Fracture morphology interpretation method of three-dimensional well network based on distributed optical fiber monitoring

Abstract

The present application provides a method for interpreting fracture morphology of a three-dimensional well network based on distributed optical fiber monitoring. It includes: obtaining geological parameters, fracturing well construction parameters, adjacent monitoring well parameters, and actual optical fiber strain rate; the three-dimensional well network includes multiple horizontal fracturing wells, and the optical fiber monitoring wells are used to monitor the crack expansion in the horizontal fracturing wells. The actual optical fiber strain rate represents the rate at which the actually measured optical fiber strain changes over time when subjected to external stress; according to the geological parameters, the fracturing well construction parameters, and the adjacent monitoring well parameters, simulated fracture morphology information is obtained; according to the simulated fracture morphology information, geological parameters, and adjacent monitoring well parameters, simulated optical fiber strain rate is obtained; according to the simulated optical fiber strain rate and the actual optical fiber strain rate, it is determined whether the simulated fracture morphology information is the actual fracture morphology information of the horizontal fracturing well. By comparing the optical fiber strain rate, the fracture morphology can be monitored in real time.

Description

Technical Field

[0001] The present application relates to the field of numerical simulation technology, and in particular to a method for interpreting fracture morphology of a three-dimensional well network based on distributed optical fiber monitoring. Background Art

[0002] Shale oil and gas resources have great potential for exploration and development and are an important strategic successor resource for oil development. In order to maximize the volume of reservoir transformation and improve the recovery of oil and gas resources, multi-layer three-dimensional well network hydraulic fracturing technology has been widely used. However, during the three-dimensional well network fracturing process, well interference or crosstalk occurs frequently, which seriously affects the overall utilization of the reservoir and the development benefits of the well group.

[0003] Therefore, it is an urgent problem to carry out real-time crack morphology monitoring during the fracturing process to guide the timely adjustment of fracturing construction parameters. Summary of the invention

[0004] The present application provides a method for interpreting fracture morphology of three-dimensional well network fracturing based on distributed optical fiber monitoring, which is used to solve the problem of real-time fracture morphology monitoring.

[0005] In a first aspect, the present application provides a method for interpreting fracture morphology of a three-dimensional well network based on distributed optical fiber monitoring, comprising:

[0006] Obtaining geological parameters, fracturing well construction parameters, adjacent monitoring well parameters, and actual optical fiber strain rate; wherein the geological parameters represent geological characteristics and geological conditions; the fracturing well construction parameters represent the construction requirements for fracturing horizontal fracturing wells; the adjacent monitoring well parameters represent the well parameters of the optical fiber monitoring wells in a preset area outside the three-dimensional well network, the three-dimensional well network includes multiple horizontal fracturing wells, and the optical fiber monitoring wells are used to monitor the expansion of fracturing cracks in the horizontal fracturing wells; the actual optical fiber strain rate represents the rate at which the actually measured optical fiber length changes over time when subjected to external stress;

[0007] According to geological parameters, fracturing well construction parameters, and adjacent monitoring well parameters, simulated fracture morphology information is obtained; wherein the simulated fracture morphology information includes at least one of simulated fracture width, fracture length, and fluid pressure in the fracture;

[0008] The simulated optical fiber strain rate is obtained according to the simulated fracture morphology information, geological parameters and adjacent monitoring well parameters; wherein the simulated optical fiber strain rate represents the rate at which the simulated optical fiber length changes with time at different time periods;

[0009] According to the simulated optical fiber strain rate and the actual optical fiber strain rate, it is determined whether the simulated fracture morphology information is the actual fracture morphology information of the horizontal fracturing well; wherein the actual fracture morphology information includes at least one of the actual fracture width, fracture length, and fluid pressure in the fracture.

[0010] Among them, in this application, according to geological parameters, fracturing well construction parameters, and adjacent monitoring well parameters, simulated fracture morphology information is obtained, including:

[0011] Determine the initial time period length according to the preset initial crack length; wherein the time period length represents the injection of liquid into the horizontal fracturing well within the range of the time period length;

[0012] Determine the crack width, crack length, and fluid pressure in the crack corresponding to the next time period length according to the initial time period length, the preset initial crack width, and the fracturing well construction parameters, and continue to determine the new next time period length according to the crack length corresponding to the next time period length;

[0013] Until the total volume of liquid injected in all the determined time periods reaches the preset volume, the crack width, crack length, and fluid pressure in the crack corresponding to the last time period are obtained, which is the simulated crack morphology information.

[0014] Among them, in this application, according to the simulated fracture morphology information, geological parameters and adjacent monitoring well parameters, the simulated optical fiber strain rate is obtained, including:

[0015] Determine the fracture displacement information corresponding to each time period length according to geological parameters, parameters of adjacent monitoring wells, and simulated fracture morphology information corresponding to each time period length; wherein the fracture displacement information represents the displacement of the hydraulic fracture within the time period length;

[0016] According to the fracture displacement information corresponding to the length of each time period and the parameters of the adjacent monitoring wells, the simulated optical fiber strain rate corresponding to the length of each time period is obtained.

[0017] Among them, in this application, according to the fracture displacement information corresponding to the length of each time period and the parameters of the adjacent monitoring wells, the simulated optical fiber strain rate corresponding to the length of each time period is obtained, including:

[0018] According to the crack displacement information corresponding to the length of each time period, the optical fiber strain value corresponding to the length of each time period is determined; wherein the optical fiber strain value represents the deformation of the optical fiber under stress measured by the optical fiber sensing technology;

[0019] According to the optical fiber strain value corresponding to each time period and the parameters of the adjacent monitoring wells, the simulated optical fiber strain rate corresponding to each time period is obtained.

[0020] Among them, in this application, according to the simulated optical fiber strain rate and the actual optical fiber strain rate, determining whether the simulated fracture morphology information is the actual fracture morphology information of the horizontal fracturing well includes:

[0021] determining error information between each simulated optical fiber strain rate and an actual optical fiber strain rate;

[0022] According to each error information and a preset error threshold, it is determined whether the simulated fracture morphology information is the actual fracture morphology information of the horizontal fracturing well.

[0023] Among them, in this application, according to each error information and a preset error threshold, determining whether the simulated fracture morphology information is the actual fracture morphology information of the horizontal fracturing well includes:

[0024] Performing integration processing on each error information, and comparing the value obtained after the integration processing with a preset error value threshold;

[0025] If the value obtained after the integration process is less than the preset error threshold, the simulated fracture morphology information is determined to be the actual fracture morphology information of the horizontal fracturing well;

[0026] If the value obtained after the integral processing is greater than the preset error threshold, the geological parameters are adjusted and new simulated fracture morphology information is obtained based on the adjusted geological parameters, fracturing well construction parameters, and adjacent monitoring well parameters until the value obtained after the integral processing is less than the preset error threshold.

[0027] Among them, in this application, it also includes:

[0028] Determining the serial number of a fracturing section of a fracturing crack in a horizontal fracturing well; wherein the fracturing section represents a section in a wellbore of the horizontal fracturing well;

[0029] If the sequence number of the fracturing stage is the preset first sequence number, then for each time period length, according to the crack width corresponding to the time period length and the fracturing well construction parameters, the fluid pressure in the fracture of the next time period length of the time period length is determined;

[0030] If the serial number of the fracturing stage is the preset second serial number, the proppant concentration of the fracturing stage before the fracturing stage is obtained, and the fluid pressure in the fracture of the next time period length of the time period length is determined according to the proppant concentration, the crack width corresponding to the time period length, and the fracturing well construction parameters; wherein the proppant concentration represents the concentration of the proppant in the fracturing fluid.

[0031] In a second aspect, the present application provides a three-dimensional well network fracturing crack morphology interpretation device based on distributed optical fiber monitoring, comprising:

[0032] An acquisition module is used to acquire geological parameters, fracturing well construction parameters, adjacent monitoring well parameters, and actual optical fiber strain rate; wherein the geological parameters represent geological characteristics and geological conditions; the fracturing well construction parameters represent the construction requirements for fracturing horizontal fracturing wells; the adjacent monitoring well parameters represent the well parameters of the optical fiber monitoring wells in a preset area outside the three-dimensional well network, the three-dimensional well network includes multiple horizontal fracturing wells, and the optical fiber monitoring wells are used to monitor the expansion of fracturing cracks in the horizontal fracturing wells; the actual optical fiber strain rate represents the rate at which the actually measured optical fiber length changes over time when subjected to external stress;

[0033] The first obtaining module is used to obtain simulated fracture morphology information according to geological parameters, fracturing well construction parameters, and adjacent monitoring well parameters; wherein the simulated fracture morphology information includes at least one of simulated fracture width, fracture length, and fluid pressure in the fracture;

[0034] The second obtaining module is used to obtain a simulated optical fiber strain rate according to simulated fracture morphology information, geological parameters and adjacent monitoring well parameters; wherein the simulated optical fiber strain rate represents the rate at which the simulated optical fiber length changes with time under different time period lengths;

[0035] The determination module is used to determine whether the simulated fracture morphology information is the actual fracture morphology information of the horizontal fracturing well according to the simulated optical fiber strain rate and the actual optical fiber strain rate; wherein the actual fracture morphology information includes at least one of the actual fracture width, fracture length, and fluid pressure in the fracture.

[0036] In a third aspect, the present application provides an electronic device, comprising: a processor, and a memory communicatively connected to the processor;

[0037] Memory stores computer-executable instructions;

[0038] The processor executes the computer-executable instructions stored in the memory to implement the method in the present application.

[0039] In a fourth aspect, the present application provides a computer-readable storage medium, in which computer-executable instructions are stored. When the computer-executable instructions are executed by a processor, they are used to implement the method of the present application.

