Method and device for extracting high-fidelity three-dimensional diffracted wave signal, electronic equipment and storage medium

Abstract

The invention provides a high-fidelity three-dimensional diffracted wave signal extraction method and device, electronic equipment and a storage medium, and belongs to the technical field of seismic wave field separation of seismic exploration, in the method, in post-stack seismic data after offset, three-dimensional reflected waves keep linear features, and three-dimensional diffracted waves are converged to a focus point, so that the three-dimensional diffracted wave signals are extracted, and therefore, the high-fidelity three-dimensional diffracted wave signal extraction efficiency is improved. The method comprises the following steps: calculating a local dip angle in the offset post-stack seismic data to obtain the local dip angle of the offset post-stack seismic data which is the accurate local dip angle of a three-dimensional reflected wave, and then converting the local dip angle of the offset post-stack seismic data into the local dip angle of the post-stack seismic data, so that the accuracy of the offset post-stack seismic data is improved. After the post-stack seismic data is subjected to mean filtering based on the accurate local dip angle of the post-stack seismic data, the obtained three-dimensional reflected wave is good in accuracy and high in quality, and finally, the three-dimensional diffracted wave calculated according to the post-stack seismic data and the high-quality three-dimensional reflected wave is good in quality and free of damage.

Description

Technical Field

[0001] The present invention relates to the technical field of seismic wavefield separation in seismic exploration, and in particular, to a method, device, electronic device, and storage medium for extracting high-fidelity three-dimensional diffracted wave signals. Background Art

[0002] During the propagation of seismic waves underground, when encountering a formation interface, reflection waves will be generated to form reflected waves, and the reflected waves can accurately reflect continuous interface information. Geological discontinuities with relatively small scales do not have continuous reflection interfaces and do not generate reflected waves, but act as secondary seismic sources to form diffracted waves. Therefore, seismic diffracted waves are the seismic responses of small-scale geological discontinuities, carrying rich information of small-scale geological bodies and having the potential and important research value for high-resolution exploration.

[0003] However, affected by geometric spreading attenuation, the energy of diffracted waves is one to two orders of magnitude lower than that of reflected waves and will be shielded by strong reflected wave signals, making it impossible to exert its high-resolution detection potential. Therefore, it is necessary to separate the diffracted waves, eliminate the shielding effect of reflected waves, and achieve high-resolution detection of diffracted waves.

[0004] In the existing method for extracting three-dimensional diffracted waves based on dip, dip is directly constructed in pre-stack migration data, such as directly in post-stack seismic data (where post-stack seismic data is one type of pre-stack migration data). Since the end point part of the diffracted wave also has local linear characteristics, its dip often aliases with the dip of the reflected wave, resulting in damage to the energy of the diffracted wave during the later separation process.

[0005] In summary, how to extract high-fidelity three-dimensional diffracted wave signals has become an urgent technical problem to be solved currently. Summary of the Invention

[0006] In view of this, the purpose of the present invention is to provide a method, device, electronic device, and storage medium for extracting high-fidelity three-dimensional diffracted wave signals to alleviate the technical problems of poor quality and damage of the three-dimensional diffracted wave signals extracted by the existing technology.

[0007] In a first aspect, an embodiment of the present invention provides a method for extracting high-fidelity three-dimensional diffracted wave signals, including: Obtaining post-stack seismic data and migration velocity, where the post-stack seismic data includes: three-dimensional reflected waves and three-dimensional diffracted waves; Performing migration on the post-stack seismic data using the migration velocity to obtain the migrated post-stack seismic data, where in the migrated post-stack seismic data, the three-dimensional reflected waves maintain linear characteristics, and the three-dimensional diffracted waves converge to a focal point; Calculating the local dip of the migrated post-stack seismic data, where the local dip of the migrated post-stack seismic data is the local dip of the three-dimensional reflected waves; Calculate the local dip angle of the post-stack seismic data based on the local dip angle of the offset post-stack seismic data; Perform mean filtering on the post-stack seismic data according to the local dip angle of the post-stack seismic data to obtain the three-dimensional reflected wave, and then calculate the three-dimensional diffracted wave based on the post-stack seismic data and the three-dimensional reflected wave.

[0008] Furthermore, performing migration on the post-stack seismic data using the migration velocity includes: Calculating the formula according to the offset post-stack seismic data Calculate the offset post-stack seismic data, where represents the offset post-stack seismic data, represents the post-stack seismic data, represents the Dirac function, represents the abscissa before migration, represents the ordinate before migration, represents the recording time, represents the migration velocity, represents the abscissa after migration, represents the ordinate after migration, represents the time after migration.

[0009] Furthermore, calculating the local dip angle of the offset post-stack seismic data includes: Calculating the formula for the local dip angle of the X plane Calculate the local dip angle of the X plane of the offset post-stack seismic data, where represents the local dip angle of the X plane of the offset post-stack seismic data, represents the offset post-stack seismic data, represents the abscissa after migration, represents the time after migration; Calculating the formula for the local dip angle of the Y plane Calculate the local dip angle of the Y plane of the offset post-stack seismic data, where represents the local dip angle of the Y plane of the offset post-stack seismic data, represents the offset post-stack seismic data, represents the ordinate after migration, represents the time after migration; Take the local dip angle of the X plane of the offset post-stack seismic data and the local dip angle of the Y plane of the offset post-stack seismic data as the local dip angle of the offset post-stack seismic data.

