Single-section multi-cluster fracturing method for ultra-deep shale gas, electronic equipment and medium

Abstract

The invention discloses a single-section multi-cluster fracturing method for ultra-deep shale gas, electronic equipment and a medium. The method comprises the following steps: calculating formation fracture pressure of a horizontal section, and further calculating inter-cluster interference stress; determining the position of a perforation cluster; calculating the added value of the flowing bottomhole pressure, and controlling the flowing bottomhole pressure; according to the perforation cluster grouping condition, in-crack temporary plugging design and inter-crack temporary plugging design are carried out on each group of perforation clusters in the fracturing section; and the steps are repeated, and transformation of all the fractured sections of the horizontal well is completed. According to the method, the positions of the perforation clusters are determined in a differentiated mode, multi-cluster cracks are initiated in batches, and the temporary plugging method is adopted, so that the fracturing transformation volume of the ultra-deep shale gas is increased, meanwhile, the fracturing transformation cost is reduced, and the ultra-deep shale gas is assisted to achieve benefit development.

Description

Technical Field

[0001] The present invention relates to the technical field of oil and gas reservoir development research, and more specifically, to a single-stage multi-cluster fracturing method, electronic equipment and medium for ultra-deep shale gas. Background Art

[0002] In recent years, both at home and abroad, active exploration has been carried out in deep shale gas drilling, completion and fracturing engineering technologies, and important progress has been made, which has promoted exploration breakthroughs and reserve utilization in some regions. For example, in the Haynesville, Eagle Ford, and Canna Woodford blocks in North America, the ultra-dense cutting volume fracturing technology is used for shallow and deep shale gas with a vertical depth of 4,100 m, and the average single-well EUR has reached 1.01×108~1.47×108m 3 , with a single well cost of US$12 million, and commercial development has been achieved; the post-pressure test production of domestic Dongye Shen 2 Well and Dingye 7 Well has exceeded 40×104m 3 , and achieved good development benefits. However, for ultra-deep shale gas with a vertical depth of >4500m, no breakthrough has been made in the volume fracturing technology at home and abroad.

[0003] The main factors limiting the effect of ultra-deep shale gas fracturing include: (1) the difficulty in forming a complex fracture network and the small transformation volume. Ultra-deep shale gas reservoirs are buried deep (>4500m) and have high formation fracture pressure. Under the same well depth structure and horizontal section length conditions, ultra-deep shale gas horizontal well fracturing requires higher construction pressure. Currently, 140MPa fracturing equipment usually cannot meet the construction requirements of large displacement (16-20m3 / min) of ultra-deep shale gas; ultra-deep shale reservoirs often have strong tectonic effects and high horizontal biaxial stress differences. For example, the horizontal biaxial stress difference of ultra-deep shale gas in southeastern Sichuan, my country can reach 20MPa. Under high horizontal biaxial stress difference conditions, a higher net pressure is required to form a complex fracture network, which cannot be met by current fracturing equipment; in addition, ultra-deep shale gas reservoirs often have high temperature and high pressure formation conditions and strong rock plasticity. The above limiting conditions make the fractures formed by ultra-deep shale gas fracturing low in complexity, small in transformation volume, and generally low in production after fracturing. (2) High well construction and transformation costs. With the increase of vertical depth, the drilling cost increases significantly; due to the high pressure and small displacement of fracturing transformation, the fracturing cost increases. In order to enhance the transformation effect, ultra-deep shale gas often adopts a single-stage and few-cluster fracturing mode (single-stage <3 clusters), which will inevitably increase the number of transformation stages in a single well, thereby further increasing the fracturing transformation cost.

