Amplitude preservation interlayer multiple prediction method and device

Abstract

The invention relates to the field of geophysical exploration, and particularly discloses an amplitude-preserved interlayer multiple prediction method and device, and the method comprises the steps: carrying out the background medium velocity migration of seismic data, and obtaining pseudo-depth domain data; specifying the generation horizon depth of interlayer multiples, and calculating according to a speed model or logging information to obtain an amplitude correction factor; substituting the pseudo depth domain data and the amplitude correction factor into an inverse scattering series method formula to carry out interlayer multiple prediction; and subtracting the predicted interlayer multiples from the seismic data to obtain a result after interlayer multiple suppression. According to the amplitude-preserving interlayer multiple wave prediction method provided by the invention, the amplitude correction factor is introduced to improve the interlayer multiple wave prediction method so as to improve the accuracy of interlayer multiple wave amplitude prediction, and a test processing result shows that the method can predict accurate travel time and amplitude of interlayer multiple waves and provides guarantee for effective suppression of the multiple waves.

Description

Technical Field

[0001] The invention relates to the field of geophysical exploration, and in particular to an amplitude-preserving interlayer multiple wave prediction method and device. Background Art

[0002] In seismic exploration, due to the existence of underground strong reflection interfaces, seismic waves are reflected multiple times between strong reflection interfaces to form interlayer multiple waves. The interlayer multiple waves and the primary reflection waves are superimposed and interfered with each other, which seriously reduced the resolution of seismic data, increased the difficulty of identifying effective waves, and affected the quality of seismic imaging and the authenticity and reliability of seismic interpretation. Therefore, attenuating or eliminating interlayer multiple waves is an important link in seismic data processing. In order to eliminate the interference of interlayer multiple waves and improve data resolution, the geophysical exploration community has proposed two types of multiple wave suppression methods: one is a filtering method based on the characteristic difference between the primary wave and the multiple waves; the other is a predictive subtraction method based on wave theory. The filtering method includes predictive deconvolution method, fk filtering method, Radon transform method, etc. When the assumption conditions are well met, the filtering method can effectively attenuate or eliminate multiple waves, and the calculation amount is small, easy to implement, and efficient. However, the filtering method requires more underground assumption information. When the characteristic difference between the primary wave and the multiple waves is small or non-existent, it is difficult to obtain the ideal effect, and even the primary wave will be seriously damaged. The prediction subtraction method avoids the limitations of the filtering method and does not require prior information. It is the main development trend of the multiple wave suppression method. It mainly includes the feedback iteration method and the inverse scattering series method. For the suppression of interlayer multiple waves, the feedback iteration method requires a certain amount of manual intervention. It predicts the interlayer multiple waves by specifying the multiple wave generation layer layer by layer, while the inverse scattering series method is completely data-driven and does not require manual intervention. It predicts through the algorithm itself and can predict all interlayer multiple waves at once. It is currently the most advanced interlayer multiple wave suppression method. The current inverse scattering series method can predict the accurate travel time of interlayer multiple waves, but it cannot predict the accurate amplitude.

[0003] Based on this technical background, the present invention studies an amplitude-preserving interlayer multiple wave prediction method and device. Summary of the invention

[0004] In view of the shortcomings of the prior art, the present invention provides an amplitude-preserving interlayer multiple wave prediction method and device. The method improves the interlayer multiple wave prediction method by introducing an amplitude correction factor to improve the accuracy of the interlayer multiple wave amplitude prediction. Test processing results show that the method can predict the accurate travel time and amplitude of the interlayer multiple waves, providing a guarantee for the effective suppression of the multiple waves.

[0005] In order to achieve the above object, a first aspect of the present invention provides an amplitude-preserving interlayer multiple wave prediction method, comprising:

[0006] Perform background medium velocity migration on seismic data to obtain pseudo depth domain data;

[0007] Specify the depth of the interlayer multiple wave generation layer, and calculate the amplitude correction factor from the velocity model or logging data;

[0008] Substituting the pseudo-depth domain data and the amplitude correction factor into the inverse scattering series method formula to predict interlayer multiple waves;

[0009] The predicted interlayer multiple waves are subtracted from the seismic data to obtain a result after the interlayer multiple waves are suppressed.