[0010] Further, calculating the local dip angle of the post-stack seismic data based on the local dip angle of the offset post-stack seismic data includes: Calculating the local dip angle of the X plane of the post-stack seismic data according to the local dip angle conversion formula of the X plane wherein, represents the local dip angle of the X plane of the post-stack seismic data, represents the local dip angle of the X plane of the offset post-stack seismic data, represents the local dip angle of the Y plane of the offset post-stack seismic data, represents the offset velocity, , , ; Calculating the local dip angle of the Y plane of the post-stack seismic data according to the local dip angle conversion formula of the Y plane wherein, represents the local dip angle of the Y plane of the post-stack seismic data, represents the local dip angle of the X plane of the offset post-stack seismic data, represents the local dip angle of the Y plane of the offset post-stack seismic data, represents the offset velocity; Taking the local dip angle of the X plane of the post-stack seismic data and the local dip angle of the Y plane of the post-stack seismic data as the local dip angle of the post-stack seismic data.

[0011] Further, performing mean filtering on the post-stack seismic data according to the local dip angle of the post-stack seismic data includes: Performing mean filtering on the post-stack seismic data along the X direction according to the local dip angle of the X plane of the post-stack seismic data to obtain the seismic data after mean filtering along the X direction; Performing mean filtering on the seismic data after mean filtering along the X direction along the Y direction according to the local dip angle of the X plane of the post-stack seismic data to obtain the three-dimensional reflected wave.

[0012] Further, calculating the three-dimensional diffracted wave according to the post-stack seismic data and the three-dimensional reflected wave includes: Calculating the three-dimensional diffracted wave according to the three-dimensional diffracted wave calculation formula wherein, represents the three-dimensional diffracted wave, represents the post-stack seismic data, represents the three-dimensional reflected wave.

[0013] In a second aspect, an apparatus for extracting a high-fidelity three-dimensional diffracted wave signal according to an embodiment of the present invention further includes: An acquisition unit for acquiring post-stack seismic data and migration velocity, wherein the post-stack seismic data includes: three-dimensional reflected waves and three-dimensional diffracted waves; A migration unit for migrating the post-stack seismic data using the migration velocity to obtain the migrated post-stack seismic data, wherein in the migrated post-stack seismic data, the three-dimensional reflected waves maintain a linear feature and the three-dimensional diffracted waves converge to a focal point; A first calculation unit for calculating the local dip of the migrated post-stack seismic data, wherein the local dip of the migrated post-stack seismic data is the local dip of the three-dimensional reflected waves; A second calculation unit for calculating the local dip of the post-stack seismic data based on the local dip of the migrated post-stack seismic data; An average filtering unit for performing average filtering on the post-stack seismic data according to the local dip of the post-stack seismic data to obtain the three-dimensional reflected waves, and then calculating the three-dimensional diffracted waves based on the post-stack seismic data and the three-dimensional reflected waves.

[0014] Further, the migration unit is further configured to: Calculate the formula according to the migrated post-stack seismic data Calculate the migrated post-stack seismic data, where Represents the migrated post-stack seismic data, Represents the post-stack seismic data, Represents the Dirac function, Represents the abscissa before migration, Represents the ordinate before migration, Represents the recording time, Represents the migration velocity, Represents the abscissa after migration, Represents the ordinate after migration, Represents the time after migration.

[0015] In a third aspect, an embodiment of the present invention further provides an electronic device, including a memory, a processor, and a computer program stored on the memory and executable on the processor, wherein when the processor executes the computer program, the steps of the method according to any one of the first aspects are implemented.

[0016] In a fourth aspect, an embodiment of the present invention further provides a computer-readable storage medium, wherein the computer-readable storage medium stores machine-executable instructions, and when the machine-executable instructions are called and run by a processor, the machine-executable instructions cause the processor to run the method according to any one of the first aspects.

[0017] In an embodiment of the present invention, a method for extracting a high-fidelity three-dimensional diffracted wave signal is provided, including: obtaining post-stack seismic data and migration velocity, where the post-stack seismic data includes: three-dimensional reflected waves and three-dimensional diffracted waves; migrating the post-stack seismic data using the migration velocity to obtain the migrated post-stack seismic data, where in the migrated post-stack seismic data, the three-dimensional reflected waves maintain a linear feature and the three-dimensional diffracted waves converge to a focal point; calculating the local dip of the migrated post-stack seismic data, where the local dip of the migrated post-stack seismic data is the local dip of the three-dimensional reflected waves; calculating the local dip of the post-stack seismic data based on the local dip of the migrated post-stack seismic data; performing mean filtering on the post-stack seismic data according to the local dip of the post-stack seismic data to obtain three-dimensional reflected waves, and then calculating three-dimensional diffracted waves based on the post-stack seismic data and the three-dimensional reflected waves. As can be seen from the above description, in the method for extracting a high-fidelity three-dimensional diffracted wave signal of the present invention, the post-stack seismic data is migrated using the migration velocity, and in the obtained migrated post-stack seismic data, the three-dimensional reflected waves maintain a linear feature and the three-dimensional diffracted waves converge to a focal point. In this way, by calculating the local dip in the migrated post-stack seismic data, the three-dimensional reflected waves and the three-dimensional diffracted waves can be effectively distinguished, avoiding their aliasing, that is, the local dip of the obtained migrated post-stack seismic data is the accurate local dip of the three-dimensional reflected waves. Furthermore, the local dip of the migrated post-stack seismic data is then converted into the local dip of the post-stack seismic data. In this way, after performing mean filtering on the post-stack seismic data based on the accurate local dip of the post-stack seismic data, the obtained three-dimensional reflected waves have good accuracy and high quality. Finally, the three-dimensional diffracted waves calculated based on the post-stack seismic data and the high-quality three-dimensional reflected waves have good quality and no damage, that is, the extraction of the high-fidelity three-dimensional diffracted wave signal is realized, alleviating the technical problems of poor quality and damage of the three-dimensional diffracted wave signal extracted by the prior art. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] In order to more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the following will briefly introduce the drawings required for use in the description of the specific embodiments or the prior art. Obviously, the following drawings are some embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other drawings can also be obtained based on these drawings.

