Rock quality factor analysis method and program product based on double reference samples

Abstract

The application discloses a rock quality factor analysis method and program product based on double reference samples, and the method comprises the following steps: firstly, collecting ultrasonic propagation signals of a first reference sample, a second reference sample and a rock sample to be measured; then performing frequency spectrum transformation on the ultrasonic propagation signals of the samples to obtain a first reference sample amplitude spectrum, a second reference sample amplitude spectrum and a rock sample amplitude spectrum to be measured; using the first reference sample amplitude spectrum, the second reference sample amplitude spectrum and the rock sample amplitude spectrum to be measured to construct a first amplitude logarithmic ratio and a second amplitude logarithmic ratio; finally, performing linear fitting on the relationship between the first amplitude logarithmic ratio and the frequency and the relationship between the second amplitude logarithmic ratio and the frequency, and obtaining a quality factor value corresponding to the rock sample to be measured according to the fitting result. The application realizes high-reliable measurement of the quality factor value of the sample to be measured, and effectively improves the characterization ability of the measurement result to the real attenuation characteristics.

Description

Technical Field

[0001] This invention relates to the field of rock physical testing technology, and in particular to a rock quality factor analysis method and program product based on dual reference samples. Background Technology

[0002] The quality factor Q is an important parameter characterizing the energy attenuation capability of a medium's wave motion, and it is of great significance in rock physics, oil and gas reservoir evaluation, material damage identification, and wave propagation mechanism research.

[0003] In existing technologies, the Q-value measurement of rock samples often adopts the single reference sample spectrum ratio method. That is, under the same test conditions, the amplitude spectrum of the rock sample to be tested is compared with that of a reference sample (such as an aluminum sample), and the Q-value of the rock sample to be tested is inverted based on the linear relationship between the logarithmic amplitude ratio and the frequency.

[0004] refer to Figure 2 The schematic diagram shown illustrates the principle of the traditional single-reference sample spectral ratio method. Its basic steps include: 1. Acquiring ultrasonic transmission signals from the reference sample and the test sample respectively; 2. Performing time window truncation and Fourier transform on the acquired time-domain signals to obtain the amplitude spectrum; 3. Calculating the logarithmic amplitude ratio between the test sample and the reference sample; 4. Performing linear fitting on the frequency within the selected frequency band and calculating the Q value of the test sample from the slope.

[0005] In the above-mentioned reference sample measurement method, the geometry and physical parameters of the reference sample and the test sample need to be as similar as possible. When the signal propagates the same distance x in both samples, the amplitude spectrum of the received signal in the two samples can be expressed by the following formulas: , ,in, and These represent the received signal amplitude spectra of the reference sample and the test sample, respectively. For the source spectrum, Let G be the attenuation coefficient, G be the diffraction effect factor (geometric diffusion factor), and w be the instrument response factor. Dividing the above two equations and taking the natural logarithm yields: Generally, materials with lower attenuation are chosen as reference samples (such as aluminum samples), therefore, it is possible to... Approximately 0. For the constant Q model, the attenuation coefficient is... The following relationship exists between it and the quality factor: Where v is the velocity of the test sample. Then, the attenuation coefficient... Substituting the relationship between the quality factor and the logarithm into the equation yields a linear relationship between the logarithm ratio of amplitude and frequency: ,in, The Q value of the test sample can be calculated using the slope relationship.

[0006] While existing single-reference methods are simple in structure and easy to implement, they still have significant shortcomings. First, the entire measurement chain relies on only one reference sample, lacking internal calibration and self-consistent verification mechanisms, thus failing to effectively determine whether the inversion results truly reflect the attenuation characteristics of the tested rock sample. Second, fluctuations in the excitation source waveform, changes in transducer response, differences in coupling states, gain settings, time window truncation methods, frequency band selection, and even minor deviations in geometric conditions can all directly affect the final Q value. Third, when the tested rock is heterogeneous, weakly anisotropic, or the test signal contains noise, the slope of the single spectral ratio relationship is prone to instability, leading to calculation results deviating from the true value. Especially when the attenuation characteristics of the tested rock sample are difficult to estimate in advance, existing methods struggle to simultaneously ensure accuracy, stability, and verifiability.

