Sandstone rock physical model construction method, electronic equipment, storage medium and device

Abstract

The invention provides a sandstone rock physical model construction method, electronic equipment, a storage medium and a sandstone rock physical model construction device. The sandstone rock physical model construction method comprises the following steps: setting a sandstone rock physical model comprising a quartz model and a clay mineral model; adding micropores containing non-flowable fluid into the clay mineral model by utilizing a KT model to obtain a pure shale model; based on a quartz model and a pure shale model, a Hashin-Shtrikman boundary average model is used for calculation to obtain a matrix mineral equivalent modulus; dry pores with certain connectivity are added into the matrix minerals by utilizing the relation between the effective stress and the aspect ratio of the pores, and the dry rock skeleton modulus is obtained; the free water and the bound water are mixed through a Wood equation, and the volume modulus of the mixed fluid is obtained through calculation; adding the bulk modulus of the mixed fluid into the dry rock skeleton modulus by using a Gassmann equation, and calculating to obtain a saturated rock modulus; and calculating to obtain a predicted longitudinal wave velocity and a predicted transverse wave velocity based on the saturated rock modulus. The problem that a conventional method is low in deep sandstone stratum speed prediction precision is solved.

Description

Technical Field

[0001] This invention belongs to the field of geophysics, and more specifically, relates to a method for constructing a physical model of sandstone, an electronic device, a storage medium, and a device. Background Technology

[0002] For deep sandstone formations with abnormally high pressure, the formation pressure coefficient is high, and it is difficult to ignore the influence of effective stress in the process of establishing rock physics models. Conventional rock physics models often do not consider the influence of effective stress, resulting in large errors in the velocity prediction of the established models, which cannot be well applied to the study area. Summary of the Invention

[0003] The purpose of this invention is to provide a method for constructing a sandstone rock physics model, an electronic device, a storage medium, and a device to solve the problem of large errors in the velocity prediction of deep sandstone formations in the study area by conventional rock physics models.

[0004] To achieve the above objectives, in a first aspect, the present invention provides a method for constructing a physical model of sandstone, comprising the following steps:

[0005] The physical model of the sandstone is defined to include a quartz model and a clay mineral model;

[0006] By adding micropores containing non-flowing fluids to a clay mineral model using the KT model, a pure shale model was obtained.

[0007] Based on the quartz model and the pure shale model, the equivalent modulus of the matrix minerals was calculated using the Hashin-Shtrikman boundary average model.

[0008] By utilizing the relationship between effective stress and pore aspect ratio, dry pores with a certain degree of connectivity are added to the matrix minerals to obtain the dry rock skeleton modulus.

[0009] The bulk modulus of the mixture was calculated by mixing free water and bound water using the Wood equation.

[0010] The saturated rock modulus was calculated by adding the bulk modulus of the mixed fluid to the dry rock skeleton modulus using the Gassmann equation.

[0011] Based on the saturated rock modulus, the predicted P-wave velocity and predicted S-wave velocity were calculated.

[0012] Optionally, the KT model expression is:

[0013]

[0014] In the formula, K * KTK is the equivalent medium bulk modulus. m K represents the bulk modulus of the rock matrix. i The bulk modulus of the pore inclusions. μ is the equivalent medium shear modulus. m μ is the shear modulus of the rock matrix. i denoted as the shear modulus of the pore inclusions; p and q are the influence coefficients characterizing different pore inclusions.

[0015] Optionally, the expression for the Hashin-Shtrikman boundary average model is:

[0016]

[0017] Where subscript 1 represents one mineral and subscript 2 represents another mineral; K is the bulk modulus of the corresponding mineral and μ is the shear modulus of the corresponding mineral; other parameters are the same as above; when quartz is defined as subscript 1 and the first clay mineral is defined as subscript 2, the calculated K HS± Upper limit of bulk modulus of mixed minerals, μ HS± This represents the upper limit of the shear modulus of the mixed minerals; when the first clay mineral is defined as subscript 1 and quartz as subscript 2, the calculated K is... HS± The lower limit of the bulk modulus of mixed minerals, μ HS± This represents the lower limit of the shear modulus of mixed minerals.