[0019] Figure 1 It is a flowchart of a method for extracting a high-fidelity three-dimensional diffracted wave signal provided by an embodiment of the present invention; Figure 2 It is a schematic diagram of the dip and azimuth of the normal vector provided by an embodiment of the present invention; Figure 3 It is a schematic diagram of a device for extracting a high-fidelity three-dimensional diffracted wave signal provided by an embodiment of the present invention; Figure 4 Schematic diagram of an electronic device provided by an embodiment of the present invention. Detailed implementation manners

[0020] The technical solutions of the present invention will be clearly and completely described below in conjunction with the embodiments. Obviously, the described embodiments are some, but not all, of the embodiments of the present invention. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the protection scope of the present invention.

[0021] The quality of the three-dimensional diffracted wave signal extracted by the traditional technology is poor and damaged.

[0022] Based on this, in the method for extracting a high-fidelity three-dimensional diffracted wave signal of the present invention, post-stack seismic data is migrated using the migration velocity. In the migrated post-stack seismic data obtained, the three-dimensional reflected wave maintains a linear feature, and the three-dimensional diffracted wave converges to the focal point. In this way, by calculating the local dip in the migrated post-stack seismic data, the three-dimensional reflected wave and the three-dimensional diffracted wave can be effectively distinguished, avoiding the aliasing of the two. That is, the local dip of the migrated post-stack seismic data obtained is the local dip of the accurate three-dimensional reflected wave. Furthermore, the local dip of the migrated post-stack seismic data is then converted into the local dip of the post-stack seismic data. In this way, after performing mean filtering on the post-stack seismic data based on the accurate local dip of the post-stack seismic data, the obtained three-dimensional reflected wave has good accuracy and high quality. Finally, the quality of the three-dimensional diffracted wave calculated based on the post-stack seismic data and the high-quality three-dimensional reflected wave is good and undamaged, that is, the extraction of the high-fidelity three-dimensional diffracted wave signal is realized.

[0023] For ease of understanding of this embodiment, first, a method for extracting a high-fidelity three-dimensional diffracted wave signal disclosed in an embodiment of the present invention will be introduced in detail.

[0024] Embodiment 1: According to an embodiment of the present invention, an embodiment of a method for extracting a high-fidelity three-dimensional diffracted wave signal is provided. It should be noted that the steps shown in the flowchart of the accompanying drawings can be executed in a computer system such as a set of computer-executable instructions, and although the logical order is shown in the flowchart, in some cases, the steps shown or described can be executed in a different order than here.

[0025] Figure 1 is a flowchart of a method for extracting a high-fidelity three-dimensional diffracted wave signal according to an embodiment of the present invention. As Figure 1 shown, the method includes the following steps: Step S102, obtaining post-stack seismic data and migration velocity, where the post-stack seismic data includes: three-dimensional reflected wave and three-dimensional diffracted wave; Specifically, the post-stack seismic data can be expressed as , and the migration velocity can be expressed as , abbreviated as , represents the abscissa before migration, represents the ordinate before migration, represents the recording time, represents the abscissa after migration, represents the ordinate after migration, represents the time after migration.

[0026] Step S104: Migrate the post-stack seismic data using the migration velocity to obtain the post-stack seismic data after migration. Among them, in the post-stack seismic data after migration, the three-dimensional reflected wave maintains a linear feature, and the three-dimensional diffracted wave converges to the focal point; Specifically, after the post-stack seismic data is migrated, the three-dimensional reflected wave is in place but still maintains a local linear feature, while the three-dimensional diffracted wave will converge to the focal point. Based on this phenomenon, subsequent local dip calculation in the post-stack seismic data after migration can effectively distinguish the three-dimensional reflected wave and the three-dimensional diffracted wave, avoiding their aliasing. That is to say, the local dip of the post-stack seismic data after calculation is the local dip of the accurate three-dimensional reflected wave.

[0027] Step S106: Calculate the local dip of the post-stack seismic data after migration, where the local dip of the post-stack seismic data after migration is the local dip of the three-dimensional reflected wave; Step S108: Calculate the local dip of the post-stack seismic data based on the local dip of the post-stack seismic data after migration; Step S110: Perform mean filtering on the post-stack seismic data according to the local dip of the post-stack seismic data to obtain the three-dimensional reflected wave, and then calculate the three-dimensional diffracted wave based on the post-stack seismic data and the three-dimensional reflected wave.

[0028] The principle of the present invention is briefly introduced below: The post-stack seismic data contains both three-dimensional reflected waves and three-dimensional diffracted waves. Among them, the three-dimensional reflected wave is linear, and the three-dimensional diffracted wave is hyperbolic. If the three-dimensional reflected wave and the three-dimensional diffracted wave are separated, the traditional method is to directly calculate the local dip of the post-stack seismic data, use it as the local dip of the three-dimensional reflected wave, and then perform mean filtering on the post-stack seismic data along the local dip of the post-stack seismic data (i.e., the local dip of the three-dimensional reflected wave) to calculate the three-dimensional reflected wave. Finally, subtract the calculated three-dimensional reflected wave from the post-stack seismic data to obtain the three-dimensional diffracted wave.

[0029] In the above process, although the three-dimensional diffracted wave is hyperbolic, there are also certain local linear characteristics at its top. Therefore, in the local dip of the post-stack seismic data calculated, a part of the local dip of the three-dimensional diffracted wave is also included. Subsequently, when the post-stack seismic data is subjected to mean filtering along the local dip of the post-stack seismic data, a part of the three-dimensional diffracted wave is also aliased in the calculated three-dimensional reflected wave. Therefore, after subtracting the post-stack seismic data from the three-dimensional reflected wave with some three-dimensional diffracted waves aliased, the obtained three-dimensional diffracted wave is damaged and of poor quality.