[0010] A second aspect of the present invention provides an amplitude-preserving interlayer multiple wave prediction device, comprising:

[0011] An offset module is used to perform background medium velocity offset on seismic data to obtain pseudo depth domain data;

[0012] The correction factor calculation module is used to specify the depth of the interlayer multiple wave generation layer and calculate the amplitude correction factor from the velocity model or logging data;

[0013] A prediction module, used for substituting the pseudo-depth domain data and the amplitude correction factor into the inverse scattering series method formula to perform interlayer multiple wave prediction;

[0014] The subtraction module is used to subtract the predicted interlayer multiple waves from the seismic data to obtain the result after the interlayer multiple waves are suppressed.

[0015] A third aspect of the present invention provides an electronic device, the electronic device comprising:

[0016] A memory storing executable instructions;

[0017] A processor is used to execute the executable instructions in the memory to implement the amplitude-preserving inter-layer multiple wave prediction method described in the first aspect.

[0018] A fourth aspect of the present invention provides a computer-readable storage medium storing a computer program, which, when executed by a processor, implements the amplitude-preserving interlayer multiple wave prediction method described in the first aspect.

[0019] The beneficial effects of the present invention include:

[0020] (1) The amplitude-preserving interlayer multiple wave prediction method proposed in the present invention improves the interlayer multiple wave prediction method by introducing an amplitude correction factor to improve the accuracy of the interlayer multiple wave amplitude prediction. The test processing results show that this method can predict the accurate travel time and amplitude of the interlayer multiple waves, providing a guarantee for the effective suppression of the multiple waves.

[0021] (2) The amplitude-preserving interlayer multiple wave prediction method proposed in the present invention substitutes the pseudo-depth domain data and the amplitude correction factor into the inverse scattering series method formula to predict the interlayer multiple waves. It not only has a rigorous theoretical basis, but also avoids the problem of inaccurate amplitude prediction of the interlayer multiple waves by the inverse scattering series method itself, and has strong practicality.

[0022] (3) The amplitude-preserving interlayer multiple wave prediction method proposed in the present invention is completely data-driven and does not require human intervention. It performs predictions through the algorithm itself, has a small amount of calculation, is easy to implement, and has high efficiency.

[0023] Other features and advantages of the present invention will be described in detail in the following detailed description. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] The above and other objects, features and advantages of the present invention will become more apparent through a more detailed description of exemplary embodiments of the present invention with reference to the accompanying drawings.

[0025] Figure 1 The figure is a flow chart of the amplitude-preserving interlayer multiple wave prediction method proposed in the present invention.

[0026] Figure 2 The figure is a flow chart of a specific implementation of the amplitude-preserving interlayer multiple wave prediction method proposed by the present invention.

[0027] Figure 3 This is a schematic diagram comparing the simulation data, the conventional method and the interlayer multiple wave prediction results of the method of the present invention in a specific implementation manner of the amplitude-preserving interlayer multiple wave prediction method proposed by the present invention. DETAILED DESCRIPTION

[0028] The preferred embodiments of the present invention will be described in more detail below. Although the preferred embodiments of the present invention are described below, it should be understood that the present invention can be implemented in various forms and should not be limited to the embodiments set forth herein.

[0029] The present invention provides an amplitude-preserving interlayer multiple wave prediction method, such as Figure 1 ,include:

[0030] Perform background medium velocity migration on seismic data to obtain pseudo depth domain data;

[0031] Specify the depth of the interlayer multiple wave generation layer, and calculate the amplitude correction factor from the velocity model or logging data;

[0032] Substitute pseudo-depth domain data and amplitude correction factors into the inverse scattering series method formula to predict interlayer multiple waves;

[0033] The predicted interlayer multiple waves are subtracted from the seismic data to obtain the result after the interlayer multiple waves are suppressed.

[0034] In the present invention, the amplitude correction factor is introduced to improve the interlayer multiple wave prediction method to improve the accuracy of the interlayer multiple wave amplitude prediction. The test processing results show that this method can predict the accurate travel time and amplitude of the interlayer multiple waves, providing a guarantee for the effective suppression of the multiple waves.

[0035] According to the present invention, performing background medium velocity migration on pre-processed seismic data to obtain pseudo depth domain data includes:

[0036] The original seismic data is processed to obtain a preliminary velocity model, and the preliminary velocity model is subjected to background medium velocity migration to obtain pseudo depth domain data.

