Pre-drilling evaluation method and device for vertical well wall stability based on seismic data

Through the pre-drilling evaluation method based on seismic data, the formation elastic parameters, ground stress and rock strength parameters are used for numerical simulation, which solves the problem of insufficient evaluation of well wall stability during drilling in Pengzhou gas field in Sichuan Basin, effectively judges the types of damage that may occur during drilling, and reduces the drilling risk.

CN120100418APending Publication Date: 2025-06-06CHINA PETROLEUM & CHEMICAL CORP +1
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Patent Information

Application Number
CN202311655873.1
Authority / Receiving Office
CN · China
Patent Type
Applications(China)
Current Assignee / Owner
Filing Date
2023-12-05
Publication Date
2025-06-06

AI Technical Summary

Technical Problem

During the drilling process of Pengzhou gas field in Sichuan Basin, due to the complex geological conditions and insufficient common well wall stability evaluation methods, resulting in frequent well surges, well leakage, block drops, and drilling intermittent during drilling, which increases the drilling cycle and cost and affects the efficient exploration and development of gas fields.

Method used

A pre-drilling evaluation method based on seismic data is proposed. By obtaining the relevant data before drilling of the target well, conducting pre-stack seismic inversion before and after stacking, obtaining formation elastic parameters, calculating formation pressure and ground stress parameters, obtaining rock strength parameters, and using these parameters to perform numerical simulation of the stability of the periwell wall, analyzing the magnitude relationship between vertical stress, tangential stress and radial stress to judge the possible tensile failure and shear failure during drilling.

Benefits of technology

Pre-drilling evaluation of the stability of the vertical well wall was achieved. Through the utilization of seismic data, the mechanical parameters of the formation and rock were extracted, the stress state around the well was simulated, and the types of damage that may occur during the drilling process were effectively judged, thereby reducing the drilling risk.

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Abstract

The invention discloses a seismic data-based pre-drilling evaluation method and device for vertical well wall stability. The method comprises the following steps of: obtaining related data of pre-drilling well drilling design of a target well; pre-stack and post-stack seismic inversion is carried out, and stratum elastic parameters of the target well position are obtained; calculating formation pressure and ground stress parameters of the target well position based on the formation elastic parameters; obtaining the strength parameter, cohesion and internal friction angle of the stratum rock at the target well position through a rock physical test experiment or based on the stratum elastic parameters; carrying out numerical simulation on the stability of the well wall around the well to obtain vertical stress, tangential stress and radial stress in different directions around the well; and analyzing the magnitude relationship of the vertical stress, the tangential stress and the radial stress along different directions of the well circumference so as to judge the tensional failure and the shear failure possibly occurring around the well circumference in the drilling process, and completing the pre-drilling evaluation of the well wall stability of the drilling well. According to the method, the pre-drilling evaluation of the vertical well wall stability can be realized.
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Description

Technical Field

[0001] The present invention belongs to the field of petroleum exploration, and more specifically, relates to a method and a device for pre-drilling evaluation of vertical wellbore stability based on seismic data. Background Art

[0002] Pengzhou Gas Field in Sichuan Basin is located in the Longmenshan foreland tectonic belt. Due to the complex geological conditions, the early drilling process was prone to well kick, well leakage, block drop, and drill bit sticking, which increased the drilling cycle and cost, and affected the efficient exploration and development of the gas field. In order to reduce the drilling risk, it is necessary to carry out pre-drilling wellbore stability evaluation. At present, most of the commonly used wellbore stability evaluation methods are in the fields of drilling and geology, and there is little research on pre-drilling wellbore stability evaluation based on seismic data. Summary of the invention

[0003] The purpose of the present invention is to provide a method and device for pre-drilling evaluation of vertical wellbore stability based on seismic data, so as to realize pre-drilling evaluation of vertical wellbore stability.

