Method and device for suppressing multiple waves of free surface in data of subsea nodes

Abstract

The present application relates to the technical field of seismic exploration, and provides a method and device for suppressing free surface multiple waves of seabed node data. The method comprises: interpolating upgoing wave and downgoing wave seabed node data; separating multiple waves according to the periodic characteristics of the wave field incidence angle variation; establishing a target function by using a sparse inversion method; and solving the upgoing wave field without free surface related multiple waves based on the target function by using a fast iterative shrinkage threshold to remove the free surface multiple waves. The present application can effectively remove the free surface multiple waves in the upgoing wave field of the seabed node data in the ultra-shallow water area, and significantly improve the primary wave imaging quality of seismic data.

Description

Technical Field

[0001] This invention relates to the field of seismic exploration technology, specifically to a method for suppressing free surface multiples of seabed node data, a device for suppressing free surface multiples of seabed node data, and a computer device. Background Technology

[0002] Compared with traditional narrow azimuth (NAZ) towed cable acquisition, seabed node (OBN) exploration has the advantages of flexible acquisition and construction, ultra-long offset reception, all-round, high coverage, repeatability and broadband, multi-component, and plays an important role in the exploration and development of complex marine oil and gas fields and reservoirs, and is gradually replacing towed cable acquisition.

[0003] In seabed node (OBN) data acquisition, three-component geophones (water-based and land-based) are embedded in the ocean floor to record pressure and velocity data. The water-based P-component geophone is a pressure detector and has no directionality; the land-based three-component geophone is a velocity detector and has directionality, including X, Y, and Z components, with the Z component perpendicular to the seabed to receive P-wave signals. Wavefield separation using the water-based P-component and the land-based Z-component allows for the classification of waves into ascending and descending waves. However, the ascending wavefield still contains numerous multiples associated with the free surface (sea surface), including shot ghost waves, water layer multiples, and free surface multiples associated with the reflector layer. These multiples severely affect the quality of exploration data, causing structural artifacts and increasing exploration risks; therefore, they must be removed during data processing.

[0004] Existing technologies employ uplink and downlink wavefield deconvolution, which can effectively remove free surface multiples in relatively deep (greater than 20 meters) and relatively flat seabed waters. However, in the processing of OBN data acquired in ultra-shallow waters (1-20 meters), the number of direct waves (downlink waves) is very small and is masked by strong energy noise. At the same time, the wavefield propagation distance is comparable to the size of the gun array, and the wavefield recorded by the seabed nodes is extremely complex. The uplink wave imaging accuracy of OBN data in ultra-shallow waters is severely affected by multiples, and existing uplink and downlink wavefield deconvolution techniques often fail to achieve ideal results. Summary of the Invention

[0005] To address the shortcomings of existing technologies, this invention provides a method for suppressing free surface multiples in seabed node data, which effectively removes free surface multiples in the upflow wave field of seabed node data in ultra-shallow waters.

[0006] This invention provides a method for suppressing free surface multiple waves in seabed node data, comprising:

[0007] Interpolate the seabed node data for upgoing and downgoing waves;

[0008] The multiple waves are separated according to the periodic characteristics of the change in the incident angle of the wave field;

[0009] The objective function is established using the sparse inversion method;

[0010] Based on the objective function, the rising wave field without free surface correlated multiples is solved by rapidly iterating and shrinking the threshold, so as to remove free surface multiples.

[0011] In this embodiment of the invention, the interpolation of the upgoing and downgoing wave seabed node data includes: using Fourier transform to perform high-density interpolation of the upgoing and downgoing wave seabed node data in the frequency-wavenumber domain.

[0012] In this embodiment of the invention, the sparsely spatially sampled wavefield is forward transformed from the sparse spatiotemporal domain to the FKK domain; relevant threshold values ​​are set, and effective information of the wavefield is extracted through iteration to perform high-density interpolation; the up-going wave and down-going wave are inversely transformed back to the high-density spatially sampled spatiotemporal domain.

[0013] In this embodiment of the invention, separating the multiple waves according to the periodic characteristics of the change in the incident angle of the wave field includes: performing a three-dimensional Taup transformation on the P component and Z component of the multiple waves respectively, and separating the multiple waves according to the periodic characteristics of the change in the incident angle of the wave field.

