Method and device for suppressing multiple waves on land surface

Abstract

The invention discloses a land surface multiple suppression method and device, and belongs to the technical field of oil exploration. According to the method, data of static correction values of shot points and detection points for reaction are used as SRME input data, and internal interpolation processing time difference correction is carried out by using the total static correction value of the shot points and the detection points, so that the undulating surface multiple prediction is carried out. According to the land surface multiple suppression method and device provided by the invention, the shot point and the detection point are placed on the real ground surface by reflecting the static correction values of the shot point and the detection point, the real travel of the seismic wave is recovered, and the total static correction value of the shot point and the detection point is interpolated and encrypted and is applied to SRME internal regularization, so that the real travel of the seismic wave is recovered. The method improves the precision of the surface multiple prediction model, achieves the purpose of better suppressing the surface multiple, and is suitable for suppressing the surface multiple of the undulating surface.

Description

Technical Field

[0001] The invention belongs to the technical field of petroleum exploration, and relates to a surface multiple wave suppression method, in particular to a land surface multiple wave suppression method and device. Background Art

[0002] Surface multiple waves exist not only in marine seismic data, but also widely develop in land seismic data. Surface multiple waves seriously reduce the quality of seismic data and are a major problem faced in seismic data processing. Currently, SRME technology is usually used to suppress surface multiple waves.

[0003] SRME technology is a method that uses seismic data itself to predict surface-related multiple waves through two-dimensional convolution in the time and space domain, and subtracts the predicted multiple waves through adaptive subtraction to achieve surface-related multiple wave suppression. SRME technology was first applied to marine streamer data. It assumes that the shot point and the receiver point are on the same horizontal plane. In this way, when performing internal regularization, the time difference between the target channel and the borrowed seismic channel is mainly the dynamic correction time difference caused by the difference in shot offset, which can be corrected by calculating the dynamic correction time difference through velocity. However, due to the surface undulation or near-surface velocity changes of land seismic data, this condition cannot be met. The current solution is to first apply the data to a smooth CMP reference surface and then predict surface multiple waves. This approach overcomes the above problems, but the application of high-frequency static correction destroys the true travel time relationship. There is a large error between the predicted surface multiple waves and the reflection time of the surface multiple waves in the data. This time difference is difficult to completely solve through subsequent adaptive subtraction, which affects the suppression effect of surface multiple waves. Summary of the invention

[0004] The purpose of the present invention is to provide a method and device for suppressing multiple waves on the land surface, so as to solve the problems of low prediction accuracy and poor suppression effect of multiple waves on the surface of land seismic data.

[0005] In order to achieve the above object, the technical solution adopted by the present invention is: A land surface multiple wave suppression method uses the static correction data of the response shot points and receiver points as SRME input data, uses the total static correction data of the shot points and receiver points to perform internal interpolation processing and time difference correction, and thus predicts surface multiple waves.

[0006] As a limitation, the following steps are included: S1. After the seismic data is processed by static correction and noise suppression, the static correction value is used to form a gather; S2. The total static correction values ​​of the shot points and the receiver points are combined, interpolated and encrypted, and together with the coordinates of the shot points and the receiver points, form a total static correction value library of the shot points and the receiver points; S3. Input the gathers and total static correction database, use SRME to predict surface multiple waves, and form a surface multiple wave model; The total static correction database is used for internal regularized time difference correction; S4. After the seismic data is processed by static correction and noise suppression, the surface multiple wave model is adaptively subtracted after static correction to obtain the seismic data with suppressed surface multiple waves.

[0007] As a further limitation, the static correction includes a reference surface static correction and a surface consistency residual static correction; and the static correction amount includes a reference surface static correction amount and a surface consistency residual static correction amount.

[0008] As a further limitation, the total static correction is the accumulation of the reference surface static correction and the surface consistency residual static correction.