[0037] According to the present invention, the calculation formula of the amplitude correction factor is:

[0038]

[0039] Among them, R i is the reflection coefficient of the i-th downlink reflection layer, z is the depth of the interlayer multiple wave generation layer, F j (z) is the correction factor.

[0040] Preferably, the inverse scattering series method formula is:

[0041]

[0042] Where k is the vertical wave number, z j is the pseudo depth of background medium velocity domain imaging, and the value of j is 1, 2 or 3.

[0043] According to the present invention, b 1 The expression of (z) is:

[0044]

[0045] The expression of k is:

[0046] k=2ω / c 0 ;

[0047] Among them, c 0 is the background medium speed.

[0048] According to the present invention, the formula of the inverse scattering series method after substituting the pseudo depth domain data and the amplitude correction factor is:

[0049]

[0050] In the present invention, pseudo-depth domain data and amplitude correction factors are substituted into the inverse scattering series method formula to predict interlayer multiple waves. This not only has a rigorous theoretical basis, but also avoids the problem of inaccurate amplitude prediction of interlayer multiple waves by the inverse scattering series method itself, and has strong practicality.

[0051] Preferably, the method used to subtract the predicted interlayer multiples from the original seismic data is an adaptive subtraction method.

[0052] The method of the present invention is completely data-driven, does not require human intervention, performs predictions through the algorithm itself, has a small amount of calculation, is easy to implement, and has high efficiency.

[0053] The present invention will be described in more detail below by way of examples.

[0054] Embodiment 1:

[0055] like Figure 2 As shown, this embodiment provides an amplitude-preserving interlayer multiple wave prediction method, which first preprocesses seismic data and obtains a preliminary velocity model, then performs background medium velocity migration on the preprocessed data to obtain pseudo-depth domain data, then specifies the generation layer depth of the interlayer multiple waves, calculates the amplitude correction factor that varies with depth according to the velocity model, and finally substitutes it into the improved inverse scattering series interlayer multiple wave method to predict the interlayer multiple waves; the specific implementation steps of the method are:

[0056] Step 1: Perform background medium velocity migration on the preprocessed seismic data to obtain pseudo depth domain data;

[0057] Step 2: Specify the depth of the interlayer multiple wave generation layer, and calculate the amplitude correction factor that varies with depth based on the velocity model;

[0058] Step 3: Substitute the pseudo-depth domain data and the amplitude correction factor into the inverse scattering series method (Formula 3) to predict interlayer multiple waves;

[0059] Step 4: Subtract the predicted interlayer multiple waves from the original seismic data through the adaptive subtraction method to obtain the result after the interlayer multiple waves are suppressed.

[0060] The simulation data in this example were generated by a simple layered model with three reflecting interfaces; Figure 3 (a) is the simulation data, which contains three primary waves and the first-order and second-order inter-order multiple waves generated by them; in order to better verify the effect of this method, the Figure 3 (a) Only look at the data in the dark box; Figure 3 (b) is the result predicted by the conventional inverse scattering series method, where the light color is the input data and the dark color is the predicted result. It can be seen that the time predicted by the conventional method is accurate, but the amplitude is different from the simulated data; Figure 3 (c) The dark color in the middle is the interlayer multiple waves predicted by the method of the present invention; it can be seen that the method of the present invention can predict the accurate time and amplitude of the interlayer multiple waves. It can be seen that the improved inverse scattering series method of the present invention can effectively improve the accuracy of the prediction of interlayer multiple waves through model data testing, and provide a guarantee for the suppression of multiple waves.

