Fractal feature-based far-field temporary plugging mixing system and determination method thereof

Abstract

The invention discloses a far-field temporary plugging mixed system based on fractal characteristics and a determination method thereof. The determination method comprises the following steps: acquiring a pore structure fractal dimension of a target small layer and fractal dimensions of different temporary plugging mixed systems; the pore structure fractal dimension of the target small layer is obtained through the representative core of the target small layer in the target layer; fractal dimensions of different temporary plugging mixed systems are obtained through a model of cumulative granularity and granularity radius; and then determining a far-field temporary plugging mixed system according to the fractal dimension of the pore structure of the target layer and the fractal dimensions of different temporary plugging mixed systems. According to the method, the optimal temporary plugging system is determined by comparing the fractal dimension of the pore structure of a target small layer with the fractal dimensions of different temporary plugging mixed systems, a certain amount of softening particles and elastic particles are added into rigid bridging particles, the plugging effect is enhanced, the far-field temporary plugging technology is better applied, and the temporary plugging effect is improved. The soluble temporary plugging agent and the proppant are optimally matched, and the temporary plugging effect is not weakened due to the addition of the proppant.

Description

Technical Field

[0001] The invention belongs to the technical field of tight sandstone reservoir production enhancement and transformation measures, and relates to a far-field temporary plugging mixed system based on fractal characteristics and a determination method thereof. Background Art

[0002] The conventional temporary plugging and diversion fracturing method is to inject temporary plugging agents during the fracturing process to temporarily plug the cracks, force the cracks to turn and extend, and form new cracks. Thus, a complex fracture network system is formed, the fracture drainage area is increased, and the purpose of increasing production is achieved. The currently commonly used temporary plugging agents use particles of different sizes to accumulate in the pores, or form filter cakes through gelling operations, thereby forming a temporary plugging barrier layer with extremely low permeability and high pressure resistance, achieving crack plugging and diversion and extension of the cracks. The filling method is generally to stop the pump and fill from the sand mixer.

[0003] In 2016, Gomaa introduced a far-field temporary plugging and diversion technology, which uses a mixture of soluble solid particles and proppants to effectively plug the far end of the fracture and maintain the conductivity of the fracture after the soluble material dissolves. Far-field temporary plugging and diversion requires plugging the inside of the fracture, increasing the pressure inside the fracture, opening up natural fractures to produce branch fractures, and ultimately forming a complex fracture network. Normally, temporary plugging and diversion agents can plug the inside of the fracture, produce a tight plugging layer, and force subsequent fluids to flow to the untransformed layer. However, if proppants are not added to the diversion agent, the fracture will close and lose its conductivity as the temporary plugging and diversion agent dissolves. This method is more convenient and faster than the conventional fracturing process of adding sand first and then temporarily plugging. It can completely update the traditional temporary plugging process and can be flexibly combined with traditional processes. At present, the materials used in this method are mainly a mixed far-field temporary plugging system of soluble temporary plugging particles and proppant particles.

[0004] Fractal theory is usually used to describe the morphological characteristics of objects that fill space in a non-integer dimensional form. Such objects have self-similarity, that is, a rough or fragmented geometric shape can be divided into several parts, and each part is (at least approximately) a reduced shape of the whole. The rock medium includes mineral particles and pores and cracks at various levels, and each part has fractal characteristics. A large number of studies have also shown that fractal theory can well describe the heterogeneity of objects of different scales. In order to ensure that temporary plugging particles can still have effective temporary plugging ability after mixing with proppant particles, different types of temporary plugging agents can be adapted to proppant particles, and fractal theory is applied to optimize the ratio of temporary plugging particles to fracture end support particles, so as to utilize the key geological parameters of the comprehensive target reservoir and the currently commonly used temporary plugging agents and proppant types, and obtain the optimal ratio of the mixed system through simulation calculation, so as to improve the application efficiency of far-field temporary plugging diversion technology.