[0004] Therefore, to achieve the efficient development of ultra-deep shale gas, breakthroughs are needed in both creating complex fractures and reducing costs. Based on the experience of developing medium and shallow shale gas, single-stage multi-cluster fracturing can effectively reduce the transformation cost. In addition, by increasing the number of transformation clusters and increasing the control area of ​​the transformation fracture, the simple fracture morphology can be compensated to a certain extent. However, there are many problems in the use of single-stage multi-cluster fracturing mode in ultra-deep shale gas reservoirs: (1) Inter-stage interference causes the multi-cluster fractures to be unable to fracture evenly. Due to the high fracture pressure of ultra-deep shale, once the dominant cluster fractures, it will be difficult for other clusters to fracture or their expansion will be restricted. (2) Single-stage multi-cluster is not conducive to sand addition. Under multi-cluster conditions, the liquid inflow of a single cluster is reduced, the fracture width becomes narrower, and the difficulty of sand addition increases, which is not conducive to improving the long-term conductivity of the fracture. Under the above restrictions, ultra-deep shale gas fracturing transformation often adopts a single-stage few-cluster fracturing mode.

[0005] Therefore, it is necessary to develop a single-stage multi-cluster fracturing method, electronic equipment and medium for ultra-deep shale gas.

[0006] The information disclosed in the background technology section of the present invention is only intended to deepen the understanding of the general background technology of the present invention, and should not be regarded as acknowledging or suggesting in any form that the information constitutes the prior art already known to those skilled in the art. Summary of the invention

[0007] The present invention proposes a single-stage multi-cluster fracturing method, electronic equipment and medium for ultra-deep shale gas, which can increase the ultra-deep shale gas fracturing transformation volume by differentially determining the perforation cluster positions, initiating multi-cluster fractures in batches and temporary plugging methods, while reducing the fracturing transformation costs, thereby helping to achieve efficient development of ultra-deep shale gas.

[0008] In a first aspect, the present disclosure provides a single-stage multi-cluster fracturing method for ultra-deep shale gas, comprising:

[0009] Calculate the horizontal section formation fracture pressure, and then calculate the inter-cluster interference stress;

[0010] Determine the perforation cluster locations;

[0011] Calculate the increase of bottom hole flow pressure and control the bottom hole flow pressure;

[0012] According to the grouping of perforation clusters, temporary plugging design within the fractures and between the fractures is performed for each perforation cluster in the fracturing stage;

[0013] Repeat the above steps to complete the transformation of all fracturing stages of the horizontal well.

[0014] Preferably, determining the perforation cluster positions comprises:

[0015] The perforation cluster positions are selected according to the horizontal wellbore formation fracture pressure profile, with 1 to 2 clusters as a group and 3 to 4 perforation clusters in each section;

[0016] The distance between clusters is adjusted according to the inter-cluster interference stress, so that the difference between the sum of the fracturing pressure and the inter-cluster interference stress of each group of perforation clusters is less than a set threshold, and the difference between the sum of the fracturing pressure and the inter-cluster interference stress of different groups of perforation clusters is greater than the set threshold.

[0017] Preferably, the set threshold is 3 MPa.

[0018] Preferably, the bottom hole flow pressure increase is:

[0019] △P 流压 =△P 井口 -△P 井筒 -△P 孔眼 -△P 缝内

[0020] Among them, △P 井筒 Indicates the change in wellbore friction, P 井筒 =1.385×10 6 *d 4.8 *L*Q 1.8 *α, d, L, Q and α are wellbore diameter, wellbore length, construction displacement and fracturing fluid resistance reduction rate, △P 孔眼 Indicates the change in hole friction, P 孔眼 =a2*Q 2 , a2 is a fixed constant, △P 缝内 Indicates the change in flow resistance in the slit, P 缝内 =a3*β*Q 2 , a3 is a fixed constant, and β is the filtration loss correlation coefficient.

[0021] Preferably, the temporary plugging design in the seam includes:

[0022] According to the grouping of perforation clusters, the pumping program was designed for the first group of perforation clusters, and the temporary plugging design in the fracture was realized by adjusting the sand ratio and liquid viscosity.

[0023] Preferably, the diameter of the temporary plugging ball is 1.5 times the diameter of the perforation hole.

[0024] Preferably, the temporary plugging design between seams includes:

[0025] The number of temporary plugging balls between seams is determined according to the number of perforation holes in the first perforation cluster to achieve temporary plugging design between seams.

[0026] Preferably, the last group of perforation clusters in the fracturing stage does not require a temporary plugging design within the fractures or a temporary plugging design between the fractures.

