VSP near-surface ringing suppression processing method based on three-dimensional ground seismic driving
By adopting the near-surface shock suppression treatment method driven by three-dimensional ground seismic in VSP technology, and using technologies such as gunpoint statistical deconvolution and multi-channel statistical wavelet deconvolution, the difficulty of VSP in statistics and processing of spatial differences in near-surface excitation wavelets is solved, effectively improving the consistency of near-surface shock suppression and excitation wavelets is achieved, and the closing difference between VSP imaging data and ground seismic imaging data is improved.
Patent Information
- Application Number
- CN202311111208.6
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2023-08-31
- Publication Date
- 2025-02-28
AI Technical Summary
VSP technology has difficulties in statistics and processing of spatial differences between near-surface excitation wavenumbers, which makes it difficult to effectively suppress near-surface shock interference and improve the consistency of excitation wavenumbers, thereby affecting the closure difference between VSP imaging data and ground seismic imaging data.
The VSP near-surface shock suppression treatment method based on three-dimensional ground seismic drive is adopted. By reading the ground seismic pre-stack data and VSP data that have been denoised and compensated, and adding the same static correction amount to reduce the time difference between the data. Then, the deconvolution method and parameter-driven VSP excitation shock shock are used to suppress the sound shock shock shock, and the suppression process of the sound shock shock is used, specifically using the gunpoint statistical deconvolution and multi-channel statistical wavelet deconvolution.
It effectively suppresses the near-surface shock interference of VSP, improves the consistency of excitation wavelets, significantly improves the closure difference between VSP and ground seismic imaging data, and improves the effect of well seismic closure imaging.
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Figure CN119535552A_ABST
Abstract
Description
Technical Field
[0001] The invention belongs to the technical field of oil and gas exploration and development, and in particular relates to a VSP near-surface ringing suppression processing method based on three-dimensional ground seismic drive. Background Art
[0002] In the process of ground seismic technology development, seismic resolution enhancement processing technology has also made great progress based on statistical theory. Among them, Zhang Yonggang (1988) improved the stability of pre-stack deconvolution through a two-step statistical wavelet deconvolution method. Ling Yun proposed a method of surface consistent variable step-size prediction deconvolution and dune rumble suppression based on statistical theory, which makes seismic deconvolution technology more effective and stable based on ground seismic observation methods. The above resolution enhancement methods based on statistical theory have achieved good processing results in onshore seismic data processing.
[0003] Due to the different observation methods of VSP and ground seismic, there are differences in the processing of improving resolution between the two. There are obvious differences in the statistics and processing of spatial difference information of near-surface excited wavelets between VSP and ground seismic. VSP mainly obtains deterministic wavelets through downlink waves. When the well-source distance is non-zero, especially when the well-source distance is large, it is usually difficult to obtain effective seismic wavelets. Summary of the invention
[0004] In order to solve the above-mentioned problems, the present invention proposes: a VSP near-surface ringing suppression processing method based on three-dimensional ground seismic drive, which gives priority to reading ground seismic pre-stack data and VSP data that have been processed by denoising and compensation, and adds the same static correction amount at the same time to reduce the time difference between data and ensure the quality control of the results data. In this process, the headers of the two data are guaranteed to be the same, which is convenient for using the headers for information matching and fusion processing, and the deconvolution method and parameters of ground seismic suppression of ringing are used to drive the suppression processing of VSP-excited ringing, that is, using shot point statistical deconvolution.
[0005] Furthermore, shot point statistical deconvolution improves the imaging resolution of seismic data at the excitation point, eliminates the influence of ghost reflections produced by the excitation point, and performs wavelet shaping in the shot point domain.
[0006] Furthermore, multi-channel statistical wavelet deconvolution is performed on the common shot point gathers to eliminate the influence of the shot points on the wavelet. The statistical wavelet amplitude spectrum is given by the following method:
[0007]
[0008] Perform seismic wavelet estimation on the shot gather, give a prediction step, output the minimum phase wavelet, find the deconvolution of the shot gather in the least squares sense, solve the deconvolution operator, and then use the deconvolution factor to convolve each trace in the gather to complete the statistical wavelet deconvolution of the shot gather.