[0018] Optionally, the relationship between the effective stress and the porosity is expressed as follows:

[0019]

[0020] P c =P e +nP p ;

[0021]

[0022] Where α is the pore aspect ratio, α0 and x are given parameters, and P c For confining pressure, P e For effective stress, P p Where is the pore pressure, n is the effective stress coefficient, and K is the pore pressure. dry This represents the bulk modulus of dry rock.

[0023] Optionally, the expression for the Wood equation is:

[0024]

[0025] Among them, f i K represents the volume fraction of each component in the mixed fluid. if K represents the bulk modulus of each component in the fluid mixture.f For the bulk modulus of the mixed fluid, ρ i Let ρ be the density of each component in the fluid mixture, and ρ be the density of the fluid mixture.

[0026] Optionally, the Gassmann equation is expressed as:

[0027]

[0028] μ sat =μ dry ;

[0029] Among them, K sat μ is the bulk modulus of saturated rock. sat This represents the saturated rock shear modulus.

[0030] Optionally, the formula for calculating the predicted P-wave velocity of the saturated rock is:

[0031]

[0032] The formula for calculating the predicted shear wave velocity of the saturated rock is:

[0033]

[0034] Among them, v p For the predicted P-wave velocity of saturated rock, v s The predicted transverse wave velocity for saturated rocks.

[0035] In a second aspect, the present invention provides an electronic device, the electronic device comprising:

[0036] At least one processor; and,

[0037] A memory communicatively connected to the at least one processor; wherein,

[0038] The memory stores instructions that can be executed by the at least one processor to enable the at least one processor to perform the sandstone rock physical model construction method described in the first aspect.

[0039] Thirdly, the present invention provides a non-transitory computer-readable storage medium storing computer instructions for causing a computer to execute the sandstone rock physical model construction method described in the first aspect.

[0040] Fourthly, the present invention provides a sandstone rock physical model construction device, comprising:

[0041] The sandstone rock physical model setting module is used to set the sandstone rock physical model, including a quartz model and a clay mineral model.

[0042] The pure shale model construction module is used to add micropores containing non-flowing fluids to a clay mineral model using a KT model to obtain a pure shale model.

[0043] The matrix mineral equivalent modulus calculation module is used to calculate the matrix mineral equivalent modulus based on the quartz model and the pure shale model using the Hashin-Shtrikman boundary average model.

[0044] The dry rock skeleton modulus calculation module is used to add dry pores with a certain degree of connectivity to the matrix mineral based on the relationship between effective stress and pore aspect ratio to obtain the dry rock skeleton modulus.

[0045] The mixed fluid bulk modulus calculation module is used to calculate the bulk modulus of the mixed fluid by mixing free water and bound water using the Wood equation.

[0046] The saturated rock modulus calculation module is used to calculate the saturated rock modulus by adding the bulk modulus of the mixed fluid to the dry rock skeleton modulus using the Gassmann equation.

[0047] The predicted velocity calculation module is used to calculate the predicted P-wave velocity and predicted S-wave velocity based on the saturated rock modulus.

[0048] This invention provides a method for constructing a physical model of sandstone, the advantages of which are:

[0049] (1) Compared with conventional rock physics models, the effects of effective stress and fluid flow in pores are considered;

[0050] (2) Compared with conventional rock physics models, combining experimental data with rock physics models makes the rock physics model construction process more complete;

[0051] (3) Compared with the calculation results of conventional rock physics models, the calculation results of this method are more accurate;

[0052] (4) All tasks are accomplished using existing software platforms, which is convenient, fast, and highly practical, and can be promoted.

[0053] Other features and advantages of the present invention will be described in detail in the following detailed description section. Attached Figure Description

[0054] The above and other objects, features and advantages of the present invention will become more apparent from the more detailed description of exemplary embodiments of the invention in conjunction with the accompanying drawings, wherein the same reference numerals generally represent the same components in the exemplary embodiments of the invention.

[0055] Figure 1 A flowchart of the sandstone rock physical model construction method according to Embodiment 1 of the present invention is shown.

[0056] Figure 2 A flowchart of the sandstone rock physical model construction method according to Embodiment 2 of the present invention is shown.

[0057] Figure 3a The following is an example of a predicted shear wave velocity based on a conventional rock physics model, as shown in Embodiment 2 of the present invention.

[0058] Figure 3b The predicted transverse wave velocity based on the rock physics model of the effective stress effect in Embodiment 2 of the present invention is shown.

