Continental facies shale rock physical modeling method and device, electronic equipment and medium
By combining DEM, SCA and Backus averaging technologies, a petrophysical model of terrestrial shale was established, which solved the problem of difficult to accurately describe and analyze shale reservoirs in the existing technology, and improved the applicability and prediction accuracy of the model.
Patent Information
- Application Number
- CN202311586265.X
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2023-11-24
- Publication Date
- 2025-05-27
AI Technical Summary
The existing technology has not yet developed an effective method for terrestrial shale rock physical modeling, and it is difficult to accurately describe and analyze the structural characteristics and parameters of shale reservoirs.
By inputting mineral components and content and physical properties parameters based on core experiments, combined with DEM model, SCA model and anisotropic Backus average technology, the elastic parameters of clay, organic matter and brittle mineral framework are calculated to establish a suitable anisotropic shale petrophysical model.
The applicability of the shale reservoir rock physical model is improved, and the reservoir dessert prediction and sensitive parameter analysis can be more accurately guided, and the model prediction results are more consistent with the experimental data.
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Figure CN120046288A_ABST
Abstract
Description
Technical Field
[0001] The present invention relates to the field of shale petrophysics, and more specifically, to a method, device, electronic device and medium for modeling the petrophysics of continental shale rocks. Background Art
[0002] Continental shale reservoirs are characterized by complex lithology, strong heterogeneity, and the development of thin interlayers. The complex mineral composition and microscopic pore space structure usually exhibit VTI anisotropy. Understanding the structural characteristics of shale reservoirs and obtaining reservoir parameters, petrophysical modeling is a key step in reservoir description and analysis. In strongly anisotropic continental shale, it is important to comprehensively consider the clay content, its anisotropy and orientation arrangement for the influence on shale elastic parameters and anisotropy. How to construct a petrophysical model suitable for the target area has important research significance for later reservoir sweet spot prediction and sensitive parameter analysis.
[0003] Currently, there is a need to develop a method for modeling the petrophysics of continental shale rocks.
[0004] The information disclosed in the background art section of the present invention is only intended to deepen the understanding of the general background art of the present invention, and should not be regarded as an admission or any form of implication that this information constitutes the prior art known to those skilled in the art. Summary of the Invention
[0005] The present invention provides a method, device, electronic device and medium for modeling the petrophysics of continental shale rocks, which can effectively improve the applicability of the petrophysical model of shale reservoirs under the joint constraints of various factors and can better guide reservoir sweet spot prediction.
[0006] In a first aspect, an embodiment of the present disclosure provides a method for modeling the petrophysics of continental shale rocks, including:
[0007] Based on core experiments, obtain the mineral composition, content and physical property parameters of the sample as the input parameters of the petrophysical model;
[0008] Calculate the elastic parameters of the clay mineral anisotropy element, and add clay pores to the oriented clay matrix through the DEM model to obtain a clay skeleton;
[0009] Convert the mass fraction of organic matter into the volume fraction of organic matter through a conversion formula, and add organic matter pores to the organic matter through the DEM model to obtain an organic matter skeleton;
[0010] Obtain a brittle mineral skeleton through the SCA model and the DEM model;
[0011] The organic matter clay complex and the brittle mineral skeleton are mixed through anisotropic Backus averaging to calculate the effective elastic parameters of dry rock, and a shale rock physics model is obtained.
[0012] As a specific implementation manner of the embodiment of the present disclosure, the elastic parameters of the clay mineral anisotropic element are:
[0013]
[0014] Among them, cdi represents the degree of directional arrangement of clay minerals, is the elastic stiffness matrix when the clay minerals are randomly distributed, refers to the elastic parameter matrix corresponding to the case where the clay mineral particles are arranged in a directional arrangement, C V is the elastic stiffness matrix of clay.
[0015] As a specific implementation manner of the embodiment of the present disclosure, the DEM model is:
[0016]
[0017] Among them, ν is the volume content of the inclusions, I is the unit tensor, c DEM represents the equivalent medium stiffness tensor obtained through the DEM model, c i represents the stiffness tensor of the inclusions added to the matrix, is the stiffness tensor related to the shape of the inclusions.
[0018] As a specific implementation manner of the embodiment of the present disclosure, the conversion formula is:
[0019] V_toc = W_toc * K * ρ m / ρ o
[0020] Among them, V_toc is the volume fraction of organic matter; W_toc is the mass fraction of organic matter; K is the organic matter conversion coefficient; ρ m is the shale density, ρ o is the organic matter density.