[0007] Therefore, there is an urgent need to invent a new method for Q-value measurement that can take into account measurement accuracy, result reliability, and self-calibration capability in actual physical measurement processes, so as to solve the problem that existing technologies cannot simultaneously achieve accuracy, stability, and verifiability. Summary of the Invention

[0008] In view of this, embodiments of the present invention provide a method and program product for rock quality factor analysis based on dual reference samples, which at least partially solves the problems existing in the prior art.

[0009] Other features and advantages of the invention will become apparent from the following detailed description, or may be learned in part by practice of the invention.

[0010] To achieve the above objectives, the embodiments of the present invention provide the following technical solutions:

[0011] According to a first aspect of the present invention, a method for analyzing rock quality factors based on dual reference samples is provided, the method comprising:

[0012] The ultrasonic propagation signals of the first reference sample, the second reference sample, and the rock sample to be tested were collected;

[0013] The ultrasonic propagation signals of each sample were processed by spectral transformation to obtain the amplitude spectrum of the first reference sample, the amplitude spectrum of the second reference sample, and the amplitude spectrum of the sample to be tested.

[0014] A first amplitude logarithmic ratio is constructed using the amplitude spectrum of the first reference sample, the amplitude spectrum of the second reference sample, and the amplitude spectrum of the sample to be tested.

[0015] A second amplitude logarithmic ratio is constructed using the amplitude spectrum of the second reference sample and the amplitude spectrum of the sample to be tested;

[0016] Linear fitting is performed on the relationship between the first amplitude logarithmic ratio and frequency, and the relationship between the second amplitude logarithmic ratio and frequency, respectively. Based on the slope parameter obtained from the linear fitting, a two-variable linear equation is constructed, consisting of the slope parameter, the quality factor of the second reference sample, and the quality factor value of the rock sample to be tested. By solving the equation, the quality factor of the second reference sample and the corresponding quality factor value of the rock sample to be tested can be obtained. The calculated quality factor of the second reference sample is compared with the known value to obtain a stable and accurate quality factor of the rock sample to be tested.

[0017] Furthermore, the first reference sample is a sample whose quality factor value is greater than a preset quality factor threshold and whose attenuation coefficient is less than a preset attenuation threshold.

[0018] The second reference sample is a homogeneous isotropic sample with a pre-calibrated quality factor value and stable physicochemical properties.

[0019] Furthermore, the ultrasonic propagation signals of each sample are subjected to spectral transformation processing to obtain the amplitude spectrum of the first reference sample, the amplitude spectrum of the second reference sample, and the amplitude spectrum of the sample to be tested, including:

[0020] The ultrasonic propagation signal of each sample is time-windowed to obtain the effective signal corresponding to each sample. The effective signal is the first wave transmission signal or the reflection signal.

[0021] The effective signals corresponding to each sample are subjected to spectral transformation processing to obtain the amplitude spectrum of the first reference sample. Amplitude spectrum of the second reference sample and the amplitude spectrum of the sample to be tested ;

[0022] The expression for the amplitude spectrum of the first reference sample is: Where x is the propagation distance, For the source spectrum, The attenuation coefficient corresponding to the first reference sample. is the geometric diffusion factor corresponding to the first reference sample, f is the frequency, and w is the instrument response factor;

[0023] The expression for the amplitude spectrum of the second reference sample is: ,in, The attenuation coefficient corresponding to the second reference sample. The geometric diffusion factor corresponding to the second reference sample;

[0024] The expression for the amplitude spectrum of the sample to be tested is: ,in, The attenuation coefficient corresponding to the rock sample to be tested. denoted as the geometric diffusion factor for the rock sample to be tested.

[0025] Further, using the amplitude spectrum of the first reference sample, the amplitude spectrum of the second reference sample, and the amplitude spectrum of the sample to be tested, a first amplitude logarithmic ratio is constructed, including:

[0026] Using the amplitude spectrum of the first reference sample, the amplitude spectrum of the second reference sample, and the amplitude spectrum of the sample to be tested, a first amplitude logarithmic ratio is constructed. The calculation formula is: ,in, .

[0027] Further, using the amplitude spectrum of the second reference sample and the amplitude spectrum of the sample to be tested, a second amplitude logarithmic ratio is constructed, including:

[0028] Using the amplitude spectrum of the second reference sample and the amplitude spectrum of the sample to be tested, a second amplitude logarithmic ratio is constructed. The calculation formula is: ,in, .

