Rock physical model construction method, device, equipment, medium and product

Abstract

The invention provides a rock physical model construction method, device, equipment, medium and product. According to the technical scheme, the method comprises the steps that an equivalent matrix modulus is calculated through a matrix stiffness index MSI obtained through longitudinal wave velocity inversion; calculating the rock modulus of the dry rock through the equivalent matrix modulus; calculating the equivalent modulus of the mixed fluid; calculating a fluid-saturated rock equivalent modulus through the equivalent matrix modulus, the dry rock modulus and the mixed fluid equivalent modulus, and performing longitudinal wave velocity inversion through the fluid-saturated rock equivalent modulus to obtain the MSI; and constructing a rock physical model through the equivalent matrix modulus, the dry rock modulus, the mixed fluid equivalent modulus and the fluid-saturated rock equivalent modulus. According to the technical scheme, the problem that the adaptability of a loose sandstone rock physical model based on the Hertz-Mindlin theory is narrow can be solved, and by introducing the MSI coefficient, the method can better adapt to unified rock physical simulation of sandstones of different layer sections, different depths and different cementation degrees.

Description

Technical Field

[0001] This invention relates to the field of oil and gas geophysical exploration technology, and in particular to a method, apparatus, equipment, medium and product for constructing a rock physical model. Background Technology

[0002] Hertz-Mindlin theory is widely used in rock physics simulation of loose sandstone. It is particularly important for understanding the variation between reservoir parameters and rock elastic parameters in rock physics model simulations, and provides theoretical support for well logging shear wave velocity estimation and quantitative interpretation of seismic elastic parameters.

[0003] The reliability of rock physics models directly affects the results of shear wave velocity estimation and quantitative seismic interpretation; therefore, the accuracy of rock physics models is particularly critical. Since loose sandstone and consolidated sandstone require different rock physics models, and the Hertz-Mindlin theory's rock physics model for loose sandstone has limited applicability, it cannot meet diverse rock physics modeling needs.

[0004] Therefore, a new method for constructing rock physics models is needed to better adapt to the unified rock physics simulation of sandstones of different layers, depths, and degrees of cementation, and to meet the needs of shallow and deep rock physics modeling. Summary of the Invention

[0005] This invention provides a method, apparatus, equipment, medium, and product for constructing a rock physics model, which can better adapt to the unified rock physics simulation of sandstone with different layers, depths, and degrees of cementation, and meet the needs of shallow and deep rock physics modeling.

[0006] According to one aspect of the present invention, a method for constructing a rock physics model is provided, comprising:

[0007] The equivalent matrix modulus was calculated using the matrix stiffness index (MSI) obtained by longitudinal wave velocity inversion.

[0008] The dry rock modulus is calculated using the equivalent matrix modulus.

[0009] Calculate the equivalent modulus of the mixed fluid;

[0010] The equivalent modulus of fluid-saturated rock is calculated using the equivalent matrix modulus, the dry rock modulus, and the equivalent modulus of the mixed fluid. The longitudinal wave velocity is then inverted using the equivalent modulus of fluid-saturated rock to obtain the MSI.

[0011] A rock physics model is constructed using the equivalent matrix modulus, the dry rock modulus, the mixed fluid equivalent modulus, and the fluid-saturated rock equivalent modulus.

[0012] Optionally, the equivalent matrix modulus includes: bulk modulus, shear modulus, density, and Poisson's ratio; correspondingly, the equivalent matrix modulus is calculated using the matrix stiffness index (MSI) obtained through longitudinal wave velocity inversion, including:

[0013] The bulk modulus, shear modulus, density, and Poisson's ratio are calculated using the following formulas:

[0014] Km=MSI×(Vsh×Ksh+(1-Vsh)×Kqz)+(1-MSI) / (Vsh / Ksh+(1-Vsh) / Kqz);

[0015] Gm=MSI×(Vsh×Gsh+(1-Vsh)×Gqz)+(1-MSI) / (Vsh / Gsh+(1-Vsh) / Gqz);

[0016] Rhom=Vsh×Rhosh+(1-Vsh)×Rhoqz;

[0017] PRm=(3×Km-2×Gm) / (6×Km+2×Gm);

[0018] Wherein, Vsh is the content of clay minerals in the rock, Ksh is the bulk modulus of pure clay minerals, Kqz is the bulk modulus of pure quartz, Gsh is the shear modulus of pure clay minerals, Gqz is the shear modulus of pure quartz, Rhosh is the density of pure clay minerals, Rhoqz is the density of pure quartz, and Km, Gm, Rhom and PRm are the bulk modulus, shear modulus, density and Poisson's ratio of the equivalent matrix, respectively.

[0019] Optionally, calculating the dry rock modulus using the equivalent matrix modulus includes:

[0020] The rock modulus of the dry rock is calculated using the following formula:

[0021] Khm=((C×C×RR×(1-Phic)×(1-Phic)×Gm×Gm×(Peff / 1000)) / (18×9.8696×(1-PRm)×(1-PRm)))^(1 / 3);

[0022] Ghm=(2+3×FC-PRm×(1+3×FC)) / (10-5×PRm)×((3×C×C×RR×(1-Phic)×(1-Phic)×Gm×Gm×(Peff / 1000)) / (2×9.8696×(1-PRm)×(1-PRm)))^(1 / 3);

[0023] Ghm=(2+3×FC-PRm×(1+3×FC)) / (10-5×PRm)×((3×C×C×RR×(1-Phic)×(1-Phic)×Gm×Gm×(Peff / 1000)) / (2×9.8696×(1-PRm)×(1-PRm)))^(1 / 3);

[0024] Kdry=MSI / ((Phi / Phic) / (Khm+4×Gm / 3)+(1-Phi / Phic) / (Km+4×Gm / 3))+(1-MSI) / ((Phi / Phic) / (Khm+4×Ghm / 3)+(1-Phi / Phic) / (Km+4×Ghm / 3))-MSI×4×Gm / 3-(1-MSI)×4×Ghm / 3;

[0025] Wherein, Khm and Ghm are intermediate variables, Kdry is the modulus of the dry rock, C is the coordination number, RR is the grain angle, Peff = Plitho - Pp, Peff is the equivalent stress, Plitho is the overlying formation pressure, Pp is the pore pressure; Phic is the critical porosity, FC is the friction coefficient, and Phi is the effective porosity.