[0005] The existing temporary plugging and diversion fracturing uses temporary plugging and diversion materials of different sizes to temporarily plug the cracks in the fractures, plugging the cracks of different sizes formed by the first fracturing. The controllability is weak, so the crack extension pressure does not increase much, the crack diversion extension is not obvious, and it is not easy to form diversion cracks. Therefore, the far-field temporary plugging technology is adopted, and the far-field temporary plugging agent with finer particle size is used to form the fracture end plugging and the fracture surface mud cake to improve the temporary plugging success rate. The far-field temporary plugging needs to be matched with proppants, and the temporary plugging performance may be weakened with the addition of proppants. Therefore, it is necessary to maximize the heterogeneity of the pore structure of the temporary plugging system composed of the temporary plugging agent and proppants based on the fractal characteristics, and to achieve efficient temporary plugging and open the fracture network.

[0006] However, the existing far-field temporary plugging mixed system determined by fractal theory uses a single specification of temporary plugging agent, which is difficult to meet the ideal filling requirements and cannot adapt to the changes in the crack closure pressure. The plugging layer is prone to instability and damage. Summary of the invention

[0007] In view of the problems existing in the prior art, the present invention provides a far-field temporary plugging mixed system based on fractal characteristics and a determination method thereof, thereby solving the problems that the existing temporary plugging agent system is single and the temporary plugging effect is not ideal.

[0008] The present invention is achieved through the following technical solutions:

[0009] A method for determining a far-field temporary plugging hybrid system based on fractal characteristics comprises the following steps:

[0010] S1: Obtain the fractal dimension of the pore structure of the target sublayer and the fractal dimension of different temporary plugging mixed systems;

[0011] S2: Determine the far-field temporary plugging mixed system through the fractal dimension of the pore structure of the target layer and the fractal dimensions of different temporary plugging mixed systems;

[0012] The fractal dimension of the pore structure of the target sublayer is obtained through a representative core of the target sublayer in the target layer;

[0013] The fractal dimensions of the different temporary plugging mixed systems are obtained through a model of cumulative particle size and particle radius.

[0014] Preferably, the process of obtaining the fractal dimension of the pore structure of the target sublayer through the representative core of the target sublayer in the target layer is specifically as follows:

[0015] S11: Obtaining a capillary pressure curve representing the core;

[0016] S12: establishing a functional relationship between the capillary pressure and the saturation of the wetting phase or the non-wetting phase according to the capillary pressure curve;

[0017] S13: Obtain the pore structure fractal dimension of the target sub-layer according to the capillary pressure and the wetting phase or non-wetting phase saturation function relationship.

[0018] Preferably, the capillary pressure and the wetting phase or non-wetting phase saturation function relationship is:

[0019]

[0020] In the formula: S is the wetting phase / non-wetting phase saturation; r max is the maximum pore throat radius; r is the pore throat radius; D is the fractal dimension.

[0021] Preferably, the model relationship between the cumulative particle size and the particle size radius is:

[0022] φ = A(d min / d max ) 3-D

[0023] In the formula: A is a constant; d min is the minimum particle size of the temporary plugging agent in the system; d max is the maximum particle size of the temporary plugging agent in the system, and D is the fractal dimension.

[0024] Preferably, determine the far-field temporary plugging mixed system by the pore structure fractal dimension of the target layer and the fractal dimension of different temporary plugging mixed systems. Specifically:

[0025] When the absolute value of the deviation between the pore structure fractal dimension and the fractal dimension of the temporary plugging mixed system is not greater than 0.1, then this temporary plugging mixed system is the optimal temporary plugging mixed system;

[0026] Otherwise, compound the temporary plugging mixed system to determine the optimal temporary plugging mixed system.

[0027] When compounding the temporary plugging mixed system, it is carried out by the following formula:

[0028] yD 1 = x 1 D 2i + x 2 D 2j + C

[0029] In the formula: D 1 is the fractal dimension of the target mixed temporary plugging system; D 2i is the fractal dimension of the known or existing temporary plugging agent A; D 2j is the fractal dimension of the known or existing temporary plugging agent B; x 1 , x 2 , y are mixing ratio coefficients; C is a constant.

