Three-dimensional deformation inversion and non-uniform deformation evaluation method based on regional stress disturbance

Abstract

The application discloses a three-dimensional deformation inversion and non-uniform deformation evaluation method based on regional pressure disturbance, collects regional scale multi-source data; constructs a two-dimensional pressure field model, simulates a pore pressure change process; constructs a layered vertical deformation calculation model, calculates vertical deformation of each stratum unit under the action of pressure disturbance; constructs a deformation transmission model along the depth direction, maps the vertical deformation to different depth positions, forms a three-dimensional vertical deformation field, and calculates a non-uniform deformation gradient field; compares and verifies the three-dimensional vertical deformation field with surface vertical deformation monitoring data, corrects three-dimensional vertical deformation field model parameters; and carries out engineering application analysis. Through the construction of the regional two-dimensional pressure field model, the layered vertical deformation calculation model and the verification mechanism with the monitoring data, the quantitative inversion of the underground multi-depth vertical deformation and the deformation gradient is realized, and reliable three-dimensional deformation information can be obtained under the historical and future injection-production working conditions, which is used for engineering safety evaluation.

Description

Technical Field

[0001] This invention relates to the field of deformation analysis and reservoir mechanics simulation technology in underground engineering, and in particular to a three-dimensional deformation inversion and non-uniform deformation assessment method based on regional pressure disturbance. Background Technology

[0002] In underground engineering activities such as oil and gas development, underground storage operation, geothermal extraction, and carbon dioxide sequestration, changes in pore pressure caused by injection or extraction can produce significant vertical deformations at different depths. These deformations can lead to wellbore bending, abnormal casing stress, and decreased stability of surface structures, thus having a significant impact on engineering safety.

[0003] Existing technologies typically rely on three-dimensional fully coupled geomechanical models to calculate formation deformation. However, these models are computationally intensive, making it difficult to run them multiple times at a scale of tens of kilometers, and they also cannot quickly analyze deformation differences under different injection and production schemes. Furthermore, traditional methods often focus on surface deformation or shallow response, lacking a quantitative description of the vertical deformation distribution and non-uniform deformation characteristics (including deformation gradients) at different depths. This makes it difficult to meet the multi-depth information requirements for wellbore integrity, casing deformation risk, or foundation stability analysis. In addition, existing technologies generally lack a technical system that can effectively utilize surface deformation monitoring data such as InSAR and GNSS to validate the model, leading to inconsistencies between simulation results and actual deformation, and making it difficult to obtain a reliable three-dimensional subsurface deformation field. In particular, there is a lack of a method to invert the multi-depth deformation evolution under historical injection and production processes at a regional scale, and to conduct safety assessments of future injection and production schemes based on the validated deformation field, leaving engineering decisions without reliable quantitative basis.

[0004] Therefore, there is an urgent need for a technical method that can efficiently calculate pressure disturbances at the regional scale, invert the three-dimensional deformation distribution at multiple depths underground, and can be verified by combining surface monitoring data, while also being able to identify non-uniform deformation characteristics, in order to support underground deformation reconstruction, scheme comparison and selection and engineering safety assessment. Summary of the Invention

[0005] To address the challenges of existing technologies in efficiently calculating pressure disturbances at a regional scale, obtaining multi-depth vertical deformation distributions, validating models using monitoring data, and further applying these methods to historical deformation inversion and future injection-production scheme safety analysis, this application proposes a three-dimensional deformation distribution inversion and non-uniform deformation assessment method based on regional pressure disturbances. This method achieves quantitative inversion of underground multi-depth vertical deformation and deformation gradients by constructing a regional two-dimensional pressure field model, a layered vertical deformation calculation model, and a verification mechanism with monitoring data. It can also obtain reliable three-dimensional deformation information under historical and future injection-production conditions for engineering safety assessment of wellbore, casing, and structure foundations.

