Seismic evaluation method and apparatus for fault stability

Abstract

This invention provides a seismic assessment method and apparatus for fault stability, belonging to the field of seismic exploration technology for oil and gas. The method includes: acquiring basic seismic data for the drilling section; interpreting the faults based on actual drilling data to identify the locations of fault development within the drilling section; extracting seismic attributes that can predict the faults based on the seismic data; determining sensitive attribute bodies, quantitative fault characterization results, geostress prediction results, and geostress direction prediction results; and, based on the Mohr-Coulomb theory, calculating the shear stress and effective normal stress of the fault surface by combining the quantitative fault characterization results with the geostress prediction results and geostress direction prediction results, and obtaining a fault stability prediction planar map based on the shear stress and effective normal stress of the fault surface. This method utilizes seismic fault and geostress field prediction results to calculate the shear stress and effective normal stress of the fault surface to assess the fault stability state, enabling a quantitative assessment of fault stability.

Description

Technical Field

[0001] This invention relates to the field of seismic exploration technology for oil and gas, specifically to a seismic assessment method for fault stability, a seismic assessment device for fault stability, a machine-readable storage medium, and a processor. Background Technology

[0002] In unconventional exploration and development, casing deformation is a significant factor limiting large-scale, efficient development. Currently, casing deformation is commonly observed during the drilling and fracturing stages of shale gas exploration and development. Many factors contribute to casing deformation, including temperature, asymmetric fracturing, cementing quality, and fracture slip. Current research on casing deformation caused by fault slip primarily focuses on single-wellbore analysis, including cementing stages, casing load, cement sheath, and in-situ stress analysis. Multi-stage fracturing numerical models are established to calculate in-situ stress changes near the wellbore. However, research on the mechanical stability of the fracture itself is lacking. The distribution of subsurface stress, the spatial angle between the maximum principal stress and the fracture surface, and the relationship between fracture surface friction and shear stress are all important factors affecting the mechanical stability of the fracture.

[0003] Existing geophysical prediction methods include: (1) prediction of faults at different scales, using post-stack data to extract coherence, curvature, texture, symmetry, ant-like volume, maximum likelihood properties and other qualitative predictions; (2) geostress earthquake prediction, using pre-stack inversion of P-wave impedance, S-wave impedance, density and P-wave / S-wave velocity ratio, and then calculating rock mechanical parameters such as Young's modulus, Poisson's ratio, brittleness index and other parameters.

[0004] However, existing geophysical prediction methods cannot quantitatively assess the stability of faults, making it difficult to guide well placement and avoid drilling risks. Summary of the Invention

[0005] The purpose of this application is to provide a seismic assessment method and apparatus for fault stability, which can quantitatively assess the stability of faults to guide well location deployment and avoid drilling risks.

[0006] To achieve the above objectives, the first aspect of this application provides a seismic assessment method for fault stability, the method comprising:

[0007] Obtain basic seismic data for the drilling section; wherein, the basic seismic data for the drilling section includes seismic data and actual drilling data;

[0008] Based on the actual drilling data, fracture interpretation was performed to identify the location of fracture development in the drilling section.

[0009] Based on the earthquake data, earthquake attributes that can predict faults are extracted;

[0010] The location of the fracture development in the drilling section and the seismic attributes are calibrated to determine the sensitive attribute volume, and the quantitative characterization results of the fracture are determined based on the sensitive attribute volume.

[0011] Based on the seismic data, elastic parameters are inverted to obtain the elastic parameter volume, and the rock mechanics parameter volume is determined based on the elastic parameter volume.

[0012] Based on the elastic parameter body and the rock mechanics parameter body, the geostress prediction results are determined;

[0013] Based on thin plate theory, using rock mechanics parameters, a geological, mechanical and mathematical model is established, and the three-dimensional finite element difference simulation method is used to determine the predicted results of the geostress direction.

[0014] Based on the Mohr-Coulomb theory, and combined with the results of quantitative fracture characterization and geostress prediction, the shear stress and effective normal stress of the fracture surface are calculated, and a fracture stability prediction planar diagram is obtained based on the shear stress and effective normal stress of the fracture surface.

