Method for determining a favorable area for sandstone uranium deposits

Abstract

The embodiment of the application relates to the technical field of sandstone type uranium ore exploration, and particularly relates to a method for determining a favorable area of a sandstone type uranium ore, which comprises the following steps: collecting well logging data of an exploration area of the sandstone type uranium ore, and gradually determining argillaceous content, total porosity of the exploration area, sandstone content of a sand and shale mixed matrix, longitudinal wave time difference, transverse wave time difference and density, equivalent elastic modulus of dry rock of the exploration area, and conversion relationship between longitudinal wave velocity and transverse wave velocity of rock under saturated fluid condition and a transverse wave velocity prediction curve; then, longitudinal wave impedance, velocity ratio of longitudinal wave and transverse wave and a density model are established; according to the model, three-dimensional elastic data bodies of impedance, density and shear modulus of longitudinal wave and transverse wave are determined by inversion; and according to the three-dimensional elastic data bodies, the favorable area of the sandstone type uranium ore is determined. The method for determining the favorable area of the sandstone type uranium ore according to the embodiment of the application can effectively improve the prediction accuracy of a favorable area of a sandstone type uranium ore.

Description

Technical Field

[0001] The embodiments of this application relate to the field of sandstone-type uranium exploration technology, and more particularly to a method for determining favorable areas of sandstone uranium deposits. Background Technology

[0002] Seismic exploration is one of the most effective techniques for exploring sandstone-type uranium deposits, and seismic inversion is a crucial component of this technology. Sandstone-type uranium deposits undergo clay alteration in their mineralization environment, and the organic carbon content in this environment also increases. Traditional post-stack impedance retrieval techniques are insufficient for effectively evaluating the complex mineralization environment characteristics of concealed sandstone uranium deposits. Summary of the Invention

[0003] This application provides a method for determining favorable areas for sandstone uranium deposits, aiming to improve the accuracy of sandstone uranium mineralization prediction.

[0004] According to embodiments of this application, a method for determining favorable areas of sandstone uranium deposits is provided, illustrated in conjunction with well FZK497-255 and 3D seismic data of the Qiharigetu exploration area in the Erlian Basin. The method includes: collecting pre-stack angle gather 3D seismic data and post-stack 3D seismic data of the sandstone uranium exploration area, as well as well logging data from boreholes in the exploration area; determining the clay content of the exploration area based on the well logging data; determining the total porosity of the exploration area based on the clay content and well logging data; determining the sandstone content of the sand-mud mixed matrix in the exploration area based on the total porosity and clay content; determining the P-wave transit time, S-wave transit time, and density of the sand-mud mixed matrix based on the well logging data, total porosity, clay content, and sandstone content; and determining the isostatic properties of the sand-mud mixed matrix based on the P-wave transit time, S-wave transit time, and density. Effective elastic modulus; based on total porosity, determine the equivalent elastic modulus of dry rock in the exploration area; based on the equivalent elastic modulus of dry rock and saturated fluid matrix in the exploration area, as well as total porosity, determine the predicted P-wave velocity and S-wave velocity of rock under saturated fluid conditions, and the conversion relationship between the two; based on the P-wave velocity curve in well logging data and the predicted P-wave velocity curve of rock under saturated fluid conditions, determine the predicted S-wave velocity curve; based on the predicted P-wave velocity curve, well logging data, and pre-stack angle gather 3D seismic data and post-stack 3D seismic data, establish P-wave impedance, P-wave and S-wave velocity ratio, and density models; based on the models, determine the impedance, density, shear modulus, and Young's modulus of P-wave and S-wave; based on the impedance, density, shear modulus, and Young's modulus of P-wave and S-wave, determine the favorable areas of sandstone uranium deposits.

[0005] The method for determining favorable areas of sandstone uranium deposits according to the embodiments of this application can effectively improve the prediction accuracy of favorable areas for sandstone uranium mineralization, thereby guiding the study of the mineralization environment of sandstone uranium deposits. Attached Figure Description

[0006] Figure 1 This is a flowchart of a method for determining a favorable area of ​​sandstone uranium deposits according to an embodiment of this application;

[0007] Figure 2 The predicted density, longitudinal wave, and transverse wave curves of the sand-mud mixture matrix according to the embodiments of this application;

[0008] Figure 3 The distribution of favorable sandstone uranium deposits as predicted according to embodiments of this application. Detailed Implementation

[0009] To make the objectives, technical solutions, and advantages of this application clearer, the technical solutions of this application will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only one embodiment of this application, and not all embodiments. All other embodiments obtained by those skilled in the art based on the described embodiments of this application without creative effort are within the scope of protection of this application.

