Diffraction Wave Separation Method and Device under Uneven Spatiotemporal Sampling

Abstract

The present invention provides a diffraction wave separation method and device under non-uniform spatio-temporal sampling, which relates to the technical field of seismic exploration. The method includes: acquiring common-offset seismic data of a target area, where the common-offset seismic data includes wave signals of multiple sampling points, and among them, the position intervals between sampling points of different seismic traces are non-uniform, and / or the time intervals between different sampling points of the same seismic trace are non-uniform; calculating the plane wave slope of each sampling point of the common-offset seismic data by using the finite difference method to obtain plane wave slope data; determining the reflection wave travel time curve of each sampling point according to the plane wave slope data; and separating the diffraction waves of the common-offset seismic data according to the reflection wave travel time curves of each sampling point. The present invention realizes accurate separation of diffraction waves under non-uniform spatio-temporal sampling and improves the accuracy of seismic data analysis.

Description

Technical Field

[0001] The present invention relates to the technical field of seismic exploration, and in particular, to a diffraction wave separation method and device under uneven spatio-temporal sampling. 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 a small scale do not have a continuous reflection interface and do not generate reflected waves, but form diffraction waves as secondary seismic sources. Therefore, seismic diffraction 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 diffraction waves is one to two orders of magnitude lower than that of reflected waves, and they will be shielded by strong reflected wave signals, unable to exert their high-resolution detection potential. Therefore, it is necessary to separate the diffraction waves, eliminate the shielding effect of the reflected waves, and achieve high-resolution detection of the diffraction waves. The optimal local dip calculation method based on plane wave decomposition is a relatively effective diffraction wave separation method at present. However, this method assumes that seismic data is uniformly sampled in space and time, and it is unable to accurately predict the local dip of the reflected waves under uneven spatio-temporal sampling, making it difficult to accurately predict the reflected waves and separate the diffraction waves. Summary of the Invention

[0004] The purpose of the present invention is to provide a diffraction wave separation method and device under uneven spatio-temporal sampling to achieve the separation of diffraction waves under uneven spatio-temporal sampling.

[0005] In a first aspect, the present invention provides a diffraction wave separation method under uneven spatio-temporal sampling, including:

[0006] Obtaining common-offset seismic data of a target area, where the common-offset seismic data includes fluctuation signals of multiple sampling points, and the position intervals between the sampling points of different seismic traces are uneven, and / or the time intervals between different sampling points of the same seismic trace are uneven;

[0007] Calculating the plane wave slope of each sampling point of the common-offset seismic data by using the finite difference method to obtain plane wave slope data;

[0008] Determining the travel-time curve of the reflected wave at each sampling point according to the plane wave slope data;

[0009] Separating the diffraction waves of the common-offset seismic data according to the travel-time curves of the reflected waves at each sampling point.

[0010] In an alternative embodiment, the step of calculating the plane wave slope of each sampling point from the common offset seismic data by the finite difference method to obtain the plane wave slope data includes:

[0011] Calculating the spatial difference value and the time difference value of each sampling point based on the fluctuation signals of each sampling point and its adjacent points; wherein, the adjacent points include the sampling points of adjacent seismic traces at the same sampling time and the sampling points of adjacent sampling times on the same seismic trace;

[0012] Calculating the plane wave slope of each sampling point based on the spatial difference value and the time difference value of each sampling point.

[0013] In an alternative embodiment, the spatial difference value is calculated by the following formula:

[0014] ;

[0015] The time difference value is calculated by the following formula:

[0016] ;

[0017] The plane wave slope a is calculated by the following formula:

[0018] ;

[0019] wherein, P ( m ) represents the fluctuation signal at position m , P ( m- ) represents the fluctuation signal at position m- , P ( m+ ) represents the fluctuation signal at position m+ , , respectively represent the position intervals between the seismic trace to which the current sampling point belongs and the previous seismic trace and the next seismic trace, P ( t ) represents the fluctuation signal at sampling time t , P ( t- ) represents the fluctuation signal at sampling time t- , P ( t+ )Indicates the sampling time t+ The fluctuating signal under 、 respectively represent the time intervals between the sampling time of the current sampling point and the previous sampling time and the next sampling time.

