A shale gas horizontal well design and fracturing scheme optimization method and system

Abstract

A method and system for optimizing the design and fracturing scheme of shale gas horizontal wells, belonging to the field of oil and gas field development, includes: multi-source data collection and preprocessing; multi-source data fusion to generate a high-precision three-dimensional geological model; establishing reservoir attribute models and natural fracture models respectively, and predicting the activity of natural fractures; evaluation of geological engineering parameters, evaluation of vertical and horizontal sweet spots, and well location deployment; drilling / fracturing geological design; fracturing site tracking and post-fracturing production effect evaluation; using numerical simulation technology to predict the degree of shale gas horizontal well stimulation and gas well productivity, and continuously adjusting and optimizing the shale gas horizontal well design and fracturing optimization scheme based on the prediction results and feedback from actual production data. This invention has the advantages of high accuracy and reliability in reservoir evaluation, while reducing construction risks and improving development results; it also improves the productivity and economic benefits of shale gas horizontal wells.

Description

Technical Field

[0001] This invention belongs to the field of oil and gas field development technology, specifically relating to a method and system for optimizing the design and fracturing scheme of shale gas horizontal wells. Background Technology

[0002] Currently, active exploration and development of shale gas have been carried out in the Sichuan Basin, achieving significant results through continuous exploration and practice. The Sichuan Basin has become a major shale gas development area in China. As an important guarantee for increasing natural gas reserves and production, shale gas development has shown enormous potential. However, shale gas reservoirs have complex geological conditions, strong reservoir heterogeneity, numerous microstructures and microfractures, and frequent engineering accidents. During development, the difference in test production between platform wells can reach 80%, and the annual rate of well switching can reach as high as 60%. How to optimize the design according to geological characteristics to reduce engineering construction risks is a technical challenge restricting the efficient development of shale gas. Summary of the Invention

[0003] To address the challenges of reservoir heterogeneity, engineering construction risks, and varying production outcomes in shale gas reservoirs, this invention provides a method and system for optimizing the design and fracturing schemes of shale gas horizontal wells. The method and system are primarily used to optimize the design and fracturing schemes of horizontal wells during the construction of unconventional shale gas horizontal wells, and can be applied to geological evaluation and engineering risk prediction.

[0004] The technical solution adopted by this invention to solve the technical problem is as follows:

[0005] This invention provides a method for optimizing the design and fracturing scheme of shale gas horizontal wells, which mainly includes the following steps:

[0006] Step S1: Multi-source data collection and preprocessing;

[0007] Step S2: Multi-source data fusion to generate a high-precision three-dimensional geological model;

[0008] Step S3: Establish reservoir property models and natural fracture models respectively, and predict the activity of natural fractures;

[0009] Step S4: Evaluation of geological engineering parameters, evaluation of vertical and horizontal sweet spots, and well location deployment;

[0010] Step S5: Drilling / fracking geological design;

[0011] Step S6: On-site tracking of fracturing and evaluation of post-fracturing production effects;

[0012] Step S7: Use numerical simulation technology to predict the degree of shale gas horizontal well stimulation and well production capacity. Based on the prediction results and feedback from actual production data, continuously adjust and optimize the shale gas horizontal well design and fracturing optimization scheme.

[0013] Furthermore, the multi-source data includes seismic data, well logging curve data, well logging data, core analysis data, test data, actual drilling data, actual fracturing data, and production data; the preprocessing includes data cleaning, data correction, and data alignment.

[0014] Furthermore, in step S2, the multi-source data collected by the present invention are fused using a three-dimensional geological model to generate a high-precision three-dimensional geological model, namely a fine structural model.

[0015] Furthermore, in step S3, the method for establishing the reservoir attribute model is as follows: applying a high-precision three-dimensional geological model and a geomechanical model to finely characterize the reservoir features, establishing the reservoir attribute model, and generating a reservoir attribute distribution map.

[0016] The method for establishing the natural fracture model is as follows: based on geostatistical analysis and numerical simulation technology, the fracture development law is analyzed, and a natural fracture model, namely a three-dimensional fracture network model, is constructed.

[0017] The method for predicting the activity of natural fractures is as follows: by applying actual hydraulic fracturing construction data and geostress data, the activity of natural fractures is specifically analyzed, and the activity state of natural fractures is predicted, thereby obtaining the prediction results of natural fracture activity.

