Method and system for evaluating contribution rate of crack to single well yield, storage medium and equipment

Abstract

The invention belongs to the technical field of oil field transformation, and provides a method and system for evaluating the contribution rate of a crack to single well yield, a storage medium and equipment, and the method comprises the steps: determining a geomechanical model of a single well reservoir based on a matrix geologic model; based on the geomechanical model, generating a primary fracturing crack propagation model; based on the primary fracturing crack propagation model, generating a primary fracturing single well yield relation curve within a first preset duration, and determining a single well primary commissioning model; based on the single well primary commissioning model, a refracturing crack propagation model is obtained; based on the refracturing crack propagation model, generating a refracturing single well yield relation curve within a second preset duration; and quantitatively evaluating the single well yield contribution rate according to the primary fracturing single well yield relation curve and the repeated fracturing single well yield relation curve. The yield of the single well after primary fracturing and repeated fracturing is quantitatively analyzed, the yield contribution degree of the single well in different production periods is determined, the evaluation result is accurate, the technology application cost is low, and the generalization performance is high.

Description

Technical Field

[0001] This disclosure belongs to the field of oilfield stimulation technology, and in particular relates to a method, system, storage medium and equipment for evaluating the contribution rate of fractures to single-well production. Background Technology

[0002] To enable the repeated development of old oil wells in the reservoir, it is necessary to evaluate the effect of repeated fracturing of old oil wells and optimize the fracturing parameters of oil wells. Therefore, it is necessary to conduct quantitative analysis on the production of a single well after the initial fracturing and the production of a single well after repeated fracturing.

[0003] In the prior art, patent application CN201510764702.1 discloses a quantitative evaluation method for the contribution of fractures and matrix to the production of a single well in an ultra-low permeability reservoir. This method establishes a model for a single well to be put into production only after its initial fracturing, used to evaluate the degree of contribution of fractures and matrix to the production of a single well in an ultra-low permeability reservoir. Patent application CN202110392226.0 discloses an intelligent releaseable tracer production profile testing experimental device and method, used to evaluate the contribution of each fracture segment to the production of a single well, but it cannot evaluate the effect of repeated fracturing stimulation of old oil wells.

[0004] In summary, current methods such as production profile testing and fiber optic testing are commonly used to evaluate the contribution of each fracturing segment to the production of a single well over a certain period of time. However, there is a lack of accurate evaluation of the contribution rate of repeated fracturing fractures and primary fracturing fractures to the production of a single well after repeated fracturing has been put into production. Summary of the Invention

[0005] To address the aforementioned issues, this disclosure provides a method, system, storage medium, and equipment for evaluating the contribution of fractures to single-well production. It establishes an initial fracturing fracture propagation model to simulate the production relationship curve of a single well after a first preset production period following initial fracturing. A repeated fracturing fracture propagation model is then established to simulate the production relationship curve of a single well after a second preset production period following repeated fracturing. Based on the production relationship curves of the initial and repeated fracturing operations, the contribution of single-well production is quantitatively evaluated, enabling quantitative analysis of both the production after initial fracturing and the production after repeated fracturing.

[0006] This invention is achieved through the following technical solution:

[0007] In a first aspect, embodiments of this disclosure provide a method for evaluating the contribution rate of fractures to single-well production, the method comprising:

[0008] Establish a matrix geological model of the reservoir where the target well is located, and determine the geomechanical model of the reservoir based on the matrix geological model;

[0009] Based on the geomechanical model, the initial hydraulic fracturing fracture propagation result is determined, and the initial hydraulic fracturing fracture propagation result is coupled to the matrix geological model to generate the initial hydraulic fracturing fracture propagation model.

[0010] Based on the initial fracturing fracture propagation model, the first preset time for the initial production of a single well is simulated, and the production relationship curve of the single well during the first preset time is generated to determine the initial production model of the single well.

[0011] Based on the single-well initial production model, the repeated fracturing fracture propagation results are determined, and the repeated fracturing fracture propagation results are coupled to the single-well initial production model to obtain the repeated fracturing fracture propagation model.

[0012] Based on the repeated fracturing fracture propagation model, a second preset duration of repeated production of a single well is simulated, and a production relationship curve of a single well during the second preset duration of repeated fracturing is generated.

[0013] The contribution rate of single-well production is quantitatively evaluated based on the production relationship curves of the first fracturing single well and the repeated fracturing single well.

[0014] Furthermore,

[0015] Acquire well point stratification data, sedimentary microfacies data, multi-well logging data, and single-well logging data for the target single well;

[0016] Using the well point stratification data, an initial structural model is determined; based on the initial structural model and the sedimentary microfacies data, a facies model is established.

[0017] Based on the phase model, an attribute model is established according to the multi-well logging data, and the matrix geological model of the reservoir where the target well is located is determined.

[0018] Based on the matrix geological model, Young's modulus, Poisson's ratio, maximum and minimum principal stresses, and vertical stress data are calculated using the single-well logging data to establish the geomechanical model of the single-well reservoir.

[0019] Furthermore,

[0020] Based on the aforementioned geomechanical model, the fracture propagation trajectory of the initial fracturing is calculated according to the initial fracturing perforation location and pumping procedure.