[0004] To achieve the above objectives, in a first aspect, the present invention proposes a method for pre-drilling evaluation of vertical wellbore stability based on seismic data, comprising:

[0005] Acquire relevant data of drilling design before drilling the target well, wherein the relevant data includes mud density;

[0006] Based on the pre-stack and post-stack seismic data of the target well area, pre-stack and post-stack seismic inversion is carried out to obtain the formation elastic parameters at the target well location;

[0007] Calculate the formation pressure and ground stress parameters at the target well location based on the obtained formation elastic parameters;

[0008] Obtaining strength parameters, cohesion and internal friction angle of formation rock at the target well location through rock physics test experiments or based on the formation elastic parameters;

[0009] Using the mud density and the formation pressure and ground stress parameters, numerical simulation of wellbore stability around the well is carried out to obtain the magnitude of vertical stress, tangential stress and radial stress at different directions around the well;

[0010] Analyze the magnitude relationship of vertical stress, tangential stress and radial stress at different directions around the well to determine the tensile and shear failures that may occur around the well during drilling and complete the pre-drilling evaluation of the wellbore stability.

[0011] Optionally, pre-stack and post-stack seismic inversion is performed based on the pre-stack and post-stack seismic data of the target well work area to obtain the formation elastic parameters at the target well location, including:

[0012] Collect pre-stack and post-stack seismic data of the target well area, conduct pre-stack and post-stack seismic inversion, and obtain three-dimensional data of P-wave velocity, S-wave velocity, and density;

[0013] The formation elastic parameters are calculated based on the obtained three-dimensional data of P-wave velocity, S-wave velocity and density and on the basis of rock physics relationships.

[0014] Optionally, the formation elastic parameters include Young's modulus and Poisson's ratio.

[0015] Optionally, the calculating the formation pressure and ground stress parameters at the target well location based on the obtained formation elastic parameters includes:

[0016] Based on the longitudinal wave velocity, the Young's modulus, the Poisson's ratio and the anisotropy parameters, the formation pressure prediction model and the ground stress prediction model are used to carry out formation pressure and ground stress prediction based on seismic data to obtain the magnitude and direction of the ground stress and the formation pressure from shallow to deep formations of the target well.

[0017] Optionally, the geostress includes vertical principal stress, maximum horizontal principal stress and lowest horizontal principal stress.

[0018] Optionally, the step of obtaining the strength parameters, cohesion and internal friction angle of the formation rock at the target well location through a rock physics test experiment or based on the formation elastic parameters includes:

[0019] Based on rock physics experimental analysis or rock physics experimental empirical parameters, the strength parameters, cohesion and internal friction angle of the formation rock are given;

[0020] Alternatively, based on the formation elastic parameters, the strength parameters, cohesion and internal friction angle of the formation rock are calculated through rock physical relationships.

[0021] In a second aspect, the present invention provides an electronic device, the electronic device comprising:

[0022] at least one processor; and,

[0023] a memory communicatively connected to the at least one processor; wherein,

[0024] The memory stores instructions that can be executed by the at least one processor, and the instructions are executed by the at least one processor so that the at least one processor can execute any pre-drilling evaluation method for vertical wellbore stability based on seismic data as described in the first aspect.

[0025] In a third aspect, the present invention proposes a non-transitory computer-readable storage medium, which stores computer instructions, and the computer instructions are used to enable a computer to execute any of the pre-drilling evaluation methods for vertical wellbore stability based on seismic data as described in the first aspect.