[0027] In a second aspect, an embodiment of the present disclosure further provides an electronic device, the electronic device comprising:

[0028] A memory storing executable instructions;

[0029] A processor runs the executable instructions in the memory to implement the single-stage multi-cluster fracturing method for ultra-deep shale gas.

[0030] In a third aspect, an embodiment of the present disclosure further provides a computer-readable storage medium storing a computer program, which, when executed by a processor, implements the single-stage multi-cluster fracturing method for ultra-deep shale gas.

[0031] The methods and apparatus of the present invention have other features and advantages that will be apparent from, or will be described in detail in, the accompanying drawings and subsequent detailed descriptions incorporated herein, which together serve to explain the specific principles of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] The above and other objects, features and advantages of the present invention will become more apparent through a more detailed description of exemplary embodiments of the present invention in conjunction with the accompanying drawings, wherein like reference numerals generally represent like components throughout the exemplary embodiments of the present invention.

[0033] Figure 1 A flow chart showing the steps of a single-stage multi-cluster fracturing method for ultra-deep shale gas according to an embodiment of the present invention. DETAILED DESCRIPTION

[0034] The preferred embodiments of the present invention will be described in more detail below. Although the preferred embodiments of the present invention are described below, it should be understood that the present invention can be implemented in various forms and should not be limited to the embodiments set forth herein.

[0035] The present invention provides a single-stage multi-cluster fracturing method for ultra-deep shale gas, comprising:

[0036] Calculate the horizontal section formation fracture pressure, and then calculate the inter-cluster interference stress;

[0037] Determine the perforation cluster locations;

[0038] Calculate the increase of bottom hole flow pressure and control the bottom hole flow pressure;

[0039] According to the grouping of perforation clusters, temporary plugging design within the fractures and between the fractures is performed for each perforation cluster in the fracturing stage;

[0040] Repeat the above steps to complete the transformation of all fracturing stages of the horizontal well.

[0041] In one example, determining perforation cluster locations includes:

[0042] The perforation cluster positions are selected according to the horizontal wellbore formation fracture pressure profile, with 1 to 2 clusters as a group and 3 to 4 perforation clusters in each section;

[0043] The distance between clusters is adjusted according to the inter-cluster interference stress, so that the difference between the sum of the fracturing pressure and the inter-cluster interference stress of each group of perforation clusters is less than the set threshold, and the difference between the sum of the fracturing pressure and the inter-cluster interference stress of different groups of perforation clusters is greater than the set threshold.

[0044] In one example, the threshold is set to 3 MPa.

[0045] In one example, the bottom hole pressure increase is:

[0046] △P 流压 =△P 井口 -△P 井筒 -△P 孔眼 -△P 缝内

[0047] Among them, △P 井筒 Indicates the change in wellbore friction, P 井筒 =1.385×10 6 *d 4.8 *L*Q 1.8 *α, d, L, Q and α are wellbore diameter, wellbore length, construction displacement and fracturing fluid resistance reduction rate, △P 孔眼 Indicates the change in hole friction, P 孔眼 =a2*Q 2 , a2 is a fixed constant, △P 缝内 Indicates the change in flow resistance in the slit, P 缝内 =a3*β*Q 2 , a3 is a fixed constant, and β is the filtration loss correlation coefficient.

[0048] In one example, the temporary plugging design includes:

[0049] According to the grouping of perforation clusters, the pumping program was designed for the first group of perforation clusters, and the temporary plugging design in the fracture was realized by adjusting the sand ratio and liquid viscosity.

[0050] In one example, the diameter of the temporary plugging ball is 1.5 times the diameter of the perforation hole.

[0051] In one example, the inter-slit temporary plugging design includes:

[0052] The number of temporary plugging balls between seams is determined according to the number of perforation holes in the first perforation cluster to achieve temporary plugging design between seams.

[0053] In one example, the last set of perforation clusters in the fracturing stage does not require a temporary plugging design within the fractures or a temporary plugging design between the fractures.

