Rock transverse and longitudinal wave velocity prediction method and device, electronic equipment and program product
By obtaining the physical parameters of marine-continental transitional shale and calculating rock velocities using differential equivalent media and self-compatible equivalent models, the exploration and development challenges in existing technologies have been solved, enabling efficient prediction and modification of shale gas reservoirs.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- CHINA PETROLEUM & CHEMICAL CORP
- Filing Date
- 2024-12-27
- Publication Date
- 2026-06-30
Smart Images
Figure CN122307693A_ABST
Abstract
Description
Technical Field
[0001] This invention relates to a method, apparatus, electronic equipment, and program product for predicting transverse and longitudinal wave velocities in marine-continental transitional shale rocks. Background Technology
[0002] Marine Permian shale belongs to the marine-continental transitional shale gas reservoir, which is rich in resources and has good development prospects. Establishing a seismic petrophysical model for marine-continental transitional shale can effectively support exploration and development work in shale reservoirs, including shear wave prediction, sweet spot prediction, and fluid identification. Due to the low porosity and low permeability characteristics of reservoir "sweet spots," vertical well production is low. Furthermore, because geological "sweet spots" are thin vertically and change rapidly laterally, and the distribution characteristics of engineering "sweet spots" are unclear, the lack of effective petrophysical models leads to challenges for horizontal wells, such as difficulty in target entry, low encounter rate of high-quality sweet spots, and significant differences in fracturing effects. Therefore, it is urgent to develop an effective seismic prediction method to comprehensively describe the structure and reservoir characteristics of shale gas "sweet spots," providing support for the efficient development of horizontal wells. Summary of the Invention
[0003] This invention provides a method and related products for predicting the transverse and longitudinal wave velocities of marine-continental transitional shale rocks, in order to accurately predict the transverse and longitudinal wave velocities of marine-continental transitional shale rocks.
[0004] The technical solution of the present invention is as follows: a device for predicting transverse and longitudinal wave velocities of marine-continental transitional shale rocks, comprising: obtaining the porosity, density, and volume contents of quartz, clay, carbonate rocks, and pyrite in marine-continental transitional shale rocks;
[0005] The equivalent matrix elastic modulus is determined based on porosity and the volume contents of quartz, clay, carbonate rock, and pyrite.
[0006] The bulk modulus and shear modulus of the organic matter skeleton are determined based on the bulk modulus and shear modulus of the main phase material, as well as the volume content, bulk modulus, and shear modulus of the inclusions.
[0007] The bulk modulus and shear modulus of shale matrix minerals are obtained based on the equivalent matrix elastic modulus, the bulk modulus of the organic matter skeleton, and the shear modulus.
[0008] The bulk modulus and shear modulus of saturated fluid shale are determined by mixing fluid, shale matrix minerals, and hard pores and fractures.
[0009] In some implementations, the equivalent matrix elastic modulus is determined according to the following formula:
[0010]
[0011] Among them, MH The equivalent matrix elastic modulus, i is the phase or pore space number of minerals such as quartz, clay, carbonate, and pyrite, N=5, f i M represents the volume content of the i-th medium. i This represents the elastic modulus of the i-th medium.
[0012] In some embodiments, the bulk modulus and shear modulus of the organic skeleton are determined by integral of the following formula:
[0013]
[0014] The initial condition is K * (0) = K1 and μ * (0) = μ1, where K1 and μ1 are the bulk modulus and shear modulus of the main phase material, respectively; y, K2, and μ2 are the volume content, bulk modulus, and shear modulus of the included material, respectively; K * and u * In order, they are the volume differential equivalent modulus and the shear differential equivalent modulus, P( *2 )(y) and Q( *2 (y) is the geometric factor of the inclusion.