[0006] The technical solution adopted in this invention is: A three-dimensional deformation inversion and non-uniform deformation assessment method based on regional pressure perturbation includes the following steps: S1. Acquire reservoir structure data, formation mechanical parameters, injection and production condition data, and surface vertical deformation monitoring data that describe the regional scale. S2. Construct a two-dimensional pressure field model that can reflect the influence of pore pressure changes caused by injection or extraction activities on formation deformation, and simulate the pore pressure change process. S3. Based on the pore pressure change obtained in step S2, construct a layered vertical deformation calculation model. According to the equivalent deformation parameters and layer thickness of strata at different depths, calculate the vertical deformation of each stratum unit under pressure disturbance, which serves as the basic input for the subsequent construction of the three-dimensional vertical deformation field. S4. Based on the vertical deformation of each stratum unit obtained in step S3, construct a deformation transfer model along the depth direction, map the vertical deformation to different depth positions to form a three-dimensional vertical deformation field, and calculate the non-uniform deformation gradient field on this basis. S5. Compare and verify the three-dimensional vertical deformation field obtained in step S4 with the surface vertical deformation monitoring data, and correct the parameters of the three-dimensional vertical deformation field model according to the verification results to ensure the rationality of its spatial distribution and deformation amplitude. S6. Based on the three-dimensional vertical deformation field corrected in step S5 and its corresponding non-uniform deformation gradient field, conduct engineering application analysis.

[0007] In the above scheme, in step S1, the reservoir structure data includes reservoir burial depth, thickness, and spatial distribution characteristics; the formation mechanical parameters include formation elastic modulus, Poisson's ratio, porosity coefficient, permeability, and the constraint characteristics of the overburden; the injection and production condition data include well location distribution, injection or production volume, bottom hole pressure change curves, and production sequence; and the surface vertical deformation monitoring data includes multi-temporal surface vertical deformation information obtained by InSAR, GNSS, or leveling.

[0008] In the above scheme, the specific method of step S2 is as follows: based on the injection or extraction conditions, a two-dimensional pressure field model at the scale of the study area is constructed through numerical simulation to simulate the spatiotemporal evolution of pressure disturbance in the study area and obtain the regional pore pressure change distribution characteristics at different time nodes.

[0009] In the above scheme, in step S3, the vertical deformation of the strata at different depths is characterized by the functional relationship between pressure disturbance and stratum deformation parameters, expressed as follows: i ( ,y, )=C m,i Δ ( ,y, ) h i (x,y) in, i ( ,y, ) represents the vertical deformation of the i-th layer in the z-direction, where z is the depth direction; x, y represent the coordinate positions in the planar coordinate system; and t represents time. ( ,y, () represents the change in pore pressure; h i (x,y) represents the reservoir thickness of the i-th layer; i=1,2…N, where N is the number of reservoirs in the depth direction; The equivalent deformation coefficient of the i-th layer, determined by the rock physical properties, is expressed as:

[0010] in, Let be the Biot coefficient of the i-th rock layer. Let be the elastic modulus of the i-th rock layer.

[0011] In the above scheme, when the study area contains multiple reservoirs or multiple deformable layers, the total vertical deformation is obtained by layer-by-layer stacking along the depth direction:

[0012] in, It represents the total vertical deformation of a reservoir or formation unit.

[0013] In the above scheme, the method for constructing the three-dimensional vertical deformation field in step S4 is as follows: Construct a deformation transfer function in the depth direction. To characterize the constraint relationships, stiffness differences, and deformation attenuation laws among strata at different depths, the three-dimensional vertical deformation field is expressed as:

[0014] in, Indicates position ,time The vertical deformation; The deformation transfer function along the depth direction is used to characterize the attenuation and distribution of reservoir deformation as it is transmitted upwards or downwards. It represents the total vertical deformation of a reservoir or formation unit; In the case of multiple reservoirs, it can be further written as:

[0015] in, For the first The deformation transfer function corresponding to each reservoir is used to describe the influence of the reservoir on strata at different depths.

[0016] In the above scheme, an exponential decay form is used to construct the deformed transfer function. For the th One reservoir, its burial depth is The corresponding deformation transfer function is expressed as:

[0017] in, Indicates the first The burial depth of each reservoir; This represents the attenuation coefficient related to the thickness, stiffness, and interlayer constraints of the overburden layer; Indicates the target depth coordinates.

[0018] In the above scheme, in step S4, the non-uniform deformation gradient field is expressed as:

[0019] in, This represents the non-uniform deformation gradient vector of the three-dimensional vertical deformation field in the planar direction. Represents the three-dimensional vertical deformation field in the plane coordinate system. The vertical deformation at that location.

[0020] In the above scheme, the specific method in step S5 is as follows: perform sensitivity analysis on the equivalent deformation coefficient, deformation transfer function attenuation coefficient, reservoir burial depth and thickness and pressure disturbance characteristic parameters, disturb different parameter combinations in the multi-dimensional parameter space, identify the key control factors affecting the multi-depth deformation distribution by comparing the simulated deformation and the monitored deformation results, and obtain the optimal parameter combination for historical inversion.

