Diffracted wave separation method and device under non-uniform space-time sampling

Abstract

The invention provides a diffracted wave separation method and device under non-uniform space-time sampling, and relates to the technical field of seismic prospecting, the method comprises the following steps: obtaining common offset seismic data of a target area, the common offset seismic data comprising fluctuation signals of a plurality of sampling points, the position intervals among the sampling points of different seismic traces are non-uniform, and / or the time intervals among 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 through a finite difference method to obtain plane wave slope data; determining a reflected wave travel time curve of each sampling point according to the plane wave slope data; and diffracted wave separation of the common offset seismic data is carried out according to the reflected wave travel time curve of each sampling point. According to the method, accurate diffracted wave separation under non-uniform space-time sampling is realized, and the seismic data analysis accuracy is improved.

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 non-uniform time-space sampling. Background Art

[0002] When seismic waves propagate underground, they will be reflected when encountering the stratum interface to form reflection waves, which can accurately reflect the continuous interface information. Smaller geological discontinuities do not have continuous reflection interfaces and do not produce reflection waves, but instead serve as secondary seismic sources to form diffraction waves. Therefore, seismic diffraction waves are the seismic response of small-scale geological discontinuities, carrying rich small-scale geological body information, and have the potential for high-resolution exploration and important research value.

[0003] However, diffraction waves are affected by geometric diffusion attenuation, and their energy is one to two orders of magnitude lower than that of reflected waves. They will be shielded by the strong signals of reflected waves and cannot realize their high-resolution detection potential. Therefore, it is necessary to separate the diffraction waves, eliminate the shielding effect of reflected waves, and achieve high-resolution detection of diffraction waves. The optimal local dip calculation method based on plane wave decomposition is currently a more effective diffraction wave separation method. However, this method assumes that seismic data is uniformly sampled in time and space, and cannot accurately predict the local dip of reflected waves under uneven time and space sampling, making it difficult to accurately predict reflected waves and separate diffraction waves. Summary of the invention

[0004] The object of the present invention is to provide a diffraction wave separation method and device under non-uniform time and space sampling, so as to realize the diffraction wave separation under non-uniform time and space sampling.

[0005] In a first aspect, the present invention provides a diffraction wave separation method under non-uniform spatiotemporal sampling, comprising: Acquire common-offset seismic data of a target area, the common-offset seismic data comprising fluctuation signals of a plurality of sampling points, wherein 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; The plane wave slope data is obtained by calculating the plane wave slope of each sampling point of the common offset seismic data by using the finite difference method; According to the plane wave slope data, the travel time curve of the reflected wave at each sampling point is determined; The diffraction wave separation of common offset seismic data is performed based on the reflection wave travel time curves of each sampling point.

[0006] In an optional embodiment, the step of calculating the plane wave slope of each sampling point of the common offset seismic data by a finite difference method to obtain the plane wave slope data comprises: According to the fluctuation signals of each sampling point and its adjacent points, the spatial difference value and the time difference value of each sampling point are calculated; 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 under the same seismic channel; The plane wave slope of each sampling point is calculated based on the spatial difference value and the temporal difference value of each sampling point.

[0007] In an optional embodiment, the spatial difference value Calculated by the following formula: ; Time difference value Calculated by the following formula: ; Plane wave slope a Calculated by the following formula: ; in, P ( m ) indicates the position m The fluctuation signal below P ( m- ) indicates the position m- The fluctuation signal below P ( m+ ) indicates the position m+ The fluctuation signal below , They represent the position interval between the seismic trace to which the current sampling point belongs and the previous seismic trace and the next seismic trace respectively. P ( t ) represents the sampling time t The fluctuation signal below P ( t- ) represents the sampling time t- The fluctuation signal below P ( t+ ) represents the sampling time t+ The fluctuation signal below , They respectively represent the time interval between the sampling time of the current sampling point and the previous sampling time and the next sampling time.

[0008] In an optional embodiment, the step of determining the reflected wave travel time curve of each sampling point according to the plane wave slope data includes: According to the position, sampling time and plane wave slope of each sampling point, the intercept of the reflected wave travel time curve of each sampling point is calculated; According to the plane wave slope and intercept of each sampling point, the reflected wave travel time curve of each sampling point is determined.