[0020] In an alternative embodiment, the step of determining the travel-time curve of the reflected wave for each sampling point according to the plane-wave slope data includes:

[0021] Calculating the intercept in the travel-time curve of the reflected wave for each sampling point according to the position, sampling time, and plane-wave slope of each sampling point;

[0022] Determining the travel-time curve of the reflected wave for each sampling point according to the plane-wave slope and intercept of each sampling point.

[0023] In an alternative embodiment, the intercept b is calculated by the following formula:

[0024] ;

[0025] where t represents the sampling time, a represents the plane-wave slope, m represents the position of the seismic trace to which it belongs.

[0026] In an alternative embodiment, the step of separating diffracted waves from common-offset seismic data according to the travel-time curves of the reflected waves at each sampling point includes:

[0027] Determining the corresponding reflected-wave signal in the common-offset seismic data according to the travel-time curve of the reflected wave at each sampling point;

[0028] Determining the diffracted-wave signal at each sampling point as the difference between the fluctuating signal and the reflected-wave signal at each sampling point.

[0029] In an alternative embodiment, the reflected-wave signal is calculated by the following formula:

[0030] ;

[0031] where represents the reflected-wave signal at position m , sampling time t under, k represents the number of seismic traces within a given spatial window, represents the fluctuating signal at position m + , sampling time under, represents the within the spatial windowi The distance between an earthquake trace and m a and b respectively represent the plane wave slope and intercept in the reflection wave travel time curve.

[0032] In a second aspect, the present invention provides a diffraction wave separation device under non-uniform spatio-temporal sampling, including:

[0033] An acquisition module for acquiring common-offset seismic data of a target area, the common-offset seismic data including fluctuation signals of a plurality of sampling points, wherein the position intervals between the sampling points of different seismic traces are non-uniform, and / or the time intervals between different sampling points of the same seismic trace are non-uniform;

[0034] A calculation module for calculating the plane wave slope of each sampling point of the common-offset seismic data by the finite difference method to obtain plane wave slope data;

[0035] A determination module for determining the reflection wave travel time curve of each sampling point according to the plane wave slope data;

[0036] A separation module for separating the diffraction waves of the common-offset seismic data according to the reflection wave travel time curves of the respective sampling points.

[0037] In a third aspect, the present invention provides an electronic device, including a memory and a processor, where a computer program executable on the processor is stored in the memory, and when the processor executes the computer program, it implements the diffraction wave separation method under non-uniform spatio-temporal sampling in any one of the foregoing embodiments.

[0038] In a fourth aspect, the present invention provides a computer-readable storage medium, on which a computer program is stored, and when the computer program is run by a processor, it executes the diffraction wave separation method under non-uniform spatio-temporal sampling in any one of the foregoing embodiments.

[0039] The diffraction wave separation method and device under non-uniform spatio-temporal sampling provided by the present invention can acquire common-offset seismic data of a target area, the common-offset seismic data including fluctuation signals of a plurality of sampling points, wherein the position intervals between the sampling points of different seismic traces are non-uniform, and / or the time intervals between different sampling points of the same seismic trace are non-uniform; calculate the plane wave slope of each sampling point of the common-offset seismic data by the finite difference method to obtain plane wave slope data; determine the reflection wave travel time curve of each sampling point according to the plane wave slope data; and separate the diffraction waves of the common-offset seismic data according to the reflection wave travel time curves of the respective sampling points. In this way, the diffraction wave separation under non-uniform spatio-temporal sampling is realized by using the finite difference method. Description of the Drawings

[0040] 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 accompanying drawings required for the description of the specific embodiments or the prior art. Obviously, the accompanying drawings in the following description are some embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other accompanying drawings can also be obtained based on these drawings.

[0041] Figure 1 It is a schematic flow chart of a diffraction wave separation method under uneven spatio-temporal sampling provided by an embodiment of the present invention;

[0042] Figure 2 It is a schematic flow chart of another diffraction wave separation method under uneven spatio-temporal sampling provided by an embodiment of the present invention;

[0043] Figure 3 It is a schematic structural diagram of a diffraction wave separation device under uneven spatio-temporal sampling provided by an embodiment of the present invention;

[0044] Figure 4 It is a schematic structural diagram of an electronic device provided by an embodiment of the present invention. Specific Embodiments

[0045] The following will clearly and completely describe the technical solutions of the present invention in conjunction with the embodiments. Obviously, the described embodiments are some, but not all, of the embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts belong to the scope of protection of the present invention.