[0040] The present application provides a method for interpreting fracture morphology of a three-dimensional well network based on distributed optical fiber monitoring, which obtains geological parameters, fracture well construction parameters, adjacent monitoring well parameters, and actual optical fiber strain rate; wherein the geological parameters represent geological characteristics and geological conditions; the fracture well construction parameters represent construction requirements for fractures in horizontal fracture wells; the adjacent monitoring well parameters represent well parameters of optical fiber monitoring wells within a preset area outside the three-dimensional well network, wherein the three-dimensional well network includes a plurality of horizontal fracture wells, and the optical fiber monitoring wells are used to monitor the fracture expansion of the horizontal fracture wells; the actual optical fiber strain rate represents the rate at which the actually measured optical fiber length changes with time when subjected to external stress; according to the geological parameters, the fracture well construction parameters, and the adjacent monitoring well parameters, simulated fracture morphology information is obtained; wherein the simulated fracture morphology information includes at least one of the simulated fracture width, fracture length, and fluid pressure in the fracture. By obtaining simulated fracture morphology information, the ability to monitor and interpret the hydraulic fracture extension morphology during the three-dimensional well network fracturing process can be effectively improved, thereby providing a reliable basis for understanding the fracturing transformation effect and real-time adjustment of the construction process. According to the simulated fracture morphology information, geological parameters and adjacent monitoring well parameters, the simulated optical fiber strain rate is obtained; wherein, the simulated optical fiber strain rate represents the rate at which the simulated optical fiber length changes with time under different time period lengths; according to the simulated optical fiber strain rate and the actual optical fiber strain rate, it is determined whether the simulated fracture morphology information is the actual fracture morphology information of the horizontal fracturing well; wherein, the actual fracture morphology information includes at least one of the actual fracture width, fracture length, and fluid pressure in the fracture. This method can realize the prediction and simulation of the fracture extension morphology and the evolution of the optical fiber strain signal during the three-dimensional well network fracturing process, and at the same time, by comparing the simulated optical fiber strain rate with the actual optical fiber strain rate, the hydraulic fracture extension morphology represented by it can be explained, that is, the morphological information of the actual fracture can be determined. BRIEF DESCRIPTION OF THE DRAWINGS

[0041] The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments consistent with the present application and, together with the description, serve to explain the principles of the present application.

[0042] Figure 1 A schematic diagram of a flow chart of a method for interpreting fracture morphology of a three-dimensional well network based on distributed optical fiber monitoring provided in an embodiment of the present application;

[0043] Figure 2 A schematic diagram of a flow chart of another method for interpreting fracture morphology of a three-dimensional well network based on distributed optical fiber monitoring provided in an embodiment of the present application;

[0044] Figure 3 A schematic diagram of the expansion morphology of the three-dimensional well pattern fracturing cracks provided in the embodiment of the present application;

[0045] Figure 4A schematic diagram of the simulation results of the single-cluster crack extension morphology provided in the embodiment of the present application;

[0046] Figure 5 The fracture propagation simulation results of a fracturing stage with only one perforation cluster provided in the embodiment of the present application;

[0047] Fig. 6A A schematic diagram of the displacement field induced by a cluster of crack extensions in adjacent optical fiber monitoring wells provided in an embodiment of the present application;

[0048] Figure 6B A schematic diagram of a fiber strain (value) signal induced by a cluster of crack extensions in adjacent fiber monitoring wells provided in an embodiment of the present application;

[0049] Figure 6C A schematic diagram of strain rate signals induced by a cluster of crack extensions in adjacent optical fiber monitoring wells provided in an embodiment of the present application;

[0050] Figure 7 A schematic diagram of a simulation result of fracture propagation with multiple perforation clusters in a fracturing stage provided in an embodiment of the present application;

[0051] Fig. 8A A schematic diagram of simulation results of distributed optical fiber strain induced in adjacent optical fiber monitoring wells when multiple clusters of cracks extend synchronously provided in an embodiment of the present application;

[0052] Figure 8B A schematic diagram of simulation results of distributed optical fiber strain rate signals induced in adjacent optical fiber monitoring wells when multiple clusters of fractures extend synchronously provided in an embodiment of the present application;

[0053] Fig. 9 A schematic diagram of the structure of a three-dimensional well network fracturing crack morphology interpretation device based on distributed optical fiber monitoring provided in an embodiment of the present application;

[0054] Fig.10 A schematic diagram of the structure of an electronic device provided in an embodiment of the present application.

[0055] The above drawings have shown clear embodiments of the present application, which will be described in more detail later. These drawings and text descriptions are not intended to limit the scope of the present application in any way, but to illustrate the concept of the present application to those skilled in the art by referring to specific embodiments. DETAILED DESCRIPTION

[0056] Exemplary embodiments will be described in detail herein, examples of which are shown in the accompanying drawings. When the following description refers to the drawings, the same numbers in different drawings represent the same or similar elements unless otherwise indicated. The implementations described in the following exemplary embodiments do not represent all implementations consistent with the present application. Instead, they are merely examples of devices and methods consistent with some aspects of the present application as detailed in the appended claims.

[0057] At present, during the three-dimensional well network fracturing process, although the optical fiber strain signal induced by the crack expansion in the fracturing well can be monitored in real time in the adjacent monitoring wells, there is a lack of a complete and efficient process to confirm the crack morphology information through the optical fiber strain signal.

[0058] The present application provides a method, device, equipment and storage medium for interpreting fracture morphology of a three-dimensional well network based on distributed optical fiber monitoring, which obtains geological parameters, fracture well construction parameters, adjacent monitoring well parameters, and actual optical fiber strain rate; wherein the geological parameters represent geological characteristics and geological conditions; the fracture well construction parameters represent the construction requirements for fractures in horizontal fracture wells; the adjacent monitoring well parameters represent the well parameters of the optical fiber monitoring wells in a preset area outside the three-dimensional well network, wherein the three-dimensional well network includes multiple horizontal fracture wells, and the optical fiber monitoring wells are used to monitor the fracture expansion of the horizontal fracture wells; the actual optical fiber strain rate represents the rate at which the actually measured optical fiber length changes over time when subjected to external stress; according to the geological parameters, the fracture well construction parameters, and the adjacent monitoring well parameters, simulated fracture morphology information is obtained; wherein, the simulated fracture morphology information is obtained. The simulated fracture morphology information includes at least one of the simulated fracture width, fracture length, and fluid pressure in the fracture; by obtaining the simulated fracture morphology information, the fine monitoring and interpretation capabilities of the hydraulic fracture extension morphology during the three-dimensional well network fracturing process can be effectively improved, thereby providing a reliable basis for understanding the fracturing transformation effect and real-time adjustment of the construction process, and obtaining the simulated optical fiber strain rate according to the simulated fracture morphology information, geological parameters and adjacent monitoring well parameters; wherein the simulated optical fiber strain rate represents the rate at which the simulated optical fiber length changes with time under different time period lengths; according to the simulated optical fiber strain rate and the actual optical fiber strain rate, it is determined whether the simulated fracture morphology information is the actual fracture morphology information of the horizontal fracturing well; wherein the actual fracture morphology information includes at least one of the actual fracture width, fracture length, and fluid pressure in the fracture. This method can realize the prediction and simulation of the fracture extension morphology and the evolution of the optical fiber strain signal during the three-dimensional well network fracturing process, and at the same time, by comparing the simulated optical fiber strain rate with the actual optical fiber strain rate, the hydraulic fracture extension morphology represented by it can be interpreted, that is, the morphological information of the actual fracture can be determined.

[0059] Among them, the three-dimensional well network refers to the three-dimensional network structure formed by arranging multiple wells underground during the development of oil and gas fields. This well network design aims to maximize the extraction efficiency and economic benefits of oil and gas resources while minimizing damage to the formation and environmental impact.

[0060] A horizontal fracturing well is a special type of oil and gas well in which the wellbore extends horizontally underground, unlike traditional vertical wells.

[0061] Monitoring wells are special wells used to monitor groundwater, geological conditions, reservoir dynamics, and fracturing fluid diffusion. The location selection of monitoring wells is a key step because it directly affects the accuracy and effectiveness of monitoring data. During oil and gas field development and hydraulic fracturing, the reasonable arrangement of monitoring wells can provide valuable information to help optimize development plans and ensure environmental safety.

[0062] Distributed fiber optic measurement is a technology that uses optical fiber as a sensing medium to perform continuous measurements along the entire length of the fiber.

[0063] Figure 1 A schematic diagram of a flow chart of a method for interpreting fracture morphology of a three-dimensional well network based on distributed optical fiber monitoring provided in an embodiment of the present application. Figure 1 As shown, the execution subject of the method can be a server or other servers, and this embodiment is not particularly limited here. Figure 1 As shown, the method includes:

[0064] S101. Obtain geological parameters, fracturing well construction parameters, adjacent monitoring well parameters, and actual optical fiber strain rate; wherein the geological parameters represent geological characteristics and geological conditions; the fracturing well construction parameters represent the construction requirements for fracturing horizontal fracturing wells; the adjacent monitoring well parameters represent the well parameters of the optical fiber monitoring wells within a preset area outside the three-dimensional well network, wherein the three-dimensional well network includes multiple horizontal fracturing wells, and the optical fiber monitoring wells are used to monitor the expansion of fracturing cracks in the horizontal fracturing wells; and the actual optical fiber strain rate represents the rate at which the actually measured optical fiber length changes over time when subjected to external stress.

[0065] Among them, geological parameters refer to numerical or qualitative indicators that describe various physical, chemical and mechanical properties of geological bodies and geological processes. These parameters play an important role in geological exploration, engineering construction, environmental protection and other fields. Geological parameters include: Young's modulus, Poisson's ratio, fracture toughness, three-dimensional geostress distribution, etc. Young's modulus, also known as elastic modulus, is a physical quantity that describes the relationship between stress and strain of a material in the elastic deformation stage. Poisson's ratio is an important parameter in material mechanics, which is used to describe the relationship between lateral deformation and longitudinal deformation of a material when it is subjected to stress. Fracture toughness is the ability of a material to resist crack propagation and is an important parameter to measure the ability of a material to withstand stress in the presence of cracks or defects. Three-dimensional geostress refers to three mutually perpendicular stress components existing at a point, which characterizes the pressure on the stratum from different directions. In this application, the center point of each fracture grid unit is used as the stress point.