[0061] Embodiment 2:

[0062] This embodiment provides an amplitude-preserving interlayer multiple wave prediction method, such as Figure 1 As shown, including:

[0063] Perform background medium velocity migration on seismic data to obtain pseudo depth domain data;

[0064] Specify the depth of the interlayer multiple wave generation layer, and calculate the amplitude correction factor from the velocity model or logging data;

[0065] Substitute pseudo-depth domain data and amplitude correction factors into the inverse scattering series method formula to predict interlayer multiple waves;

[0066] Subtract the predicted interlayer multiple waves from the seismic data to obtain the result after the interlayer multiple waves are suppressed;

[0067] The pseudo depth domain data obtained by background medium velocity migration of pre-processed seismic data include:

[0068] The original seismic data is subjected to a preliminary velocity model, and the preliminary velocity model is subjected to background medium velocity migration to obtain pseudo depth domain data;

[0069] The calculation formula of the amplitude correction factor is:

[0070]

[0071] Where Ri is the reflection coefficient of the i-th downgoing reflection layer, z is the depth of the interlayer multiple wave generation layer, F j (z) is the correction factor;

[0072] The formula of the inverse scattering series method is:

[0073]

[0074] Where k is the vertical wave number, z j is the pseudo depth of background medium velocity domain imaging, and the value of j is 1, 2 or 3;

[0075] b 1 The expression of (z) is:

[0076]

[0077] The expression of k is:

[0078] k=2ω / c 0 ;

[0079] Among them, c 0 is the background medium speed;

[0080] The formula of the inverse scattering series method after substituting the pseudo-depth domain data and the amplitude correction factor is:

[0081]

[0082] The method used to subtract the predicted interlayer multiple waves from the original seismic data is the adaptive subtraction method.

[0083] Embodiment three:

[0084] This embodiment provides an amplitude-preserving interlayer multiple wave prediction device, including:

[0085] An offset module is used to perform background medium velocity offset on seismic data to obtain pseudo depth domain data;

[0086] The correction factor calculation module is used to specify the depth of the interlayer multiple wave generation layer and calculate the amplitude correction factor from the velocity model or logging data;

[0087] A prediction module, used to substitute pseudo-depth domain data and amplitude correction factors into the inverse scattering series method formula to predict interlayer multiple waves;

[0088] A subtraction module is used to subtract the predicted interlayer multiple waves from the seismic data to obtain the result after the interlayer multiple waves are suppressed;

[0089] The pseudo depth domain data obtained by background medium velocity migration of pre-processed seismic data include:

[0090] The original seismic data is subjected to a preliminary velocity model, and the preliminary velocity model is subjected to background medium velocity migration to obtain pseudo depth domain data;

[0091] The calculation formula of the amplitude correction factor is:

[0092]

[0093] Among them, R i is the reflection coefficient of the i-th downlink reflection layer, z is the depth of the interlayer multiple wave generation layer, F j (z) is the correction factor;

[0094] The formula of the inverse scattering series method is:

[0095]

[0096] Where k is the vertical wave number, z j is the pseudo depth of background medium velocity domain imaging, and the value of j is 1, 2 or 3;

[0097] b 1 The expression of (z) is:

[0098]

[0099] The expression of k is:

[0100] k=2ω / c 0 ;

[0101] Among them, c 0 is the background medium speed;

[0102] The formula of the inverse scattering series method after substituting the pseudo-depth domain data and the amplitude correction factor is:

[0103]

[0104] The method used to subtract the predicted interlayer multiples from the original seismic data is adaptive subtraction.

[0105] Embodiment 4:

[0106] An embodiment of the present invention provides an electronic device including a memory and a processor.

[0107] A memory storing executable instructions;

[0108] The processor runs the executable instructions in the memory to implement the amplitude-preserving inter-layer multiple wave prediction method.

[0109] The memory is used to store non-temporary computer-readable instructions. Specifically, the memory may include one or more computer program products, which may include various forms of computer-readable storage media, such as volatile memory and / or non-volatile memory. The volatile memory may, for example, include random access memory (RAM) and / or cache memory (cache), etc. The non-volatile memory may, for example, include read-only memory (ROM), hard disk, flash memory, etc.

[0110] The processor may be a central processing unit (CPU) or other forms of processing units with data processing capabilities and / or instruction execution capabilities, and may control other components in the electronic device to perform desired functions. In one embodiment of the present invention, the processor is used to run the computer-readable instructions stored in the memory.

[0111] Those skilled in the art should be able to understand that in order to solve the technical problem of how to obtain a good user experience, the present embodiment may also include well-known structures such as a communication bus and an interface, and these well-known structures should also be included in the protection scope of the present invention.

[0112] For detailed description of this embodiment, reference may be made to the corresponding descriptions in the aforementioned embodiments, which will not be repeated here.