[0009] In an alternative embodiment, the intercept b Calculated by the following formula: ; in, t represents the sampling time, a represents the plane wave slope, m Indicates the location of the seismic channel to which it belongs.

[0010] In an optional embodiment, the step of performing diffraction wave separation of common offset seismic data according to the reflection wave travel time curve of each sampling point includes: According to the reflection wave travel time curve of each sampling point, the corresponding reflection wave signal in the common offset seismic data is determined; The difference between the fluctuation signal of each sampling point and its reflected wave signal is determined as the diffraction wave signal of each sampling point.

[0011] In an optional implementation manner, the reflected wave signal is calculated using the following formula: ; in, Indicates location m , Sampling time t The reflected wave signal under k represents the number of seismic traces in a given spatial window, Indicates location m + , Sampling time The fluctuation signal below Indicates the first i The distance between the seismic trace and m, a , b They represent the plane wave slope and intercept in the reflected wave travel time curve, respectively.

[0012] In a second aspect, the present invention provides a diffraction wave separation device under non-uniform spatiotemporal sampling, comprising: An acquisition module, used for acquiring common offset seismic data of a target area, wherein the common offset seismic data includes fluctuation signals of a plurality of sampling points, wherein 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; A calculation module, used for calculating the plane wave slope of each sampling point on the common offset seismic data by a finite difference method to obtain plane wave slope data; A determination module, used for determining a travel time curve of a reflected wave at each sampling point according to the plane wave slope data; The separation module is used to separate the diffraction waves of the common offset seismic data according to the reflection wave travel time curve of each sampling point.

[0013] In a third aspect, the present invention provides an electronic device comprising a memory and a processor, wherein the memory stores a computer program that can be run on the processor, and when the processor executes the computer program, the diffraction wave separation method under non-uniform spatiotemporal sampling of any one of the aforementioned embodiments is implemented.

[0014] In a fourth aspect, the present invention provides a computer-readable storage medium having a computer program stored thereon. When the computer program is executed by a processor, the diffraction wave separation method under non-uniform spatiotemporal sampling of any one of the aforementioned embodiments is executed.

[0015] The diffraction wave separation method and device under uneven time and space sampling provided by the present invention can obtain the common offset seismic data of the target area, the common offset seismic data includes the fluctuation signals of multiple sampling points, wherein the position intervals between the sampling points of different seismic channels are uneven, and / or the time intervals between different sampling points of the same seismic channel are uneven; the plane wave slope of each sampling point of the common offset seismic data is calculated by the finite difference method to obtain the plane wave slope data; according to the plane wave slope data, the reflection wave travel time curve of each sampling point is determined; according to the reflection wave travel time curve of each sampling point, the diffraction wave separation of the common offset seismic data is performed. In this way, the diffraction wave separation under uneven time and space sampling is realized by using the finite difference method. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] In order to more clearly illustrate the specific implementation methods of the present invention or the technical solutions in the prior art, the drawings required for use in the specific implementation methods or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are some implementation methods of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0017] Figure 1 A schematic flow chart of a diffraction wave separation method under non-uniform spatiotemporal sampling provided by an embodiment of the present invention; Figure 2 A schematic flow chart of another diffraction wave separation method under non-uniform spatiotemporal sampling provided by an embodiment of the present invention; Figure 3A schematic diagram of the structure of a diffraction wave separation device under non-uniform spatiotemporal sampling provided by an embodiment of the present invention; Figure 4 A schematic diagram of the structure of an electronic device provided by an embodiment of the present invention. DETAILED DESCRIPTION

[0018] The technical solution of the present invention will be clearly and completely described below in conjunction with the embodiments. Obviously, the described embodiments are part of the embodiments of the present invention, rather than all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0019] The optimal local dip calculation method based on plane wave decomposition is currently a relatively effective diffraction wave separation method. However, this method assumes that seismic data is uniformly sampled in time and space. It is difficult to accurately predict the reflected wave under uneven time and space 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, uneven sampling interval information can be introduced to estimate the local dip to achieve the calculation of the reflection wave travel time curve and complete the diffraction wave separation target. Based on this, a diffraction wave separation method and device under uneven time and space sampling provided by an embodiment of the present invention proposes a reflection wave travel time curve calculation strategy based on the finite difference method for uneven time and space sampling conditions, which can be used for diffraction wave separation under uneven time and space sampling, effectively solve the diffraction wave separation problem under uneven time and space sampling, and accurately locate geological discontinuities, such as faults, collapse columns, etc. The embodiment of the present invention has the ability to obtain weak signals of seismic diffraction waves, and can serve the detection of small-scale geological anomalies in seismic exploration.