[0018] Furthermore, the specific implementation process of step S4 is as follows:

[0019] Step S4.1: Evaluation of geological engineering parameters;

[0020] Multi-source data fusion of seismic, well logging, well logging, and core data is carried out, and geostatistical methods are used to analyze the spatial distribution of reservoir thickness, gas content, brittle minerals, natural fractures, and geomechanical characteristic parameters. The impact of each parameter on production capacity is quantified based on actual production results, thereby determining the main controlling factors.

[0021] Step S4.2: Evaluation of desserts both horizontally and vertically;

[0022] Based on well logging and seismic data, transverse sweet spot regions of the reservoir are identified in step S4.1; based on the detailed reservoir evaluation, key reservoir parameters are evaluated according to production performance and drilling and fracturing parameters to determine the location of vertical sweet spots.

[0023] Step S4.3: Well location deployment;

[0024] Based on reservoir quality, natural fracture development, and principal stress direction data, the well location and well trajectory orientation were initially determined. The horizontal section length and well spacing parameters were determined using numerical simulation methods and actual drilling production data. At the same time, the well location deployment plan was optimized by considering economic factors and risks.

[0025] Furthermore, the specific implementation process of step S5 is as follows:

[0026] Step S5.1: Horizontal well trajectory optimization design;

[0027] Based on a high-precision three-dimensional geological model and a three-dimensional fracture network model, the optimal horizontal well trajectory is designed;

[0028] Step S5.2: Geological steering of the horizontal well;

[0029] Implement a horizontal well geological steering process, and simultaneously correct the fine structural model based on the actual drilling trajectory;

[0030] Step S5.3: Optimization of geological design for horizontal well fracturing;

[0031] Determine the key parameters of the fracturing scheme, and then determine the fracturing scheme; carry out fracturing operations based on the optimal horizontal well trajectory and the fracturing scheme.

[0032] Furthermore, in step S5.3, the key parameters include: segment length, number of clusters, nesting variation, and risk prevention and control measures for crosstalk.

[0033] Furthermore, the specific implementation process of step S6 is as follows:

[0034] Step S6.1: On-site tracking of fracturing;

[0035] Real-time monitoring and tracking of fracturing site conditions; utilizing real-time fracturing construction curves, pumping perforation parameters, pressure changes in adjacent wells, and real-time microseismic monitoring data; conducting integrated geological and engineering analysis and diagnosis for abnormal situations; and optimizing and adjusting the cluster parameters, temporary plugging timing, and dosage for this section and subsequent construction sections.

[0036] Step S6.2: Evaluation of post-pressing production effect;

[0037] Based on actual production conditions, fracturing simulation results, and fiber optic monitoring data, the artificial fracture propagation characteristics and conductivity are evaluated. By comparing reservoir conditions and construction parameters, the fracturing design parameters are further optimized.

[0038] Furthermore, in step S7, the geological engineering evaluation parameters, longitudinal and transverse sweet spot evaluation parameters, and well location deployment plan are continuously adjusted and optimized based on the drilling conditions and fracturing operation results; at the same time, the horizontal well fracturing geological design plan is continuously adjusted and optimized based on the fracturing site construction and fracturing operation results.

[0039] This invention provides a shale gas horizontal well design and fracturing scheme optimization system. This system is used to implement the aforementioned shale gas horizontal well design and fracturing scheme optimization method. The system includes:

[0040] Multi-source data acquisition module, used to collect data from multiple data sources;

[0041] The multi-source data preprocessing module is used to preprocess the collected data from multiple data sources;

[0042] The multi-source data fusion module is used to receive preprocessed multi-source data from the multi-source data acquisition and preprocessing module, and to fuse the received multi-source data to generate a high-precision three-dimensional geological model.

[0043] The geological engineering parameter characterization module includes a reservoir attribute model construction module, a natural fracture model construction module, and a natural fracture activity prediction module. The reservoir attribute model construction module is used to establish reservoir attribute models: applying high-precision 3D geological models and geomechanical models to finely characterize reservoir features, establish reservoir attribute models, and then generate reservoir attribute distribution maps. The natural fracture model construction module is used to establish natural fracture models: based on geostatistical analysis and numerical simulation technology, it analyzes fracture development patterns and constructs natural fracture models, i.e., 3D fracture network models. The natural fracture activity prediction module is used to predict natural fracture activity: applying actual hydraulic fracturing construction data and geostress data, it specifically analyzes natural fracture activity, predicts the activity state of natural fractures, and then obtains natural fracture activity prediction results.

