Mountain earthquake data denoising method and device

Abstract

The invention discloses a denoising method and device for mountain earthquake data. The method comprises the following steps: carrying out surface wave suppression on surface waves and scattering components thereof in original mountain earthquake data by adopting a surface wave simulation technology; different frequency components of the seismic data after the surface wave suppression are partitioned, and corresponding abnormal energy amplitude suppression is performed on different regions; executing linear noise suppression of irregular sampling on the seismic data; residual scattering surface waves in the seismic data are removed in a multi-domain combination mode; the signals refracted for multiple times in the seismic data are removed; and suppressing the shallow residual noise of the seismic data in the common offset vector cov domain. The invention provides a technology combination application strategy, and solves the problem that the denoising of the mountain earthquake data is difficult.

Description

Technical Field

[0001] The present invention relates to the field of seismic exploration technology, and in particular to a method and device for denoising mountain seismic data. Background Art

[0002] In mountainous environments, the main types of noise in seismic data include near-surface noise introduced by terrain effects, such as surface wave active scattering noise, multiple refractions, and multipath propagation noise caused by complex geological structures.

[0003] Currently, there are several mainstream methods for denoising mountain seismic data. Wavelet denoising can effectively handle noise introduced by terrain and multipath propagation, distinguishing signal from noise through frequency domain decomposition. Techniques such as frequency-wavenumber (fk) filtering are widely used in seismic data processing, suppressing noise by processing frequency and wavenumber domain information. In recent years, surface wave simulation noise suppression technology has achieved promising results. However, due to the extremely low signal-to-noise ratio of mountain data and the rich and complex noise types, improving the signal-to-noise ratio of the data is difficult, resulting in significant residual noise, a lack of mature processes, and even lack of specific technical solutions for many noise types. Summary of the Invention

[0004] In view of the above problems, the present invention is proposed to provide a method and apparatus for denoising mountain seismic data that overcomes the above problems or at least partially solves the above problems.

[0005] In a first aspect, an embodiment of the present invention provides a method for denoising mountain seismic data, comprising:

[0006] Surface wave simulation technology is used to suppress surface waves and their scattered components in the original mountain seismic data;

[0007] For the seismic data after surface wave suppression, different frequency components are divided into different areas, and the amplitude of the corresponding abnormal energy is suppressed in different areas respectively;

[0008] performing irregularly sampled linear noise suppression on the seismic data;

[0009] Removing residual scattered surface waves from the seismic data by using a multi-domain combination approach;

[0010] removing multiply refracted signals in the seismic data;

[0011] Shallow residual noise is suppressed in the common offset vector cov domain of the seismic data.

[0012] In one embodiment, surface wave simulation technology is used to suppress surface waves and their scattered components in mountain seismic data, including:

[0013] Model the scattering characteristics and establish a scattering model by simulating and analyzing the scattering process;

[0014] Based on the scattering model, the propagation path of the surface wave and the possible scattering are simulated to subtract the scattering component of the surface wave from the original mountain seismic data.

[0015] In one embodiment, the seismic data after surface wave suppression is partitioned into different frequency components, and the amplitude of abnormal energy corresponding to different regions is suppressed, including:

[0016] The seismic data is divided into left arrangement and right arrangement according to different frequency components;

[0017] Abnormal energy amplitude is suppressed for the left-arranged and right-arranged data respectively.

[0018] In one embodiment, suppressing abnormal energy amplitude includes:

[0019] According to the characteristics of the abnormal energy, it is transformed into the shot domain, receiver domain or common center point gather CMP domain for denoising.

[0020] In one embodiment, performing irregularly sampled linear noise suppression on the seismic data includes:

[0021] The linear noise in the seismic data is suppressed by using irregular sampling technology.

[0022] In one embodiment, the residual scattered surface waves in the seismic data are removed by using a multi-domain combination method, including:

[0023] Transforming seismic data into multiple data domains; the data domains include: shot domain, receiver point domain, and common center point gather CMP domain;

[0024] Find the linear law of the scattered surface waves and remove the linear interference by using KL transform or FK transform.

[0025] In one embodiment, removing multiply refracted signals from the seismic data includes:

[0026] The first arrival is used to flatten the single shot and restore the linear characteristics of multiple refractions. The time window is opened and the horizontal phase axis of the time window below the first arrival is suppressed.