[0054] Specifically, the present invention uses differentiated perforation cluster division, makes full use of the interference stress between clusters, and coordinates construction parameters such as displacement and fracturing fluid viscosity to accurately control the slow step-by-step rise of bottom hole flow pressure, thereby achieving batch-by-batch fracturing and filling of multiple clusters of fractures, and then achieves balanced transformation of all clusters through temporary plugging and other measures. The core of the present invention lies in the method for selecting the perforation cluster position, the method for controlling the bottom hole flow pressure, and the method for achieving efficient temporary plugging.

[0055] (1) Differentiated determination of perforation cluster positions: Usually, deep / ultra-deep shale gas fracturing reconstruction uses 2 to 4 clusters in a single stage. During the fracture creation stage, 2 to 4 clusters of fractures are all initiated by means of glue (or ultra-high viscosity slippery water) and rapid displacement. In the method of the present invention, there are 6 to 8 clusters in a single stage. Through the selection of sweet spot positions and the interference between clusters, 1 to 3 clusters of fractures are grouped together, so that the same group of clusters has similar initiation pressures (<0 to 3 MPa), while different groups have significantly different fracture initiation pressures (>3 MPa).

[0056] (2) Fracture initiation and fracture filling in batches: The key to achieving fracture initiation of multiple clusters of fractures in batches is to accurately control the bottomhole flow pressure and increase it slowly from small to large in steps. If the bottomhole flow pressure rises too quickly, multiple groups of perforation clusters will be fractured at the same time, resulting in many holes with liquid inlet at the same time, poor energy collection effect, and difficulty in adding sand. At the same time, if the bottomhole flow pressure increases gradually and slowly, even the perforation clusters in the same group will have a competitive fracture initiation relationship. Once a perforation cluster fractures first, it will inhibit the fracture of other perforation clusters in the same group, and the effect of simultaneously fractured a group of perforation clusters cannot be achieved. First, by pumping glue, the displacement is increased in steps and slowly, so that the bottomhole flow pressure exceeds the fracture initiation pressure of all clusters in the first group. After the fracture of the first group of fractures is initiated, it inhibits the fracture of other clusters. Therefore, the bottomhole flow pressure can be controlled to increase by another 2-3 MPa without causing fractures in other clusters. With the goal of single-group transformation, the pumping program is designed to complete the sand addition. After that, the near-well fracture channels are blocked by high-concentration temporary plugging agents, and the channels of the fluid inlet holes of the opened perforation clusters are blocked by temporary plugging balls. It is calculated that 50% to 75% of the fluid inlet channels are blocked, so as to control the generation of 3 to 5 MPa excitation pressure in the wellbore at the moment of temporary plugging ball plugging, and initiate the next group of fractures. 6 to 8 clusters of fracturing are completed according to the above method.

[0057] The specific implementation steps of this method are as follows:

[0058] 1) Calculate the horizontal formation fracture pressure

[0059] Based on the logging, mud recording and rock mechanics experimental data, the formation fracture pressure profile of the horizontal wellbore section is calculated.

[0060] 2) Calculate inter-cluster interference stress

[0061] According to the reservoir rock characteristics and construction conditions, the inter-cluster interference stress at different cluster spacings is calculated.

[0062] 3) Select perforation cluster location

[0063] According to the horizontal wellbore formation fracture pressure profile, the perforation cluster position is selected, with 1 to 2 clusters as a group. The fracture pressure of the perforation cluster position in the same group is similar. Each section is divided into 3 to 4 groups of perforation clusters. Then, the spacing between clusters is adjusted according to the interference stress between clusters, so that the fracture pressure of each group of perforation clusters and the sum of the interference stress between clusters are as close as possible (<3MPa), and the fracture pressure and the sum of the interference stress between clusters of different groups are significantly different (>3MPa).

[0064] 4) Calculate bottom hole flow pressure

[0065] The increase in wellhead pressure during fracturing is:

[0066] △P 井口 =△P 井筒 +△P 孔眼 +△P 缝内 +△P 流压

[0067] Among them, △P 井筒 Indicates the change in wellbore friction, P 井筒 =1.385×10 6 *d 4.8 *L*Q 1.8 *α, d, L, Q and α are wellbore diameter, wellbore length, construction displacement and fracturing fluid drag reduction rate, respectively. For fixed perforation clusters, d and L are constants, so P 井筒 =a1*Q 1.8 *α, a1 are fixed constants; △P 孔眼 Indicates the change in friction resistance of the hole. Similarly, P 孔眼 =a2*Q 2 , a2 is a fixed constant; △P 缝内 Indicates the change in flow resistance in the slit, P 缝内 =a3*β*Q 2 , a3 is a fixed constant, β is the filtration loss correlation coefficient; △P 流压 It is the increase value of bottom hole flowing pressure.

