Method and device for determining horizontal well fracturing hole cluster spacing

Abstract

The invention discloses a method and device for determining the distance between fracturing hole clusters of a horizontal well and a machine readable storage medium, and relates to the technical field of oil and gas field development. The method comprises the following steps: determining a stress shadow of a fracturing hole cluster of a target fracturing section according to a logging curve and a net pressure fracture fitting result; determining the influence distance of the stress shadow of the fracturing hole cluster according to the stress shadow; according to the logging curve, the rock sample compression experiment data, the fluid sample compression experiment data and the fluid viscosity experiment data, determining a fracture interval corresponding to a mass transfer distance of oil gas flowing from a matrix to a fracture of the target fracturing section; and according to the minimum value of the influence distance and the crack distance, the fracturing hole cluster distance is determined. According to the method, the cluster spacing of the adjacent fracturing hole clusters can be reasonably determined.

Description

Technical Field

[0001] The present application relates to the technical field of oil and gas field development, and in particular to a method, device and machine-readable storage medium for determining the spacing between fracturing hole clusters in a horizontal well. Background Art

[0002] Multi-stage fracturing has become a key technology for the development of unconventional oil reservoirs. Among them, the horizontal well cluster perforation spacing is a key parameter in the design of volume fracturing in unconventional oil and gas reservoirs, and the size of the cluster spacing has an important impact on the fracturing transformation of unconventional oil and gas reservoirs. Reasonable optimization design of horizontal well fracturing cluster spacing has important theoretical value and practical significance in the mine, and can effectively improve the blindness of horizontal well segmented perforation distribution. Therefore, determining the optimal fracturing perforation cluster spacing has always been a challenge faced by the mine. This problem is particularly critical in the completion design of tight reservoirs. For horizontal wells with different lithologies in different regions, the methods of cluster spacing optimization design are also different. Usually, the number and position of cluster spacing are often optimized through numerical simulation, but this is a time-consuming and subjective process, and the resulting method often fails to fully consider the characteristics of the reservoir. Summary of the invention

[0003] The purpose of the embodiments of the present application is to provide a method, device and machine-readable storage medium for determining the spacing between fracturing hole clusters in horizontal wells, so as to solve the technical problem that the prior art does not fully consider the reservoir characteristics and cannot reasonably determine the spacing between fracturing hole clusters.

[0004] In order to achieve the above-mentioned object, the first aspect of the present application provides a method for determining the spacing of fracturing hole clusters in a horizontal well, comprising:

[0005] Obtaining a well logging curve of a target fracturing section, a net pressure fracture fitting result of the target fracturing section, rock sample compression experimental data of the target fracturing section, and fluid sample compression experimental data and fluid viscosity experimental data of the fluid sample of the target fracturing section;

[0006] Determine the stress shadow of the fracturing hole cluster in the target fracturing section based on the well logging curve and the net pressure fracture fitting result;

[0007] Determine the influence distance of the stress shadow of the fracturing hole cluster according to the stress shadow;

[0008] Determine the fracture spacing corresponding to the mass transfer distance of oil and gas flowing from the matrix to the fractures in the target fracturing section based on the well logging curve, rock sample compression test data, fluid sample compression test data, and fluid viscosity test data;

[0009] The distance between the fracture clusters is determined based on the minimum value between the influence distance and the fracture distance.

[0010] In an embodiment of the present application, the stress shadow of the fracturing hole cluster of the target fracturing section is determined according to the well logging curve and the net pressure crack fitting result, including: according to the well logging curve and the net pressure crack fitting result, the stress shadow of the target fracturing section is determined by the analytical expression of the induced stress field generated by the constant height two-dimensional vertical cracks of the isotropic homogeneous linear elastic material; or, according to the well logging curve and the net pressure crack fitting result, the stress shadow of the target fracturing section is determined by the Boucinnet equation.

[0011] In an embodiment of the present application, according to the logging curve and the net pressure crack fitting result, the stress shadow of the target fracturing section is determined by the analytical expression of the induced stress field generated by the constant height two-dimensional vertical crack of the isotropic homogeneous linear elastic material, including: determining the average Young's modulus and the average Poisson's ratio of the target fracturing section according to the logging curve, and determining the average fracture width and the average fracture height of the fracturing section according to the net pressure crack fitting result; according to the average Young's modulus, the average Poisson's ratio, the average fracture width and the average fracture height of the fracturing crack, the stress shadow is determined by the analytical expression of the induced stress field generated by the constant height two-dimensional vertical crack of the isotropic homogeneous linear elastic material.