[0009] Furthermore, a desired output is selected to meet the need of deconvolution, and the minimum phase broadband Ricker wavelet is selected as the desired output.
[0010] Furthermore, a broadband Ricker wavelet is defined as the expected output wavelet. Since the broadband Ricker wavelet is a good approximation of the impulse function, its main lobe is very narrow and the side lobe amplitude is very small. The equivalent frequency of the main lobe is much higher than the peak frequency of the amplitude spectrum, so that the data can obtain a higher resolution. The amplitude spectrum of the broadband Ricker wavelet is relatively narrow, the peak frequency is relatively high, and the steepness of the decline in the high-frequency direction is large, so that the frequency components with a higher signal-to-noise ratio can be well utilized. Under the condition of achieving the same resolution, the broadband Ricker wavelet is more beneficial to the signal-to-noise ratio.
[0011] Furthermore, the wavelet processing is quality controlled and analyzed through autocorrelation and cross-correlation.
[0012] Furthermore, the autocorrelation function is the same for two data, judging the similarity between them at different moments.
[0013]
[0014] The R autocorrelation function is a function of the time difference τ between the two signals. R(τ) refers to the autocorrelation value of the signal when the energy signal f(t) is τ.
[0015] Furthermore, the cross-correlation function is used to determine the similarity between two data points. It is a function of the time difference τ between the two data points. Its formula is
[0016]
[0017]
[0018] The cross-correlation function R is a function of the time difference τ between the two signals. 12 (τ) refers to the cross-correlation value of the energy signal f1(t) compared with the energy signal f2(t) when the lead time is τ. 21 (τ) refers to the cross-correlation value of the energy signal f2(t) compared with the energy signal f1(t) when the lead time is τ. 12 (τ)≠R 21 (τ).
[0019] The beneficial effects of the present invention are as follows: the present invention is very beneficial in that it uses the deconvolution method and parameters of ground seismic suppression to drive the suppression processing of VSP excitation ringing. VSP uses the same processing parameters and calculation methods of ground seismic to suppress the near-surface ringing at the excitation point, which can obtain a better near-surface ringing suppression effect, and at the same time can improve the consistency and wavelet shaping of VSP and ground seismic excitation. From the zero-well source distance VSP track data after near-surface ringing suppression, the multi-phase ringing of VSP direct waves and reflected waves is obviously suppressed. From the statistical correlation comparison, it can be seen that after the near-surface ringing suppression processing, the side lobes of the VSP statistical autocorrelation are effectively suppressed. It is more reasonable to use VSP and three-dimensional ground seismic fusion processing (mutual driving), and at the same time, better well seismic closure imaging processing effect can be obtained. BRIEF DESCRIPTION OF THE DRAWINGS
[0020] Figure 1 is an operation flow chart of the present invention;
[0021] Figure 2 It is a shot point deconvolution flow chart of the present invention;
[0022] Figure 3 A zero-well source distance VSP pure wave data diagram provided by an embodiment of the present invention;
[0023] Figure 4 A zero-well source distance VSP gather data diagram after near-surface ringing suppression provided by an embodiment of the present invention;
[0024] Figure 5 A statistical diagram of the autocorrelation of conventional zero-well source distance VSP processing and the autocorrelation of surface seismic provided in an embodiment of the present invention;
[0025] Figure 6 A statistical diagram of the fusion processing of zero-well source distance VSP autocorrelation and surface seismic autocorrelation provided in an embodiment of the present invention;
[0026] Figure 7 This is a statistical diagram of the cross-correlation analysis of zero-well source distance VSP and surface seismic stacking provided in an embodiment of the present invention. DETAILED DESCRIPTION
[0027] In order to make the technical means and objectives adopted by the present invention easy to understand, the present invention is further described below in conjunction with a specific implementation method. A VSP near-surface ringing suppression processing method based on three-dimensional ground seismic drive gives priority to reading in ground seismic pre-stack data and VSP data that have been processed by denoising and compensation, and at the same time adding the same static correction amount to reduce the time difference between the data and ensure the quality control of the result data. In this process, the headers of the two data are guaranteed to be the same, which is convenient for using the headers for information matching and fusion processing. The deconvolution method and parameters of ground seismic suppression of ringing are used to drive the suppression processing of VSP-excited ringing, that is, shot point statistical deconvolution is used.