[0044] The geological evaluation and well location deployment module is used to evaluate geological engineering parameters, evaluate vertical and horizontal sweet spots, and deploy well locations.

[0045] The drilling / fracking geological design module includes a horizontal well trajectory optimization design module, a horizontal well geological steering module, and a horizontal well fracturing geological design optimization module. The horizontal well trajectory optimization design module designs the optimal horizontal well trajectory based on a high-precision 3D geological model and a 3D fracture network model. The horizontal well geological steering module implements the horizontal well geological steering process and simultaneously corrects the fine structural model based on the actual drilling trajectory. The horizontal well fracturing geological design optimization module determines the key parameters of the fracturing scheme, thereby determining the fracturing scheme. Fracturing operations are then carried out based on the optimal horizontal well trajectory and the fracturing scheme.

[0046] The tracking and evaluation module is used to track fracturing operations on-site and evaluate post-fracturing production effects.

[0047] The design optimization and adjustment module is used to predict the degree of shale gas horizontal well stimulation and well production capacity using numerical simulation software. Based on the prediction results and feedback from actual production data, the module continuously adjusts and optimizes the shale gas horizontal well design and fracturing optimization scheme.

[0048] The beneficial effects of this invention are:

[0049] To address the problems existing in current technologies, this invention proposes a method and system for optimizing the design and fracturing schemes of shale gas horizontal wells based on multi-source data fusion and fine characterization, fracture development law research, and engineering application method optimization. This allows for the optimization of horizontal well design and fracturing schemes during the construction of unconventional shale gas horizontal wells and can be used for geological evaluation and engineering risk prediction. Compared with existing technologies, this invention has the following advantages:

[0050] 1. High accuracy and reliability in reservoir evaluation;

[0051] This invention employs multi-source data fusion processing technology, applying a multi-source data fusion method of seismic, well logging, and engineering construction parameters to form more comprehensive and accurate reservoir evaluation data. Based on multi-source data fusion, this invention also utilizes fine characterization technology to provide a detailed description of multiple characteristics of the reservoir, such as lithology, physical properties, and gas content, thereby comprehensively improving the accuracy and reliability of reservoir evaluation.

[0052] 2. Reduce construction risks and improve development results;

[0053] This invention comprehensively utilizes geostatistical methods and numerical simulation technology to complete geological evaluation, applies actual data to conduct fracture activity analysis, and conducts in-depth research on the development law and distribution characteristics of fractures. By comparing and analyzing the fracture development under different geological conditions, it reveals the intrinsic relationship between fractures and reservoir properties, structural characteristics, and other factors. The comprehensive evaluation results are used for engineering risk prediction and design optimization, providing a scientific basis for horizontal well trajectory design and fracturing scheme optimization, reducing construction risks, and ensuring development results.

[0054] 3. Improved productivity and economic benefits of shale gas horizontal wells;

[0055] This invention ensures that the wellbore can traverse more high-quality reservoirs and fractured zones by rationally designing the horizontal well trajectory; at the same time, it optimizes the fracturing scheme based on the development characteristics and distribution patterns of fractures, thereby improving the fracturing effect and thus increasing the productivity and economic benefits of shale gas horizontal wells. Attached Figure Description

[0056] Figure 1 This is a flowchart illustrating an optimization method for shale gas horizontal well design and fracturing schemes based on multi-source data fusion and fine characterization, fracture development law research, and engineering application method optimization, according to the present invention.

[0057] Figure 2 This is a structural block diagram of a shale gas horizontal well design and fracturing scheme optimization system based on multi-source data fusion and fine characterization, fracture development law research, and engineering application method optimization, according to the present invention. Detailed Implementation

[0058] The present invention will be further described in detail below with reference to the accompanying drawings.

[0059] To address the issues of strong reservoir heterogeneity in shale gas reservoirs, frequent well leakage and casing deformation accidents, and large differences in production among wells, this invention proposes a method and system for optimizing the design and fracturing scheme of shale gas horizontal wells based on multi-source data fusion and fine characterization, fracture development law research, and engineering application method optimization.

[0060] In a first aspect, the present invention provides a method for optimizing the design and fracturing scheme of shale gas horizontal wells.