[0012] In an embodiment of the present application, the stress shadow of the target fracturing section is determined according to the well logging curve and the net pressure crack fitting result through the Boucinnet equation, including: determining the average Young's modulus of the target fracturing section according to the well logging curve, and determining the average fracture width of the fracturing section according to the net pressure crack fitting result; according to the average Young's modulus and the average fracture width of the fracturing crack, the stress shadow of the target fracturing section is determined by coupling the shear boundary condition and the Boucinnet equation under the pore-elastic effect.

[0013] In an embodiment of the present application, the fracture spacing corresponding to the mass transfer distance of oil and gas flowing from the matrix to the fractures in the target fracturing section is determined according to the logging curve, rock sample compression experimental data, fluid sample compression experimental data and fluid viscosity experimental data, including: determining the permeability and porosity in the fracturing section according to the logging curve, determining the rock compression coefficient of the rock sample according to the rock sample compression experimental data, determining the fluid compression coefficient of the fluid sample according to the compression experimental data of the fluid sample, and determining the fluid viscosity of the fluid sample according to the fluid viscosity experimental data; based on the one-dimensional diffusion equation of linear flow, the fracture spacing corresponding to the mass transfer distance is determined according to the permeability, porosity, rock compression coefficient, fluid compression coefficient and fluid viscosity.

[0014] In an embodiment of the present application, the stress shadow of the fracturing hole cluster is the stress shadow when the fracturing hole cluster has a preset number of open fracturing holes; the fracture spacing corresponding to the mass transfer distance of oil and gas flowing from the matrix to the fracture is the fracture spacing corresponding to the mass transfer distance of oil and gas flowing from the matrix to the fracture when the fracturing hole cluster has a preset number of open fracturing holes; the method also includes: obtaining the effective number of openings of the fracturing hole cluster of the target fracturing section; determining the average effective opening rate of the fracturing hole cluster of the target fracturing section according to the ratio of the effective number of openings to the preset number of fracturing holes; determining the fracturing hole cluster spacing according to the minimum value of the influencing distance and the fracture spacing, including: determining the fracturing hole cluster spacing according to the product of the minimum value and the average effective opening rate.

[0015] In an embodiment of the present application, obtaining the effective number of openings of the fracturing hole cluster of the target fracturing section includes: determining the effective number of openings of the fracturing hole cluster of the target fracturing section according to a logging curve of the target fracturing section.

[0016] In an embodiment of the present application, based on the one-dimensional diffusion equation of linear flow, the fracture spacing corresponding to the mass transfer distance is determined according to the permeability, porosity, rock compressibility, fluid compressibility and fluid viscosity, including: based on the one-dimensional diffusion equation of linear flow, according to the permeability, porosity, rock compressibility, fluid compressibility and fluid viscosity, determining the relationship between the production life and mass transfer distance of the production wells of the target fracturing section; determining the fracture spacing of the production wells of the target fracturing section under the target production life according to the relationship between the production life and fracture spacing of the target fracturing section.

[0017] A second aspect of the present application provides a device for determining the spacing between fracturing hole clusters in a horizontal well, comprising:

[0018] A memory is configured to store instructions; and a processor is configured to call the instructions from the memory and implement the method for determining the spacing between fracturing hole clusters in a horizontal well according to any of the above embodiments when executing the instructions.

[0019] A third aspect of the present application provides a machine-readable storage medium having instructions stored thereon, the instructions being used to enable a machine to execute a method for determining the spacing between fracturing hole clusters in a horizontal well provided according to any one of the above embodiments.

[0020] Through the above technical scheme, the characteristics of reservoir seepage mechanics and solid mechanics can be fully considered to determine the stress shadow and mass transfer distance that can be generated by the fluid released by the fracturing hole cluster for fracturing the soil at the target fracturing section; and the minimum value of the stress shadow and the mass transfer distance is selected to determine the fracturing hole cluster spacing, so that the horizontal wells in the target fracturing section can fully utilize the reservoir and keep the adjacent fracturing hole clusters of the horizontal wells at a reasonable cluster spacing.

[0021] Other features and advantages of the embodiments of the present application will be described in detail in the subsequent specific implementation section. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] The accompanying drawings are used to provide a further understanding of the embodiments of the present application and constitute a part of the specification. Together with the following specific implementations, they are used to explain the embodiments of the present application, but do not constitute a limitation on the embodiments of the present application. In the accompanying drawings:

[0023] Figure 1 A schematic diagram of a process for determining the spacing between fracturing hole clusters in a horizontal well according to an embodiment of the present application is schematically shown;

[0024] Figure 2 A schematic diagram of a process for determining the spacing of fracturing hole clusters in a horizontal well based on the effective opening rate according to an embodiment of the present application is shown;

[0025] Figure 3 A schematic diagram of the relationship between production years and mass transfer distance of the linear flow one-dimensional diffusion equation is shown;

[0026] Figure 4 The schematic diagram of the relationship between the stress shadow influence distance and the induced stress of the analytical expression of the induced stress field generated by a constant-height two-dimensional vertical crack of an isotropic homogeneous linear elastic material is shown;

[0027] Figure 5 The diagram schematically shows the relationship between the distance from the fracture surface and the induced stress of the Boucinnet equation under the coupled shear boundary condition and the pore-elastic effect. DETAILED DESCRIPTION

[0028] In order to make the purpose, technical scheme and advantages of the embodiments of the present application clearer, the technical scheme in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. It should be understood that the specific implementation methods described herein are only used to illustrate and explain the embodiments of the present application, and are not used to limit the embodiments of the present application. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of this application.