[0027] In one embodiment, suppressing shallow residual noise in the common offset vector cov domain of the seismic data includes:

[0028] The seismic data is transformed into the cov domain, and the tilted event in the seismic data is suppressed according to the phase consistency of the cov domain, and then transformed into the shot domain.

[0029] In a second aspect, an embodiment of the present invention provides a denoising device for mountain seismic data, comprising:

[0030] The surface wave suppression module is used to suppress the surface waves and their scattered components in the original mountain seismic data using surface wave simulation technology;

[0031] A partitioned multi-domain suppression module is used to partition the seismic data after surface wave suppression by different frequency components and suppress the amplitude of abnormal energy corresponding to different regions;

[0032] An irregular sampling linear noise suppression module, configured to perform irregular sampling linear noise suppression on the seismic data;

[0033] A multi-domain combination residual surface wave suppression module is used to remove residual scattered surface waves in the seismic data by using a multi-domain combination method;

[0034] a refraction signal removal module, configured to remove multiply refracted signals in the seismic data;

[0035] The shallow noise suppression module is used to suppress the shallow residual noise of the seismic data in the common offset vector cov domain.

[0036] In a third aspect, an embodiment of the present invention provides a computing 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 program, the denoising method for mountain seismic data as described above is implemented.

[0037] In a fourth aspect, 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, the denoising method for mountain seismic data as described above is implemented.

[0038] The beneficial effects of the above technical solutions provided by the embodiments of the present invention include at least:

[0039] The denoising method for mountain seismic data provided by the present invention employs a multi-stage comprehensive denoising strategy, including surface roll simulation suppression, multi-domain anomalous energy noise suppression, residual scattered surface roll suppression, and multiple refraction suppression, ultimately suppressing shallow-layer noise. This multi-stage denoising process effectively suppresses the influence of multiple noise sources, providing a reliable data foundation for resource exploration.

[0040] Other features and advantages of the present invention will be described in the following description, and in part will become apparent from the description, or will be understood by practicing the present invention. The purposes and other advantages of the present invention can be realized and obtained by the structures particularly pointed out in the written description, claims, and drawings.

[0041] The technical solution of the present invention is further described in detail below through the accompanying drawings and embodiments. BRIEF DESCRIPTION OF THE DRAWINGS

[0042] The accompanying drawings are used to provide a further understanding of the present invention and constitute a part of the specification. Together with the embodiments of the present invention, they are used to explain the present invention and do not constitute a limitation of the present invention. In the accompanying drawings:

[0043] Figure 1 Flowchart of a method for denoising mountain seismic data according to an embodiment of the present invention;

[0044] Figure 2A and Figure 2B This is a comparison diagram after surface roll suppression in an embodiment of the present invention;

[0045] Figure 3 A schematic diagram of an example of performing strong amplitude suppression by arrangement according to an embodiment of the present invention;

[0046] Figure 4 A schematic diagram comparing overall suppression of abnormal energy and suppression of abnormal energy in an arrangement according to an embodiment of the present invention;

[0047] Figure 5A and Figure 5B These are the signal diagrams of a single shot before and after linear noise suppression;

[0048] Figure 6A and Figure 6B Schematic diagram of common shot gathers and common receiver gathers in an embodiment of the present invention;

[0049] Figure 7 This is a flowchart of an example of performing KL transformation to remove noise in an embodiment of the present invention;

[0050] Figure 8 1. A signal diagram corresponding to each step of an example of KL transform noise removal in an embodiment of the present invention;

[0051] Figure 9 A schematic diagram of a process for suppressing multiple refractions in an embodiment of the present invention;

[0052] Figure 10 4 is a structural block diagram of a device for denoising mountain seismic data in an embodiment of the present invention. DETAILED DESCRIPTION

[0053] Exemplary embodiments of the present disclosure will be described in more detail below with reference to the accompanying drawings. Although exemplary embodiments of the present disclosure are shown in the accompanying drawings, it should be understood that the present disclosure can be implemented in various forms and should not be limited by the embodiments set forth herein. Rather, these embodiments are provided to enable a more thorough understanding of the present disclosure and to fully convey the scope of the present disclosure to those skilled in the art.