[0010] It should be noted that, unless otherwise defined, the technical or scientific terms used in this application should have the ordinary meaning understood by a person with ordinary skill in the art to which this application pertains. Where the terms "first," "second," etc., are used throughout the text, they are used only to distinguish similar objects and should not be construed as indicating or implying their relative importance, order of precedence, or implicitly specifying the number of technical features indicated. It should be understood that the data in the descriptions of "first," "second," etc., can be interchanged where appropriate. Where "and / or" appears throughout the text, it means that it includes three parallel solutions. Taking "A and / or B" as an example, it includes solution A, solution B, or a solution that simultaneously satisfies A and B.

[0011] The mineralization environment of sandstone-type uranium deposits will undergo changes such as clay alteration and increased organic carbon content. These changes will lead to alterations in the physical properties of the uranium mineralization environment. Traditional methods may struggle to identify these changes in physical properties, thus traditional post-stack impedance inversion techniques are insufficient for effectively evaluating the complex mineralization environment characteristics of concealed sandstone uranium deposits and for effectively predicting favorable uranium mineralization areas.

[0012] This application proposes to improve the accuracy of sandstone uranium mineralization prediction by using rock seismic physics data collection, analysis, and prediction indicators for the detection and evaluation of uranium mineralization environments.

[0013] Embodiments of this application provide a method for determining favorable areas of sandstone uranium deposits, referring to... Figure 1 ,include:

[0014] Step S101: Collect pre-stack angle gather 3D seismic data and post-stack 3D seismic data of the sandstone uranium deposit exploration area, as well as well logging data of the boreholes in the exploration area.

[0015] Step S102: Determine the clay content of the exploration area based on the well logging data.

[0016] Step S103: Determine the total porosity of the exploration area based on the clay content and well logging data.

[0017] Step S104: Determine the sandstone content of the sand-mud mixed matrix in the exploration area based on the total porosity and mud content.

[0018] Step S105: Based on the well logging data, total porosity, clay content, and sandstone content, determine the P-wave transit time, S-wave transit time, and density of the sand-mud mixed matrix.

[0019] Step S106: Determine the equivalent elastic modulus of the sand-mud mixture matrix based on the longitudinal wave transit time, transverse wave transit time, and density.

[0020] Step S107: Determine the equivalent elastic modulus of the dry rock in the exploration area based on the total porosity.

[0021] Step S108: Based on the equivalent elastic modulus and total porosity of the dry rock and saturated fluid matrix in the exploration area, determine the predicted longitudinal wave velocity and transverse wave velocity of the rock under saturated fluid conditions, as well as the conversion relationship between the two.

[0022] Step S109: Determine the predicted shear wave velocity curve based on the P-wave velocity curve in the well logging data and the predicted P-wave velocity curve of the rock under saturated fluid conditions.

[0023] Step S110: Based on the P-wave and S-wave velocity prediction curves, well logging data, and pre-stack angle gather 3D seismic data and post-stack 3D seismic data, establish P-wave impedance, P-wave and S-wave velocity ratio, and density models.

[0024] Step S111: Determine the impedance, density, shear modulus, and Young's modulus of the longitudinal and transverse waves based on the longitudinal wave impedance, the velocity ratio of the longitudinal and transverse waves, and the density model.

[0025] Step S112: Determine the favorable areas of sandstone uranium deposits based on the impedance, density, shear modulus, and Young's modulus of the longitudinal and transverse waves.

[0026] Specifically, in step S101, pre-stack angle gather 3D seismic data and post-stack 3D seismic data, as well as borehole logging data within the 3D seismic exploration area, are collected in the sandstone-type uranium deposit exploration area. The quality of the 3D seismic data and the types of logging parameters are confirmed, and it is determined whether logging data on clay content and porosity are present. In this embodiment, the borehole logging data collected includes sonic logging, natural gamma ray logging, resistivity logging, and density logging, but does not include clay content and porosity logging parameters. High-quality 3D seismic data is more beneficial to the accuracy of subsequent results. Conventional signal-to-noise ratio analysis methods can be used to analyze the 3D seismic data to select high-quality data as input data for subsequent work.