[0021] In the above scheme, step S6, the engineering application analysis includes different injection and production schemes, formation deformation differences at different time scales, non-uniform deformation characteristics, wellbore integrity assessment, casing deformation risk identification, and regional structure foundation stability assessment.

[0022] The method of the present invention has the following beneficial effects: (1) By constructing a coupled framework of a two-dimensional pressure field model and a layered vertical deformation calculation model, this invention achieves efficient inversion of three-dimensional vertical deformation at the regional scale (tens of kilometers). Compared with the traditional three-dimensional fully coupled geomechanical model, the calculation efficiency is significantly improved, and it can support rapid comparison and analysis of multiple schemes.

[0023] (2) The present invention can obtain the vertical deformation distribution characteristics of reservoir layers, overburden, shallow and medium layers and surface at different depths, overcoming the limitations of existing technologies that only focus on surface deformation or single-depth response, and providing complete three-dimensional deformation information for multi-depth deformation analysis.

[0024] (3) By constructing a deformation transfer function, the present invention forwardly transfers the deformation at the reservoir depth to different depth locations, which can reasonably reflect the influence of the lithological differences, stiffness changes and interlayer constraints of the overburden on the deformation transfer, and the resulting three-dimensional deformation field has a clear physical meaning.

[0025] (4) Based on the three-dimensional vertical deformation field, the present invention further calculates the non-uniform deformation gradient field, which can quantitatively identify the location with a high degree of deformation concentration in the region, and provide a quantitative basis for the identification of wellbore bending and casing deformation risks and the assessment of the stability of the foundation of surface structures.

[0026] (5) This invention uses surface vertical deformation monitoring data such as InSAR, GNSS or leveling to compare and verify the calculation results, confirm the rationality of the spatial distribution and deformation amplitude of the three-dimensional deformation field, and improve the engineering credibility of the inversion results.

[0027] (6) By combining the evolution results of the three-dimensional vertical deformation field and its gradient at different times, this invention can analyze the variation law of deformation difference in the region over time, identify potential high-risk areas and their possible time intervals, and provide a basis for early warning and operation control of engineering risks.

[0028] (7) The method of the present invention is applicable to various injection or production conditions and formation deformation analysis at different time scales, such as oil and gas development, geothermal extraction, underground storage operation and carbon dioxide sequestration. It has good versatility and engineering applicability. Attached Figure Description

[0029] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0030] Figure 1 This is a flowchart of the three-dimensional deformation inversion and non-uniform deformation evaluation method based on regional pressure disturbance of the present invention; Figure 2 This is a schematic diagram of the well network distribution and injection-production time series curves in the study area in this embodiment of the invention; Figure 3This is a regional distribution map of the pore pressure change (ΔP) in the 5th and 10th years under the injection and extraction action in this embodiment of the invention; Figure 4 This is a three-dimensional vertical deformation distribution cloud map obtained based on pressure disturbance in an embodiment of the present invention; Figure 5 This is a vertical deformation slice image at different depths (four layers) in the 10th year of this invention embodiment; Figure 6 This is a vertical deformation gradient distribution diagram obtained in an embodiment of the present invention; Figure 7 This is a comparison and verification curve of the simulated results of vertical deformation of the ground surface at the selected monitoring points in this embodiment of the invention with the measured data. Detailed Implementation

[0031] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the invention.

[0032] It should be noted that the illustrations provided in the embodiments of the present invention are only schematic representations of the basic concept of the present invention. Therefore, the drawings only show the components related to the present invention and are not drawn according to the number, shape and size of the components in actual implementation. In actual implementation, the form, quantity and proportion of each component can be arbitrarily changed, and the layout of the components may also be more complex.

[0033] Furthermore, it should be noted that the features of the various embodiments of the present invention can be combined or integrated in whole or in part, and as those skilled in the art will understand, they can interact and operate in different ways. Each embodiment can be implemented independently of each other or in association with one another.

[0034] like Figure 1 As shown, this invention proposes a three-dimensional deformation inversion and non-uniform deformation evaluation method based on regional pressure disturbance, which specifically includes the following steps.