[0026] Optionally, the calculation of the equivalent modulus of the mixed fluid includes:

[0027] The equivalent modulus of the mixed fluid is calculated using the following formula:

[0028] Rhof=Sw×Rhow+(1-Sw)×Rhog;

[0029] Kf = 1 / (Sw / Kw + (1-Sw) / Kg);

[0030] Where Rhof is the equivalent density of the gas-water two-phase mixture, Sw is the water saturation, Rhow is the density of pure water, and Rhog is the density of pure gas; Kf is the equivalent bulk modulus of the gas-water two-phase mixture, Kw is the bulk modulus of pure water, and Kg is the bulk modulus of pure gas.

[0031] Optionally, the step of calculating the equivalent modulus of the fluid-saturated rock using the equivalent matrix modulus, the dry rock modulus, and the mixed fluid equivalent modulus includes:

[0032] The equivalent modulus of the fluid-saturated rock is calculated using the following formula:

[0033] Keff = Kdry + (1 - Kdry / Km) 2 / (Phi / Kf+(1-Phi) / Km-Kdry / Km 2 );

[0034] Wherein, Keff is the equivalent bulk modulus of fluid-saturated rock, Kdry is the modulus of dry rock, Km is the bulk modulus of the equivalent matrix, Phi is the effective porosity, and Kf is the equivalent bulk modulus of the gas-water two-phase mixture.

[0035] Optionally, obtaining the MSI by inverting the P-wave velocity using the equivalent modulus of the fluid-saturated rock includes:

[0036] The P-wave velocity is calculated using the following formula:

[0037] Rho=(1-Phi)×Rhom+Phi×Rhof;

[0038]

[0039] Wherein, Rho is the density of the saturated fluid rock, Phi is the effective porosity, Rhom is the shear modulus of the equivalent matrix, Rhof is the equivalent density of the gas-water two-phase mixture; Vp is the longitudinal wave velocity, Keff is the equivalent bulk modulus of the fluid-saturated rock, and Geff is the equivalent shear modulus of the fluid-saturated rock.

[0040] Determine the initial solution interval [a,b] for MSI, where a is initially 0 and b is initially 1, such that f(a) and f(b) have opposite signs;

[0041] Calculate the midpoint of the interval c = (a + b) / 2 and calculate the value of f(c);

[0042] Determine the sign of f(c). If f(c) = 0, then c is the zero point we are looking for. If f(c) and f(a) have the same sign, then the zero point is in the interval [c, b], and update a = c. If f(c) and f(b) have the same sign, then the zero point is in the interval [a, c], and update b = c.

[0043] Repeat the above calculations until the error between the calculated P-wave velocity Vp and the logging Vp meets the preset accuracy requirements or reaches the maximum number of iterations.

[0044] Optionally, the method further includes:

[0045] The equivalent shear modulus of the fluid-saturated rock is calculated using the following formula:

[0046] Geff=MSI / ((Phi / Phic) / (Ghm+Gm×(9×Km+8×Gm) / (6×Km+12×Gm))+(1-Phi / Phic) / (Gm +Gm×(9×Km+8×Gm) / (6×Km+12×Gm)))+(1-MSI) / ((Phi / Phic) / (Ghm+Ghm×(9×Khm+8×Ghm) ) / (6×Khm+12×Ghm))+(1-Phi / Phic) / (Gm+Ghm×(9×Khm+8×Ghm) / (6×Khm+12×Ghm)))-M SI×Gm×(9×Km+8×Gm) / (6×Km+12×Gm)-(1-MSI)×Ghm×(9×Khm+8×Ghm) / (6×Khm+12×Ghm);

[0047] The transverse wave velocity can be calculated using the following formula:

[0048]

[0049] Wherein, Vs is the transverse wave velocity, Geff is the equivalent shear modulus of the fluid-saturated rock, and Rho is the density of the fluid-saturated rock.

[0050] According to another aspect of the present invention, a rock physics model building apparatus is provided, comprising:

[0051] The equivalent matrix modulus calculation unit is used to calculate the equivalent matrix modulus through the matrix stiffness index (MSI) obtained by longitudinal wave velocity inversion.

[0052] A dry rock modulus calculation unit is used to calculate the dry rock modulus through the equivalent matrix modulus.

[0053] The equivalent modulus calculation unit for mixed fluids is used to calculate the equivalent modulus of mixed fluids.

[0054] The fluid-saturated rock equivalent modulus calculation unit is used to calculate the fluid-saturated rock equivalent modulus through the equivalent matrix modulus, the dry rock modulus, and the mixed fluid equivalent modulus, and to obtain the MSI by performing longitudinal wave velocity inversion through the fluid-saturated rock equivalent modulus;

[0055] The modulus application unit is used to construct a rock physics model using the equivalent matrix modulus, the dry rock modulus, the mixed fluid equivalent modulus, and the fluid-saturated rock equivalent modulus.

[0056] According to another aspect of the present invention, an electronic device is provided, the electronic device comprising:

[0057] At least one processor; and a memory communicatively connected to the at least one processor; wherein the memory stores a computer program executable by the at least one processor, the computer program being executed by the at least one processor to enable the at least one processor to perform the rock physics model construction method according to any embodiment of the present invention.

[0058] According to another aspect of the present invention, a computer-readable storage medium is provided, the computer-readable storage medium storing computer instructions for causing a processor to execute and implement the rock physics model construction method according to any embodiment of the present invention.

[0059] According to another aspect of the present invention, a computer program product is provided, the computer program product comprising a computer program that, when executed by a processor, implements the rock physics model construction method according to any embodiment of the present invention.

[0060] The technical solution of this invention includes: calculating the equivalent matrix modulus using the matrix stiffness index (MSI) obtained through P-wave velocity inversion; calculating the dry rock modulus using the equivalent matrix modulus; calculating the mixed fluid equivalent modulus; calculating the fluid-saturated rock equivalent modulus using the equivalent matrix modulus, the dry rock modulus, and the mixed fluid equivalent modulus; obtaining the MSI through P-wave velocity inversion using the fluid-saturated rock equivalent modulus; and constructing a rock physics model using the equivalent matrix modulus, the dry rock modulus, the mixed fluid equivalent modulus, and the fluid-saturated rock equivalent modulus. This invention addresses the problem of the narrow adaptability of Hertz-Mindlin-based loose sandstone rock physics models by introducing the MSI coefficient, making them better suited for unified rock physics simulations of sandstones with different layers, depths, and cementation degrees.