[0015] In some implementations, the bulk modulus and shear modulus of saturated fluid shale are determined according to the following formulas:
[0016]
[0017]
[0018] in,
[0019]
[0020] Where P1 and Q1 correspond to the volume factors of spherical pores, while P2 and Q2 are approximately corresponding to the volume factors of coin-shaped fissures. Porosity φ is divided into hard porosity φ s and soft porosity φ c Porosity = hard pores + soft pores; the bulk modulus and shear modulus of shale matrix minerals are K0 and K1, respectively. s and μ s The bulk modulus of the fluid is K. f The aspect ratio of the fracture is α, and the volume ratio of the fracture is... It is the bulk modulus of saturated fluid shale. Ks is the shear modulus in saturated fluid shale state, and Ks is the background matrix bulk modulus. β m ζ and ζ are intermediate variables connecting the equations.
[0021] In some implementations, the longitudinal wave V of saturated fluid rock p and transverse wave velocity V s Determine according to the following formula:
[0022]
[0023]
[0024] Where ρ is the bulk density of rock under saturated fluid conditions, K is the bulk modulus of shale under saturated fluid conditions, and μ is the shear modulus of shale under saturated fluid conditions.
[0025] In some embodiments, the parameters in the method for predicting the transverse and longitudinal wave velocities of marine-continental transitional shale rocks are modified.
[0026] The technical solution of the present invention is as follows: A device for predicting the transverse and longitudinal wave velocities of marine-continental transitional shale rocks, comprising:
[0027] The acquisition module is used to obtain the porosity, density, and volume contents of quartz, clay, carbonate rocks, and pyrite in marine-continental transitional shale rocks.
[0028] The first processing module is used to determine the equivalent matrix elastic modulus based on porosity and the volume contents of quartz, clay, carbonate rock and pyrite.
[0029] The second processing module is used to determine the bulk modulus and shear modulus of the organic matter skeleton based on the bulk modulus and shear modulus of the main phase material and the volume content, bulk modulus and shear modulus of the inclusions.
[0030] The third processing module is used to obtain the bulk modulus and shear modulus of shale matrix minerals based on the equivalent matrix elastic modulus, the bulk modulus and shear modulus of the organic matter skeleton.
[0031] The fourth processing module is used to determine the bulk modulus and shear modulus of saturated fluid shale by mixing the fluid, shale matrix minerals, and hard pores and fractures.
[0032] In some implementations, the following are included:
[0033] The correction module is used to correct the parameters of the fourth processing module.
[0034] The technical solution of the present invention is as follows: an electronic device, comprising: a memory and a processor, wherein a program is stored in the memory, and the processor runs the program to execute the above-mentioned method for predicting transverse and longitudinal wave velocities of marine-continental transitional shale rocks.
[0035] The technical solution of the present invention is as follows: a program product that executes the above-mentioned method for predicting transverse and longitudinal wave velocities of marine-continental transitional shale rocks when running on a processor.
[0036] Based on easily measurable physical parameters, the transverse and longitudinal wave velocities of marine-continental transitional shale rocks can be accurately predicted. Attached Figure Description
[0037] Figure 1 This is a schematic flowchart of the method for predicting transverse and longitudinal wave velocities of marine-continental transitional shale rocks according to the present invention.
[0038] Figure 2 This is a structural block diagram of the device for predicting transverse and longitudinal wave velocities of marine-continental transitional shale rocks according to the present invention.
[0039] Figure 3 This is a structural block diagram of the electronic device of the present invention.
[0040] Figure 4 This is an information flow diagram of the method for predicting transverse and longitudinal wave velocities of marine-continental transitional shale rocks according to the present invention.
[0041] Figure 5 It is a cross-plot of organic matter content and porosity.
[0042] Figure 6a and Figure 6b This is a comparison of experimental data with a 2D rock physical template.
[0043] Figure 7 It is the result of comparing well logging data with 3D rock physics templates.
[0044] Figure 8 This is a comparison of the logging data from well A with the velocity predicted by the rock physics model.