[0054] The denoising method for mountain earthquake data provided by the embodiment of the present invention is as follows: Figure 1 As shown, the following steps are included:

[0055] S11. Use surface wave simulation technology to suppress surface waves and their scattered components in the original mountain seismic data;

[0056] S12. For the seismic data after surface wave suppression, different frequency components are divided into different areas, and the amplitude of the corresponding abnormal energy is suppressed in different areas;

[0057] S13, performing irregular sampling linear noise suppression on seismic data;

[0058] S14, using a multi-domain combination method to remove residual scattered surface waves in the seismic data;

[0059] S15, removing multiply refracted signals in the seismic data;

[0060] S16. Suppressing shallow residual noise in the common offset vector (COV) domain of the seismic data.

[0061] The embodiment of the present invention provides a phased comprehensive denoising strategy, which adopts different noise processing strategies in different stages to deal with different noise sources, thereby solving the problems of conventional denoising technology that cannot completely suppress noise and has poor adaptability, and provides a technology combination application strategy to solve the problem of difficulty in denoising mountain seismic data.

[0062] The specific implementation methods of each of the above steps are described in detail below.

[0063] In one embodiment, in the above step S11, the inventors found that the low-frequency surface waves between 0-10 Hz in mountain seismic data have good regularity, and the surface wave simulation method can be used to suppress noise.

[0064] In mountainous environments, the terrain significantly affects surface waves. Furthermore, due to the complex terrain and structure, surface waves will scatter, further increasing the difficulty of suppressing them. Specifically, in this embodiment of the present invention, the scattering characteristics of surface waves are used for modeling. By simulating and analyzing the scattering process, a scattering model is established.

[0065] Based on the scattering model, by simulating the propagation path of surface waves and the possible scattering caused, the scattering components of surface waves can be subtracted from the original mountain seismic data, which can effectively reduce the interference of surface waves.

[0066] Reference Figure 2A As shown, Figure 2A is the signal diagram of the original single shot, Figure 2B This is the signal diagram after surface wave suppression.

[0067] In one embodiment, in step S12, the abnormal energy is often residual surface waves or noise caused by terrain, artificial, or natural interference sources. In the second stage of the mountain seismic data denoising method provided in this embodiment of the present invention, a multi-domain partitioning approach is used to perform targeted denoising on abnormal noise in different regions.

[0068] For example, the seismic data is divided into left arrangement and right arrangement according to different frequency components;

[0069] Abnormal energy amplitude is suppressed for the left-arranged and right-arranged data respectively.

[0070] Due to the complex geological variations in mountainous areas, abnormal noise can manifest differently. For example, the energy of the noise may vary. Uniformly suppressing abnormal energy can easily lead to insufficient denoising or damage to valid signals. Therefore, in this embodiment of the present invention, by dividing the seismic data into different regions and applying appropriate denoising methods to each, abnormal noise can be more accurately suppressed, improving data clarity.

[0071] For an example of strong amplitude suppression by arrangement, see Figure 3 As shown, the seismic data are divided into left and right arrangements, and then the abnormal energy is suppressed by the arrangement.

[0072] For an example comparing overall suppression of abnormal energy and suppression of abnormal energy in a distributed manner, please refer to Figure 4 As shown, in the signal diagram on the left, the overall suppression of abnormal energy (for example, the same denoising parameters are used overall), resulting in damage to the effective signal (the signal corresponding to the circle), while in the signal diagram on the right, the abnormal signals are suppressed in separate arrangements, and the corresponding denoising operations are used for different arrangements, so there will be no loss of effective signals after overall suppression.

[0073] The suppression of abnormal energy amplitude can be specifically implemented by, for example, transforming the abnormal energy into the shot domain, the receiver domain or the common center point gather CMP domain for denoising according to its characteristics.

[0074] In one embodiment, in step S13, the third stage of the denoising method for mountain seismic data, the present invention introduces irregular sampling technology and linear noise suppression technology specifically for addressing linear noise in mountainous data. Due to the dramatic terrain and complex surface conditions in mountainous areas, seismic observation systems may be designed irregularly. Irregular sampling disrupts the linear behavior of noise, resulting in aliasing and poor linearity. Irregular sampling technology can effectively mitigate this effect, adapting to irregular sampling caused by irregular observation systems and thereby better suppressing linear noise.