[0046] The optimal local dip calculation method based on plane wave decomposition is a relatively effective diffraction wave separation method at present. However, this method assumes that seismic data is uniformly sampled in space and time. It is difficult to accurately predict reflected waves under uneven spatio-temporal sampling, and thus it is difficult to achieve diffraction wave separation in this case. The inventor found that the local dip in the plane wave equation can be obtained by finite difference method. In this case, the information of uneven sampling intervals can be introduced to estimate the local dip, so as to calculate the travel time curve of the reflected wave and complete the diffraction wave separation goal. Based on this, an uneven spatio-temporal sampling diffraction wave separation method and device provided by the embodiments of the present invention propose a reflected wave travel time curve calculation strategy based on the finite difference method for uneven spatio-temporal sampling conditions, which can be used for diffraction wave separation under uneven spatio-temporal sampling, effectively solve the diffraction wave separation problem under uneven spatio-temporal sampling, and accurately locate geological discontinuities such as faults and collapse columns. The embodiments of the present invention have the ability to obtain weak signals of seismic diffraction waves and can serve for the detection of small-scale geological anomalies in seismic exploration.

[0047] To facilitate the understanding of this embodiment, a diffraction wave separation method under non-uniform spatio-temporal sampling disclosed in the embodiments of the present invention will be introduced in detail first.

[0048] The embodiments of the present invention provide a diffraction wave separation method under non-uniform spatio-temporal sampling, which can be executed by an electronic device with data processing capabilities. The embodiments of the present invention propose an effective diffraction wave separation method under non-uniform spatio-temporal sampling. This method uses the finite difference method to calculate the slope of the reflection wave isochrone, and then obtains the intercept and the reflection wave travel time curve. Using this travel time curve, the reflection wave travel time at any position can be calculated, and finally the separation of the reflection wave and the diffraction wave is achieved.

[0049] See Figure 1 the schematic flow chart of a diffraction wave separation method under non-uniform spatio-temporal sampling shown in

[0050] Step S110: Obtain the common offset seismic data of the target area. The common offset seismic data includes the fluctuation signals of multiple sampling points. Among them, the position intervals between the sampling points of different seismic traces are non-uniform, and / or the time intervals between different sampling points of the same seismic trace are non-uniform.

[0051] The above target area is the required research area. The common offset seismic data is obtained by non-uniform spatio-temporal sampling. It can be that the spatial interval of the sampling points is non-uniform, or the time interval of the sampling points is non-uniform, or both the spatial interval and the time interval of the sampling points are non-uniform. The non-uniform spatial interval means that the position intervals between the sampling points of different seismic traces are non-uniform, and the non-uniform time interval means that the time intervals between different sampling points of the same seismic trace are non-uniform.

[0052] The common offset seismic data can include the fluctuation signals sampled by multiple receivers (i.e., geophones) at different times. One receiver corresponds to one seismic trace, and each receiver is arranged on a straight line. The non-uniform spatial interval means that the position intervals of the receivers are non-uniform, and the non-uniform time interval means that the sampling time intervals of the receivers are non-uniform. The common offset seismic data can be denoted as P ( m , t ) m where t represents the position corresponding to the seismic trace or the center point (such as the position of the receiver), m represents the recording time (i.e., the sampling time). Optionally, the position

[0053] Step S120, calculate the plane wave slope for each sampling point of the common offset seismic data by the finite difference method to obtain the plane wave slope data.

[0054] Considering that it is obtained under the uneven spatio-temporal sampling of the common offset seismic data, the spatial difference and the time difference can be calculated separately, and then the plane wave slope can be calculated. Based on this, in some possible embodiments, the above step S120 may include: calculating the spatial difference value and the time difference value for each sampling point according to the fluctuation signals of each sampling point and its adjacent points; wherein, the adjacent points include the sampling points of adjacent seismic traces at the same sampling time and the sampling points of adjacent sampling times on the same seismic trace; calculating the plane wave slope for each sampling point according to the spatial difference value and the time difference value of each sampling point.