[0035] S1: Collect multi-source data at a regional scale Multi-source data covering the study area were collected to construct the parameter foundation required for pressure disturbance simulation, layered vertical deformation calculation, and model validation. This embodiment selects a two-dimensional planar region of approximately 20 km × 20 km as the calculation range, which includes the main production well network and its affected areas. To facilitate subsequent modeling, the computational domain was discretized into several spatial units. Each unit records its x and y positions in the planar coordinate system and includes relevant subsurface structure parameters, such as reservoir depth, reservoir thickness, interlayer structural characteristics, and overburden thickness, as shown in Table 1. The collected data also includes formation mechanical properties, injection and production conditions, and surface vertical deformation monitoring information to support two-dimensional pressure field calculation, layered deformation solution, and model parameter validation.

[0036] Table 1. Examples of typical structures and spatial parameters of regional model units.

[0037] The collected regional data mainly includes the following categories: Reservoir structure data includes the burial depth, thickness, and spatial distribution characteristics of reservoirs (or multiple reservoirs). In this embodiment, the reservoir burial depth in the study area is approximately 2.0–3.0 km, with a single-layer thickness of approximately 80–150 m. The reservoirs exhibit stable lateral distribution, with some local multi-layered structures. The collected data is used to describe the spatial configuration of the regional subsurface structure and to perform subsequent layered deformation calculations.

[0038] Formation mechanical parameters include elastic modulus, Poisson's ratio, porosity coefficient, permeability, and the constraint characteristics of the overburden. In this embodiment, formation permeability exhibits significant spatial heterogeneity and is used to characterize the mechanical response capability of different formations under pressure disturbances.

[0039] Injection and production data include well location distribution, injection or production volume, bottom hole pressure variation curves, and production timelines. In this embodiment, there are dozens of production wells in the study area, with a well network covering approximately 20 km × 20 km. Bottom hole pressure, injection / production intensity, and their time-varying information are extracted from multi-year injection and production records to drive regional pressure disturbance simulations. Figure 2 The well network distribution and injection-production time sequence curves of the study area in this embodiment are shown.

[0040] Surface vertical deformation monitoring data: This includes multi-temporal surface vertical deformation information obtained from InSAR, GNSS, or leveling measurements. This embodiment uses InSAR time-series monitoring data (covering the main injection and acquisition stages) to compare and verify the calculated surface vertical deformation.

[0041] Step S1 aims to construct the key dataset required for regional-scale pressure perturbation and multi-depth vertical deformation inversion, providing complete and effective input conditions for subsequent two-dimensional pressure field simulation, layered deformation calculation, three-dimensional deformation inversion, and model verification.

[0042] S2: Construct a two-dimensional pressure field model and simulate the pressure change process. In this embodiment, based on the injection or extraction conditions, a two-dimensional pressure field model at the scale of the study area is constructed through numerical simulation to simulate the spatiotemporal evolution of pressure disturbances within the study area and obtain the distribution characteristics of regional pore pressure changes at different time points.

[0043] The obtained pressure perturbation results can reflect the range of pressure changes, attenuation magnitude and temporal evolution characteristics caused by injection and production, and characterize the transmission behavior of injection and production perturbation at the regional scale.

[0044] To illustrate the calculation effect of this method, this embodiment selects the pore pressure changes in the 5th and 10th years of the injection and production process as examples, as shown in Figure 3. Figure 3(a) shows the pressure change distribution in the 5th year, and Figure 3(b) shows the pressure change distribution in the 10th year. It can be seen that as the injection and production process continues, the pressure drop area expands continuously, and the disturbance amplitude gradually increases.

[0045] The above pressure field results will serve as the input basis for subsequent calculations of layered vertical deformation.

[0046] S3: Calculate the vertical deformation of each layer After obtaining the spatiotemporal variation of the underground pressure field based on the simulation of injection and production conditions, the vertical deformation of strata at different depths is calculated to obtain the vertical deformation response of multi-layer structures under pressure disturbance. This calculation result forms the basic input for the subsequent construction of the three-dimensional vertical deformation field. Specifically, a formation elastic model or equivalent mechanical model can be used to calculate the vertical deformation of strata at each depth based on pressure changes and interlayer elastic parameters.