[0030] Based on the above analysis, it can be seen that the key is to accurately calculate the local dip of the three-dimensional reflected wave. Therefore, the inventor designed the solution of the present invention, specifically: the post-stack seismic data is migrated using the migration velocity. In the migrated post-stack seismic data obtained, the three-dimensional reflected wave maintains a linear characteristic, and the three-dimensional diffracted wave converges to the focal point. In this way, the local dip is calculated in the migrated post-stack seismic data, and the local dip of the migrated post-stack seismic data calculated is the local dip of the three-dimensional reflected wave without being doped with the local dip of the three-dimensional diffracted wave accurately. Furthermore, the local dip of the migrated post-stack seismic data is then converted into the local dip of the post-stack seismic data. Finally, after the post-stack seismic data is subjected to mean filtering using the local dip of the post-stack seismic data, an accurate three-dimensional reflected wave can be obtained. Ultimately, high-fidelity three-dimensional diffracted waves can be extracted through difference calculation.

[0031] In an embodiment of the present invention, a method for extracting a high-fidelity three-dimensional diffracted wave signal is provided, including: obtaining post-stack seismic data and migration velocity, where the post-stack seismic data includes: three-dimensional reflected waves and three-dimensional diffracted waves; migrating the post-stack seismic data using the migration velocity to obtain the migrated post-stack seismic data, where in the migrated post-stack seismic data, the three-dimensional reflected waves maintain linear characteristics and the three-dimensional diffracted waves converge to a focal point; calculating the local dip of the migrated post-stack seismic data, where the local dip of the migrated post-stack seismic data is the local dip of the three-dimensional reflected waves; calculating the local dip of the post-stack seismic data based on the local dip of the migrated post-stack seismic data; performing mean filtering on the post-stack seismic data according to the local dip of the post-stack seismic data to obtain three-dimensional reflected waves, and then calculating three-dimensional diffracted waves based on the post-stack seismic data and the three-dimensional reflected waves. Through the above description, it can be seen that in the method for extracting a high-fidelity three-dimensional diffracted wave signal of the present invention, the post-stack seismic data is migrated using the migration velocity, and in the obtained migrated post-stack seismic data, the three-dimensional reflected waves maintain linear characteristics and the three-dimensional diffracted waves converge to a focal point. In this way, by calculating the local dip in the migrated post-stack seismic data, the three-dimensional reflected waves and the three-dimensional diffracted waves can be effectively distinguished, avoiding their aliasing, that is, the local dip of the obtained migrated post-stack seismic data is the accurate local dip of the three-dimensional reflected waves. Furthermore, the local dip of the migrated post-stack seismic data is then converted into the local dip of the post-stack seismic data. In this way, after performing mean filtering on the post-stack seismic data based on the accurate local dip of the post-stack seismic data, the obtained three-dimensional reflected waves have good accuracy and high quality. Finally, the three-dimensional diffracted waves calculated based on the post-stack seismic data and the high-quality three-dimensional reflected waves have good quality and no damage, that is, the extraction of the high-fidelity three-dimensional diffracted wave signal is realized, alleviating the technical problems of poor quality and damage of the three-dimensional diffracted wave signal extracted by the prior art.

[0032] The above content briefly introduces the method for extracting a high-fidelity three-dimensional diffracted wave signal of the present invention, and the following will describe the specific content involved in detail.

[0033] In an alternative embodiment of the present invention, migrating the post-stack seismic data using the migration velocity specifically includes the following steps: Calculating the formula according to the migrated post-stack seismic data Calculating the migrated post-stack seismic data, where, represents the migrated post-stack seismic data, represents the post-stack seismic data, represents the Dirac function, represents the abscissa before migration, represents the ordinate before migration, represents the recording time, represents the migration velocity, represents the abscissa after offset, represents the ordinate after offset, represents the time after offset.

[0034] It should be noted that in the present invention, the same letter represents the same physical meaning, and the physical meaning of the same letter that appears again in the following text can refer to the relevant description in the previous text.

[0035] In an alternative embodiment of the present invention, calculating the local dip angle of the post-stack seismic data after offset specifically includes the following steps: (1) According to the calculation formula of the local dip angle of the X plane calculate the local dip angle of the X plane of the post-stack seismic data after offset, where represents the local dip angle of the X plane of the post-stack seismic data after offset, represents the post-stack seismic data after offset, represents the abscissa after offset, represents the time after offset; Specifically, along the X plane (i.e., Y is a constant), according to the plane wave equation, we have: , where represents the local dip angle of the X plane of the post-stack seismic data after offset.

[0036] We can obtain: ; In the above formula, and can be obtained by the finite difference method:

[0037]

[0038] In the above formula, and respectively represent the spatial sampling interval and the time sampling interval.

[0039] It should be noted that is the abbreviation of in the previous text.

[0040] (2) According to the calculation formula of the local dip angle of the Y plane calculate the local dip angle of the Y plane of the post-stack seismic data after offset, where represents the local dip angle of the Y plane of the post-stack seismic data after offset, represents the post-stack seismic data after offset, represents the ordinate after offset, represents the time after offset; Specifically, the calculation process of the local dip angle of the Y plane of the post-stack seismic data after migration is similar to that of the local dip angle of the X plane of the post-stack seismic data after migration, which will not be elaborated here.

[0041] (3) Use the local dip angle of the X plane of the post-stack seismic data after migration and the local dip angle of the Y plane of the post-stack seismic data after migration as the local dip angle of the post-stack seismic data after migration.

[0042] In an alternative embodiment of the present invention, calculating the local dip angle of the post-stack seismic data based on the local dip angle of the post-stack seismic data after migration specifically includes the following steps: (1) Calculate the local dip angle of the X plane of the post-stack seismic data according to the local dip angle conversion formula of the X plane where, represents the local dip angle of the X plane of the post-stack seismic data, represents the local dip angle of the X plane of the post-stack seismic data after migration, represents the local dip angle of the Y plane of the post-stack seismic data after migration, represents the migration velocity, , , ; In the above conversion formula, the coordinates and time have the following relationship: , , .