[0027] The collected logging data does not include clay content parameters. Therefore, the clay content is determined using existing logging data. Specifically, in step S102, the determination is carried out in two cases: First, in the case where there is no uranium mineralization zone in the borehole, the clay content Vsh is determined based on the gamma logging data GR. First, the maximum value GRmax and the minimum value GRmin in the gamma logging curve GR data are selected, and then Vsh is determined using the following formula:

[0028] Vsh=(2a*(GR-GRmin) / (GRmax-GRmin)-1) / (2a-1),

[0029] The range of values ​​for a is 2 to 3.7.

[0030] On the other hand, when there is a uranium-mineralized section in the borehole, based on the Vsh obtained in the previous step, cross-analysis is performed on the two sets of data points, Vsh and resistivity RT, which have good correlation with the non-uranium-mineralized section, to obtain the conversion relationship A between the two parameters, clay content and resistivity. In the uranium-mineralized section, the resistivity is converted into clay content using the conversion relationship A to obtain the corrected clay content vc.

[0031] Specifically, in the non-mineralized anomaly section of the well in this case, the data points of Vsh and RT were intersected on a planar graph using Excel. A trend line formula was added, resulting in the transformation relationship A: Vsh = 0.026RT - 0.1239. Then, in the uranium-mineralized section, the corrected clay content vc was obtained based on RT using transformation relationship A. Finally, the corrected clay content vc was used to replace the original Vsh value in the uranium-mineralized section, forming a new clay content curve vc.

[0032] In step S103, based on the VC logging curve determined in the previous step and the collected density logging curve Den, the total porosity Φ is determined using the following formula:

[0033]

[0034] ρ bFor the density curve actually measured in the well logging data, ρ ma The constant is 2.65 g / cc, ρ sh The constant is 2.6 g / cc, ρ f It is a constant of 1.10958 g / cc.

[0035] In step S104, the sandstone content of the sand-mud mixed matrix in the exploration area is determined based on the total porosity and clay content, and it satisfies the following expression:

[0036] vs = 1 - vc - Φ

[0037] vs represents the sandstone content of the sand-mud mixed matrix, vc represents the corrected mud content, and Φ represents the total porosity of the exploration area.

[0038] In step S105, based on well logging data and the total porosity, clay content, and sandstone content, the P-wave transit time, S-wave transit time, and density of the sandstone-mudstone matrix mixture are determined, and these parameters satisfy the following expression:

[0039] Tpm=165vs / (1-Φ)+293vc / (1-Φ),

[0040] Tsm=244vs / (1-Φ)+609vc / (1-Φ),

[0041] ρm=2.65vs / (1-Φ)+2.6vc / (1-Φ),

[0042] Tpm represents the P-wave transit time of the sand-mud mixture matrix, vs represents the sandstone content, vc represents the corrected clay content, Φ represents the total porosity of the exploration area, Tsm represents the P-wave transit time of the sand-mud mixture matrix, and ρm represents the density of the sand-mud mixture matrix. Figure 2 As shown in Figure 21.

[0043] In step S106, in the step of determining the equivalent elastic modulus of the sand-mud mixture matrix based on the longitudinal wave transit time, the transverse wave transit time, and the density, it satisfies the following expression:

[0044] Km=ρm*1 / Tpm 2 -(4 / 3)(1 / Tsm 2 )],

[0045] μm=ρm(1 / Tsm 2 ),

[0046] Km is the equivalent elastic modulus of the sand-mud mixture matrix, Tpm is the longitudinal wave transit time of the sand-mud mixture matrix, ρm is the density of the sand-mud mixture matrix, and μm is the equivalent shear modulus of the sand-mud mixture matrix.

[0047] In step S107, in the step of determining the equivalent elastic modulus of the dry rock in the exploration area based on the total porosity, it satisfies the following expression:

[0048]

[0049]

[0050]

[0051] Among them, K d Let ν be the equivalent elastic modulus of the dry rock, λ be the Poisson's ratio, Lamé coefficient, and shear modulus of the rock matrix, respectively, α be a constant ranging from 0.3 to 0.7, and C be the coordination number, C = 25.983 * Φ. 2 -43.764A*Φ+21.672, where Φ is the total porosity, P is the hydrostatic confining pressure, P=0.0087*depth, and depth is the burial depth, μ d Let A be the equivalent shear modulus of dry rock, and let A be a constant.