[0028] Among them, shot point statistical deconvolution improves the imaging resolution of seismic data at the excitation point, eliminates the influence of ghost reflections produced by the excitation point, and performs wavelet shaping in the shot point domain.
[0029] Among them, multi-channel statistical wavelet deconvolution is performed on the common shot point gather to eliminate the influence of the shot point on the wavelet, and the statistical wavelet amplitude spectrum is given by the following method:
[0030]
[0031] Perform seismic wavelet estimation on the shot gather, give a prediction step, output the minimum phase wavelet, find the deconvolution of the shot gather in the least squares sense, solve the deconvolution operator, and then use the deconvolution factor to convolve each trace in the gather to complete the statistical wavelet deconvolution of the shot gather.
[0032] Among them, a desired output is selected to meet the needs of deconvolution, and the minimum phase broadband Ricker wavelet is selected as the desired output.
[0033] Among them, a broadband Ricker wavelet is defined as the expected output wavelet. Since the broadband Ricker wavelet is a good approximation of the impulse function, its main lobe is very narrow and the side lobe amplitude is very small. The equivalent frequency of the main lobe is much higher than the peak frequency of the amplitude spectrum, so that the data can obtain a higher resolution. The amplitude spectrum of the broadband Ricker wavelet is relatively narrow, the peak frequency is relatively high, and the steepness of the decline in the high-frequency direction is large, so that the frequency components with higher signal-to-noise ratio can be well utilized. Under the condition of achieving the same resolution, the broadband Ricker wavelet is more beneficial to the signal-to-noise ratio.
[0034] Among them, the quality control analysis of wavelet processing is carried out through autocorrelation and cross-correlation.
[0035] Among them, the autocorrelation function is the same as two data, judging the similarity between them at different moments.
[0036]
[0037] The R autocorrelation function is a function of the time difference τ between the two signals. R(τ) refers to the autocorrelation value of the signal when the energy signal f(t) is τ.
[0038] Among them, the cross-correlation function is used to judge the similarity of two data. It is a function of the time difference τ between the two data. Its formula is
[0039]
[0040]
[0041] The cross-correlation function R is a function of the time difference τ between the two signals. 12 (τ) refers to the cross-correlation value of the energy signal f1(t) compared with the energy signal f2(t) when the lead time is τ. 21 (τ) refers to the cross-correlation value of the energy signal f2(t) compared with the energy signal f1(t) when the lead time is τ. 12 (τ)≠R 21 (τ).
[0042] In the zero-well source distance VSP wavelet processing method, the relevant technology is VSP prediction deconvolution.
[0043] There are also significant differences between this method and ground seismic statistical wavelet processing. After analyzing the reasons, the study believes that it is difficult for VSP to accurately obtain the spatial differences of wavelets caused by near-surface excitation, so it is impossible to compensate and eliminate these effects, effectively suppress near-surface ringing interference, and improve the consistency of excited wavelets. This is also an important reason for the closure difference between VSP imaging data and ground seismic imaging data.
[0044] Due to the differences in the above VSP calculation methods and the near-surface excitation wavelets, there are large differences between the frequency, phase and waveform of VSP and ground seismic imaging. How to effectively eliminate the inconsistency of time, amplitude, frequency, phase and waveform caused by the different VSP and ground seismic observation and processing methods is the main problem facing the more extensive and effective application of VSP.
[0045] In order to make the purpose, technical solutions and advantages of the present invention clearer, the technical solutions of the present invention will be clearly and completely described below in conjunction with the drawings in the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all of the embodiments.
[0046] Figure 1 FIG. 1 is one of the flow charts of the VSP and ground seismic fusion processing flow provided by the embodiment of the present invention, such as Figure 1 As shown, the method comprises at least the following steps:
[0047] Step 1: Based on the 3D seismic data processing method of the target block, fusion processing is performed first. Read in the ground seismic prestack data and VSP data that have been processed by denoising and compensation. In this process, the headers of the two data are guaranteed to be the same, which is convenient for matching the header information.