[0021] Based on the fracture propagation trajectory of the initial fracturing, the fracture is discretized into multiple fracture segments, and a natural fracture mesh is generated to determine the fracture propagation result of the initial fracturing.

[0022] The initial hydraulic fracturing fracture propagation results are coupled to the matrix geological model to generate the initial hydraulic fracturing fracture propagation model; wherein, the initial hydraulic fracturing fracture propagation model includes the natural fracture grid and the original matrix fracture grid.

[0023] Furthermore,

[0024] A dual-pore dual-permeability black oil model was adopted, and the relative permeability curves of the target reservoir, high-temperature and high-pressure PVT data, and initial parameters for model calculation were set.

[0025] The initial fracturing fracture propagation model is divided into partitions: the natural fracture mesh is divided into partition I, and the original matrix fracture mesh is divided into partition II. Based on the initial parameters and the initial fracturing fracture propagation model, the first preset time for the initial production of a single well is simulated, and the average production rate of the single well during the initial production is determined.

[0026] The production curves for Zone I and Zone II are generated based on the average single-well production during the initial production period, and the production relationship curve of the single well during the initial fracturing within the first preset time period is obtained to determine the single-well initial production model.

[0027] Furthermore,

[0028] Based on the single-well initial production model, the fracture propagation trajectory of repeated fracturing is calculated according to the perforation location and pumping procedure of repeated fracturing.

[0029] Based on the fracture propagation trajectory of repeated fracturing, the fracture is discretized into multiple fracture segments, and an artificial fracture mesh of repeated fracturing is generated to determine the fracture propagation result of repeated fracturing.

[0030] The repeated fracturing fracture propagation results are coupled to the single-well initial production model to generate a repeated fracturing fracture propagation model; wherein, the repeated fracturing fracture propagation model includes a natural fracture grid, an original matrix fracture grid, and the repeated fracturing artificial fracture grid.

[0031] Furthermore,

[0032] The repeated fracturing fracture propagation model is divided into partitions: the repeated fracturing artificial fracture mesh is divided into partition III, the natural fracture mesh is divided into partition IV, and the original matrix fracture mesh is divided into partition V. Based on the initial parameters and the repeated fracturing fracture propagation model, the second preset duration of repeated production of a single well is simulated, and the average production per well during repeated production is determined.

[0033] The production curves for zones III, IV, and V are generated based on the average production of a single well during repeated production, and the production relationship curve of a single well during repeated fracturing within the second preset time period is obtained.

[0034] Furthermore,

[0035] Based on the initial fracturing single-well production relationship curve, calculate the ratio of the production of zone I within the first preset time period to the total production of zone I and zone II within the first preset time period;

[0036] Based on the repeated fracturing single-well production relationship curve, calculate the ratio of the production of zone III within the second preset time period to the total production of zones III, IV, and V within the second preset time period; based on the repeated fracturing single-well production relationship curve, calculate the ratio of the production of zone IV within the second preset time period to the total production of zones III, IV, and V within the second preset time period.

[0037] Secondly, this disclosure provides a system for evaluating the contribution of fractures to single-well production, the system comprising: a single-well model establishment module, a single-well fracture propagation module, a single-well production analysis module, and a single-well contribution analysis module;

[0038] The single-well model establishment module is used to establish a matrix geological model of the reservoir where the target single well is located, and to determine the geomechanical model of the single-well reservoir based on the matrix geological model.

[0039] The single-well fracture propagation module is used to determine the initial fracturing fracture propagation result based on the geomechanical model, couple the initial fracturing fracture propagation result to the matrix geological model to generate the initial fracturing fracture propagation model; and determine the repeated fracturing fracture propagation result based on the single-well initial production model, couple the repeated fracturing fracture propagation result to the single-well initial production model to obtain the repeated fracturing fracture propagation model.

[0040] The single-well production analysis module is used to simulate the first preset time for the initial production of a single well based on the initial fracturing fracture propagation model, generate the initial fracturing single-well production relationship curve within the first preset time, and determine the single-well initial production model; and to simulate the second preset time for repeated production of a single well based on the repeated fracturing fracture propagation model, generate the repeated fracturing single-well production relationship curve within the second preset time.

[0041] The single-well contribution analysis module is used to quantitatively evaluate the production contribution rate of a single well based on the production relationship curve of the first fracturing single well and the production relationship curve of the repeated fracturing single well.

[0042] Thirdly, based on the same inventive concept, the present disclosure also provides a computer-readable storage medium storing one or more programs, which, when executed, can realize the aforementioned method for evaluating the contribution rate of fractures to single-well production.

[0043] Fourthly, based on the same inventive concept, embodiments of this disclosure also provide an electronic device, including a processor, a communication interface, the aforementioned computer-readable storage medium, and a communication bus. The processor, communication interface, and computer-readable storage medium communicate with each other via the communication bus. The processor is used to execute a program stored in the computer-readable storage medium.