[0052] In step S108, in the step of determining the predicted P-wave velocity and S-wave velocity of the rock under saturated fluid conditions and the conversion relationship between them based on the equivalent elastic modulus and total porosity of the dry rock and saturated fluid matrix in the exploration area, the following expression is satisfied:

[0053] Vp_sat=((Ksat+4μsat / 3) / ρs)1 / 2,

[0054] Vs_sat=(μsat / ρs)1 / 2,

[0055]

[0056] μ sat =μ d ,

[0057] ρ s =ρ m (1-Φ)+1.10958Φ,

[0058] X = Vp_sat / Vs_sat

[0059] Where Vp_sat is the longitudinal wave velocity of the rock under saturated fluid conditions, and K sat μ is the coefficient. sat ρ is a coefficient. s K is a coefficient. d K is the equivalent elastic modulus of dry rock. m ρ is the equivalent elastic modulus of the sand-mud mixture matrix, Φ is the total porosity, and ρ is the total porosity. m K represents the density of the sand-mud mixture matrix.fl X is the bulk modulus of the fluid in the pores, with a value of 3.17 GPa, and X is the conversion relationship between the longitudinal wave velocity and the transverse wave velocity of the rock under saturated fluid conditions.

[0060] In step S109, in the step of determining the predicted P-wave velocity curve based on the P-wave velocity curve in the well logging data and the predicted P-wave velocity curve of the rock under saturated fluid conditions:

[0061] The P-wave velocity curve Vp in the logging data is subjected to low-frequency filtering using a bandpass filter with a cutoff frequency set to (0, 0, 35, 40), resulting in the low-frequency curve Vp_low. Similarly, Vp_sat is subjected to high-frequency filtering using a bandpass filter with a cutoff frequency set to (40, 40, 9999, 9999), resulting in the high-frequency curve Vp_high. The final predicted P-wave velocity curve is Vp_pre = Vp_low + Vp_high. Figure 2 As shown in Figure 22. Then, using the P-wave and S-wave velocity conversion relationship X and the obtained P-wave velocity prediction curve, the S-wave velocity prediction curve Vs_pre=Vp_pre / X is obtained, as shown in Figure 22. Figure 2 As shown in Figure 23.

[0062] exist Figure 2 In the diagram, the vertical axis represents the logging depth, and the horizontal axis represents the predicted density, P-wave, and S-wave values.

[0063] In step S110, forward modeling records are synthesized using the predicted shear wave velocity and the collected P-wave and density logging curves. The synthesized records are then calibrated by performing wave group characteristic analysis and correlation analysis with the post-stack 3D seismic data. Seismic data interpretation of the target layer is then performed according to the calibration results to form the target layer layer interpretation data F. Simultaneously, using the calibration results, multi-well wavelet prediction is performed on all wells involved in the seismic data inversion of the exploration area using wavelet prediction software (such as GeoEast) to obtain wavelet A.

[0064] In step S101, 3D seismic data volumes of different angle gathers within the exploration area are collected and analyzed. The quality of the seismic data from each angle gather is analyzed. For example, in this case, the signal-to-noise ratio (SNR) of the pre-stack seismic data from 0 to 90 degrees was analyzed. The analysis results show that the SNR of angle gather data less than 12 degrees and greater than 30 degrees is low. Therefore, angle gather data from 12 to 30 degrees are selected for pre-stack inversion. Based on this, the data is divided into three angle gathers: near (less than 12-18 degrees), intermediate (18-24 degrees), and far (24-30 degrees). The selection of angle gather data is based on the SNR of the seismic data from different angle gathers.

[0065] In step S110, based on the predicted wavelet A from all boreholes in the exploration area and the seismic data from the three angle gathers selected in step S101, the synthetic records are calibrated according to the above process. Then, based on the calibration results, wavelet prediction software (such as GeoEast) is used to predict the wavelets of the three angle gather seismic data, obtaining wavelets B1, B2, and B3 of the three angle gather seismic data. Finally, by combining the well logging curve data Vp, Vs_pre, Den, and the layer interpretation data F, a low-frequency model M for pre-stack simultaneous inversion is established using the modeling function of the seismic inversion software. This model mainly includes P-wave impedance, P-wave and S-wave velocity ratio, and density model.

[0066] In step S111, the pre-stack inversion module of the seismic inversion software is used to perform pre-stack inversion calculations on the three corner gather seismic stacking data, which can obtain three-dimensional data volumes of impedance, density, shear modulus and Young's modulus of P-waves and S-waves.

[0067] In step S111, before performing pre-stack inversion calculation, the parameter settings need to be tested and relevant values ​​are preferred. The main parameter settings in the seismic inversion software are: error of 0.01 to 0.015, signal-to-noise ratio of 10 to 20, wavelet ratio of 0.8 to 1.2, cutoff frequency of 10 to 15 Hz, and soft constraint uncertainty of 10% to 20%.