[0043] (2) Calculate the local dip angle of the Y plane of the post-stack seismic data according to the local dip angle conversion formula of the Y plane where, represents the local dip angle of the Y plane of the post-stack seismic data, represents the local dip angle of the X plane of the post-stack seismic data after migration, represents the local dip angle of the Y plane of the post-stack seismic data after migration, represents the migration velocity; Specifically, the above two conversion formulas are derived as follows: The normal vector of the reflection plane can be expressed as: where, and respectively represent the dip angle and azimuth angle of the normal vector, as shown in Figure 2 .

[0044] Then the local dip angle of the post-stack seismic data can be expressed as:

[0045]

[0046] Then the local dip angle of the post-stack seismic data after migration can be expressed as:

[0047]

[0048] The coordinates and time of the post-stack seismic data after migration and the post-stack seismic data have the following relationship:

[0049]

[0050]

[0051] Combining the above formulas, it can be deduced that:

[0052]

[0053] In the above conversion formula, the coordinates and time have the following relationship: , , .

[0054] (3) Take the local dip angle of the X plane of the post-stack seismic data and the local dip angle of the Y plane of the post-stack seismic data as the local dip angle of the post-stack seismic data.

[0055] In an alternative embodiment of the present invention, mean filtering is performed on the post-stack seismic data according to the local dip angle of the post-stack seismic data, which specifically includes the following steps: (1) Perform mean filtering on the post-stack seismic data along the X direction according to the local dip angle of the X plane of the post-stack seismic data to obtain the seismic data after mean filtering along the X direction; Specifically, perform mean filtering along the X direction: , represents the seismic data after mean filtering along the X direction, represents the local dip angle of the X plane of the post-stack seismic data, k represents the number of sampling points, represents the spatial sampling interval along the X direction.

[0056] (2) Perform mean filtering on the seismic data after mean filtering along the X direction along the Y direction according to the local dip angle of the X plane of the post-stack seismic data to obtain a three-dimensional reflection wave.

[0057] Specifically, perform mean filtering along the Y direction: , represents the three-dimensional reflection wave, represents the local dip angle of the Y plane of the post-stack seismic data, k represents the number of sampling points, represents the spatial sampling interval along the Y direction, represents the abscissa after mean filtering along the X direction, represents the time after mean filtering along the X direction.

[0058] In an alternative embodiment of the present invention, a three-dimensional diffracted wave is calculated based on the post-stack seismic data and the three-dimensional reflected wave, and the specific steps are as follows: According to the three-dimensional diffracted wave calculation formula calculate the three-dimensional diffracted wave, where, represents the three-dimensional diffracted wave, represents the post-stack seismic data, represents the three-dimensional reflected wave.

[0059] The method for extracting the high-fidelity three-dimensional diffracted wave signal of the present invention is different from the conventional method. Instead of directly calculating the local dip angle in the post-stack seismic data, it first calculates the local dip angle of the post-stack seismic data after migration, and then converts it into the local dip angle of the post-stack seismic data. After the post-stack seismic data is migrated, the three-dimensional reflected wave is in place, but still maintains the local linear feature, while the three-dimensional diffracted wave will converge to the focal point. Based on this phenomenon, calculating the local dip angle in the post-stack seismic data after migration can effectively distinguish the three-dimensional reflected wave and the three-dimensional diffracted wave, avoid the aliasing of the two, and improve the separation quality of the three-dimensional diffracted wave.

[0060] Specifically, using the mapping relationship (i.e., the conversion formula) before and after the seismic data migration, constructing the local dip angle of the post-stack seismic data with the local dip angle of the post-stack seismic data after migration, and then performing three-dimensional diffracted wave separation (i.e., mean filtering) along two directions in sequence, finally realizing the high-fidelity extraction of the three-dimensional diffracted wave signal. It can be used for the extraction of the three-dimensional diffracted wave field in three-dimensional space and complex geological conditions, and accurately locate geological discontinuities, such as faults, collapse columns, etc.

[0061] Embodiment 2: The embodiment of the present invention also provides an apparatus for extracting a high-fidelity three-dimensional diffracted wave signal. The apparatus for extracting a high-fidelity three-dimensional diffracted wave signal is mainly used to execute the method for extracting a high-fidelity three-dimensional diffracted wave signal provided in Embodiment 1 of the present invention. The following is a specific introduction to the apparatus for extracting a high-fidelity three-dimensional diffracted wave signal provided in the embodiment of the present invention.

[0062] Figure 3 is a schematic diagram of an apparatus for extracting a high-fidelity three-dimensional diffracted wave signal according to an embodiment of the present invention, as Figure 3 shown, the apparatus mainly includes: an acquisition unit 10, a migration unit 20, a first calculation unit 30, a second calculation unit 40, and a mean filtering unit 50, where: An acquisition unit for acquiring post-stack seismic data and migration velocity, wherein the post-stack seismic data includes: three-dimensional reflected waves and three-dimensional diffracted waves; A migration unit for migrating the post-stack seismic data using the migration velocity to obtain the migrated post-stack seismic data, wherein in the migrated post-stack seismic data, the three-dimensional reflected waves maintain a linear feature and the three-dimensional diffracted waves converge to a focal point; A first calculation unit for calculating the local dip of the migrated post-stack seismic data, wherein the local dip of the migrated post-stack seismic data is the local dip of the three-dimensional reflected waves; A second calculation unit for calculating the local dip of the post-stack seismic data based on the local dip of the migrated post-stack seismic data; A mean filtering unit for performing mean filtering on the post-stack seismic data according to the local dip of the post-stack seismic data to obtain three-dimensional reflected waves, and then calculating three-dimensional diffracted waves based on the post-stack seismic data and the three-dimensional reflected waves.