[0029] It should be noted that the acquisition, transmission, storage, use, and processing of data in the technical solution of this application are in compliance with the relevant provisions of national laws and regulations. In the embodiments of this application, some existing solutions in the industry such as certain software, components, and models may be mentioned, which should be considered as exemplary. Their purpose is only to illustrate the feasibility of implementing the technical solution of this application, but it does not mean that the applicant has or will necessarily use the solution.

[0030] It should be noted that if the embodiments of the present application involve directional indications (such as up, down, left, right, front, back...), the directional indications are only used to explain the relative position relationship, movement status, etc. between the components under a certain specific posture (as shown in the accompanying drawings). If the specific posture changes, the directional indication will also change accordingly.

[0031] In addition, if there are descriptions involving "first", "second", etc. in the embodiments of the present application, the descriptions of "first", "second", etc. are only used for descriptive purposes and cannot be understood as indicating or suggesting their relative importance or implicitly indicating the number of technical features indicated. Therefore, the features defined as "first" and "second" may explicitly or implicitly include at least one of the features. In addition, the technical solutions between the various embodiments can be combined with each other, but they must be based on the ability of ordinary technicians in the field to implement them. When the combination of technical solutions is contradictory or cannot be implemented, it should be deemed that such combination of technical solutions does not exist and is not within the scope of protection required by this application.

[0032] In the process of horizontal well fracturing and exploitation in oil and gas fields, the horizontal well perforation cluster is used to release fluids such as water into the surrounding soil to form cracks in the soil near the horizontal well, thereby realizing the exploitation of oil and gas. In the actual operation of the perforation cluster, if the cluster spacing of the perforation cluster is too small, it will cause the transformation areas between the main fractures of the clusters to overlap and affect the competition between the fractures, thus reducing the efficiency of the fracturing transformation; too large a cluster spacing will produce untransformed areas between the main fractures, affecting the degree of reservoir utilization. Therefore, based on the consideration of soil properties, the inventor of the present application proposed a method for determining the spacing of horizontal well fracturing hole clusters based on the soil fracture conductivity characteristics.

[0033] Figure 1 The following schematically shows a flow chart of a method for determining the spacing between fracturing holes in a horizontal well according to an embodiment of the present application. Figure 1 As shown, the embodiment of the present application provides a method for determining the spacing between fracturing hole clusters in a horizontal well, which may include the following steps:

[0034] S102, obtaining a well logging curve of a target fracturing section, a net pressure fracture fitting result of the target fracturing section, rock sample compression experimental data of the target fracturing section, and fluid sample compression experimental data and fluid viscosity experimental data of the fluid sample of the target fracturing section;

[0035] S104, determining the stress shadow of the fracturing hole cluster of the target fracturing section according to the well logging curve and the net pressure fracture fitting result;

[0036] S106, determining the influence distance of the stress shadow of the fracturing hole cluster according to the stress shadow;

[0037] S108, determining the fracture spacing corresponding to the mass transfer distance of oil and gas flowing from the matrix to the fractures in the target fracturing section according to the well logging curve, rock sample compression test data, fluid sample compression test data, and fluid viscosity test data;

[0038] S110, determining the fracturing hole cluster spacing according to the minimum value between the influence distance and the fracture spacing.

[0039] The method for determining the spacing of horizontal well fracturing hole clusters provided in the embodiment of the present application is based on well logging curves and fracture simulation to determine the soil characteristics of the target fracturing section, and thereby determine the stress shadow and fracture spacing that can be generated by the fluid released by the fracturing hole clusters for fracturing the soil at the target fracturing section. The minimum value of the stress shadow and the fracture spacing is selected to determine the spacing of the fracturing hole clusters, so that the horizontal wells of the target fracturing section can fully utilize the reservoir, and the adjacent fracturing hole clusters of the horizontal wells are kept at a reasonable cluster spacing.