[0044] Compared with the prior art, this disclosure has the following advantages:

[0045] It can quantitatively analyze the production output of a single well after initial fracturing and after repeated fracturing, clarify the contribution of initial fracturing and repeated fracturing to the production output of a single well in different production periods, and the evaluation results are accurate. The technology has low application cost and strong scalability.

[0046] Other features and advantages of this disclosure will be set forth in the description which follows, and will be apparent in part from the description, or may be learned by practicing the disclosure. The objects and other advantages of this disclosure may be realized and obtained by means of the structures pointed out in the description, claims and drawings. Attached Figure Description

[0047] To more clearly illustrate the technical solutions in the embodiments of this disclosure or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of this disclosure. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0048] Figure 1 A flowchart of a method for evaluating the contribution of fractures to single-well production provided in this embodiment of the disclosure;

[0049] Figure 2 A schematic diagram of the matrix geological model provided in the embodiments of this disclosure;

[0050] Figure 3 A schematic diagram of the geomechanical model provided in the embodiments of this disclosure;

[0051] Figure 4 This is a schematic diagram of the crack propagation trajectory after the initial fracturing, provided in an embodiment of the present disclosure.

[0052] Figure 5 This is a schematic diagram of the initial hydraulic fracturing fracture propagation model provided in an embodiment of this disclosure;

[0053] Figure 6 The initial fracturing single-well production relationship curve provided in the embodiments of this disclosure;

[0054] Figure 7 The production relationship curve of a single well subjected to repeated fracturing is provided in the embodiments of this disclosure;

[0055] Figure 8 This is a schematic diagram of an electronic device structure provided in an embodiment of the present disclosure. Detailed Implementation

[0056] To make the objectives, technical solutions, and advantages of the embodiments of this disclosure clearer, the technical solutions of the embodiments of this disclosure will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this disclosure, and not all embodiments. Based on the embodiments of this disclosure, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this disclosure.

[0057] Firstly, Figure 1 A flowchart illustrating the method for evaluating the contribution of fractures to single-well production provided in this embodiment of the disclosure is shown below. Figure 1 As shown in the embodiments of this disclosure, the method for evaluating the contribution rate of fractures to single-well production includes:

[0058] S1: Establish a matrix geological model of the reservoir where the target well is located, and determine the geomechanical model of the reservoir based on the matrix geological model.

[0059] S2: Based on the geomechanical model, determine the initial hydraulic fracturing fracture propagation results, and couple the initial hydraulic fracturing fracture propagation results to the matrix geological model to generate the initial hydraulic fracturing fracture propagation model.

[0060] S3: Based on the initial fracturing fracture propagation model, simulate the first preset time for initial production of a single well, generate the initial fracturing single well production relationship curve within the first preset time, and determine the single well initial production model.

[0061] S4: Based on the initial production model of a single well, determine the fracture propagation results of repeated fracturing, and couple the fracture propagation results of repeated fracturing to the initial production model of a single well to obtain the fracture propagation model of repeated fracturing.

[0062] S5: Based on the repeated fracturing fracture propagation model, simulate the second preset time for repeated production of a single well, and generate the production relationship curve of the repeated fracturing single well within the second preset time.

[0063] S6: Quantitatively evaluate the production contribution rate of a single well based on the production relationship curves of the first fracturing and the repeated fracturing.

[0064] This disclosure provides a method for evaluating the contribution of fractures to single-well production. It establishes an initial fracturing fracture propagation model to simulate the production relationship curve of a single well after a first preset production time following initial fracturing. It then establishes a repeated fracturing fracture propagation model to simulate the production relationship curve of a single well after a second preset production time following repeated fracturing. Based on the production relationship curves of the initial and repeated fracturing operations, the contribution of single-well production is quantitatively evaluated, enabling quantitative analysis of both the production after initial fracturing and the production after repeated fracturing of a single well.

[0065] In some examples, a matrix geological model of the reservoir where the target well is located is established, and a geomechanical model of the reservoir of the single well is determined based on the matrix geological model. Specifically, this includes:

[0066] S11: Acquire well point stratification data, sedimentary microfacies data, multi-well logging data, and single-well logging data of the target single well.

[0067] Specifically, single-well logging data refers to a series of logging information and data obtained from logging operations on a single well. The single-well logging data in this disclosure can be determined from the single-well logging curves obtained from logging operations. Multi-well logging data, on the other hand, refers to a series of logging information and data obtained from logging operations on multiple single wells, used to understand and evaluate the subsurface geological conditions, reservoir characteristics, and oil and gas resource potential of the reservoir.

[0068] S12: Use well point stratification data to determine the initial structural model; based on the initial structural model, combine sedimentary microfacies data to establish a facies model.

[0069] Specifically, using well point layered data and the Kriging interpolation algorithm, an initial structural model is obtained; based on the initial structural model, sedimentary microfacies data are integrated, and a facies model is established through stochastic simulation and the variation function method.

[0070] S13: Based on the phase model, establish the attribute model according to the logging data of multiple wells, and determine the matrix geological model of the reservoir where the target single well is located.

[0071] Specifically, based on the phase model, variation function fitting is performed using multi-well logging data to establish an attribute model and determine the matrix geological model of the reservoir where the target well is located.