[0047] In one alternative implementation, the vertical deformation of strata at different depths can be characterized by a functional relationship between pressure disturbance and stratum deformation parameters. This relationship can be expressed as: i ( ,y, )= C m,i Δ ( ,y, ) h i (x,y) in, i ( ,y, ) represents the vertical deformation of the i-th layer in the z-direction, where z is the depth direction; x, y represent the coordinate positions in the planar coordinate system; and t represents time. ( ,y, () represents the change in pore pressure; h i (x,y) represents the reservoir thickness of the i-th layer; i=1,2…N, where N is the number of reservoirs in the depth direction. The equivalent deformation coefficient of the i-th layer, determined by the rock physical properties, can be expressed as:

[0048] in, Let be the Biot coefficient of the i-th rock layer. Let be the elastic modulus of the i-th rock layer. For example, when When, the corresponding elastic modulus can be taken as (Right now (This is used for example calculations.) In engineering applications, the equivalent deformation coefficient... The value can be determined based on physical parameters such as the elastic modulus, Poisson's ratio, and porosity elasticity of the reservoir rock. To illustrate the reasonable magnitude of this parameter under different lithological conditions, Table 2 provides examples of the equivalent deformation coefficient range for several lithologies. The specific value can be selected according to the actual engineering conditions.

[0049] Table 2. Range of rock physical properties and equivalent deformation coefficients for different reservoirs (illustrated)

[0050] The above relationship describes the vertical deformation response of formations at different depths under pressure disturbance. When the study area contains multiple reservoirs or multiple deformable layers, the total vertical deformation can be obtained by layer-by-layer stacking along the depth direction:

[0051] in, This represents the total vertical deformation of a reservoir or formation unit. This layered stacking model can characterize the contribution of pressure disturbances at different depths to the overall vertical deformation.

[0052] It should be noted that this embodiment demonstrates the numerical results using a single reservoir scenario, corresponding to the case where N=1 in the aforementioned general model. When the study area contains multiple reservoirs or deformable layers, it is only necessary to determine the equivalent deformation coefficient and layer thickness of each layer separately, calculate the vertical deformation of each layer layer by layer, and then superimpose them according to the above formula to obtain the total vertical deformation. The calculation process of this general model is consistent with the single-layer case, the only difference being that the parameters need to be obtained and solved separately for each layer.

[0053] S4: Constructing the three-dimensional vertical deformation field and the non-uniform deformation gradient field Obtain the vertical deformation of each reservoir or formation unit. and total vertical deformation Next, it is necessary to further construct the three-dimensional vertical deformation distribution of the underground profile in the z-direction. This embodiment adopts the idea of ​​layered deformation transfer, through a deformation transfer function. The process of reservoir deformation being transferred to the overburden and surface is described, thus obtaining a three-dimensional vertical deformation field.

[0054] (1) Construction of the three-dimensional vertical deformation field Construct a deformation transfer function in the vertical direction. This is used to characterize the constraint relationships, stiffness differences, and deformation attenuation patterns between strata at different depths. The three-dimensional vertical deformation field can be expressed as:

[0055] in, Indicates position ,time The vertical deformation; It represents the deformation transfer function along the depth direction, used to characterize the attenuation and distribution law when reservoir deformation is transmitted upward (or downward).

[0056] In the case of multiple reservoirs, it can be further written as:

[0057] in, For the first The deformation transfer function corresponding to each reservoir is used to describe the influence of the reservoir on strata at different depths.

[0058] When deformation from deep reservoirs (approximately 2–4 km) subjected to pressure disturbance propagates towards the surface, it exhibits significant attenuation due to differences in overburden lithology, lateral constraints, and variations in formation stiffness. This attenuation pattern is consistent with the displacement kernel function form in multilayer elastic theory. This embodiment employs an exponential attenuation form to construct the deformation transfer function. For the first... One reservoir, its burial depth is The corresponding deformation transfer function can be expressed as:

[0059] in, Indicates the first The burial depth of each reservoir; This represents the attenuation coefficient related to the thickness, stiffness, and interlayer constraints of the overburden layer; Represents the target depth coordinates (available on the ground). ).

[0060] The three-dimensional vertical deformation field can then be written as:

[0061] When only a single reservoir exists, the above equation simplifies to:

[0062] in, and These represent the vertical deformation and burial depth of the reservoir, respectively.

[0063] This exponential transfer function can reasonably reflect the attenuation characteristics of deep deformation propagating to the surface, and is suitable for engineering scenarios with relatively homogeneous overburden and large regional scale.