[0030] A far-field temporary plugging mixed system based on fractal characteristics is determined by the above method.

[0031] Application of the above far-field temporary plugging hybrid system based on fractal characteristics in far-field temporary plugging.

[0032] A far-field temporary plugging hybrid system determination system based on fractal characteristics, comprising:

[0033] Data acquisition unit: The data acquisition unit is used to acquire the fractal dimension of the pore structure of the target sub-layer and the fractal dimensions of different temporary plugging hybrid systems; the fractal dimension of the pore structure of the target sub-layer is obtained through the representative core of the target sub-layer within the target layer; the fractal dimensions of different temporary plugging hybrid systems are obtained through the model of cumulative grain size and grain radius;

[0034] Data processing unit: The data processing unit is used to determine the far-field temporary plugging hybrid system through the fractal dimension of the pore structure of the target layer and the fractal dimensions of different temporary plugging hybrid systems.

[0035] A terminal device, comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the steps of the above method are implemented when the processor executes the computer program.

[0036] A computer-readable storage medium storing a computer program, wherein the steps of the above method are implemented when the computer program is executed by a processor.

[0037] Compared with the prior art, the present invention has the following beneficial technical effects:

[0038] The present invention discloses a method for determining a far-field temporary plugging hybrid system based on fractal characteristics. The method determines the optimal temporary plugging system by comparing the fractal dimension of the pore structure of the target sub-layer with the fractal dimensions of different temporary plugging hybrid systems. Through the comparison of fractal dimensions, a variety of specifications of temporary plugging agents are compounded, and a certain amount of softening particles and elastic particles are added to the rigid bridging particles, which can further enhance the plugging effect, better apply the far-field temporary plugging technology, and more efficiently form a crack-end plugging and a crack-face mud cake for the far-field temporary plugging hybrid system. The soluble temporary plugging agent and the proppant are optimally matched, and the temporary plugging effect is not weakened due to the addition of the proppant. And it ensures that the temporary secondary fractures are reopened and maintained after the soluble substances are completely dissolved, thereby increasing the fracture network complexity for larger-area oil and gas flow. Description of the Drawings

[0039] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings required for use in the embodiments are briefly introduced below. It should be understood that the following drawings only show certain embodiments of the present invention and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other related drawings can be obtained based on these drawings without creative work.

[0040] Figure 1 It is a flow chart of a method for determining a far-field temporary plugging hybrid system based on fractal characteristics in the present invention;

[0041] Figure 2 It is a schematic diagram of the remote field temporary plugging system in the present invention for plugging cracks;

[0042] Figure 3 It is a structural schematic diagram of a far-field temporary plugging hybrid system determination system based on fractal characteristics in the present invention. DETAILED DESCRIPTION

[0043] In order to make the purpose, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Generally, the components of the embodiments of the present invention described and shown in the drawings here can be arranged and designed in various different configurations.

[0044] Therefore, the following detailed description of the embodiments of the present invention provided in the accompanying drawings is not intended to limit the scope of the invention claimed for protection, but merely represents selected embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0045] It should be noted that similar reference numerals and letters denote similar items in the following drawings, and therefore, once an item is defined in one drawing, further definition and explanation thereof is not required in subsequent drawings.

[0046] In the description of the embodiments of the present invention, it should be noted that if the terms "upper", "lower", "horizontal", "inner", etc. indicate an orientation or positional relationship based on the orientation or positional relationship shown in the drawings, or the orientation or positional relationship in which the product of the invention is usually placed when in use, it is only for the convenience of describing the present invention and simplifying the description, and does not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present invention. In addition, the terms "first", "second", etc. are only used to distinguish the description, and cannot be understood as indicating or implying relative importance.