[0029] Furthermore, linear fitting is performed on the relationship between the first amplitude logarithmic ratio and frequency, and the relationship between the second amplitude logarithmic ratio and frequency, respectively. Based on the slope parameter obtained from the linear fitting, a two-variable linear equation is constructed, consisting of the slope parameter, the quality factor of the second reference sample, and the quality factor value of the rock sample to be tested. By solving the equation, the quality factor of the second reference sample and the corresponding quality factor value of the rock sample to be tested can be obtained, including:

[0030] A linear fit is performed on the relationship between the first amplitude logarithmic ratio and the frequency to obtain the first slope. The fitting process is as follows: , , , , Where Q is the quality factor value corresponding to the sample;

[0031] A linear fit was performed on the relationship between the second amplitude logarithmic ratio and the frequency to obtain the second slope. The fitting process is as follows: , ;

[0032] Using the first slope and the second slope, the quality factor value corresponding to the rock sample to be tested is calculated. The calculation formula is: ;

[0033] Using the first slope and the second slope, the calculated quality factor value corresponding to the second reference sample is obtained. The calculation formula is: .

[0034] Furthermore, the calculated quality factor of the second reference sample is compared with the known value to obtain a stable and accurate quality factor for the tested rock sample, including:

[0035] Determine the quality factor calibration value and the calculated quality factor value of the second reference sample. Is the deviation between them less than or equal to the preset deviation threshold?

[0036] If the quality factor calibration value of the second reference sample and the calculated quality factor value If the deviation between the two values ​​is less than or equal to a preset deviation threshold, then the quality factor value of the rock sample to be tested is... efficient;

[0037] If the quality factor calibration value of the second reference sample and the calculated quality factor value If the deviation between the values ​​is greater than a preset deviation threshold, then the quality factor value of the rock sample to be tested will be... invalid.

[0038] According to a second aspect of the present invention, a computer program product is provided, the computer program product comprising a computing program stored on a non-transitory computer-readable storage medium, the computer program comprising program instructions that, when executed by a computer, cause the computer to perform the steps of a rock quality factor analysis method based on dual reference samples as described in any of the preceding claims.

[0039] This invention provides a method and program product for rock quality factor analysis based on dual reference samples. The method includes: first, acquiring ultrasonic propagation signals of a first reference sample, a second reference sample, and a rock sample to be tested; then, performing spectral transformation processing on the ultrasonic propagation signals of each sample to obtain the amplitude spectrum of the first reference sample, the amplitude spectrum of the second reference sample, and the amplitude spectrum of the rock sample to be tested, respectively; using the amplitude spectra of the first reference sample, the second reference sample, and the rock sample to be tested, constructing a first amplitude logarithmic ratio and a second amplitude logarithmic ratio; finally, performing linear fitting on the relationships between the first amplitude logarithmic ratio and frequency, and the relationships between the second amplitude logarithmic ratio and frequency, respectively, and obtaining the quality factor value corresponding to the rock sample to be tested based on the fitting results. This invention achieves highly reliable measurement of the quality factor value of the rock sample to be tested, effectively improving the ability of the measurement results to characterize the true attenuation characteristics. Attached Figure Description

[0040] To more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are merely exemplary, and those skilled in the art can derive other embodiments based on the provided drawings without creative effort.

[0041] Figure 1 A schematic flowchart of a rock quality factor analysis method based on dual reference samples provided in an embodiment of the present invention;

[0042] Figure 2 A schematic diagram illustrating the principle of the traditional single-reference sample spectral ratio method provided in an embodiment of the present invention;

[0043] Figure 3 This is a schematic diagram of the noiseless forward modeling experimental results provided in an embodiment of the present invention;

[0044] Figure 4 This is a schematic diagram of the forward modeling simulation results of a noisy signal provided in an embodiment of the present invention. Detailed Implementation

[0045] 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. 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.

[0046] 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.

[0047] Figure 1 A flowchart of a rock quality factor analysis method based on dual reference samples according to an embodiment of the present invention is shown.

[0048] like Figure 1As shown, the rock quality factor analysis method based on dual reference samples according to an embodiment of the present invention may include steps S100, S200, S300 and S400.

[0049] In step S100, ultrasonic propagation signals of the first reference sample, the second reference sample, and the rock sample to be tested are acquired.