[0045] Figure 9 This is a comparison of the logging data of well B with the velocity predicted by the rock physics model. Detailed Implementation
[0046] The present invention will be further described below with reference to specific embodiments, but the scope of protection of the present invention is not limited thereto.
[0047] refer to Figure 1 The present invention provides a method for predicting the transverse and longitudinal wave velocities of marine-continental transitional shale rocks, comprising the following steps.
[0048] Step 101: Obtain the porosity, density, and volume contents of quartz, clay, carbonate, and pyrite in the marine-continental transitional shale rocks.
[0049] The above parameters can be obtained by core experiments and used as input information for rock physics models.
[0050] Step 102: Determine the equivalent matrix elastic modulus based on porosity and the volume contents of quartz, clay, carbonate rock, and pyrite.
[0051] The specific calculation formula is as follows:
[0052] Among them, M H The equivalent matrix elastic modulus, i is the phase or pore space number of minerals such as quartz, clay, carbonate, and pyrite, N=5, f i M represents the volume content of the i-th medium. i This represents the elastic modulus of the i-th medium.
[0053] Step 103: Determine the bulk modulus and shear modulus of the organic matter skeleton based on the bulk modulus and shear modulus of the main phase material and the volume content, bulk modulus and shear modulus of the inclusions.
[0054] The main phase material and background matrix, specifically referring to organic matter. Inclusions, referring to pores.
[0055] Based on the relationship between microstructure, mineral composition, and porosity, a good positive correlation was found between TOC content and porosity in marine shale. It was concluded that the porosity of transitional marine-continental shale is mainly composed of organic matter pores, with the remainder being inorganic pores and a small amount of microfractures. Using the differential equivalent medium theory (DEM), pores with a fixed aspect ratio were added to the organic matter to form an organic matter framework, and its bulk modulus and shear modulus were calculated.
[0056]
[0057] The initial condition is K * (0) = K1 and μ * (0) = μ1, where K1 and μ1 are the bulk modulus and shear modulus of the main phase material, respectively; y, K2, and μ2 are the volume content, bulk modulus, and shear modulus of the included material, respectively; K * and u * In order, they are the volume differential equivalent modulus and the shear differential equivalent modulus, P( *2 )(y) and Q( *2 (y) is the geometric factor of the contained object. A detailed explanation of geometric factors follows.
[0058] Step 104: Obtain the bulk modulus and shear modulus of shale matrix minerals based on the equivalent matrix elastic modulus, the bulk modulus of the organic skeleton, and the shear modulus.
[0059]
[0060] Where, χ i It is the volume content of the i-th medium, n=2, specifically referring to the volume content of the equivalent matrix and organic skeleton, K i and μ i The bulk modulus and shear modulus of the i-th medium are, in order, P. *i and Q *i K represents the geometric factor of the i-th medium. * SC and μ * SC These are the bulk modulus and shear modulus of the shale matrix minerals to be solved, respectively.
[0061] For example, the geometric factor P of the inclusions of an ellipsoid * and Q * for:
[0062]
[0063] In the formula, T ijkl Let T be the elastic tensor of the ellipsoidal inclusion, relating the uniform far-field strain field to the strain within the ellipsoidal inclusion. Specifically, T iijj and T ijij The tensors representing the strain within the ellipsoidal embedding and its relationship to the uniform far-field strain field are respectively denoted as .
[0064] Step 105: Determine the bulk modulus and shear modulus of the saturated fluid shale state by mixing the fluid, shale matrix minerals, and hard pores and fractures. Assuming the porous rock contains spherical pores and fractures, the bulk modulus and shear modulus of the saturated fluid shale state are:
[0065]
[0066] in,
[0067]
[0068] P1 and Q1 correspond to the volume factors of the spherical pore, while P2 and Q2 are approximately the volume factors of the coin-shaped crack.
[0069]
[0070] Where T iijj and T ijij The tensor representing the strain within the ellipsoidal embedding is related to the uniform far-field strain field.