[0061] The present invention provides a method for optimizing the design and fracturing scheme of shale gas horizontal wells, which specifically includes the following:

[0062] ① Multi-source data fusion and detailed characterization;

[0063] This invention employs multi-source data fusion processing technology to integrate multiple data sources, such as geological, geophysical, and geochemical data, to form more comprehensive and accurate reservoir evaluation data.

[0064] Based on this, the lithology, physical properties, gas content and other characteristics of the reservoir are described in detail using fine characterization technology, which improves the accuracy and reliability of reservoir evaluation.

[0065] ② Study on the development pattern of cracks;

[0066] This invention utilizes geostatistical methods and numerical simulation techniques to conduct an in-depth study of the development patterns and distribution characteristics of fractures. By comparing and analyzing fracture development under different geological conditions, the intrinsic relationship between fractures and reservoir properties, structural characteristics, and other factors is revealed, providing a scientific basis for horizontal well trajectory design and fracturing scheme optimization.

[0067] ③ Optimization of engineering application methods;

[0068] Based on the aforementioned reservoir evaluation and fracture development studies, this invention optimizes the horizontal well trajectory design and fracturing scheme. By rationally designing the horizontal well trajectory, it ensures that the wellbore can traverse more high-quality reservoirs and fractured zones. Simultaneously, this invention optimizes the fracturing scheme according to the development characteristics and distribution patterns of fractures, improving fracturing effectiveness and thus increasing the productivity and economic benefits of shale gas horizontal wells.

[0069] See Figure 1 This invention provides a detailed description of a method for optimizing the design and fracturing scheme of shale gas horizontal wells.

[0070] The present invention provides a method for optimizing the design and fracturing scheme of shale gas horizontal wells, the specific implementation process of which is as follows:

[0071] Step S1: Multi-source data collection and preprocessing;

[0072] Collect multi-source data from different channels and preprocess the multi-source data;

[0073] The multi-source data collected in this invention includes, but is not limited to, seismic data, well logging curve data, well logging data, core analysis data, test data, actual drilling data, actual fracturing data, and production data.

[0074] The sources of data such as seismic data, well logging curve data, well logging data, core analysis data, test data, actual drilling data, actual fracturing data, and production data include, but are not limited to, geological data, seismic data, well logging data, well logging data, core data, test data, drilling data, fracturing data, and production data.

[0075] Preprocessing methods include, but are not limited to, data cleaning, data correction, and data alignment.

[0076] Step S2: Multi-source data fusion;

[0077] Currently, existing data fusion methods include, but are not limited to, weighted methods, model combination methods, and data-driven methods. Weighted methods primarily assign weights to different data points to reflect their importance, and then perform weighted fusion processing based on these weights. Model combination methods involve creating separate 3D geological models for different data points, and then combining these models to obtain the final fused 3D geological model. Data-driven methods involve constructing mathematical models, using different data points as inputs, and achieving data fusion through calculation and optimization of the mathematical models. These fusion processing methods can better aid in understanding subsurface structures and reservoir distribution, providing more comprehensive and accurate geological information.

[0078] Therefore, in this invention, a model combination method can be specifically selected to achieve the fusion processing of multi-source data. Specifically, a three-dimensional geological model can be used to fuse the multi-source data collected in this invention, thereby generating a high-precision three-dimensional geological model, which is actually a fine structural model.

[0079] Step S3: Characterization of geological engineering parameters;

[0080] The specific implementation process is as follows:

[0081] Step S3.1: Establish a reservoir attribute model;

[0082] The high-precision three-dimensional geological model and geomechanical model generated in step S2 are used to finely characterize the reservoir features, establish a reservoir attribute model, and then generate a reservoir attribute distribution map.

[0083] Step S3.2: Establish a natural crack model;

[0084] Based on geostatistical analysis and numerical simulation technology, the development law of fractures is analyzed, and a natural fracture model, namely a three-dimensional fracture network model, is constructed.

[0085] Step S3.4: Predict the activity of natural fissures;

[0086] By applying actual fracturing construction data and geostress data, the activity of natural fractures is specifically analyzed. By predicting the activity state of natural fractures, the prediction results of natural fracture activity are obtained.

[0087] Step S4: Geological assessment and well location deployment;

[0088] The specific implementation process is as follows:

[0089] Step S4.1: Evaluation of geological engineering parameters;

[0090] Multi-source data fusion of seismic, well logging, well logging, and core data is carried out, and geostatistical methods are used to analyze the spatial distribution of parameters such as reservoir thickness, gas content, brittle minerals, natural fractures, and geomechanical characteristics. The impact of each parameter on production capacity is quantified based on actual production results, thereby determining the main controlling factors.