[0064] This embodiment uses the simplified single reservoir method described above for calculation demonstration, such as... Figure 4 As shown, the constructed three-dimensional deformation field can reflect the deformation intensity distribution and spatial differences within the region. For the general case involving multiple reservoirs, each reservoir corresponds to an independent deformation transfer function and attenuation coefficient. The three-dimensional vertical deformation field is obtained by weighted superposition of the contributions from each reservoir. The implementation process of this multi-layer model is completely consistent with the single-layer case; it only requires repeating the above calculations for each reservoir and superimposing the contributions from each layer. Therefore, the single-layer example in this embodiment can be regarded as a specific manifestation of the multi-layer general model under the condition of N=1.

[0065] In other implementations, the deformation transfer function Alternatively, piecewise linear models, transfer models based on the ratio of elastic moduli, or empirical functions obtained through numerical fitting can be used, depending on engineering requirements, to characterize the deformation distribution law under conditions of multi-layer structures or abrupt stiffness changes. This application addresses... The specific form of expression is not limited; any expression that can reasonably reflect the deformation transmission characteristics in the depth direction can be used.

[0066] To illustrate the differences in deformation at different depths, this embodiment provides multi-depth deformation slice images at selected times, such as... Figure 5 As shown, this is used to illustrate the difference in deformation amplitude between the deep and shallow parts and the spatial non-uniformity.

[0067] (2) Construction of non-uniform deformation gradient field In obtaining Subsequently, to identify non-uniform deformation characteristics within the region and further assess the deformation risk of the strata and structures, this invention calculates the spatial gradient of the deformation field, defined as:

[0068] in, This represents the non-uniform deformation gradient vector of the three-dimensional vertical deformation field in the planar direction. This represents the vertical deformation of the three-dimensional vertical deformation field at the plane coordinates (x, y).

[0069] Its gradient magnitude is expressed as:

[0070] Among them, | w| represents the magnitude (scalar) of the non-uniform deformation gradient, characterizing the spatial rate of change of surface deformation in the horizontal direction. For example... Figure 6 As shown, the gradient distribution can reveal the spatial concentration of differential deformation within a region, which is an important input for subsequent engineering application analysis.

[0071] S5: Model Validation and Historical Deformation Inversion Based on Monitoring Data After obtaining the three-dimensional vertical deformation calculation results, the model needs to be validated using monitoring data. Specifically, sensitivity analysis is performed on the equivalent deformation coefficient, deformation transfer function attenuation coefficient, reservoir burial depth and thickness, and pressure disturbance characteristic parameters. Different parameter combinations are perturbed in the multi-dimensional parameter space, and by comparing the simulated deformation and monitored deformation results, key control factors affecting the multi-depth deformation distribution are identified, and the optimal parameter combination for historical inversion is obtained.

[0072] The method of the present invention can be compared based on surface deformation cloud maps or time series of monitoring points.

[0073] In this embodiment, the available monitoring data is the time series of vertical deformation of the land surface at typical monitoring points (e.g., Figure 7 As shown in the figure, the verification is mainly based on time series. By comparing the consistency of the simulated and measured curves in terms of trend, amplitude and key moment changes, the equivalent deformation coefficient and deformation transfer function attenuation coefficient are adjusted so that the model can reflect the actual deformation characteristics.

[0074] In other implementations, when monitoring data provides regional surface deformation cloud maps, the model can be further constrained by comparing spatial distribution trends.

[0075] After parameter verification, deformation inversion can be performed on historical injection and production processes based on the optimal parameters to obtain three-dimensional vertical deformation fields at different time points. Specifically, the optimal parameter combination is input into historical injection or production time series to reconstruct the evolution process of regional pressure disturbance and multi-depth vertical deformation, and to obtain the three-dimensional underground deformation distribution at different time points in the past, which is used to verify the rationality and interpretability of the model.

[0076] S6: Conduct engineering application analysis In obtaining the three-dimensional vertical deformation field ( Figure 4 ), deformed slices at different depths ( Figure 5 ), deformation gradient distribution ( Figure 6 ) and deformation time series of typical monitoring points ( Figure 7 Following this, this embodiment demonstrates the applicability of the method in engineering deformation analysis. Three-dimensional vertical deformation field ( Figure 4 This can be used to identify the distribution of deformation intensity at a regional scale, providing a basis for identifying potentially significant deformation zones. Deformation slices at different depths ( Figure 5 This reveals the deformation differences and spatial non-uniformity between shallow and deep layers, and can be used to analyze the deformation contribution at different depths within multi-layered structures. Deformation gradient distribution ( Figure 6 This can be used to identify locations with significant non-uniform deformation within a region. Areas with larger gradients correspond to potentially locally stress-sensitive regions, providing a reference for stability assessments of underground engineering facilities or surface structures. Combined with deformation history curves of typical monitoring points ( Figure 7 This can further verify the model's ability to reflect the temporal characteristics of deformation.