[0015] Optionally, based on the actual drilling data, fracture interpretation is performed to identify the location of fracture development in the drilling section, including:

[0016] The location of fracture development in the drilling section was interpreted using actual drilling engineering recovery maps, FMI imaging logging data, conventional logging data, horizontal section logging data, and microseismic monitoring data.

[0017] Optionally, the seismic data includes pre-stack time-domain migration gathers; the step of performing elastic parameter inversion based on the seismic data to obtain the elastic parameter volume includes:

[0018] Elastic parameters are inverted using pre-stack migration gathers in the time domain to obtain the elastic parameter volume.

[0019] Optionally, the geostress prediction results include overlying formation pressure; the method includes:

[0020] Based on the elastic parameter body and the rock mechanics parameter body, the normal compaction curve of density is calculated using the seismic travel time equation;

[0021] A density curve is created using the normal compaction curve of density and the actual measured density curve.

[0022] The pressure of the overlying strata is calculated by integrating the density curve.

[0023] Optionally, the geostress prediction results also include formation pore pressure; the method includes:

[0024] Based on the elastic parameter body and the rock mechanics parameter body, formation pore pressure is calculated using Eaton's empirical formula.

[0025] Optionally, the geostress prediction results further include horizontal principal stresses; the method includes:

[0026] Based on the elastic parameter body and the rock mechanics parameter body, the horizontal principal stress is calculated using the Huang model.

[0027] Optionally, a fracture stability prediction planar diagram is obtained based on the shear stress and effective normal stress on the fracture surface, including:

[0028] The magnitudes of the shear stress and the effective normal stress on the fracture surface are compared to obtain the comparison results; a fracture stability prediction planar diagram is drawn based on the comparison results.

[0029] A second aspect of this application provides a seismic assessment device for fault stability, the device comprising:

[0030] The basic data acquisition module is used to acquire basic seismic data for the drilling section; wherein, the basic seismic data for the drilling section includes seismic data and actual drilling data;

[0031] The fracture interpretation module is used to interpret fractures based on the actual drilling data and identify the location of fracture development in the drilling section.

[0032] The earthquake attribute extraction module is used to extract earthquake attributes that can predict faults based on the earthquake data.

[0033] The calibration module is used to calibrate the location of the fracture development in the drilling section and the seismic attributes, determine the sensitive attribute volume, and determine the quantitative characterization result of the fracture based on the sensitive attribute volume.

[0034] The inversion module is used to perform elastic parameter inversion based on the seismic data, obtain the elastic parameter volume, and determine the rock mechanics parameter volume based on the elastic parameter volume.

[0035] The geostress prediction module is used to determine the geostress prediction result based on the elastic parameter body and the rock mechanics parameter body;

[0036] The geostress direction prediction module is used to establish geological, mechanical and mathematical models based on thin plate theory and rock mechanics parameters, and to determine the geostress direction prediction results using three-dimensional finite element difference simulation method.

[0037] The fracture stability prediction module is used to calculate the shear stress and effective normal stress on the fracture surface based on the Mohr-Coulomb theory, the quantitative characterization results of the fracture, and the prediction results of the geostress and geostress direction. Based on the shear stress and effective normal stress on the fracture surface, a fracture stability prediction planar diagram is obtained.

[0038] A third aspect of this application provides a processor configured to perform the above-described seismic assessment method for fault stability.

[0039] A fourth aspect of this application provides a machine-readable storage medium storing instructions that, when executed by a processor, configure the processor to perform the aforementioned seismic assessment method for fault stability.

[0040] Compared with the prior art, the above-mentioned technical solution of the present invention has the following beneficial effects:

[0041] This application provides a seismic assessment method and apparatus for fault stability. The method uses seismic fault and geostress field prediction results to calculate the shear stress and effective normal stress of the fault surface to assess the stability of the fault surface. It can quantitatively assess the stability of the fault to guide well location deployment and avoid drilling risks.