[0091] Step S4.2: Evaluation of desserts both horizontally and vertically;

[0092] Based on the understanding gained in step S4.1, transverse sweet spots in the reservoir are identified using well logging and seismic data. Following a detailed reservoir evaluation, key reservoir parameters are assessed based on production performance and drilling / fracturing parameters to determine the location of vertical sweet spots.

[0093] Step S4.3: Well location deployment;

[0094] Based on data such as reservoir quality, natural fracture development, and principal stress direction, the well location and well trajectory orientation are initially determined. Numerical simulation methods and actual drilling production data are used to determine parameters such as horizontal section length and well spacing. Simultaneously, considering economic factors and risks, the well location deployment plan is optimized.

[0095] Step S5: Drilling / fracking geological design;

[0096] Drilling / fracking geological design mainly includes: horizontal well trajectory optimization design, horizontal well geological steering, and horizontal well fracturing geological design optimization; its specific implementation process is as follows:

[0097] Step S5.1: Horizontal well trajectory optimization design;

[0098] Based on the high-precision three-dimensional geological model generated in step S2 and the three-dimensional fracture network model constructed in step S4, the optimal horizontal well trajectory is designed.

[0099] Step S5.2: Geological steering of the horizontal well;

[0100] Implement a horizontal well geological steering process, and simultaneously correct the fine structural model based on the actual drilling trajectory.

[0101] Step S5.3: Optimization of geological design for horizontal well fracturing;

[0102] Determine the key parameters of the fracturing scheme, including segment length, number of clusters, casing deformation, and measures to prevent and control the risk of fracturing cross-flow, and then determine the fracturing scheme; carry out fracturing construction based on the optimal fracturing scheme.

[0103] Step S6: Follow-up evaluation;

[0104] The follow-up evaluation mainly includes on-site tracking of fracturing and evaluation of post-fracturing production effects; its specific implementation process is as follows:

[0105] Step S6.1: On-site tracking of fracturing;

[0106] Real-time monitoring and tracking of fracturing site conditions; utilizing real-time fracturing construction curves, pumping perforation parameters, pressure changes in adjacent wells, and microseismic data to conduct integrated geological and engineering analysis and diagnosis for abnormal situations; and optimizing and adjusting the cluster parameters, temporary plugging timing, and dosage for this section and subsequent construction sections.

[0107] Step S6.2: Evaluation of post-pressing production effect;

[0108] Based on actual production conditions, fracturing simulation results, and production logging data such as fiber optic monitoring, the characteristics of artificial fracture distribution and conductivity are evaluated. By comparing reservoir conditions and construction parameters, fracturing design parameters are further optimized.

[0109] Step S7: Adjustment and optimization of the plan;

[0110] Numerical simulation software is used to predict the degree of shale gas horizontal well stimulation and well production capacity. Based on the prediction results and feedback from actual production data, the design and fracturing optimization schemes for shale gas horizontal wells are continuously adjusted and optimized.

[0111] The specific implementation process is as follows:

[0112] Step S7.1: Based on the drilling situation in Step S5.2 and the fracturing operation effect in Step S5.3, continuously adjust and optimize the geological engineering evaluation parameters in Step S4.1, the longitudinal and transverse sweet spot evaluation parameters in Step S4.2, and the well location deployment plan in Step S4.3;

[0113] Step S7.2: Continuously adjust and optimize the horizontal well fracturing geological design scheme based on the fracturing site construction and fracturing results.

[0114] Secondly, the present invention provides a shale gas horizontal well design and fracturing scheme optimization system.

[0115] See Figure 2 As described above, the shale gas horizontal well design and fracturing scheme optimization system of the present invention specifically includes the following modules:

[0116] The system includes a multi-source data acquisition module, a multi-source data preprocessing module, a multi-source data fusion module, a geological engineering parameter characterization module, a geological evaluation and well location deployment module, a drilling / fracture geological design module, a tracking evaluation module, and a design scheme optimization and adjustment module.

[0117] Specifically, the geological engineering parameter characterization module mainly includes: reservoir attribute model construction module, natural fracture model construction module, and natural fracture activity prediction module; the geological evaluation and well location deployment module mainly includes: geological engineering parameter evaluation module, vertical and horizontal sweet spot evaluation module, and well location deployment module; the drilling / fracture geological design module mainly includes: horizontal well trajectory optimization design module, horizontal well geological steering module, and horizontal well fracturing geological design optimization module; the tracking and evaluation module mainly includes fracturing site tracking module and post-fracturing production effect evaluation module.