[0014] In this embodiment of the invention, the formula for the three-dimensional Taup transformation is:

[0015]

[0016] In the formula,

[0017] τ = t - px;

[0018]

[0019] Among them, V * Let θ represent the apparent velocity, θ represent the incident angle of the seismic wave ray, V represent the wave velocity in the medium, t represent the time-domain sample point, and P represent the velocity. x Sample the P value in the x-direction, P y The P-value is sampled in the y-direction, where the P-value represents the incident angle of the wave field.

[0020] In this embodiment of the invention, the objective function established using the sparse inversion method is:

[0021]

[0022] in,

[0023] U = D*r;

[0024] r i+1 =T τ [ri +D H (U-Dr i )];

[0025] U represents the ascending wave field, D represents the descending wave field, r is the subsurface reflection coefficient sequence, λ is the regularization parameter, and T... τ It is the transform domain threshold operator, where i refers to the i-th iteration.

[0026] In this embodiment of the invention, the free surface multiple suppression method for seabed node data further includes: inversely transforming the uphill wave field after multiple suppression back to the time domain to obtain the uphill wave field after time domain free surface correlated multiple attenuation.

[0027] In this embodiment of the invention, the up-wave field after multiple wave suppression is inversely transformed back to the time domain by the three-dimensional Taup inverse transform to obtain the time domain Vz noise model.

[0028] The formula for the three-dimensional Taup inverse transform is:

[0029]

[0030] Where t represents the time-domain sample point, and P x Sample the P value in the x-direction, P y The P-value is sampled in the y-direction, where the P-value represents the incident angle of the wave field.

[0031] Another aspect of the present invention provides a free surface multiple wave suppression device for seabed node data, comprising:

[0032] The interpolation module is used to interpolate seabed node data for upgoing and downgoing waves;

[0033] The multiple wave separation module is used to separate multiple waves according to the periodic characteristics of the wave field incident angle.

[0034] The multiple suppression module is used to establish an objective function using the sparse inversion method. Based on the objective function, the module solves for the up-wave field that does not contain free surface-related multiples by rapidly iterating and shrinking the threshold, thereby removing free surface multiples.

[0035] The present invention also provides a computer device, comprising: a memory, a processor, and a computer program, the computer program being stored in the memory and configured to be executed by the processor to implement the above-described method for suppressing free surface multiple waves of seabed node data.

[0036] This invention is based on a model where the subsurface reflection coefficient sequence of OBN data is equivalent to the upflow wavefield. After high-density interpolation of OBN data, the upflow and downflow wavefield information are comprehensively utilized in the high-precision three-dimensional TauP domain. A relevant objective function is established through sparse inversion method, and the upflow wavefield without free surface correlated multiples is solved by fast iterative shrinkage threshold method. This avoids the instability caused by signal division in traditional deconvolution algorithms, and can effectively remove free surface multiples in the upflow wavefield of ultra-shallow water OBN data, providing a real and reliable data foundation for geological research and reducing exploration risks.

[0037] Other features and advantages of the technical solution of the present invention will be described in detail in the following detailed embodiments section. Attached Figure Description

[0038] The accompanying drawings, which are included to provide a further understanding of the invention and form part of this invention, illustrate exemplary embodiments of the invention and are used to explain the invention, but do not constitute an undue limitation of the invention. In the drawings:

[0039] Figure 1 This is a flowchart of the free surface multiple wave suppression method for seabed node data provided in an embodiment of the present invention;

[0040] Figure 2 This is a schematic diagram of spatiotemporal domain multiples (left) and Taup domain multiples (right);

[0041] Figure 3 This is a schematic diagram of the gather before multiple wave attenuation (left) and the gather after multiple wave attenuation (right);

[0042] Figure 4 This is a schematic diagram of the superimposed profile before multiple wave attenuation;

[0043] Figure 5 This is a schematic diagram of the superimposed profile after multiple wave attenuation;

[0044] Figure 6 This is a comparison diagram of the cross-section after multiple wave attenuation using traditional wave suppression methods and the cross-section after multiple wave attenuation using the present invention.

[0045] Figure 7 This is a comparison chart showing the application effects of the multi-wave suppression method of this invention in actual production projects. Detailed Implementation

[0046] To make the technical solutions and advantages of the embodiments of the present invention clearer, the exemplary embodiments of the present invention will be further described in detail below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of the present invention, and not an exhaustive list of all embodiments. It should be noted that, unless otherwise specified, the embodiments and features in the embodiments of the present invention can be combined with each other.