[0040] In some embodiments of the present application, the stress shadow in step S104 may be implemented by the following steps:

[0041] According to the logging curve and the net pressure fracture fitting results, the stress shadow of the target fracturing section is determined by the analytical expression of the induced stress field generated by the constant height two-dimensional vertical fracture of the isotropic homogeneous linear elastic material;

[0042] Alternatively, the stress shadow of the target fracturing section can be determined by the Boussinet equation based on the well logging curve and the net pressure fracture fitting results.

[0043] In the above embodiment, the analytical expression of the induced stress field generated by the constant-height two-dimensional vertical crack of the isotropic homogeneous linear elastic material can be used to analyze the secondary crack distribution in the stress concentration area, and can describe the singularity of the crack tip in a relatively detailed manner, and can provide a good quantitative description of the early stage of crack expansion. The Boussinet equation is more suitable for far-field stress distribution and the influence of a large range of loads, and the calculation is simple and the results are stable. The staff can choose the above two methods of determining the stress shadow according to the soil properties of the target fracturing section and the required analysis requirements for the crack details.

[0044] In the embodiment of the present application, according to the well logging curve and the net pressure fracture fitting result, the stress shadow of the target fracturing section is determined by the analytical expression of the induced stress field generated by the constant height two-dimensional vertical fracture of the isotropic homogeneous linear elastic material, which may include:

[0045] Determine the average Young's modulus and average Poisson's ratio of the target fracturing section according to the logging curve, and determine the average fracture width and average fracture height of the fracturing section according to the net pressure fracture fitting result;

[0046] According to the average Young's modulus, average Poisson's ratio, average fracture width and average fracture height of the hydraulic fracture, the stress shadow is determined through the analytical expression of the induced stress field generated by the constant-height two-dimensional vertical fracture of the isotropic homogeneous linear elastic material.

[0047] It can be understood that the analytical expression of the induced stress field generated by a constant-height two-dimensional vertical crack in an isotropic homogeneous linear elastic material includes:

[0048]

[0049] Among them, σ xx is the stress perpendicular to the crack direction, p net is the net pressure in the fracture, E is the average Young's modulus in the target fracturing section, W is the average width of the fracture, v is the average Poisson's ratio in the section, a is the height of the fracture. If θ, θ1, θ2 are less than 0, then v, θ1, θ2 are added with ∏.

[0050] Based on the above formulas (1) to (10), σ is determined xx When the term is zero or a value close to 0, the value of x is the maximum distance of the stress shadow, which can be used as the influence distance of the stress shadow of the fracturing hole cluster in step S106 to determine the spacing between the fracturing hole clusters.

[0051] Specifically, determining the average fracture width and average fracture height of the fractured section according to the net pressure fracture fitting result may include: determining the average fracture width and average fracture height of the fractured section according to the production performance analysis of the early fractured well and the net pressure fracture fitting result of the construction curve.

[0052] As an example, determining the average fracture width and average fracture height of a fractured section based on production dynamic analysis of an early fractured well and a net pressure fracture fitting result of a construction curve may include: determining the average fracture width of a fractured section based on optical fiber monitoring of an early fractured well and a net pressure fracture fitting result of a construction curve, and determining the average fracture height of a fractured section based on microseismic monitoring of an early fractured well and a net pressure fracture fitting result of a construction curve.

[0053] In some embodiments of the present application, determining the stress shadow of the target fracturing section through the Boucinnet equation according to the well logging curve and the net pressure fracture fitting result may include:

[0054] Determine the average Young's modulus of the target fracturing section according to the logging curve, and determine the average fracture width of the fracturing section according to the net pressure fracture fitting result;

[0055] According to the average Young's modulus and the average width of the fracturing crack, the stress shadow of the target fracturing section is determined by coupling the shear boundary condition and the Boucinnet equation under the pore-elastic effect.

[0056] It can be understood that the Boucinnet equation under the coupled shear boundary condition and the pore-elastic effect can be, for example,:

[0057]

[0058] Among them, σ is the stress term, Z is the distance from the crack surface, E is the average Young's modulus in the segment, w is the average crack width of the fracturing crack, and t is the variable transverse crack index. In order to meet the solution of ideal linear elastic full coupled deformation, the upper limit of the transverse crack stress index t is 2; the lower limit is 1, which means that there is very strong interference between adjacent cracks. Fiber distributed temperature testing and distributed sound testing (DTS / DAS), as well as other diagnostic tests injected into densely distributed cracks, all show that the transverse crack stress index is 1.2, and t is generally 1.2.

[0059] Based on formula (11), the Z value when σ is zero is determined to be the maximum distance of the stress shadow determined by the Boucinnet equation under the coupled shear boundary condition and the pore-bomb effect. This distance can be used as the influence distance of the stress shadow of the fracturing hole cluster in step S106 to determine the spacing between the fracturing hole clusters.