[0042] Other features and advantages of the embodiments of this application will be described in detail in the following detailed description section. Attached Figure Description

[0043] The accompanying drawings are provided to further illustrate embodiments of the present invention and form part of the specification. They are used together with the following detailed description to explain the embodiments of the present invention, but do not constitute a limitation thereof. In the drawings:

[0044] Figure 1 This illustration schematically shows the overall flow diagram of a seismic assessment method for fault stability according to an embodiment of this application;

[0045] Figure 2 This illustration schematically shows a detailed flowchart of a seismic assessment method for fault stability according to an embodiment of this application;

[0046] Figure 3 This schematic diagram illustrates the predicted planar distribution of overlying formation pressure according to an embodiment of this application.

[0047] Figure 4 This schematic diagram illustrates the direction of the maximum horizontal principal stress resulting from the superposition of horizontal principal stress differences according to an embodiment of this application.

[0048] Figure 5 A schematic diagram illustrating the fracture space channel and its quantitative characterization according to an embodiment of this application is shown.

[0049] Figure 6 A schematic diagram illustrating a fracture sliding risk prediction plan according to an embodiment of this application is shown.

[0050] Figure 7 A schematic diagram of a seismic assessment apparatus for fault stability according to an embodiment of this application is shown. Detailed Implementation

[0051] To make the objectives, technical solutions, and advantages of the embodiments of this application clearer, the technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. It should be understood that the specific embodiments described herein are only for illustration and explanation of the embodiments of this application and are not intended to limit the embodiments of this application. All other embodiments obtained by those skilled in the art based on the embodiments of this application without creative effort are within the scope of protection of this application.

[0052] Figure 1 The diagram illustrates the overall flow of a seismic assessment method for fault stability according to an embodiment of this application. Figure 2 The diagram illustrates a specific flowchart of a seismic assessment method for fault stability according to an embodiment of this application. Figure 1-2 As shown in one embodiment of this application, a seismic assessment method for fault stability is provided to quantitatively assess fault stability and solve the engineering prediction problem of avoiding high-slip-risk faults during drilling. The method includes the following steps:

[0053] Step 110: Obtain basic seismic data for the drilling section; wherein, the basic seismic data for the drilling section includes seismic data and actual drilling data.

[0054] Specifically, the first step is to acquire the basic data for seismic assessment of fracture mechanical stability. Seismic data includes pre-stack time-domain migration gathers and full-stack time-domain migration data. Actual drilling data includes well coordinates, well layers, well shows, well trajectories, well logging data from the surface to the target subsurface layer (including but not limited to P-wave, density, S-wave, natural gamma, total hydrocarbon curves, and gamma-while-drilling data), elemental logging curves, actual drilling stress data (maximum horizontal principal stress and direction, minimum horizontal principal stress, overlying formation pressure, pore pressure, etc.), FMI imaging logging data, actual drilling engineering formation reconstruction profiles, and microseismic monitoring data.

[0055] Step 120: Based on the actual drilling data, perform fracture interpretation and identify the location of fracture development in the drilling section.

[0056] Specifically, the locations of fracture development in the drilling section (including fracture development locations in the vertical and horizontal sections of the drilling) are identified through actual drilling formation restoration profiles, FMI imaging logging data, conventional logging data (natural gamma, shallow and deep resistivity, sonic transit time, density, and neutrons), horizontal section logging (total hydrocarbon curves, gamma while drilling), and microseismic monitoring results.

[0057] Step 130: Based on the earthquake data, extract earthquake attributes that can predict faults.

[0058] Specifically, based on pre-stack migration gathers in the time domain, the drilling trajectories in the depth domain are converted to the time domain by extracting seismic wavelets and creating synthetic seismic records, facilitating matching with the time-domain full-stack migration data. Furthermore, faults with more than half a phase discontinuity are manually interpreted from the time-domain seismic data. Various seismic attributes currently available for fault prediction are extracted, including tectonic attributes (similarity, curvature, texture, maximum likelihood volume, etc.), geometric attributes (volume curvature, dip angle, azimuth angle, etc.), instantaneous attributes (amplitude, frequency, phase, envelope, energy, ant-body anomalies, etc.), and AI-based fault prediction.