[0075] Reference Figure 5A and Figure 5B As shown, Figure 5A This is the signal diagram of a single shot before linear noise suppression. Figure 5B This is the signal diagram of a single shot after linear noise suppression.

[0076] In one embodiment, in the above-mentioned step S14, surface waves and their scattering are the most prominent noise in mountain seismic data, with strong energy and poor regularity. They cannot be completely suppressed after the denoising in the previous steps. In this step S14, the data is transformed into multiple data domains, such as the shot domain, the detection point domain, and the cmp domain, to find the residual linear regularity of the surface waves, and corresponding technologies (Hotelling (KL) transform (i.e., a method of transforming a discrete signal into a string of uncorrelated coefficients), frequency-wavenumber (FK)-based transform, i.e., a method of converting a time domain signal into a frequency-wavenumber domain signal, etc.) are used for suppression.

[0077] For example, refer to Figure 6A and Figure 6B As shown, Figure 6A It is the signal diagram of the common shot gather. Figure 6B It is a common detection point gather. The apparent velocity of the residual surface wave interference common shot point gather is high and basically equivalent to the effective reflection velocity, and it is basically impossible to effectively remove it. However, there is still a certain linear law in the common detection point gather, and it is quite different from the effective reflection.

[0078] Reference Figure 7 As shown in the flowchart, when suppressing, the low-frequency and high-angle linear interference can be removed from the co-detected gathers first, and then KL transformation can be performed to obtain the effective signal and noise. The high-speed and high-frequency interference signal can be further removed from the noise obtained after the transformation. The remaining effective signal is then combined with the effective signal obtained after the previous transformation to form the final effective reflection signal output. The signal change process of each step can be referred to Figure 8 As shown in the figure, there are the signal diagram of the co-detected channel gather, the signal diagram after suppressing the low-frequency and low-speed interference, the noise profile diagram after KL transformation, the signal diagram of suppressing the high-frequency linear interference signal, and the signal diagram of the effective reflection signal output at the end.

[0079] In one embodiment, in the above step S14, the residual scattered surface waves in the seismic data are removed by using a multi-domain combination method, which can be specifically achieved by the following method:

[0080] Transforming seismic data into multiple data domains; the data domains include: shot domain, receiver point domain, and common center point gather CMP domain;

[0081] Find the linear law of the scattered surface waves and remove the linear interference by using KL transform or FK transform.

[0082] In mountain seismic data, surface waves and their scattering are the most prominent noise in mountain data. They have strong energy and poor regularity, and even the denoising steps in the previous steps cannot completely suppress them. In this step, the seismic data is transformed into multiple data domains, such as the shot domain, the receiver point domain, and the CMP domain, to find the residual linear regularity of the surface waves and use corresponding techniques (such as KL transform and fk-based transform) to suppress them.

[0083] Multiple refraction is the phenomenon that seismic waves are repeatedly refracted and propagated in underground complex geological systems. In complex geological environments such as mountains, seismic waves will refract when crossing different stratum interfaces. Due to changes in geological structures, the refraction process may occur multiple times, thereby forming the phenomenon of multiple refraction. This step focuses on the multiple refraction components in the processing data. Because the low-velocity reduction zone of the mountain is thin, the multiple refraction propagation path is short, often showing the characteristics of being parallel to the first arrival. Conventional waveguide removal technology cannot accurately suppress multiple refraction. In one embodiment, in the above-mentioned step S15, the signal of multiple refraction in the seismic data is removed. Specifically, the single shot can be flattened with the first arrival to restore the linear characteristics of multiple refraction, and then the horizontal phase axis is suppressed (opening the time window and then suppressing the horizontal phase axis of the time window below the first arrival), which can better suppress multiple refraction.

[0084] For example, refer to Figure 9 As shown in the figure, after the first arrival correction, the reaction correction is performed, and the linear velocity (4000m / s) is used to accurately identify multiple refractions.

[0085] from Figure 9 It can be seen from the figure that the signal of a single shot after denoising is corrected by the first arrival and then linearly corrected. Finally, the signal obtained after multiple refraction suppression is as follows: Figure 9 The last picture of .