[0071] Porosity φ is divided into hard porosity φ s (Hard pores) and soft porosity φ c(Soft pores). Porosity = Hard pores + Soft pores. The bulk modulus and shear modulus of the shale matrix minerals calculated in step 104 are K, respectively. s and μ s The pore space can be either dry or filled with fluid (in both cases, K) f (The values are different), the fluid bulk modulus is K f The aspect ratio of the fracture is α, and the volume ratio of the fracture is... This parameter is related to the properties of soft and hard pores.
[0072] It is the bulk modulus of saturated fluid shale. Ks is the shear modulus in saturated fluid shale state, and Ks is the background matrix bulk modulus. β m ζ and ζ are intermediate variables connecting the equations.
[0073] Step 106: Determine the longitudinal wave V of saturated fluid rock based on its bulk modulus and shear modulus under saturated fluid shale conditions. p and transverse wave velocity V s .
[0074]
[0075] Where ρ is the bulk density of rock under saturated fluid conditions, and K is the bulk modulus of saturated fluid shale as mentioned earlier. μ refers to the shear modulus in the saturated fluid shale state mentioned earlier.
[0076] Step 107: Measure the longitudinal wave V of the saturated fluid rock obtained in Step 106. p and transverse wave velocity V s By comparing the measured P-wave velocity and measured S-wave velocity, step 106 is corrected to obtain the petrological model of marine-continental transitional shale.
[0077] The petrological model of marine-continental transitional shale is run through steps 101 to 106, where the parameters in step 106 are modified.
[0078] For example, perform a linear transformation on the calculation result obtained in step 106.
[0079] Step 108: Compare the P-wave velocity and S-wave velocity predicted by the marine-continental transitional shale petrophysical model with the well logging data to verify the applicability of the marine-continental transitional shale petrophysical model.
[0080] The information flow graph for this method can be found in the following reference. Figure 4 .
[0081] refer to Figure 2Based on the same inventive concept, embodiments of the present invention also provide a device for predicting the transverse and longitudinal wave velocities of marine-continental transitional shale rocks, comprising:
[0082] Module 1 is used to obtain the porosity, density, quartz volume content, clay volume content, carbonate rock volume content, and pyrite volume content of marine-continental transitional shale rocks.
[0083] The first processing module 2 is used to determine the equivalent matrix elastic modulus based on porosity and the volume contents of quartz, clay, carbonate rock and pyrite.
[0084] The second processing module 3 is used to determine the bulk modulus and shear modulus of the organic matter skeleton based on the bulk modulus and shear modulus of the main phase material and the volume content, bulk modulus and shear modulus of the inclusions.
[0085] The third processing module 4 is used to obtain the bulk modulus and shear modulus of shale matrix minerals based on the equivalent matrix elastic modulus, the bulk modulus and shear modulus of the organic matter skeleton.
[0086] The fourth processing module 5 is used to determine the bulk modulus and shear modulus of saturated fluid shale by mixing the fluid, shale matrix minerals, and hard pores and fractures.
[0087] In some embodiments, a correction module is further included for correcting the parameters of the fourth processing module.
[0088] Each of the above modules can be implemented in software, hardware, or a combination of both.
[0089] refer to Figure 3 Based on the same inventive concept, embodiments of the present invention also provide an electronic device, including: a memory and a processor, wherein a program is stored in the memory, and the processor runs the program to execute the above-described method for predicting transverse and longitudinal wave velocities of marine-continental transitional shale rocks.
[0090] The memory can be any known type of memory, such as a hard drive, flash memory, or optical disc. The processor can be any known type of processor, such as a central processing unit (CPU) or a graphics processing unit (GPU).
[0091] Based on the same inventive concept, embodiments of the present invention also provide a program product that executes the above-described method for predicting transverse and longitudinal wave velocities of marine-continental transitional shale rocks when running on a processor.
[0092] The following combination Figures 5 to 9 Here is a test case.