[0047] In addition, if the term "horizontal" appears, it does not mean that the component must be absolutely horizontal, but can be slightly tilted. For example, "horizontal" only means that its direction is more horizontal than "vertical", which does not mean that the structure must be completely horizontal, but can be slightly tilted.

[0048] In the description of the embodiments of the present invention, it is also necessary to explain that, unless otherwise clearly specified and limited, the terms "set", "install", "connect", and "connect" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal connection of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0049] The present invention is further described in detail below in conjunction with the accompanying drawings:

[0050] Example 1

[0051] like Figure 1 As shown, the present invention discloses a method for determining a far-field temporary plugging hybrid system based on fractal characteristics, comprising the following steps:

[0052] S1: obtaining the fractal dimension of the pore structure of the target sublayer and the fractal dimensions of different temporary plugging mixed systems; the fractal dimension of the pore structure of the target sublayer is obtained through the representative core of the target sublayer in the target layer;

[0053] The fractal dimensions of the different temporary plugging mixed systems are obtained through a model of cumulative particle size and particle radius;

[0054] S2: Determine the far-field temporary plugging mixed system through the fractal dimension of the pore structure of the target layer and the fractal dimensions of different temporary plugging mixed systems.

[0055] In a preferred embodiment, the process of obtaining the fractal dimension of the pore structure of the target sublayer through the representative core of the target sublayer in the target layer is specifically as follows:

[0056] S11: performing a high-pressure mercury injection experiment on the core to obtain a capillary pressure curve of the core;

[0057] S12: establishing a functional relationship between the capillary pressure and the saturation of the wetting phase or the non-wetting phase according to the capillary pressure curve;

[0058] S13: Obtaining the pore structure fractal dimension of the target sublayer according to the functional relationship between the capillary pressure and the saturation of the wetting phase or the non-wetting phase.

[0059] If there are multiple cores, the average capillary pressure curve is calculated based on the capillary pressure curves of all cores obtained.

[0060] The representative core of the target sublayer is obtained specifically as follows: based on the seismic phase-sedimentary phase-diagenetic phase, the sublayer type in the target layer on the profile is divided, and the target sublayer type in the target layer is determined, and the representative core of the target sublayer is obtained according to the target sublayer type.

[0061] Specifically, in the present invention, the functional relationship between the capillary pressure and the saturation of the wetting phase or the non-wetting phase is:

[0062]

[0063] Where: S is the saturation of wetting phase / non-wetting phase, a dimensionless parameter;

[0064] r max is the maximum pore throat radius, mm;

[0065] r is the pore throat radius, mm;

[0066] D is the fractal dimension, a dimensionless parameter.

[0067] The model relationship between the cumulative particle size and the particle radius is:

[0068] φ=A(d min / d max ) 3-D

[0069] Where: A is a constant, dimensionless parameter;

[0070] d min is the minimum temporary plugging agent particle size in the system, mm;

[0071] d max is the maximum temporary plugging agent particle size in the system, mm;

[0072] D is the fractal dimension, a dimensionless parameter.

[0073] More specifically, the far-field temporary plugging mixed system is determined by the fractal dimension of the pore structure of the target layer and the fractal dimensions of different temporary plugging mixed systems, specifically:

[0074] When the absolute value of the deviation between the fractal dimension of the pore structure and the fractal dimension of the temporary plugging mixed system is no more than 0.1, the temporary plugging mixed system is the optimal temporary plugging mixed system;

[0075] Otherwise, the temporary plugging mixed system is compounded to determine the optimal temporary plugging mixed system.

[0076] When compounding the temporary plugging mixed system, it is carried out according to the following formula:

[0077] yD 1 =x 1D 2i +x 2 D 2j +C

[0078] Where: D 1 is the fractal dimension of the target mixed temporary plugging system, a dimensionless parameter;

[0079] D 2i is the fractal dimension of the known or existing temporary plugging agent A;

[0080] D 2j is the fractal dimension of the known or existing temporary plugging agent B;

[0081] x 1 , x 2 , y is the ratio coefficient, which is a constant;

[0082] C is a constant, dimensionless parameter.