[0050] Specifically, the above steps include:

[0051] Ultrasonic propagation signals of the first reference sample, the second reference sample, and the rock sample to be tested were collected under the same testing system, the same or known propagation path, the same excitation conditions, and the same sampling conditions, and the corresponding wave velocities were measured.

[0052] The first reference sample mentioned above is a stable sample with a quality factor Q value greater than the preset quality factor threshold, an attenuation coefficient less than the preset attenuation threshold (the quality factor Q value is very large, and the attenuation coefficient can be approximately 0), and a Q value much greater than that of the rock sample to be tested. It is not limited to aluminum samples, but can also be steel, titanium alloy, quartz or other high Q stable materials.

[0053] The second reference sample mentioned above is a standard sample whose quality factor Q value has been pre-calibrated, whose physicochemical properties are stable, whose attenuation characteristics are stable, and which is easy to repeat measurement. For example, an acrylic glass sample, but not limited to acrylic glass, can also be epoxy resin, standard resin block, quartz glass or other stable materials with pre-calibrated Q values.

[0054] Preferably, the quality factor Q value of the second reference sample is in a moderate range that facilitates stable measurement, for example, 50 to 200.

[0055] Preferably, the above-mentioned reference sample is homogeneous and isotropic, and maintains stable physical and chemical properties under normal temperature testing conditions.

[0056] Next, in step S200, the ultrasonic propagation signals of each sample are subjected to spectral transformation processing to obtain the amplitude spectrum of the first reference sample, the amplitude spectrum of the second reference sample, and the amplitude spectrum of the sample to be tested.

[0057] Specifically, the above steps include:

[0058] The ultrasonic propagation signal of each sample is time-windowed to obtain the effective signal corresponding to each sample. The effective signal is preferably the first wave transmission signal, but the reflected signal or other effective wave packets with known propagation paths can also be used as needed.

[0059] Under the constant Q model, the effective signals corresponding to each sample are subjected to spectral transformation processing to obtain the amplitude spectrum of the first reference sample. Amplitude spectrum of the second reference sample and the amplitude spectrum of the sample to be tested .

[0060] The spectral transformation method used in the embodiments of the present invention is not limited to the fast Fourier transform, but can also use short-time spectrum, wavelet spectrum or other algorithms that can obtain effective amplitude spectrum.

[0061] The expression for the amplitude spectrum of the first reference sample is as follows: Where x is the propagation distance, For the source spectrum, The attenuation coefficient corresponding to the first reference sample. is the geometric diffusion factor (GDP) corresponding to the first reference sample, f is the frequency, and w is the instrument response factor.

[0062] The expression for the amplitude spectrum of the second reference sample mentioned above is: ,in, The attenuation coefficient corresponding to the second reference sample. This is the geometric diffusion factor corresponding to the second reference sample.

[0063] The expression for the amplitude spectrum of the sample to be tested is as follows: ,in, The attenuation coefficient corresponding to the rock sample to be tested. denoted as the geometric diffusion factor for the rock sample to be tested.

[0064] In step S300, a first amplitude logarithmic ratio is constructed using the amplitude spectrum of the first reference sample, the amplitude spectrum of the second reference sample, and the amplitude spectrum of the sample to be tested; a second amplitude logarithmic ratio is constructed using the amplitude spectrum of the second reference sample and the amplitude spectrum of the sample to be tested.

[0065] Specifically, the above steps include:

[0066] Using the amplitude spectra of the first reference sample, the amplitude spectra of the second reference sample, and the amplitude spectrum of the sample to be tested, a first amplitude logarithmic ratio is constructed. The calculation formula is: ,in, .

[0067] A second amplitude logarithmic ratio is constructed using the amplitude spectrum of the second reference sample and the amplitude spectrum of the sample to be tested. The calculation formula is: ,in, .

[0068] Finally, in step S400, linear fitting is performed on the relationship between the first amplitude logarithmic ratio and frequency, and the relationship between the second amplitude logarithmic ratio and frequency, respectively. Based on the slope parameter obtained from the linear fitting, a two-variable linear equation is constructed, consisting of the slope parameter, the quality factor of the second reference sample, and the quality factor value of the rock sample to be tested. By solving the equation, the quality factor of the second reference sample and the corresponding quality factor value of the rock sample to be tested can be obtained. The calculated quality factor of the second reference sample is compared with the known value to obtain a stable and accurate quality factor of the rock sample to be tested.