[0093] 1. Based on core experiments, obtain the mineral composition (quartz, clay, carbonate rock, pyrite) and content of the sample, as well as the physical property parameters (porosity, density), and obtain the input parameters for the rock physics model;
[0094] 2. First, based on the Voigt-Reuss-Hill (VRH) theory, calculate the equivalent matrix elastic modulus of the mixed minerals of quartz, clay, carbonate rock, and pyrite.
[0095] 3. Based on the relationship between microstructure and mineral composition and porosity, it is found that the TOC content of marine shale has a good positive correlation with porosity. It is believed that the porosity of marine-continental transitional shale is mainly organic matter pores, with the remainder being inorganic pores and a small amount of microfractures. Using the differential equivalent medium theory (DEM), pores with a fixed aspect ratio are added to the organic matter to form an organic matter skeleton, and its bulk modulus and shear modulus are calculated.
[0096] 4. Then, the matrix minerals and organic skeleton from step 2 are mixed together using the self-compatible equivalent model SCA to obtain shale matrix minerals. The SCA expressions used are the aforementioned formulas (2) and (3).
[0097] The SCA model is characterized by a continuous distribution of multiple mineral components and pores, making it suitable for situations where multiple matrices serve as the background matrix of rocks.
[0098] 5. Finally, the equivalent embedded stress averaging (EIAS) theoretical model is used to mix the fluid, shale matrix, hard pores, and fractures to obtain the bulk modulus and shear modulus of the saturated fluid shale state. The expressions of the equivalent embedded stress averaging (EIAS) theoretical model used are the aforementioned formulas (7) and (8).
[0099] 6. Using the aforementioned formulas (14) and (15), combined with the rock bulk density ρ, the longitudinal wave V of the saturated rock is calculated. p and transverse wave velocity V s .
[0100] 7. Construct a rock physics template driven by a rock physics model, project experimental data and well logging data into the rock physics template, and then calibrate the rock physics template. The operation of the rock physics template is performed in the order of steps 1 to 6.
[0101] 8. Compare the predicted velocities of the constructed marine shale rock physics model with well logging data to verify the applicability of the rock physics model.
[0102] Figure 5 The cross-plot of organic matter content and porosity shows a good positive correlation between the two, thus concluding that the main pores in the target area are organic matter pores.
[0103] Figure 6 shows the comparison results between experimental data and 2D rock physical templates. Figure 6a The color scale represents porosity. Figure 6b The color standard is felsic, which shows that the experimental data are in good agreement with the rock physical template.
[0104] Figure 7 The results show that the well logging data and the 3D rock physical template are well consistent.
[0105] Figure 8 and Figure 9 The results show a good agreement between the logging data of wells A and B and the velocities predicted by the rock physics model, verifying that the shale rock physics model has a certain applicability in the target area.
[0106] The various embodiments in this invention are described in a progressive manner. For the same or similar parts between the various embodiments, please refer to each other. Each embodiment focuses on describing the differences from other embodiments.
[0107] The scope of protection of this invention is not limited to the embodiments described above. Obviously, those skilled in the art can make various modifications and variations to this invention without departing from its scope and spirit. If these modifications and variations fall within the scope of the claims of this invention and their equivalents, then the intent of this invention also includes these modifications and variations.
Claims
1. A method for predicting the transverse and longitudinal wave velocities of marine-continental transitional shale rocks, characterized in that, include: The porosity, density, and volume contents of quartz, clay, carbonate rocks, and pyrite in the transitional marine-continental shale rocks were obtained. The equivalent matrix elastic modulus is determined based on porosity and the volume contents of quartz, clay, carbonate rock, and pyrite. The bulk modulus and shear modulus of the organic matter skeleton are determined based on the bulk modulus and shear modulus of the main phase material, as well as the volume content, bulk modulus, and shear modulus of the inclusions. The bulk modulus and shear modulus of shale matrix minerals are obtained based on the equivalent matrix elastic modulus, the bulk modulus of the organic matter skeleton, and the shear modulus. The bulk modulus and shear modulus of saturated fluid shale are determined by mixing fluid, shale matrix minerals, and hard pores and fractures.