[0009] The present invention also provides a land surface multiple wave suppression device, comprising: The seismic data processing module is used to convert the seismic data after static correction and noise suppression into static correction values ​​to form a gather; A total static correction value library acquisition module is used to merge, interpolate and encrypt the total static correction values ​​of the shot point and the detection point, and form a total static correction value library of the shot point and the detection point together with the coordinates of the shot point and the detection point; The surface multiple wave model acquisition module is used to input the gathers and the total static correction library, use SRME to predict the surface multiple waves, and form the surface multiple wave model; The surface multiple wave suppression module is used to adaptively subtract the statically corrected seismic data from the surface multiple wave model to obtain seismic data with suppressed surface multiple waves.

[0010] Due to the adoption of the above technical solution, the present invention has the following technical advances compared with the prior art: The present invention provides a method and device for suppressing multiple waves on the land surface. The method and device use the static correction values ​​of shot points and receiver points to place the shot points and receiver points on the real ground surface, restore the real travel time of seismic waves, and interpolate and encrypt the total static correction values ​​of the shot points and receiver points and apply them to the internal regularization of SRME, thereby improving the accuracy of the surface multiple wave prediction model, thereby achieving the purpose of better suppressing surface multiple waves. The method and device are suitable for suppressing surface multiple waves on undulating surfaces. BRIEF DESCRIPTION OF THE DRAWINGS

[0011] Figure 1 It is a flowchart in the embodiment, wherein: Figure 1 a is the flowchart of the current land surface multiple wave suppression scheme. Figure 1 b is a flowchart of the technical solution of the present invention; Figure 2This is a diagram of the forward simulation data preprocessing results in the embodiment, where: Figure 2 a is the input forward simulation data, Figure 2 b is the data after static correction and noise suppression processing, Figure 2 c is the data of static correction for reaction; Figure 3 is the total static correction curve in the embodiment, where: Figure 3 a is the total static correction curve of the shot point, Figure 3 b is the total static correction curve of the detection point, Figure 3 c is the total static correction curve after interpolation and encryption; Figure 4 is the surface multiple wave model predicted by SRME in the embodiment; Figure 5 The static correction processing result of the surface multiple wave model in the embodiment is applied; Figure 6 This is the result of suppressing surface multiple waves in the embodiment; Figure 7 This is a comparison of the surface multiple wave models predicted by the two schemes in the embodiment, where: Figure 7 a and Figure 7 b are the input data of the current land surface multiple wave suppression scheme and the predicted surface multiple wave model, Figure 7 c and Figure 7 d are respectively the input data of the technical solution of the present invention and the predicted surface multiple wave model. DETAILED DESCRIPTION

[0012] The present invention is further described in detail below by specific examples. It should be understood that the described examples are only used to explain the present invention, and are not intended to limit the present invention.

[0013] Embodiment A method and device for suppressing multiple waves on land surface This embodiment provides a land surface multiple wave suppression method, which is tested by applying forward modeling data of undulating surface. Figure 1 b, and is consistent with the current land surface multiple wave suppression scheme (flow chart as shown in Figure 1 a) was compared with Figure 1 It can be seen that the technical solution of the present invention is significantly different from the prior art in terms of the processing method flow. The specific operation steps of the technical solution of the present invention are as follows: S1. The forward modeling data of the undulating surface (such as Figure 2 a) to perform datum static correction, surface consistency residual static correction and noise suppression iterative processing, focusing on suppressing the first arrival wave interference. The data processing results are shown in Figure 2 As shown in b; S2. Use the reference static correction of the shot point and the residual static correction of the surface consistency to restore the shot point to the surface. Use the reference static correction of the receiver point and the residual static correction of the surface consistency to restore the receiver point to the surface to form a gather. The data processing results are as follows: Figure 2 As shown in c; S3. The reference surface static correction amount and the residual static correction amount of the surface consistency of the shot point are accumulated together to form the total static correction amount of the shot point, and the reference surface static correction amount and the residual static correction amount of the surface consistency of the detection point are accumulated together to form the total static correction amount of the detection point; S4. Combine the total static correction values ​​of the shot points and the receiver points, interpolate and encrypt them, and the grid is a plane of the processing surface element size (the total static correction curve is as follows Figure 3 As shown in the figure), the coordinates of the shot points and the receiver points are put into the database to form the total static correction database of the shot points and the receiver points; S5. Input the gathers formed in step S2, call the total static correction library formed in step S4, and use SRME to predict surface multiple waves, where the total static correction library is used for internal regularized time difference correction to form a surface multiple wave model, such as Figure 4 As shown; S6. The surface multiple wave model formed in step S5 applies the base surface static corrections of the shot points and the receiver points and the surface consistency residual static corrections to the CMP reference surface, such as Figure 5 As shown; S7. The seismic data processed in step S1 and the surface multiple wave model processed in step S6 are selected as shot gather data for adaptive subtraction, so as to obtain seismic data with suppressed surface multiple waves, such as Figure 6 shown.