[0059] Step 140: The location of the fracture development in the drilling section and the seismic attributes are calibrated to determine the sensitive attribute volume, and the quantitative characterization result of the fracture is determined based on the sensitive attribute volume.

[0060] Figure 5 This diagram schematically illustrates the spatial channel and quantitative characterization of a fracture according to an embodiment of this application. Specifically, the location of fracture development in the drilling section is calibrated with seismic attributes, and 3-4 sensitive attribute bodies (typically including but not limited to volume curvature, ant-like structures, and AI-predicted fractures) are selected as potential fractures. Preferred fracture prediction attribute bodies (dip angle, azimuth angle, similarity, or AI-predicted fractures or curvature) are extracted along the main target layer. The extracted attribute values ​​(dip angle, similarity, or curvature) are intersected, and points with high dip angles, low similarity, or high volume curvature values ​​are filtered out. The set of these points in space constitutes the fracture channel. The location and characteristic values ​​(dip angle, dip direction) of these points are determined, and each fracture fragment within the fracture channel can be simulated based solely on these values. Figure 5 As shown.

[0061] Step 150: Based on the seismic data, perform elastic parameter inversion to obtain the elastic parameter volume, and determine the rock mechanics parameter volume based on the elastic parameter volume.

[0062] Specifically, elastic parameter inversion is performed using pre-stack migration gathers in the time domain to obtain elastic parameter volumes such as P-wave, S-wave, and density. Based on these elastic parameter volumes, rock mechanics parameters such as Young's modulus, Poisson's ratio, and Lamé constant are calculated.

[0063] Step 160: Determine the geostress prediction result based on the elastic parameter body and the rock mechanical parameter body.

[0064] Figure 3A schematic diagram illustrating the planar distribution of overburden pressure prediction according to an embodiment of this application is provided. Specifically, using the aforementioned elastic parameters and rock mechanics parameters, the normal compaction curve of the acoustic and density curves is calculated using the relationship between porosity and depth (based on the Athy equation for earthquake travel time); the mudstone indicator trend line is calculated using resistivity or gamma curves, and the clay content is calculated; for overpressured strata, a normal density curve is created using the normal compaction curve of density and the actual measured density curve; the overburden pressure is calculated using density curve integration; the formation pore pressure is calculated using the Eaton empirical formula; and the horizontal principal stress is calculated using the Huang model. Based on the above process, the overburden pressure volume, the formation pore pressure volume, and the horizontal stress volume can be obtained.

[0065] Step 170: Based on thin plate theory, geological, mechanical and mathematical models are established using rock mechanics parameters. The three-dimensional finite element differential simulation method is used to determine the predicted results of the geostress direction.

[0066] Figure 4 This diagram schematically illustrates the direction of the maximum horizontal principal stress resulting from the superposition of horizontal principal stress differences according to an embodiment of this application. Specifically, based primarily on thin plate theory, a geological, mechanical, and mathematical model is established using rock mechanics parameters. The direction of the maximum horizontal principal stress is simulated using a three-dimensional finite element differential simulation method. The results are then calibrated against the measured direction of the maximum principal stress. Based on the calibration results, the model parameters are continuously optimized and adjusted until the match with the actual drilled direction of the maximum principal stress exceeds 70%. Figure 4 As shown.

[0067] Step 180: Based on the Mohr-Coulomb theory and the quantitative characterization results of the fracture, combined with the prediction results of the geostress and the geostress direction, calculate the shear stress and effective normal stress of the fracture surface, and obtain the fracture stability prediction planar diagram based on the shear stress and effective normal stress of the fracture surface.

[0068] Figure 6 A schematic diagram illustrating the fracture slip risk prediction planar diagram according to an embodiment of this application is provided. Specifically, guided by the Mohr-Coulomb criterion (the classical theory of fracture surface slip in mechanics), and utilizing the results obtained from the above process—namely, the maximum horizontal principal stress and its direction, the minimum horizontal principal stress, and the cross-sectional dip angle—the shear stress planar distribution diagram and the effective normal stress planar distribution diagram of the fracture surface are calculated. By comparing the magnitudes of the shear stress and the frictional force (effective normal stress), a fracture stability prediction planar diagram is obtained, as shown below. Figure 6 As shown.