[0055] Due to the uneven sampling interval, the intervals between the current sampling point and the front and rear sampling points are usually not equal (the position interval and / or the time interval are not equal), and it is necessary to consider both the forward difference and the backward difference. Based on this, the above spatial difference value can be calculated by the following formula:

[0056] ;

[0057] The above time difference value can be calculated by the following formula:

[0058] ;

[0059] The above plane wave slope a can be calculated by the following formula:

[0060] ;

[0061] wherein, P ( m ) represents the fluctuation signal at position m , P ( m- ) represents the fluctuation signal at position m- , P ( m+ ) represents the fluctuation signal at position m+ , , respectively represent the position intervals between the seismic trace to which the current sampling point belongs and the previous seismic trace and the next seismic trace, P ( t ) represents the fluctuation signal at sampling time t ,P ( t- ) represents the sampling time t- of the fluctuation signal below, P ( t+ ) represents the sampling time t+ of the fluctuation signal below, and respectively represent the time intervals between the sampling time of the current sampling point and the previous sampling time and the next sampling time.

[0062] It should be noted that for the case where only forward difference or backward difference exists, the forward difference value or backward difference value can be directly used as the final difference value. For example, for the first sampling point of the first seismic trace, only backward spatial difference and backward time difference exist. Therefore, the backward spatial difference value of this sampling point is directly determined as its spatial difference value, and the backward time difference value of this sampling point is directly determined as its time difference value; for the last sampling point of the last seismic trace, only forward spatial difference and forward time difference exist. Therefore, the forward spatial difference value of this sampling point is directly determined as its spatial difference value, and the forward time difference value of this sampling point is directly determined as its time difference value.

[0063] Step S130: Determine the travel-time curve of the reflected wave for each sampling point according to the plane-wave slope data.

[0064] The travel-time curve of the reflected wave describes the relationship between the time required for the seismic wave to travel from the source, reflect from the underground formation interface, and return to the surface receiver and the distance between the source and the receiver. In some possible embodiments, the above step S130 may include: calculating the intercept in the travel-time curve of the reflected wave for each sampling point according to the position, sampling time, and plane-wave slope of each sampling point; determining the travel-time curve of the reflected wave for each sampling point according to the plane-wave slope and intercept of each sampling point.

[0065] The reflected wave has a local linear characteristic, and the expression of the travel-time curve of the reflected wave can be as follows:

[0066] .

[0067] Based on this, the above intercept b can be calculated by the following formula:

[0068] ;

[0069] where t represents the sampling time, a represents the plane-wave slope, m represents the position of the seismic trace to which it belongs.

[0070] Step S140: perform diffraction wave separation on common offset seismic data according to the reflection wave travel time curves of each sampling point.

[0071] In some possible embodiments, the above step S140 may include: determining the corresponding reflection wave signal in the common offset seismic data according to the reflection wave travel time curve of each sampling point; and determining the diffraction wave signal of each sampling point as the difference between the fluctuation signal of each sampling point and its reflection wave signal.

[0072] In a possible implementation manner, the reflection wave signal can be separated from the seismic data by using the sliding window averaging method: traverse each sampling point. For the currently traversed sampling point, first determine the relevant seismic data corresponding to the current sampling point according to the preset spatial window length and the reflection wave travel time curve of the current sampling point; then perform an averaging calculation on the relevant seismic data corresponding to the current sampling point to obtain the reflection wave signal of the current sampling point. Specifically, the relevant seismic traces can be determined according to the window length, and the relevant time can be calculated according to the reflection wave travel time curve and the coordinates of the relevant seismic traces. The fluctuation signals at the relevant seismic traces and relevant time are used as the relevant seismic data. The spatial window length can be set according to actual requirements and is not limited here. For example, the spatial window length can be 5. For the sampling point at the 3rd seismic trace and time t 3, its relevant seismic traces are the 1st, 2nd, 3rd, 4th, and 5th seismic traces. Substitute the coordinates of the 1st, 2nd, 3rd, 4th, and 5th seismic traces into the reflection wave travel time curve of this sampling point respectively, and five times t 1, t 2, t 3, t 4, t 5 can be calculated. Thus, the relevant seismic data is the fluctuation signal of the 1st seismic trace at time t 1, the fluctuation signal of the 2nd seismic trace at time t 2, the fluctuation signal of the 3rd seismic trace at time t 3, the fluctuation signal of the 4th seismic trace at time t 4, and the fluctuation signal of the 5th seismic trace at time t 5.