[0072] S14: Based on the matrix geological model, Young's modulus, Poisson's ratio, maximum and minimum principal stresses, and vertical stress data are calculated using single-well logging data to establish a geomechanical model of the single-well reservoir.

[0073] In some examples, based on a geomechanical model, the initial fracture propagation results are determined, and these results are coupled to a matrix geological model to generate an initial fracture propagation model. Specifically, this includes:

[0074] S21: Based on the geomechanical model, the fracture propagation trajectory of the initial fracturing is calculated according to the location of the initial fracturing perforation and the pumping procedure.

[0075] Specifically, based on the geomechanical model, the fracture propagation trajectory after the initial fracturing is calculated according to the location of the initial fracturing perforation and the pumping procedure. The simulation can be completed using complex fracture propagation software, and the fracture propagation trajectory after the initial fracturing can be calculated.

[0076] S22: Based on the fracture propagation trajectory of the initial fracturing, the fracture is discretized into multiple fracture segments, and a natural fracture mesh is generated to determine the fracture propagation result of the initial fracturing.

[0077] Specifically, using the embedded discrete fracture method, the fracture propagation trajectory of the initial fracturing is discretized into several fracture segments, which will generate a fracture mesh. The fracture mesh includes fractures and fracture segments. The fracture mesh is converted into a natural fracture format, and a natural fracture grid is generated based on the converted fracture mesh. The fracture propagation result of the initial fracturing is then determined.

[0078] S23: Couple the initial hydraulic fracturing fracture propagation results to the matrix geological model to generate the initial hydraulic fracturing fracture propagation model.

[0079] Specifically, by using the equivalent of natural fractures, the results of the initial hydraulic fracturing fracture propagation are coupled to the matrix geological model through the embedded discrete fracture method to generate the initial hydraulic fracturing fracture propagation model; wherein, the initial hydraulic fracturing fracture propagation model includes natural fracture mesh and original matrix fracture mesh.

[0080] Furthermore, the matrix geological model includes a structured numerical simulation model grid. The results of the initial fracturing are embedded into the structured numerical simulation model grid, which together with the matrix network of the reservoir forms an unstructured grid. This allows the results of the initial fracturing to be coupled to the matrix geological model, thus determining the initial fracturing model.

[0081] In some examples, based on the initial fracturing fracture propagation model, the initial production time of a single well is simulated for a first preset duration, generating the initial fracturing single-well production relationship curve within the first preset duration, thus determining the single-well initial production model, specifically including:

[0082] S31: A dual-pore dual-permeability black oil model is adopted, and the relative permeability curves of the target reservoir, high-temperature and high-pressure PVT data, and initial parameters for model calculation are set.

[0083] Specifically, by interfacing with external software, making manual adjustments, or using other methods commonly used in the field, one can use reservoir numerical simulation software or other reservoir numerical simulation software to adopt a dual-pore dual-permeability black oil model, and set the relative permeability curves, high-temperature and high-pressure PVT data, and initial parameters for model calculation of the target reservoir.

[0084] S32: Divide the initial fracturing fracture propagation model into partitions, divide the natural fracture mesh into partition I, and divide the original matrix fracture mesh into partition II. Based on the initial parameters and the initial fracturing fracture propagation model, simulate the first preset time for the initial production of a single well and determine the average production rate of the single well during the initial production.

[0085] Specifically, the initial fracturing fracture propagation model can be partitioned by interfacing with external software, manual adjustment, or other methods commonly used in the field. The natural fracture grid is divided into partition I, and the original matrix fracture grid is divided into partition II. Based on the initial parameters determined in step S31, the first preset time for the initial production of a single well is simulated based on the initial fracturing fracture propagation model, and the average production rate of a single well during the initial production is determined.

[0086] S33: Generate production curves for Zone I and Zone II based on the average single-well production during the initial production period, and obtain the single-well production relationship curve during the first preset time period to determine the single-well initial production model.

[0087] Specifically, by interfacing with external software, making manual adjustments, or using other methods commonly used in the field, production curves for Zone I and Zone II can be generated based on the average single-well production during the initial production run. These curves can then be analyzed to generate the initial fracturing single-well production relationship curve within the first preset time period, thus determining the single-well initial production model. The single-well initial production model is the geological model simulated by the initial fracturing fracture propagation model after the first preset time period of production.

[0088] In some examples, based on the initial production model of a single well, the propagation results of repeated fracturing are determined. These repeated fracturing propagation results are then coupled to the initial production model of the single well to obtain a repeated fracturing propagation model, specifically including:

[0089] S41: Based on the initial production model of a single well, the fracture propagation trajectory of repeated fracturing is calculated according to the location of the repeated fracturing perforation and the pumping procedure.

[0090] Specifically, based on the initial production model of a single well, the fracture propagation trajectory after repeated fracturing is calculated according to the perforation location and pumping procedure. This can be simulated using complex fracture propagation software, and the fracture propagation trajectory after repeated fracturing can be calculated.

[0091] S42: Based on the fracture propagation trajectory of repeated fracturing, the fracture is discretized into multiple fracture segments, and an artificial fracture mesh of repeated fracturing is generated to determine the fracture propagation result of repeated fracturing.