[0086] Using first arrival correction to eliminate speed influence and reaction correction to suppress the window is beneficial to protecting the signal.

[0087] In the COV domain, shallow residual noise is suppressed. Shallow noise is often the remnant of conventional surface rolls and linear noise. It has high frequency and is generally small in scale, making conventional methods often incapable of suppressing it.

[0088] In one embodiment, in the above step S16, the shallow residual noise is suppressed in the common offset vector COV domain of the seismic data, specifically by the following method:

[0089] The seismic data are transformed into the COV domain, and the tilted events in the seismic data are suppressed according to the phase consistency of the COV domain, and then transformed into the shot domain.

[0090] By performing denoising in the COV domain, the residual shallow noise can be suppressed more effectively, thereby further improving the quality of seismic data and facilitating subsequent depth domain modeling.

[0091] The denoising method for mountain seismic data provided by the embodiment of the present invention adopts a multi-stage comprehensive denoising strategy, effectively suppresses the influence of multiple noise sources, and provides a reliable data foundation for the field of resource exploration.

[0092] Based on the same inventive concept, an embodiment of the present invention also provides a method and device for denoising mountain seismic data. Since the principles of the problems solved by these devices and clients are similar to those of the aforementioned method for denoising mountain seismic data, the implementation of the device can refer to the implementation of the aforementioned method, and the repeated parts will not be repeated.

[0093] The embodiment of the present invention provides a denoising device for mountain earthquake data, referring to Figure 10 Shown, including:

[0094] The surface wave suppression module 91 is used to suppress the surface waves and their scattered components in the original mountain seismic data by using the surface wave simulation technology;

[0095] A partitioned multi-domain suppression module 92 is used to partition the seismic data after surface wave suppression into different frequency components and suppress the amplitude of abnormal energy corresponding to different regions;

[0096] An irregular sampling linear noise suppression module 93 is used to perform irregular sampling linear noise suppression on the seismic data;

[0097] A multi-domain combination residual surface wave suppression module 94 is used to remove residual scattered surface waves in the seismic data by using a multi-domain combination method;

[0098] a refraction signal removal module 95, configured to remove multiply refracted signals in the seismic data;

[0099] The shallow noise suppression module 96 is used to suppress the shallow residual noise of the seismic data in the common offset vector cov domain.

[0100] An embodiment of the present invention provides a computing device comprising: a memory, a processor, and a computer program stored in the memory and executable on the processor. When the processor executes the program, the aforementioned mountain seismic data denoising method is implemented.

[0101] An embodiment of the present invention provides a computer-readable storage medium, wherein the computer-readable storage medium stores a computer program. When the computer program is executed by a processor, the computer program implements the aforementioned mountain seismic data denoising method.

[0102] Those skilled in the art will appreciate that embodiments of the present invention may be provided as methods, systems, or computer program products. Thus, the present invention may take the form of an entirely hardware embodiment, an entirely software embodiment, or an embodiment combining software and hardware. Furthermore, the present invention may take the form of a computer program product implemented on one or more computer-usable storage media (including but not limited to magnetic disk storage and optical storage, etc.) containing computer-usable program code.

[0103] The present invention is described with reference to flowcharts and / or block diagrams of methods, devices (systems), and computer program products according to embodiments of the present invention. It should be understood that each process and / or block in the flowcharts and / or block diagrams, as well as combinations of processes and / or blocks in the flowcharts and / or block diagrams, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, a special-purpose computer, an embedded processor, or other programmable data processing device to produce a machine, so that the instructions executed by the processor of the computer or other programmable data processing device generate instructions for implementing the processes in the flowcharts and / or block diagrams. Figure 1 a process or multiple processes and / or boxes Figure 1 A device that provides the functions specified in a block or multiple blocks.

[0104] These computer program instructions may also be stored in a computer readable memory that can direct a computer or other programmable data processing device to work in a specific manner, so that the instructions stored in the computer readable memory produce an article of manufacture comprising an instruction device, which implements the process Figure 1 a process or multiple processes and / or boxes Figure 1 The function specified in one or more boxes.