[0073] Optionally, the reflection wave signal can be calculated by the following formula:

[0074] ;

[0075] where represents the reflection wave signal at position m , sampling time t , k represents the number of seismic traces within the given spatial window. Indicating position m + , sampling time The fluctuating signal under Indicating the i th seismic trace within the spatial window and the distance between it and m a 、 b respectively represent the plane wave slope and intercept in the reflection wave travel time curve

[0076] The diffracted wave signal can be expressed as:

[0077] 。

[0078] The diffracted wave separation method under non-uniform spatio-temporal sampling provided by the embodiments of the present invention can obtain the common offset seismic data of the target area. The common offset seismic data includes the fluctuating signals of multiple sampling points, where the position intervals between the sampling points of different seismic traces are non-uniform, and / or the time intervals between different sampling points of the same seismic trace are non-uniform; the plane wave slope of each sampling point is calculated for the common offset seismic data by the finite difference method to obtain the plane wave slope data; the reflection wave travel time curve of each sampling point is determined according to the plane wave slope data; and the diffracted wave separation of the common offset seismic data is performed according to the reflection wave travel time curves of each sampling point. In this way, the diffracted wave separation under non-uniform spatio-temporal sampling is realized by using the finite difference method.

[0079] For the sake of easy understanding, the following will refer to Figure 2 to introduce the above-mentioned diffracted wave separation method under non-uniform spatio-temporal sampling in detail.

[0080] See Figure 2 The flow schematic diagram of another diffracted wave separation method under non-uniform spatio-temporal sampling shown in the figure. This method includes the following four steps:

[0081] The first step: Read the common offset seismic data.

[0082] Read the common offset seismic data P ( m , t ), where m represents the position corresponding to the seismic trace or the center point, t represents the recording time.

[0083] The second step: Calculate the plane wave slope under non-uniform spatio-temporal sampling.

[0084] The plane wave equation can be expressed as:

[0085] (1)。

[0086] Based on this, the slope can be obtained:

[0087] (2).

[0088] Since the sampling space interval is uneven, the intervals between the current position and the front and back positions are usually not equal. Let the interval between the current seismic trace coordinate and the previous seismic trace coordinate be , and the interval difference from the next seismic trace be , then there is a forward difference format:

[0089] (3);

[0090] Backward difference format:

[0091] (4);

[0092] Combining them gives:

[0093] (5).

[0094] Equation (5) is the spatial difference under uneven spatial sampling. Similarly, in terms of time, the difference can be obtained:

[0095] (6);

[0096] In the formula and are the time differences between the current sampling point and the previous and next time sampling points respectively.

[0097] Combining formulas (5) and (6) can obtain the slope in formula (2).

[0098] Step 3: Calculate the reflection wave travel time curve under uneven spatio-temporal sampling.

[0099] The reflection wave has a local linear characteristic. The slope has been obtained in the second step, so the reflection wave travel time curve can be set as:

[0100] (7);

[0101] In the formula b is the intercept. It can be obtained that:

[0102] (8).

[0103] Step 4: Complete the diffraction wave separation.

[0104] The finally obtained reflection wave and diffraction wave can be expressed as:

[0105] (9);

[0106] (10).

[0107] In the formula, k represents the number of seismic traces within a given spatial window, represents the i th seismic trace within the spatial window and the distance between it and m.

[0108] In summary, the embodiment of the present invention proposes a calculation strategy for reflection wave travel time curves based on the finite difference method, which can effectively solve the problem of diffraction wave separation under uneven spatio-temporal sampling. The embodiment of the present invention has the ability to obtain weak signals of seismic diffraction waves and can be used for detecting small-scale geological anomalies in seismic exploration.

