteristic parameters, the fracturing construction parameters and the rock mechanics parameters are analyzed, the optimal fracturing chart affected by the multi-scale fracture development is obtained by analyzing the different combinations of the stress related parameters, the fracture characteristic parameters, the fracturing construction parameters and the rock mechanics parameters on the fracturing damage evolution, the fracture conductivity and the pressure channeling risk index of the platform pressure numerical model.

[0020] In some optional embodiments, the determined fracturing parameter combination maximizes the effective fracturing volume and avoids the interwell pressure channeling, and the fracturing parameters specifically include:

[0021] The fracturing parameters include the following types: perforation cluster spacing, perforation position, pump displacement, pump liquid volume and fracturing section length.

[0022] Embodiments of the present application also provide a computer device, comprising: at least one processor; and a memory in communication connection with 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 perform the deep shale reservoir pressure channeling prevention fracturing optimization method described above.

[0023] Embodiments of the present application also provide a computer readable storage medium storing a computer program, and the computer program can perform the deep shale reservoir pressure channeling prevention fracturing optimization method described above when executed by a processor.

[0024] The deep shale reservoir pressure channeling prevention fracturing method provided by the present application has at least the following beneficial effects:

[0025] The present application breaks the limitations of traditional geological and engineering research by integrating the multi-scale fracture characteristics of deep shale reservoirs, the ground stress distribution and the rock mechanics and seepage parameters, establishes a multi-physical field coupling fracturing model and a platform pressure numerical model verified by a discrete element model based on damage mechanics theory, generates an optimal fracturing chart through orthogonal experiment simulation, accurately determines the parameter combination of perforation cluster spacing, pump displacement and the like, ensures the maximum effective fracturing volume, slows down or avoids interwell pressure channeling and reduces casing deformation risk, balances safe operation and efficient development, and provides technical support for efficient and large-scale development of deep shale gas. BRIEF DESCRIPTION OF DRAWINGS

[0026] The accompanying drawings, which are included to provide a further understanding of the application and are incorporated in and constitute a part of this application, illustrate embodiments of the application and together with the description serve to explain the application. In the drawings:

[0027] Figure 1 is a flowchart of a deep shale reservoir pressure channeling prevention fracturing method according to an embodiment of the present application;

[0028] Figure 2 is a schematic diagram of a discrete element model and a shale reservoir multi-physical field coupling fracturing model comparison result provided according to an embodiment of the present application;

[0029] Figure 3 is a schematic diagram of a mesoscale fracture provided according to an embodiment of the present application;

[0030] Figure 4 is a schematic diagram of a 75°-approximating mesoscale fracture fracturing damage evolution simulation provided according to an embodiment of the present application;

[0031] Figure 5 is a fracture development type shale reservoir artificial fracture and multi-scale natural fracture or fault interaction mechanism chart provided according to an orthogonal test scheme of the present application;

[0032] Figure 6 is a schematic diagram of an A platform numerical model provided according to an embodiment of the present application;

[0033] Figure 7 is a comparison chart of A platform different fracturing parameter damage results provided according to an embodiment of the present application;

[0034] Figure 8 is a comparison chart of wellbore and upper end point fluid pressure increase under different injection times of an A platform provided according to an embodiment of the present application;

[0035] Figure 9 is a comparison chart of fracture activation length and stress direction deflection under different injection times of an A platform provided according to an embodiment of the present application. DETAILED DESCRIPTION

[0036] In order to make the objectives, technical solutions and advantages of the present application clearer, the technical solutions of the present application will be described below in detail with specific embodiments of the present application and corresponding drawings. Obviously, the described embodiments are only some of the embodiments of the present application, but not all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative labor fall within the scope of protection of the present application.

[0037] An embodiment of the present application relates to a deep shale reservoir pressure channeling prevention fracturing optimization method, and implementation details of the deep shale reservoir pressure channeling prevention fracturing optimization method of the embodiment will be described in detail below. The following content is only provided for the implementation details for the convenience of understanding, and is not necessary for implementing the present solution.