[0021] As a specific implementation manner of the embodiment of the present disclosure, the SCA model is:
[0022]
[0023]
[0024] Among them, χ i is the volume content of the i-th medium, K i and μ i are the bulk modulus and shear modulus of the i-th medium, P*i and Q *i represents the geometry of the i-th medium.
[0025] As a specific implementation manner of the embodiments of the present disclosure, the brittle mineral skeleton is obtained through the SCA model and the DEM model, including:
[0026] The clay skeleton and the organic matter skeleton are mixed through the SCA model to obtain an organic clay complex;
[0027] The contents of carbonate rock, quartz, and pyrite are mixed through the SCA model to obtain the bulk modulus and shear modulus of the brittle mineral matrix;
[0028] The brittle pore fractures are added to the brittle mineral matrix through the DEM model to obtain a brittle mineral skeleton.
[0029] As a specific implementation manner of the embodiments of the present disclosure, the effective elastic parameters of dry rock are:
[0030]
[0031]
[0032]
[0033] Among them,
[0034] Secondly, the embodiments of the present disclosure also provide a terrestrial shale rock physics modeling device, including:
[0035] An input module, based on core experiments, obtains the mineral components and contents, and physical property parameters of the sample, as the input parameters of the rock physics model;
[0036] A first calculation module, calculates the elastic parameters of the clay mineral anisotropic element, and adds clay pores to the oriented clay matrix through the DEM model to obtain a clay skeleton;
[0037] A second calculation module, converts the organic matter mass fraction to the organic matter volume fraction through a conversion formula, and adds organic matter pores to the organic matter through the DEM model to obtain an organic matter skeleton;
[0038] A third calculation module, obtains a brittle mineral skeleton through the SCA model and the DEM model;
[0039] A modeling module, mixes the organic matter clay complex and the brittle mineral skeleton through anisotropic Backus averaging, calculates the effective elastic parameters of dry rock, and obtains a shale rock physics model.
[0040] As a specific implementation manner of an embodiment of the present disclosure, the elastic parameters of the clay mineral anisotropic element are as follows:
[0041]
[0042] Among them, cdi represents the degree of oriented arrangement of clay minerals, is the elastic stiffness matrix when the clay minerals are randomly distributed, refers to the elastic parameter matrix corresponding to the case where the clay mineral particles are arranged in an oriented manner, C V is the elastic stiffness matrix of clay.
[0043] As a specific implementation manner of an embodiment of the present disclosure, the DEM model is:
[0044]
[0045] Among them, ν is the volume content of the inclusions, I is the unit tensor, c DEM represents the equivalent medium stiffness tensor obtained through the DEM model, c i represents the stiffness tensor of the inclusions added to the matrix, is the stiffness tensor related to the shape of the inclusions.
[0046] As a specific implementation manner of an embodiment of the present disclosure, the conversion formula is:
[0047] V_toc = W_toc * K * ρ m / ρ o
[0048] Among them, V_toc is the organic matter volume fraction; W_toc is the organic matter mass fraction; K is the organic matter conversion coefficient; ρ m is the shale density, ρ o is the organic matter density.
[0049] As a specific implementation manner of an embodiment of the present disclosure, the SCA model is:
[0050]
[0051]
[0052] Among them, χ i is the volume content of the i-th medium, K i and μ i are the bulk modulus and shear modulus of the i-th medium, P *i and Q *i represent the geometric shape of the i-th medium.
[0053] As a specific implementation manner of the embodiments of the present disclosure, obtaining a brittle mineral skeleton through the SCA model and the DEM model includes:
[0054] Mixing the clay skeleton and the organic matter skeleton through the SCA model to obtain an organic clay complex;
[0055] Mixing the contents of carbonate rock, quartz, and pyrite through the SCA model to obtain the bulk modulus and shear modulus of the brittle mineral matrix;
[0056] Adding brittle pores and fractures to the brittle mineral matrix through the DEM model to obtain a brittle mineral skeleton.
[0057] As a specific implementation manner of the embodiments of the present disclosure, the effective elastic parameters of dry rock are:
[0058]
[0059]
[0060]
[0061] Wherein,
[0062] Thirdly, the embodiments of the present disclosure further provide an electronic device, which includes:
[0063] A memory storing executable instructions;
[0064] A processor, the processor running the executable instructions in the memory to implement the above-mentioned continental shale rock physics modeling method.
[0065] Fourthly, the embodiments of the present disclosure further provide a computer-readable storage medium, which stores a computer program, and when the computer program is executed by a processor, the above-mentioned continental shale rock physics modeling method is implemented.