[0092] Specifically, the embedded discrete fracture method is used to discretize the fracture propagation trajectory of repeated fracturing into several fracture segments, generate an artificial fracture mesh for repeated fracturing, and determine the fracture propagation result of repeated fracturing.

[0093] S43: Couple the repeated fracturing fracture propagation results to the single-well initial production model to generate a repeated fracturing fracture propagation model.

[0094] Specifically, the results of repeated fracturing fracture propagation are coupled to the initial production model of a single well to ultimately determine the repeated fracturing fracture propagation model. This model includes a natural fracture grid, a primary matrix fracture grid, and a repeated fracturing artificial fracture grid. Understandably, the natural fracture grid and the primary matrix fracture grid at this stage represent the grids generated after the first preset production duration simulated by the initial fracturing fracture propagation model.

[0095] Furthermore, the repeated fracturing fracture propagation results are coupled to the single-well initial production model using the embedded discrete fracture method to generate a repeated fracturing fracture propagation model.

[0096] In some examples, based on the repeated fracturing fracture propagation model, the second preset duration of repeated production in a single well is simulated, generating a production relationship curve for the repeated fracturing single well within the second preset duration, specifically including:

[0097] S51: Divide the repeated fracturing fracture propagation model into partitions. Divide the repeated fracturing artificial fracture mesh into partition III, the natural fracture mesh into partition IV, and the original matrix fracture mesh into partition V. Based on the initial parameters, simulate the second preset duration of repeated production of a single well based on the repeated fracturing fracture propagation model, and determine the average production per well during repeated production.

[0098] Specifically, the repeated fracturing fracture propagation model is divided into zones: the repeated fracturing artificial fracture grid is divided into zone III, the natural fracture grid is divided into zone IV, and the original matrix fracture grid is divided into zone V. Based on the initial parameters determined in step S31, the second preset duration of repeated production of a single well is simulated based on the repeated fracturing fracture propagation model, and the average production per well during repeated production is determined.

[0099] S52: Generate production curves for zones III, IV and V based on the average production of a single well during repeated production, and obtain the production relationship curve of a single well during repeated fracturing within a second preset time period.

[0100] Specifically, by interfacing with external software, manually adjusting, or using other methods commonly used in the field, production curves for zones III, IV, and V can be generated based on the average production of repeated fracturing wells. These curves can then be analyzed to generate a production relationship curve for repeated fracturing wells within a second preset time period.

[0101] In some examples, the contribution rate of single-well production is quantitatively evaluated based on the production relationship curves of single wells after initial fracturing and those after repeated fracturing. Specifically, this includes:

[0102] S61: Based on the initial fracturing single-well production relationship curve, calculate the ratio of the production of zone I within the first preset time period to the total production of zone I and zone II within the first preset time period.

[0103] S62: Based on the production relationship curve of a single well undergoing repeated fracturing, calculate the ratio of the production of zone III within the second preset time period to the total production of zones III, IV, and V within the second preset time period; based on the production relationship curve of a single well undergoing repeated fracturing, calculate the ratio of the production of zone IV within the second preset time period to the total production of zones III, IV, and V within the second preset time period.

[0104] Based on the three ratios calculated in steps S61 and S62, a quantitative evaluation of the single-well production contribution rate is completed. On this basis, the effect of repeated fracturing of old oil wells is evaluated, and the fracturing parameters of oil wells are optimized.

[0105] This disclosure provides a method for evaluating the contribution of fractures to single-well production. It can quantitatively analyze the production rate of a single well after initial fracturing and after repeated fracturing, clarifying the contribution of initial and repeated fracturing to the production rate of a single well at different production stages. The evaluation results are accurate, and the technology has low application cost and strong applicability. It has significant guiding significance for evaluating the effect of repeated fracturing stimulation of old oil wells, optimizing fracturing parameters, and formulating technical policies.

[0106] In this embodiment, the method for evaluating the contribution of fractures to single-well production provided in this disclosure and methods in the prior art were used to quantitatively analyze the production of five single wells after initial fracturing and after repeated fracturing. The quantitative analysis results determined by the method in this disclosure have a fitting rate of over 82.4% with the quantitative analysis results determined by methods in the prior art, ensuring accuracy while offering advantages of high reliability and low computational cost. The prior art includes production profile testing technology.

[0107] Example 1:

[0108] This embodiment takes a target single well in Changqing Oilfield, with both the first and second preset durations being ten years, as an example to quantitatively evaluate the single well production contribution rate of the target single well after initial fracturing and the single well production contribution rate after repeated fracturing.