[0066] The construction parameters of fracturing wells refer to the various technical indicators and operating parameters that need to be monitored and controlled during the fracturing operation of oil and gas wells. The construction parameters of fracturing wells include: the number of horizontal fracturing wells, the length of horizontal sections, the length of fracturing sections, the number of perforation clusters, the construction displacement, the amount of fracturing fluid, the combination of liquid viscosity, the injection concentration of proppant, etc. The number of horizontal fracturing wells refers to the number of horizontal fracturing wells contained in the three-dimensional well network. The horizontal section length refers to the length of the horizontal fracturing well extending horizontally from the wellbore to the end point. The horizontal fracturing well is divided into multiple independent parts, each of which is called a fracturing section, and the length of each fracturing section is the fracturing section length. The number of perforation clusters refers to the number of perforation clusters arranged in a fracturing section, and the number of perforation clusters directly affects the distribution and morphology of cracks. Reasonable number and arrangement of perforation clusters can form uniform cracks. The construction displacement refers to the total amount of fracturing fluid, which is the liquid used to generate and expand cracks during hydraulic fracturing. The main function of fracturing fluid is to transfer high pressure to the reservoir rock, form cracks, and carry proppants (such as sand or ceramsite) into the cracks to keep them open. The fracturing fluid volume refers to the speed at which the fracturing fluid is injected into the horizontal fracturing well. The liquid viscosity combination refers to the liquid with the required viscosity obtained by mixing liquids of different viscosities. Liquid viscosity refers to the magnitude of the internal resistance of the liquid during the flow process. It is an important physical parameter for measuring the fluidity of the liquid. The proppant injection concentration refers to the concentration of proppants (such as sand or ceramic particles) in the fracturing fluid during the hydraulic fracturing process. It refers to the injection of fracturing fluid through the injection point, and the fracturing fluid contains proppants. The proppant concentration refers to the proportion of proppants in the fracturing fluid during the hydraulic fracturing process. There are also proppants laid in the cracks. The concentration in the cracks is called the proppant concentration.

[0067] Adjacent monitoring well parameters Adjacent monitoring well parameters refer to various technical indicators and operating parameters of wells used to monitor the geology and fluid dynamics of adjacent areas during oil and gas field development, groundwater management, environmental monitoring, etc. Such wells used to monitor the geology and fluid dynamics of adjacent areas can be called adjacent monitoring wells. In this embodiment, adjacent monitoring wells can refer to fiber optic monitoring wells. These parameters help to understand the formation pressure, fluid flow, pollution diffusion, etc., so as to optimize the development plan and protect the environment. Adjacent monitoring well parameters include: monitoring well location, monitoring section length, distributed fiber optic measurement distance, etc. The monitoring section length refers to the length of a specific well section used for monitoring in a monitoring well.

[0068] The actual optical fiber strain rate is obtained by detecting the actual optical fiber strain rate in the adjacent well. The simulated optical fiber strain rate is compared with the actual optical fiber strain rate to confirm the fracture morphology information.

[0069] S102, obtaining simulated fracture morphology information according to geological parameters, fracturing well construction parameters, and adjacent monitoring well parameters; wherein the simulated fracture morphology information includes at least one of simulated fracture width, fracture length, and fluid pressure in the fracture.

[0070] Simulated fracture morphology information refers to various parameters that simulate the geometric characteristics and distribution of fractures in geological bodies or engineering structures. This information is important for understanding the formation mechanism of fractures, predicting the expansion behavior of fractures, and evaluating their impact on fluid flow and mechanical properties. By obtaining simulated fracture morphology information, it is possible to guide the timely adjustment of fracturing construction parameters, thereby increasing development benefits.

[0071] Among them, in the embodiment of the present application, according to the geological parameters, the construction parameters of the fracturing well, and the parameters of the adjacent monitoring wells, the simulated fracture morphology information is obtained, including:

[0072] Determine the initial time period length according to the preset initial crack length; wherein the time period length represents the injection of liquid into the horizontal fracturing well within the range of the time period length;

[0073] Determine the crack width, crack length, and fluid pressure in the crack corresponding to the next time period length according to the initial time period length, the preset initial crack width, and the fracturing well construction parameters, and continue to determine the new next time period length according to the crack length corresponding to the next time period length;

[0074] Until the total volume of liquid injected in all the determined time periods reaches the preset volume, the crack width, crack length, and fluid pressure in the crack corresponding to the last time period are obtained, which is the simulated crack morphology information.

[0075] The time period length can be a time step. By presetting the length of the rectangular grid and the width of the rectangular grid, a rectangular grid unit is obtained, and then the rectangular grid is used as the area to be expanded of the crack. The rectangular grid unit is divided into an injection point unit, a channel unit, and a tip unit. The center point of each grid unit has a corresponding spatial coordinate (x j , y j , z j ). By presetting a spatial coordinate A, a rectangular grid unit A1 is confirmed as the injection point of the fracturing fluid, and the initial crack length is the length of A1 (i.e., the length of a grid). Considering that the optical fiber is a slender material that can only deform axially, the optical fibers in adjacent monitoring wells are divided into one-dimensional line segment units, and the center of each line segment unit also corresponds to a spatial coordinate. The preset initial crack width is preset, and the value is usually very small, for example: set to 1e-5m.

[0076] The injected liquid is fracturing fluid. The fracturing fluid injection time refers to the total time of injecting fracturing fluid into the well during the fracturing operation. The fracturing fluid injection time needs to be precisely controlled and monitored in real time to optimize the fracture morphology and conductivity, and improve the effect and economic benefits of the fracturing operation. Therefore, the fracturing fluid injection time is divided into multiple time periods, and the length of each time period is adjusted.

[0077] The initial time period length can be preset or obtained according to the formula:

[0078] ;

[0079] in, is the initial time period length, is the length of the crack grid unit, The width of the crack grid unit, G is the shear modulus, v is the Poisson's ratio, is the liquid viscosity, is the preset initial crack width.

[0080] The time period length meets the following requirements:

[0081] ;

[0082] in, is the relaxation factor, , is the length of the crack grid unit, is the width of the crack grid unit, is the crack length, is the expansion speed in the x direction,

[0083] is the expansion speed in the y direction, which is obtained by dividing the crack length by the long time of all time periods. is the time step.

[0084] The preset volume refers to the total amount of fracturing fluid, which is the construction displacement in the construction parameters. After the total amount of fracturing fluid is injected into the fracturing well according to the fracturing fluid volume (i.e., the fracturing fluid injection rate), the corresponding crack width, crack length, and fluid pressure in the crack are obtained as simulated crack morphology information.

[0085] By setting the parameters based on geological parameters, fracturing well construction parameters and adjacent monitoring well parameters, the simulated fracture morphology information can be obtained, which can achieve accurate prediction, optimize construction, improve efficiency, reduce environmental impact, increase recovery rate and safety and other technical effects, providing strong technical support for oil and gas field development.

[0086] In the embodiment of the present application, it also includes:

[0087] Determining the serial number of a fracturing section of a fracturing crack in a horizontal fracturing well; wherein the fracturing section represents a section in a wellbore of the horizontal fracturing well;

[0088] If the sequence number of the fracturing stage is the preset first sequence number, then for each time period length, according to the crack width corresponding to the time period length and the fracturing well construction parameters, the fluid pressure in the fracture of the next time period length of the time period length is determined;

[0089] If the serial number of the fracturing stage is the preset second serial number, the proppant concentration of the fracturing stage before the fracturing stage is obtained, and the fluid pressure in the fracture of the next time period length of the time period length is determined according to the proppant concentration, the crack width corresponding to the time period length, and the fracturing well construction parameters; wherein the proppant concentration represents the concentration of the proppant in the fracturing fluid.

[0090] Among them, the fracturing stage refers to the multiple independent areas into which the horizontal fracturing well is divided during the fracturing operation, and each area is subjected to a separate fracturing operation. In a multi-stage fracturing operation, the closure of the cracks in the first stage of fracturing (i.e., the first fracturing stage) will produce an induced stress field in the subsequent fracturing stage operation process, thereby affecting the fluid pressure in the fractures of the subsequent fracturing. Therefore, it is necessary to determine whether there is a fracturing stage before the current fracturing stage.

[0091] In this embodiment, the preset first serial number may refer to the first fracturing stage, that is, the current fracturing stage is the first fracturing stage to be fractured in the horizontal fracturing well, and there is no other fracturing stage before the current fracturing stage.

[0092] The preset second serial number refers to other fracturing stages other than the first fracturing stage, that is, the current fracturing stage is not the first fracturing stage to be fractured in the horizontal fracturing well, and there are other fracturing stages before the current fracturing stage.

[0093] When the current fracturing stage is the first fracturing stage of the horizontal fracturing well, the rock solid deformation equation induced by the fracture is described by the three-dimensional displacement discontinuity method, and the relationship matrix between the fracture width and the induced stress can be established. Then, the pressure balance condition for any fracture grid unit can be expressed as:

[0094] ;

[0095] Among them, P s is the tangential stress of the fracture grid unit, is the normal stress of the fracture grid unit. According to the fracture boundary stress equilibrium condition, the fluid pressure P in the fracture is equal to the sum of the induced stress on the fracture and the formation closure stress, which can be calculated by the following three-dimensional displacement discontinuity matrix:

[0096]

[0097] in, is the formation closure stress, which is one of the three-dimensional ground stress combinations. D1 is the tangential displacement discontinuity. D3 is the normal displacement discontinuity of the fracture unit, which is also the width of the fracture. The longest D3 in the first time period is the initial fracture width, and A is the influence coefficient matrix.