[0026] In a fourth aspect, the present invention provides a pre-drilling evaluation device for vertical wellbore stability based on seismic data, comprising:

[0027] A drilling data acquisition module is used to acquire relevant data of the drilling design before drilling the target well, wherein the relevant data includes mud density;

[0028] The elastic parameter calculation module is used to carry out pre-stack and post-stack seismic inversion based on the pre-stack and post-stack seismic data of the target well work area to obtain the formation elastic parameters at the target well location;

[0029] A geostress calculation module, used to calculate the formation pressure and geostress parameters at the target well location based on the obtained formation elastic parameters;

[0030] A rock strength parameter calculation module, used to obtain the strength parameters, cohesion and internal friction angle of the formation rock at the target well location through rock physics test experiments or based on the formation elastic parameters;

[0031] A simulation calculation module is used to carry out numerical simulation of wellbore stability around the well using the mud specific gravity and the formation pressure and ground stress parameters, and obtain the magnitude of vertical stress, tangential stress and radial stress at different directions around the well;

[0032] The evaluation module is used to analyze the magnitude relationship of vertical stress, tangential stress and radial stress at different locations around the well to determine the tensile and shear failures that may occur around the well during drilling and complete the pre-drilling evaluation of the wellbore stability.

[0033] Optionally, pre-stack and post-stack seismic inversion is performed based on the pre-stack and post-stack seismic data of the target well work area to obtain the formation elastic parameters at the target well location, including:

[0034] Collect pre-stack and post-stack seismic data of the target well area, conduct pre-stack and post-stack seismic inversion, and obtain three-dimensional data of P-wave velocity, S-wave velocity, and density;

[0035] The formation elastic parameters are calculated based on the obtained three-dimensional data of P-wave velocity, S-wave velocity and density and on the basis of rock physics relationships.

[0036] The beneficial effects of the present invention are:

[0037] The present invention makes full use of the spatial three-dimensional information of earthquakes, extracts the elastic parameters of the formation from the pre-stack seismic data, and further obtains mechanical parameters such as rock strength, ground stress and formation pressure based on rock physical relationships, and then carries out stress disturbance analysis around the well based on the drilling design parameters of the well to be drilled, simulates the variation law of effective annular stress with azimuth and radius, and finally judges the tensile damage and shear damage that may occur around the well during the drilling process based on the size relationship between the vertical stress, tangential stress and radial stress around the well, thereby realizing the pre-drilling evaluation of the wellbore stability of vertical well drilling.

[0038] The system of the present invention has other characteristics and advantages, which will be apparent from the drawings incorporated herein and the following detailed description, or will be described in detail in the drawings incorporated herein and the following detailed description, which together serve to explain the specific principles of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0039] The above and other objects, features and advantages of the present invention will become more apparent through a more detailed description of exemplary embodiments of the present invention in conjunction with the accompanying drawings, in which like reference numerals generally represent like components.

[0040] Figure 1 A flow chart showing the steps of a method for pre-drilling evaluation of vertical wellbore stability based on seismic data according to the present invention is shown. DETAILED DESCRIPTION

[0041] Wellbore stability refers to the tensile damage (well leakage) and shear damage (well collapse) of the wellbore during the drilling process. The present invention aims at the wellbore stability problem that may occur during the drilling of a vertical well, and proposes a pre-drilling evaluation method and device for the wellbore stability of a vertical well based on seismic data. The method is based on seismic data, and obtains parameters such as formation three-dimensional stress parameters and formation pressure through the method of seismic inversion. Further, based on geological elements (ground stress, pore pressure) and engineering elements (drilling fluid density, drilling fluid temperature, wellbore trajectory), the stress disturbance analysis around the wellbore is carried out to simulate the change law of effective annular stress with azimuth and radius. According to the relationship between the vertical stress, tangential stress and radial stress around the wellbore, the tensile damage and shear damage that may occur around the wellbore during the drilling process are judged, thereby realizing the pre-drilling evaluation of the wellbore stability based on seismic data.

[0042] The present invention will be described in more detail below with reference to the accompanying drawings. Although preferred embodiments of the present invention are shown in the accompanying drawings, it should be understood that the present invention can be implemented in various forms and should not be limited by the embodiments set forth herein. On the contrary, these embodiments are provided to make the present invention more thorough and complete, and to fully convey the scope of the present invention to those skilled in the art.