[0068] In step S112, the well logging profile is analyzed by analyzing the product of shear modulus and density and Young's modulus data (connected well profile and isochronous surface slice analysis). The region with a shear modulus and density product value less than 6 (Gpa*g / cc) is marked as favorable region 1, and the region with a Young's modulus parameter value less than 7e+06Gpa is marked as favorable region 2. The two favorable regions 1 and 2 are superimposed. The overlapping area of ​​the two favorable regions is predicted to be a Class I mineralization prospective area with great mineralization potential. The area with only one favorable region is predicted to be a Class II mineralization favorable area with less mineralization potential. Figure 3 To predict the product of shear modulus and density, and the data distribution of Young's modulus parameters in the well profile, the light-colored area 31 is the favorable area.

[0069] In some implementations, well profiles can be generated in three-dimensional space or two-dimensional space. Generally, a profile map refers to a two-dimensional map obtained by unfolding and straightening a well profile generated in three-dimensional space. A profile map contains two parts of information. The first part is the logging data from each well. The second part is the measurement information between the wells, such as seismic data, or information calculated using a particular method.

[0070] In some implementations, layer-by-layer slicing is performed along or parallel to the layers obtained by tracing the seismic phase axis; time slicing is the display of seismic data volume along a fixed seismic travel time, with the slicing direction perpendicular to the time axis. The displayed strata have time-transition properties, reflecting the exposure of different strata at the same burial depth (equal t0), and have unique advantages in understanding underground structural morphology and identifying certain special geological phenomena.

[0071] The present invention has been described in detail above with reference to the accompanying drawings and embodiments. However, the present invention is not limited to the above embodiments, and various changes can be made within the scope of knowledge possessed by those skilled in the art without departing from the spirit of the present invention. All contents not described in detail in the present invention can be derived from existing technologies.

Claims

1. A method for determining a favorable area of sandstone uranium deposit, comprising the steps of: collecting pre-stack angle gather 3D seismic data and post-stack 3D seismic data of an exploration area of the sandstone uranium deposit and well logging data of a borehole in the exploration area; determining shale content of the exploration area according to the well logging data; determining total porosity of the exploration area according to the shale content and the well logging data; determining sandstone content of a sand-shale mixed matrix of the exploration area according to the total porosity and the shale content; determining P-wave time difference, S-wave time difference and density of the sand-shale mixed matrix according to the well logging data and the total porosity, the shale content and the sandstone content; determining equivalent elastic modulus of the sand-shale mixed matrix according to the P-wave time difference, the S-wave time difference and the density; determining equivalent elastic modulus of dry rock of the exploration area according to the total porosity; determining predicted P-wave velocity and S-wave velocity of rock under saturated fluid condition and a conversion relationship therebetween according to equivalent elastic modulus of the dry rock, saturated fluid matrix and total porosity of the exploration area; determining S-wave velocity prediction curve according to P-wave velocity curve in the well logging data and predicted P-wave velocity curve of rock under saturated fluid condition; establishing P-wave impedance, velocity ratio of P-wave and S-wave and density model according to the S-wave velocity prediction curve, the well logging data and the pre-stack angle gather 3D seismic data and the post-stack 3D seismic data; determining impedance, density, shear modulus and Young's modulus of P-wave and S-wave according to the model; determining a favorable area of sandstone uranium deposit according to the impedance, density, shear modulus and Young's modulus of P-wave and S-wave.

2. The method of claim 1, wherein, In the step of determining shale content of the exploration area according to the well logging data, the following expression is satisfied: Vsh = (2 a*(GR-GRmin) / (GRmax-GRmin ) -1) / (2 a -1) Vsh represents shale content, GR represents gamma data in the well logging data, GRmin represents minimum value in the gamma data in the well logging data, GRmax represents maximum value in the gamma data in the well logging data, and a is a constant, and the value range of a is 2-3.

7.

3. The method of claim 2, wherein, In the step of determining shale content of the exploration area according to the well logging data, the determined shale content is corrected in the following manner: vc = 0.026RT - 0.1239 wherein vc is the corrected shale content, and RT is resistivity in the well logging data.

4. The method of claim 3, wherein, In the step of determining total porosity of the exploration area according to the shale content and the well logging data, the following expression is satisfied: wherein, is a constant 2.65 g / cc, is a constant 2.65 g / cc, is a constant 2.65 g / cc, is a constant 1.10958 g / cc.