[0059] Figure 4a The diagram shows the error distribution of predicted shear wave velocity based on a conventional rock physics model in Embodiment 2 of the present invention.

[0060] Figure 4b The diagram shows the error distribution of predicted shear wave velocity using a rock physics model based on the influence of effective stress according to Embodiment 2 of the present invention.

[0061] Figure 5a The following is an example of a predicted P-wave velocity based on a conventional rock physics model, as shown in Embodiment 2 of the present invention.

[0062] Figure 5b The predicted P-wave velocity based on the rock physics model of the effective stress effect in Embodiment 2 of the present invention is shown.

[0063] Figure 6a The diagram shows the error distribution of predicted P-wave velocity based on a conventional rock physics model in Embodiment 2 of the present invention.

[0064] Figure 6b The diagram shows the error distribution of predicted P-wave velocity using a rock physics model based on the influence of effective stress according to Embodiment 2 of the present invention. Detailed Implementation

[0065] This invention proposes a method for constructing a sandstone rock physics model. It integrates the relationship between effective stress and pore aspect ratio, while also considering the influence of fluid flow between pores. This method effectively solves the problem of large error in the velocity prediction of deep sandstone strata in the study area by conventional rock physics models. By combining existing software tools and improving the technical methods and processes, it has achieved good application results in the study area and can be promoted.

[0066] Preferred embodiments of the invention will now be described in more detail. While preferred embodiments of the invention are described below, it should be understood that the invention can be implemented in various forms and should not be limited to the embodiments set forth herein. Rather, these embodiments are provided so that the invention will be thorough and complete, and will fully convey the scope of the invention to those skilled in the art.

[0067] Example 1:

[0068] See Figure 1 This disclosure provides a method for constructing a physical model of sandstone, comprising the following steps:

[0069] S1. The physical model of the sandstone is set to include a quartz model and a clay mineral model;

[0070] S2. Using the KT model, micropores containing non-flowing fluids are added to the clay mineral model to obtain a pure shale model;

[0071] In this step, the KT model expression is:

[0072]

[0073] In the formula, K * KT K is the equivalent medium bulk modulus. m K represents the bulk modulus of the rock matrix. i The bulk modulus of the pore inclusions. μ is the equivalent medium shear modulus. m μ is the shear modulus of the rock matrix. i denoted as the shear modulus of the pore inclusions; p and q are the influence coefficients characterizing different pore inclusions.

[0074] S3. Based on the quartz model and the pure shale model, the equivalent modulus of the matrix minerals was calculated using the Hashin-Shtrikman boundary average model.

[0075] In this step, the expression for the Hashin-Shtrikman boundary average model is:

[0076]

[0077] Where subscript 1 represents one mineral and subscript 2 represents another mineral; K is the bulk modulus of the corresponding mineral and μ is the shear modulus of the corresponding mineral; other parameters are the same as above; when quartz is defined as subscript 1 and the first clay mineral is defined as subscript 2, the calculated K HS± Upper limit of bulk modulus of mixed minerals, μ HS±This represents the upper limit of the shear modulus of the mixed minerals; when the first clay mineral is defined as subscript 1 and quartz as subscript 2, the calculated K is... HS± The lower limit of the bulk modulus of mixed minerals, μ HS± This represents the lower limit of the shear modulus of mixed minerals.

[0078] S4. By utilizing the relationship between effective stress and pore aspect ratio, dry pores with a certain degree of connectivity are added to the matrix minerals to obtain the dry rock skeleton modulus.

[0079] In this step, the relationship between the effective stress and the pore aspect ratio is expressed as follows:

[0080]

[0081] P c =P e +nP p ;

[0082]

[0083] Where α is the pore aspect ratio, α0 and x are given parameters, and P c For confining pressure, P e For effective stress, P p Where is the pore pressure, n is the effective stress coefficient, and K is the pore pressure. dry This represents the bulk modulus of dry rock.

[0084] S5. Using the Wood equation, free water and bound water are mixed, and the bulk modulus of the mixed fluid is calculated.

[0085] In this step, the expression for the Wood equation is:

[0086]

[0087] Among them, f i K represents the volume fraction of each component in the mixed fluid. if K represents the bulk modulus of each component in the fluid mixture. f For the bulk modulus of the mixed fluid, ρ i Let ρ be the density of each component in the fluid mixture, and ρ be the density of the fluid mixture.