[0063] In an embodiment of the present invention, there is provided an apparatus for extracting a high-fidelity three-dimensional diffracted wave signal, including: obtaining post-stack seismic data and migration velocity, wherein the post-stack seismic data includes: three-dimensional reflected waves and three-dimensional diffracted waves; migrating the post-stack seismic data using the migration velocity to obtain the migrated post-stack seismic data, wherein in the migrated post-stack seismic data, the three-dimensional reflected waves maintain linear characteristics and the three-dimensional diffracted waves converge to a focal point; calculating the local dip of the migrated post-stack seismic data, wherein the local dip of the migrated post-stack seismic data is the local dip of the three-dimensional reflected waves; calculating the local dip of the post-stack seismic data based on the local dip of the migrated post-stack seismic data; performing mean filtering on the post-stack seismic data according to the local dip of the post-stack seismic data to obtain three-dimensional reflected waves, and then calculating three-dimensional diffracted waves based on the post-stack seismic data and the three-dimensional reflected waves. As can be seen from the above description, in the apparatus for extracting a high-fidelity three-dimensional diffracted wave signal of the present invention, the post-stack seismic data is migrated using the migration velocity, and in the obtained migrated post-stack seismic data, the three-dimensional reflected waves maintain linear characteristics and the three-dimensional diffracted waves converge to a focal point. In this way, by calculating the local dip in the migrated post-stack seismic data, the three-dimensional reflected waves and the three-dimensional diffracted waves can be effectively distinguished, avoiding their aliasing, that is, the local dip of the obtained migrated post-stack seismic data is the accurate local dip of the three-dimensional reflected waves. Furthermore, the local dip of the migrated post-stack seismic data is then converted into the local dip of the post-stack seismic data. In this way, after performing mean filtering on the post-stack seismic data based on the accurate local dip of the post-stack seismic data, the obtained three-dimensional reflected waves have good accuracy and high quality. Finally, the three-dimensional diffracted waves calculated based on the post-stack seismic data and the high-quality three-dimensional reflected waves have good quality and no damage, that is, the extraction of the high-fidelity three-dimensional diffracted wave signal is realized, alleviating the technical problems of poor quality and damage of the three-dimensional diffracted wave signal extracted in the prior art.

[0064] Optionally, the migration unit is further configured to: calculate the formula according to the migrated post-stack seismic data Calculate the migrated post-stack seismic data, wherein, Represents the migrated post-stack seismic data, Represents the post-stack seismic data, Represents the Dirac function, Represents the abscissa before migration, Represents the ordinate before migration, Represents the recording time, Represents the migration velocity, Represents the abscissa after migration, Represents the ordinate after migration, Represents the time after migration.

[0065] Optionally, the first calculation unit is further configured to: calculate the formula according to the local dip of the X plane Calculate the local dip angle of the post-stack seismic data in the X plane after migration, where represents the local dip angle of the post-stack seismic data in the X plane after migration, represents the post-stack seismic data after migration, represents the migrated abscissa, represents the migrated time; calculate the local dip angle of the post-stack seismic data in the Y plane according to the calculation formula of the local dip angle in the Y plane Calculate the local dip angle of the post-stack seismic data in the Y plane after migration, where represents the local dip angle of the post-stack seismic data in the Y plane after migration, represents the post-stack seismic data after migration, represents the migrated ordinate, represents the migrated time; use the local dip angle of the post-stack seismic data in the X plane after migration and the local dip angle of the post-stack seismic data in the Y plane after migration as the local dip angle of the post-stack seismic data after migration.

[0066] Optionally, the second calculation unit is further configured to: calculate the local dip angle of the post-stack seismic data in the X plane according to the conversion formula of the local dip angle in the X plane Calculate the local dip angle of the post-stack seismic data in the X plane, where represents the local dip angle of the post-stack seismic data in the X plane, represents the local dip angle of the post-stack seismic data in the X plane after migration, represents the local dip angle of the post-stack seismic data in the Y plane after migration, represents the migration velocity, , , ; calculate the local dip angle of the post-stack seismic data in the Y plane according to the conversion formula of the local dip angle in the Y plane Calculate the local dip angle of the post-stack seismic data in the Y plane, where represents the local dip angle of the post-stack seismic data in the Y plane, represents the local dip angle of the post-stack seismic data in the X plane after migration, represents the local dip angle of the post-stack seismic data in the Y plane after migration, represents the migration velocity; use the local dip angle of the post-stack seismic data in the X plane and the local dip angle of the post-stack seismic data in the Y plane as the local dip angle of the post-stack seismic data.

[0067] Optionally, the mean filtering unit is further configured to: perform mean filtering on the post-stack seismic data along the X direction according to the local dip angle of the post-stack seismic data in the X plane to obtain the seismic data after mean filtering along the X direction; perform mean filtering on the seismic data after mean filtering along the X direction along the Y direction according to the local dip angle of the post-stack seismic data in the X plane to obtain the three-dimensional reflection wave.

[0068] Optionally, the mean filtering unit is further configured to: calculate according to the three-dimensional diffraction wave calculation formula Calculating a three-dimensional diffracted wave, wherein, represents a three-dimensional diffracted wave, represents post-stack seismic data, represents a three-dimensional reflected wave.

[0069] The device provided by the embodiment of the present invention has the same implementation principle and the same technical effects as those of the foregoing method embodiment. For a brief description, for the parts not mentioned in the device embodiment, reference may be made to the corresponding content in the foregoing method embodiment.

[0070] As Figure 4 shown, an electronic device 600 provided by an embodiment of the present application includes: a processor 601, a memory 602, and a bus. The memory 602 stores machine-readable instructions executable by the processor 601. When the electronic device runs, communication between the processor 601 and the memory 602 is carried out through the bus. The processor 601 executes the machine-readable instructions to perform the steps of the method for extracting a high-fidelity three-dimensional diffracted wave signal as described above.