[0020] To facilitate understanding of this embodiment, a diffraction wave separation method under non-uniform spatiotemporal sampling disclosed in an embodiment of the present invention is first introduced in detail.

[0021] The embodiment of the present invention provides a diffraction wave separation method under uneven time and space sampling, which can be executed by an electronic device with data processing capability. The embodiment of the present invention proposes an effective diffraction wave separation method under uneven time and space sampling, which uses a finite difference method to calculate the slope of the event axis of the reflected wave, and then obtains the intercept and the travel time curve of the reflected wave. The travel time curve can be used to calculate the travel time of the reflected wave at any position, and finally realizes the separation of the reflected wave and the diffraction wave.

[0022] See also Figure 1 The flowchart of a diffraction wave separation method under non-uniform spatiotemporal sampling is shown in FIG. 1 , and the method mainly includes the following steps S110 to S140: Step S110, acquiring common-offset seismic data of the target area, the common-offset seismic data comprising fluctuation signals of multiple sampling points, wherein 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.

[0023] The above target area is the required research area. The common offset seismic data is obtained by uneven temporal and spatial sampling. The spatial interval of the sampling points may be uneven, the time interval of the sampling points may be uneven, or both the spatial interval and the time interval of the sampling points may be uneven. The uneven spatial interval means that the position interval between the sampling points of different seismic channels is uneven, and the uneven time interval means that the time interval between different sampling points of the same seismic channel is uneven.

[0024] Common offset seismic data can include wave signals sampled by multiple receivers (i.e., geophones) at different times. One receiver corresponds to one seismic trace, and each receiver is set on a straight line. Uneven spatial spacing refers to uneven position spacing of the receivers, and uneven time intervals refer to uneven sampling time intervals of the receivers. Common offset seismic data can be recorded as P ( m , t ),in, m Indicates the location corresponding to the seismic channel or center point (such as the location of the receiver), t represents the recording time (i.e. sampling time). Optionally, the position m The absolute coordinates or relative coordinates in the receiver arrangement direction (i.e. the straight line where the receivers are located) can be used, or the distance between the receivers and the source can be used.

[0025] Step S120, calculating the plane wave slope of each sampling point on the common offset seismic data by using a finite difference method to obtain plane wave slope data.

[0026] Considering the uneven spatiotemporal sampling of the common offset seismic data, the spatial difference and time difference can be calculated respectively, and then the plane wave slope can be calculated. Based on this, in some possible embodiments, the above step S120 may include: according to the fluctuation signal of each sampling point and its adjacent points, the spatial difference value and the time difference value of each sampling point are calculated; 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 under the same seismic channel; according to the spatial difference value and the time difference value of each sampling point, the plane wave slope of each sampling point is calculated.

[0027] Since the sampling interval is not uniform, the intervals between the current sampling point and the previous and next sampling points are usually not equal (the position interval and / or time interval are not equal), and both forward and backward differences need to be considered. Based on this, the above spatial difference value It can be calculated by the following formula: ; The above time difference value It can be calculated by the following formula: ; The above plane wave slope a It can be calculated by the following formula: ; in, P ( m ) indicates the position m The fluctuation signal below P ( m- ) indicates the position m- The fluctuation signal below P ( m+ ) indicates the position m+ The fluctuation signal below , They represent the position interval between the seismic trace to which the current sampling point belongs and the previous seismic trace and the next seismic trace respectively. P ( t ) represents the sampling time t The fluctuation signal below P ( t- ) represents the sampling time t- The fluctuation signal below P ( t+ ) represents the sampling time t+ The fluctuation signal below , They respectively represent the time interval between the sampling time of the current sampling point and the previous sampling time and the next sampling time.