[0088] S6. Using the Gassmann equation, the bulk modulus of the mixed fluid is added to the dry rock skeleton modulus to calculate the saturated rock modulus.

[0089] In this step, the expression for the Gassmann equation is:

[0090]

[0091] μ sat =μdry ;

[0092] Among them, K sat μ is the bulk modulus of saturated rock. sat This represents the saturated rock shear modulus.

[0093] S7. Based on the saturated rock modulus, the predicted P-wave velocity and predicted S-wave velocity are calculated.

[0094] In this step, the formula for calculating the predicted P-wave velocity of the saturated rock is:

[0095]

[0096] The formula for calculating the predicted shear wave velocity of the saturated rock is:

[0097]

[0098] Among them, v p For the predicted P-wave velocity of saturated rock, v s The predicted transverse wave velocity for saturated rocks.

[0099] Specifically, this method targets deep sandstone formations with abnormally high pressure, where the overall formation pressure coefficient is relatively high, and the influence of effective stress cannot be ignored in rock physics modeling. Therefore, by comprehensively considering the relationship between effective stress and pore aspect ratio, and taking into account the influence of fluid flow between pores, a sandstone rock physics equivalent model based on the influence of effective stress is established to calculate the corresponding saturated rock elastic parameters. The application effect in the study area is good, effectively solving the problem of large error in velocity prediction of deep sandstone formations in the study area by conventional rock physics models.

[0100] Example 2:

[0101] See Figure 2 This disclosure provides a method for constructing a physical model of sandstone, which is based on the influence of effective stress and includes the following steps:

[0102] (1) Determination of the modulus of the rock matrix minerals: Micropores containing non-flowing fluids are added to clay minerals through the KT model to form "pure shale"; Since the modulus of quartz and clay differs greatly, VRH averaging is no longer applicable, so HS boundary averaging model is used to calculate the equivalent modulus of the matrix minerals.

[0103] The KT model formula is as follows:

[0104]

[0105]

[0106] In the formula, K* KT K is the equivalent medium bulk modulus. m K represents the bulk modulus of the rock matrix. i The bulk modulus of the pore inclusions. μ is the equivalent medium shear modulus. m μ is the shear modulus of the rock matrix. i denoted as shear modulus of pore inclusions; p and q are coefficients related to the type of pore inclusions, which can characterize the influence of different types of inclusions (spheres, needles, coins, etc.) on the equivalent modulus of rocks.

[0107] The formula for the VRH average model is as follows:

[0108]

[0109] In the formula, N represents the type of mineral; f i M represents the volume fraction of the i-th mineral. i M represents the elastic modulus of the i-th mineral; i M represents the elastic modulus at the upper boundary. R M represents the elastic modulus of the lower boundary. VRH This represents the arithmetic mean of the upper and lower boundaries. When the elastic moduli of different minerals differ significantly, the final equivalent elastic modulus parameter of the rock estimated using this model will have a large error.

[0110] The formula for the HS boundary average model is as follows:

[0111]

[0112] In this context, subscript 1 represents one type of mineral, and subscript 2 represents another type of mineral, namely, a mineral with hard components and a mineral with soft components; K and μ represent the bulk modulus and shear modulus of the corresponding components, respectively, and other parameters are the same as above.

[0113] (2) Determination of dry rock skeleton modulus: By introducing the relationship between effective stress and pore aspect ratio (formula (10)), dry pores with certain connectivity are added to the matrix mineral, and the dry rock skeleton modulus is calculated.

[0114] The expression that satisfies the relationship between confining pressure, pore pressure, and effective stress is as follows:

[0115] P c =P e +nP p (8)

[0116] Among them, P c P represents confining pressure. e P represents the effective stress. pLet n represent the pore pressure, and n represent the effective stress coefficient (also known as the Boit coefficient). The formula for calculating the effective stress coefficient is:

[0117]

[0118] Among them, K dry K represents the bulk modulus of dry rock. m Same as above.