[0071] Specifically, the foregoing memory 602 and processor 601 can be general memories and processors, and no specific limitation is made here. When the processor 601 runs the computer program stored in the memory 602, it can execute the method for extracting a high-fidelity three-dimensional diffracted wave signal as described above.

[0072] The processor 601 may be an integrated circuit chip with signal processing capabilities. In the implementation process, each step of the above method can be completed by the integrated logic circuit in the hardware of the processor 601 or instructions in the form of software. The above-mentioned processor 601 may be a general-purpose processor, including a central processing unit (CPU for short), a network processor (NP for short), etc.; it may also be a digital signal processor (DSP for short), an application specific integrated circuit (ASIC for short), a field-programmable gate array (FPGA for short), or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components. It can implement or execute the various methods, steps, and logic block diagrams disclosed in the embodiments of the present application. The general-purpose processor may be a microprocessor or the processor may also be any conventional processor, etc. The steps of the method disclosed in combination with the embodiments of the present application can be directly embodied as being executed and completed by a hardware decoding processor, or executed and completed by a combination of hardware and software modules in the decoding processor. The software module may be located in a mature storage medium in the art such as a random access memory, a flash memory, a read-only memory, a programmable read-only memory, or an electrically erasable programmable memory, a register, etc. This storage medium is located in the memory 602, and the processor 601 reads the information in the memory 602 and combines its hardware to complete the steps of the above method.

[0073] Corresponding to the above method for extracting high-fidelity three-dimensional diffracted wave signals, an embodiment of the present application further provides a computer-readable storage medium. The computer-readable storage medium stores machine-executable instructions. When the computer-executable instructions are called and run by a processor, the computer-executable instructions cause the processor to run the steps of the above method for extracting high-fidelity three-dimensional diffracted wave signals.

[0074] The device for extracting high-fidelity three-dimensional diffracted wave signals provided by the embodiments of the present application may be specific hardware on a device or software or firmware installed on the device, etc. For the device provided by the embodiments of the present application, its implementation principle and the technical effects produced are the same as those of the foregoing method embodiments. For the sake of brief description, for the parts not mentioned in the device embodiments, reference may be made to the corresponding content in the foregoing method embodiments. Those skilled in the art can clearly understand that for the convenience and brevity of description, the specific working processes of the systems, devices, and units described above can all refer to the corresponding processes in the above method embodiments and will not be elaborated here.

[0075] In the embodiments provided in the present application, it should be understood that the disclosed devices and methods can be implemented in other ways. The device embodiments described above are merely illustrative. For example, the division of the units is only a logical function division. In actual implementation, there may be other division methods. For another example, multiple units or components can be combined or integrated into another system, or some features can be ignored or not executed. Another point is that the displayed or discussed coupling or direct coupling or communication connection between each other can be through some communication interfaces. The indirect coupling or communication connection of the devices or units can be in electrical, mechanical or other forms.

[0076] For another example, the flowcharts and block diagrams in the accompanying drawings show the possible architectures, functions, and operations of devices, methods, and computer program products according to multiple embodiments of the present application. In this regard, each block in the flowchart or block diagram may represent a module, a program segment, or a part of code, and the module, program segment, or part of code contains one or more executable instructions for implementing the specified logical function. It should also be noted that in some alternative implementations, the functions marked in the blocks may occur in a different order than that marked in the accompanying drawings. For example, two consecutive blocks can actually be executed substantially in parallel, and they can sometimes be executed in the reverse order, depending on the functions involved. It should also be noted that each block in the block diagram and / or flowchart, as well as the combination of blocks in the block diagram and / or flowchart, can be implemented by a dedicated hardware-based system that performs the specified functions or actions, or can be implemented by a combination of dedicated hardware and computer instructions.

[0077] The units described as separate components may or may not be physically separated. The components shown as units may or may not be physical units, that is, they can be located in one place, or can be distributed to multiple network units. Some or all of the units can be selected according to actual needs to achieve the purpose of the solution of this embodiment.

[0078] In addition, the functional units in the embodiments provided in the present application can be integrated in one processing unit, or each unit can exist physically alone, or two or more units can be integrated in one unit.

[0079] When the above-mentioned functions are implemented in the form of software functional units and sold or used as independent products, they can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of this application, in essence, or the part that contributes to the prior art, or a part of this technical solution, can be embodied in the form of a software product. This computer software product is stored in a storage medium and includes several instructions for causing an electronic device (which may be a personal computer, a server, or a network device, etc.) to execute all or part of the steps of the method for extracting high-fidelity three-dimensional diffraction wave signals described in various embodiments of this application. The aforementioned storage medium includes: various media such as USB flash drives, mobile hard disks, read-only memories (ROM for short), random access memories (RAM for short), magnetic disks, or optical discs that can store program codes.

[0080] It should be noted that: similar reference numerals and letters represent similar items in the following drawings. Therefore, once an item is defined in one drawing, it does not need to be further defined and explained in subsequent drawings. In addition, the terms "first", "second", "third", etc. are only used for descriptive distinction and cannot be understood as indicating or implying relative importance.

[0081] Finally, it should be noted that: the above-mentioned embodiments are only specific implementation manners of this application, used to illustrate the technical solution of this application, rather than limiting it. The protection scope of this application is not limited thereto. Although this application has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that: any person skilled in the art within the technical scope disclosed in this application can still modify the technical solutions recorded in the foregoing embodiments, or can easily think of changes, or perform equivalent replacements on some of the technical features; and these modifications, changes, or replacements do not make the essence of the corresponding technical solutions deviate from the scope of the technical solutions of the embodiments of this application. All should be covered within the protection scope of this application. Therefore, the protection scope of this application should be subject to the protection scope of the claims.