[0048] Specifically, the ground seismic data is fused with the VSP data and then time-frequency compensation is performed. This study uses the "spherical divergence and absorption attenuation compensation in the time-frequency space domain" technology to achieve compensation for near-surface and earth absorption attenuation. This technology effectively compensates for the energy and frequency attenuation caused by near-surface and earth absorption attenuation through time-frequency decomposition and reconstruction, fitting of absorption attenuation curves and model shot processing technology, and eliminates spatial excitation energy and frequency differences.
[0049] Step 2: Add the same static correction value at the same time to reduce the time difference between data and ensure the quality control of the results data.
[0050] Specifically, in order to eliminate the spatial differences in near-surface excitation time, excitation amplitude, frequency, phase and wavelet, and to achieve the best possible closure imaging of time, amplitude, frequency, phase and wavelet between VSP and ground seismic imaging, the excitation static correction in the VSP and ground seismic fusion processing flow is processed by ground seismic driven VSP.
[0051] Step 3: Perform shot point statistical deconvolution processing on the fused data of surface seismic data and VSP data.
[0052] Specifically, first, we need to select a desired output. In order to meet the needs of deconvolution, we select the minimum phase broadband Ricker wavelet as the desired output. The broadband Ricker wavelet is defined as the desired output wavelet because it is a good approximation of the impulse function. Its main lobe is very narrow and its side lobe amplitude is very small. The equivalent frequency of the main lobe is much higher than the peak frequency of the amplitude spectrum, so that the data can obtain a higher resolution. In addition, the amplitude spectrum of the broadband Ricker wavelet is relatively narrow, the peak frequency is relatively high, and the steepness of the decline in the high-frequency direction is large, so that the frequency components with higher signal-to-noise ratio can be well utilized. Under the condition of achieving the same resolution, the broadband Ricker wavelet is more beneficial to the signal-to-noise ratio. Figure 2 This is the shot point statistical deconvolution process.
[0053] The signal-to-noise ratio of VSP seismic data is improved by shot point statistical deconvolution, wavelet consistency is enhanced, ringing is suppressed and wavelet shaping is performed. Figure 3 and Figure 4 ) It can be seen from the comparison of the number of gathers that the multi-phase ringing of the VSP direct wave and reflected wave is obviously suppressed.
[0054] Step 4: Perform autocorrelation and cross-correlation processing on the surface seismic data and VSP data after shot point statistical deconvolution processing.
[0055] Figure 5 and Figure 6 The statistical autocorrelation results of VSP common detection points after near-surface ringing shock suppression are given. Figure 5 and Figure 6 Comparison of the statistical correlations of the left and right figures shows that after the near-surface ringing suppression process, the sidelobes of the VSP statistical autocorrelation have been effectively suppressed. The two data wavelets are more consistent, which is helpful for comparative calibration. Figure 7 The cross-correlation results of VSP after near-surface ringing suppression are given. It can be seen that except for a few traces with large interference, the correlation time difference between the two data is basically zero, indicating that after the shot point statistical deconvolution processing, the closure difference between the VSP imaging data and the ground seismic imaging data has been effectively eliminated.
[0056] Through the description of the above implementation methods, those skilled in the art can clearly understand that each implementation method can be implemented by means of software plus a necessary general hardware platform. Based on this understanding, the above technical solution can be essentially or the part that contributes to the relevant technology can be embodied in the form of a software product, which can be stored in a computer-readable storage medium, such as ROM / RAM, a disk, an optical disk, etc., including a number of instructions for a computer device (which can be a personal computer, a server, or a network device, etc.) to execute the methods described in each embodiment or some parts of the embodiment.
[0057] The purpose of the present invention is to use the deconvolution method and parameters of ground earthquake suppression to drive the suppression processing of VSP excitation ringing. After the actual VSP drives the ground seismic processing, it is difficult for VSP to achieve effective closure of time, frequency, phase and waveform with the three-dimensional ground seismic processing results. Because it is difficult for VSP to obtain the spatial difference information of the excited ringing and the excited wavelet caused by the lateral change of the near-surface structure, it is impossible to effectively suppress the near-surface ringing interference and it is difficult to improve the consistency of the excited wavelet. Ground earthquakes usually use the excitation point statistical prediction deconvolution to suppress near-surface ringing. Through the statistics of large-area excitation points and reception, relatively good seismic wavelets can be obtained, thereby obtaining a better seismic wavelet consistency processing effect.