[0066] The beneficial effects are as follows:
[0067] The present invention aims at the cores of shale, considering the influence of the mineral components, clay pores, organic matter pores, brittle pores and fractures of shale reservoirs, and uses the self-consistent model SCA, anisotropic DEM and anisotropic Backus averaging to establish a suitable anisotropic shale rock physics model. The results predicted by the model are in good agreement with the experimental data, and can provide theoretical guidance for predicting sweet spot parameters of later reservoirs.
[0068] The methods and apparatuses of the present invention have other characteristics and advantages that will be apparent from, or will be described in detail in, the accompanying drawings and the subsequent detailed description incorporated herein. The accompanying drawings and the detailed description are used together to explain the specific principles of the present invention. Description of the Drawings
[0069] The above and other objects, features, and advantages of the present invention will become more apparent by describing the exemplary embodiments of the present invention in more detail in conjunction with the accompanying drawings, in which like reference numerals generally represent like components in the exemplary embodiments of the present invention.
[0070] Figure 1 A flowchart showing the steps of a method for modeling the petrophysics of continental shale according to an embodiment of the present invention is shown.
[0071] Figure 2a 、 Figure 2b 、 Figure 2c 、 Figure 2d Schematic diagrams showing the comparison results of the experimental test velocity data Vp H 、Vs H 、Vp V 、Vs V and the model template according to an embodiment of the present invention are shown respectively.
[0072] Figure 3a 、 Figure 3b Schematic diagrams showing the comparison results of the experimental test anisotropy parameters γ, ε and the model template according to an embodiment of the present invention are shown respectively.
[0073] Figure 4 A block diagram of an apparatus for modeling the petrophysics of continental shale according to an embodiment of the present invention is shown.
[0074] Description of the Reference Numerals:
[0075] 201, input module; 202, first calculation module; 203, second calculation module; 204, third calculation module; 205, modeling module. Detailed Description of the Embodiments
[0076] The preferred embodiments of the present invention will be described in more detail below. Although the preferred embodiments of the present invention are described below, 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.
[0077] To facilitate understanding of the solutions and effects of the embodiments of the present invention, six specific application examples are given below. Those skilled in the art should understand that this example is only for facilitating the understanding of the present invention, and any specific details are not intended to limit the present invention in any way.
[0078] Example 1
[0079] Figure 1 The flowchart shows the steps of a continental shale rock physics modeling method according to an embodiment of the present invention.
[0080] As Figure 1 shown, the continental shale rock physics modeling method includes: Step 101, obtaining the mineral composition and content, and physical property parameters of the sample based on core experiments as the input parameters of the rock physics model; Step 102, calculating the elastic parameters of the clay mineral anisotropic element, adding clay pores to the oriented clay matrix through the DEM model to obtain a clay skeleton; Step 103, converting the organic matter mass fraction to the organic matter volume fraction through a conversion formula, and adding organic matter pores to the organic matter through the DEM model to obtain an organic matter skeleton; Step 104, obtaining a brittle mineral skeleton through the SCA model and the DEM model; Step 105, mixing the organic matter-clay complex and the brittle mineral skeleton through anisotropic Backus averaging, calculating the effective elastic parameters of the dry rock, and obtaining a shale rock physics model.
[0081] In one example, the elastic parameters of the clay mineral anisotropic element are:
[0082]
[0083] where cdi represents the degree of orientation of clay minerals, is the elastic stiffness matrix when the clay minerals are randomly distributed, refers to the elastic parameter matrix corresponding to the case where the clay mineral particles are oriented, and C V is the elastic stiffness matrix of clay.
[0084] In one example, the DEM model is:
[0085]
[0086] where ν is the volume content of the inclusions, I is the unit tensor, and c DEM represents the equivalent medium stiffness tensor obtained through the DEM model, and c i represents the stiffness tensor of the inclusions added to the matrix, is the stiffness tensor related to the shape of the inclusions.
[0087] In one example, the conversion formula is:
[0088] V_toc = W_toc * K * ρ m / ρ o
[0089] Among them, \(V_{toc}\) is the volume fraction of organic matter; \(W_{toc}\) is the mass fraction of organic matter; \(K\) is the conversion coefficient of organic matter; \(\rho\) m is the shale density, \(\rho\) o is the density of organic matter.
[0090] In one example, the SCA model is:
[0091]
[0092]
[0093] Among them, \(\chi\) i is the volume content of the \(i\)-th medium, \(K\) i and \(\mu\) i are the bulk modulus and shear modulus of the \(i\)-th medium, \(P\) *i and \(Q\) *i represent the geometry of the \(i\)-th medium.