[0038] The specific process of the deep shale reservoir pressure channeling prevention fracturing optimization method of the embodiment can be as followsFigure 1 As shown, comprising:

[0039] Taking the Wufeng-Longmaxi Formation (buried depth greater than 3500m) in Luzhou area in the southern Sichuan Basin as an example, the present patent selects A platform as a typical channeling research object, and the work area where the platform is located is W work area. Due to the influence of multiple tectonic movements, the reservoir fractures and cracks are developed, and the stress condition is complex. In the process of fracturing construction, there are a large number of channeling phenomena, which seriously affect the production rhythm. The deep shale reservoir fracturing optimization method for preventing channeling provided by the present application is used for fracturing, which comprises the following steps.

[0040] Step 101: obtaining different scale crack characteristics and stress distribution law of deep shale reservoir; testing different scale fracture mechanics parameters and percolation parameter characteristics of rock samples, wherein the rock samples are collected according to different scale crack characteristics of deep shale reservoir outcrop;

[0041] By observing the outcrop, core and slice of W work area, the opening, filling state, occurrence element and scale distribution characteristics of different scale cracks in W work area are obtained; according to the crack development scale, the cracks in W work area are divided into three scales of large, medium and small, and the opening, filling state, occurrence element and scale distribution characteristics of various scale cracks are counted. Based on seismic data, drilling, logging, well logging and core observation data are used as auxiliary, a crack model of W work area is established by multi-source data fusion, so as to clarify the cross relationship of multi-scale cracks in the work area.

[0042] The well-seismic fusion technology is used to establish the geological model of W work area, and the stress distribution law of W work area is obtained by geomechanical analysis of W work area combined with the evolution law of multiple tectonic movements of W work area.

[0043] The cracks in W work area have cross-scale similarity, according to geometry and actual application of oil field, the cracks in W work area are divided into three scales of large, medium and small according to the length of the cracks. Taking a standard rock sample (diameter 25mm, height 50mm) in the laboratory as an example, triaxial compression experiment is carried out on the sample, and it is found that the length of small scale cracks is between 2-5mm, which is distributed dispersedly and has no obvious directionality. The medium scale cracks are the product of aggregation of small scale cracks, and the length is between 5-10mm. The large scale cracks have stable direction length and reach a certain length (>10mm), which belong to conjugate joint branches consistent with the maximum shear stress direction of the rock sample. Therefore, for other research scales, the crack scales in the region are equivalent according to this division mode.

[0044] Rock samples are collected on the outcrop of deep shale reservoir according to different scale crack characteristics, and the fault core is taken as the center origin, the fault core refers to the high strain broken core area in the central part of the fault zone, and equidistant sampling is carried out along the vertical and horizontal directions of the fault strike, and the number of samples in each direction is not less than 5.

[0045] The procedure for testing the different scale fracture mechanics parameters of the rock sample is as follows: the nanoindentation experiment is carried out on the rock sample at different fracture positions to obtain the rock mechanical characteristics at different fracture positions; the digital core model of the rock sample is constructed based on the rock mechanical characteristics at different fracture positions; the triaxial compression experiment is carried out on the digital core model of the rock sample to obtain the different scale fracture mechanics parameters;

[0046] The procedure for testing the seepage parameter characteristics of the rock sample is as follows: the artificial fracture is manufactured on the rock sample by wire cutting to obtain the experimental sample with different scale fractures. The obtained experimental sample is placed in a drying oven, the temperature is set to 60 degrees, and dried for 72 hours to remove the errors caused by wire cutting and other factors. The displacement test is carried out on the rock sample under standard pressure conditions to obtain the seepage parameter characteristics of the rock sample.

[0047] Step 102: Based on the damage mechanics theory, the multi-field coupling control equation including the solid equation, the seepage equation, the damage model and the permeability evolution equation is constructed by the deep shale reservoir matrix rock mechanical characteristics, the seepage characteristics and the fracturing parameters, and the multi-physical field coupling fracturing model is established by the finite element method;

[0048] The solid equation is as follows:

[0049] ;

[0050] In the formula, is the effective stress tensor of the rock skeleton, MPa; is the strain tensor; G is the shear modulus of the rock, MPa; is the Poisson's ratio of the rock; is the volumetric strain; is the Kronecker symbol; a is the coefficient of the effective stress of the Biot; is the pore pressure, MPa.