[0043] Example 1

[0044] like Figure 1 As shown, this embodiment provides a method for pre-drilling evaluation of vertical wellbore stability based on seismic data, comprising:

[0045] S1: Obtain relevant data of drilling design before drilling the target well, including mud density;

[0046] S2: Based on the pre-stack and post-stack seismic data of the target well area, pre-stack and post-stack seismic inversion is carried out to obtain the formation elastic parameters at the target well location;

[0047] This step specifically includes:

[0048] Collect pre-stack and post-stack seismic data of the target well area, conduct pre-stack and post-stack seismic inversion, and obtain three-dimensional data of P-wave velocity, S-wave velocity, and density;

[0049] According to the obtained three-dimensional data of P-wave velocity, S-wave velocity and density, the formation elastic parameters are calculated based on rock physics relations.

[0050] Among them, the formation elastic parameters include Young's modulus and Poisson's ratio.

[0051] S3: Calculating formation pressure and ground stress parameters at the target well location based on the obtained formation elastic parameters;

[0052] This step specifically includes:

[0053] Based on the P-wave velocity, Young's modulus, Poisson's ratio and anisotropy parameters, the formation pressure prediction model and the ground stress prediction model are used to predict the formation pressure and ground stress based on seismic data, and the magnitude and direction of the ground stress and the formation pressure from shallow to deep formations of the target well are obtained. Among them, the ground stress includes the vertical principal stress, the maximum horizontal principal stress and the lowest horizontal principal stress.

[0054] S4: Obtain the strength parameters, cohesion and internal friction angle of the formation rock at the target well location through rock physics test experiments or based on formation elastic parameters;

[0055] This step specifically includes:

[0056] Based on rock physics experimental analysis or rock physics experimental empirical parameters, the strength parameters, cohesion and internal friction angle of the formation rock are given;

[0057] Alternatively, based on the formation elastic parameters, the strength parameters, cohesion and internal friction angle of the formation rock are calculated through rock physics relations.

[0058] S5: Using mud density, formation pressure and ground stress parameters, numerical simulation of wellbore stability is carried out to obtain the magnitude of vertical stress, tangential stress and radial stress at different locations around the well.

[0059] S6: Analyze the magnitude relationship of vertical stress, tangential stress and radial stress at different directions around the well to determine the tensile failure and shear failure that may occur around the well during drilling, and complete the pre-drilling evaluation of the wellbore stability.

[0060] Example 2

[0061] This embodiment provides a method for pre-drilling evaluation of vertical wellbore stability based on seismic data. The basic principle of the method is:

[0062] Underground rock formations are usually subjected to the combined effects of multiple forces such as vertical stress, horizontal stress and formation pressure. When the stress concentration on the wellbore breaks the equilibrium state of its original ground stress, the formation stress will be reconstructed and distributed. In this process, the damage to the wellbore wall caused by the reorganization of the formation stress may become wellbore instability.

[0063] If the mud density in the wellbore is too low, the stress on the wellbore wall will exceed the shear strength of the rock and cause shear failure, which is manifested as wellbore collapse and expansion or yielding and shrinkage; if the mud density is too high, tensile stress will be generated on the wellbore wall. When the tensile stress is greater than the tensile strength of the rock, tensile failure will occur, which is manifested as well leakage. Therefore, in engineering practice, the stress state near the wellbore can be changed by adjusting the mud density, thereby achieving the purpose of stabilizing the wellbore.

[0064] Therefore, the main factors affecting the stability of the wellbore during drilling include the magnitude and direction of ground stress, formation pressure, rock strength, drilling fluid density, drilling fluid temperature, drilling orientation and well inclination and other parameters.