[0028] It should be noted that, in the case where there is only a forward difference or a backward difference, the forward difference value or the backward difference value can be directly used as the final difference value. For example, for the first sampling point of the first seismic channel, there is only a backward spatial difference and a backward time difference, therefore, the backward spatial difference value of the sampling point is directly determined as its spatial difference value, and the backward time difference value of the sampling point is determined as its time difference value; for the last sampling point of the last seismic channel, there is only a forward spatial difference and a forward time difference, therefore, the forward spatial difference value of the sampling point is directly determined as its spatial difference value, and the forward time difference value of the sampling point is determined as its time difference value.

[0029] Step S130, determining the reflected wave travel time curve of each sampling point according to the plane wave slope data.

[0030] The reflection wave travel time curve describes the relationship between the time required for a seismic wave to start from the earthquake source, reflect from the underground stratum interface and return to the ground receiver and the distance between the earthquake source and the receiver. In some possible embodiments, the above step S130 may include: calculating 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; determining the reflection wave travel time curve of each sampling point according to the plane wave slope and intercept of each sampling point.

[0031] The reflected wave has local linear characteristics, and the expression of the reflected wave travel time curve can be as follows: .

[0032] Based on this, the above intercept b It can be calculated by the following formula: ; in, t represents the sampling time, a represents the plane wave slope, m Indicates the location of the seismic channel to which it belongs.

[0033] Step S140 , performing diffraction wave separation of common-offset seismic data according to the reflection wave travel time curves of each sampling point.

[0034] 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 difference between the fluctuation signal of each sampling point and its reflection wave signal as the diffraction wave signal of each sampling point.

[0035] In one possible implementation, the sliding window averaging method can be used to separate the reflected wave signal from the seismic data: traverse each sampling point, and for the current sampling point traversed, first determine the relevant seismic data corresponding to the current sampling point based on the preset spatial window length and the reflection wave travel time curve of the current sampling point; then average the relevant seismic data corresponding to the current sampling point to obtain the reflected wave signal of the current sampling point. Specifically, the relevant seismic trace 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 trace, and the fluctuation signal under the relevant seismic trace and the relevant time is used as the relevant seismic data. The spatial window length can be set according to actual needs and is not limited here. For example, the spatial window length can be 5. For the third seismic trace, time t 3 The sampling point under the above condition has the 1st, 2nd, 3rd, 4th and 5th seismic traces. By inserting the coordinates of the 1st, 2nd, 3rd, 4th and 5th seismic traces into the reflection wave travel time curve of the sampling point, five time points can be calculated. t 1 , t 2 , t 3 , t 4 , t 5 , so the relevant seismic data is the first seismic trace at time t 1 The fluctuation signal under the second seismic trace is t 2 The fluctuation signal under the third seismic trace is t 3 The fluctuation signal under the fourth seismic trace is t 4 The wave signal and the fifth seismic trace at time t 5 The following fluctuation signal.

[0036] Optionally, the reflected wave signal can be calculated using the following formula: ; in, Indicates location m , Sampling time t The reflected wave signal under k represents the number of seismic traces in a given spatial window, Indicates location m + , Sampling time The fluctuation signal below Indicates the first iThe distance between the seismic trace and m, a , b They represent the plane wave slope and intercept in the reflected wave travel time curve, respectively.

[0037] The diffraction wave signal can be expressed as: .

[0038] The diffraction wave separation method under uneven time and space sampling provided by the embodiment of the present invention can obtain the common offset seismic data of the target area, and the common offset seismic data includes the fluctuation signals of multiple sampling points, wherein the position intervals between the sampling points of different seismic channels are uneven, and / or the time intervals between different sampling points of the same seismic channel are uneven; the plane wave slope of each sampling point of the common offset seismic data is calculated by the finite difference method to obtain the plane wave slope data; according to the plane wave slope data, the reflection wave travel time curve of each sampling point is determined; according to the reflection wave travel time curve of each sampling point, the diffraction wave separation of the common offset seismic data is performed. In this way, the diffraction wave separation under uneven time and space sampling is realized by using the finite difference method.