[0061] It should be understood that the description in this section is not intended to identify key or essential features of the embodiments of the present invention, nor is it intended to limit the scope of the invention. Other features of the invention will become readily apparent from the following description. Attached Figure Description

[0062] To more clearly illustrate the technical solutions in the embodiments of the present invention, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0063] Figure 1 This is a flowchart of a rock physics model construction method provided in Embodiment 1 of the present invention;

[0064] Figure 2 This is a schematic diagram of the framework of a rock physics model construction method applicable to Embodiment 1 of the present invention;

[0065] Figure 3 This is a comparison chart of predicted and measured shear wave velocities using a variable MSI, applicable to Embodiment 1 of the present invention.

[0066] Figure 4 This is a cross-plot of predicted and measured shear wave velocities using a variable MSI, applicable to Embodiment 1 of the present invention.

[0067] Figure 5 This is a cross-plot of predicted and measured shear wave velocities using constant MSI.

[0068] Figure 6 This is a schematic diagram of a rock physics model construction device provided in Embodiment 2 of the present invention;

[0069] Figure 7 This is a schematic diagram of the structure of an electronic device that implements the rock physics model construction method of the present invention. Detailed Implementation

[0070] To enable those skilled in the art to better understand the present invention, the technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort should fall within the scope of protection of the present invention.

[0071] It should be noted that the terms "first," "second," etc., in the specification, claims, and accompanying drawings of this invention are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such data can be interchanged where appropriate so that the embodiments of the invention described herein can be implemented in orders other than those illustrated or described herein. Furthermore, the terms "comprising" and "having," and any variations thereof, are intended to cover a non-exclusive inclusion; for example, a process, method, system, product, or apparatus that comprises a series of steps or units is not necessarily limited to those steps or units explicitly listed, but may include other steps or units not explicitly listed or inherent to such processes, methods, products, or apparatus.

[0072] Example 1

[0073] Figure 1This is a flowchart of a rock physics model construction method provided in Embodiment 1 of the present invention. This embodiment is applicable to the unified rock physics simulation of sandstone with different layers, depths, and cementation degrees. The method can be executed by a rock physics model construction device, which can be implemented in hardware and / or software and can be configured in an electronic device. Figure 1 As shown, the method includes:

[0074] S110. Calculate the equivalent matrix modulus using the matrix stiffness index (MSI) obtained from longitudinal wave velocity inversion.

[0075] The equivalent matrix modulus is a parameter used in rock physics models to describe the properties of the rock matrix. The calculation of the equivalent matrix modulus considers the content and physical properties of clay minerals and quartz in the rock, reflecting the comprehensive mechanical characteristics of the rock matrix. It plays a crucial role in subsequent calculations of the equivalent modulus of dry rock, mixed fluid, and fluid-saturated rock, as well as in the establishment of rock physics models. MSI is the matrix stiffness exponent. By introducing the MSI coefficient and inverting it from the known P-wave velocity, this invention enables the rock physics model to better adapt to unified rock physics simulations of sandstones of different layers, depths, and degrees of cementation.

[0076] In this embodiment of the invention, the equivalent matrix modulus includes: bulk modulus, shear modulus, density, and Poisson's ratio; correspondingly, step S110 specifically includes:

[0077] Calculate the bulk modulus, shear modulus, density, and Poisson's ratio using the following formulas:

[0078] Km=MSI×(Vsh×Ksh+(1-Vsh)×Kqz)+(1-MSI) / (Vsh / Ksh+(1-Vsh) / Kqz);

[0079] Gm=MSI×(Vsh×Gsh+(1-Vsh)×Gqz)+(1-MSI) / (Vsh / Gsh+(1-Vsh) / Gqz);

[0080] Rhom=Vsh×Rhosh+(1-Vsh)×Rhoqz;

[0081] PRm=(3×Km-2×Gm) / (6×Km+2×Gm);

[0082] Wherein, Vsh is the clay mineral content in the rock (value between 0 and 1), Ksh is the bulk modulus of pure clay minerals, Kqz is the bulk modulus of pure quartz, Gsh is the shear modulus of pure clay minerals, Gqz is the shear modulus of pure quartz, Rhosh is the density of pure clay minerals, Rhoqz is the density of pure quartz, and Km, Gm, Rhom, and PRm are the bulk modulus, shear modulus, density, and Poisson's ratio of the equivalent matrix, respectively. MSI is the matrix stiffness index, where MSI = 0 represents loose sandstone, MSI = 0.5 represents moderately cemented sandstone, and MSI = 1 represents cemented sandstone. In actual wells, MSI varies and is subsequently inverted using known P-wave velocities.

[0083] S120. Calculate the dry rock modulus using the equivalent matrix modulus.

[0084] The dry rock modulus is a parameter describing the mechanical properties of dry rocks. The calculation of the dry rock modulus takes into account a variety of factors and can reflect the mechanical properties of dry rocks relatively accurately. It is of great significance for subsequent calculation of the equivalent modulus of fluid-saturated rocks and prediction of shear wave velocity.

[0085] In this embodiment of the invention, step S120 specifically includes:

[0086] The modulus of dry rock is calculated using the following formula:

[0087] Khm=((C×C×RR×(1-Phic)×(1-Phic)×Gm×Gm×(Peff / 1000)) / (18×9.8696×(1-PRm)×(1-PRm)))^(1 / 3);

[0088] Ghm=(2+3×FC-PRm×(1+3×FC)) / (10-5×PRm)×((3×C×C×RR×(1-Phic)×(1-Phic)×Gm×Gm×(Peff / 1000)) / (2×9.8696×(1-PRm)×(1-PRm)))^(1 / 3);

[0089] Kdry=MSI / ((Phi / Phic) / (Khm+4×Gm / 3)+(1-Phi / Phic) / (Km+4×Gm / 3))+(1-MSI) / ((Phi / Phic) / (Khm+4×Ghm / 3)+(1-Phi / Phic) / (Km+4×Ghm / 3))-MSI×4×Gm / 3-(1-MSI)×4×Ghm / 3;

[0090] Among them, Khm and Ghm are intermediate variables, Kdry is the dry rock modulus, C is the coordination number, which takes values between 6 and 15; RR is the particle angle. When it is less than 1, it indicates that the particle edge is not smooth. When it is equal to 1, it indicates that the particle is spherical. When it is greater than 1, it indicates that the particle edge is smooth; Peff = Plitho - Pp, where Peff is the effective stress, Plitho is the overburden pressure, and Pp is the pore pressure; Phic is the critical porosity, which is between 0.36 and 0.4; FC is the friction coefficient. When FC = 0, it indicates that there is no friction between particles. When 0 < FC < 1, it indicates that there is partial friction between particles. When FC = 1, it indicates that the particles are completely cemented; Phi is the effective porosity.