[0047] In the description of this invention, it should be understood that the terms "center," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," and "outer," etc., indicating orientation or positional relationships based on the orientation or positional relationships shown in the accompanying drawings, are only for the convenience of describing the invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of the invention. Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this invention, "a plurality of" means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0048] As described in the background section, existing technologies employ uplink and downlink wavefield deconvolution, which can effectively remove free surface multiples in uplink wavefields in relatively deep (greater than 20 meters) and relatively flat seabed waters. However, in the processing of OBN data acquired in ultra-shallow waters (1-20 meters), the number of direct waves (downlink waves) is very small and is masked by strong energy noise. At the same time, the wavefield propagation distance is comparable to the size of the gun array, and the wavefield recorded by the seabed nodes is extremely complex. The uplink wave imaging accuracy of OBN data in ultra-shallow waters is severely affected by multiples, and existing uplink and downlink wavefield deconvolution techniques often fail to achieve ideal results.

[0049] This invention provides a method for suppressing free surface multiples in seafloor node data. Based on a model where the downflow wavefield convolution of OBN data is equivalent to the upflow wavefield, the method performs high-density interpolation on the OBN data and comprehensively utilizes the information from both the upflow and downflow wavefields in a high-precision three-dimensional TauP domain. A relevant objective function is established using a sparse inversion method, and the upflow wavefield without free surface multiples is solved using a fast iterative shrinkage threshold method. This avoids the instability caused by signal division in traditional deconvolution algorithms and can effectively remove free surface multiples from the upflow wavefield of OBN data in ultra-shallow waters, providing a reliable data foundation for geological research and reducing exploration risks.

[0050] Figure 1 This is a flowchart of a free surface multiple wave suppression method for seabed node data provided in an embodiment of the present invention. Figure 1 As shown, the free surface multiple wave suppression method for seabed node data provided in this embodiment includes the following steps:

[0051] S110, interpolates the upgoing and downgoing wave seabed node data;

[0052] S120 separates multiple waves according to the periodic characteristics of the wave field incident angle change;

[0053] S130, the objective function is established by sparse inversion method, and the up-wave field without free surface correlated multiples is solved by fast iteratively shrinking the threshold based on the objective function, so as to remove free surface multiples;

[0054] S140 transforms the upflow field after multiple wave suppression back into the time domain.

[0055] In step S110 above, Fourier transform is used to perform high-density interpolation of the upgoing wave and downgoing wave seabed node data in the frequency-wavenumber domain (FK domain), and both the upgoing wave field and the downgoing wave field are interpolated into high-density spatial samples (sampling interval less than or equal to 6.25 meters).

[0056] Specifically, the wavefield sampled in sparse space is forward transformed from the sparse spatiotemporal domain to the FKK domain, relevant threshold values ​​are set, and effective information of the wavefield is extracted iteratively. Then, it is inversely transformed back to the spatiotemporal domain sampled in high-density space to complete high-density interpolation processing. That is, forward transformation, high-density interpolation, and inverse transformation are performed on the upgoing and downgoing waves respectively. The formula for the forward transformation is as follows:

[0057]

[0058] The formula for the inverse transform is as follows:

[0059]

[0060] In the forward transform, x represents a sampling point in the time domain or a sampling point in the spatial domain, while in the inverse transform, k represents a sampling point in the frequency domain or a sampling point in the beam domain.

[0061] In step S120 above, the Taup transform is used to separate the multiple waves according to the periodic characteristics caused by the change in the incident angle of the wave field. Specifically, this includes performing a three-dimensional Taup transform on the P component and Z component of the multiple waves respectively. Taking the two-dimensional Taup transform as an example, the formula is:

[0062]

[0063] In equation (3),

[0064] τ=t-px; (4)

[0065]

[0066] Among them, V * θ represents the apparent velocity, θ represents the incident angle of the seismic wave rays, and V represents the wave velocity in the medium;

[0067] Extending to the three-dimensional Taup transformation, its formula is:

[0068]

[0069] In equation (6),

[0070] τ = t - px;

[0071]

[0072] Among them, V * Let θ represent the apparent velocity, θ represent the incident angle of the seismic wave ray, V represent the wave velocity in the medium, t represent the time-domain sample point, and P represent the velocity. x Sample the P value in the x-direction, P y The P-value is sampled in the y-direction, where the P-value represents the incident angle of the wave field.