[0094] In one example, through the SCA model and the DEM model, the brittle mineral skeleton obtained includes:
[0095] Mix the clay skeleton and the organic matter skeleton through the SCA model to obtain an organic clay complex;
[0096] Mix the contents of carbonate rock, quartz, and pyrite through the SCA model to obtain the bulk modulus and shear modulus of the brittle mineral matrix;
[0097] Add brittle pores and fractures to the brittle mineral matrix through the DEM model to obtain the brittle mineral skeleton.
[0098] In one example, the effective elastic parameters of dry rock are:
[0099]
[0100]
[0101]
[0102] Among them,
[0103] Specifically, based on core experiments, obtain the mineral components (minerals such as quartz, clay, carbonate rock, etc.) and contents, and physical property parameters (porosity, density) of the samples, and acquire the input parameters of the rock physics model.
[0104] Regarding clay mineral particles as anisotropic elements, the elastic parameters of clay minerals are calculated in combination with the orientation of clay minerals. The clay directional index CDI (Clay Directional Index) is introduced, and CDI represents the degree of oriented arrangement of clay minerals. CDI = 1 indicates that the clay minerals are completely oriented, and the elastic parameters of the clay medium are equal to the elastic parameters of the anisotropic elements of the clay minerals:
[0105]
[0106] It can be concluded from the microstructure that continental shale is mainly composed of clay pores, with a small amount of organic matter pores and intergranular pore spaces. Since clay mineral particles are regarded as anisotropic elements, the anisotropic equivalent model DEM is used to add clay pores to the oriented clay matrix. Then, the formula for the anisotropic equivalent theoretical model DEM is:
[0107]
[0108] where ν is the volume fraction of the inclusions, in decimal; I is the unit tensor, c DEM represents the equivalent medium stiffness tensor obtained through the DEM model, dimensionless; c i represents the stiffness tensor of the inclusions added to the matrix, dimensionless; is the stiffness tensor related to the shape of the inclusions, dimensionless.
[0109] The organic matter mass fraction is converted into the organic matter volume fraction V_toc, and the conversion formula is:
[0110] V_toc = W_toc * K * ρ m / ρ o (3)
[0111] where V_toc is the organic matter volume fraction; W_toc is the organic matter mass fraction; K is the organic matter conversion coefficient; ρ m is the shale density, generally taken as 2.5 g / cm 3 , ρ o is the organic matter density, generally taken as 1.0 g / cm 3 ; The organic matter volume content is obtained from V organic = V_toc * V m . V m is the volume of the entire shale sample, regarded as 1.
[0112] Similarly, the organic matter pores are added to the organic matter using the anisotropic equivalent model DEM to obtain the organic matter skeleton; then, the clay skeleton and the organic matter skeleton are mixed together using the anisotropic equivalent model SCA to obtain the organic clay complex; the carbonate rock, quartz, and pyrite contents are mixed in proportion using the isotropic self-consistent model SCA to obtain the bulk modulus and shear modulus of the brittle mineral matrix. The SCA expression used is:
[0113]
[0114]
[0115] where χ i is the volume content of the i-th medium, K i and μ i are the bulk modulus and shear modulus of the i-th medium, P *i and Q *i represent the geometry of the i-th medium. The SCA model has been extended to the influence of inclusions with different shapes on the elastic parameters of rocks. The P and Q coefficients are the same as above. The SCA model has continuous distributions of multiple mineral components and pores and is suitable for the case where multiple matrices jointly serve as the rock background matrix.
[0116] The brittle pore-fractures are successively added to the brittle mineral matrix using the isotropic equivalent theory model DEM to form the brittle mineral skeleton.
[0117] Considering the development of laminations in continental shale, the anisotropic Backus average is used to mix the directionally arranged organic clay complex and the brittle mineral skeleton to calculate the effective elastic parameters of the dry rock.
[0118]
[0119] In the formula: C ij and are the elastic stiffness coefficients of the equivalent media before and after the Backus average, respectively; <·> represents the weighted average of the elastic parameters of the VTI thin layers within a certain depth window in the data.
[0120] To obtain the anisotropic parameters of the rock sample, due to the influence of the development of horizontal laminations in shale, it has the characteristics of transverse isotropy. This anisotropic rock physics equivalent model is called the VTI model, and the corresponding stiffness matrix is:
[0121]
[0122] When sampling the shale rock in the study area and conducting anisotropic parameter experiments, the acoustic velocity information of the rock sample in the vertical direction, horizontal direction, and 45° direction of the lamination can be obtained. That is, it can characterize the elastic parameters of the rock sample.