[0098] The mass conservation equation of fluid flow in hydraulic fractures can describe the relationship between the fluid pressure in the fracture and the fracture width:

[0099]

[0100]

[0101] Where w is the crack width, t is the time, that is, the sum of the lengths of all time periods, P is the fluid pressure in the crack, and C L is the fluid loss rate, Q is the liquid pump displacement, is the Kronecker symbol, which represents the coordinates of the preset injection point coordinates before the fracturing fluid is injected, u is the fluid viscosity (i.e. liquid viscosity), is the normalized proppant concentration in the fracture, is the proppant flux, The proppant injection concentration is calculated based on the structured rectangular grid cells and the fluid flow mass conservation equation is discretized by the finite volume method:

[0102]

[0103] According to the mass conservation equation of fluid flow in hydraulic fractures, the mass conservation equation of discrete fluid flow can be calculated based on the current fracture width w n (w n Equal to the crack normal displacement discontinuity D3; w sThe tangential displacement in the horizontal direction of the crack is equal to D1) and the grid unit width w of the next time period is calculated. n+1 :

[0104] ;

[0105] Among them, M is the coefficient matrix and S is the source-sink function.

[0106] According to the new crack width w n+1 , i.e. D3, is substituted into the three-dimensional displacement discontinuity equation to obtain:

[0107] ;

[0108] By iteratively solving the linear equations, the tangential displacement discontinuity D1 corresponding to the crack grid unit can be calculated, that is, w s+1 Then continue to change the new crack width w n+1 (i.e. D3) and the new tangential seam width w s+1 (i.e. D1) can calculate the fluid pressure in the fracture at the new moment. Therefore, according to the above fluid-solid coupling equation, the width of all fracture unit grids and the fluid pressure in the fracture at the next moment can be obtained according to the fracture width and the fluid pressure field in the fracture at any moment.

[0109] When the current fracturing stage is not the first fracturing stage of the horizontal fracturing well, the cracks formed by the first fracturing can be divided into supported crack areas and unsupported crack areas according to the distribution of proppant in the cracks (i.e., whether the proppant concentration in the cracks is 0). For the supported crack areas (i.e., the proppant concentration in the cracks is not 0), the proppant supports the crack wall, and the extrusion stress on the proppant sand pile is It can be expressed as:

[0110] ;

[0111] in, To support the paving concentration, is a constant determined by the proppant stacking morphology, , , is the initial width of the fracture supported by the proppant sand pile, and .

[0112] For the unsupported fracture area (i.e., the fracture proppant concentration is 0), the final degree of fracture closure is determined only by the roughness of the fracture surface. The contact stress of the rough fracture surface is It can be expressed as:

[0113] ;

[0114] in, is the crack surface roughness, and is the empirical coefficient.

[0115] Establish the matrix equation of the propped fractures and unpropped fractures in the first fracturing stage:

[0116] ;

[0117]

[0118] in, is the formation closure stress; A is the influence coefficient matrix; is the residual width of the fracture supported by the first fracturing stage; is the residual width of the unsupported crack in the first fracturing stage; the residual width of the crack can be obtained by iteratively solving the above nonlinear equations .

[0119] The fluid pressure in the seam can be:

[0120] ;

[0121] The advantage of this setting is that by determining the sequence number of the fracturing section of the fracturing crack in the horizontal fracturing well, the fluid pressure in the fracture can be calculated and predicted more accurately, thereby optimizing the fracturing construction process and improving the production capacity of the oil and gas well.

[0122] S103, obtaining a simulated optical fiber strain rate according to simulated fracture morphology information, geological parameters and adjacent monitoring well parameters; wherein the simulated optical fiber strain rate represents the rate at which the simulated optical fiber length changes with time under different time period lengths.

[0123] By substituting the simulated fracture morphology information, geological parameters and adjacent detection well parameters into the preset formula, the optical fiber strain rate can be obtained.

[0124] Among them, in the embodiment of the present application, the simulated optical fiber strain rate is obtained according to the simulated fracture morphology information, geological parameters and adjacent monitoring well parameters, including:

[0125] Determine the fracture displacement information corresponding to each time period length according to geological parameters, parameters of adjacent monitoring wells, and simulated fracture morphology information corresponding to each time period length; wherein the fracture displacement information represents the displacement of the hydraulic fracture within the time period length;

[0126] According to the fracture displacement information corresponding to the length of each time period and the parameters of the adjacent monitoring wells, the simulated optical fiber strain rate corresponding to the length of each time period is obtained.

[0127] Among them, each time period length corresponds to a simulated fracture morphology information. The simulated fracture morphology information corresponding to each time period length includes the tangential displacement of the fracture level corresponding to each time period length (i.e. D1), and the fracture normal displacement (i.e. D3, also the fracture width), and the adjacent monitoring well parameters include Poisson's ratio and Young's modulus (which can be used to calculate the shear modulus).

[0128] Through the crack displacement information and adjacent detection well parameters of each time period, the induced displacement of the optical fiber detection point caused by each crack grid in each time period can be obtained. The word "induced" in "induced displacement" means an adjective, which means the displacement of any optical fiber monitoring point in the adjacent detection well caused by crack expansion. The same is true for induced stress. Crack expansion will produce induced stress and induced displacement. This induced stress or displacement can exist between cracks or at any point. The fluid pressure in the crack contains induced stress. When calculating the fluid-solid coupling of crack expansion, the induced stress between cracks is considered. Here, optical fiber is used to monitor crack expansion and calculate the induced displacement caused by crack expansion on the optical fiber. Optical fiber is a line. The line is discretized into many points, called optical fiber monitoring points. The induced displacement of each point is calculated. The induced displacement of each point is added to get the total displacement at the optical fiber monitoring point. According to the total displacement at the optical fiber monitoring point, the simulated optical fiber strain rate corresponding to each time period can be confirmed.

[0129] During the fracturing process, the expansion of the crack will continuously induce displacement of the adjacent fiber optic monitoring wells, thereby generating strain signals. For each time period, the displacement induced by each crack grid unit at the fiber optic detection point is:

[0130] ;

[0131] in, is the induced displacement of the optical fiber axis caused by crack unit i, , , , is the derivative of the kernel function of I. Induced displacement usually refers to the displacement or deformation that occurs in the formation or fracture due to the injection and pressure of fracturing fluid during the fracturing process of oil and gas wells. Induced displacement is a key parameter in fracturing design and construction, which directly affects the formation, expansion and support effect of fractures.

[0132] ;

[0133]

[0134]

[0135] in, and is the local coordinate of the grid unit, obtained according to the location of the detection well, a and b are the half-length of the grid, .

[0136] Considering that the number of hydraulic fracture grid units in the current time period is N, the induced displacement of each unit on the optical fiber monitoring point can be calculated by the above formula, and then the total displacement of the optical fiber monitoring point j in the current time period can be obtained by the superposition principle.

[0137] ;

[0138] By analogy, the total displacement at each optical fiber monitoring point corresponding to each time period is obtained, and the simulated optical fiber strain rate corresponding to each time period is obtained according to the fracture displacement information corresponding to each time period and the parameters of the adjacent monitoring wells.

[0139] The advantage of this setting is that by combining geological parameters and adjacent monitoring well parameters to simulate the optical fiber strain rate, it is possible to more accurately monitor and evaluate the fracture behavior and formation response during the fracturing process, optimize the fracturing design and construction process, and improve the production capacity and construction safety of oil and gas wells. It has significant technical effects and application value.

[0140] Among them, in the embodiment of the present application, according to the fracture displacement information corresponding to the length of each time period and the parameters of the adjacent monitoring wells, the simulated optical fiber strain rate corresponding to the length of each time period is obtained, including:

[0141] According to the crack displacement information corresponding to the length of each time period, the optical fiber strain value corresponding to the length of each time period is determined; wherein the optical fiber strain value represents the deformation of the optical fiber under stress measured by the optical fiber sensing technology;

[0142] According to the optical fiber strain value corresponding to each time period and the parameters of the adjacent monitoring wells, the simulated optical fiber strain rate corresponding to each time period is obtained.

[0143] in, is the axial displacement of the optical fiber monitoring point j on the optical fiber monitoring well. In the actual optical fiber strain monitoring of adjacent wells, the average strain disturbance of the optical fiber over a certain measuring distance is obtained. The optical fiber strain value can be simulated and calculated based on the total displacement of the optical fiber monitoring point:

[0144] ;

[0145] in, is the optical fiber strain value at the optical fiber detection point j, L is the optical fiber measurement distance, It is the displacement u between point j and point j+1. Similarly, It is the displacement u between point j and point j-1.

[0146] According to the degree of strain per unit time (i.e. the strain value per unit time), the simulated optical fiber strain rate is obtained:

[0147] ;

[0148] The advantage of this setting is that by combining the fracture displacement information and the parameters of the adjacent monitoring wells, the optical fiber strain rate can be accurately simulated, which can achieve high-precision monitoring and optimization of the fracturing process, improve the production capacity and construction safety of oil and gas wells, and has significant technical effects and application value.

[0149] S104. Determine whether the simulated fracture morphology information is actual fracture morphology information of the horizontal fracturing well according to the simulated optical fiber strain rate and the actual optical fiber strain rate; wherein the actual fracture morphology information includes at least one of actual fracture width, fracture length, and fluid pressure in the fracture.

[0150] The simulated optical fiber strain rate corresponds to the simulated fracture morphology information, and the actual optical fiber strain rate corresponds to the actual fracture morphology information. Therefore, by comparing the simulated optical fiber strain rate with the actual optical fiber strain rate, it can be confirmed whether the simulated fracture morphology information is the actual fracture morphology information of the horizontal fracturing well.

[0151] Among them, in the embodiment of the present application, determining whether the simulated fracture morphology information is the actual fracture morphology information of the horizontal fracturing well according to the simulated optical fiber strain rate and the actual optical fiber strain rate includes:

[0152] determining error information between each simulated optical fiber strain rate and an actual optical fiber strain rate;

[0153] According to each error information and a preset error threshold, it is determined whether the simulated fracture morphology information is the actual fracture morphology information of the horizontal fracturing well.