[0068] 5) Bottom hole pressure control strategy

[0069] According to the bottom hole pressure calculation formula in step 4), α and β are related to the properties of the fracturing fluid. Therefore, the bottom hole pressure can be accurately controlled by controlling the displacement and fluid properties, so that the single step increase of the bottom hole pressure is controlled within 3 MPa.

[0070] 6) Design the pumping procedure

[0071] According to the grouping of perforation clusters, the pumping program is designed for the first group of perforation clusters to meet the requirements of displacement, liquid volume and sand addition.

[0072] 7) Temporary plugging in the designed seam

[0073] In the later stage of the first group of perforation cluster transformation, the sand ratio and liquid viscosity were adjusted to achieve end sand removal, and a high-concentration temporary plugging agent was used at the tail to increase the flow resistance in the fracturing fluid fracture.

[0074] 8) Temporary plugging of design gaps

[0075] The number of temporary plugging balls between seams is determined according to the number of perforation holes in the first group of perforation clusters. The diameter of the temporary plugging balls is 1.5 times the diameter of the perforation holes. The plugging efficiency of the temporary plugging balls is calculated as 75%, and 50% to 75% of the holes in the first group of perforation clusters are controlled to be plugged. The specific number of plugged holes is determined according to the temporary plugging efficiency in the seams in step 7). If the flow resistance in the seams increases significantly after temporary plugging by the temporary plugging agent in step 7), the number of temporary plugging balls in step 8) is appropriately reduced.

[0076] 9) Use microseismic monitoring to monitor crack expansion.

[0077] 10) Repeat steps 4) to 9) to complete the fracturing and sanding of the remaining perforation clusters. Since the fracturing of this section will be completed after the last perforation cluster is completed, temporary plugging of the seams and inter-slits is not required during the pumping of the last perforation cluster.

[0078] 11) Repeat steps 1) to 10) to complete the reconstruction of all fracturing stages of the horizontal well.

[0079] 12) Use the production dissection technology to test the gas production effect after compression.

[0080] The present invention also provides an electronic device, which includes: a memory storing executable instructions; and a processor running the executable instructions in the memory to implement the above-mentioned single-stage multi-cluster fracturing method for ultra-deep shale gas.

[0081] The present invention also provides a computer-readable storage medium storing a computer program, which, when executed by a processor, implements the above-mentioned single-stage multi-cluster fracturing method for ultra-deep shale gas.

[0082] To facilitate understanding of the solutions and effects of the embodiments of the present invention, three specific application examples are given below. Those skilled in the art should understand that the examples are only for facilitating understanding of the present invention, and any specific details thereof are not intended to limit the present invention in any way.

[0083] Example 1

[0084] Figure 1A flow chart showing the steps of a single-stage multi-cluster fracturing method for ultra-deep shale gas according to an embodiment of the present invention.

[0085] like Figure 1 As shown, the single-stage multi-cluster fracturing method for ultra-deep shale gas includes: step 101, calculating the horizontal section formation fracture pressure, and then calculating the inter-cluster interference stress; step 102, determining the perforation cluster position; step 103, calculating the bottom hole flow pressure increase value, and controlling the bottom hole flow pressure; step 104, according to the perforation cluster grouping situation, performing intra-fracture temporary plugging design and inter-fracture temporary plugging design for each group of perforation clusters in the fracturing section; step 105, repeating the above steps to complete the transformation of all fracturing sections of the horizontal well.