[0109] Corresponding to the above diffraction wave separation method under uneven spatio-temporal sampling, the embodiment of the present invention also provides a diffraction wave separation device under uneven spatio-temporal sampling. Refer to Figure 3 the structural schematic diagram of a diffraction wave separation device under uneven spatio-temporal sampling as shown. The device includes:

[0110] An acquisition module 301, configured to acquire common-offset seismic data of a target area. The common-offset seismic data includes fluctuation signals of multiple sampling points, where the position intervals between sampling points of different seismic traces are uneven, and / or the time intervals between different sampling points of the same seismic trace are uneven;

[0111] A calculation module 302, configured to calculate the plane wave slope of each sampling point of the common-offset seismic data by the finite difference method to obtain plane wave slope data;

[0112] A determination module 303, configured to determine the reflection wave travel time curve of each sampling point according to the plane wave slope data;

[0113] A separation module 304, configured to separate the diffraction waves of the common-offset seismic data according to the reflection wave travel time curves of each sampling point.

[0114] The diffraction wave separation device provided by the embodiment of the present invention can acquire the common-offset seismic data of the target area. The common-offset seismic data includes fluctuation signals of multiple sampling points, where the position intervals between sampling points of different seismic traces are uneven, and / or the time intervals between different sampling points of the same seismic trace are uneven; calculate the plane wave slope of each sampling point of the common-offset seismic data by the finite difference method to obtain plane wave slope data; determine the reflection wave travel time curve of each sampling point according to the plane wave slope data; and separate the diffraction waves of the common-offset seismic data according to the reflection wave travel time curves of each sampling point. In this way, the diffraction wave separation under uneven spatio-temporal sampling is realized by using the finite difference method.

[0115] Furthermore, the above calculation module 302 is specifically configured to: calculate the spatial difference value and the time difference value of each sampling point according to the fluctuation signals of each sampling point and its adjacent points; wherein, the adjacent points include the sampling points of adjacent seismic channels at the same sampling time and the sampling points of adjacent sampling times on the same seismic channel; calculate the plane wave slope of each sampling point according to the spatial difference value and the time difference value of each sampling point.

[0116] Furthermore, the spatial difference value is calculated by the following formula:

[0117] ;

[0118] The time difference value is calculated by the following formula:

[0119] ;

[0120] The plane wave slope a is calculated by the following formula:

[0121] ;

[0122] Wherein, P ( m ) represents the fluctuation signal at position m , P ( m- ) represents the fluctuation signal at position m- , P ( m+ ) represents the fluctuation signal at position m+ , , respectively represent the position intervals between the seismic channel to which the current sampling point belongs and the previous seismic channel and the next seismic channel, P ( t ) represents the fluctuation signal at sampling time t , P ( t- ) represents the fluctuation signal at sampling time t- , P ( t+ ) represents the fluctuation signal at sampling time t+ , , respectively represent the time intervals between the sampling time of the current sampling point and the previous sampling time and the next sampling time.

[0123] Further, the determining module 303 is specifically configured to: calculate the intercept in the reflected wave travel time curve of each sampling point according to the position, sampling time, and plane wave slope of each sampling point; determine the reflected wave travel time curve of each sampling point according to the plane wave slope and intercept of each sampling point.

[0124] Further, the intercept b is calculated by the following formula:

[0125] ;

[0126] where t represents the sampling time, a represents the plane wave slope, m represents the position of the seismic trace to which it belongs.

[0127] Further, the separating module 304 is specifically configured to: determine the corresponding reflected wave signal in the common offset seismic data according to the reflected wave travel time curve of each sampling point; determine the diffraction wave signal of each sampling point as the difference between the wave signal of each sampling point and its reflected wave signal.

[0128] Further, the reflected wave signal is calculated by the following formula:

[0129] ;

[0130] where represents the position m , sampling time t under the reflected wave signal, k represents the number of seismic traces within a given spatial window, represents the position m + , sampling time under the wave signal, represents the distance between the i th seismic trace and m within the spatial window, a , b respectively represent the plane wave slope and intercept in the reflected wave travel time curve.