[0154] Among them, after the actual work is completed, the optical fiber strain rate signal in the monitoring well can be obtained. The optical fiber strain rate simulated by the numerical model is compared with the optical fiber strain rate actually monitored on site to obtain the optical fiber strain rate error (i.e. error information) at time t. :

[0155] ;

[0156] in, To simulate the strain rate of the jth distributed optical fiber strain monitoring point, is the actual optical fiber strain rate.

[0157] The benefit of this setting is that by comparing the simulated optical fiber strain rate with the actual optical fiber strain rate, it is determined whether the simulated fracture morphology information is the actual fracture morphology information of the horizontal fracturing well, which can achieve accurate verification and adjustment of the fracture morphology, improve the scientificity and reliability of fracturing design and construction, enhance construction safety, and increase the production capacity of oil and gas wells. It has significant technical effects and application value.

[0158] Among them, in the embodiment of the present application, according to each error information and a preset error threshold, determining whether the simulated fracture morphology information is the actual fracture morphology information of the horizontal fracturing well includes:

[0159] Performing integration processing on each error information, and comparing the value obtained after the integration processing with a preset error value threshold;

[0160] If the value obtained after the integration process is less than the preset error threshold, the simulated fracture morphology information is determined to be the actual fracture morphology information of the horizontal fracturing well;

[0161] If the value obtained after the integral processing is greater than the preset error threshold, the geological parameters are adjusted and new simulated fracture morphology information is obtained based on the adjusted geological parameters, fracturing well construction parameters, and adjacent monitoring well parameters until the value obtained after the integral processing is less than the preset error threshold.

[0162] Among them, the strain rate error of the optical fiber is The total error is obtained by integrating over a given pumping time T (i.e., the total time period of the injected liquid). (That is, the value obtained after product processing):

[0163] ;

[0164] The preset error threshold may be any smaller percentage, for example, 5%.

[0165] When the total error is less than the error threshold, the simulated fracture morphology information is the actual fracture morphology information of the horizontal fracturing well.

[0166] When the total error is greater than the error threshold, the geological parameters need to be adjusted until the total error is less than the error threshold, and the simulated fracture morphology information is used as the actual fracture morphology information of the horizontal fracturing well. Usually, each parameter belonging to the geological parameters has a certain range, and there are multiple combinations when each parameter belonging to the geological parameters meets the range. The adjustment criteria are mainly based on the fracture extension morphology and the optical fiber monitoring results. The approximate fracture morphology can be preliminarily determined according to the actual optical fiber monitoring results, and the numerical simulation can also obtain the calculated simulated fracture morphology. When the calculated fracture morphology (length / height / fracture width, the fracture height is the y of the fracture grid) exceeds the shape estimated according to the actual optical fiber monitoring results, the fracture toughness / three-dimensional ground stress can be increased, and the Young's modulus can be reduced; when the calculated fracture morphology (length / height / fracture width) is less than the shape estimated according to the actual optical fiber monitoring results, the fracture toughness / three-dimensional ground stress can be reduced, and the Young's modulus can be increased; of course, such parameter changes are within a certain range given in advance, and how to adjust needs to rely on the experience of numerical simulation of fracture extension, and finally the optimal result is quantitatively selected based on the error results.

[0167] The advantage of this setting is that by integrating the error information and comparing it with the preset error threshold, it is determined whether the simulated fracture morphology information is the actual fracture morphology information of the horizontal fracturing well, which can achieve accurate verification and dynamic adjustment of the fracture morphology, improve the scientificity and reliability of fracturing design and construction, enhance construction safety, and increase the production capacity of oil and gas wells, with significant technical effects and application value.

[0168] An embodiment of the present application provides a method for interpreting fracture morphology of a three-dimensional well network based on distributed optical fiber monitoring. By comparing a simulated optical fiber and strain rate with an actual optical fiber strain rate, for a case where the simulated optical fiber and strain rate and the actual optical fiber strain rate are less than a threshold, the actual fracture morphology information of the horizontal fracturing well is confirmed, thereby obtaining the fracture morphology information of the three-dimensional well network. For a case where the simulated optical fiber and strain rate and the actual optical fiber strain rate are less than a threshold, the geological parameters can be adjusted.

[0169] Figure 2 A schematic diagram of another flow chart of a method for interpreting fracture morphology of a three-dimensional well network based on distributed optical fiber monitoring provided in an embodiment of the present application. Figure 2 As shown, the execution subject of the method can be a server or other servers, and this embodiment is not particularly limited here. Figure 2 As shown, the method includes:

[0170] S201. Obtain basic parameters, wherein the basic parameters include geological parameters, fracturing well construction parameters, and adjacent monitoring well parameters.

[0171] Among them, geological parameters include: Young's modulus, Poisson's ratio, fracture toughness, and three-dimensional geostress distribution; fracturing well construction parameters include: number of horizontal fracturing wells, horizontal section length, fracturing section length, number of perforation clusters, cluster combination, perforation parameters, construction displacement, fracturing fluid volume, liquid viscosity combination, and fracturing fluid concentration; adjacent monitoring well parameters include: monitoring well location, monitoring section length, and distributed optical fiber measurement distance.

[0172] S202, obtaining structured grid units and line segment units, and calculating a time step, and injecting fracturing fluid into the well within the time step, wherein the structured grid units are used to characterize cracks, and the line segment units are used to characterize optical fibers in adjacent monitoring wells.

[0173] Among them, the sum of all time steps is the total time of fracturing fluid injection. After the previous time step ends, the next time step needs to be calculated.

[0174] The structured grid cells are obtained according to the preset gateway cell length and width.

[0175] The time period length meets the following requirements:

[0176]

[0177] in, is the relaxation factor, , is the length of the crack grid element, The width of the crack mesh element, is the crack length, is the expansion speed in the x direction, is the expansion speed in the y direction, which is obtained by dividing the crack length by the long time of all time periods. is the time step.

[0178] S203: Determine whether the fracturing block corresponding to the fracturing crack is the first fracturing block to be fractured.

[0179] S204A: If the fracturing block corresponding to the fracturing crack is the first fracturing block to be fractured, the width of the fracturing crack and the fluid pressure in the crack in the three-dimensional well pattern are calculated.

[0180] The method for calculating the width of the hydraulic fracture and the fluid pressure in the fracture in the three-dimensional well pattern is:

[0181] As the fracturing fluid is injected, the fluid pressure and width in the hydraulic fracture change continuously, and both satisfy the coupled equations of rock solid deformation and fluid flow in the fracture.

[0182] The rock solid deformation equation induced by hydraulic fractures is described by the three-dimensional displacement discontinuity method. The normal displacement discontinuity D3 and the tangential displacement discontinuities D1 and D2 of the fracture unit are expressed as:

[0183] (Formula 1)

[0184] Among them, the normal displacement discontinuity D3 is the fracture width. For any grid unit, its displacement discontinuity will induce normal stress and tangential stress at any point in the reservoir, which can be expressed as:

[0185] (Formula 2)

[0186] in, is the induced normal stress in the local coordinate system, is the shear force in the local coordinate system, for:

[0187] (Formula 3)

[0188] Where G is the shear modulus, MPa, calculated from Poisson's ratio and Young's modulus, and v is Poisson's ratio, dimensionless.

[0189] I is the kernel function of the constant displacement discontinuous grid cell with respect to a rectangular grid cell:

[0190] (Formula 4) , , are the first-order, second-order and third-order partial derivatives of kernel function I in the local coordinate system x1x2x3, respectively. x1x2x3 represents xyz in the coordinate system. According to the principle of induced stress superposition, the induced stress on any point or any grid unit i is the superposition of the induced stress generated by all crack units. After the local coordinate system and the global coordinate system are transformed into each other, the induced stress on the grid unit i can be expressed by the following matrix:

[0191] (Formula 5)

[0192] in, is the induced normal stress in global coordinates, , is the induced tangential stress in the global coordinate system, N is the number of activated fracture grid elements, and A is the influence coefficient matrix, which can be derived from (Formula 2). Considering that the fracture is a non-planar fracture, that is, the fracture does not deflect in the fracture height direction, then and D2 are both 0, (Formula 5) can be further simplified.

[0193] After establishing the relationship between crack width and induced stress according to the above three-dimensional displacement discontinuity method, the pressure balance condition for any crack grid unit can be expressed as:

[0194] (Formula 6)

[0195] Among them, P s is the tangential stress of the fracture grid unit, P n is the normal stress of the fracture grid unit. According to the fracture boundary stress equilibrium condition, the fluid pressure P in the fracture is equal to the sum of the induced stress on the fracture and the formation closure stress, which can be calculated by the following three-dimensional displacement discontinuity matrix:

[0196] (Formula 7)

[0197] in, It is the formation closure stress and one of the three-dimensional geostress.

[0198] The mass conservation equation of fluid flow in hydraulic fractures can describe the relationship between the fluid pressure in the fracture and the fracture width:

[0199] (Formula 8)

[0200] (Formula 9)

[0201] Where w is the crack width, t is the time, that is, the sum of the lengths of all time periods, P is the fluid pressure in the crack, and C L is the fluid loss rate, Q is the liquid pump displacement, is the Kronecker symbol, which represents the coordinates of the preset injection point coordinates before the fracturing fluid is injected, u is the fluid viscosity (i.e. liquid viscosity), is the normalized proppant concentration in the fracture, is the proppant flux, is the proppant injection concentration. Based on the structured rectangular grid unit, the fluid flow mass conservation equation is discretized by the finite volume method:

[0202] (Formula 10)

[0203] Substituting (Formula 7) into (Formula 8), we can get the value of the current crack width w n (w n Equal to the crack normal displacement discontinuity D3; w s is the tangential displacement of the crack in the horizontal direction, equal to D1), is the time step, calculate the grid cell width w of the next time step n+1 :

[0204] (Formula 11)

[0205] Among them, M is the coefficient matrix, S is the source-sink function, both of which can be obtained from (Formula 8), which is discretized into (Formula 10) through (Formula 8), and (Formula 10) is further abbreviated as (Formula 11), where M and S are abbreviated symbols.