[0105] These computer program instructions can also be loaded onto a computer or other programmable data processing device so that a series of operational steps are executed on the computer or other programmable device to produce a computer-implemented process, thereby providing the instructions executed on the computer or other programmable device for implementing the process. Figure 1 a process or multiple processes and / or boxes Figure 1 A step that specifies a function in one or more boxes.

[0106] Obviously, those skilled in the art may make various changes and modifications to the present invention without departing from the spirit and scope of the present invention. Thus, if such changes and modifications fall within the scope of the claims and their equivalents, the present invention is intended to include such changes and modifications.

Claims

1. A method for denoising mountain seismic data, characterized in that: include: Surface wave simulation technology is used to suppress surface waves and their scattered components in the original mountain seismic data; For the seismic data after surface wave suppression, different frequency components are divided into different areas, and the amplitude of the corresponding abnormal energy is suppressed in different areas respectively; performing irregularly sampled linear noise suppression on the seismic data; Removing residual scattered surface waves from the seismic data by using a multi-domain combination approach; removing multiply refracted signals in the seismic data; Shallow residual noise is suppressed in the common offset vector cov domain of the seismic data.

2. The method according to claim 1, wherein Surface wave simulation technology is used to suppress surface waves and their scattered components in mountain seismic data, including: Model the scattering characteristics and establish a scattering model by simulating and analyzing the scattering process; Based on the scattering model, the propagation path of the surface wave and the possible scattering are simulated to subtract the scattering component of the surface wave from the original mountain seismic data.

3. The method according to claim 1, wherein The seismic data after surface wave suppression is partitioned into different frequency components, and the amplitude of the corresponding abnormal energy is suppressed in different areas, including: The seismic data is divided into left arrangement and right arrangement according to different frequency components; Abnormal energy amplitude is suppressed for the left-arranged and right-arranged data respectively.

4. The method according to claim 3, wherein Suppression of abnormal energy amplitudes, including: According to the characteristics of the abnormal energy, it is transformed into the shot domain, receiver domain or common center point gather CMP domain for denoising.

5. The method according to claim 1, wherein Performing irregularly sampled linear noise suppression on the seismic data, comprising: The linear noise in the seismic data is suppressed by using irregular sampling technology.

6. The method according to claim 1, wherein Residual scattered surface waves in the seismic data are removed by using a multi-domain combination method, including: Transforming seismic data into multiple data domains; the data domains include: shot domain, receiver point domain, and common center point gather CMP domain; Find the linear law of the scattered surface waves and remove the linear interference by using KL transform or FK transform.

7. The method according to claim 1, wherein Removing multiply refracted signals from the seismic data includes: The first arrival is used to flatten the single shot and restore the linear characteristics of multiple refractions. The time window is opened and the horizontal phase axis of the time window below the first arrival is suppressed.

8. The method according to claim 1, wherein Suppressing shallow residual noise in the common offset vector cov domain of the seismic data includes: The seismic data is transformed into the cov domain, and the tilted event in the seismic data is suppressed according to the phase consistency of the cov domain, and then transformed into the shot domain.

9. A denoising device for mountain seismic data, characterized in that: include: The surface wave suppression module is used to suppress the surface waves and their scattered components in the original mountain seismic data using surface wave simulation technology; A partitioned multi-domain suppression module is used to partition the seismic data after surface wave suppression by different frequency components and suppress the amplitude of abnormal energy corresponding to different regions; An irregular sampling linear noise suppression module, configured to perform irregular sampling linear noise suppression on the seismic data; A multi-domain combination residual surface wave suppression module is used to remove residual scattered surface waves in the seismic data by using a multi-domain combination method; a refraction signal removal module, configured to remove multiply refracted signals in the seismic data; The shallow noise suppression module is used to suppress the shallow residual noise of the seismic data in the common offset vector cov domain.

10. A computing device, characterized in that include: A memory, a processor, and a computer program stored in the memory and executable on the processor, wherein when the processor executes the program, the method for denoising mountain seismic data according to any one of claims 1 to 8 is implemented.

11. A computer-readable storage medium, characterized in that The computer-readable storage medium stores a computer program, and when the computer program is executed by a processor, the method for denoising mountain seismic data according to any one of claims 1 to 8 is implemented.

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