[0091] S130. Calculate the equivalent modulus of the mixed fluid.

[0092] The equivalent modulus of the mixed fluid is a parameter used to describe the properties of the gas - water two - phase mixed fluid. The calculation of the equivalent modulus of the mixed fluid takes into account the proportions of the gas - water two - phases, as well as their respective densities and bulk moduli, and can reflect the comprehensive mechanical properties of the mixed fluid.

[0093] In the embodiment of the present invention, step S130 specifically includes:

[0094] Calculate the equivalent modulus of the mixed fluid through the following formula:

[0095] Rhof = Sw×Rhow+(1 - Sw)×Rhog;

[0096] Kf = 1 / (Sw / Kw+(1 - Sw) / Kg);

[0097] Among them, Rhof is the equivalent density of the gas - water two - phase mixture, Sw is the water saturation, Rhow is the density of pure water, Rhog is the density of pure gas; Kf is the equivalent bulk modulus of the gas - water two - phase mixture, Kw is the bulk modulus of pure water; Kg is the bulk modulus of pure gas.

[0098] S140. Calculate the equivalent modulus of the rock saturated with fluid through the equivalent matrix modulus, the dry rock modulus, and the equivalent modulus of the mixed fluid, and perform P - wave velocity inversion through the equivalent modulus of the rock saturated with fluid to obtain the MSI.

[0099] The equivalent modulus of fluid-saturated rocks is a parameter describing the equivalent mechanical properties of rocks when saturated with fluids (typically a mixture of water and oil or gas). Calculating the equivalent modulus of fluid-saturated rocks provides a better understanding of the mechanical behavior of rocks in actual subsurface environments, which is crucial for the simulation and interpretation of seismic wave propagation and the assessment of oil and gas reservoirs. P-wave velocity inversion is an important step in rock physics models, used to determine the matrix stiffness index (MSI). Obtaining the MSI through P-wave velocity inversion allows for improvements to the Hertz-Mindlin theory, making it better suited for unified rock physics simulations of sandstones with different layers, depths, and degrees of cementation.

[0100] In this embodiment of the invention, the calculation of the equivalent modulus of fluid-saturated rock using the equivalent matrix modulus, the dry rock modulus, and the equivalent modulus of the mixed fluid includes:

[0101] The equivalent modulus of the fluid-saturated rock is calculated using the following formula:

[0102] Keff = Kdry + (1 - Kdry / Km) 2 / (Phi / Kf+(1-Phi) / Km-Kdry / Km 2 );

[0103] Wherein, Keff is the equivalent bulk modulus of fluid-saturated rock, Kdry is the modulus of dry rock, Km is the bulk modulus of the equivalent matrix, Phi is the effective porosity, and Kf is the equivalent bulk modulus of the gas-water two-phase mixture.

[0104] In this embodiment of the invention, the MSI is obtained by inverting the P-wave velocity using the equivalent modulus of the fluid-saturated rock, including:

[0105] The P-wave velocity is calculated using the following formula:

[0106] Rho=(1-Phi)×Rhom+Phi×Rhof;

[0107]

[0108] Wherein, Rho is the density of the saturated fluid rock, Phi is the effective porosity, Rhom is the shear modulus of the equivalent matrix, Rhof is the equivalent density of the gas-water two-phase mixture; Vp is the longitudinal wave velocity, Keff is the equivalent bulk modulus of the fluid-saturated rock, and Geff is the equivalent shear modulus of the fluid-saturated rock.

[0109] Determine the initial solution interval [a,b] for MSI, where a is initially 0 and b is initially 1, such that f(a) and f(b) have opposite signs;

[0110] Calculate the midpoint of the interval c = (a + b) / 2 and calculate the value of f(c);

[0111] Determine the sign of f(c). If f(c) = 0, then c is the zero point we are looking for. If f(c) and f(a) have the same sign, then the zero point is in the interval [c, b], and update a = c. If f(c) and f(b) have the same sign, then the zero point is in the interval [a, c], and update b = c.

[0112] Repeat the above calculations until the error between the calculated P-wave velocity Vp and the logging Vp meets the preset accuracy requirements or reaches the maximum number of iterations.

[0113] This invention uses Vp obtained from well logging to invert MSI. In calculating Vp, there is only one unknown, MSI, i.e., Vp = f(MSI). A bisection method is used to solve for MSI. ① Determine the initial solution interval [a, b] for MSI, where a is initially 0 and b is initially 1. Ensure that f(a) and f(b) have opposite signs, i.e., f(a) × f(b) < 0. Calculate the midpoint c = (a + b) / 2 within the interval and calculate the value of f(c). ② Determine the sign of f(c): If f(c) = 0, then c is the desired zero point. If f(c) and f(a) have the same sign, then the zero point is within the interval [c, b], and update a = c. If f(c) and f(b) have the same sign, then the zero point is within the interval [a, c], and update b = c. Repeat steps ① and ② until the error between the calculated Vp and the Vp from the well logging meets the preset accuracy requirement or reaches the maximum number of iterations.

[0114] In embodiments of the present invention, the method may further include:

[0115] The equivalent shear modulus of the fluid-saturated rock is calculated using the following formula:

[0116] Geff=MSI / ((Phi / Phic) / (Ghm+Gm×(9×Km+8×Gm) / (6×Km+12×Gm))+(1-Phi / Phic) / (Gm +Gm×(9×Km+8×Gm) / (6×Km+12×Gm)))+(1-MSI) / ((Phi / Phic) / (Ghm+Ghm×(9×Khm+8×Ghm) ) / (6×Khm+12×Ghm))+(1-Phi / Phic) / (Gm+Ghm×(9×Khm+8×Ghm) / (6×Khm+12×Ghm)))-M SI×Gm×(9×Km+8×Gm) / (6×Km+12×Gm)-(1-MSI)×Ghm×(9×Khm+8×Ghm) / (6×Khm+12×Ghm);

[0117] Where Geff is the equivalent shear modulus of fluid-saturated rock, Phi is the effective porosity, Phic is the critical porosity, Khm and Ghm are intermediate variables, and Km, Gm, Rhom and PRm are the bulk modulus, shear modulus, density and Poisson's ratio of the equivalent matrix, respectively.