[0123]
[0124]
[0125]
[0126]
[0127] C 12 = C 11 -2C 66 (12)
[0128]
[0129] Combined with the anisotropic parameter expressions proposed by Thomsen (1986), the anisotropic parameters of the rock sample can be obtained:
[0130]
[0131]
[0132]
[0133] Combined with the experimental data, the constructed continental shale rock physics model is calibrated to obtain the shale rock physics model.
[0134] Example 2
[0135] The present invention also provides a device for modeling the rock physics of continental shale, including:
[0136] An input module, based on core experiments, obtains the mineral composition and content, and physical property parameters of the sample as the input parameters of the rock physics model;
[0137] A first calculation module, calculates the elastic parameters of the anisotropic elements of clay minerals, adds clay pores to the oriented clay matrix through the DEM model to obtain a clay skeleton;
[0138] A second calculation module, converts the mass fraction of organic matter into the volume fraction of organic matter through a conversion formula, adds organic matter pores to the organic matter through the DEM model to obtain an organic matter skeleton;
[0139] A third calculation module, obtains a brittle mineral skeleton through the SCA model and the DEM model;
[0140] A modeling module, mixes the organic matter-clay complex and the brittle mineral skeleton through anisotropic Backus averaging, calculates the effective elastic parameters of the dry rock, and obtains the shale rock physics model.
[0141] In one example, the elastic parameters of the clay mineral anisotropic element are as follows:
[0142]
[0143] where cdi represents the degree of orientation of clay minerals, is the elastic stiffness matrix when the clay minerals are randomly distributed, refers to the elastic parameter matrix corresponding to the case when the clay mineral particles are arranged in an oriented manner, C V is the elastic stiffness matrix of the clay.
[0144] In one example, the DEM model is as follows:
[0145]
[0146] where ν is the volume fraction of the inclusions, I is the unit tensor, c DEM represents the equivalent medium stiffness tensor obtained through the DEM model, c i represents the stiffness tensor of the inclusions added to the matrix, is the stiffness tensor related to the shape of the inclusions.
[0147] In one example, the conversion formula is as follows:
[0148] V_toc = W_toc * K * ρ m / ρ o
[0149] where V_toc is the volume fraction of organic matter; W_toc is the mass fraction of organic matter; K is the organic matter conversion coefficient; ρ m is the shale density, ρ o is the organic matter density.
[0150] In one example, the SCA model is as follows:
[0151]
[0152]
[0153] where χ i is the volume fraction of the i-th medium, K i and μ i are the bulk modulus and shear modulus of the i-th medium, P *i and Q *i represent the geometry of the i-th medium.
[0154] In one example, through the SCA model and the DEM model, the brittle mineral skeleton obtained includes:
[0155] Mix the clay skeleton and the organic matter skeleton through the SCA model to obtain an organic clay composite;
[0156] Mix the contents of carbonate rock, quartz, and pyrite through the SCA model to obtain the bulk modulus and shear modulus of the brittle mineral matrix;
[0157] Add brittle pore fractures to the brittle mineral matrix through the DEM model to obtain a brittle mineral skeleton.
[0158] In one example, the effective elastic parameters of dry rock are:
[0159]
[0160]
[0161]
[0162] Among them,
[0163] Specifically, based on core experiments, obtain the mineral components (minerals such as quartz, clay, carbonate rock, etc.) and contents, and physical property parameters (porosity, density) of the samples, and acquire the input parameters of the rock physics model.
[0164] Regard clay mineral particles as anisotropic elements, calculate the elastic parameters of clay minerals in combination with the orientation of clay minerals, introduce the clay mineral orientation index CDI (Clay Directional Index), and CDI represents the degree of oriented arrangement of clay minerals. CDI = 1 indicates that clay minerals are completely oriented, and the elastic parameters of the clay medium are equal to the elastic parameters of clay mineral anisotropic elements:
[0165]
[0166] It can be obtained from the microscopic structure that continental shale mainly consists of clay pores, a small amount of organic matter pores, and intergranular pore fractures. Since clay minerals are regarded as anisotropic elements, the anisotropic equivalent model DEM is used to add clay pores to the oriented clay matrix. Then, the formula of the anisotropic equivalent theoretical model DEM is:
[0167]
[0168] Among them, ν is the volume content of inclusions, a decimal; I is the unit tensor, c DEM represents the equivalent medium stiffness tensor obtained through the DEM model, dimensionless; c i represents the stiffness tensor of the inclusions added to the matrix, dimensionless; is the stiffness tensor related to the shape of the inclusions, dimensionless.