[0060] In some embodiments of the present application, step S108 may include:

[0061] Determine the permeability and porosity in the fracturing section according to the well logging curve, determine the rock compression coefficient of the rock sample according to the rock sample compression test data, determine the fluid compression coefficient of the fluid sample according to the fluid sample compression test data, and determine the fluid viscosity of the fluid sample according to the fluid viscosity test data;

[0062] Based on the one-dimensional diffusion equation of linear flow, the fracture spacing corresponding to the mass transfer distance is determined according to the permeability, porosity, rock compressibility, fluid compressibility and fluid viscosity.

[0063] It can be understood that the linear flow one-dimensional diffusion equation can be, for example,:

[0064]

[0065] Where τ is the preset production life, l is the mass transfer distance, κ = k / (φB f +B r )η is the hydraulic diffusivity; B f is the fluid compressibility coefficient; B r is the rock compression coefficient; φ is the rock porosity; η is the fluid viscosity of oil and gas; k is the rock permeability, L is the fracture spacing, and α is the power function exponent of the linear flow production time and the fracture spacing. Based on formula (12), after determining the preset linear flow production period, the corresponding fracture spacing L can be obtained.

[0066] Specifically, the compression test data of fluid samples can be obtained through PVT (pressure-volume-temperature) tests and isothermal compression tests of fluid samples; the compression test data of rock samples can be obtained through core compression tests and triaxial compression tests of rock samples; and the fluid viscosity test data can be obtained through capillary viscometer tests and rotational viscometer tests. α can be determined by the slope of the production and material balance time on the double logarithmic graph during bilinear flow in formation fractures and linear flow in formations, and its value can be, for example, 2 or 4.

[0067] In some embodiments of the present application, based on the linear flow one-dimensional diffusion equation, according to the permeability, porosity, rock compressibility, fluid compressibility and fluid viscosity, determining the fracture spacing corresponding to the mass transfer distance may include:

[0068] Based on the linear flow one-dimensional diffusion equation, the relationship between the production life of the production wells in the target fracturing section and the mass transfer distance is determined according to the permeability, porosity, rock compressibility, fluid compressibility and fluid viscosity;

[0069] According to the relationship between the production well life and mass transfer distance of the target fracturing section, the fracture spacing corresponding to the mass transfer distance of the production wells of the target fracturing section under the target production life is determined.

[0070] In the above embodiment, referring to formula (12), there is a correlation between the preset production years and the characteristic diffusion distance. Therefore, according to formula (12), the following equation can be drawn: Figure 3 The relationship curve between production years and mass transfer distance is shown in FIG. Therefore, the staff can select the appropriate production well age to determine the mass transfer distance of the target fracturing section and determine the fracture spacing corresponding to the mass transfer distance based on formula (12).

[0071] In some embodiments of the present application, the stress shadow of the fracturing hole cluster in step S104 is the stress shadow when the fracturing hole cluster has a preset number of open fracturing holes; the fracture spacing corresponding to the mass transfer distance of oil and gas flowing from the matrix to the fracture in step S108 is the fracture spacing corresponding to the mass transfer distance of oil and gas flowing from the matrix to the fracture when the fracturing hole cluster has a preset number of open fracturing holes. The method for determining the spacing of horizontal well fracturing hole clusters provided in the embodiments of the present application, see Figure 2 , and may also include:

[0072] S202, obtaining the number of effective openings of the fracturing hole cluster of the target fracturing section;

[0073] S204, determining an average effective opening ratio of the fracturing hole clusters of the target fracturing section according to the ratio of the number of effective openings to a preset number of fracturing holes;

[0074] Step S110 may include:

[0075] S112. Determine the fracturing hole cluster spacing according to the product of the minimum value of the impact distance and the fracture spacing and the average effective opening ratio.

[0076] In the process of determining the influencing distance and the mass transfer distance, the number of openings of a fracturing hole cluster is generally preset. Since changes in the number of fracturing hole clusters will directly affect the ability of the fluid used for fracturing to expand into the soil, that is, the above-mentioned influencing distance and mass transfer distance will be changed. Therefore, when the method for determining the spacing between fracturing hole clusters in horizontal wells provided in the embodiment of the present application is applied, the spacing between the fracturing hole clusters can be adjusted according to the ratio of the number of effective openings of the target fracturing section to the preset number of fracturing holes. Therefore, if the staff determines the spacing between the fracturing hole clusters in the target fracturing section, then in other fracturing sections with soil properties similar to or the same as the target fracturing section, the spacing between the fracturing hole clusters in the target fracturing section is directly corrected according to the number of openings of its fracturing hole clusters to obtain the corrected spacing between the fracturing hole clusters, and it is applied to the fracturing sections with soil properties similar to or the same as the target fracturing section to achieve the determination of the spacing between the fracturing hole clusters in the horizontal well.