[0069] Figure 2 This is a flowchart illustrating a seismic assessment method for fault stability in one embodiment. It should be understood that, although... Figure 2The steps in the flowchart are shown sequentially as indicated by the arrows, but these steps are not necessarily executed in the order indicated by the arrows. Unless otherwise specified herein, there is no strict order in which these steps are executed, and they can be performed in other orders. Figure 2 At least some of the steps in the process may include multiple sub-steps or multiple stages. These sub-steps or stages are not necessarily completed at the same time, but can be executed at different times. The execution order of these sub-steps or stages is not necessarily sequential, but can be executed in turn or alternately with other steps or at least some of the sub-steps or stages of other steps.

[0070] The method described in this application borrows mature seismic inversion techniques, seismic attribute extraction techniques, the Eaton formation pore pressure empirical formula in rock mechanics, the three-dimensional finite element differential simulation method, in-situ stress calculation based on the Huang model, and the Mohr-Coulomb criterion, a classical theory of fracture surface slip dynamics, and proposes an original technique for cross-sectional seismic assessment. While the Mohr-Coulomb criterion is commonly used to assess wellbore fracture surface slip, it can only predict slip risk at the drilling location regionally. This application leverages the advantage of the continuous spatial distribution of seismic data, enabling slip risk prediction for regional fracture surfaces, slip risk assessment at different locations on the fracture surface, and risk assessment at different stress points. Compared to later methods using digital stochastic modeling for fracture risk assessment, the data between wellbores comes from deterministic seismic data, rather than mathematical interpolation methods using stochastic spatial modeling. This results in less computational load and higher prediction accuracy and stability.

[0071] The method described in this application has been effectively utilized in the exploration and development of deep shale gas in the southern Sichuan Basin. The method has yielded good results in fracture stability assessment compared to actual drilling, and has currently supported the optimized pilot test scheme for deep shale gas in the Luzhou area. The number of wells deployed in the Luzhou 203 well area has increased by 16%, and drilling plans for more than 20 ongoing wells have been adjusted. This has improved the utilization rate of underground resources, effectively guided production, significantly reduced the probability of well casing deformation, saved drilling time, and improved economic efficiency.

[0072] In one embodiment, such as Figure 7 As shown, a seismic assessment device for fault stability is provided, the device comprising:

[0073] The basic data acquisition module 210 is used to acquire basic seismic data of the drilling section; wherein, the basic seismic data of the drilling section includes seismic data and actual drilling data;

[0074] The fracture interpretation module 220 is used to interpret fractures based on the actual drilling data and identify the location of fracture development in the drilling section.

[0075] The earthquake attribute extraction module 230 is used to extract earthquake attributes that can predict faults based on the earthquake data.

[0076] The calibration module 240 is used to calibrate the location of the fracture development in the drilling section and the seismic attributes, determine the sensitive attribute volume, and determine the quantitative characterization result of the fracture based on the sensitive attribute volume.

[0077] The inversion module 250 is used to perform elastic parameter inversion based on the seismic data, obtain the elastic parameter volume, and determine the rock mechanics parameter volume based on the elastic parameter volume.

[0078] The in-situ stress prediction module 260 is used to determine the in-situ stress prediction result based on the elastic parameter body and the rock mechanics parameter body;

[0079] The geostress direction prediction module 270 is used to establish geological, mechanical and mathematical models based on thin plate theory and rock mechanics parameters, and to determine the geostress direction prediction results using the three-dimensional finite element difference simulation method.

[0080] The fracture stability prediction module 280 is used to calculate the shear stress and effective normal stress on the fracture surface based on the Mohr-Coulomb theory, the quantitative characterization results of the fracture, and the prediction results of the geostress and geostress direction. Based on the shear stress and effective normal stress on the fracture surface, a fracture stability prediction planar diagram is obtained.