[0169] Convert the organic matter mass fraction to the organic matter volume fraction \(V_{toc}\), and the conversion formula is:
[0170] \(V_{toc}=W_{toc}\times K\times\rho\) m / \(\rho\) o (3)
[0171] where \(V_{toc}\) is the organic matter volume fraction; \(W_{toc}\) is the organic matter mass fraction; \(K\) is the organic matter conversion coefficient; \(\rho\) m is the shale density, generally taken as \(2.5\ g / cm\) 3 \(\rho\) o is the organic matter density, generally taken as \(1.0\ g / cm\) 3 ; The organic matter volume content is obtained from \(V\) organic \(=V_{toc}\times V\) m . \(V\) m is the volume of the entire shale sample, regarded as 1.
[0172] Similarly, use the anisotropic equivalent model DEM to add organic matter pores to the organic matter to obtain the organic matter skeleton; then, use the anisotropic equivalent model SCA to mix the clay skeleton and the organic matter skeleton together to obtain the organic clay complex; use the isotropic self-consistent model SCA to mix the carbonate rock, quartz, and pyrite contents in proportion to obtain the bulk modulus and shear modulus of the brittle mineral matrix. The SCA expression used is:
[0173]
[0174]
[0175] where \(\chi\) i is the volume content of the \(i\)-th medium, \(K\) i and \(\mu\) i are the bulk modulus and shear modulus of the \(i\)-th medium, \(P\) *i and \(Q\) *i represent the geometry of the \(i\)-th medium. The SCA model has been extended to the influence of inclusions of different shapes on the elastic parameters of rocks, and the \(P\) and \(Q\) coefficients are the same as above. The SCA model is for the continuous distribution of multiple mineral components and pores and is suitable for the case where multiple matrices jointly serve as the rock background matrix.
[0176] Use the isotropic equivalent theory model DEM to sequentially add brittle pores and fractures to the brittle mineral matrix to form a brittle mineral skeleton.
[0177] Considering the development of laminations in continental shales, use the anisotropic Backus average to mix the oriented organic clay complex and the brittle mineral skeleton to calculate the effective elastic parameters of the dry rock.
[0178]
[0179] Where: C ij and are the elastic stiffness coefficients of the equivalent media before and after the Backus average, respectively; <·> represents the weighted average of the elastic parameters of the VTI thin layers within a certain depth window in the data.
[0180] When obtaining the anisotropic parameters of rock samples, affected by the well-developed horizontal bedding of shale, it has the characteristics of transverse isotropy. This anisotropic rock physics equivalent model is called the VTI model, and the corresponding stiffness matrix is:
[0181]
[0182] When taking shale rock samples in the study area and conducting anisotropic parameter experiments, the acoustic velocity information of the rock samples in the vertical direction, horizontal direction, and 45° direction of the bedding can be obtained. That is, it can characterize the elastic parameters of the rock samples.
[0183]
[0184]
[0185]
[0186]
[0187] C 12 = C 11 - 2C 66 (12)
[0188]
[0189] Combined with the anisotropic parameter expressions proposed by Thomsen (1986), the anisotropic parameters of the rock samples can be obtained:
[0190]
[0191]
[0192]
[0193] Combined with the experimental data, the constructed continental shale rock physics model is calibrated to obtain the shale rock physics model.
[0194] Example 3
[0195] A rock physics model applicable to the target area is constructed based on the continental shale core data in a certain area. The prediction results of the model are in good agreement with the experimental data, verifying that the model has certain applicability.
[0196] Figure 2a 、 Figure 2b 、 Figure 2c 、 Figure 2d respectively show the experimental test velocity data Vp H 、Vs H 、Vp V 、Vs V and the schematic diagram of the comparison result with the model template.
[0197] Figure 3a 、 Figure 3b respectively show the schematic diagrams of the comparison results of the experimental test anisotropy parameters γ, ε and the model template according to an embodiment of the present invention.
[0198] The consistency between the two is relatively good, indicating that the method has certain feasibility.
[0199] Example 4
[0200] Figure 4 shows the block diagram of a continental shale rock physics modeling device according to an embodiment of the present invention.