Claims

1. A method for extracting high-fidelity three-dimensional diffraction wave signals, characterized in that: include: Acquiring post-stack seismic data and migration velocity, wherein the post-stack seismic data includes: three-dimensional reflection waves and three-dimensional diffraction waves; Migrating the post-stack seismic data using the migration velocity to obtain migrated post-stack seismic data, wherein in the migrated post-stack seismic data, the three-dimensional reflection wave maintains a linear feature, and the three-dimensional diffraction wave converges to a focus point; Calculating the local dip of the migrated post-stack seismic data, wherein the local dip of the migrated post-stack seismic data is the local dip of the three-dimensional reflection wave; calculating the local dip of the post-stack seismic data based on the local dip of the migrated post-stack seismic data; The post-stack seismic data is mean filtered according to the local dip angle of the post-stack seismic data to obtain the three-dimensional reflection wave, and then the three-dimensional diffraction wave is calculated according to the post-stack seismic data and the three-dimensional reflection wave.

2. The method according to claim 1, characterized in that: Migrating the post-stack seismic data using the migration velocity includes: Calculate the formula based on the migrated post-stack seismic data Calculate the post-stack seismic data after the migration, wherein, represents the post-stack seismic data after the migration, represents the post-stack seismic data, represents the Dirac function, represents the horizontal coordinate before the offset, Indicates the ordinate before offset, Indicates the recording time. represents the offset speed, represents the horizontal coordinate after the offset, represents the vertical coordinate after the offset, Indicates the time after the offset.

3. The method according to claim 2, characterized in that Calculating the local dip of the migrated post-stack seismic data includes: Calculation formula based on the local inclination angle of the X plane The local dip angle of the X-plane of the migrated post-stack seismic data is calculated, wherein: represents the local dip in the X plane of the post-stack seismic data after the migration, represents the post-stack seismic data after the migration, represents the horizontal coordinate after the offset, Indicates the time after the offset; Calculation formula based on the local inclination of the Y plane The local dip angle of the Y plane of the migrated post-stack seismic data is calculated, where: represents the local dip angle of the Y plane of the post-stack seismic data after the migration, represents the post-stack seismic data after the migration, represents the vertical coordinate after the offset, Indicates the time after the offset; The local dip angle of the X-plane of the migrated post-stack seismic data and the local dip angle of the Y-plane of the migrated post-stack seismic data are used as the local dip angle of the migrated post-stack seismic data.

4. The method according to claim 3, characterized in that: Calculating the local dip of the post-stack seismic data based on the local dip of the migrated post-stack seismic data includes: According to the local inclination conversion formula of the X plane Calculate the X-plane local dip of the post-stack seismic data, where: represents the local dip angle of the X-plane of the post-stack seismic data, represents the local dip in the X plane of the post-stack seismic data after the migration, represents the local dip angle of the Y plane of the post-stack seismic data after the migration, represents the offset speed, , , ; According to the local inclination conversion formula of the Y plane Calculate the Y-plane local dip angle of the post-stack seismic data, where: represents the local dip angle of the Y plane of the post-stack seismic data, represents the local dip in the X plane of the post-stack seismic data after the migration, represents the local dip angle of the Y plane of the post-stack seismic data after the migration, represents the offset speed; The X-plane local dip angle of the post-stack seismic data and the Y-plane local dip angle of the post-stack seismic data are used as the local dip angle of the post-stack seismic data.

5. The method according to claim 4, characterized in that Mean filtering is performed on the post-stack seismic data according to the local dip angle of the post-stack seismic data, comprising: Performing mean filtering on the post-stack seismic data along X according to the local dip angle of the X plane of the post-stack seismic data to obtain seismic data after mean filtering along X; The seismic data after the mean filtering along X is mean filtered along Y according to the local dip angle of X plane of the post-stack seismic data to obtain the three-dimensional reflection wave.

6. The method according to claim 1, characterized in that Calculating the three-dimensional diffraction wave according to the post-stack seismic data and the three-dimensional reflection wave includes: According to the three-dimensional diffraction wave calculation formula The three-dimensional diffraction wave is calculated, wherein, represents the three-dimensional diffraction wave, represents the post-stack seismic data, represents the three-dimensional reflected wave.

7. A device for extracting high-fidelity three-dimensional diffraction wave signals, characterized in that: include: An acquisition unit, used for acquiring post-stack seismic data and migration velocity, wherein the post-stack seismic data includes: three-dimensional reflection waves and three-dimensional diffraction waves; an offset unit, configured to offset the post-stack seismic data using the offset velocity to obtain the offset post-stack seismic data, wherein in the offset post-stack seismic data, the three-dimensional reflection wave maintains a linear feature, and the three-dimensional diffraction wave converges to a focus point; A first calculation unit is used to calculate the local dip of the migrated post-stack seismic data, wherein the local dip of the migrated post-stack seismic data is the local dip of the three-dimensional reflection wave; A second calculation unit, configured to calculate the local dip of the post-stack seismic data based on the local dip of the migrated post-stack seismic data; A mean filtering unit is used to perform mean filtering on the post-stack seismic data according to the local dip angle of the post-stack seismic data to obtain the three-dimensional reflection wave, and then calculate the three-dimensional diffraction wave according to the post-stack seismic data and the three-dimensional reflection wave.

8. The device according to claim 7, characterized in that The offset unit is also used for: Calculate the formula based on the migrated post-stack seismic data Calculate the post-stack seismic data after the migration, wherein, represents the post-stack seismic data after the migration, represents the post-stack seismic data, represents the Dirac function, represents the horizontal coordinate before the offset, Indicates the ordinate before offset, Indicates the recording time. represents the offset speed, represents the horizontal coordinate after the offset, represents the vertical coordinate after the offset, Indicates the time after the offset.

9. An electronic device comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein: When the processor executes the computer program, the steps of the method according to any one of claims 1 to 6 are implemented.

10. A computer-readable storage medium, characterized in that: The computer-readable storage medium stores machine-executable instructions. When the machine-executable instructions are called and executed by a processor, the machine-executable instructions cause the processor to execute the method according to any one of claims 1 to 6.

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