[0118] The transverse wave velocity can be calculated using the following formula:

[0119]

[0120] Wherein, Vs is the transverse wave velocity, Geff is the equivalent shear modulus of the fluid-saturated rock, and Rho is the density of the fluid-saturated rock.

[0121] Shear wave velocity is a physical quantity that describes the speed at which shear waves propagate in a medium during seismic activity. The calculation of shear wave velocity is of great significance for rock physics research and seismic exploration, as it reflects the physical properties and structural characteristics of rocks, helping researchers better understand subsurface geological conditions.

[0122] S150. Construct a rock physics model using the equivalent matrix modulus, the dry rock modulus, the mixed fluid equivalent modulus, and the fluid-saturated rock equivalent modulus.

[0123] Figure 2 This is a schematic diagram of the framework of a rock physics model construction method applicable to Embodiment 1 of the present invention.

[0124] This invention introduces the MSI coefficient and obtains the MSI through inversion of existing P-wave velocities. This facilitates better adaptation to unified petrophysical simulation of sandstones of different layers, depths, and cementation degrees, enabling a single model to meet the needs of both shallow and deep petrophysical modeling. Furthermore, the MSI inversion results are less affected by human factors and have high reliability.

[0125] Actual data from multiple basins, including the Sichuan Basin and West Siberia, show that the solutions in this invention have a wider range of applications and are suitable for various lithologies such as loose sandstone, dense sandstone, and carbonate rocks.

[0126] Figure 3 This is a comparison chart of the predicted shear wave velocity and the measured shear wave velocity using a variable MSI model applicable to Embodiment 1 of the present invention. It can be seen that after the improvement of the present invention, the predicted shear wave velocity using a variable MSI model is more consistent with the measured shear wave velocity in terms of morphology. This also shows that the improved rock physics model can better adapt to the rock physics modeling of tight sandstone.

[0127] Figure 4 This is a cross-plot of predicted and measured shear wave velocities using a variable MSI, applicable to Embodiment 1 of the present invention. For comparison, Figure 5 This is a cross-plot of predicted and measured shear wave velocities using a constant MSI (Mean Separate Indicator) method. Figure 4 , 5 As can be seen, the transverse waves predicted by the variable MSI are better concentrated on the Y=X line than the measured transverse waves. Before the improvement, the transverse waves predicted by the constant MSI differed significantly from the measured transverse waves. This also shows that the rock physics model constructed in this embodiment of the invention is well applicable to dense sandstone.

[0128] Example 2

[0129] Figure 6 This is a schematic diagram of a rock physics model construction device provided in Embodiment 2 of the present invention. Figure 6 As shown, the device includes:

[0130] The equivalent matrix modulus calculation unit 610 is used to calculate the equivalent matrix modulus through the matrix stiffness index (MSI) obtained by longitudinal wave velocity inversion.

[0131] Dry rock modulus calculation unit 620 is used to calculate the dry rock modulus through the equivalent matrix modulus;

[0132] The equivalent modulus calculation unit 630 for mixed fluids is used to calculate the equivalent modulus of mixed fluids.

[0133] The fluid-saturated rock equivalent modulus calculation unit 640 is used to calculate the fluid-saturated rock equivalent modulus through the equivalent matrix modulus, the dry rock modulus, and the mixed fluid equivalent modulus, and to obtain the MSI by performing longitudinal wave velocity inversion through the fluid-saturated rock equivalent modulus;

[0134] Modulus application unit 650 is used to construct a rock physics model using the equivalent matrix modulus, the dry rock modulus, the mixed fluid equivalent modulus, and the fluid-saturated rock equivalent modulus.

[0135] Optional, the equivalent matrix modulus includes: bulk modulus, shear modulus, density, and Poisson's ratio; correspondingly, the equivalent matrix modulus calculation unit 610 is specifically used to perform:

[0136] Calculate the bulk modulus, shear modulus, density, and Poisson's ratio using the following formulas:

[0137] Km=MSI×(Vsh×Ksh+(1-Vsh)×Kqz)+(1-MSI) / (Vsh / Ksh+(1-Vsh) / Kqz);

[0138] Gm=MSI×(Vsh×Gsh+(1-Vsh)×Gqz)+(1-MSI) / (Vsh / Gsh+(1-Vsh) / Gqz);

[0139] Rhom=Vsh×Rhosh+(1-Vsh)×Rhoqz;

[0140] PRm=(3×Km-2×Gm) / (6×Km+2×Gm);

[0141] Wherein, Vsh is the content of clay minerals in the rock, Ksh is the bulk modulus of pure clay minerals, Kqz is the bulk modulus of pure quartz, Gsh is the shear modulus of pure clay minerals, Gqz is the shear modulus of pure quartz, Rhosh is the density of pure clay minerals, Rhoqz is the density of pure quartz, and Km, Gm, Rhom and PRm are the bulk modulus, shear modulus, density and Poisson's ratio of the equivalent matrix, respectively.

[0142] Optional, dry rock modulus calculation unit 620, specifically used for:

[0143] The modulus of dry rock is calculated using the following formula:

[0144] Khm=((C×C×RR×(1-Phic)×(1-Phic)×Gm×Gm×(Peff / 1000)) / (18×9.8696×(1-PRm)×(1-PRm)))^(1 / 3);

[0145] Ghm=(2+3×FC-PRm×(1+3×FC)) / (10-5×PRm)×((3×C×C×RR×(1-Phic)×(1-Phic)×Gm×Gm×(Peff / 1000)) / (2×9.8696×(1-PRm)×(1-PRm)))^(1 / 3);

[0146] Kdry=MSI / ((Phi / Phic) / (Khm+4×Gm / 3)+(1-Phi / Phic) / (Km+4×Gm / 3))+(1-MSI) / ((Phi / Phic) / (Khm+4×Ghm / 3)+(1-Phi / Phic) / (Km+4×Ghm / 3))-MSI×4×Gm / 3-(1-MSI)×4×Ghm / 3;

[0147] Wherein, Khm and Ghm are intermediate variables, Kdry is the modulus of the dry rock, C is the coordination number, RR is the grain angle, Peff = Plitho - Pp, Peff is the equivalent stress, Plitho is the overlying formation pressure, Pp is the pore pressure; Phic is the critical porosity, FC is the friction coefficient, and Phi is the effective porosity.