[0065] Therefore, the basic idea of ​​conducting pre-drilling evaluation of wellbore stability is to calculate the magnitude and relationship of vertical stress, tangential stress and radial stress at the wellbore based on the drilling fluid density, drilling fluid temperature, drilling azimuth and well inclination parameters designed before drilling, combined with the magnitude and direction of the ground stress from shallow to deep strata at the well obtained based on seismic attributes and inversion, using the constructed wellbore stress disturbance equation, and analyze the tensile and shear failures that may occur in the wellbore based on certain judgment criteria, thereby realizing pre-drilling evaluation of wellbore stability based on seismic data.

[0066] The specific steps of a pre-drilling evaluation method for vertical wellbore stability based on seismic data in this embodiment are as follows:

[0067] Step 1: Collect relevant data on drilling design before drilling the target well, mainly mud density P m .

[0068] Step 2: Collect pre-stack and post-stack seismic data of the target well area, conduct pre-stack and post-stack seismic inversion, obtain the three-dimensional data volume ρ of P-wave vp, S-wave velocity vs, and density, and further calculate parameters such as Young's modulus E and Poisson's ratio υ based on rock physics relationships.

[0069] Step 3: Based on the obtained elastic parameters and anisotropy parameters such as P-wave velocity, Young's modulus and Poisson's ratio, and based on the formation pressure prediction model and the ground stress prediction model, the formation pressure and ground stress prediction based on seismic data are carried out to obtain the magnitude and direction of the ground stress from shallow to deep formations in the target well, the formation pressure P P The geostress includes the vertical principal stress σ v , maximum horizontal principal stress σ H and the horizontal lower principal stress σ h .

[0070] Step 4: If conditions permit for rock physics testing, rock strength parameters, cohesion and internal friction angle can be given based on rock physics experimental analysis or rock physics experimental empirical parameters. If they cannot be obtained through experiments, the strength parameters, cohesion and internal friction angle of the formation rock can be calculated based on the elastic parameters obtained from prestack seismic inversion and rock physics relationships.

[0071] Step 5: Conduct numerical simulation of wellbore stability around the well to obtain vertical stress σ at different positions θ around the well z , tangential stress σ θ and radial stress σ r size.

[0072] In this step, the calculation formula for numerical simulation using the mud density and the formation pressure and ground stress parameters is:

[0073] σ r =P m -αP p

[0074] σ θ =σ H +σ h -2(σ H -σ h )cos2θ-P p -P m

[0075] σ z =σ v -2υ(σ H -σ h )cos2θ-P p

[0076] Step 6: Analyze the vertical stress σ at different positions θ around the well z , tangential stress σ θ and radial stress σ r The size relationship can be used to determine the tensile and shear failures that may occur around the well during drilling, thereby realizing the pre-drilling evaluation of the wellbore stability based on seismic data.

[0077] Specifically, as the tangential stress σ θ increases, the compression effect of the wellbore wall increases. Once the wellbore wall tangential stress σ θ When the shear stress σ of the wellbore wall is greater than the rock strength, the wellbore wall will be compressed and damaged, causing the wellbore wall to collapse or collapse. θ When the shear force of rock failure needs to overcome the friction resistance generated when sliding along the failure action surface and the inherent cohesion of the rock, when the shear force of rock failure intersects with the stress moor circle, it means that the well wall is unstable and prone to collapse or collapse.

[0078] Example 3

[0079] This embodiment provides a method for pre-drilling evaluation of vertical wellbore stability based on seismic data, and the specific process is as follows:

[0080] Step 1: Collect relevant data on drilling design before drilling the target well, mainly mud density P m .

[0081] Step 2: Collect pre-stack and post-stack seismic data of the target well area, conduct pre-stack and post-stack seismic inversion, obtain the three-dimensional data volume ρ of P-wave vp, S-wave velocity vs, and density, and further calculate elastic parameters such as Young's modulus E and Poisson's ratio υ based on rock physics relationships.