[0069] Specifically, the above steps include:

[0070] For the constant-Q model, the attenuation coefficient The following relationship exists between quality factor Q and Q: Where v is the velocity of the test sample, and the first reference sample has a smaller attenuation. It can be approximated as 0.

[0071] A linear fit was performed on the relationship between the logarithmic ratio of the first amplitude and the frequency to obtain the first slope. The fitting process is as follows: , , , , , where Q is the quality factor value corresponding to the sample.

[0072] A linear fit was performed on the relationship between the logarithmic ratio of the second amplitude and the frequency to obtain the second slope. The fitting process is as follows: , .

[0073] Using the first slope Second slope and and Based on the relationship, construct a linear equation in two variables: .

[0074] Using the above two-variable linear equation, the quality factor value corresponding to the rock sample to be tested is calculated. The calculation formula is: .

[0075] The fitting method in the embodiments of the present invention is not limited to ordinary linear fitting, but may also employ robust fitting, weighted fitting, and multiple measurement statistical fusion.

[0076] Using the above two linear equations in two variables, the calculated quality factor value corresponding to the second reference sample is obtained. The calculation formula is: .

[0077] Determine the calibration value and calculated value of the quality factor of the second reference sample. Whether the deviation between them is less than or equal to the preset deviation threshold; if the quality factor calibration value and the quality factor calculation value of the second reference sample are... If the deviation between the two values ​​is less than or equal to a preset deviation threshold, then the quality factor value of the rock sample to be tested is... Valid; if the quality factor calibration value and the quality factor calculation value of the second reference sample are valid. If the deviation between the values ​​is greater than a preset deviation threshold, then the quality factor value of the rock sample to be tested will be... Ineffective. Then, repeat the above process until... If the deviation is less than the preset deviation threshold, the quality factor value of the rock sample obtained at this time is... efficient.

[0078] The essential difference between this invention and existing single-reference sample methods lies not only in the addition of a standard sample, but also in the construction of two independent linear constraint relationships through a specific spectral ratio combination between the first reference sample, the second reference sample, and the rock sample to be tested. This enables a closed-loop measurement process of solving the dual slopes simultaneously, determining self-consistency, and calibrating the reference value.

[0079] The quality factor values ​​of the rock samples obtained from the analysis were verified by noiseless simulation experiments and noise-containing simulation experiments to verify the feasibility of the present invention.

[0080] (1) Noiseless simulation experiment

[0081] The first reference sample (aluminum sample, Q value 10^8), the second reference sample (plexiglass, Q value 80), and the sample to be tested (rock sample, Q value 45) were set.

[0082] Figure 3 The results of the noise-free forward modeling simulation are shown, in which, Figure 3 (a) is an analog signal. Figure 3 (b) is the amplitude spectrum of the analog signal. Figure 3 (c) represents the logarithmic ratio of the first amplitude. Figure 3 (d) is the second amplitude logarithmic ratio; by calculating K1, K2 and the known physical simulation parameters, Q2 (80) and Q3 (45) can be calculated, verifying the feasibility of the present invention.

[0083] (2) Noise-containing signal simulation experiment

[0084] Since rock samples are not isotropic media in actual measurements, their waveforms will be subject to certain interference. Therefore, a certain interference signal is added to the test sample signal in the simulation to better approximate the actual situation.

[0085] Figure 4 The results of forward modeling simulation of noisy signals are shown, in which, Figure 4 (a) is a noisy analog signal. Figure 4 (b) is the amplitude spectrum of the noisy analog signal. Figure 4 (c) represents the logarithmic ratio of the first amplitude. Figure 4 (d) is the second amplitude logarithmic ratio; by calculating K1, K2 and known physical simulation parameters, Q2 (81) and Q3 (47) can be calculated, verifying the feasibility of the present invention.

[0086] Meanwhile, since the signal contains a certain amount of noise, the Q value of the second reference sample calculated by the noisy analog signal and the Q value of the test sample both fluctuate. The Q value of the second reference sample can be used to better correct the Q value of the test sample, providing a better calibration reference value for accurate measurement of the test sample.