[0081] The earthquake assessment device for fault stability includes a processor and a memory. The aforementioned basic data acquisition module, fault interpretation module, earthquake attribute extraction module, calibration module, inversion module, geostress prediction module, geostress direction prediction module, and fault stability prediction module are all stored as program units in the memory. The processor executes the aforementioned program units stored in the memory to achieve the corresponding functions.

[0082] The processor contains a kernel, which retrieves the corresponding program units from memory. One or more kernels can be configured, and adjusting kernel parameters allows for the implementation of seismic assessment methods for fault stability.

[0083] The memory may include non-permanent memory in computer-readable media, such as random access memory (RAM) and / or non-volatile memory, such as read-only memory (ROM) or flash RAM, and the memory includes at least one memory chip.

[0084] This invention provides a storage medium storing a program that, when executed by a processor, implements a seismic assessment method for fault stability.

[0085] This invention provides a processor for running a program, wherein the program executes a seismic assessment method for fault stability.

[0086] This invention provides a device including a processor, a memory, and a program stored in the memory and executable on the processor. When the processor executes the program, it performs the following steps:

[0087] Step 110: Obtain basic seismic data for the drilling section; wherein, the basic seismic data for the drilling section includes seismic data and actual drilling data.

[0088] Step 120: Based on the actual drilling data, perform fracture interpretation and identify the location of fracture development in the drilling section.

[0089] Step 130: Based on the earthquake data, extract earthquake attributes that can predict faults.

[0090] Step 140: The location of the fracture development in the drilling section and the seismic attributes are calibrated to determine the sensitive attribute volume, and the quantitative characterization result of the fracture is determined based on the sensitive attribute volume.

[0091] Step 150: Based on the seismic data, perform elastic parameter inversion to obtain the elastic parameter volume, and determine the rock mechanics parameter volume based on the elastic parameter volume.

[0092] Step 160: Determine the geostress prediction result based on the elastic parameter body and the rock mechanical parameter body.

[0093] Step 170: Based on thin plate theory, geological, mechanical and mathematical models are established using rock mechanics parameters. The three-dimensional finite element differential simulation method is used to determine the predicted results of the geostress direction.

[0094] Step 180: Based on the Mohr-Coulomb theory and the quantitative characterization results of the fracture, combined with the prediction results of the geostress and the geostress direction, calculate the shear stress and effective normal stress of the fracture surface, and obtain the fracture stability prediction planar diagram based on the shear stress and effective normal stress of the fracture surface.

[0095] Optionally, fracture interpretation is performed based on the actual drilling data to identify the location of fracture development in the drilling section, including: interpreting the location of fracture development in the drilling section using actual drilling engineering recovery maps, FMI imaging logging data, conventional logging data, horizontal section logging data, and microseismic monitoring data.

[0096] Optionally, the seismic data includes pre-stack time-domain migration gathers; the step of performing elastic parameter inversion based on the seismic data to obtain an elastic parameter volume includes: performing elastic parameter inversion using pre-stack time-domain migration gathers to obtain an elastic parameter volume.

[0097] Optionally, the geostress prediction results include overlying formation pressure; the method includes:

[0098] Based on the elastic parameter body and the rock mechanics parameter body, the normal compaction curve of density is calculated using the seismic travel time equation;

[0099] A density curve is created using the normal compaction curve of density and the actual measured density curve.

[0100] The pressure of the overlying strata is calculated by integrating the density curve.

[0101] Optionally, the geostress prediction results also include formation pore pressure; the method includes:

[0102] Based on the elastic parameter body and the rock mechanics parameter body, formation pore pressure is calculated using Eaton's empirical formula.

[0103] Optionally, the geostress prediction results may also include horizontal principal stresses; the method includes: calculating the horizontal principal stresses using the Huang model based on the elastic parameter body and the rock mechanics parameter body.

[0104] Optionally, a fracture stability prediction planar diagram is obtained based on the fracture surface shear stress and effective normal stress, including: comparing the magnitudes of the fracture surface shear stress and the effective normal stress to obtain a comparison result; and drawing the fracture stability prediction planar diagram based on the comparison result.