[0206] Then the new crack width w n+1 , i.e. D3, is substituted into the three-dimensional displacement discontinuity equation (Formula 6), and we get:

[0207] (Formula 12)

[0208] By iteratively solving the linear equations, the tangential displacement discontinuity D1 corresponding to the crack grid unit can be calculated, that is, w s+1 Then continue to change the new crack width w n+1 (i.e. D3) and the new tangential seam width w s+1 (i.e. D1) is substituted into (Formula 7) to calculate the fluid pressure in the fracture at the new moment. Therefore, according to the above fluid-solid coupling equation, the width of all fracture unit grids and the fluid pressure in the fracture at the next moment can be obtained according to the fracture width and the fluid pressure field in the fracture at any moment.

[0209] S204B, if the fracturing block corresponding to the fracturing crack is not the first fracturing block to be fractured, calculate the closure degree of the first fracturing section crack, and obtain the fracturing crack width and the fluid pressure in the crack in the three-dimensional well pattern according to the closure degree of the first fracturing section crack.

[0210] If it is determined that the crack will expand in the current time step, the crack units around the tip unit will be activated. It is the angle between the unit to be activated and the current tip unit, also known as the crack extension direction. The purpose of this is not only to gradually activate the crack and expand the crack during the calculation process, but also to adjust the crack extension direction in real time.

[0211] Among them, the method for obtaining the degree of crack closure in the first fracturing stage is:

[0212] According to the distribution of proppant in the crack, the crack formed by the initial fracturing can be divided into the supported crack area and the unsupported crack area. In the supported crack area, the proppant supports the crack wall, and the extrusion stress on the proppant sand pile It can be expressed as:

[0213] (Formula 16)

[0214] Among them, among them, To support the paving concentration, is a constant determined by the proppant stacking morphology, , , is the initial width of the fracture supported by the proppant sand pile, and w0 is the crack width of the first fracture to complete the fracturing time step. For the unsupported fracture area, the final degree of crack closure is only determined by the roughness of the fracture surface. The contact stress of the rough fracture surface It can be expressed as:

[0215] (Formula 17)

[0216] in, is the crack surface roughness, and is the empirical coefficient.

[0217] Based on the mechanical equilibrium conditions of the fracture surface and the induced stress matrix, the matrix equations of the supported fractures and unsupported fractures in the first fracturing stage can be established:

[0218] (Formula 18)

[0219] ;(Formula 19)

[0220] In the formula is the formation closure stress; is the influence coefficient matrix, which can be obtained by (Formula 2); is the residual width of the fracture supported by the first fracturing stage; is the residual width of the unsupported crack in the first fracturing stage; the residual width of the crack can be obtained by iteratively solving the above nonlinear equations (Formula 18-Formula 19) .

[0221] In the process of three-dimensional well pattern fracturing, due to the existence of residual crack width in the first fracturing section, it will cause stress interference to the cracks in the subsequent fracturing section. According to the principle of superposition, the fluid pressure balance equation in the fracture can be re-established:

[0222] (Formula 20)

[0223] Therefore, for hydraulic fractures disturbed by the first fracturing stage, the fluid pressure in the fracture is calculated by replacing (Formula 7) with (Formula 20).

[0224] S205: Determine whether the crack has expanded, and update the length of the crack according to the crack expansion.

[0225] For the expansion of non-planar hydraulic fractures, the method for judging whether hydraulic fractures have expanded is as follows based on the linear elastic fracture mechanics criterion:

[0226] (Formula 13)

[0227] Among them, K Ic is the fracture toughness, w is the critical crack width, d is the distance from the crack tip, and E is the Young's modulus.

[0228] Compare the actual crack width of the tip unit with the critical crack width. If the actual crack width of the tip unit is greater than the critical crack width, the crack expands and continues to activate a circle of grid units outward, that is, the crack length plus the length of one crack grid unit; if the actual crack width of the tip unit is less than the critical crack width, the crack does not expand.

[0229] If the crack propagates, the I-mode stress intensity factor K of the crack tip element is calculated. I and type II stress intensity factor K II Calculated based on the unit displacement discontinuity:

[0230] (Formula 14)

[0231] According to the maximum circumferential stress criterion, the crack extension direction is determined:

[0232] (Formula 15)

[0233] Among them, K I Mode I stress intensity factor of crack tip element, K II Mode II stress intensity factor of the crack tip element, It is the angle between the unit to be activated and the current tip unit, also called the crack extension direction. The purpose of this is not only to gradually activate the cracks and expand the cracks during the calculation process, but also to adjust the crack extension direction in real time. Dn is the normal displacement, the same as D1; ​​Ds is the tangential displacement, the same as D3.

[0234] S206. In each time step, a forward modeling simulation of the distributed optical fiber monitoring signal of the adjacent wells is performed to obtain a forward modeling result in each time step.

[0235] Among them, the method for obtaining the forward simulation results at each time step is:

[0236] The induced displacement of non-planar hydraulic fracture units can be calculated by the displacement discontinuity method, which is expressed as:

[0237] (Formula 21)

[0238] in, is the induced displacement of the optical fiber axis caused by crack unit i, ,

[0239] , and is the derivative of the kernel function in (Equation 4), v is the Poisson's ratio, and G is the shear modulus.

[0240] (Formula 22)

[0241] (Formula 23)

[0242] (Formula 24)

[0243] in, and are the local coordinates of the grid cells.

[0244] Considering that the number of hydraulic fracture grid units is N, the induced displacement of each unit on the optical fiber monitoring point can be calculated by the above formula, and then the total displacement of the optical fiber monitoring point can be obtained by the superposition principle.

[0245] (Formula 25)

[0246] Wherein, is the axial displacement of the monitoring unit j on the optical fiber monitoring well. In actual optical fiber strain monitoring of adjacent wells, the average strain disturbance of the optical fiber over a certain measuring distance is obtained. The optical fiber strain value can be simulated and calculated based on the induced total displacement of the optical fiber monitoring point:

[0247] (Formula 26)

[0248] in, is the optical fiber strain value of unit j, and L is the measurement distance. Then the strain rate is expressed according to the degree of strain per unit time:

[0249] (Formula 27);

[0250] According to this method, the induced displacement, strain and strain rate of each optical fiber measurement point are calculated. Similarly, for three-dimensional well network fracturing, the signals on adjacent optical fiber monitoring wells will be affected by the first fracture. According to the real-time simulation results of the first fracture width, the induced displacement field, strain and strain rate results of the optical fiber monitoring well are superimposed and calculated.

[0251] S207. When the amount of fracturing fluid injected into the well reaches a preset amount, the simulation is stopped and the results are output, wherein the output results include the morphology of the fracturing cracks, the induced displacement of the adjacent optical fiber monitoring wells, the strain value and the strain rate.

[0252] S208: Determine whether the error between the output result and the actual distributed optical fiber strain monitoring signal of the adjacent well is less than a preset error threshold.

[0253] S209A: If the error between the output result and the actual distributed optical fiber strain monitoring signal of the adjacent wells on site is less than a preset error threshold, the morphology of the fracturing crack is interpreted.

[0254] S209B. If the error between the output result and the actual distributed optical fiber strain monitoring signal of the adjacent wells on site is greater than the preset error threshold, the geological parameters are adjusted, and hydraulic fracturing and optical fiber strain monitoring evolution simulation is performed until the error is less than the preset error threshold.

[0255] Among them, the error acquisition method between the output result and the actual distributed optical fiber strain monitoring signal of the adjacent wells on site is:

[0256] The optical fiber strain rate simulated by the numerical model is compared with the optical fiber strain rate actually monitored on site to obtain the optical fiber strain rate error at time t. :

[0257] ;

[0258] Where is the strain rate of the jth distributed optical fiber strain monitoring point obtained by numerical simulation, and is the optical fiber strain rate obtained by actual on-site monitoring. The total error is obtained by integrating the optical fiber strain rate error within a given pumping time T:

[0259] ;

[0260] Another method for interpreting fracture morphology of three-dimensional well network fracturing based on distributed optical fiber monitoring provided in an embodiment of the present application can effectively improve the ability to finely monitor and interpret the expansion morphology of hydraulic fractures during three-dimensional well network fracturing, thereby providing a reliable basis for understanding the effect of fracturing transformation and real-time adjustment of construction technology.

[0261] Figure 3 A schematic diagram of the expansion morphology of the three-dimensional well pattern fracturing cracks provided in the embodiment of the present application is shown in FIG. Figure 3 As shown, the position of the crack in the spatial coordinate system can be represented by the corresponding numerical values ​​of the xyz axis, the width of the crack can be represented by the color in Fracture Width, and the crack width of the crack at any coordinate in the spatial coordinate system can be confirmed by color comparison. The crack length is the difference between the y coordinate of the beginning of the crack and the y coordinate of the end of the crack.

[0262] Figure 4 The embodiment of the present application provides a schematic diagram of the evolution of optical fiber strain signals induced in adjacent wells during the expansion of fractures in a three-dimensional well pattern, such as Figure 4As shown in the figure, the structural components of the fiber optic detection well from the inside to the outside are: cement ring, optical fiber, rock. The fracture initiation in stage 1, the approach of the fracture in stage 2, the intersection of the fracture in stage 3, and the crossing of the fracture in stage 4 of the fracturing well 1 will cause the fiber to stretch, affecting the strain value of the fiber optic signal, while the closure of the fracture in stage 5 will cause the fiber to compress, affecting the strain value of the fiber optic signal. As the hydraulic fracture in the fracturing well gradually extends to the adjacent monitoring well, the distributed optical fiber is first subjected to tensile stress, and the closer the hydraulic fracture is to the monitoring well, the stronger the tensile stress is (i.e., stage 1 to stage 2). When the hydraulic fracture intersects with the adjacent monitoring well (i.e., stage 3), the tensile stress on the distributed optical fiber reaches the maximum value, and then immediately turns into compressive stress on both sides of the intersection of the hydraulic fracture, and the optical fiber monitoring unit at the intersection is still tensile stress. Finally, during the crack closure process, the compressive stress and tensile stress intensity are weakened until the final strain value is obtained.