[0087] This invention provides a rock quality factor analysis method based on dual reference samples. By introducing a second reference sample with a pre-known Q value and stable attenuation on top of the traditional single reference sample, two independent logarithmic amplitude ratio relationships are constructed. By combining the solution of dual slopes with reference value verification, an internal calibration and self-consistent verification mechanism is added, achieving highly reliable measurement of the Q value of the sample to be tested. This reduces the impact of systematic errors, measurement errors, and calculation errors on the results, and improves the ability of the measurement results to characterize the true attenuation characteristics.

[0088] In addition, this embodiment of the invention also provides a rock quality factor analysis device based on dual reference samples. The device includes a processor and a memory; the memory is used to store one or more program instructions; the processor is used to run one or more program instructions to perform the steps of a rock quality factor analysis method based on dual reference samples as described above.

[0089] In addition, embodiments of the present invention also provide a computer-readable storage medium storing a computer program, which, when executed by a processor, implements the steps of a rock quality factor analysis method based on dual reference samples as described above.

[0090] In addition, embodiments of the present invention also provide a computer program product, which includes computer program instructions that, when executed by a processor, implement the steps of a rock quality factor analysis method based on dual reference samples as described above.

[0091] Compared with the prior art, the embodiments of the present invention have the following technical advantages:

[0092] This invention extends the traditional single slope measurement to a simultaneous solution of two slopes by constructing a dual-reference sample and a dual-logarithmic amplitude ratio, thus enabling the Q-value inversion process to have internal self-verification capability.

[0093] This invention can effectively reduce the influence of excitation source spectrum fluctuations, transducer response changes and some systematic errors on the results when constructing the spectral ratio. The residual error mainly enters the intercept term, thereby improving the stability of Q-value solution.

[0094] This invention can directly determine the reliability of the test by comparing the known Q value of the second reference sample with the calculated Q value, and can further correct the Q value of the sample to be tested.

[0095] Even when the rock sample to be tested has noise interference, weak heterogeneity, or attenuation characteristics that are difficult to estimate in advance, the present invention can still maintain good reliability of results and diagnosability of problems.

[0096] The present invention is simple to implement and can be directly deployed on existing ultrasonic rock physics testing platforms, making it highly practical for engineering applications.

[0097] Although the present invention has been described in detail above with general descriptions and specific embodiments, modifications or improvements can be made to it, which will be obvious to those skilled in the art. Therefore, all such modifications or improvements made without departing from the spirit of the present invention fall within the scope of protection claimed by the present invention.

[0098] The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention in any way. Any simple modifications, equivalent changes, or alterations made by those skilled in the art using the disclosed technical content shall fall within the protection scope of the present invention.

Claims

1. A method for analyzing rock quality factors based on dual reference samples, characterized in that, The method includes: The ultrasonic propagation signals of the first reference sample, the second reference sample, and the rock sample to be tested were collected; The ultrasonic propagation signals of each sample were processed by spectral transformation to obtain the amplitude spectrum of the first reference sample, the amplitude spectrum of the second reference sample, and the amplitude spectrum of the sample to be tested. A first amplitude logarithmic ratio is constructed using the amplitude spectrum of the first reference sample, the amplitude spectrum of the second reference sample, and the amplitude spectrum of the sample to be tested. A second amplitude logarithmic ratio is constructed using the amplitude spectrum of the second reference sample and the amplitude spectrum of the sample to be tested; Linear fitting is performed on the relationship between the first amplitude logarithmic ratio and frequency, and the relationship between the second amplitude logarithmic ratio and frequency, respectively. Based on the slope parameter obtained from the linear fitting, a two-variable linear equation is constructed, consisting of the slope parameter, the quality factor of the second reference sample, and the quality factor value of the rock sample to be tested. By solving the equation, the quality factor of the second reference sample and the corresponding quality factor value of the rock sample to be tested can be obtained. The calculated quality factor of the second reference sample is compared with the known value to obtain a stable and accurate quality factor of the rock sample to be tested.

2. The rock quality factor analysis method based on dual reference samples according to claim 1, characterized in that, The first reference sample is a sample whose quality factor value is greater than a preset quality factor threshold and whose attenuation coefficient is less than a preset attenuation threshold; The second reference sample is a homogeneous isotropic sample with a pre-calibrated quality factor value and stable physicochemical properties.