[0113] Embodiment five:

[0114] An embodiment of the present invention provides a computer-readable storage medium, wherein the computer-readable storage medium stores a computer program, and when the computer program is executed by a processor, an amplitude-preserving inter-layer multiple wave prediction method is implemented.

[0115] The computer-readable storage medium according to the embodiment of the present invention stores non-transitory computer-readable instructions, and when the non-transitory computer-readable instructions are executed by a processor, all or part of the steps of the above-mentioned methods of the embodiments of the present invention are executed.

[0116] The above-mentioned computer-readable storage media include, but are not limited to: optical storage media (e.g., CD-ROM and DVD), magneto-optical storage media (e.g., MO), magnetic storage media (e.g., magnetic tape or mobile hard disk), media with built-in rewritable non-volatile memory (e.g., memory card) and media with built-in ROM (e.g., ROM box).

[0117] The amplitude-preserving interlayer multiple wave prediction method proposed in the embodiment of the present invention uses omnidirectional OVT domain gathers or angle domain ES360 gathers to carry out pre-stack AVAZ direct inversion, does not need to perform azimuth stacking processing on the gathers, and performs ellipse fitting on the inversion results to obtain the fracture development density and fracture azimuth, thereby improving the fracture prediction accuracy.

[0118] The embodiments of the present invention have been described above, and the above description is exemplary, not exhaustive, and is not limited to the disclosed embodiments. Many modifications and changes will be apparent to those skilled in the art without departing from the scope and spirit of the described embodiments.

Claims

1. A method for predicting multiple waves between layers with amplitude preservation. It is characterized in that include: Perform background medium velocity migration on seismic data to obtain pseudo depth domain data; Specify the depth of the interlayer multiple wave generation layer, and calculate the amplitude correction factor from the velocity model or logging data; Substituting the pseudo-depth domain data and the amplitude correction factor into the inverse scattering series method formula to predict interlayer multiple waves; The predicted interlayer multiple waves are subtracted from the seismic data to obtain a result after the interlayer multiple waves are suppressed.

2. The method according to claim 1, It is characterized in that The pseudo depth domain data obtained by background medium velocity migration of pre-processed seismic data include: A preliminary velocity model is obtained from the original seismic data, and background medium velocity migration is performed on the preliminary velocity model to obtain pseudo depth domain data.

3. The method according to claim 2, It is characterized in that The calculation formula of the amplitude correction factor is: Among them, R i is the reflection coefficient of the i-th downlink reflection layer, z is the depth of the interlayer multiple wave generation layer, F j (z) is the correction factor.

4. The method according to claim 3, It is characterized in that The inverse scattering series method formula is: Where k is the vertical wave number, z j is the pseudo depth of background medium velocity domain imaging, and the value of j is 1, 2 or 3.

5. The method according to claim 4, It is characterized in that b 1 The expression of (z) is: The expression of k is: k=2ω / c 0 ; Among them, c 0 is the background medium speed.

6. The method according to claim 5, It is characterized in that The formula of the inverse scattering series method after substituting the pseudo depth domain data and the amplitude correction factor is:

7. The method according to claim 5, It is characterized in that The method used to subtract the predicted interlayer multiple waves from the original seismic data is the adaptive subtraction method.

8. An amplitude-preserving interlayer multiple wave prediction device, It is characterized in that include: An offset module is used to perform background medium velocity offset on seismic data to obtain pseudo depth domain data; The correction factor calculation module is used to specify the depth of the interlayer multiple wave generation layer and calculate the amplitude correction factor from the velocity model or logging data; A prediction module, used for substituting the pseudo-depth domain data and the amplitude correction factor into the inverse scattering series method formula to perform interlayer multiple wave prediction; The subtraction module is used to subtract the predicted interlayer multiple waves from the seismic data to obtain the result after the interlayer multiple waves are suppressed.

9. An electronic device, It is characterized in that The electronic device comprises: A memory storing executable instructions; A processor, wherein the processor runs the executable instructions in the memory to implement the amplitude-preserving inter-layer multiple wave prediction method according to any one of claims 1-7.

10. A computer-readable storage medium, It is characterized in that The computer-readable storage medium stores a computer program, and when the computer program is executed by a processor, the amplitude-preserving interlayer multiple wave prediction method according to any one of claims 1 to 7 is implemented.

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