[0039] For ease of understanding, refer to Figure 2 The diffraction wave separation method under the above-mentioned inhomogeneous spatiotemporal sampling is introduced in detail.

[0040] See also Figure 2 FIG. 1 is a flow chart of another diffraction wave separation method under non-uniform spatiotemporal sampling, the method comprising the following four steps: Step 1: Read common offset seismic data.

[0041] Read common offset seismic data P ( m , t ),in, m Indicates the location corresponding to the seismic trace or center point, t Indicates the recording time.

[0042] Step 2: Calculate the plane wave slope under non-uniform spatiotemporal sampling.

[0043] The plane wave equation can be expressed as: (1).

[0044] Based on this, the slope is: (2).

[0045] Since the sampling space is not uniform, the intervals between the current position and the previous and next positions are usually not equal. Suppose the interval between the current seismic trace coordinates and the previous seismic trace coordinates is , and the interval between the next seismic trace is , then there is a forward difference format: (3); Backward difference format: (4); In summary: (5).

[0046] Formula (5) is the spatial difference under uneven spatial sampling. Similarly, in time, the difference can be obtained: (6); In the formula and They are the time difference between the current sampling point and the previous sampling point and the next sampling point respectively.

[0047] Combining formulas (5) and (6), the slope in formula (2) can be obtained.

[0048] Step 3: Calculate the travel time curve of the reflected wave under non-uniform space-time sampling.

[0049] The reflected wave has local linear characteristics. The slope has been obtained in the second step, so the reflected wave travel time curve can be set as: (7); In the formula b is the intercept. We can get: (8).

[0050] Step 4: Complete diffraction wave separation.

[0051] The final reflected wave and diffracted wave can be expressed as: (9); (10).

[0052] In the formula, k represents the number of seismic traces in a given spatial window, Indicates the first i The distance between the seismic traces is m.

[0053] In summary, the embodiment of the present invention proposes a reflection wave travel time curve calculation strategy based on the finite difference method, which can effectively solve the diffraction wave separation problem under uneven time and space sampling. The embodiment of the present invention has the ability to obtain weak signals of seismic diffraction waves and can serve the detection of small-scale geological anomalies in seismic exploration.

[0054] Corresponding to the above-mentioned diffraction wave separation method under non-uniform spatiotemporal sampling, an embodiment of the present invention further provides a diffraction wave separation device under non-uniform spatiotemporal sampling. Figure 3 A structural schematic diagram of a diffraction wave separation device under non-uniform spatiotemporal sampling is shown, the device comprising: An acquisition module 301 is used to acquire common offset seismic data of a target area, wherein the common offset seismic data includes fluctuation signals of multiple sampling points, wherein 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; A calculation module 302 is used to calculate the plane wave slope of each sampling point on the common offset seismic data by a finite difference method to obtain plane wave slope data; A determination module 303, for determining a travel time curve of a reflected wave at each sampling point according to the plane wave slope data; The separation module 304 is used to perform diffraction wave separation of the common offset seismic data according to the reflection wave travel time curve of each sampling point.

[0055] The diffraction wave separation device under uneven time and space sampling provided by the embodiment of the present invention can obtain the common offset seismic data of the target area, and the common offset seismic data includes the fluctuation signals of multiple sampling points, wherein the position intervals between the sampling points of different seismic channels are uneven, and / or the time intervals between different sampling points of the same seismic channel are uneven; the plane wave slope of each sampling point of the common offset seismic data is calculated by the finite difference method to obtain the plane wave slope data; according to the plane wave slope data, the reflection wave travel time curve of each sampling point is determined; according to the reflection wave travel time curve of each sampling point, the diffraction wave separation of the common offset seismic data is performed. In this way, the diffraction wave separation under uneven time and space sampling is realized by using the finite difference method.

[0056] Furthermore, the above-mentioned calculation module 302 is specifically used to: calculate the spatial differential value and the time differential 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 under the same seismic channel; calculate the plane wave slope of each sampling point according to the spatial differential value and the time differential value of each sampling point.