[0051] The solid mechanics equation describes the deformation of the rock under the mechanical load, the pore pressure p and the temperature T, and the stress balance equation is combined to ensure the mechanical balance; the stress balance equation is as follows:

[0052] ;

[0053] In the formula, is the stress tensor, MPa; is the body force tensor, MPa.

[0054] The seepage field describes the flow of fracturing fluid through the Darcy law, and the seepage field equation is as follows:

[0055] ;

[0056] wherein, is the permeability (fracture and matrix are denoted as and ), m2; is the dynamic viscosity of the fluid, mPa·s. In addition, the storage behavior is controlled by the following factors:

[0057] 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:

[0058] ;

[0059] ;

[0060] wherein, and are the ultimate elastic tensile and compressive strains, dimensionless; and are the tensile and compressive strengths, MPa; and are the residual tensile and compressive strengths, MPa; is the residual strength ratio; and are the internal variables in the tensile and compressive conditions, dimensionless.

[0061] The fluid-structure coupling in the model not only considers the influence of rock deformation on the pore pressure, but also considers the change of permeability due to rock damage. The permeability equation of the rock matrix after damage is as follows:

[0062] ;

[0063] wherein, is the initial matrix permeability, m2; is the damage permeability correlation coefficient, which can be estimated as , dimensionless. h is the damage zone width, i.e. approximately equal to the local element size in numerical simulation, m.

[0064] A multi-physical field coupled fracturing test model is established on the A platform, and the model size is 1 m x 1 m, and the total number of element grids is 39180. The accuracy of the shale fracturing numerical model is verified, and the discrete element model is used for model interaction verification, and the results are shown in Figure 2 , which shows that the discrete element simulation results of the homogeneous formation and the multi-physical field coupling results based on damage mechanics are in good agreement in terms of fracture morphology; the change characteristics of the fracturing crack length under liquid injection and the error rate of the classical model are within 15%, indicating that the established fracturing model has good reliability.

[0065] Step 103: Based on the multi-physical field coupling fracturing model, according to the different scale fracture characteristics and stress distribution law of deep shale reservoir, and the different scale fracture mechanics parameters and seepage parameters characteristics of rock sample data, the platform pressure numerical model is established according to the parameters set by solid mechanics, porous medium and Darcy's law;

[0066] Based on solid mechanics, porous medium and Darcy's law, the platform pressure numerical model is established by using the matrix rock mechanics characteristics, seepage characteristics and fracturing parameters of deep shale reservoir. The basic parameters of the platform pressure numerical model are set as shown in Table 1. The fracturing damage numerical model calculation is carried out by using superhydrostatic pressure, and the model formation pressure is 0 MPa, and the effective stress of the boundary condition is the original stress minus the formation pressure.

[0067] Table 1

[0068]

[0069] Step 104: Based on the platform pressure numerical model, the optimal fracturing chart affected by multi-scale fracture development is obtained by orthogonal experiment simulation, so as to determine the fracturing parameter combination which can maximize the effective fracturing volume and avoid interwell channeling.

[0070] Based on the platform pressure numerical model, the orthogonal experiment considering the horizontal stress difference, fracture approaching angle and multi-scale fracture parameters is carried out. By analyzing the different combinations of stress related parameters, fracture characteristic parameters, fracturing construction parameters and rock mechanics parameters on the platform pressure numerical model fracturing damage evolution, fracture conductivity and channeling risk index, the optimal fracturing chart affected by multi-scale fracture development is obtained. The fracturing parameters include the following types: perforation cluster spacing, perforation position, pump displacement, pump liquid volume and fracturing section length.

[0071] The different scale fracture mechanics and seepage properties of W work area are assigned as shown in Table 2. The table classifies the fractures into three categories of small, medium and large according to the scale, and presents the seepage and mechanics parameters under different scales.