[0263] Figure 5 The fracture propagation simulation results of a fracture stage with only one perforation cluster in the embodiment of the present application are provided. Figure 5 As shown, the figure includes a fiber optic detection well, a fracturing well, and a crack. The fracturing well includes a fracturing section, and the fracturing section includes a crack of a perforation cluster. By comparing the color of the crack with the color in the adjacent strip, the corresponding crack width value can be obtained.

[0264] Fig. 6A The displacement field induced by a cluster of crack extensions in adjacent optical fiber monitoring wells provided in the embodiment of the present application, Figure 6B The optical fiber strain (value) signal induced by a cluster of crack extensions in adjacent optical fiber monitoring wells provided in the embodiment of the present application, Figure 6C The present application embodiment provides a strain rate signal induced by a cluster of crack extensions in adjacent optical fiber monitoring wells. Fig. 6A It is characterized that before the hydraulic fracture intersects with the adjacent optical fiber monitoring well, the induced displacement in the distributed optical fiber gradually increases with time. When the hydraulic fracture intersects with the monitoring well, there are obvious opposite displacements on both sides of the hydraulic fracture. Figure 6B It is characterized that before the hydraulic fracture intersects with the adjacent optical fiber monitoring well, the strain (value) and strain signal of the distributed optical fiber gradually increase with time. When the hydraulic fracture intersects with the monitoring well, the distributed optical fiber strain signal converges into a strip. Figure 6C It is characterized that before the hydraulic fracture intersects with the adjacent optical fiber monitoring well, the strain and strain rate signals of the distributed optical fiber gradually increase with time. After the hydraulic fracture intersects with the monitoring well, the distributed optical fiber strain rate signal converges into a strip with time.

[0265] Figure 7The simulation result of fracture propagation with multiple perforation clusters in a fracturing section provided in the embodiment of the present application. The figure includes a fiber optic detection well, a fracturing well, and a fracture. The fracturing well includes a fracturing section, and the fracturing section includes fractures with multiple perforation clusters. The color of the fracture is compared with the color of the adjacent strip indicating the width of the fracture to obtain the corresponding fracture width.

[0266] Fig. 8A The distributed optical fiber strain simulation results induced in adjacent optical fiber monitoring wells when multiple clusters of cracks are synchronously extended are provided in the embodiment of the present application. The information such as the extension speed and orientation of multiple cracks can be obtained through the optical fiber strain signal. Figure 8B The simulation results of the distributed optical fiber strain rate signal induced in adjacent optical fiber monitoring wells when multiple clusters of fractures are synchronously extended are provided in the embodiment of the present application. The optical fiber strain rate signal can be used to identify the expansion speed, orientation and other information of multiple fractures. After obtaining the distributed optical fiber strain signal actually monitored on site, forward simulation can be carried out according to the method of the present application to obtain the distributed optical fiber strain signal of simulated monitoring. By comparing the distributed optical fiber strain signal actually monitored on site with the distributed optical fiber strain signal of simulated monitoring, the corresponding hydraulic fracture expansion morphology can be obtained.

[0267] Fig. 9 This is a structural example diagram of a three-dimensional well network fracturing crack morphology interpretation device based on distributed optical fiber monitoring provided in an embodiment of the present application. Fig. 9 As shown, the three-dimensional well network fracturing crack morphology interpretation device 90 based on distributed optical fiber monitoring includes: an acquisition module 901, a first acquisition module 902, a second acquisition module 909, and a determination module 904. Among them:

[0268] The acquisition module 901 is used to acquire geological parameters, fracturing well construction parameters, adjacent monitoring well parameters, and actual optical fiber strain rate; wherein the geological parameters represent geological characteristics and geological conditions; the fracturing well construction parameters represent the construction requirements for fracturing a horizontal fracturing well; the adjacent monitoring well parameters represent the well parameters of the optical fiber monitoring wells in a preset area outside the three-dimensional well network, the three-dimensional well network includes multiple horizontal fracturing wells, and the optical fiber monitoring wells are used to monitor the expansion of fracturing cracks in the horizontal fracturing wells; the actual optical fiber strain rate represents the rate at which the actually measured optical fiber length changes over time when subjected to external stress;

[0269] The first obtaining module 902 is used to obtain simulated fracture morphology information according to geological parameters, fracturing well construction parameters, and adjacent monitoring well parameters; wherein the simulated fracture morphology information includes at least one of simulated fracture width, fracture length, and fluid pressure in the fracture;

[0270] The second obtaining module 909 is used to obtain a simulated optical fiber strain rate according to the simulated fracture morphology information, geological parameters and adjacent monitoring well parameters; wherein the simulated optical fiber strain rate represents the rate at which the simulated optical fiber length changes with time under different time period lengths;

[0271] The determination module 904 is used to determine whether the simulated fracture morphology information is the actual fracture morphology information of the horizontal fracturing well according to the simulated optical fiber strain rate and the actual optical fiber strain rate; wherein the actual fracture morphology information includes at least one of the actual fracture width, fracture length, and fluid pressure in the fracture.

[0272] In one example, the first obtaining module 902 includes:

[0273] A first determination unit is used to determine an initial time period length according to a preset initial fracture length; wherein the time period length represents the injection of liquid into the horizontal fracturing well within the range of the time period length;

[0274] The second determination unit is used to determine the crack width, crack length, and fluid pressure in the crack corresponding to the next time period length according to the initial time period length, the preset initial crack width, and the fracturing well construction parameters, and continue to determine the new next time period length according to the crack length corresponding to the next time period length;

[0275] The third determination unit is used to obtain the crack width, crack length, and fluid pressure in the crack corresponding to the last time period until the total volume of the liquid injected in all the time periods is the preset volume, so as to simulate the crack morphology information.

[0276] In one example, the third determining unit is specifically configured to:

[0277] Determine the fracture displacement information corresponding to each time period length according to geological parameters, parameters of adjacent monitoring wells, and simulated fracture morphology information corresponding to each time period length; wherein the fracture displacement information represents the displacement of the hydraulic fracture within the time period length;

[0278] According to the fracture displacement information corresponding to the length of each time period and the parameters of the adjacent monitoring wells, the simulated optical fiber strain rate corresponding to the length of each time period is obtained.

[0279] In one example, the third determining unit is specifically configured to:

[0280] According to the crack displacement information corresponding to the length of each time period, the optical fiber strain value corresponding to the length of each time period is determined; wherein the optical fiber strain value represents the deformation of the optical fiber under stress measured by the optical fiber sensing technology;

[0281] According to the optical fiber strain value corresponding to each time period and the parameters of the adjacent monitoring wells, the simulated optical fiber strain rate corresponding to each time period is obtained.

[0282] In one example, the determination module 904 includes:

[0283] a fourth determining unit, configured to determine error information between each simulated optical fiber strain rate and an actual optical fiber strain rate;

[0284] The fifth determination unit is used to determine whether the simulated fracture morphology information is the actual fracture morphology information of the horizontal fracturing well according to each error information and a preset error threshold.

[0285] In one embodiment, the fifth determining unit is specifically configured to:

[0286] Performing integration processing on each error information, and comparing the value obtained after the integration processing with a preset error value threshold;

[0287] If the value obtained after the integration process is less than the preset error threshold, the simulated fracture morphology information is determined to be the actual fracture morphology information of the horizontal fracturing well;

[0288] If the value obtained after the integral processing is greater than the preset error threshold, the geological parameters are adjusted and new simulated fracture morphology information is obtained based on the adjusted geological parameters, fracturing well construction parameters, and adjacent monitoring well parameters until the value obtained after the integral processing is less than the preset error threshold.

[0289] In one example, the first obtaining module 902 includes:

[0290] A sixth determination unit is used to determine the serial number of the fracturing section of the fracturing crack in the horizontal fracturing well; wherein the fracturing section represents a section in the wellbore of the horizontal fracturing well;

[0291] A seventh determination unit is used to determine the fluid pressure in the fracture of the next time period length of the time period length according to the fracture width corresponding to the time period length and the fracturing well construction parameters if the serial number of the fracturing stage is the preset first serial number;

[0292] The acquisition unit is used to acquire the proppant concentration of the fracturing stage before the fracturing stage if the sequence number of the fracturing stage is the preset second sequence number, and determine the fluid pressure in the fracture of the next time period length of the time period length according to the proppant concentration, the crack width corresponding to the time period length, and the fracturing well construction parameters; wherein the proppant concentration represents the concentration of the proppant in the fracturing fluid.

[0293] Fig.10 This is a schematic diagram of the structure of an electronic device provided in an embodiment of the present application. Fig.10 As shown, the electronic device 100 includes:

[0294] The electronic device 100 may include a processor 1001 with one or more processing cores, a memory 1002 with one or more computer-readable storage media, a communication component 1003 and other components. The processor 1001, the memory 1002 and the communication component 1003 are connected via a bus 1004.

[0295] In the specific implementation process, at least one processor 1001 executes the computer execution instructions stored in the memory 1002, so that at least one processor 1001 executes the above-mentioned three-dimensional well network fracturing fracture morphology interpretation method based on distributed optical fiber monitoring.

[0296] The specific implementation process of the processor 1001 can be found in the above method embodiment, and its implementation principle and technical effect are similar, so this embodiment will not be repeated here.

[0297] In the above Fig.10 In the illustrated embodiment, it should be understood that the processor may be a central processing unit (CPU), or other general-purpose processors, digital signal processors (DSP), application-specific integrated circuits (ASIC), etc. A general-purpose processor may be a microprocessor or any conventional processor, etc. The steps of the method disclosed in the invention may be directly implemented as being executed by a hardware processor, or may be executed by a combination of hardware and software modules in the processor.

[0298] The memory may include a high-speed memory (Random Access Memory, RAM), and may also include a non-volatile memory (NVM), such as at least one disk storage.