[0109] Acquire wellpoint stratification data, sedimentary microfacies data, multi-well logging data, and single-well logging data for the target well. Using the wellpoint stratification data, determine the initial structural model using the Kriging interpolation algorithm. Based on the initial structural model, integrate the sedimentary microfacies data and establish a facies model through stochastic simulation and the variogram method. Based on the facies model, use multi-well logging data to perform variogram fitting to establish a property model and determine the matrix geological model of the reservoir where the target well is located. Based on the matrix geological model, use single-well logging data to calculate Young's modulus, Poisson's ratio, maximum and minimum principal stresses, and vertical stress data to establish a geomechanical model of the single-well reservoir. Figure 2 , 3 As shown, the matrix geological model of the reservoir where the single well is located and the geomechanical model of the single well reservoir are confirmed. Figure 2 The matrix geological model in the text is a matrix geological model based on porosity. Figure 3 The geomechanical model in the text is a geomechanical model based on Poisson's ratio.

[0110] For example Figure 4 As shown, based on the geomechanical model, the fracture propagation trajectory after the initial fracturing is calculated according to the perforation location and pumping procedure. The simulation can be performed using complex fracture propagation software, and the fracture propagation trajectory after the initial fracturing can be calculated. Using the embedded discrete fracture method, the fracture propagation trajectory after the initial fracturing is discretized into several fracture segments, resulting in a fracture network. This network includes fractures and fracture segments. The fracture network is converted into a natural fracture format, and a natural fracture mesh is generated based on the converted network to determine the fracture propagation result after the initial fracturing. The fracture propagation result after the initial fracturing, i.e., the fracture network converted into a natural fracture format, is embedded into the structured numerical simulation model mesh. Together with the reservoir matrix network, it forms an unstructured mesh, thus coupling the fracture propagation result after the initial fracturing to the matrix geological model and determining the fracture propagation model after the initial fracturing. Figure 5 As shown, the primary fracturing fracture propagation model includes a natural fracture mesh and a raw matrix fracture mesh; this is used to generate the primary fracturing fracture propagation model.

[0111] By interfacing with external software, manual adjustments, or other methods commonly used in the field, reservoir numerical simulation software or other reservoir numerical simulation software is employed. A dual-pore, dual-permeability black oil model is used to set the relative permeability curves, high-temperature, high-pressure PVT data, and initial parameters for model calculations for the target reservoir. The initial fracturing fracture propagation model is divided into zones: natural fracture mesh is divided into zone I, and the original matrix fracture mesh is divided into zone II. Based on the initial parameters and the initial fracturing fracture propagation model, the initial production of a single well is simulated for ten years, and the average production rate of the first well during initial production is determined. Production curves for zone I and zone II are generated based on the average production rate of the first well during initial production. Analysis is performed to generate the relationship curve between the initial fracturing single well production over ten years, thus determining the initial production model for a single well. Figure 6 As shown, the gray dashed line represents the production of the initial fracturing fracture (Section I), the orange dashed line represents the production of the matrix (Section II), and the blue solid line represents the total production of the initial fracturing fracture (Section I) and the matrix (Section II). The initial fracturing fracture propagation model changes accordingly after a single well is put into production. The single-well initial production model is a geological model simulating the initial fracturing fracture propagation model ten years after production.

[0112] Based on the initial production model of a single well, and according to the perforation location and pumping procedure of repeated fracturing, the fracture propagation trajectory after repeated fracturing is calculated. This can be simulated using complex fracture propagation software, and the fracture propagation trajectory after repeated fracturing is calculated. Using the embedded discrete fracture method, the fracture propagation trajectory of repeated fracturing is discretized into several fracture segments, generating an artificial fracture mesh for repeated fracturing, and the fracture propagation result is determined. The fracture propagation result of repeated fracturing is coupled to the initial production model of a single well using the embedded discrete fracture method to generate a repeated fracturing fracture propagation model. This model includes a natural fracture mesh, a primary matrix fracture mesh, and an artificial fracture mesh for repeated fracturing.

[0113] The repeated fracturing fracture propagation model was partitioned into three zones: zone III for artificial fractures, zone IV for natural fractures, and zone V for the original matrix fractures. Based on initial parameters, a single well was simulated for ten years of repeated fracturing production using the model, and the average well production rate was determined. Production curves for zones III, IV, and V were generated based on the average well production rate and analyzed to produce a ten-year relationship curve for the production rate of repeatedly fracturing wells. Figure 7 As shown, the gray solid line represents the production of repeated fracturing fractures (Section III), the yellow solid line represents the production of primary fracturing fractures (Section IV), the orange solid line represents the production of the matrix (Section V), and the blue solid line represents the total production of repeated fracturing fractures (Section III), primary fracturing fractures (Section IV), and matrix (Section V).

[0114] Continue to refer to Figure 6 , 7 The contribution rate of single-well production is quantitatively evaluated based on the production relationship curves of single wells after initial fracturing and those after repeated fracturing. The specific analysis method is as follows:

[0115] Based on the initial fracturing single-well production relationship curve, the percentage ratio of the production of Zone I within ten years to the total production of Zones I and II within ten years was calculated, and the result was 70.5%.

[0116] Based on the production relationship curve of a single well subjected to repeated fracturing, the percentage ratio of the production of zone III over ten years to the total production of zones III, IV and V over ten years was calculated, and the result was 35.4%.

[0117] Based on the production relationship curve of a single well subjected to repeated fracturing, the percentage ratio of the production of zone IV over ten years to the total production of zones III, IV and V over ten years was calculated, and the result was 60.35%.