[0077] After obtaining the validated three-dimensional vertical deformation field model, different injection and production schemes can be compared and analyzed according to engineering requirements. For any given injection and production scheme, its corresponding injection and production time series is input into the validated model, and the steps of pressure field calculation, layered vertical deformation calculation, and three-dimensional deformation inversion are repeated to obtain the three-dimensional vertical deformation field and non-uniform deformation gradient distribution corresponding to each scheme. Based on the above results, it can be used to evaluate the impact on the stability of wellbore bending sensitive sections, casing deformation risk areas, and surface structure foundations. It can also compare the differences in the impact of different production strategies on regional deformation, supporting engineering operation and scheme optimization. This application does not limit the specific application method and can be flexibly adopted according to actual needs.

[0078] This invention proposes a three-dimensional deformation inversion and non-uniform deformation assessment method based on regional pressure disturbance. It obtains the pressure distribution characteristics at a certain depth underground at different times through numerical simulation, and calculates the corresponding vertical deformation based on the pressure changes at that depth according to a given physical calculation relationship. Subsequently, the deformation at that depth is forward calculated to different depth locations through deformation transfer relationships, thereby obtaining a three-dimensional vertical deformation field including the surface. Since numerical simulation can obtain the pressure distribution at different times, it is possible to further develop a three-dimensional deformation evolution process at different times and depths. Surface deformation, as a practically monitorable quantity, is only used to verify the consistency of the calculation results. When the verification results show that the calculated deformation is reasonable in terms of spatial distribution and amplitude, it indicates that the model has engineering applicability. Based on this, non-uniform deformation gradients can be further calculated based on the three-dimensional deformation field to identify areas with large deformation differences and high potential engineering risks.

[0079] It should be noted that, depending on the implementation needs, the various steps / components described in this application can be broken down into more steps / components, or two or more steps / components or parts of the operation of steps / components can be combined into new steps / components to achieve the purpose of this invention.

[0080] The order of the steps in the above embodiments does not imply the order of execution. The execution order of each process should be determined by its function and internal logic, and should not constitute any limitation on the implementation process of the embodiments of this application.

[0081] It should be understood that those skilled in the art can make improvements or modifications based on the above description, and all such improvements and modifications should fall within the protection scope of the appended claims.

Claims

1. A three-dimensional deformation inversion and non-uniform deformation assessment method based on regional pressure perturbation, characterized in that, Includes the following steps: S1. Acquire reservoir structure data, formation mechanical parameters, injection and production condition data, and surface vertical deformation monitoring data that describe the regional scale. S2. Construct a two-dimensional pressure field model that can reflect the influence of pore pressure changes caused by injection or extraction activities on formation deformation, and simulate the pore pressure change process. S3. Based on the pore pressure change obtained in step S2, construct a layered vertical deformation calculation model. According to the equivalent deformation parameters and layer thickness of strata at different depths, calculate the vertical deformation of each stratum unit under pressure disturbance, which serves as the basic input for the subsequent construction of the three-dimensional vertical deformation field. S4. Based on the vertical deformation of each stratum unit obtained in step S3, construct a deformation transfer model along the depth direction, map the vertical deformation to different depth positions to form a three-dimensional vertical deformation field, and calculate the non-uniform deformation gradient field on this basis. S5. Compare and verify the three-dimensional vertical deformation field obtained in step S4 with the surface vertical deformation monitoring data, and correct the parameters of the three-dimensional vertical deformation field model according to the verification results to ensure the rationality of its spatial distribution and deformation amplitude. S6. Based on the three-dimensional vertical deformation field corrected in step S5 and its corresponding non-uniform deformation gradient field, conduct engineering application analysis.

2. The method for three-dimensional deformation inversion and non-uniform deformation evaluation based on regional pressure perturbation according to claim 1, characterized in that, In step S1, the reservoir structure data includes reservoir burial depth, thickness, and spatial distribution characteristics; Formation mechanical parameters include formation elastic modulus, Poisson's ratio, porosity coefficient, permeability, and the constraining characteristics of the overburden. Injection and production data include well location distribution, injection or production volume, bottom hole pressure variation curves, and production timeline. Surface vertical deformation monitoring data includes multi-temporal surface vertical deformation information obtained by InSAR, GNSS, or leveling.