[0118] The specific functions and roles of each module are as follows:

[0119] The multi-source data acquisition module is primarily used to collect data from multiple data sources. These data sources can originate from geological data, seismic data, well logging data, core data, testing data, drilling data, fracturing data, and production data, but are not limited to these. Specifically, the data sources can include seismic data, well logging curve data, well logging data, core analysis data, testing data, actual drilling data, actual fracturing data, and production data, but are not limited to these.

[0120] The multi-source data preprocessing module is mainly used to perform preprocessing operations such as data cleaning, data correction, or data alignment on the collected data from multiple data sources, so as to facilitate subsequent fusion processing steps.

[0121] The multi-source data fusion module is mainly used to receive preprocessed multi-source data output from the multi-source data acquisition and preprocessing module, and to perform fusion processing on the received multi-source data. The fusion processing method can specifically employ weighted methods, model combination methods, and data-driven methods, but is not limited to these. Preferably, this invention utilizes a three-dimensional geological model to perform fusion processing on the multi-source data collected, thereby generating a high-precision three-dimensional geological model, which is actually a fine structural model.

[0122] The geological engineering parameter characterization module is primarily used to characterize geological engineering parameters. This module mainly includes: a reservoir attribute model construction module, a natural fracture model construction module, and a natural fracture activity prediction module. The reservoir attribute model construction module is used to establish reservoir attribute models: applying high-precision 3D geological models and geomechanical models to finely characterize reservoir features, establish reservoir attribute models, and generate reservoir attribute distribution maps. The natural fracture model construction module is used to establish natural fracture models: based on geostatistical analysis and numerical simulation techniques, it analyzes fracture development patterns and constructs natural fracture models, i.e., 3D fracture network models. The natural fracture activity prediction module is used to predict natural fracture activity: applying actual hydraulic fracturing data and geostress data, it specifically analyzes natural fracture activity, predicts the activity state of natural fractures, and obtains natural fracture activity prediction results.

[0123] The geological evaluation and well location deployment module is mainly used to evaluate geological engineering parameters, evaluate vertical and horizontal sweet spots, and deploy well locations. This geological evaluation and well location deployment module mainly includes: a geological engineering parameter evaluation module, a vertical and horizontal sweet spot evaluation module, and a well location deployment module.

[0124] The drilling / fracking geological design module is primarily used for horizontal well trajectory optimization, horizontal well geological steering, and horizontal well fracturing geological design optimization. This module mainly includes: a horizontal well trajectory optimization design module, a horizontal well geological steering module, and a horizontal well fracturing geological design optimization module. Specifically, the horizontal well trajectory optimization design module is used to design the optimal horizontal well trajectory based on a high-precision 3D geological model and a 3D fracture network model; the horizontal well geological steering module is used to implement the horizontal well geological steering process and simultaneously correct the fine structural model based on the actual drilling trajectory; the horizontal well fracturing geological design optimization module is used to determine the key parameters of the fracturing scheme, thereby determining the fracturing scheme; and fracturing operations are then carried out based on the optimal horizontal well trajectory and fracturing scheme.

[0125] The tracking and evaluation module is mainly used to track fracturing operations on-site and evaluate post-fracturing production effects. This module mainly includes a fracturing on-site tracking module and a post-fracturing production effect evaluation module. The fracturing on-site tracking module is mainly used to monitor and track the fracturing site conditions in real time, formulate optimization and adjustment plans based on complex situations, and ensure the smooth progress of construction. The post-fracturing production effect evaluation module is mainly used to evaluate the distribution morphology of artificial fractures and the suitability of geological conditions and process parameters, laying the foundation for design optimization.

[0126] The design optimization and adjustment module primarily utilizes numerical simulation software to predict the degree of shale gas horizontal well stimulation and well productivity. Based on the prediction results and feedback from actual production data, it continuously adjusts and optimizes the shale gas horizontal well design and fracturing optimization scheme. Specifically, it continuously adjusts and optimizes geological engineering evaluation parameters, vertical and horizontal sweet spot evaluation parameters, and well location deployment schemes based on drilling conditions and fracturing operation results; simultaneously, it continuously adjusts and optimizes the horizontal well fracturing geological design scheme based on on-site fracturing operations and fracturing operation results.