[0083] Select multiple types of temporary plugging agents or systems for proportion compounding, and finally select a type of compound temporary plugging agent with lower price, more convenient transportation and more convenient acquisition. Here, the currently available temporary plugging granular materials are used to calculate the optimal compounding ratio during compounding, and a temporary plugging agent system close to the complexity of the rock body is obtained based on fractal theory, which can block the seepage seam end more quickly and efficiently.

[0084] At the same time, the present invention also discloses a far-field temporary plugging mixed system based on fractal characteristics determined based on the above method, which allows temporary plugging agents of various specifications to be compounded, and a certain amount of softening particles and elastic particles are added to the rigid bridging particles, which can further enhance the plugging effect, better utilize the far-field temporary plugging technology, and the far-field temporary plugging mixed system more efficiently forms seam end plugging and seam surface mud cake, and the soluble temporary plugging agent and the proppant are optimally matched, and the temporary plugging effect is not weakened by the addition of the proppant. And ensure that the temporary branch cracks are reopened, and maintain support after the soluble substance is completely dissolved, thereby increasing the complexity of the seam network to provide a larger area of ​​oil and gas flow. The existing temporary plugging steering fracturing uses temporary plugging steering materials with different size combinations to temporarily plug the seams, plugging the cracks of different sizes formed by the first fracturing, and there is a weak controllability, so that the crack extension pressure is not increased by a large amount, the crack steering extension is not obvious, and it is not easy to form a steering crack. Therefore, the far-field temporary plugging technology is adopted, and the far-field temporary plugging agent with finer particle size and diversified type combinations in the present invention is used to form the seam end plugging and the seam surface mud cake to improve the temporary plugging success rate. Far-field temporary plugging requires the cooperation of proppants, and the temporary plugging performance may weaken with the addition of proppants. Therefore, it is necessary to maximize the heterogeneity of the pore structure of the temporary plugging mixed system composed of temporary plugging agents and proppants based on fractal characteristics, achieve efficient temporary plugging, and open the fracture network.

[0085] At the same time, the present invention also discloses the application of the above-mentioned far-field temporary plugging hybrid system based on fractal characteristics in far-field temporary plugging, such as Figure 2 As shown in the figure, the plugging system has excellent plugging effect, making good use of the remote temporary plugging technology, forming the seam end plugging and seam surface mud cake more efficiently, and the soluble temporary plugging agent and proppant are optimally matched, and the temporary plugging effect is not weakened by the addition of proppant. It also ensures that the temporary branch fractures are reopened and maintain support after the soluble substances are completely dissolved, thereby increasing the complexity of the fracture network to provide a larger area for oil and gas flow.

[0086] Example 2

[0087] At the same time Figure 3 As shown, the present invention also discloses a far-field temporary plugging hybrid system determination system based on fractal characteristics, comprising:

[0088] Data acquisition unit: The data acquisition unit is used to obtain the fractal dimension of the pore structure of the target sublayer and the fractal dimensions of different temporary plugging mixed systems; the fractal dimension of the pore structure of the target sublayer is obtained through the representative core of the target sublayer in the target layer; the fractal dimension of the different temporary plugging mixed systems is obtained through the model of cumulative particle size and particle size radius;

[0089] Data processing unit: The data processing unit is used to determine the far-field temporary plugging mixed system through the fractal dimension of the pore structure of the target layer and the fractal dimensions of different temporary plugging mixed systems.