[0131] The diffraction wave separation device under non-uniform spatio-temporal sampling provided in this embodiment has the same implementation principle and the same technical effects as those in the foregoing diffraction wave separation method embodiment under non-uniform spatio-temporal sampling. For the sake of brief description, for the parts not mentioned in the diffraction wave separation device embodiment under non-uniform spatio-temporal sampling, reference may be made to the corresponding content in the foregoing diffraction wave separation method embodiment under non-uniform spatio-temporal sampling.

[0132] As Figure 4 shown, an electronic device 400 provided by an embodiment of the present invention includes: a processor 401, a memory 402, and a bus. The memory 402 stores a computer program that can run on the processor 401. When the electronic device 400 runs, the processor 401 communicates with the memory 402 through the bus, and the processor 401 executes the computer program to implement the diffraction wave separation method under the above-mentioned non-uniform spatio-temporal sampling.

[0133] Specifically, the above-mentioned memory 402 and processor 401 can be general-purpose memory and processor, and no specific limitation is made here.

[0134] An embodiment of the present invention also provides a computer-readable storage medium. A computer program is stored on the computer-readable storage medium, and when the computer program is run by a processor, it executes the diffraction wave separation method under non-uniform spatio-temporal sampling in the foregoing method embodiment. The computer-readable storage medium includes: various media such as a USB flash drive, a mobile hard disk, a read-only memory (ROM), a RAM, a magnetic disk, or an optical disc that can store program codes.

[0135] The term "and / or" in this article is merely a description of the association relationship of associated objects, indicating that three relationships can exist. For example, A and / or B can represent: A exists alone, A and B exist simultaneously, and B exists alone. In addition, the term "at least one" in this article means any one of multiple types or any combination of at least two of multiple types. For example, including at least one of A, B, and C can represent including any one or more elements selected from the set composed of A, B, and C.

[0136] In all the examples shown and described here, any specific value should be construed as merely exemplary and not as a limitation. Therefore, other examples of the exemplary embodiments may have different values.

[0137] The flowcharts and block diagrams in the accompanying drawings illustrate the possible architectures, functions, and operations of apparatuses, methods, and computer program products according to various embodiments of the present invention. In this regard, each block in the flowchart or block diagram may represent a module, a segment of a program, or a part of code, which 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 may actually be executed substantially in parallel, and they may 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 combinations of blocks in the block diagram and / or flowchart, may be implemented by a dedicated hardware-based system that performs the specified functions or actions, or may be implemented by a combination of dedicated hardware and computer instructions.

[0138] In several embodiments provided in the present application, it should be understood that the disclosed apparatuses and methods may be implemented in other ways. The apparatus embodiments described above are merely illustrative. For example, the division of modules is only a logical function division, and there may be other division methods in actual implementation. For another example, multiple modules or components may be combined or integrated into another system, or some features may be ignored or not executed. Another point is that the couplings or direct couplings or communication connections shown or discussed among each other may be through some communication interfaces. The indirect couplings or communication connections of apparatuses or modules may be in electrical, mechanical, or other forms.

[0139] The modules described as separate components may or may not be physically separated, and the components shown as modules may or may not be physical modules, that is, they may be located in one place, or may be distributed to multiple network modules. Some or all of the modules may be selected according to actual needs to achieve the purpose of the solution of this embodiment.

[0140] In addition, the functional modules in various embodiments of the present invention may be integrated into one processing module, or each module may exist physically alone, or two or more modules may be integrated into one module.

[0141] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and are not intended to limit them. Although the present invention has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that they can still modify the technical solutions described in the foregoing embodiments, or perform equivalent replacements for some or all of the technical features; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the scope of the technical solutions of the various embodiments of the present invention.

Claims

1. A diffraction wave separation method under non-uniform spatio-temporal sampling, characterized in that Including: Obtain the common-offset seismic data of the target area, where the common-offset seismic data includes the fluctuation signals of multiple sampling points. Among them, the position intervals between the sampling points of different seismic traces are uneven, and / or the time intervals between different sampling points of the same seismic trace are uneven; Calculate the plane wave slope of each sampling point in the common-offset seismic data by the finite difference method to obtain plane wave slope data; Determine the reflection wave travel-time curve of each sampling point according to the plane wave slope data; Separate the diffracted waves of the common-offset seismic data according to the reflection wave travel-time curves of each sampling point; The step of calculating the plane wave slope of each sampling point in the common-offset seismic data by the finite difference method to obtain plane wave slope data includes: Calculate the spatial difference value and time difference value of each sampling point according to the fluctuation signals of each sampling point and its adjacent points; among them, the adjacent points include the sampling points of adjacent seismic traces at the same sampling time and the sampling points of adjacent sampling times on the same seismic trace; Calculate the plane wave slope of each sampling point according to the spatial difference value and time difference value of each sampling point.