[0058] The above description is only a preferred specific implementation manner of the present invention, but the protection scope of the present invention is not limited thereto. Any technician familiar with the technical field can make equivalent replacements or changes according to the technical solutions and concepts of the present invention within the technical scope disclosed by the present invention, which should be covered by the protection scope of the present invention.
Claims
1. A VSP near-surface ringing suppression method based on three-dimensional ground seismic drive, characterized in that: Priority is given to reading in the ground seismic prestack data and VSP data that have been processed with denoising and compensation, and the same static correction is added to reduce the time difference between the data and ensure the quality control of the results data. In this process, the headers of the two data are kept the same, which is convenient for using the headers for information matching and fusion processing. The deconvolution method and parameters of ground seismic suppression of ringing are used to drive the suppression processing of VSP-excited ringing, that is, shot point statistical deconvolution is used.
2. The VSP near-surface ringing suppression processing method based on three-dimensional ground seismic drive according to claim 1 is characterized in that: Shot point statistical deconvolution improves the imaging resolution of seismic data at the excitation point, eliminates the influence of ghost reflections produced by the excitation point, and performs wavelet shaping in the shot point domain.
3. The VSP near-surface ringing suppression processing method based on three-dimensional ground seismic drive according to claim 2 is characterized in that: Perform multi-channel statistical wavelet deconvolution on the common shot point gather to eliminate the influence of the shot point on the wavelet. The statistical wavelet amplitude spectrum is given by the following method: Perform seismic wavelet estimation on the shot gather, give a prediction step, output the minimum phase wavelet, find the deconvolution of the shot gather in the least squares sense, solve the deconvolution operator, and then use the deconvolution factor to convolve each trace in the gather to complete the statistical wavelet deconvolution of the shot gather.
4. The VSP near-surface ringing suppression processing method based on three-dimensional ground seismic drive according to claim 3 is characterized in that: Select a desired output to meet the needs of deconvolution, and select the minimum phase broadband Ricker wavelet as the desired output.
5. The VSP near-surface ringing suppression processing method based on three-dimensional ground seismic drive according to claim 4 is characterized in that: Define broadband Ricker wavelet as the expected output wavelet. Since broadband Ricker wavelet is a good approximation of the impulse function, its main lobe is very narrow and the side lobe amplitude is very small. The equivalent frequency of the main lobe is much higher than the peak frequency of the amplitude spectrum, so that the data can obtain a higher resolution. The amplitude spectrum of broadband Ricker wavelet is relatively narrow, the peak frequency is relatively high, and the steepness of the decline in the high-frequency direction is large, so that the frequency components with higher signal-to-noise ratio can be well utilized. Under the condition of achieving the same resolution, broadband Ricker wavelet is more beneficial to the signal-to-noise ratio.
6. The VSP near-surface ringing suppression processing method based on three-dimensional ground seismic drive according to claim 5, characterized in that: Secondly, the quality control analysis of wavelet processing is carried out through autocorrelation and cross-correlation.
7. The VSP near-surface ringing suppression processing method based on three-dimensional ground seismic drive according to claim 6 is characterized in that: The autocorrelation function is used to determine the similarity between two data points at different moments. The R autocorrelation function is a function of the time difference τ between the two signals. R(τ) refers to the autocorrelation value of the signal when the energy signal f(t) is τ.
8. The VSP near-surface ringing suppression processing method based on three-dimensional ground seismic drive according to claim 7 is characterized in that: The cross-correlation function is used to determine the similarity between two data points. It is a function of the time difference τ between the two data points. Its formula is The cross-correlation function R is a function of the time difference τ between the two signals. 12 (τ) refers to the cross-correlation value of the energy signal f1(t) compared with the energy signal f2(t) when the lead time is τ. 21 (τ) refers to the cross-correlation value of the energy signal f2(t) compared with the energy signal f1(t) when the lead time is τ. 12 (τ)≠R 21 (τ).