[0118] Based on the calculated three ratios, a quantitative evaluation of the single-well production contribution rate is completed. On this basis, the effect of repeated fracturing of old oil wells is evaluated, and the fracturing parameters of oil wells are optimized.

[0119] Secondly, based on the same inventive concept, the present disclosure also provides a system for evaluating the contribution rate of fractures to single-well production, including: a single-well model establishment module, a single-well fracture propagation module, a single-well production analysis module, and a single-well contribution analysis module.

[0120] The single-well model building module is used to build a matrix geological model of the reservoir where the target single well is located, and to determine the geomechanical model of the single-well reservoir based on the matrix geological model.

[0121] The single-well fracture propagation module is used to determine the initial fracturing fracture propagation results based on the geomechanical model, and couple the initial fracturing fracture propagation results to the matrix geological model to generate the initial fracturing fracture propagation model; based on the single-well initial production model, the repeated fracturing fracture propagation results are determined, and the repeated fracturing fracture propagation results are coupled to the single-well initial production model to obtain the repeated fracturing fracture propagation model.

[0122] The single-well production analysis module is used to simulate the first preset time for the initial production of a single well based on the initial fracturing fracture propagation model, generate the initial fracturing single-well production relationship curve within the first preset time, and determine the single-well initial production model; based on the repeated fracturing fracture propagation model, it simulates the second preset time for the repeated production of a single well, and generates the repeated fracturing single-well production relationship curve within the second preset time.

[0123] The single-well contribution analysis module is used to quantitatively evaluate the production contribution rate of a single well based on the production relationship curves of the first fracturing single well and the production relationship curves of the repeated fracturing single well.

[0124] Thirdly, based on the same inventive concept, the present disclosure also provides a computer-readable storage medium storing one or more programs, which, when executed, can realize the aforementioned method for evaluating the contribution rate of fractures to single-well production.

[0125] Fourthly, based on the same inventive concept, Figure 8 This is a schematic diagram of an electronic device structure provided in an embodiment of the present disclosure, such as... Figure 8As shown in the illustration, this disclosure also provides an electronic device, including a processor, a communication interface, the aforementioned computer-readable storage medium, and a communication bus. The processor, communication interface, and computer-readable storage medium communicate with each other via the communication bus. The processor is used to execute a program stored in the computer-readable storage medium.

[0126] It should be noted that the electrical connection between the above-mentioned units does not necessarily mean the connection between lines. The indirect connection method can be applied to the embodiments of this disclosure as long as it achieves the purpose of this disclosure.

[0127] Although the present disclosure has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features; and such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present disclosure.

Claims

1. A method for evaluating the contribution of fractures to single-well production, characterized in that, The method includes: Establish a matrix geological model of the reservoir where the target well is located, and determine the geomechanical model of the reservoir based on the matrix geological model; Based on the geomechanical model, the initial hydraulic fracturing fracture propagation result is determined, and the initial hydraulic fracturing fracture propagation result is coupled to the matrix geological model to generate the initial hydraulic fracturing fracture propagation model. Based on the initial fracturing fracture propagation model, the first preset time for the initial production of a single well is simulated, and the production relationship curve of the single well during the first preset time is generated to determine the initial production model of the single well. Based on the single-well initial production model, the repeated fracturing fracture propagation results are determined, and the repeated fracturing fracture propagation results are coupled to the single-well initial production model to obtain the repeated fracturing fracture propagation model. Based on the repeated fracturing fracture propagation model, a second preset duration of repeated production of a single well is simulated, and a production relationship curve of a single well during the second preset duration of repeated fracturing is generated. The contribution rate of single-well production is quantitatively evaluated based on the production relationship curves of the first fracturing single well and the repeated fracturing single well.

2. The method according to claim 1, characterized in that, Establish a matrix geological model of the reservoir where the target well is located, and determine the geomechanical model of the reservoir based on the matrix geological model, including: Acquire well point stratification data, sedimentary microfacies data, multi-well logging data, and single-well logging data for the target single well; Using the well point stratification data, an initial structural model is determined; based on the initial structural model and the sedimentary microfacies data, a facies model is established. Based on the phase model, an attribute model is established according to the multi-well logging data, and the matrix geological model of the reservoir where the target well is located is determined. Based on the matrix geological model, Young's modulus, Poisson's ratio, maximum and minimum principal stresses, and vertical stress data are calculated using the single-well logging data to establish the geomechanical model of the single-well reservoir.

3. The method according to claim 1, characterized in that, Based on the geomechanical model, the initial hydraulic fracturing fracture propagation results are determined. These results are then coupled to the matrix geological model to generate an initial hydraulic fracturing fracture propagation model, including: Based on the aforementioned geomechanical model, the fracture propagation trajectory of the initial fracturing is calculated according to the initial fracturing perforation location and pumping procedure. Based on the fracture propagation trajectory of the initial fracturing, the fracture is discretized into multiple fracture segments, and a natural fracture mesh is generated to determine the fracture propagation result of the initial fracturing. The initial hydraulic fracturing fracture propagation results are coupled to the matrix geological model to generate the initial hydraulic fracturing fracture propagation model; wherein, the initial hydraulic fracturing fracture propagation model includes the natural fracture grid and the original matrix fracture grid.