[0073] In step S130 above, a sparse inversion method is used in the three-dimensional Taup domain to establish a relevant objective function. The up-wave field, which does not contain free surface correlated multiples, is solved by rapidly iterating and shrinking the threshold, effectively avoiding the instability caused by signal division in traditional up- and down-wave field deconvolution algorithms. The objective function established using the sparse inversion method is:

[0074] U = D*r; (7)

[0075]

[0076] r i+1 =T τ [r i +D H (U-Dr i (9)

[0077] Equation (7) is derived from the model that the subsurface reflection coefficient sequence of the downlink wavefield convolution of OBN data is equivalent to the uplink wavefield, where U represents the uplink wavefield, D represents the downlink wavefield, and r is the subsurface reflection coefficient sequence; from Equation (7), it can be derived that:

[0078] Equation (8) is the objective function, and λ is the regularization parameter;

[0079] In equation (9), T τ It is the transform domain threshold operator, where i refers to the i-th iteration.

[0080] In step S140 above, the uphill wave field after multiple suppression is inversely transformed back to the time domain using a three-dimensional Taup inverse transform to obtain the time-domain Vz noise model, thereby obtaining the uphill wave field after attenuation of correlated multiples on the free surface in the time domain. The formula for the three-dimensional Taup inverse transform is:

[0081]

[0082] In equation (10), t represents the time-domain sample point, and P x Sample the P value in the x-direction, P y The P-value is sampled in the y-direction, where the P-value represents the incident angle of the wave field.

[0083] In a specific application scenario, the Taup transform is used to separate multiple waves according to the incident angle of the wave field, such as... Figure 2 As shown, the left part represents spatiotemporal multiples, and the right part represents Taupe multiples. The test results based on theoretical data are as follows: Figure 3 As shown, the left part is the gather before multiple attenuation, and the right part is the gather after multiple attenuation. The stacking profile before multiple attenuation is as follows. Figure 4 As shown, the superimposed profile after multiple wave attenuation is as follows: Figure 5 As shown, from Figure 4 and Figure 5 The comparison shows that the imaging effect after multiple wave attenuation is better. Based on actual data, a comparison of the test results of the traditional multiple wave suppression method and the multiple wave suppression method of this invention is shown below. Figure 6 As shown in the figure, the left part is the cross-section after multiple wave attenuation using the traditional wave suppression method, and the right part is the cross-section after multiple wave attenuation using the present invention. In an actual production project, the application effect of the multiple wave suppression method of the present invention is compared to... Figure 7 As shown, the upper part of the figure is the cross-section before multiple attenuation, and the lower part is the cross-section after multiple attenuation. Figure 7 It can be seen that the imaging effect is better after multiple wave attenuation.

[0084] After using the method provided in the above embodiments for multiple wave suppression, all relevant multiple wave noise caused by the strongly reflected sea surface is effectively attenuated, significantly improving the quality of primary wave imaging of seismic data, obtaining processing results that can accurately reflect the underground geological conditions, providing a high-fidelity data basis for interpreting well location, effectively improving drilling success rate, and reducing exploration risk.

[0085] This invention also provides a device for suppressing free surface multiples in seabed node data, comprising: an interpolation module, a multiple separation module, and a multiple suppression module. The interpolation module is used to interpolate upgoing and downgoing wave seabed node data. The multiple separation module is used to separate multiples according to the periodic characteristics of the wave field incident angle variation. The multiple suppression module is used to establish an objective function using a sparse inversion method, and based on the objective function, to solve for the upgoing wave field that does not contain free surface-related multiples by rapidly iterating and shrinking the threshold, thereby removing free surface multiples.

[0086] In one embodiment, the interpolation module uses Fourier transform to perform high-density interpolation of upgoing and downgoing wave seabed node data in the frequency-wavenumber domain (FK domain), interpolating both the upgoing and downgoing wave fields into high-density spatial samples (sampling interval less than or equal to 6.25 meters).

[0087] Specifically, the wavefield sampled in sparse space is forward transformed from the sparse spatiotemporal domain to the FKK domain, relevant threshold values ​​are set, and effective information of the wavefield is extracted iteratively. Then, it is inversely transformed back to the spatiotemporal domain sampled in high-density space to complete high-density interpolation processing. That is, forward transformation, high-density interpolation, and inverse transformation are performed on the upgoing and downgoing waves respectively. The formula for the forward transformation is as follows:

[0088]

[0089] The formula for the inverse transform is as follows:

[0090]

[0091] In the forward transform, x represents a sampling point in the time domain or a sampling point in the spatial domain, while in the inverse transform, k represents a sampling point in the frequency domain or a sampling point in the beam domain.