[0105] The method described in this application can guide drilling to avoid areas with high risk of fracture and slippage, improve the guiding role of seismic results in shale gas exploration and development, support the overall platform deployment and optimization, and improve the utilization rate of underground resources.

[0106] Those skilled in the art will understand that embodiments of this application can be provided as methods, systems, or computer program products. Therefore, this application can take the form of a completely hardware embodiment, a completely software embodiment, or an embodiment combining software and hardware aspects. Furthermore, this application can take the form of a computer program product embodied on one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) containing computer-usable program code.

[0107] This application is described with reference to flowchart illustrations and / or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of this application. It will be understood that each block of the flowchart illustrations and / or block diagrams, and combinations of blocks in the flowchart illustrations and / or block diagrams, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, special-purpose computer, embedded processor, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, generate instructions for implementing the flowchart... Figure 1 One or more processes and / or boxes Figure 1 A device that provides the functions specified in one or more boxes.

[0108] These computer program instructions may also be stored in a computer-readable storage medium that can direct a computer or other programmable data processing device to function in a particular manner, such that the instructions stored in the computer-readable storage medium produce an article of manufacture including instruction means, which are implemented in a process Figure 1 One or more processes and / or boxes Figure 1 The function specified in one or more boxes.

[0109] These computer program instructions may also be loaded onto a computer or other programmable data processing equipment to cause a series of operational steps to be performed on the computer or other programmable equipment to produce a computer-implemented process, thereby providing instructions that execute on the computer or other programmable equipment for implementing the process. Figure 1 One or more processes and / or boxes Figure 1 The steps of the function specified in one or more boxes.

[0110] In a typical configuration, a computing device includes one or more processors (CPU), input / output interfaces, network interfaces, and memory.

[0111] Memory may include non-persistent memory in computer-readable media, such as random access memory (RAM) and / or non-volatile memory, such as read-only memory (ROM) or flash RAM. Memory is an example of computer-readable media.

[0112] Computer-readable media includes both permanent and non-permanent, removable and non-removable media that can store information using any method or technology. Information can be computer-readable instructions, data structures, modules of programs, or other data. Examples of computer storage media include, but are not limited to, phase-change memory (PRAM), static random access memory (SRAM), dynamic random access memory (DRAM), other types of random access memory (RAM), read-only memory (ROM), electrically erasable programmable read-only memory (EEPROM), flash memory or other memory technologies, CD-ROM, digital versatile optical disc (DVD) or other optical storage, magnetic tape, magnetic magnetic disk storage or other magnetic storage devices, or any other non-transferable medium that can be used to store information accessible by a computing device. As defined herein, computer-readable media does not include transient computer-readable media, such as modulated data signals and carrier waves.

[0113] It should also be noted that the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such process, method, article, or apparatus. Unless otherwise specified, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes that element.

[0114] The above are merely embodiments of this application and are not intended to limit the scope of this application. Various modifications and variations can be made to this application by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this application should be included within the scope of the claims of this application.

Claims

1. A seismic assessment method for fault stability, characterized in that, The method includes: Obtain basic seismic data for the drilling section; wherein, the basic seismic data for the drilling section includes seismic data and actual drilling data; Based on the actual drilling data, fracture interpretation was performed to identify the location of fracture development in the drilling section. Based on the earthquake data, earthquake attributes that can predict faults are extracted; The location of the fracture development in the drilling section and the seismic attributes are calibrated to determine the sensitive attribute volume, and the quantitative characterization results of the fracture are determined based on the sensitive attribute volume. Based on the seismic data, elastic parameters are inverted to obtain the elastic parameter volume, and the rock mechanics parameter volume is determined based on the elastic parameter volume. Based on the elastic parameter body and the rock mechanics parameter body, the geostress prediction results are determined; Based on thin plate theory, using rock mechanics parameters, a geological, mechanical and mathematical model is established, and the three-dimensional finite element difference simulation method is used to determine the predicted results of the geostress direction. Based on the Mohr-Coulomb theory, and combined with the results of quantitative characterization of the fracture, the shear stress and effective normal stress of the fracture surface are calculated, and a fracture stability prediction planar diagram is obtained based on the shear stress and effective normal stress of the fracture surface. The geostress prediction results include overlying formation pressure; the method includes: Based on the elastic parameter body and the rock mechanics parameter body, the normal compaction curve of density is calculated using the seismic travel time equation; A first density curve is created using the normal compaction curve of density and the actual measured density curve; The pressure of the overlying strata was calculated by integrating the first density curve.