4. The method according to claim 1, characterized in that, Based on the initial fracturing fracture propagation model, the first preset time for initial production of a single well is simulated, generating the initial fracturing single-well production relationship curve within the first preset time, and determining the single-well initial production model, including... A dual-pore dual-permeability black oil model was adopted, and the relative permeability curves of the target reservoir, high-temperature and high-pressure PVT data, and initial parameters for model calculation were set. The initial fracturing fracture propagation model is divided into partitions: the natural fracture mesh is divided into partition I, and the original matrix fracture mesh is divided into partition II. Based on the initial parameters and the initial fracturing fracture propagation model, the first preset time for the initial production of a single well is simulated, and the average production rate of the single well during the initial production is determined. The production curves for Zone I and Zone II are generated based on the average single-well production during the initial production period, and the production relationship curve of the single well during the initial fracturing within the first preset time period is obtained to determine the single-well initial production model.

5. The method according to claim 1, characterized in that, Based on the initial production model of a single well, the propagation results of repeated fracturing are determined. These results are then coupled back to the initial production model of the single well to obtain the repeated fracturing propagation model, which includes: Based on the single-well initial production model, the fracture propagation trajectory of repeated fracturing is calculated according to the perforation location and pumping procedure of repeated fracturing. Based on the fracture propagation trajectory of repeated fracturing, the fracture is discretized into multiple fracture segments, and an artificial fracture mesh of repeated fracturing is generated to determine the fracture propagation result of repeated fracturing. The repeated fracturing fracture propagation results are coupled to the single-well initial production model to generate a repeated fracturing fracture propagation model; wherein, the repeated fracturing fracture propagation model includes a natural fracture grid, an original matrix fracture grid, and the repeated fracturing artificial fracture grid.

6. The method according to claim 1, characterized in that, Based on the repeated fracturing fracture propagation model, a second preset production duration for repeated production in a single well is simulated, generating a production relationship curve for the repeated fracturing single well within the second preset duration, including: The repeated fracturing fracture propagation model is divided into partitions: the repeated fracturing artificial fracture mesh is divided into partition III, the natural fracture mesh is divided into partition IV, and the original matrix fracture mesh is divided into partition V. Based on the initial parameters and the repeated fracturing fracture propagation model, the second preset duration of repeated production of a single well is simulated, and the average production per well during repeated production is determined. The production curves for zones III, IV, and V are generated based on the average production of a single well during repeated production, and the production relationship curve of a single well during repeated fracturing within the second preset time period is obtained.

7. The method according to claim 1, characterized in that, The contribution rate of single-well production is quantitatively evaluated based on the production relationship curves of single wells after initial fracturing and those after repeated fracturing, including: Based on the initial fracturing single-well production relationship curve, calculate the ratio of the production of zone I within the first preset time period to the total production of zone I and zone II within the first preset time period; Based on the repeated fracturing single-well production relationship curve, calculate the ratio of the production of zone III within the second preset time period to the total production of zones III, IV, and V within the second preset time period; based on the repeated fracturing single-well production relationship curve, calculate the ratio of the production of zone IV within the second preset time period to the total production of zones III, IV, and V within the second preset time period.

8. A system for evaluating the contribution of fractures to single-well production, characterized in that, The system includes: a single-well model establishment module, a single-well fracture propagation module, a single-well production analysis module, and a single-well contribution analysis module; The single-well model establishment module is used to establish a matrix geological model of the reservoir where the target single well is located, and to determine the geomechanical model of the single-well reservoir based on the matrix geological model. The single-well fracture propagation module is used to determine the initial fracturing fracture propagation result based on the geomechanical model, couple the initial fracturing fracture propagation result to the matrix geological model to generate the initial fracturing fracture propagation model; and determine the repeated fracturing fracture propagation result based on the single-well initial production model, couple the repeated fracturing fracture propagation result to the single-well initial production model to obtain the repeated fracturing fracture propagation model. The single-well production analysis module is used to simulate the first preset time for the initial production of a single well based on the initial fracturing fracture propagation model, generate the initial fracturing single-well production relationship curve within the first preset time, and determine the single-well initial production model; and to simulate the second preset time for repeated production of a single well based on the repeated fracturing fracture propagation model, generate the repeated fracturing single-well production relationship curve within the second preset time. The single-well contribution analysis module is used to quantitatively evaluate the production contribution rate of a single well based on the production relationship curve of the first fracturing single well and the production relationship curve of the repeated fracturing single well.

9. A computer-readable storage medium storing one or more programs, characterized in that, When one or more of these programs are executed, the method for evaluating the contribution rate of fractures to single-well production as described in any one of claims 1-7 can be implemented.

10. An electronic device, comprising a processor, a communication interface, a computer-readable storage medium as described in claim 9, and a communication bus; wherein, The processor, communication interface, and computer-readable storage medium communicate with each other via a communication bus; Its features are, The processor is used to execute programs stored in a computer-readable storage medium.

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