[0127] Using the shale gas horizontal well design and fracturing scheme optimization method and system provided by this invention, drilling geological design work was completed for 26 wells in the Weiyuan shale gas field, geological steering work for 34 wells, and fracturing geological design work for 36 wells. The drilling geological design implementation rate was 100%, the platinum target drilling rate reached over 95%, and the section loss rate was reduced to 0. This invention achieves efficient and precise development of shale gas reservoirs and provides a referable technical path for the development of similar oil and gas fields.

[0128] Those skilled in the art should understand that the above description of the embodiments of the present invention is only intended to illustrate the beneficial effects of the embodiments of the present invention, and is not intended to limit the embodiments of the present invention to any of the examples given.

[0129] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A method for optimizing the design and fracturing scheme of shale gas horizontal wells, characterized in that, Includes the following steps: Step S1: Multi-source data collection and preprocessing; Step S2: Multi-source data fusion to generate a high-precision three-dimensional geological model; Step S3: Establish reservoir property models and natural fracture models respectively, and predict the activity of natural fractures; Step S4: Evaluation of geological engineering parameters, evaluation of vertical and horizontal sweet spots, and well location deployment; Step S5: Drilling / fracking geological design; Step S6: On-site tracking of fracturing and evaluation of post-fracturing production effects; Step S7: Use numerical simulation technology to predict the degree of shale gas horizontal well stimulation and well production capacity. Based on the prediction results and feedback from actual production data, continuously adjust and optimize the shale gas horizontal well design and fracturing optimization scheme.

2. The method for optimizing the design and fracturing scheme of a shale gas horizontal well according to claim 1, characterized in that, The multi-source data includes seismic data, well logging curve data, well logging data, core analysis data, test data, actual drilling data, actual fracturing data, and production data; the preprocessing includes data cleaning, data correction, and data alignment.

3. The method for optimizing the design and fracturing scheme of a shale gas horizontal well according to claim 1, characterized in that, In step S2, the multi-source data collected in this invention are fused using a three-dimensional geological model to generate a high-precision three-dimensional geological model, namely a fine structural model.

4. The method for optimizing the design and fracturing scheme of a shale gas horizontal well according to claim 1, characterized in that, In step S3, the method for establishing the reservoir attribute model is as follows: applying a high-precision three-dimensional geological model and a geomechanical model to finely characterize the reservoir features, establishing the reservoir attribute model, and generating a reservoir attribute distribution map; The method for establishing the natural fracture model is as follows: based on geostatistical analysis and numerical simulation technology, the fracture development law is analyzed, and a natural fracture model, namely a three-dimensional fracture network model, is constructed. The method for predicting the activity of natural fractures is as follows: by applying actual hydraulic fracturing construction data and geostress data, the activity of natural fractures is specifically analyzed, and the activity state of natural fractures is predicted, thereby obtaining the prediction results of natural fracture activity.

5. The method for optimizing the design and fracturing scheme of a shale gas horizontal well according to claim 1, characterized in that, The specific implementation process of step S4 is as follows: Step S4.1: Evaluation of geological engineering parameters; Multi-source data fusion of seismic, well logging, well logging, and core data is carried out, and geostatistical methods are used to analyze the spatial distribution of reservoir thickness, gas content, brittle minerals, natural fractures, and geomechanical characteristic parameters. The impact of each parameter on production capacity is quantified based on actual production results, thereby determining the main controlling factors. Step S4.2: Evaluation of desserts both horizontally and vertically; Based on well logging and seismic data, transverse reservoir sweet spots are identified in step S4.1; Based on the detailed evaluation of the reservoir, the key parameters of the reservoir are evaluated according to the production effect and drilling and fracturing operation parameters, and the vertical sweet spot location is determined. Step S4.3: Well location deployment; Based on reservoir quality, natural fracture development, and principal stress direction data, the well location and well trajectory orientation were initially determined. The horizontal section length and well spacing parameters were determined using numerical simulation methods and actual drilling production data. At the same time, the well location deployment plan was optimized by considering economic factors and risks.