[0072] Table 2

[0073]

[0074] Taking the medium scale fracture as an example, the medium scale fracture is as shown in Figure 3 The fracture approaching angle is set to 75° and the stress difference is 0 MPa. The approaching angle 75° medium scale fracture fracturing damage evolution simulation is as shown in Figure 4As shown in the figure, it is shown that the fracture of the fracture along the wellbore is complex, the natural fracture is activated after the fracture, the pore pressure and seepage velocity in the fracture are maximum, the fracture generates greater disturbance stress at the fracture tip, and the fractures interfere with each other and extend. When the artificial fracture meets the natural fracture, the natural fracture is activated, and the artificial fracture fails to expand through the natural fracture. With the continuous flow of fluid into the natural fracture, the length of the activated natural fracture is increasing until it is fully activated. The fracture development type shale reservoir artificial fracture and multi-scale natural fracture or fracture interaction mechanism chart provided by the orthogonal test scheme is as follows Figure 5 As shown in the figure, the interaction of fractures of different scales with artificial fractures under different stress differences and approaching angles is shown.

[0075] Well W platform A develops large-scale fractures. Considering the actual fracture development of platform A, the optimal fracturing chart of platform A is established, and the optimal fracturing chart of platform A is as follows Figure 6 As shown in the figure, the damage results of different fracturing parameters of platform A are compared as follows Figure 7 As shown in the figure, the influence of different fracturing parameters on the fracture expansion in the fracturing operation of platform A is shown. The upper row is the fracture extension between the fracturing well and the adjacent well under different approaching angles (21°, 49°, 72°), and it can be seen that the approaching angle change will affect the fracture shape; the lower row is the fracture expansion difference of the reservoir containing large fractures when different scale liquid volumes (small scale, medium scale, large scale) are used, and the liquid volume scale affects the fracture development degree, which can assist in studying the fracturing parameter optimization and fracture control law. The comparison results of the fluid pressure increase at the wellbore and the upper end of the fracture under different injection times of platform A are as follows Figure 8 As shown in the figure, from the change of fluid pressure, with the fracturing injection, the fluid pressure at the fracturing injection position in the reservoir presents a linear increase trend as a whole, and the fluid pressure at the wellbore increases by 21.3 MPa after 1 h of injection; for the fracture system, although there is damage phenomenon in the fracture due to the influence of the disturbance stress field, it is not activated and is in a gradual instability state, and the fluid pressure presents a linear increase trend as a whole; when the fracturing fracture communicates with the fracture and activates the reference position point, the fluid pressure in the fracture presents a sharp increase phenomenon. The fluid pressure at the reference point far from the fracture presents a linear then exponential growth trend with the fracturing injection, and the fluid pressure at the upper end of the fracture increases by 9 MPa after 1 h of injection. The comparison results of the fracture activation length and stress direction deflection under different injection times of platform A are as follows Figure 9The early process of the fracturing injection is shown from the fracture activation length and the stress field change, although the fracturing fracture does not directly communicate with the fault, the fault has a significant activation length in the stress field disturbance, the activation length is 7.8 m in 5 min injection; the fault activation length growth rate gradually slows down in the middle and late stage of the fracturing, the activation length is close to the maximum length of the fault, the activation length increases to 27.8 m in 20 min injection, and the activation length reaches 36.6 m in 60 min injection. The minimum principal stress direction of the artificial crack tip is extracted for analysis, the deflection angle shows a linear increasing trend with the injection volume, the minimum principal stress direction deflects 8.7° in 5 min injection, the direction deflects 22.9° after 20 min injection, and the direction deflects 52.3° after 60 min injection, which also causes the path deflection phenomenon of the single-stage multi-cluster competitive fracturing expansion.

[0076] The step division of the above various methods is only for clear description, and can be combined into one step or split into multiple steps in implementation, as long as the same logical relationship is included, and all are within the protection scope of the present application; adding insignificant modifications or introducing insignificant designs in the algorithm or flow, but not changing the core design of the algorithm and flow are within the protection scope of the present application.