[0092] In one embodiment, the multiple separation module uses Taup transform to separate the multiples according to the periodic characteristics caused by the change in the incident angle of the wave field. Specifically, this includes performing a three-dimensional Taup transform on the P-component and Z-component of the multiples respectively, with the following formula:

[0093]

[0094] In equation (6),

[0095] τ = t - px;

[0096]

[0097] Among them, V * Let θ represent the apparent velocity, θ represent the incident angle of the seismic wave ray, V represent the wave velocity in the medium, t represent the time-domain sample point, and P represent the velocity. x Sample the P value in the x-direction, P yThe P-value is sampled in the y-direction, where the P-value represents the incident angle of the wave field.

[0098] In one embodiment, the multiple suppression module employs a sparse inversion method in the three-dimensional Taup domain to establish a relevant objective function. It then solves for the upgoing wave field without free surface-related multiples by rapidly iterating and shrinking the threshold, effectively avoiding the instability caused by signal division in traditional upgoing and downgoing wave field deconvolution algorithms. The objective function established using the sparse inversion method is:

[0099] U = D*r; (7)

[0100]

[0101] r i+1 =T τ [r i +D H (U-Dr i (9)

[0102] Equation (7) is derived from the model that the subsurface reflection coefficient sequence of the downlink wavefield convolution of OBN data is equivalent to the uplink wavefield, where U represents the uplink wavefield, D represents the downlink wavefield, and r is the subsurface reflection coefficient sequence; from Equation (7), it can be derived that:

[0103] Equation (8) is the objective function, and λ is the regularization parameter;

[0104] In equation (9), T τ It is the transform domain threshold operator, where i refers to the i-th iteration.

[0105] The ascending wave field after multiple suppression is inversely transformed back to the time domain using the three-dimensional Taup inverse transform to obtain the time-domain Vz noise model, thus obtaining the ascending wave field after attenuation of correlated multiples on the free surface in the time domain. The formula for the three-dimensional Taup inverse transform is:

[0106]

[0107] In equation (10), t represents the time-domain sample point, and P x Sample the P value in the x-direction, P y The P-value is sampled in the y-direction, where the P-value represents the incident angle of the wave field.

[0108] The present invention also provides a computer device, including: a memory, a processor, and a computer program, the computer program being stored in the memory and configured to be executed by the processor to implement the above-described method for suppressing free surface multiple waves of seabed node data.

[0109] Those skilled in the art will understand that embodiments of the present invention can be provided as methods, systems, or computer program products. Therefore, the present invention can take the form of a completely hardware embodiment, a completely software embodiment, or an embodiment combining software and hardware aspects. Furthermore, the present invention can take the form of a computer program product implemented on one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) containing computer-usable program code. The solutions in the embodiments of the present invention can be implemented using various computer languages, such as the object-oriented programming language Java and the interpreted scripting language JavaScript.

[0110] This invention is described with reference to flowchart illustrations and / or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of the invention. It will be understood that each block of the flowchart illustrations and / or block diagrams, and combinations of blocks in the flowchart illustrations 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, special-purpose computer, embedded processor, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, generate instructions for implementing the flowchart illustrations and / or block diagrams. Figure 1 One or more processes and / or boxes Figure 1 A device that provides the functions specified in one or more boxes.

[0111] These computer program instructions may also be stored in a computer-readable storage medium that can direct a computer or other programmable data processing device to function in a particular manner, such that the instructions stored in the computer-readable storage medium produce an article of manufacture including instruction means, which are implemented in a process Figure 1 One or more processes and / or boxes Figure 1 The functions specified in one or more boxes. These computer program instructions may also be loaded onto a computer or other programmable data processing apparatus to cause a series of operational steps to be performed on the computer or other programmable apparatus to produce a computer-implemented process, thereby providing instructions that execute on the computer or other programmable apparatus for implementing the process. Figure 1 One or more processes and / or boxes Figure 1 The steps of the function specified in one or more boxes.

[0112] Although preferred embodiments of the invention have been described, those skilled in the art, upon learning the basic inventive concept, can make other changes and modifications to these embodiments. Therefore, the appended claims are intended to be interpreted as including both the preferred embodiments and all changes and modifications falling within the scope of the invention. Clearly, those skilled in the art can make various alterations and modifications to the invention without departing from its spirit and scope. Thus, if these modifications and modifications of the invention fall within the scope of the claims and their equivalents, the invention is also intended to include these modifications and modifications.