[0077] In some embodiments of the present application, in step S202, determining the number of effective openings may include: determining the number of effective openings of the fracturing hole cluster of the target fracturing section according to the logging curve of the target fracturing section.

[0078] The overall process of the method for determining the spacing between horizontal well fracturing hole clusters provided in the embodiment of the present application is illustrated below by way of example.

[0079] First, for each designated fracturing stage, the cluster spacing within a single stage is determined based on the stress shadow of hydraulic fracturing and the mass transfer distance formula for oil and gas flowing from the matrix to the fracture.

[0080] Specifically, the fracturing section may be divided into at least one section according to the distribution of the fracturing effect evaluation index of the volume fracturing horizontal well fracturing section, and the reservoir types to which adjacent sections belong are different; and the cluster spacing corresponding to each reservoir type is determined respectively.

[0081] The above-mentioned fracturing effect evaluation index characterizes the potential fracturing effect of the reservoir. For example, the fracturing effect evaluation index classification of each section can be made. The fracturing effect evaluation index has two types of indicators, namely reservoir quality and engineering quality. The sections with a fracturing effect evaluation index of "GG" within the preset range, that is, the reservoir quality and engineering quality are both "GOOD", are classified into Class I reservoirs, the sections with a fracturing effect evaluation index of "GB" and "BG", that is, the reservoir quality and engineering quality are one "GOOD" and the other "BAD", are classified into Class II reservoirs, and the sections with a fracturing effect evaluation index of "BB", that is, the reservoir quality and engineering quality are both "BAD", are classified into Class III reservoirs.

[0082] Then, the cluster spacing corresponding to each type of reservoir is determined for each type of reservoir. Take the cluster spacing determination of one type of reservoir as an example.

[0083] The cluster spacing within a single segment is determined based on the stress shadow of hydraulic fracturing and the mass transfer distance formula for oil and gas flowing from the matrix to the fracture. The stress shadow of hydraulic fracturing is determined by the analytical expression (plane strain condition) of the induced stress field generated by the constant height two-dimensional vertical fracture as shown in formulas (1) to (10) or the Boucinnet equation as shown in formula (11), and the formula for the effective distance of seepage mass transfer includes the linear flow one-dimensional diffusion equation as shown in formula (12).

[0084] Determine the distance A without stress shadow influence in a single section; determine the fracture spacing B corresponding to the seepage mass transfer distance within a fixed production period in a single section.

[0085] The above analytical expression of the stress field induced by the constant-height two-dimensional vertical crack can be based on the linear elastic theory, without the existence of shear plane or poroelastic effect. The Boucinnet equation can be based on the linear elastic homogeneous isotropic medium and can fully characterize the stress shadow after pumping is stopped.

[0086] The distance A without stress shadow influence can be determined by the value corresponding to the analytical expression of the constant height two-dimensional vertical crack induced stress field in formula (1) when it approaches 0, or the value corresponding to the Boucinnet equation in formula (11) when it approaches 0.

[0087] According to experimental data, the rock compression coefficient of a well in a certain oil field is 6×10 -11 Pa -1 , fluid compressibility coefficient 3×10 -8 Pa -1 , fluid viscosity 3.5×10 -5 Pa·s, the logging curve in a certain fracturing section shows an average permeability of 1 microdarcy, an average porosity of 0.09, an average Young's modulus of 40 GPa, and an average Poisson's ratio of 0.2. According to the production dynamic analysis and fracture fitting of the previous fractured wells, the hydraulic fracture height is 20m and the fracture width is 0.008m. Calculated by formulas (1) to (10), for example Figure 4 As shown in Figure 1, when the distance from the fracture surface is 40 m, the induced stress is very small and the amplitude of change is also small, so the minimum distance without stress shadow is 40 m. Or it can be calculated by formula (11), for example Figure 5 As shown, when 40m away from the crack surface, the induced stress is very small and the amplitude of change also becomes smaller, so the minimum distance without stress shadow is 40m.

[0088] The percolation mass transfer distance within a fixed production period in a single section can be the mass transfer distance corresponding to the average production period of oil and gas wells in the development area. Figure 3As shown in Figure 1, if the general production life of an oil and gas well is 3 years, the mass transfer distance is 30 m. Combining this with formula (12), the fracture spacing corresponding to the mass transfer distance can be obtained.

[0089] After obtaining the distance A without stress shadow influence and the fracture spacing B corresponding to the mass transfer distance within the fixed production life, the minimum value is multiplied by the perforation opening rate to obtain the engineering cluster spacing. For example, based on the smaller value of A and B, 30m is taken, and the perforation opening rate is 60% based on the experience of the development block, then the engineering cluster spacing is 18m.