[0082] Step 3: Based on the obtained elastic parameters and anisotropy parameters such as P-wave velocity, Young's modulus and Poisson's ratio, and based on the formation pressure prediction model and the ground stress prediction model, the formation pressure and ground stress prediction based on seismic data are carried out to obtain the magnitude and direction of the ground stress from shallow to deep formations in the target well, the formation pressure P P The geostress includes the vertical principal stress σ v , maximum horizontal principal stress σ H and the horizontal lower principal stress σ h .

[0083] Step 4: If conditions permit for rock physics testing, rock strength parameters, cohesion and internal friction angle can be given based on rock physics experimental analysis or rock physics experimental empirical parameters. If they cannot be obtained through experiments, the strength parameters, cohesion and internal friction angle of the formation rock can be calculated based on the elastic parameters obtained from prestack seismic inversion and rock physics relationships.

[0084] Step 5: Conduct numerical simulation of wellbore stability around the well to obtain vertical stress σ at different positions θ around the well z , tangential stress σ θ and radial stress σ r size.

[0085] Step 6: Analyze the vertical stress σ at different positions θ around the well z , tangential stress σ θ and radial stress σ r The size relationship can be used to determine the tensile and shear failures that may occur around the well during drilling, thereby realizing the pre-drilling evaluation of the wellbore stability based on seismic data.

[0086] As the tangential stress σ θ increases, the compression effect of the wellbore wall increases. Once the wellbore wall tangential stress σ θ When the shear stress σ of the wellbore wall is greater than the rock strength, the wellbore wall will be compressed and damaged, causing the wellbore wall to collapse or collapse. θ When the shear force of rock failure needs to overcome the friction resistance generated when sliding along the failure action surface and the inherent cohesion of the rock, when the shear force of rock failure intersects with the stress moor circle, it means that the well wall is unstable and prone to collapse or collapse.

[0087] Example 4

[0088] This embodiment provides a pre-drilling evaluation device for vertical wellbore stability based on seismic data, comprising:

[0089] A drilling data acquisition module is used to acquire relevant data of the drilling design before drilling the target well, wherein the relevant data includes mud density;

[0090] The elastic parameter calculation module is used to carry out pre-stack and post-stack seismic inversion based on the pre-stack and post-stack seismic data of the target well work area to obtain the formation elastic parameters at the target well location;

[0091] A geostress calculation module, used to calculate the formation pressure and geostress parameters at the target well location based on the obtained formation elastic parameters;

[0092] A rock strength parameter calculation module, used to obtain the strength parameters, cohesion and internal friction angle of the formation rock at the target well location through rock physics test experiments or based on the formation elastic parameters;

[0093] A simulation calculation module is used to carry out numerical simulation of wellbore stability around the well using the mud specific gravity and the formation pressure and ground stress parameters, and obtain the magnitude of vertical stress, tangential stress and radial stress at different directions around the well;

[0094] The evaluation module is used to analyze the magnitude relationship of vertical stress, tangential stress and radial stress at different locations around the well to determine the tensile and shear failures that may occur around the well during drilling and complete the pre-drilling evaluation of the wellbore stability.

[0095] In this embodiment, pre-stack and post-stack seismic inversion is performed based on the pre-stack and post-stack seismic data of the target well work area to obtain the formation elastic parameters at the target well location, including:

[0096] Collect pre-stack and post-stack seismic data of the target well area, conduct pre-stack and post-stack seismic inversion, and obtain three-dimensional data of P-wave velocity, S-wave velocity, and density;

[0097] The formation elastic parameters are calculated based on the obtained three-dimensional data of P-wave velocity, S-wave velocity and density and on the basis of rock physics relationships.

[0098] Example 5

[0099] This embodiment provides an electronic device, the electronic device comprising:

[0100] at least one processor; and,

[0101] a memory communicatively connected to the at least one processor; wherein,

[0102] The memory stores instructions that can be executed by the at least one processor, and the instructions are executed by the at least one processor so that the at least one processor can execute the pre-drilling evaluation method for vertical wellbore stability based on seismic data as described in any one of Examples 1-3.