6. The method for optimizing the design and fracturing scheme of a shale gas horizontal well according to claim 1, characterized in that, The specific implementation process of step S5 is as follows: Step S5.1: Horizontal well trajectory optimization design; Based on a high-precision three-dimensional geological model and a three-dimensional fracture network model, the optimal horizontal well trajectory is designed; Step S5.2: Geological steering of the horizontal well; Implement a horizontal well geological steering process, and simultaneously correct the fine structural model based on the actual drilling trajectory; Step S5.3: Optimization of geological design for horizontal well fracturing; Determine the key parameters of the fracturing scheme, and then determine the fracturing scheme; carry out fracturing operations based on the optimal horizontal well trajectory and the fracturing scheme.

7. The method for optimizing the design and fracturing scheme of a shale gas horizontal well according to claim 6, characterized in that, In step S5.3, the key parameters include: segment length, number of clusters, nesting variation, and risk prevention and control measures for cross-contamination.

8. The method for optimizing the design and fracturing scheme of a shale gas horizontal well according to claim 1, characterized in that, The specific implementation process of step S6 is as follows: Step S6.1: On-site tracking of fracturing; Real-time monitoring and tracking of fracturing site conditions; utilizing real-time fracturing construction curves, pumping perforation parameters, pressure changes in adjacent wells, and real-time microseismic monitoring data; conducting integrated geological and engineering analysis and diagnosis for abnormal situations; and optimizing and adjusting the cluster parameters, temporary plugging timing, and dosage for this section and subsequent construction sections. Step S6.2: Evaluation of post-pressing production effect; Based on actual production conditions, fracturing simulation results, and fiber optic monitoring data, the artificial fracture propagation characteristics and conductivity are evaluated. By comparing reservoir conditions and construction parameters, the fracturing design parameters are further optimized.

9. The method for optimizing the design and fracturing scheme of a shale gas horizontal well according to claim 1, characterized in that, In step S7, the geological engineering evaluation parameters, longitudinal and transverse sweet spot evaluation parameters, and well location deployment plan are continuously adjusted and optimized based on the drilling conditions and fracturing operation results; at the same time, the horizontal well fracturing geological design plan is continuously adjusted and optimized based on the fracturing site construction and fracturing operation results.

10. A shale gas horizontal well design and fracturing scheme optimization system, characterized in that, This system is used to implement the shale gas horizontal well design and fracturing scheme optimization method according to any one of claims 1-9, and the system includes: Multi-source data acquisition module, used to collect data from multiple data sources; The multi-source data preprocessing module is used to preprocess the collected data from multiple data sources; The multi-source data fusion module is used to receive preprocessed multi-source data from the multi-source data acquisition and preprocessing module, and to fuse the received multi-source data to generate a high-precision three-dimensional geological model. The geological engineering parameter characterization module includes a reservoir attribute model construction module, a natural fracture model construction module, and a natural fracture activity prediction module. The reservoir attribute model construction module is used to establish reservoir attribute models: applying high-precision 3D geological models and geomechanical models to finely characterize reservoir features, establish reservoir attribute models, and then generate reservoir attribute distribution maps. The natural fracture model construction module is used to establish natural fracture models: based on geostatistical analysis and numerical simulation technology, it analyzes fracture development patterns and constructs natural fracture models, i.e., 3D fracture network models. The natural fracture activity prediction module is used to predict natural fracture activity: applying actual hydraulic fracturing construction data and geostress data, it specifically analyzes natural fracture activity, predicts the activity state of natural fractures, and then obtains natural fracture activity prediction results. The geological evaluation and well location deployment module is used to evaluate geological engineering parameters, evaluate vertical and horizontal sweet spots, and deploy well locations. The drilling / fracking geological design module includes a horizontal well trajectory optimization design module, a horizontal well geological steering module, and a horizontal well fracturing geological design optimization module. The horizontal well trajectory optimization design module designs the optimal horizontal well trajectory based on a high-precision 3D geological model and a 3D fracture network model. The horizontal well geological steering module implements the horizontal well geological steering process and simultaneously corrects the fine structural model based on the actual drilling trajectory. The horizontal well fracturing geological design optimization module determines the key parameters of the fracturing scheme, thereby determining the fracturing scheme. Fracturing operations are then carried out based on the optimal horizontal well trajectory and the fracturing scheme. The tracking and evaluation module is used to track fracturing operations on-site and evaluate post-fracturing production effects. The design optimization and adjustment module is used to predict the degree of shale gas horizontal well stimulation and well production capacity using numerical simulation software. Based on the prediction results and feedback from actual production data, the module continuously adjusts and optimizes the shale gas horizontal well design and fracturing optimization scheme.

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