2. The method according to claim 1, characterized in that, The equivalent matrix elastic modulus is determined according to the following formula: Among them, M H The equivalent matrix elastic modulus, i is the phase or pore space number of minerals such as quartz, clay, carbonate, and pyrite, N=5, f i M represents the volume content of the i-th medium. i This represents the elastic modulus of the i-th medium.
3. The method according to claim 1, characterized in that, The bulk modulus and shear modulus of the organic skeleton are determined by integrals according to the following formulas: The initial condition is K * (0) = K1 and μ * (0) = μ1, where K1 and μ1 are the bulk modulus and shear modulus of the main phase material, respectively; y, K2, and μ2 are the volume content, bulk modulus, and shear modulus of the included material, respectively; K * and u * In order, they are the volume differential equivalent modulus and the shear differential equivalent modulus, P( *2 )(y) and Q( *2 (y) is the geometric factor of the inclusion.
4. The method according to claim 1, characterized in that, The bulk modulus and shear modulus of saturated fluid shale are determined according to the following formulas: in, Q1=1+μ s / ζ, Where P1 and Q1 correspond to the volume factors of spherical pores, while P2 and Q2 are approximately corresponding to the volume factors of coin-shaped fissures. Porosity φ is divided into hard porosity φ s and soft porosity φ c Porosity = hard pores + soft pores; the bulk modulus and shear modulus of shale matrix minerals are K0 and K1, respectively. s and μ s The bulk modulus of the fluid is K. f The aspect ratio of the fracture is α, and the volume ratio of the fracture is... It is the bulk modulus of saturated fluid shale. Ks is the shear modulus in saturated fluid shale state, and Ks is the background matrix bulk modulus. β m ζ and ζ are intermediate variables connecting the equations.
5. The method according to claim 1, characterized in that, Longitudinal wave V of saturated fluid rock p and transverse wave velocity V s Determine according to the following formula: Where ρ is the bulk density of rock under saturated fluid conditions, K is the bulk modulus of shale under saturated fluid conditions, and μ is the shear modulus of shale under saturated fluid conditions.
6. The method according to claim 1, characterized in that, The parameters in the method for predicting the transverse and longitudinal wave velocities of marine-continental transitional shale rocks have been modified.
7. A device for predicting the transverse and longitudinal wave velocities of marine-continental transitional shale rocks, characterized in that, include: The acquisition module is used to obtain the porosity, density, and volume contents of quartz, clay, carbonate rocks, and pyrite in marine-continental transitional shale rocks. The first processing module is used to determine the equivalent matrix elastic modulus based on porosity and the volume contents of quartz, clay, carbonate rock and pyrite. The second processing module is used to determine the bulk modulus and shear modulus of the organic matter skeleton based on the bulk modulus and shear modulus of the main phase material and the volume content, bulk modulus and shear modulus of the inclusions. The third processing module is used to obtain the bulk modulus and shear modulus of shale matrix minerals based on the equivalent matrix elastic modulus, the bulk modulus and shear modulus of the organic matter skeleton. The fourth processing module is used to determine the bulk modulus and shear modulus of saturated fluid shale by mixing the fluid, shale matrix minerals, and hard pores and fractures.
8. The apparatus according to claim 7, characterized in that, include: The correction module is used to correct the parameters of the fourth processing module.
9. An electronic device, characterized in that, include: A memory and a processor, wherein a program is stored in the memory and the processor runs the program to perform the method for predicting transverse and longitudinal wave velocities of marine-continental transitional shale rocks according to any one of claims 1 to 6.
10. A program product, characterized in that, When running on a processor, it executes the method for predicting transverse and longitudinal wave velocities of marine-continental transitional shale rocks according to any one of claims 1 to 6.