[0119] From formulas (8) and (9), we can know that P e K is related to n dry This is related to the pore aspect ratio; the pore aspect ratio is related to P. e They are interconnected, therefore P e There is a coupling relationship between the rock velocity and the effective stress, which can be solved through simultaneous iteration. As the confining pressure increases, the effective stress increases, some soft pores close, the overall pore aspect ratio of the rock increases and the overall porosity decreases, while the velocity increases accordingly. Assuming that the relationship between rock velocity and effective stress is equivalent to the relationship between rock velocity and pore aspect ratio, the following relationship is derived:

[0120]

[0121] Where α represents the aspect ratio of the pores, and α0 and x represent parameters to be given, which can be obtained by fitting experimental data.

[0122] Determining the saturated rock modulus: The bulk modulus of the mixed fluid is obtained by mixing the pore fluid using the Wood equation; then the saturated rock modulus is calculated using the Gassmann equation.

[0123] The Wood equation is as follows:

[0124]

[0125]

[0126] Among them, f i K represents the volume fraction of each component in the mixed fluid. if K represents the bulk modulus of each component in the fluid mixture. f For the bulk modulus of the mixed fluid, ρ i Let ρ be the density of each component in the fluid mixture, and ρ be the density of the fluid mixture.

[0127] The Gassmann equation is as follows:

[0128]

[0129] μ sat =μ dry (14)

[0130] Among them, K sat μ sat These represent the saturated rock bulk modulus and shear modulus after the Gassmann equation is replaced, respectively; the rest are the same as above.

[0131] The corresponding P-wave and S-wave velocities are calculated using the following formulas:

[0132]

[0133] Among them, v p v s These represent the longitudinal wave velocity and transverse wave velocity of saturated rock, respectively, and the rest are the same as above.

[0134] Furthermore, this embodiment conducts an application study of rock physics models based on the influence of effective stress through the production project "Target Processing and Comprehensive Study of Seismic Data in the Western Slope Zone (Southern Region)". The western slope zone is a secondary tectonic unit in the western part of the Xihu Depression in the East China Sea shelf basin. It is adjacent to the Haijiao Uplift to the west and the Santan Deep Depression to the east. It is a favorable zone with the highest degree of oil and gas exploration and development. The western slope zone has a complex structure with well-developed fault blocks, thin reservoir thickness, vertical stacking, and poor lateral continuity. The work area includes the Tuanting, Pinghu, Shaoxing 36-5, Qiuyue and other oil and gas fields and their surrounding areas. It has rich oil and gas-bearing strata, good reservoir conditions, and great potential, which is of great significance for supporting the stable production of the old Xihu area in the East China Sea. Observations revealed that there is abnormally high pressure in the deep sandstone strata below 3500m in the work area, and the overall formation pressure coefficient is high. Conventional rock physics models are difficult to apply, so this method is implemented.

[0135] According to this method, the depth range for constructing the rock physical model is first determined, and then the corresponding rock physical model is established according to the process. The improved rock physical model is applied to well A in the work area to predict velocity, and the calculation results are compared with those calculated by the conventional rock physical model. Figure 3a The predicted shear wave velocity based on a conventional rock physics model is shown. Figure 3b The predicted shear wave velocity based on the rock physics model based on the influence of effective stress is shown, where the vertical axis represents the rock layer depth and the horizontal axis represents the velocity. The solid line represents the measured values ​​from well logging, and the dashed line represents the predicted values. The comparison shows that the predicted shear wave velocity based on the rock physics model based on the influence of effective stress fits the measured values ​​from well logging better, and the prediction accuracy of this method is higher. Figure 4a The diagram shows the error distribution of predicted shear wave velocities based on a conventional rock physics model. Figure 4b The diagram shows the error distribution of predicted shear wave velocity based on the rock physics model with effective stress influence. The prediction error of shear wave based on the conventional rock physics model is about 20%, while the prediction error of shear wave based on the mineral modulus estimation of the incompletely consolidated model is about 10%. The method presented here has higher prediction accuracy. Figure 5a The predicted P-wave velocity is shown based on a conventional rock physics model. Figure 5b The predicted P-wave velocity based on the rock physics model of effective stress influence is shown, where the vertical axis represents the rock layer depth and the horizontal axis represents the velocity. The solid line represents the measured values ​​from well logging, and the dashed line represents the predicted values. The comparison shows that the predicted P-wave velocity based on the conventional rock physics model fits the measured values ​​from well logging poorly, while the predicted P-wave velocity based on the rock physics model of effective stress influence fits the measured values ​​from well logging better. This method has higher prediction accuracy. Figure 6a The diagram shows the error distribution of predicted P-wave velocities based on a conventional rock physics model. Figure 6b The diagram shows the error distribution of predicted P-wave velocity based on the rock physics model with effective stress influence. The comparison shows that the P-wave prediction error based on the conventional rock physics model is about 20%, while the P-wave prediction error based on the rock physics model with effective stress influence is about 10%. The method presented here has higher prediction accuracy.