3. The method for three-dimensional deformation inversion and non-uniform deformation evaluation based on regional pressure perturbation according to claim 1, characterized in that, The specific method of step S2 is as follows: Based on the injection or extraction conditions, a two-dimensional pressure field model at the scale of the study area is constructed through numerical simulation to simulate the spatiotemporal evolution of pressure disturbances in the study area and obtain the distribution characteristics of regional pore pressure changes at different time points.

4. The method for three-dimensional deformation inversion and non-uniform deformation evaluation based on regional pressure perturbation according to claim 1, characterized in that, In step S3, the vertical deformation of the strata at different depths is characterized by the functional relationship between pressure disturbance and stratum deformation parameters, expressed as follows: i ( ,and, )= C m,i Δ ( ,and, ) h i (x,y) in, i ( ,y, ) represents the vertical deformation of the i-th layer in the z-direction, where z is the depth direction; x, y represent the coordinate positions in the planar coordinate system; and t represents time. ( ,y, ) represents the change in pore pressure; h i (x,y) represents the reservoir thickness of the i-th layer; i=1,2…N, where N is the number of reservoirs in the depth direction; The equivalent deformation coefficient of the i-th layer, determined by the rock physical properties, is expressed as: in, Let be the Biot coefficient of the i-th rock layer. Let be the elastic modulus of the i-th rock layer.

5. The method for three-dimensional deformation inversion and non-uniform deformation evaluation based on regional pressure perturbation according to claim 4, characterized in that, When the study area contains multiple reservoirs or multiple deformable layers, the total vertical deformation is obtained by layer-by-layer stacking along the depth direction: in, It represents the total vertical deformation of a reservoir or formation unit.

6. The method for three-dimensional deformation inversion and non-uniform deformation evaluation based on regional pressure perturbation according to claim 1, characterized in that, In step S4, the method for constructing the three-dimensional vertical deformation field is as follows: Construct a deformation transfer function in the depth direction. To characterize the constraint relationships, stiffness differences, and deformation attenuation laws among strata at different depths, the three-dimensional vertical deformation field is expressed as: in, Indicates position ,time The vertical deformation; The deformation transfer function along the depth direction is used to characterize the attenuation and distribution of reservoir deformation as it is transmitted upwards or downwards. It represents the total vertical deformation of a reservoir or formation unit; In the case of multiple reservoirs, it can be further written as: in, For the first The deformation transfer function corresponding to each reservoir is used to describe the influence of the reservoir on strata at different depths.

7. The method for three-dimensional deformation inversion and non-uniform deformation evaluation based on regional pressure perturbation according to claim 6, characterized in that, The deformed transfer function is constructed using an exponential decay form, for the th One reservoir, its burial depth is The corresponding deformation transfer function is expressed as: in, Indicates the first The burial depth of each reservoir; This represents the attenuation coefficient related to the thickness, stiffness, and interlayer constraints of the overburden layer; Indicates the target depth coordinates.

8. The method for three-dimensional deformation inversion and non-uniform deformation evaluation based on regional pressure perturbation according to claim 1, characterized in that, In step S4, the non-uniform deformation gradient field is expressed as: in, This represents the non-uniform deformation gradient vector of the three-dimensional vertical deformation field in the planar direction. Represents the three-dimensional vertical deformation field in the plane coordinate system. The vertical deformation at that location.

9. The method for three-dimensional deformation inversion and non-uniform deformation evaluation based on regional pressure perturbation according to claim 1, characterized in that, The specific method in step S5 is as follows: perform sensitivity analysis on the equivalent deformation coefficient, deformation transfer function attenuation coefficient, reservoir burial depth and thickness and pressure disturbance characteristic parameters, disturb different parameter combinations in the multidimensional parameter space, identify the key control factors affecting the multi-depth deformation distribution by comparing the simulated deformation and the monitored deformation results, and obtain the optimal parameter combination for historical inversion.

10. The method for three-dimensional deformation inversion and non-uniform deformation evaluation based on regional pressure perturbation according to claim 1, characterized in that, In step S6, the engineering application analysis includes different injection and production schemes, formation deformation differences at different time scales, non-uniform deformation characteristics, wellbore integrity assessment, casing deformation risk identification, and regional structure foundation stability assessment.

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