Claims

1. A method for suppressing free-surface multiple waves from seabed node data, characterized in that, include: Interpolate the seabed node data for upgoing and downgoing waves; After interpolation is completed, the multiple waves are separated according to the periodic characteristics of the change in the incident angle of the wave field; After separating multiple waves, the objective function is established using the sparse inversion method; Based on the objective function, the rising wave field without free surface correlated multiples is solved by rapidly iterating and shrinking the threshold, so as to remove free surface multiples; The objective function is: ;in, ； ； Describe the objective function. Indicates the upward wave field. Indicates the downlink wave field. It is a sequence of underground reflection coefficients. Indicates the downlink wave field With underground reflection coefficient sequence folding, It is a regularization parameter. It is the first iteration , They are the first The next iteration, the... The sequence of underground reflection coefficients in the next iteration. Indicates the downlink wave field The conjugate transpose of the matrix. Indicates the first The downlink wave field of the next iteration, It is a transform domain threshold operator.

2. The method for suppressing free-surface multiple waves of seabed node data according to claim 1, characterized in that, The interpolation of upgoing and downgoing wave seabed node data includes: High-density interpolation of upgoing and downgoing wave seabed node data in the frequency-wavenumber domain is performed using Fourier transform.

3. The method for suppressing free-surface multiple waves of seabed node data according to claim 2, characterized in that, The method of using Fourier transform to perform high-density interpolation of seabed node data for upgoing and downgoing waves in the frequency-wavenumber domain includes: Transform the wave field sampled in sparse space from the sparse spatiotemporal domain to the FKK domain; Set relevant threshold values, extract effective information of the wave field through iterative methods, and perform high-density interpolation; The upward and downward waves are inversely transformed back to the spatiotemporal domain of high-density spatial sampling.

4. The method for suppressing free-surface multiple waves of seabed node data according to claim 1, characterized in that, The separation of multiple waves according to the periodic characteristics of the change in the incident angle of the wave field includes: A three-dimensional Taup transformation is performed on the P and Z components of the multiple waves to separate the multiple waves according to the periodic characteristics of the wave field incident angle.

5. The method for suppressing free-surface multiple waves of seabed node data according to claim 4, characterized in that, The formula for the three-dimensional Taup transformation is: ； In the formula, ； ； in, Indicates apparent speed. θ Indicates the angle of incidence of seismic wave rays. V Indicates the wave velocity in the medium. t For time domain samples, for x P-value sampling in the direction, The P-value is sampled in the y-direction, where the P-value represents the incident angle of the wave field.

6. The method for suppressing free-surface multiple waves of seabed node data according to claim 1, characterized in that, The method further includes: The upflow field after multiple wave suppression is transformed back to the time domain to obtain the upflow field after time-domain free surface correlation multiple wave attenuation.

7. The method for suppressing free-surface multiple waves of seabed node data according to claim 6, characterized in that, The process of transforming the upflow field after multiple wave suppression back to the time domain includes: The up-wave field after multiple wave suppression is inversely transformed back to the time domain by the three-dimensional Taup inverse transform to obtain the time domain Vz noise model. The formula for the three-dimensional Taup inverse transform is: ； in, t For time domain samples, for x P-value sampling in the direction, The P-value is sampled in the y-direction, where the P-value represents the incident angle of the wave field.

8. A device for suppressing free-surface multiple waves of seabed node data, characterized in that, include: The interpolation module is used to interpolate seabed node data for upgoing and downgoing waves; The multiple wave separation module is used to separate multiple waves according to the periodic characteristics of the wave field incident angle after interpolation is completed; The multiple suppression module is used to establish an objective function after separating multiples using a sparse inversion method. Based on the objective function, the up-wave field that does not contain free surface-related multiples is solved by rapidly iterating and shrinking the threshold, so as to remove free surface multiples. The objective function is: ;in, ； ； Describe the objective function. Indicates the upward wave field. Indicates the downlink wave field. It is a sequence of underground reflection coefficients. Indicates the downlink wave field With underground reflection coefficient sequence folding, It is a regularization parameter. It is the first iteration , They are the first The next iteration, the... The sequence of underground reflection coefficients in the next iteration. Indicates the downlink wave field The conjugate transpose of the matrix. Indicates the first The downlink wave field of the next iteration, It is a transform domain threshold operator.

9. A computer device, characterized in that, include: Memory; processor; as well as Computer programs; The computer program is stored in a memory and configured to be executed by a processor to implement the seabed node data free surface multiple wave suppression method according to any one of claims 1-7.

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