[0103] The electronic device according to an embodiment of the present disclosure includes a memory and a processor, and the memory is used to store non-temporary computer-readable instructions. Specifically, the memory may include one or more computer program products, and the computer program product may include various forms of computer-readable storage media, such as volatile memory and / or non-volatile memory. The volatile memory may, for example, include a random access memory (RAM) and / or a cache memory (cache), etc. The non-volatile memory may, for example, include a read-only memory (ROM), a hard disk, a flash memory, etc.

[0104] The processor may be a central processing unit (CPU) or other forms of processing units having data processing capabilities and / or instruction execution capabilities, and may control other components in the electronic device to perform desired functions. In one embodiment of the present disclosure, the processor is used to run the computer-readable instructions stored in the memory.

[0105] Those skilled in the art should be able to understand that in order to solve the technical problem of how to obtain a good user experience, the present embodiment may also include well-known structures such as a communication bus and an interface, and these well-known structures should also be included in the protection scope of the present disclosure.

[0106] For detailed description of this embodiment, reference may be made to the corresponding descriptions in the aforementioned embodiments, which will not be repeated here.

[0107] Example 6

[0108] This embodiment provides a non-transitory computer-readable storage medium, which stores computer instructions, and the computer instructions are used to enable a computer to execute the pre-drilling evaluation method for vertical wellbore stability based on seismic data as described in any of Examples 1-3.

[0109] According to the computer-readable storage medium of the embodiment of the present disclosure, non-transitory computer-readable instructions are stored thereon. When the non-transitory computer-readable instructions are executed by a processor, all or part of the steps of the above-mentioned methods of each embodiment of the present disclosure are executed.

[0110] The above-mentioned computer-readable storage media include, but are not limited to: optical storage media (e.g., CD-ROM and DVD), magneto-optical storage media (e.g., MO), magnetic storage media (e.g., magnetic tape or mobile hard disk), media with built-in rewritable non-volatile memory (e.g., memory card) and media with built-in ROM (e.g., ROM box).

[0111] The embodiments of the present invention have been described above, and the above description is exemplary, not exhaustive, and is not limited to the disclosed embodiments. Many modifications and changes will be apparent to those skilled in the art without departing from the scope and spirit of the described embodiments.

Claims

1. A pre-drilling evaluation method for vertical wellbore stability based on seismic data. It is characterized in that include: Acquire relevant data of drilling design before drilling the target well, wherein the relevant data includes mud density; Based on the pre-stack and post-stack seismic data of the target well area, pre-stack and post-stack seismic inversion is carried out to obtain the formation elastic parameters at the target well location; Calculate the formation pressure and ground stress parameters at the target well location based on the obtained formation elastic parameters; Obtaining strength parameters, cohesion and internal friction angle of formation rock at the target well location through rock physics test experiments or based on the formation elastic parameters; Using the mud density and the formation pressure and ground stress parameters, numerical simulation of wellbore stability around the well is carried out to obtain the magnitude of vertical stress, tangential stress and radial stress at different directions around the well; Analyze the magnitude relationship of vertical stress, tangential stress and radial stress at different directions around the well to determine the tensile and shear failures that may occur around the well during drilling and complete the pre-drilling evaluation of the wellbore stability.

2. The method for pre-drilling evaluation of vertical wellbore stability based on seismic data according to claim 1, It is characterized in that Based on the pre-stack and post-stack seismic data of the target well area, pre-stack and post-stack seismic inversion is carried out to obtain the formation elastic parameters at the target well location, including: Collect pre-stack and post-stack seismic data of the target well area, conduct pre-stack and post-stack seismic inversion, and obtain three-dimensional data of P-wave velocity, S-wave velocity, and density; The formation elastic parameters are calculated based on the obtained three-dimensional data of P-wave velocity, S-wave velocity and density and on the basis of rock physics relationships.