[0090] The embodiment of the present application further provides a device for determining the spacing between fracturing hole clusters in a horizontal well, which may include: a memory and a storage.

[0091] The memory is configured to store instructions. The processor is configured to call the instructions from the memory and implement the method for determining the spacing between fracturing hole clusters in a horizontal well according to any one of the above embodiments when executing the instructions.

[0092] An embodiment of the present application further provides a machine-readable storage medium having instructions stored thereon, the instructions being used to enable a machine to execute the method for determining the spacing between horizontal well fracturing hole clusters provided in any one of the above embodiments.

[0093] Those skilled in the art will appreciate that the embodiments of the present application may be provided as methods, systems or computer program products. Therefore, the present application may adopt the form of a complete hardware embodiment, a complete software embodiment or an embodiment in combination with software and hardware. Moreover, the present application may adopt the form of a computer program product implemented on one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) that contain computer-usable program code.

[0094] The present application is described with reference to the flowcharts and / or block diagrams of the methods, devices (systems), and computer program products according to the embodiments of the present application. It should be understood that each process and / or box in the flowchart and / or block diagram, as well as the combination of the processes and / or boxes in the flowchart and / or block diagram, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, a special-purpose computer, an embedded processor, or other programmable data processing device to generate a machine, so that the instructions executed by the processor of the computer or other programmable data processing device generate instructions for implementing the processes in the flowchart and / or block diagram. Figure 1 A process or multiple processes and / or boxes Figure 1 A device that provides the functions specified in a block or multiple blocks.

[0095] These computer program instructions may also be stored in a computer-readable memory capable of directing a computer or other programmable data processing device to operate in a specific manner, so that the instructions stored in the computer-readable memory produce an article of manufacture comprising an instruction device, which implements the process Figure 1 A process or multiple processes and / or boxes Figure 1 A function specified in one or more boxes.

[0096] These computer program instructions can also be loaded onto a computer or other programmable data processing device so that a series of operating steps are executed on the computer or other programmable device to produce a computer-implemented process, thereby providing instructions for implementing the process. Figure 1 A process or multiple processes and / or boxes Figure 1 The steps for the functions specified in one or more boxes.

[0097] In a typical configuration, a computing device includes one or more processors (CPU), input / output interfaces, network interfaces, and memory.

[0098] The memory may include non-permanent memory in a computer-readable medium, random access memory (RAM) and / or non-volatile memory in the form of read-only memory (ROM) or flash RAM. The memory is an example of a computer-readable medium.

[0099] Computer readable media include permanent and non-permanent, removable and non-removable media that can be implemented by any method or technology to store information. Information can be computer readable instructions, data structures, program modules or other data. Examples of computer storage media include, but are not limited to, phase change memory (PRAM), static random access memory (SRAM), dynamic random access memory (DRAM), other types of random access memory (RAM), read-only memory (ROM), electrically erasable programmable read-only memory (EEPROM), flash memory or other memory technology, compact disk read-only memory (CD-ROM), digital versatile disk (DVD) or other optical storage, magnetic cassettes, magnetic disk storage or other magnetic storage devices or any other non-transmission media that can be used to store information that can be accessed by a computing device. As defined herein, computer readable media does not include temporary computer readable media (transitory media), such as modulated data signals and carrier waves.

[0100] It should also be noted that the terms "include", "comprises" or any other variations thereof are intended to cover non-exclusive inclusion, so that a process, method, commodity or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, commodity or device. In the absence of more restrictions, the elements defined by the sentence "comprises a ..." do not exclude the existence of other identical elements in the process, method, commodity or device including the elements.

[0101] The above are only embodiments of the present application and are not intended to limit the present application. For those skilled in the art, the present application may have various changes and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application should be included within the scope of the claims of the present application.

Claims

1. A method for determining the spacing between fracturing hole clusters in a horizontal well, characterized in that: include: Acquire a well logging curve of a target fracturing section, a net pressure fracture fitting result of the target fracturing section, rock sample compression experimental data of the target fracturing section, and fluid sample compression experimental data of the target fracturing section and fluid viscosity experimental data of the fluid sample; Determining the stress shadow of the fracturing hole cluster of the target fracturing section according to the well logging curve and the net pressure fracture fitting result; Determining the influence distance of the stress shadow of the fracturing hole cluster according to the stress shadow; Determine the fracture spacing corresponding to the mass transfer distance of oil and gas flowing from the matrix to the fractures in the target fracturing section according to the well logging curve, the rock sample compression test data, the fluid sample compression test data and the fluid viscosity test data; The fracturing hole cluster spacing is determined according to the minimum value between the influence distance and the fracture spacing.