[0136] Example 3:

[0137] This disclosure also provides an electronic device, which includes:

[0138] At least one processor; and,

[0139] A memory communicatively connected to the at least one processor; wherein,

[0140] The memory stores instructions that can be executed by the at least one processor, which enables the at least one processor to perform the sandstone rock physical model construction method in Embodiment 1 or 2.

[0141] An electronic device according to embodiments of the present disclosure includes a memory and a processor. The memory is used to store non-transitory computer-readable instructions. Specifically, the memory may include one or more computer program products, which 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 random access memory (RAM) and / or cache memory. The non-volatile memory may, for example, include read-only memory (ROM), hard disk, flash memory, etc.

[0142] The processor may be a central processing unit (CPU) or other form of processing unit with 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 this disclosure, the processor is used to execute computer-readable instructions stored in the memory.

[0143] Those skilled in the art will understand that, in order to solve the technical problem of how to achieve a good user experience, this embodiment may also include well-known structures such as communication buses and interfaces, and these well-known structures should also be included within the protection scope of this disclosure.

[0144] For a detailed description of this embodiment, please refer to the corresponding descriptions in the foregoing embodiments, which will not be repeated here.

[0145] Example 4:

[0146] This disclosure provides a non-transitory computer-readable storage medium storing computer instructions for causing a computer to execute the sandstone rock physical model construction method in Embodiment 1 or 2.

[0147] A computer-readable storage medium according to embodiments of the present disclosure stores non-transitory computer-readable instructions. When these non-transitory computer-readable instructions are executed by a processor, all or part of the steps of the methods described in the foregoing embodiments of the present disclosure are performed.

[0148] The aforementioned 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 portable hard drive), media with built-in rewritable non-volatile memory (e.g., memory card), and media with built-in ROM (e.g., ROM cartridge).

[0149] Example 5:

[0150] Referring to the figure, this disclosure provides a sandstone rock physical model construction device, including:

[0151] The sandstone rock physical model setting module is used to set the sandstone rock physical model, including a quartz model and a clay mineral model.

[0152] The pure shale model construction module is used to add micropores containing non-flowing fluids to a clay mineral model using a KT model to obtain a pure shale model.

[0153] The matrix mineral equivalent modulus calculation module is used to calculate the matrix mineral equivalent modulus based on the quartz model and the pure shale model using the Hashin-Shtrikman boundary average model.

[0154] The dry rock skeleton modulus calculation module is used to add dry pores with a certain degree of connectivity to the matrix mineral based on the relationship between effective stress and pore aspect ratio to obtain the dry rock skeleton modulus.

[0155] The mixed fluid bulk modulus calculation module is used to calculate the bulk modulus of the mixed fluid by mixing free water and bound water using the Wood equation.

[0156] The saturated rock modulus calculation module is used to calculate the saturated rock modulus by adding the bulk modulus of the mixed fluid to the dry rock skeleton modulus using the Gassmann equation.

[0157] The predicted velocity calculation module is used to calculate the predicted P-wave velocity and predicted S-wave velocity based on the saturated rock modulus.

[0158] The various embodiments of the present invention have been described above. These descriptions are exemplary and not exhaustive, nor are they limited to the disclosed embodiments. Many modifications and variations will be apparent to those skilled in the art without departing from the scope and spirit of the described embodiments.

Claims

1. A method for constructing a physical model of sandstone, characterized in that, Includes the following steps: The physical model of the sandstone is defined to include a quartz model and a clay mineral model; By adding micropores containing non-flowing fluids to a clay mineral model using the KT model, a pure shale model was obtained. Based on the quartz model and the pure shale model, the equivalent modulus of the matrix minerals was calculated using the Hashin-Shtrikman boundary average model. By utilizing the relationship between effective stress and pore aspect ratio, dry pores with a certain degree of connectivity are added to the matrix minerals to obtain the dry rock skeleton modulus. The bulk modulus of the mixture was calculated by mixing free water and bound water using the Wood equation. The saturated rock modulus was calculated by adding the bulk modulus of the mixed fluid to the dry rock skeleton modulus using the Gassmann equation. Based on the saturated rock modulus, the predicted P-wave velocity and predicted S-wave velocity were calculated.