3. The method for pre-drilling evaluation of vertical wellbore stability based on seismic data according to claim 2, It is characterized in that The formation elastic parameters include Young's modulus and Poisson's ratio.

4. The method for pre-drilling evaluation of vertical wellbore stability based on seismic data according to claim 3, It is characterized in that The step of calculating the formation pressure and ground stress parameters at the target well location based on the obtained formation elastic parameters includes: Based on the longitudinal wave velocity, the Young's modulus, the Poisson's ratio and the anisotropy parameters, the formation pressure prediction model and the ground stress prediction model are used to carry out formation pressure and ground stress prediction based on seismic data to obtain the magnitude and direction of the ground stress and the formation pressure from shallow to deep formations of the target well.

5. The method for pre-drilling evaluation of vertical wellbore stability based on seismic data according to claim 4, It is characterized in that The geostress includes vertical principal stress, maximum horizontal principal stress and lowest horizontal principal stress.

6. The method for pre-drilling evaluation of vertical wellbore stability based on seismic data according to claim 1, It is characterized in that The step of obtaining the strength parameters, cohesion and internal friction angle of the formation rock at the target well location through rock physics test experiments or based on the formation elastic parameters includes: Based on rock physics experimental analysis or rock physics experimental empirical parameters, the strength parameters, cohesion and internal friction angle of the formation rock are given; Alternatively, based on the formation elastic parameters, the strength parameters, cohesion and internal friction angle of the formation rock are calculated through rock physical relationships.

7. An electronic device, It is characterized in that The electronic device comprises: at least one processor; and, a memory communicatively connected to the at least one processor; wherein, The memory stores instructions that can be executed by the at least one processor, and the instructions are executed by the at least one processor so that the at least one processor can execute the pre-drilling evaluation method for vertical wellbore stability based on seismic data as described in any one of claims 1-6.

8. A non-transitory computer-readable storage medium, It is characterized in that The non-transitory computer-readable storage medium stores computer instructions, which are used to enable a computer to execute the pre-drilling evaluation method for vertical wellbore stability based on seismic data as described in any one of claims 1-6.

9. A pre-drilling evaluation device for vertical wellbore stability based on seismic data. It is characterized in that include: A drilling data acquisition module is used to acquire relevant data of the drilling design before drilling the target well, wherein the relevant data includes mud density; The elastic parameter calculation module is used to carry out pre-stack and post-stack seismic inversion based on the pre-stack and post-stack seismic data of the target well work area to obtain the formation elastic parameters at the target well location; A geostress calculation module, used to calculate the formation pressure and geostress parameters at the target well location based on the obtained formation elastic parameters; A rock strength parameter calculation module is used to obtain the strength parameters, cohesion and internal friction angle of the formation rock at the target well location through rock physics test experiments or based on the formation elastic parameters; A simulation calculation module is used to carry out numerical simulation of wellbore stability around the well using the mud specific gravity and the formation pressure and ground stress parameters, and obtain the magnitude of vertical stress, tangential stress and radial stress at different directions around the well; The evaluation module is used to analyze the magnitude relationship of vertical stress, tangential stress and radial stress at different locations around the well to determine the tensile and shear failures that may occur around the well during drilling and complete the pre-drilling evaluation of the wellbore stability.

10. The pre-drilling evaluation device for vertical wellbore stability based on seismic data according to claim 9, It is characterized in that Based on the pre-stack and post-stack seismic data of the target well area, pre-stack and post-stack seismic inversion is carried out to obtain the formation elastic parameters at the target well location, including: Collect pre-stack and post-stack seismic data of the target well area, conduct pre-stack and post-stack seismic inversion, and obtain three-dimensional data of P-wave velocity, S-wave velocity, and density; The formation elastic parameters are calculated based on the obtained three-dimensional data of P-wave velocity, S-wave velocity and density and on the basis of rock physics relationships.