2. The method according to claim 1, characterized in that The step of determining the stress shadow of the fracturing hole cluster of the target fracturing section according to the well logging curve and the net pressure fracture fitting result comprises: According to the well logging curve and the net pressure fracture fitting result, the stress shadow of the target fracturing section is determined by an analytical expression of the induced stress field generated by a constant-height two-dimensional vertical fracture of an isotropic homogeneous linear elastic material; Alternatively, the stress shadow of the target fracturing section is determined according to the well logging curve and the net pressure fracture fitting result by using the Boucinnet equation.

3. The method according to claim 2, characterized in that The determining of the stress shadow of the target fracturing section according to the well logging curve and the net pressure fracture fitting result by using an analytical expression of the induced stress field generated by a constant-height two-dimensional vertical fracture of an isotropic homogeneous linear elastic material comprises: Determine the average Young's modulus and the average Poisson's ratio of the target fracturing section according to the logging curve, and determine the average fracture width and the average fracture height of the fracturing section according to the net pressure fracture fitting result; The stress shadow is determined according to the average Young's modulus, the average Poisson's ratio, the average fracture width of the hydraulic fracture and the average fracture height of the hydraulic fracture, by using an analytical expression for the induced stress field generated by a constant-height two-dimensional vertical fracture of an isotropic homogeneous linear elastic material.

4. The method according to claim 2, characterized in that: The step of determining the stress shadow of the target fracturing section by using the Boucinnet equation according to the well logging curve and the net pressure fracture fitting result includes: Determine the average Young's modulus of the target fracturing section according to the logging curve, and determine the average fracture width of the fracturing cracks in the fracturing section according to the net pressure fracture fitting result; According to the average Young's modulus and the average width of the fracturing crack, the stress shadow of the target fracturing section is determined by coupling the shear boundary condition and the Boucinnet equation under the poroelastic effect.

5. The method according to claim 1, characterized in that The method of determining the fracture spacing corresponding to the mass transfer distance of oil and gas flowing from the matrix to the fractures in the target fracturing section according to the well logging curve, the rock sample compression test data, the fluid sample compression test data and the fluid viscosity test data comprises: Determine the permeability and porosity in the fracturing section according to the well logging curve, determine the rock compression coefficient of the rock sample according to the rock sample compression test data, determine the fluid compression coefficient of the fluid sample according to the fluid sample compression test data, and determine the fluid viscosity of the fluid sample according to the fluid viscosity test data; Based on a linear flow one-dimensional diffusion equation, the fracture spacing corresponding to the mass transfer distance is determined according to the permeability, the porosity, the rock compressibility, the fluid compressibility and the fluid viscosity.

6. The method according to claim 1, characterized in that The stress shadow of the fracturing hole cluster is the stress shadow when the fracturing hole cluster has a preset number of open fracturing holes; the fracture spacing corresponding to the mass transfer distance of oil and gas flowing from the matrix to the fracture is the fracture spacing corresponding to the mass transfer distance of oil and gas flowing from the matrix to the fracture when the fracturing hole cluster has a preset number of open fracturing holes; The method further comprises: Obtaining the effective opening number of the fracturing hole cluster of the target fracturing section; Determining an average effective opening ratio of the fracturing hole clusters of the target fracturing section according to the ratio of the effective opening number to the preset number of fracturing holes; The step of determining the fracturing hole cluster spacing according to the minimum value of the influence distance and the fracture spacing comprises: The fracturing hole cluster spacing is determined according to the product of the minimum value and the average effective opening ratio.

7. The method according to claim 6, characterized in that The step of obtaining the effective number of openings of the fracturing hole cluster of the target fracturing stage includes: The effective opening number of the fracturing hole cluster of the target fracturing section is determined according to the well logging curve of the target fracturing section.

8. The method according to claim 5, characterized in that The method of determining the fracture spacing corresponding to the mass transfer distance based on the linear flow one-dimensional diffusion equation according to the permeability, the porosity, the rock compressibility, the fluid compressibility and the fluid viscosity comprises: Based on the linear flow one-dimensional diffusion equation, according to the permeability, the porosity, the rock compressibility, the fluid compressibility and the fluid viscosity, determining the relationship between the production life of the production well of the target fracturing section and the mass transfer distance; According to the relationship between the production well life and the fracture spacing of the target fracturing section, the fracture spacing of the production well of the target fracturing section under the target production life is determined.

9. A device for determining the spacing between fracturing hole clusters in a horizontal well, characterized in that: include: a memory configured to store instructions; as well as A processor is configured to call the instructions from the memory and implement the method for determining the spacing between fracturing hole clusters in a horizontal well according to any one of claims 1 to 8 when executing the instructions.

10. A machine-readable storage medium, characterized in that: The machine-readable storage medium stores instructions for causing a machine to execute the method for determining the spacing between fracturing hole clusters in a horizontal well according to any one of claims 1 to 8.

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