2. The seismic assessment method for fault stability according to claim 1, characterized in that, Based on the actual drilling data, fracture interpretation is performed to identify the location of fracture development in the drilling section, including: The location of fracture development in the drilling section was interpreted using actual drilling engineering recovery maps, FMI imaging logging data, conventional logging data, and microseismic monitoring data.

3. The seismic assessment method for fault stability according to claim 1, characterized in that, The seismic data includes pre-stack time-domain migration gathers; the elastic parameter inversion based on the seismic data to obtain the elastic parameter volume includes: Elastic parameters are inverted using pre-stack migration gathers in the time domain to obtain the elastic parameter volume.

4. The seismic assessment method for fault stability according to claim 1, characterized in that, The geostress prediction results also include formation pore pressure; the method includes: Based on the elastic parameter body and the rock mechanics parameter body, formation pore pressure is calculated using Eaton's empirical formula.

5. The seismic assessment method for fault stability according to claim 4, characterized in that, The geostress prediction results also include horizontal principal stresses; the method includes: Based on the elastic parameter body and the rock mechanics parameter body, the horizontal principal stress is calculated using the Huang model.

6. The seismic assessment method for fault stability according to claim 1, characterized in that, A fracture stability prediction planar diagram is obtained based on the shear stress and effective normal stress on the fracture surface, including: Compare the magnitudes of the shear stress and the effective normal stress on the fracture surface to obtain the comparison results; A fracture stability prediction planar diagram is drawn based on the comparison results.

7. A seismic assessment device for fault stability, characterized in that, The device includes: The basic data acquisition module is used to acquire basic seismic data for the drilling section; wherein, the basic seismic data for the drilling section includes seismic data and actual drilling data; The fracture interpretation module is used to interpret fractures based on the actual drilling data and identify the location of fracture development in the drilling section. The earthquake attribute extraction module is used to extract earthquake attributes that can predict faults based on the earthquake data. The calibration module is used to calibrate the location of the fracture development in the drilling section and the seismic attributes, determine the sensitive attribute volume, and determine the quantitative characterization result of the fracture based on the sensitive attribute volume. The inversion module is used to perform elastic parameter inversion based on the seismic data, obtain the elastic parameter volume, and determine the rock mechanics parameter volume based on the elastic parameter volume. The geostress prediction module is used to determine the geostress prediction result based on the elastic parameter body and the rock mechanics parameter body; The geostress direction prediction module is used to establish geological, mechanical and mathematical models based on thin plate theory and rock mechanics parameters, and to determine the geostress direction prediction results using three-dimensional finite element difference simulation method. The fracture stability prediction module is used to calculate the shear stress and effective normal stress on the fracture surface based on the Mohr-Coulomb theory, the quantitative characterization results of the fracture, and the prediction results of the geostress and geostress direction. Based on the shear stress and effective normal stress on the fracture surface, a fracture stability prediction planar diagram is obtained. The geostress prediction module is specifically used for: Based on the elastic parameter body and the rock mechanics parameter body, the normal compaction curve of density is calculated using the seismic travel time equation; A first density curve is created using the normal compaction curve of density and the actual measured density curve; The pressure of the overlying strata was calculated by integrating the first density curve.

8. A processor, characterized in that, The seismic assessment method for fault stability is configured to perform any one of claims 1 to 6.

9. A machine-readable storage medium storing instructions thereon, characterized in that, When executed by a processor, this instruction causes the processor to be configured to perform the seismic assessment method for fault stability as described in any one of claims 1 to 6.

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