[0201] As Figure 4 shown, the continental shale rock physics modeling device includes:
[0202] An input module, based on core experiments, obtains the mineral composition and content, and physical property parameters of the samples as the input parameters of the rock physics model;
[0203] A first calculation module, calculates the elastic parameters of the clay mineral anisotropic element, adds clay pores to the oriented clay matrix through the DEM model to obtain a clay skeleton;
[0204] A second calculation module, converts the organic matter mass fraction into the organic matter volume fraction through a conversion formula, adds organic matter pores to the organic matter through the DEM model to obtain an organic matter skeleton;
[0205] A third calculation module, obtains a brittle mineral skeleton through the SCA model and the DEM model;
[0206] A modeling module, mixes the organic matter-clay complex and the brittle mineral skeleton through anisotropic Backus averaging, calculates the effective elastic parameters of the dry rock, and obtains a shale rock physics model.
[0207] As an optional solution, the elastic parameters of the clay mineral anisotropic element are:
[0208]
[0209] Among them, cdi represents the degree of oriented arrangement of clay minerals. is the elastic stiffness matrix when the clay minerals are randomly distributed. refers to the elastic parameter matrix corresponding to the case where the clay mineral particles are oriented, C V is the elastic stiffness matrix of the clay.
[0210] As an alternative, the DEM model is:
[0211]
[0212] Among them, ν is the volume content of the inclusions, I is the unit tensor, c DEM represents the equivalent medium stiffness tensor obtained through the DEM model, c i represents the stiffness tensor of the inclusions added to the matrix. is the stiffness tensor related to the shape of the inclusions.
[0213] As an alternative, the conversion formula is:
[0214] V_toc = W_toc * K * ρ m / ρ o
[0215] Among them, V_toc is the organic matter volume fraction; W_toc is the organic matter mass fraction; K is the organic matter conversion coefficient; ρ m is the shale density, ρ o is the organic matter density.
[0216] As an alternative, the SCA model is:
[0217]
[0218]
[0219] Among them, χ i is the volume content of the i-th medium, K i and μ i are the bulk modulus and shear modulus of the i-th medium, P *i and Q *i represent the geometric shape of the i-th medium.
[0220] As an alternative, through the SCA model and the DEM model, obtaining the brittle mineral skeleton includes:
[0221] Mixing the clay skeleton and the organic matter skeleton through the SCA model to obtain an organic clay composite.
[0222] The volume modulus and shear modulus of the brittle mineral matrix are obtained by mixing the contents of carbonate rock, quartz, and pyrite through the SCA model;
[0223] The brittle pore fractures are added to the brittle mineral matrix through the DEM model to obtain a brittle mineral skeleton.
[0224] As an alternative, the effective elastic parameters of the dry rock are:
[0225]
[0226]
[0227]
[0228] Wherein,
[0229] Example 5
[0230] This embodiment provides an electronic device, which includes: a memory storing executable instructions; a processor that runs the executable instructions in the memory to implement the above-mentioned continental shale rock physics modeling method.
[0231] The electronic device according to an embodiment of the present disclosure includes a memory and a processor.
[0232] 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 products may include various forms of computer-readable storage media, such as volatile memory and / or non-volatile memory. The volatile memory may include, for example, random access memory (RAM) and / or cache memory, etc. The non-volatile memory may include, for example, read-only memory (ROM), hard disk, flash memory, etc.
[0233] The processor may be a central processing unit (CPU) or other forms of processing units with data processing capabilities and / or instruction execution capabilities, and may control other components in the electronic device to perform desired functions. In an embodiment of the present disclosure, the processor is used to run the computer-readable instructions stored in the memory.
[0234] Those skilled in the art should understand that, in order to solve the technical problem of how to obtain a good user experience effect, this embodiment may also include well-known structures such as communication buses and interfaces, and these well-known structures should also be included in the protection scope of the present disclosure.
[0235] For the detailed description of this embodiment, reference may be made to the corresponding descriptions in the foregoing embodiments, which will not be repeated here.
[0236] Example 6
[0237] This embodiment provides a computer-readable storage medium, which stores a computer program. When the computer program is executed by a processor, the above-mentioned continental shale rock physics modeling method is implemented.
[0238] According to the computer-readable storage medium of the embodiments of the present disclosure, non-temporary computer-readable instructions are stored thereon. When the non-temporary computer-readable instructions are run by a processor, all or part of the steps of the methods of the various embodiments of the present disclosure described above are executed.
[0239] The above computer-readable storage medium includes, but is not limited to: optical storage media (such as CD-ROMs and DVDs), magneto-optical storage media (such as MOs), magnetic storage media (such as magnetic tapes or external hard drives), media with built-in rewritable non-volatile memories (such as memory cards), and media with built-in ROMs (such as ROM cartridges).