[0148] Optional, the mixed fluid equivalent modulus calculation unit 630 is specifically used to perform:

[0149] The equivalent modulus of the mixed fluid is calculated using the following formula:

[0150] Rhof=Sw×Rhow+(1-Sw)×Rhog;

[0151] Kf = 1 / (Sw / Kw + (1-Sw) / Kg);

[0152] Where Rhof is the equivalent density of the gas-water two-phase mixture, Sw is the water saturation, Rhow is the density of pure water, and Rhog is the density of pure gas; Kf is the equivalent bulk modulus of the gas-water two-phase mixture, Kw is the bulk modulus of pure water, and Kg is the bulk modulus of pure gas.

[0153] Optional, the fluid-saturated rock equivalent modulus calculation unit 640 is specifically used to perform:

[0154] The equivalent modulus of the fluid-saturated rock is calculated using the following formula:

[0155] Keff = Kdry + (1 - Kdry / Km) 2 / (Phi / Kf+(1-Phi) / Km-Kdry / Km 2 );

[0156] Wherein, Keff is the equivalent bulk modulus of fluid-saturated rock, Kdry is the modulus of dry rock, Km is the bulk modulus of the equivalent matrix, Phi is the effective porosity, and Kf is the equivalent bulk modulus of the gas-water two-phase mixture.

[0157] Optional, the fluid-saturated rock equivalent modulus calculation unit 640 is specifically used to perform:

[0158] The P-wave velocity is calculated using the following formula:

[0159] Rho=(1-Phi)×Rhom+Phi×Rhof;

[0160]

[0161] Wherein, Rho is the density of the saturated fluid rock, Phi is the effective porosity, Rhom is the shear modulus of the equivalent matrix, Rhof is the equivalent density of the gas-water two-phase mixture; Vp is the longitudinal wave velocity, Keff is the equivalent bulk modulus of the fluid-saturated rock, and Geff is the equivalent shear modulus of the fluid-saturated rock.

[0162] Determine the initial solution interval [a,b] for MSI, where a is initially 0 and b is initially 1, such that f(a) and f(b) have opposite signs;

[0163] Calculate the midpoint of the interval c = (a + b) / 2 and calculate the value of f(c);

[0164] Determine the sign of f(c). If f(c) = 0, then c is the zero point we are looking for. If f(c) and f(a) have the same sign, then the zero point is in the interval [c, b], and update a = c. If f(c) and f(b) have the same sign, then the zero point is in the interval [a, c], and update b = c.

[0165] Repeat the above calculations until the error between the calculated P-wave velocity Vp and the logging Vp meets the preset accuracy requirements or reaches the maximum number of iterations.

[0166] Optionally, the device may also include: a transverse wave velocity calculation unit 660;

[0167] The shear wave velocity calculation unit 660 is specifically used to perform:

[0168] The equivalent shear modulus of the fluid-saturated rock is calculated using the following formula:

[0169] Geff=MSI / ((Phi / Phic) / (Ghm+Gm×(9×Km+8×Gm) / (6×Km+12×Gm))+(1-Phi / Phic) / (Gm +Gm×(9×Km+8×Gm) / (6×Km+12×Gm)))+(1-MSI) / ((Phi / Phic) / (Ghm+Ghm×(9×Khm+8×Ghm) ) / (6×Khm+12×Ghm))+(1-Phi / Phic) / (Gm+Ghm×(9×Khm+8×Ghm) / (6×Khm+12×Ghm)))-M SI×Gm×(9×Km+8×Gm) / (6×Km+12×Gm)-(1-MSI)×Ghm×(9×Khm+8×Ghm) / (6×Khm+12×Ghm);

[0170] Wherein, Geff is the equivalent shear modulus of fluid-saturated rock, Phi is the effective porosity, Phic is the critical porosity, Khm and Ghm are the intermediate variables, and Km, Gm, Rhom, and PRm are the bulk modulus, shear modulus, density, and Poisson's ratio of the equivalent matrix, respectively.

[0171] The transverse wave velocity can be calculated using the following formula:

[0172]

[0173] Wherein, Vs is the transverse wave velocity, Geff is the equivalent shear modulus of the fluid-saturated rock, and Rho is the density of the fluid-saturated rock.

[0174] The rock physics model construction device provided in this embodiment of the invention can execute the rock physics model construction method provided in any embodiment of the invention, and has the corresponding functional modules and beneficial effects of the method execution.

[0175] Example 3

[0176] Figure 7 A schematic diagram of an electronic device 10 that can be used to implement embodiments of the present invention is shown. The electronic device is intended to represent various forms of digital computers, such as laptop computers, desktop computers, workstations, personal digital assistants, servers, blade servers, mainframe computers, and other suitable computers. The electronic device can also represent various forms of mobile devices, such as personal digital processors, cellular phones, smartphones, wearable devices (e.g., helmets, glasses, watches, etc.), and other similar computing devices. The components shown herein, their connections and relationships, and their functions are merely illustrative and are not intended to limit the implementation of the invention described and / or claimed herein.

[0177] like Figure 7 As shown, the electronic device 10 includes at least one processor 11 and a memory, such as a read-only memory (ROM) 12 or a random access memory (RAM) 13, communicatively connected to the at least one processor 11. The memory stores computer programs executable by the at least one processor. The processor 11 can perform various appropriate actions and processes based on the computer program stored in the ROM 12 or loaded from storage unit 18 into the RAM 13. The RAM 13 may also store various programs and data required for the operation of the electronic device 10. The processor 11, ROM 12, and RAM 13 are interconnected via a bus 14. An input / output (I / O) interface 15 is also connected to the bus 14.

[0178] Multiple components in electronic device 10 are connected to I / O interface 15, including: input unit 16, such as keyboard, mouse, etc.; output unit 17, such as various types of displays, speakers, etc.; storage unit 18, such as disk, optical disk, etc.; and communication unit 19, such as network card, modem, wireless transceiver, etc. Communication unit 19 allows electronic device 10 to exchange information / data with other devices through computer networks such as the Internet and / or various telecommunications networks.

[0179] Processor 11 can be a variety of general-purpose and / or special-purpose processing components with processing and computing capabilities. Some examples of processor 11 include, but are not limited to, a central processing unit (CPU), a graphics processing unit (GPU), various special-purpose artificial intelligence (AI) computing chips, various processors running machine learning model algorithms, a digital signal processor (DSP), and any suitable processor, controller, microcontroller, etc. Processor 11 performs the various methods and processes described above, such as the rock physics model building method.

[0180] In some embodiments, the rock physics model building method may be implemented as a computer program tangibly contained in a computer-readable storage medium, such as storage unit 18. In some embodiments, part or all of the computer program may be loaded and / or installed on electronic device 10 via ROM 12 and / or communication unit 19. When the computer program is loaded into RAM 13 and executed by processor 11, one or more steps of the rock physics model building method described above may be performed. Alternatively, in other embodiments, processor 11 may be configured to execute the rock physics model building method by any other suitable means (e.g., by means of firmware).