[0299] The bus can be an Industry Standard Architecture (ISA) bus, a Peripheral Component Interconnect (PCI) bus, or an Extended Industry Standard Architecture (EISA) bus, etc. The bus can be divided into an address bus, a data bus, a control bus, etc. For ease of representation, the bus in the drawings of this application is not limited to only one bus or one type of bus.

[0300] In some embodiments, a computer program product is also proposed, including a computer program or instructions, which, when executed by a processor, implements the steps in any of the above-mentioned methods for interpreting fracture morphology of three-dimensional well network fracturing based on distributed optical fiber monitoring.

[0301] The specific implementation of the above operations can be found in the previous embodiments, which will not be described in detail here.

[0302] A person of ordinary skill in the art will appreciate that all or part of the steps in the various methods of the above embodiments may be completed by instructions, or by controlling related hardware through instructions. The instructions may be stored in a computer-readable storage medium and loaded and executed by a processor.

[0303] To this end, an embodiment of the present application provides a computer-readable storage medium, which stores multiple instructions, which can be loaded by a processor to execute the steps in any one of the methods for interpreting fracture morphology of three-dimensional well network fracturing based on distributed optical fiber monitoring provided in the embodiments of the present application.

[0304] The storage medium may include: a read-only memory (ROM), a random access memory (RAM), a magnetic disk or an optical disk, etc.

[0305] According to one aspect of the present application, a computer program product or a computer program is provided. The computer program product or the computer program comprises computer instructions stored in a computer-readable storage medium.

[0306] Since the instructions stored in the storage medium can execute the steps in any one of the methods for interpreting the morphology of three-dimensional well network fracturing cracks based on distributed optical fiber monitoring provided in the embodiments of the present application, the beneficial effects that can be achieved by any one of the methods for interpreting the morphology of three-dimensional well network fracturing cracks based on distributed optical fiber monitoring provided in the embodiments of the present application can be achieved. For details, please refer to the previous embodiments and will not be repeated here.

[0307] Those skilled in the art will readily appreciate other embodiments of the present application after considering the specification and practicing the invention disclosed herein. The present application is intended to cover any modification, use or adaptation of the present application, which follows the general principles of the present application and includes common knowledge or customary techniques in the art that are not disclosed in the present application. The specification and examples are intended to be exemplary only, and the true scope and spirit of the present application are indicated by the following claims.

[0308] It should be understood that the present application is not limited to the precise structures that have been described above and shown in the drawings, and that various modifications and changes may be made without departing from the scope thereof. The scope of the present application is limited only by the appended claims.

Claims

1. A method for interpreting fracture morphology of three-dimensional well pattern fracturing based on distributed optical fiber monitoring, characterized in that: The method comprises: Obtaining geological parameters, fracturing well construction parameters, adjacent monitoring well parameters, and actual optical fiber strain rate; wherein the geological parameters represent geological characteristics and geological conditions; the fracturing well construction parameters represent construction requirements for fracturing horizontal fracturing wells; the adjacent monitoring well parameters represent well parameters of optical fiber monitoring wells within a preset area outside a three-dimensional well network, wherein the three-dimensional well network includes a plurality of horizontal fracturing wells, and the optical fiber monitoring wells are used to monitor the expansion of cracks in the horizontal fracturing wells; and the actual optical fiber strain rate represents the rate at which the actually measured optical fiber length changes over time when subjected to external stress; According to the geological parameters, the fracturing well construction parameters, and the adjacent monitoring well parameters, simulated fracture morphology information is obtained; wherein the simulated fracture morphology information includes at least one of the simulated fracture width, fracture length, and fluid pressure in the fracture; According to the simulated fracture morphology information, the geological parameters and the adjacent monitoring well parameters, a simulated optical fiber strain rate is obtained; wherein the simulated optical fiber strain rate represents the rate at which the optical fiber length obtained by simulation changes with time under different time period lengths; Determining whether the simulated fracture morphology information is actual fracture morphology information of a horizontal fracturing well according to the simulated optical fiber strain rate and the actual optical fiber strain rate; wherein the actual fracture morphology information includes at least one of an actual fracture width, a fracture length, and a fluid pressure in the fracture; The method of obtaining simulated fracture morphology information according to the geological parameters, the fracturing well construction parameters, and the adjacent monitoring well parameters includes: Determine the initial time period length according to the preset initial crack length; wherein the time period length represents the injection of liquid into the horizontal fracturing well within the range of the time period length; Determine the crack width, crack length, and fluid pressure in the crack corresponding to the next time period length according to the initial time period length, the preset initial crack width, and the fracturing well construction parameters, and continue to determine a new next time period length according to the crack length corresponding to the next time period length; Until the total volume of liquid injected in all the time periods is determined to be the preset volume, the crack width, crack length, and fluid pressure in the crack corresponding to the last time period are obtained, which are the simulated crack morphology information; The step of obtaining a simulated optical fiber strain rate according to the simulated fracture morphology information, the geological parameters and the adjacent monitoring well parameters includes: Determine the fracture displacement information corresponding to each time period length according to the geological parameters, the adjacent monitoring well parameters, and the simulated fracture morphology information corresponding to each time period length; wherein the fracture displacement information represents the displacement of the hydraulic fracture within the time period length; According to the fracture displacement information corresponding to the length of each time period and the adjacent monitoring well parameters, the simulated optical fiber strain rate corresponding to the length of each time period is obtained.

2. The method according to claim 1, characterized in that The method of obtaining the simulated optical fiber strain rate corresponding to the length of each time period according to the fracture displacement information corresponding to the length of each time period and the adjacent monitoring well parameters includes: According to the crack displacement information corresponding to the length of each time period, determine the optical fiber strain value corresponding to the length of each time period; wherein the optical fiber strain value represents the deformation of the optical fiber under stress measured by the optical fiber sensing technology; According to the optical fiber strain value corresponding to each time period length and the adjacent monitoring well parameters, the simulated optical fiber strain rate corresponding to each time period length is obtained.

3. The method according to claim 1, characterized in that The step of determining whether the simulated fracture morphology information is actual fracture morphology information of a horizontal fracturing well according to the simulated optical fiber strain rate and the actual optical fiber strain rate comprises: Determining error information between each of the simulated optical fiber strain rates and the actual optical fiber strain rate; According to each of the error information and a preset error threshold, it is determined whether the simulated fracture morphology information is actual fracture morphology information of the horizontal fracturing well.

4. The method according to claim 3, characterized in that Determining whether the simulated fracture morphology information is actual fracture morphology information of the horizontal fracturing well according to each of the error information and a preset error threshold comprises: Performing integration processing on each of the error information, and comparing the value obtained after the integration processing with a preset error value threshold; If the value obtained after the integral processing is less than a preset error threshold, the simulated fracture morphology information is determined to be actual fracture morphology information of the horizontal fracturing well; If the value obtained after the integral processing is greater than the preset error threshold, the geological parameters are adjusted and new simulated fracture morphology information is obtained based on the adjusted geological parameters, the fracturing well construction parameters, and the adjacent monitoring well parameters, until the value obtained after the integral processing is less than the preset error threshold.

5. The method according to claim 1, characterized in that Also includes: Determining the serial number of the fracturing section of the fracturing crack in the horizontal fracturing well; wherein the fracturing section represents a section in the wellbore of the horizontal fracturing well; If the sequence number of the fracturing stage is the preset first sequence number, then for each time period length, according to the crack width corresponding to the time period length and the fracturing well construction parameters, determine the fluid pressure in the crack of the next time period length of the time period length; If the serial number of the fracturing stage is a preset second serial number, the proppant concentration of the fracturing stage before the fracturing stage is obtained, and the fluid pressure in the fracture of the next time period of the time period is determined according to the proppant concentration, the crack width corresponding to the time period length, and the fracturing well construction parameters; wherein the proppant concentration represents the concentration of the proppant in the fracturing fluid.

6. A three-dimensional well network fracturing crack morphology interpretation device based on distributed optical fiber monitoring, characterized in that: Used to implement the method according to any one of claims 1 to 5, comprising: An acquisition module is used to acquire geological parameters, fracturing well construction parameters, adjacent monitoring well parameters, and actual optical fiber strain rate; wherein the geological parameters represent geological characteristics and geological conditions; the fracturing well construction parameters represent construction requirements for fracturing horizontal fracturing wells; the adjacent monitoring well parameters represent well parameters of optical fiber monitoring wells within a preset area outside a three-dimensional well network, wherein the three-dimensional well network includes a plurality of horizontal fracturing wells, and the optical fiber monitoring wells are used to monitor the expansion of fracturing cracks in the horizontal fracturing wells; and the actual optical fiber strain rate represents the rate at which the actually measured optical fiber length changes over time when subjected to external stress; A first obtaining module is used to obtain simulated fracture morphology information according to the geological parameters, the fracturing well construction parameters, and the adjacent monitoring well parameters; wherein the simulated fracture morphology information includes at least one of the simulated fracture width, fracture length, and fluid pressure in the fracture; The second obtaining module is used to obtain a simulated optical fiber strain rate according to the simulated fracture morphology information, the geological parameters and the adjacent monitoring well parameters; wherein the simulated optical fiber strain rate represents the rate at which the optical fiber length obtained by simulation changes with time under different time period lengths; A determination module is used to determine whether the simulated fracture morphology information is actual fracture morphology information of a horizontal fracturing well according to the simulated optical fiber strain rate and the actual optical fiber strain rate; wherein the actual fracture morphology information includes at least one of an actual fracture width, a fracture length, and a fluid pressure in the fracture.

7. An electronic device, characterized in that: include: A processor, and a memory communicatively connected to the processor; The memory stores computer-executable instructions; The processor executes the computer-executable instructions stored in the memory to implement the method according to any one of claims 1 to 5.

8. A computer-readable storage medium, characterized in that: The computer-readable storage medium stores computer-executable instructions, which are used to implement the method according to any one of claims 1 to 5 when executed by a processor.

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