[0240] Those skilled in the art should understand that the purpose of the above description of the embodiments of the present invention is only to exemplarily illustrate the beneficial effects of the embodiments of the present invention, and is not intended to limit the embodiments of the present invention to any of the examples given.
[0241] The various embodiments of the present invention have been described above. The above description is exemplary and not exhaustive, and is also not limited to the disclosed embodiments. Many modifications and variations will be apparent to those of ordinary skill in the art without departing from the scope and spirit of the described embodiments.
Claims
1. A physical modeling method for continental shale rocks, characterized in that, it includes: Based on core experiments, obtain the mineral composition, content, and physical property parameters of the sample as the input parameters of the rock physical model; Calculate the elastic parameters of the clay mineral anisotropic element, and add clay pores to the oriented clay matrix through the DEM model to obtain a clay skeleton; Convert the mass fraction of organic matter into the volume fraction of organic matter through a conversion formula, and add organic matter pores to the organic matter through the DEM model to obtain an organic matter skeleton; Obtain a brittle mineral skeleton through the SCA model and the DEM model; Mix the organic matter-clay complex and the brittle mineral skeleton through anisotropic Backus averaging, calculate the effective elastic parameters of the dry rock, and obtain the shale rock physical model.
2. The physical modeling method for continental shale rocks according to claim 1, wherein, the elastic parameters of the clay mineral anisotropic element are: wherein, cdi represents the degree of oriented arrangement of clay minerals, is the elastic stiffness matrix when the clay minerals are arranged in a random distribution, refers to the elastic parameter matrix corresponding to the case where the clay mineral particles are arranged in an oriented manner, C V is the elastic stiffness matrix of the clay.
3. The physical modeling method for continental shale rocks according to claim 1, wherein, the DEM model is: where ν is the volume fraction of the inclusions, I is the unit tensor, and c DEM represents the equivalent medium stiffness tensor obtained from the DEM model, and c i represents the stiffness tensor of the inclusions added to the matrix, is the stiffness tensor related to the shape of the inclusions.
4. The physical modeling method for continental shale rocks according to claim 1, wherein, the conversion formula is: V_toc = W_toc * K * ρ m / ρ o Among them, $V_{toc}$ is the volume fraction of organic matter; $W_{toc}$ is the mass fraction of organic matter; $K$ is the conversion coefficient of organic matter; $\rho$ m is the shale density, $\rho$ o is the organic matter density.
5. The physical modeling method for continental shale rocks according to claim 1, wherein, the SCA model is: where χ i is the volume fraction of the i-th medium, K i and μ i are the bulk modulus and shear modulus of the i-th medium, P *i and Q *i represent the geometry of the i-th medium.
6. The physical modeling method for continental shale rocks according to claim 1, wherein, obtaining a brittle mineral skeleton through the SCA model and the DEM model includes: Mix the clay skeleton and the organic matter skeleton through the SCA model to obtain an organic clay complex; Mix the contents of carbonate rock, quartz, and pyrite through the SCA model to obtain the bulk modulus and shear modulus of the brittle mineral matrix; Add brittle pores and fractures to the brittle mineral matrix through the DEM model to obtain a brittle mineral skeleton.
7. The physical modeling method for continental shale rocks according to claim 1, wherein, the effective elastic parameters of the dry rock are: Among them, 8. A physical modeling device for continental shale rocks, characterized in that, it includes: An input module, which obtains the mineral composition, content, and physical property parameters of the sample based on core experiments as the input parameters of the rock physical model; A first calculation module, which calculates the elastic parameters of the clay mineral anisotropic element, and adds clay pores to the oriented clay matrix through the DEM model to obtain a clay skeleton; A second calculation module, which converts the mass fraction of organic matter into the volume fraction of organic matter through a conversion formula, and adds organic matter pores to the organic matter through the DEM model to obtain an organic matter skeleton; A third calculation module, which obtains a brittle mineral skeleton through the SCA model and the DEM model; A modeling module, which mixes the organic matter-clay complex and the brittle mineral skeleton through anisotropic Backus averaging, calculates the effective elastic parameters of the dry rock, and obtains the shale rock physical model.
9. An electronic device, characterized in that, the electronic device includes: A memory, which stores executable instructions; A processor, which runs the executable instructions in the memory to implement the physical modeling method for continental shale rocks according to any one of claims 1-7.
10. A computer-readable storage medium, characterized in that, the computer-readable storage medium stores a computer program, and when the computer program is executed by a processor, it implements the continental shale rock physics modeling method described in any one of claims 1-7.