2. The method for constructing a sandstone rock physical model according to claim 1, characterized in that, The KT model expression is: In the formula, K * KT K is the equivalent medium bulk modulus. m K represents the bulk modulus of the rock matrix. i The bulk modulus of the pore inclusions. μ is the equivalent medium shear modulus. m μ is the shear modulus of the rock matrix. i denoted as the shear modulus of the pore inclusions; p and q are the influence coefficients characterizing different pore inclusions.

3. The method for constructing a physical model of sandstone according to claim 1, characterized in that, The expression for the Hashin-Shtrikman boundary average model is as follows: Where subscript 1 represents one mineral and subscript 2 represents another mineral; K is the bulk modulus of the corresponding mineral and μ is the shear modulus of the corresponding mineral; other parameters are the same as above; when quartz is defined as subscript 1 and the first clay mineral is defined as subscript 2, the calculated K HS± Upper limit of bulk modulus of mixed minerals, μ HS± This represents the upper limit of the shear modulus of the mixed minerals; when the first clay mineral is defined as subscript 1 and quartz as subscript 2, the calculated K is... HS± The lower limit of the bulk modulus of mixed minerals, μ HS± This represents the lower limit of the shear modulus of mixed minerals.

4. The method for constructing a physical model of sandstone according to claim 1, characterized in that, The relationship between the effective stress and the porosity is expressed as follows: P c =P e +nP p ; Where α is the pore aspect ratio, α0 and x are given parameters, and P c For confining pressure, P e For effective stress, P p Where is the pore pressure, n is the effective stress coefficient, and K is the pore pressure. dry This represents the bulk modulus of dry rock.

5. The method for constructing a physical model of sandstone according to claim 1, characterized in that, The expression for the Wood equation is: Among them, f i K represents the volume fraction of each component in the mixed fluid. if K represents the bulk modulus of each component in the fluid mixture. f For the bulk modulus of the mixed fluid, ρ i Let ρ be the density of each component in the fluid mixture, and ρ be the density of the fluid mixture.

6. The method for constructing a physical model of sandstone according to claim 1, characterized in that, The expression for the Gassmann equation is: m sat =μ dry ; Among them, K sat μ is the bulk modulus of saturated rock. sat This represents the saturated rock shear modulus.

7. The method for estimating the mineral modulus of sandstone according to claim 1, characterized in that, The formula for calculating the predicted P-wave velocity of the saturated rock is: The formula for calculating the predicted shear wave velocity of the saturated rock is: Among them, v p For the predicted P-wave velocity of saturated rock, v s The predicted transverse wave velocity for saturated rocks.

8. An electronic device, characterized in that, The electronic device includes: 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 to enable the at least one processor to perform the sandstone rock physical model construction method according to any one of claims 1-7.

9. A non-transitory computer-readable storage medium, characterized in that, The non-transitory computer-readable storage medium stores computer instructions for causing a computer to execute the sandstone rock physical model construction method according to any one of claims 1-7.

10. A device for constructing a physical model of sandstone, characterized in that, include: The sandstone rock physical model setting module is used to set the sandstone rock physical model, including a quartz model and a clay mineral model. The pure shale model construction module is used to add micropores containing non-flowing fluids to a clay mineral model using a KT model to obtain a pure shale model. The matrix mineral equivalent modulus calculation module is used to calculate the matrix mineral equivalent modulus based on the quartz model and the pure shale model using the Hashin-Shtrikman boundary average model. The dry rock skeleton modulus calculation module is used to add dry pores with a certain degree of connectivity to the matrix mineral based on the relationship between effective stress and pore aspect ratio to obtain the dry rock skeleton modulus. The mixed fluid bulk modulus calculation module is used to calculate the bulk modulus of the mixed fluid by mixing free water and bound water using the Wood equation. The saturated rock modulus calculation module is used to calculate the saturated rock modulus by adding the bulk modulus of the mixed fluid to the dry rock skeleton modulus using the Gassmann equation. The predicted velocity calculation module is used to calculate the predicted P-wave velocity and predicted S-wave velocity based on the saturated rock modulus.

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