[0181] Various embodiments of the systems and techniques described above herein can be implemented in digital electronic circuit systems, integrated circuit systems, field-programmable gate arrays (FPGAs), application-specific integrated circuits (ASICs), application-specific standard products (ASSPs), systems-on-a-chip (SoCs), payload-programmable logic devices (CPLDs), computer hardware, firmware, software, and / or combinations thereof. These various embodiments may include implementations in one or more computer programs that can be executed and / or interpreted on a programmable system including at least one programmable processor, which may be a dedicated or general-purpose programmable processor, capable of receiving data and instructions from a storage system, at least one input device, and at least one output device, and transmitting data and instructions to the storage system, the at least one input device, and the at least one output device.

[0182] Computer programs used to implement the methods of the present invention may be written in any combination of one or more programming languages. These computer programs may be provided to a processor of a general-purpose computer, a special-purpose computer, or other programmable data processing device, such that when executed by the processor, the computer programs cause the functions / operations specified in the flowcharts and / or block diagrams to be performed. The computer programs may be executed entirely on a machine, partially on a machine, or as a standalone software package, partially on a machine and partially on a remote machine, or entirely on a remote machine or server.

[0183] In the context of this invention, a computer-readable storage medium can be a tangible medium that may contain or store a computer program for use by or in conjunction with an instruction execution system, apparatus, or device. A computer-readable storage medium may include, but is not limited to, electronic, magnetic, optical, electromagnetic, infrared, or semiconductor systems, apparatus, or devices, or any suitable combination thereof. Alternatively, a computer-readable storage medium may be a machine-readable signal medium. More specific examples of machine-readable storage media include electrical connections based on one or more wires, portable computer disks, hard disks, random access memory (RAM), read-only memory (ROM), erasable programmable read-only memory (EPROM or flash memory), optical fibers, portable compact disk read-only memory (CD-ROM), optical storage devices, magnetic storage devices, or any suitable combination thereof.

[0184] To provide interaction with a user, the systems and techniques described herein can be implemented on an electronic device having: a display device (e.g., a CRT (cathode ray tube) or LCD (liquid crystal display) monitor) for displaying information to the user; and a keyboard and pointing device (e.g., a mouse or trackball) through which the user provides input to the electronic device. Other types of devices can also be used to provide interaction with the user; for example, feedback provided to the user can be any form of sensory feedback (e.g., visual feedback, auditory feedback, or tactile feedback); and input from the user can be received in any form (including sound input, voice input, or tactile input).

[0185] The systems and technologies described herein can be implemented in computing systems that include backend components (e.g., as data servers), or computing systems that include middleware components (e.g., application servers), or computing systems that include frontend components (e.g., user computers with graphical user interfaces or web browsers through which users can interact with implementations of the systems and technologies described herein), or any combination of such backend, middleware, or frontend components. The components of the system can be interconnected via digital data communication of any form or medium (e.g., communication networks). Examples of communication networks include local area networks (LANs), wide area networks (WANs), blockchain networks, and the Internet.

[0186] A computing system can include clients and servers. Clients and servers are generally located far apart and typically interact through communication networks. The client-server relationship is created by computer programs running on the respective computers and having a client-server relationship with each other. The server can be a cloud server, also known as a cloud computing server or cloud host, which is a hosting product within the cloud computing service system to address the shortcomings of traditional physical hosts and VPS services, such as high management difficulty and weak business scalability.

[0187] It should be understood that the various forms of processes shown above can be used, with steps reordered, added, or deleted. For example, the steps described in this invention can be executed in parallel, sequentially, or in different orders, as long as the desired result of the technical solution of this invention can be achieved, and this is not limited herein.

[0188] The specific embodiments described above do not constitute a limitation on the scope of protection of this invention. Those skilled in the art should understand that various modifications, combinations, sub-combinations, and substitutions can be made according to design requirements and other factors. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of this invention should be included within the scope of protection of this invention.

Claims

1. A method for constructing a rock physical model, characterized in that, include: The equivalent matrix modulus was calculated using the matrix stiffness index (MSI) obtained by longitudinal wave velocity inversion. The dry rock modulus is calculated using the equivalent matrix modulus. Calculate the equivalent modulus of the mixed fluid; The equivalent modulus of fluid-saturated rock is calculated using the equivalent matrix modulus, the dry rock modulus, and the equivalent modulus of the mixed fluid. The longitudinal wave velocity is then inverted using the equivalent modulus of fluid-saturated rock to obtain the MSI. A rock physics model is constructed using the equivalent matrix modulus, the dry rock modulus, the mixed fluid equivalent modulus, and the fluid-saturated rock equivalent modulus.

2. The method according to claim 1, characterized in that, The equivalent matrix modulus includes: bulk modulus, shear modulus, density, and Poisson's ratio; correspondingly, the equivalent matrix modulus is calculated using the matrix stiffness index (MSI) obtained through longitudinal wave velocity inversion, including: The bulk modulus, shear modulus, density, and Poisson's ratio are calculated using the following formulas: Km=MSI×(Vsh×Ksh+(1-Vsh)×Kqz)+(1-MSI) / (Vsh / Ksh+(1-Vsh) / Kqz); Gm=MSI×(Vsh×Gsh+(1-Vsh)×Gqz)+(1-MSI) / (Vsh / Gsh+(1-Vsh) / Gqz); Rhom=Vsh×Rhosh+(1-Vsh)×Rhoqz; PRm=(3×Km-2×Gm) / (6×Km+2×Gm); Wherein, Vsh is the content of clay minerals in the rock, Ksh is the bulk modulus of pure clay minerals, Kqz is the bulk modulus of pure quartz, Gsh is the shear modulus of pure clay minerals, Gqz is the shear modulus of pure quartz, Rhosh is the density of pure clay minerals, Rhoqz is the density of pure quartz, and Km, Gm, Rhom and PRm are the bulk modulus, shear modulus, density and Poisson's ratio of the equivalent matrix, respectively.