2. The method according to claim 1, characterized in that, The spatial difference value is calculated by the following formula: ； The time difference value is calculated by the following formula: ； The slope of the plane wave a is calculated by the following formula: ； Among them, P ( m ) represents the position m of the fluctuation signal below, P ( m- ) represents the position m- of the fluctuation signal below, P ( m+ ) represents the position m+ of the fluctuation signal below, 、 respectively represent the position intervals between the seismic trace to which the current sampling point belongs and the previous seismic trace and the next seismic trace, P ( t ) represents the sampling time t of the fluctuation signal below, P ( t- ) represents the sampling time t- of the fluctuation signal below, P ( t+ ) represents the sampling time t+ of the fluctuation signal below, 、 respectively represent the time intervals between the sampling time of the current sampling point and the previous sampling time and the next sampling time.

3. The method according to claim 1, wherein The step of determining the reflection wave travel-time curve of each sampling point according to the plane wave slope data includes: Calculate the intercept in the reflection wave travel-time curve of each sampling point according to the position, sampling time and plane wave slope of each sampling point; Determine the reflection wave travel-time curve of each sampling point according to the plane wave slope and intercept of each sampling point.

4. The method according to claim 3, wherein The intercept b is calculated by the following formula: ； Among them, t represents the sampling time, a represents the plane wave slope, m represents the position of the seismic trace to which it belongs.

5. The method according to claim 1, wherein The step of separating the diffracted waves of the common-offset seismic data according to the reflection wave travel-time curves of each sampling point includes: Determine the corresponding reflection wave signal in the common-offset seismic data according to the reflection wave travel-time curve of each sampling point; Determine the diffracted wave signal of each sampling point as the difference between the fluctuation signal of each sampling point and its reflection wave signal.

6. The method according to claim 5, characterized in that The reflection wave signal is calculated by the following formula: ； Among them, represents the position m , the sampling time t under the reflected wave signal, k represents the number of seismic traces within a given spatial window, represents the position m + , the sampling time under the wave signal, represents the distance between the i th seismic trace within the spatial window and m, a , b respectively represent the plane wave slope and intercept in the reflected wave travel time curve.

7. A diffracted wave separation device under non-uniform spatio-temporal sampling, characterized in that Including: An acquisition module for acquiring the common-offset seismic data of the target area, where the common-offset seismic data includes the fluctuation signals of multiple sampling points. Among them, the position intervals between the sampling points of different seismic traces are uneven, and / or the time intervals between different sampling points of the same seismic trace are uneven; A calculation module for calculating the plane wave slope of each sampling point in the common-offset seismic data by the finite difference method to obtain plane wave slope data; A determination module for determining the reflection wave travel-time curve of each sampling point according to the plane wave slope data; A separation module for separating the diffracted waves of the common-offset seismic data according to the reflection wave travel-time curves of each sampling point; The calculation module is specifically configured to: calculate the spatial difference value and the time difference value of each sampling point according to the fluctuation signals of each sampling point and its adjacent points; wherein, the adjacent points include the sampling points of adjacent seismic channels at the same sampling time and the sampling points of adjacent sampling times on the same seismic channel; calculate the plane wave slope of each sampling point according to the spatial difference value and the time difference value of each sampling point.

8. An electronic device, comprising a memory and a processor, wherein a computer program capable of running on the processor is stored in the memory, and is characterized in that When the processor executes the computer program, it implements the diffraction wave separation method under uneven spatio-temporal sampling according to any one of claims 1-6.

9. A computer-readable storage medium, on which a computer program is stored, characterized in that, When the computer program is run by the processor, it executes the diffraction wave separation method under uneven spatio-temporal sampling according to any one of claims 1-6.

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