[0090] Example 3

[0091] In order to further illustrate the technical solution of the present invention, the following examples are used for explanation:

[0092] Composite temporary plugging and fracturing was carried out for a tight sandstone gas well. The target layer was He 8, with an effective reservoir of 3m (3893-3896m) and good gas content, which was interpreted as a gas layer. A method for efficient application of remote temporary plugging agents was used to perform the following steps:

[0093] Step 1) The Box 8 section of the study area has developed large delta front deposits, and the wells are located in the underwater distributary channel microfacies, in the middle of the sand body, the Box 8 is thicker, and the physical properties are better. The lithology is medium-fine-grained lithic quartz sandstone, and the pore types are mainly intergranular pores and dissolved pores, which meets the application scope of a method for efficient application of a remote temporary plugging agent;

[0094] Step 2) Obtain the target layer core for high-pressure mercury injection experiment to obtain the capillary pressure curve and its characteristic parameters, and use the fractal dimension calculation formula to obtain the fractal dimension D1 of the pore structure of the fracturing target layer, which is about 2.1756-2.8865, with an average of 2.5423.

[0095] Step 3) The mixed temporary plugging system A1, the mixed temporary plugging system A2, and the mixed temporary plugging system A3 were tested for cumulative particle size distribution in the laboratory, and the fractal dimension was calculated based on the particle size distribution. The results are shown in Table 1:

[0096] Table 1 Fractal dimensions of different mixed temporary plugging systems

[0097]

[0098]

[0099] Step 4) Compare the fractal dimension of the pore structure of the construction target layer with the fractal dimension of the mixed temporary plugging system A1. The error is less than 0.05. The mixed temporary plugging system A1 can be directly used as the far-field temporary plugging agent in the construction operation. The implementation effect is as follows: After the first fracturing construction, stop the pump, and the subsequent pump uses a viscosity of 3-4mPa·s and a displacement of 5-6m 3 / min base liquid carrying mixed temporary plugging system A1 entered, with a cumulative addition of 150kg. After the temporary plugging particles were added, the average pressure increased by 6.5Mpa, and the temporary plugging agent had an obvious plugging effect.

[0100] Example 4

[0101] A schematic diagram of a terminal device provided in an embodiment of the present invention. The terminal device of this embodiment includes: a processor, a memory, and a computer program stored in the memory and executable on the processor. When the processor executes the computer program, the steps in the above-mentioned method embodiments are implemented. Alternatively, when the processor executes the computer program, the functions of the modules / units in the above-mentioned device embodiments are implemented.

[0102] The computer program may be divided into one or more modules / units, and the one or more modules / units are stored in the memory and executed by the processor to accomplish the present invention.

[0103] The terminal device may be a computing device such as a desktop computer, a notebook, a PDA, a cloud server, etc. The terminal device may include, but is not limited to, a processor and a memory.

[0104] The processor can be a central processing unit (CPU), or other general-purpose processors, digital signal processors (DSP), application-specific integrated circuits (ASIC), field-programmable gate arrays (FPGA) or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, etc.

[0105] The memory may be used to store the computer program and / or module, and the processor implements various functions of the terminal device by running or executing the computer program and / or module stored in the memory and calling the data stored in the memory.

[0106] If the module / unit integrated in the terminal device is implemented in the form of a software functional unit and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on this understanding, the present invention implements all or part of the processes in the above-mentioned embodiment method, and can also be completed by instructing the relevant hardware through a computer program. The computer program can be stored in a computer-readable storage medium, and the computer program can implement the steps of the above-mentioned various method embodiments when executed by the processor. Among them, the computer program includes computer program code, and the computer program code can be in source code form, object code form, executable file or some intermediate form. The computer-readable medium may include: any entity or device capable of carrying the computer program code, recording medium, U disk, mobile hard disk, disk, optical disk, computer memory, read-only memory (ROM, Read-Only Memory), random access memory (RAM, Random Access Memory), electric carrier signal, telecommunication signal and software distribution medium. It should be noted that the content contained in the computer-readable medium can be appropriately increased or decreased according to the requirements of legislation and patent practice in the jurisdiction. For example, in some jurisdictions, according to legislation and patent practice, computer-readable media do not include electric carrier signals and telecommunication signals.