[0086] A certain ultra-deep shale gas horizontal well X has a vertical depth of 4800m, a thickness of 30m, a Young's modulus of 40GPa, a Poisson's ratio of 0.2, a two-way horizontal stress difference of 20MPa, and a horizontal section length of 1500m. The ultra-deep shale gas single-stage multi-cluster fracturing method provided by this patent is used for volume fracturing transformation. The specific implementation steps are as follows:

[0087] 1) According to the logging interpretation data and core mechanics data, the horizontal section formation fracture pressure is calculated to be 121-129 MPa, and the difference in the horizontal section formation fracture pressure is relatively large.

[0088] 2) According to the brittle characteristics of the formation, it is calculated that when the cluster spacing is 6 to 15 m and the crack width (fracture opening) is 1 cm, the inter-cluster interference stress is 6.2 to 0.6 MPa.

[0089] 3) According to the formation differences in the horizontal section and the perforation cluster selection method of the present invention, the first fracturing section is divided into 6 clusters, each 2 clusters form a group, the average cluster spacing is 9.6m, the section length is 70m, and a single cluster has 6 holes with a hole diameter of 12mm.

[0090] 4) According to the calculation of bottom hole flow pressure, the fracturing fluid resistance reducing agent concentration is 0.8% and the displacement is 6.5m 3 / min, the bottom hole pressure is 124MPa, the first group of perforation clusters can all be fractured, and the displacement is increased to 8m after the fracture is initiated. 3 / min.

[0091] 5) Design the pumping procedure according to 2 clusters, with a single cluster liquid volume of 1000m 3 , sand volume 50m 3 .

[0092] 6) In the later stage of the first perforation cluster fracturing, 30 / 50 mesh proppant and 20% sand ratio were used for end desanding, and then 200 kg of temporary plugging agent was quickly injected.

[0093] 7) According to the change of bottom hole flow pressure, 15 18mm temporary plugging balls are placed.

[0094] 8) Repeat steps 4) to 7) to complete the fracturing of the second and third perforation clusters in the first section.

[0095] 9) Repeat steps 2) to 8) to complete the fracturing of the 2nd to 20th sections of the entire well.

[0096] 10) Microseismic monitoring and production profile testing show that multiple clusters of fractures have balanced initiation and expansion, and the gas production contribution rate of each cluster is relatively balanced.

[0097] Example 2

[0098] The present disclosure provides an electronic device, which includes: a memory storing executable instructions; a processor running the executable instructions in the memory to implement the above-mentioned single-stage multi-cluster fracturing method for ultra-deep shale gas.

[0099] An electronic device according to an embodiment of the present disclosure includes a memory and a processor.

[0100] The memory is used to store non-temporary computer-readable instructions. Specifically, the memory may include one or more computer program products, which may include various forms of computer-readable storage media, such as volatile memory and / or non-volatile memory. The volatile memory may, for example, include random access memory (RAM) and / or cache memory (cache), etc. The non-volatile memory may, for example, include read-only memory (ROM), hard disk, flash memory, etc.

[0101] The processor may be a central processing unit (CPU) or other forms of processing units having data processing capabilities and / or instruction execution capabilities, and may control other components in the electronic device to perform desired functions. In one embodiment of the present disclosure, the processor is used to run the computer-readable instructions stored in the memory.

[0102] Those skilled in the art should be able to understand that in order to solve the technical problem of how to obtain a good user experience, the present embodiment may also include well-known structures such as a communication bus and an interface, and these well-known structures should also be included in the protection scope of the present disclosure.

[0103] For detailed description of this embodiment, reference may be made to the corresponding descriptions in the aforementioned embodiments, which will not be repeated here.

[0104] Example 3

[0105] An embodiment of the present disclosure provides a computer-readable storage medium storing a computer program. When the computer program is executed by a processor, the single-stage multi-cluster fracturing method for ultra-deep shale gas is implemented.

[0106] According to the computer-readable storage medium of the embodiment of the present disclosure, non-transitory computer-readable instructions are stored thereon. When the non-transitory computer-readable instructions are executed by a processor, all or part of the steps of the above-mentioned methods of each embodiment of the present disclosure are executed.

[0107] The above-mentioned computer-readable storage media include, but are not limited to: optical storage media (e.g., CD-ROM and DVD), magneto-optical storage media (e.g., MO), magnetic storage media (e.g., magnetic tape or mobile hard disk), media with built-in rewritable non-volatile memory (e.g., memory card) and media with built-in ROM (e.g., ROM box).