3. The rock quality factor analysis method based on dual reference samples according to claim 1, characterized in that, The ultrasonic propagation signals of each sample were subjected to spectral transformation processing to obtain the amplitude spectrum of the first reference sample, the amplitude spectrum of the second reference sample, and the amplitude spectrum of the sample to be tested, including: The ultrasonic propagation signal of each sample is time-windowed to obtain the effective signal corresponding to each sample. The effective signal is the first wave transmission signal or the reflection signal. The effective signals corresponding to each sample are subjected to spectral transformation processing to obtain the amplitude spectrum of the first reference sample. Amplitude spectrum of the second reference sample and the amplitude spectrum of the sample to be tested ; The expression for the amplitude spectrum of the first reference sample is: Where x is the propagation distance, For the source spectrum, The attenuation coefficient corresponding to the first reference sample. is the geometric diffusion factor corresponding to the first reference sample, f is the frequency, and w is the instrument response factor; The expression for the amplitude spectrum of the second reference sample is: ,in, The attenuation coefficient corresponding to the second reference sample. The geometric diffusion factor corresponding to the second reference sample; The expression for the amplitude spectrum of the sample to be tested is: ,in, The attenuation coefficient corresponding to the rock sample to be tested. denoted as the geometric diffusion factor for the rock sample to be tested.

4. The rock quality factor analysis method based on dual reference samples according to claim 3, characterized in that, Using the amplitude spectrum of the first reference sample, the amplitude spectrum of the second reference sample, and the amplitude spectrum of the sample to be tested, a first amplitude logarithmic ratio is constructed, including: Using the amplitude spectrum of the first reference sample, the amplitude spectrum of the second reference sample, and the amplitude spectrum of the sample to be tested, a first amplitude logarithmic ratio is constructed. The calculation formula is: ,in, .

5. The rock quality factor analysis method based on dual reference samples according to claim 4, characterized in that, Using the amplitude spectrum of the second reference sample and the amplitude spectrum of the sample to be tested, a second amplitude logarithmic ratio is constructed, including: Using the amplitude spectrum of the second reference sample and the amplitude spectrum of the sample to be tested, a second amplitude logarithmic ratio is constructed. The calculation formula is: ,in, .

6. The rock quality factor analysis method based on dual reference samples according to claim 5, characterized in that, Linear fitting is performed on the relationship between the first amplitude logarithmic ratio and frequency, and the relationship between the second amplitude logarithmic ratio and frequency, respectively. Based on the slope parameter obtained from the linear fitting, a two-variable linear equation is constructed, consisting of the slope parameter, the quality factor of the second reference sample, and the quality factor value of the rock sample to be tested. By solving the equation, the quality factor of the second reference sample and the corresponding quality factor value of the rock sample to be tested can be obtained, including: A linear fit is performed on the relationship between the first amplitude logarithmic ratio and the frequency to obtain the first slope. The fitting process is as follows: , , , , Where Q is the quality factor value corresponding to the sample; A linear fit was performed on the relationship between the second amplitude logarithmic ratio and the frequency to obtain the second slope. The fitting process is as follows: , ; Using the first slope and the second slope, the quality factor value corresponding to the rock sample to be tested is calculated. The calculation formula is: ; Using the first slope and the second slope, the calculated quality factor value corresponding to the second reference sample is obtained. The calculation formula is: .

7. The rock quality factor analysis method based on dual reference samples according to claim 6, characterized in that, The calculated quality factor of the second reference sample is compared with the known value to obtain a stable and accurate quality factor for the tested rock sample, including: Determine the quality factor calibration value and the calculated quality factor value of the second reference sample. Is the deviation between them less than or equal to the preset deviation threshold? If the quality factor calibration value of the second reference sample and the calculated quality factor value If the deviation between the two values ​​is less than or equal to a preset deviation threshold, then the quality factor value of the rock sample to be tested is... efficient; If the quality factor calibration value of the second reference sample and the calculated quality factor value If the deviation between the values ​​is greater than a preset deviation threshold, then the quality factor value of the rock sample to be tested will be... invalid.

8. A computer program product, characterized in that, The computer program product includes computer program instructions that, when executed by a processor, implement the steps of a rock quality factor analysis method based on dual reference samples as described in any one of claims 1 to 7.

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