[0014] According to the current land surface multiple wave suppression scheme (flow chart as shown in Figure 1 a) and the technical solution of the present invention (flow chart as shown in Figure 1 b) respectively process the forward modeling data of the undulating surface, and the processing results are as follows Figure 7 As shown, the figure shows the common offset section; Depend on Figure 7 By comparison, it can be seen that the surface multiple wave model predicted by the technical solution of the present invention is consistent with the multiple wave time in the forward simulation data, and the morphology is basically the same; while the surface multiple wave model predicted by the current land surface multiple wave suppression scheme is very different from the forward simulation data at locations with large surface undulations.

[0015] This embodiment also provides a land surface multiple wave suppression device, comprising: A seismic data processing module, used to apply static correction values ​​to seismic data after static correction and noise suppression to form a gather; A total static correction value library acquisition module is used to merge, interpolate and encrypt the total static correction values ​​of the shot point and the receiver point, and form a total static correction value library together with the coordinates of the shot point and the receiver point; The surface multiple wave model acquisition module is used to input the gathers and the total static correction library, use SRME to predict the surface multiple waves, and form the surface multiple wave model; The surface multiple wave suppression module is used to adaptively subtract the statically corrected seismic data from the surface multiple wave model to obtain seismic data with suppressed surface multiple waves.

Claims

1. A land surface multiple wave suppression method, characterized in that: It uses the static correction data of shot points and receiver points as SRME input data, and uses the total static correction of shot points and receiver points to perform time difference correction, thereby predicting surface multiple waves.

2. A land surface multiple wave suppression method according to claim 1, characterized in that: The following steps are involved: S1. After the seismic data is processed by static correction and noise suppression, the static correction value is used to form a gather; S2. The total static correction values ​​of the shot points and the receiver points are combined, interpolated and encrypted, and together with the coordinates of the shot points and the receiver points, form a total static correction value library of the shot points and the receiver points; S3. Input the gathers and total static correction database, use SRME to predict surface multiple waves, and form a surface multiple wave model; The total static correction database is used for internal regularized time difference correction; S4. After the seismic data is processed by static correction and noise suppression, the surface multiple wave model is adaptively subtracted after static correction to obtain the seismic data with suppressed surface multiple waves.

3. A land surface multiple wave suppression method according to claim 2, characterized in that: The static correction includes reference surface static correction and surface consistency residual static correction; the static correction amount includes reference surface static correction amount and surface consistency residual static correction amount.

4. A land surface multiple wave suppression method according to claim 2 or 3, characterized in that: The total static correction is the sum of the reference surface static correction and the surface consistency residual static correction.

5. A land surface multiple wave suppression device, characterized in that: include: The seismic data processing module is used to convert the seismic data after static correction and noise suppression into static correction values ​​to form a gather; A total static correction value library acquisition module is used to merge, interpolate and encrypt the total static correction values ​​of the shot point and the detection point, and form a total static correction value library of the shot point and the detection point together with the coordinates of the shot point and the detection point; The surface multiple wave model acquisition module is used to input the gathers and the total static correction library, use SRME to predict the surface multiple waves, and form the surface multiple wave model; The surface multiple wave suppression module is used to adaptively subtract the statically corrected seismic data from the surface multiple wave model to obtain seismic data with suppressed surface multiple waves.

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