[0107] The above are only preferred embodiments of the present invention and are not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A method for determining a far - field temporary plugging hybrid system based on fractal features, characterized in that, it includes the following steps: S1: Obtain the pore structure fractal dimension of the target sub - layer and the fractal dimensions of different temporary plugging hybrid systems; S2: Determine the far - field temporary plugging hybrid system based on the pore structure fractal dimension of the target layer and the fractal dimensions of different temporary plugging hybrid systems; The pore structure fractal dimension of the target sub - layer is obtained through the representative core of the target sub - layer within the target layer; The fractal dimensions of different temporary plugging hybrid systems are obtained through a model of cumulative particle size and particle radius.

2. The method for determining a far - field temporary plugging hybrid system based on fractal features according to claim 1, characterized in that, the process of obtaining the pore structure fractal dimension of the target sub - layer through the representative core of the target sub - layer within the target layer is specifically as follows: S11: Obtain the capillary pressure curve of the representative core; S12: Establish a functional relationship between capillary pressure and wetting phase or non - wetting phase saturation according to the capillary pressure curve; S13: Obtain the pore structure fractal dimension of the target sub - layer according to the functional relationship between capillary pressure and wetting phase or non - wetting phase saturation.

3. The method for determining a far - field temporary plugging hybrid system based on fractal features according to claim 2, characterized in that, the functional relationship between capillary pressure and wetting phase or non - wetting phase saturation is: Where: S is the saturation of wetting phase / non-wetting phase; r max is the maximum pore throat radius; r is the pore throat radius; D is the fractal dimension.

4. The method for determining a far - field temporary plugging hybrid system based on fractal features according to claim 1, characterized in that, the model relationship between cumulative particle size and particle radius is: φ=A(d min / d max ) 3-D Where: A is a constant; d min is the minimum temporary plugging agent particle size in the system; d max is the maximum temporary plugging agent particle size in the system, and D is the fractal dimension.

5. The method for determining a far - field temporary plugging hybrid system based on fractal features according to claim 1, characterized in that, determining the far - field temporary plugging hybrid system based on the pore structure fractal dimension of the target layer and the fractal dimensions of different temporary plugging hybrid systems is specifically as follows: When the absolute value of the deviation between the pore structure fractal dimension and the fractal dimension of the temporary plugging hybrid system is not greater than 0.1, then this temporary plugging hybrid system is the optimal temporary plugging hybrid system; Otherwise, compound the temporary plugging hybrid system to determine the optimal temporary plugging hybrid system; When compounding the temporary plugging hybrid system, it is carried out through the following formula: yD 1 =x 1 D 2i +x 2 D 2j +C Where: D 1 is the fractal dimension of the target mixed temporary plugging system; D 2i is the fractal dimension of the known or existing temporary plugging agent A; D 2j is the fractal dimension of the known or existing temporary plugging agent B; x 1 , x 2 , y is the matching coefficient; C is a constant.

6. A far - field temporary plugging hybrid system based on fractal features, characterized in that, it is determined by the method described in any one of claims 1 - 5.

7. Application of the far - field temporary plugging hybrid system based on fractal features described in claim 6 in far - field temporary plugging.

8. A system for determining a far - field temporary plugging hybrid system based on fractal features, characterized in that, it includes: Data acquisition unit: The data acquisition unit is used to obtain the pore structure fractal dimension of the target sub - layer and the fractal dimensions of different temporary plugging hybrid systems; The pore structure fractal dimension of the target sub - layer is obtained through the representative core of the target sub - layer within the target layer; the fractal dimensions of different temporary plugging hybrid systems are obtained through a model of cumulative particle size and particle radius; Data processing unit: The data processing unit is used to determine the far - field temporary plugging hybrid system based on the pore structure fractal dimension of the target layer and the fractal dimensions of different temporary plugging hybrid systems.

9. A terminal device, including a memory, a processor, and a computer program stored in the memory and executable on the processor, It is characterized in that When the processor executes the computer program, the steps of the method according to any one of claims 1 to 5 are implemented.

10. A computer-readable storage medium storing a computer program. It is characterized in that When the computer program is executed by a processor, the steps of the method according to any one of claims 1 to 5 are implemented.

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