[0077] Another embodiment of the present application relates to a computer readable storage medium storing a computer program. The computer program is executed by a processor to implement the above method embodiments.

[0078] That is, those skilled in the art can understand that all or part of the steps of the above-mentioned embodiment methods can be completed by programs instructing related hardware, the programs are stored in a storage medium, and include a plurality of instructions for making a device (which can be a single-chip microcomputer, a chip, etc.) or a processor execute all or part of the steps of the method described in each embodiment of the present application. The foregoing storage medium includes: a U disk, a mobile hard disk, a read-only memory (Read-Only Memory, ROM for short), a random access memory (Random Access Memory, RAM for short), a magnetic disk or an optical disk and various program code storage media.

[0079] Those skilled in the art can understand that the above embodiments are specific embodiments for implementing the present application, and in actual application, various changes can be made in form and details without departing from the spirit and scope of the present application.

Claims

1. A fracturing optimization method for preventing hydraulic channeling in deep shale reservoirs, characterized in that, The method includes: To obtain the characteristics of fractures at different scales and the distribution of geostress in deep shale reservoirs; to test the fracture mechanical parameters and seepage parameters of rock samples at different scales, wherein the rock samples were collected according to the fracture characteristics of different scales in the field outcrops of deep shale reservoirs; Based on the matrix rock mechanics characteristics, seepage characteristics and fracturing parameters of deep shale reservoirs, a multi-field coupled control equation is constructed, including solid equation, seepage equation, damage model and permeability evolution equation, and a multi-physics coupled fracturing model is established by the finite element method. Based on the multiphysics field coupled fracturing model, according to the characteristics of fractures at different scales and the distribution of geostress in deep shale reservoirs, as well as the characteristics of fracture mechanical parameters and seepage parameters at different scales of rock samples, 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 chart of the multi-scale fracture development influence is obtained through orthogonal experimental simulation, thereby determining the combination of fracturing parameters that maximizes the effective fracturing volume and avoids inter-well hydraulic cross-flow. The multiphysics coupled fracturing model also needs to be verified for accuracy, specifically including: The accuracy of the multiphysics coupled fracturing model for deep shale reservoirs was verified using a discrete element model. The optimal fracturing chart based on the platform fracturing numerical model, obtained through orthogonal experimental simulation of the multi-scale fracture development influence, specifically includes: Based on the platform fracturing numerical model, orthogonal experiments were conducted 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 construction parameters and rock mechanics parameters on the fracturing damage evolution, fracture conductivity and pressure channeling risk index of the platform fracturing numerical model, the optimal fracturing chart of the influence of multi-scale fracture development was obtained.

2. The fracturing optimization method for preventing hydraulic channeling in deep shale reservoirs as described in claim 1, characterized in that, The acquisition of fracture characteristics and in-situ stress distribution patterns at different scales in deep shale reservoirs specifically includes: By observing outcrops, cores, and thin sections of deep shale reservoirs, we can obtain the aperture, filling state, occurrence elements, and scale distribution characteristics of fractures at different scales in deep shale reservoirs. A geological model of deep shale reservoirs was established using well-seismic fusion technology. By combining the evolution of multi-stage tectonic movements in deep shale reservoirs and conducting geomechanical analysis, the distribution law of geostress in deep shale reservoirs was obtained.

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

4. The fracturing optimization method for preventing hydraulic channeling in deep shale reservoirs as described in claim 1, characterized in that, The method thereby determines the combination of fracturing parameters that maximizes the effective fracturing volume and avoids inter-well hydraulic channeling. These fracturing parameters specifically include: Fracturing parameters include the following types: perforation cluster spacing, perforation location, pump flow rate, pump fluid volume, and fracturing section length.

5. 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, the instructions being executed by the at least one processor to enable the at least one processor to perform the fracturing optimization method for preventing cross-flow in deep shale reservoirs as described in any one of claims 1 to 4.

6. A computer-readable storage medium, characterized in that, The computer-readable storage medium stores a computer program, which, when executed by a processor, is capable of performing any one of the fracturing optimization methods for preventing cross-flow in deep shale reservoirs as defined in claims 1 to 4.

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