3. The method according to claim 2, characterized in that, The calculation of the dry rock modulus using the equivalent matrix modulus includes: The rock modulus of the dry rock is calculated using the following formula: Khm=((C×C×RR×(1-Phic)×(1-Phic)×Gm×Gm×(Peff / 1000)) / (18×9.8696×(1-PRm)×(1-PRm)))^(1 / 3); Ghm=(2+3×FC-PRm×(1+3×FC)) / (10-5×PRm)×((3×C×C×RR× (1-Phic)×(1-Phic)×Gm×Gm×(Peff / 1000)) / (2×9.8696×(1-PRm)× (1-PRm)))^(1 / 3); Kdry=MSI / ((Phi / Phic) / (Khm+4×Gm / 3)+(1-Phi / Phic) / (Km+4× Gm / 3))+(1-MSI) / ((Phi / Phic) / (Khm+4×Ghm / 3)+(1-Phi / Phic) / (Km+4× Ghm / 3))-MSI×4×Gm / 3-(1-MSI)×4×Ghm / 3; Wherein, Khm and Ghm are intermediate variables, Kdry is the modulus of the dry rock, C is the coordination number, RR is the grain angle, Peff = Plitho - Pp, Peff is the equivalent stress, Plitho is the overlying formation pressure, Pp is the pore pressure; Phic is the critical porosity, FC is the friction coefficient, and Phi is the effective porosity.

4. The method according to claim 1, characterized in that, The calculation of the equivalent modulus of the mixed fluid includes: The equivalent modulus of the mixed fluid is calculated using the following formula: Rhof=Sw×Rhow+(1-Sw)×Rhog; Kf = 1 / (Sw / Kw + (1-Sw) / Kg); Where Rhof is the equivalent density of the gas-water two-phase mixture, Sw is the water saturation, Rhow is the density of pure water, and Rhog is the density of pure gas; Kf is the equivalent bulk modulus of the gas-water two-phase mixture, Kw is the bulk modulus of pure water, and Kg is the bulk modulus of pure gas.

5. The method according to claim 4, characterized in that, The calculation of the equivalent modulus of fluid-saturated rock using the equivalent matrix modulus, the dry rock modulus, and the equivalent modulus of the mixed fluid includes: The equivalent modulus of the fluid-saturated rock is calculated using the following formula: Keff1Kdry+(1-Kdry / Km) 2 / (Phi / Kf+(1-Phi) / Km-Kdry / Km 2 )4 Wherein, Keff is the equivalent bulk modulus of fluid-saturated rock, Kdry is the modulus of dry rock, Km is the bulk modulus of the equivalent matrix, Phi is the effective porosity, and Kf is the equivalent bulk modulus of the gas-water two-phase mixture.

6. The method according to claim 5, characterized in that, The step of obtaining the MSI by inverting the P-wave velocity using the equivalent modulus of the fluid-saturated rock includes: The P-wave velocity is calculated using the following formula: Rho=(1-Phi)×Rhom+Phi×Rhof; Wherein, Rho is the density of the saturated fluid rock, Phi is the effective porosity, Rhom is the shear modulus of the equivalent matrix, Rhof is the equivalent density of the gas-water two-phase mixture; Vp is the longitudinal wave velocity, Keff is the equivalent bulk modulus of the fluid-saturated rock, and Geff is the equivalent shear modulus of the fluid-saturated rock. Determine the initial solution interval [a,b] for MSI, where a is initially 0 and b is initially 1, such that f(a) and f(b) have opposite signs; Calculate the midpoint of the interval c = (a + b) / 2 and calculate the value of f(c); Determine the sign of f(c). If f(c) = 0, then c is the zero point we are looking for. If f(c) and f(a) have the same sign, then the zero point is in the interval [c, b], and update a = c. If f(c) and f(b) have the same sign, then the zero point is in the interval [a, c], and update b = c. Repeat the above calculations until the error between the calculated P-wave velocity Vp and the logging Vp meets the preset accuracy requirements or reaches the maximum number of iterations.

7. The method according to claim 6, characterized in that, Further includes: The equivalent shear modulus of the fluid-saturated rock is calculated using the following formula: Geff=MSI / ((Phi / Phic) / (Ghm+Gm×(9×Km+8×Gm) / (6×Km+12×Gm))+(1-Phi / Phic) / (Gm+Gm×(9×Km +8×Gm) / (6×Km+12×Gm)))+(1-MSI) / ((Phi / Phic) / (Ghm+Ghm×(9×Khm+8×Ghm) / (6×Khm+12×Ghm))+ (1-Phi / Phic) / (Gm+Ghm×(9×Khm+8×Ghm) / (6×Khm+12×Ghm)))-MSI×Gm×(9×Km+8×Gm) / (6×Km+12×Gm)-(1-MSI)×Ghm×(9×Khm+8×Ghm) / (6×Khm+12×Ghm); Wherein, Geff is the equivalent shear modulus of fluid-saturated rock, Phi is the effective porosity, Phic is the critical porosity, Khm and Ghm are the intermediate variables, and Km, Gm, Rhom, and PRm are the bulk modulus, shear modulus, density, and Poisson's ratio of the equivalent matrix, respectively. The transverse wave velocity can be calculated using the following formula: Wherein, Vs is the transverse wave velocity, Geff is the equivalent shear modulus of the fluid-saturated rock, and Rho is the density of the fluid-saturated rock.

8. A rock physics model construction device, characterized in that, include: The equivalent matrix modulus calculation unit is used to calculate the equivalent matrix modulus through the matrix stiffness index (MSI) obtained by longitudinal wave velocity inversion. A dry rock modulus calculation unit is used to calculate the dry rock modulus through the equivalent matrix modulus. The equivalent modulus calculation unit for mixed fluids is used to calculate the equivalent modulus of mixed fluids. The fluid-saturated rock equivalent modulus calculation unit is used to calculate the fluid-saturated rock equivalent modulus through the equivalent matrix modulus, the dry rock modulus, and the mixed fluid equivalent modulus, and to obtain the MSI by performing longitudinal wave velocity inversion through the fluid-saturated rock equivalent modulus; The modulus application unit is used to construct a rock physics model using the equivalent matrix modulus, the dry rock modulus, the mixed fluid equivalent modulus, and the fluid-saturated rock equivalent modulus.

9. 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 a computer program executable by the at least one processor, the computer program being executed by the at least one processor to enable the at least one processor to perform the rock physics model construction method according to any one of claims 1-7.

10. A computer-readable storage medium, characterized in that, The computer-readable storage medium stores computer instructions that cause a processor to execute the rock physics model construction method according to any one of claims 1-7.

11. A computer program product, characterized in that, The computer program product includes a computer program that, when executed by a processor, implements the rock physics model construction method according to any one of claims 1-7.

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