5. The method of claim 4, wherein, In the step of determining sandstone content of a sand-shale mixed matrix of the exploration area according to the total porosity and the shale content, the following expression is satisfied: vs = 1 - vc- Where, vs is the sandstone content of the sand and shale mixed matrix, vc is the corrected shale content, is the total porosity of the survey area.

6. The method of claim 5, wherein, In the step of determining P-wave time difference, S-wave time difference and density of the sand-shale mixed matrix according to the well logging data and the total porosity, the shale content and the sandstone content, the following expressions are satisfied: Tpm = 165 vs / (1-Φ) + 293 vc / (1-Φ), Tsm = 244 vs / (1-Φ) + 609 vc / (1-Φ), ρm = 2.65 vs / (1-Φ) + 2.6 vc / (1-Φ), where Tpm is the P-wave time of the sand-shale mixture, vs is the sand content, and vc is the corrected shale content, where φt is the total porosity of the survey area, Tsm is the S-wave time of the sand-shale mixture, and pm is the density of the sand-shale mixture.

7. The method of claim 6, wherein, In the step of determining the equivalent elastic modulus of the sand-mud mixed matrix according to the P-wave time difference, the S-wave time difference and the density, the following expression is satisfied: Km= pm [1 / Tpm 2 -(4 / 3)(1 / Tsm 2 )], μm = pm(1 / Tsm 2 ), Wherein, Km is the equivalent elastic modulus of the sand-mud mixed matrix, Tpm is the P-wave time difference of the sand-mud mixed matrix, ρm is the density of the sand-mud mixed matrix, and μm is the equivalent shear modulus of the sand-mud mixed matrix.

8. The method of claim 7, wherein, In the step of determining the equivalent elastic modulus of the dry rock of the exploration area according to the total porosity, the following expression is satisfied: ， ， ， where K d is the equivalent elastic modulus of dry rock, v, l, m are Poisson's ratio, Lame's coefficient, shear modulus of rock matrix respectively, a is a constant, its value range is 0.3-0.7, C is coordination number, C = 25.983 2 - 43.764A + 21.672, wherein P is hydrostatic confining pressure, P = 0.0087*depth, depth is burial depth, m d is the equivalent shear modulus of dry rock, A is a constant.

9. The method of claim 8, wherein, In the step of determining the predicted P-wave velocity and S-wave velocity of the rock under the saturated fluid condition and the conversion relationship therebetween according to the equivalent elastic modulus of the dry rock and the saturated fluid matrix of the exploration area and the total porosity, the following expressions are satisfied: Vp_sat =((Ksat+4μsat / 3) / ρs)1 / 2, Vs_sat =(μsat / ρs) 1 / 2, ， ， = p m (1 - Φ) + 1.10958 Φ X=Vp_sat / Vs_sat where Vp sat is the P-wave velocity of the rock under saturated fluid condition, K sat is a coefficient, , p s is a coefficient, K d is the equivalent elastic modulus of dry rock, K m is the equivalent elastic modulus of sand-shale mixture matrix, is the total porosity, μ d is the equivalent shear modulus of dry rock, p m is the density of sand-shale mixture matrix, K fl is the bulk modulus of fluid in the pore, with a value of 3.17 GPa, and X is the conversion relationship between P-wave and S-wave velocities of the rock under saturated fluid condition.

10. The method of claim 9, wherein, In the step of determining the S-wave velocity prediction curve according to the P-wave velocity curve in the logging data and the predicted P-wave velocity curve of the rock under the saturated fluid condition, the following steps are included: The P-wave velocity curve Vp in the logging data is subjected to low-frequency filtering to obtain a low-frequency curve Vp_low of Vp; Vp_sat is subjected to high-frequency filtering by using a band-pass filter to obtain a high-frequency curve Vp_high of Vp_sat, and finally Vp_pre=Vp_low+Vp_high is obtained, then the S-wave prediction result Vs_pre=Vp_pre / X is obtained by using the P-S wave conversion relationship X and the obtained P-wave prediction result Vp_pre.

11. The method of claim 1, comprising the following steps: In the step of determining the favorable area of the sandstone uranium deposit according to the impedance, density, shear modulus and Young's modulus of the P-wave and S-wave, the following steps are further included: The profile formed by the logging data is analyzed according to the product of the shear modulus and the density and the Young's modulus; The area where the product of the shear modulus and the density is less than a predetermined value is selected as a first favorable area; The area where the value of the Young's modulus is less than a predetermined value is selected as a second favorable area; The overlapping area between the first favorable area and the second favorable area is determined, and the overlapping area is the favorable area for mineralization.

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