[0108] Those skilled in the art should understand that the purpose of the above description of the embodiments of the present invention is only to exemplarily illustrate the beneficial effects of the embodiments of the present invention, and is not intended to limit the embodiments of the present invention to any given examples.

[0109] The embodiments of the present invention have been described above, and the above description is exemplary, not exhaustive, and is not limited to the disclosed embodiments. Many modifications and changes will be apparent to those skilled in the art without departing from the scope and spirit of the described embodiments.

Claims

1. A single-stage multi-cluster fracturing method for ultra-deep shale gas, characterized in that: include: Calculate the horizontal section formation fracture pressure, and then calculate the inter-cluster interference stress; Determine the perforation cluster locations; Calculate the increase of bottom hole flow pressure and control the bottom hole flow pressure; According to the grouping of perforation clusters, temporary plugging design within the fractures and between the fractures is performed for each perforation cluster in the fracturing stage; Repeat the above steps to complete the transformation of all fracturing stages of the horizontal well.

2. The single-stage multi-cluster fracturing method for ultra-deep shale gas according to claim 1, wherein: Determining the location of perforation clusters includes: The perforation cluster positions are selected according to the horizontal wellbore formation fracture pressure profile, with 1 to 2 clusters as a group and 3 to 4 perforation clusters in each section; The distance between clusters is adjusted according to the inter-cluster interference stress, so that the difference between the sum of the fracturing pressure and the inter-cluster interference stress of each group of perforation clusters is less than a set threshold, and the difference between the sum of the fracturing pressure and the inter-cluster interference stress of different groups of perforation clusters is greater than the set threshold.

3. The single-stage multi-cluster fracturing method for ultra-deep shale gas according to claim 1, wherein: The set threshold is 3 MPa.

4. The single-stage multi-cluster fracturing method for ultra-deep shale gas according to claim 1, wherein: The increase in bottom hole flow pressure is: △P 流压 =△P 井口 -△P 井筒 -△P 孔眼 -△P 缝内 Among them, △P 井筒 Indicates the change in wellbore friction, P 井筒 =1.385×10 6 *d 4.8 *L*Q 1.8 *α, d, L, Q and α are wellbore diameter, wellbore length, construction displacement and fracturing fluid resistance reduction rate, △P 孔眼 Indicates the change in hole friction, P 孔眼 =a2*Q 2 , a2 is a fixed constant, △P 缝内 Indicates the change in flow resistance in the slit, P 缝内 =a3*β*Q 2 , a3 is a fixed constant, and β is the filtration loss correlation coefficient.

5. The single-stage multi-cluster fracturing method for ultra-deep shale gas according to claim 1, wherein: The temporary plugging design in the seam includes: According to the grouping of perforation clusters, the pumping program was designed for the first group of perforation clusters, and the temporary plugging design in the fracture was realized by adjusting the sand ratio and liquid viscosity.

6. The single-stage multi-cluster fracturing method for ultra-deep shale gas according to claim 5, wherein: The diameter of the temporary plugging ball is 1.5 times the diameter of the perforation hole.

7. The single-stage multi-cluster fracturing method for ultra-deep shale gas according to claim 1, wherein: The temporary plugging design between seams includes: The number of temporary plugging balls between seams is determined according to the number of perforation holes in the first perforation cluster to achieve temporary plugging design between seams.

8. The single-stage multi-cluster fracturing method for ultra-deep shale gas according to claim 1, wherein: The last group of perforation clusters in the fracturing stage does not require a temporary plugging design within the fracture or between the fractures.

9. An electronic device, characterized in that: The electronic device comprises: A memory storing executable instructions; A processor, wherein the processor runs the executable instructions in the memory to implement the single-stage multi-cluster fracturing method for ultra-deep shale gas according to any one of claims 1-8.

10. A computer-readable storage medium, characterized in that: The computer-readable storage medium stores a computer program, which, when executed by a processor, implements the single-stage multi-cluster fracturing method for ultra-deep shale gas according to any one of claims 1 to 8.

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