[0057] Furthermore, the spatial difference value Calculated by the following formula: ; Time difference value Calculated by the following formula: ; Plane wave slopea Calculated by the following formula: ; in, P ( m ) indicates the position m The fluctuation signal below P ( m- ) indicates the position m- The fluctuation signal below P ( m+ ) indicates the position m+ The fluctuation signal below , They represent the position interval between the seismic trace to which the current sampling point belongs and the previous seismic trace and the next seismic trace respectively. P ( t ) represents the sampling time t The fluctuation signal below P ( t- ) represents the sampling time t- The fluctuation signal below P ( t+ ) represents the sampling time t+ The fluctuation signal below , They respectively represent the time interval between the sampling time of the current sampling point and the previous sampling time and the next sampling time.

[0058] Furthermore, the determination module 303 is specifically used to: calculate the intercept of the reflected wave travel time curve of each sampling point according to the position, sampling time and plane wave slope of each sampling point; and determine the reflected wave travel time curve of each sampling point according to the plane wave slope and intercept of each sampling point.

[0059] Furthermore, the intercept b Calculated by the following formula: ; in, t represents the sampling time, a represents the plane wave slope, m Indicates the location of the seismic channel to which it belongs.

[0060] Furthermore, the separation module 304 is specifically used to: determine the corresponding reflection wave signal in the common offset seismic data according to the reflection wave travel time curve of each sampling point; and determine the difference between the fluctuation signal and the reflection wave signal of each sampling point as the diffraction wave signal of each sampling point.

[0061] Furthermore, the reflected wave signal is calculated by the following formula: ; in, Indicates location m , Sampling time t The reflected wave signal under k represents the number of seismic traces in a given spatial window, Indicates location m + , Sampling time The fluctuation signal below Indicates the first i The distance between the seismic trace and m, a , b They represent the plane wave slope and intercept in the reflected wave travel time curve, respectively.

[0062] The diffraction wave separation device under non-uniform space-time sampling provided in this embodiment has the same implementation principle and technical effects as those of the aforementioned diffraction wave separation method embodiment under non-uniform space-time sampling. For the sake of brief description, for matters not mentioned in the embodiment of the diffraction wave separation device under non-uniform space-time sampling, reference may be made to the corresponding contents in the aforementioned diffraction wave separation method embodiment under non-uniform space-time sampling.

[0063] like Figure 4 As shown, an electronic device 400 provided in 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 be run on the processor 401, when the electronic device 400 is running, the processor 401 and the memory 402 communicate through the bus, and the processor 401 executes the computer program to implement the above-mentioned diffraction wave separation method under non-uniform spatiotemporal sampling.

[0064] Specifically, the memory 402 and the processor 401 can be general-purpose memories and processors, which are not specifically limited here.

[0065] The embodiment of the present invention further provides a computer-readable storage medium, on which a computer program is stored, and when the computer program is executed by a processor, the diffraction wave separation method under non-uniform spatiotemporal sampling in the previous method embodiment is executed. The computer-readable storage medium includes: a U disk, a mobile hard disk, a read-only memory (ROM), a RAM, a magnetic disk or an optical disk, and other media that can store program codes.

[0066] The term "and / or" herein is only a description of the association relationship of the associated objects, indicating that there may be three relationships. For example, A and / or B can represent: A exists alone, A and B exist at the same time, and B exists alone. In addition, the term "at least one" herein represents any combination of at least two of any one or more of a plurality of. For example, including at least one of A, B, and C can represent including any one or more elements selected from the set consisting of A, B, and C.

[0067] In all examples shown and described herein, any specific values ​​should be interpreted as merely exemplary and not as limiting, and thus other examples of the exemplary embodiments may have different values.

[0068] The flowcharts and block diagrams in the accompanying drawings show the possible architecture, functions and operations of the devices, methods and computer program products according to multiple embodiments of the present invention. In this regard, each box in the flowchart or block diagram can represent a module, a program segment or a part of a code, and a part of a module, a program segment or a code contains one or more executable instructions for realizing the specified logical function. It should also be noted that in some alternative implementations, the functions marked in the box can also occur in a different order from the order marked in the accompanying drawings. For example, two consecutive boxes can actually be executed substantially in parallel, and they can sometimes be executed in the opposite order, depending on the functions involved. It should also be noted that each box in the block diagram and / or the flowchart, and the combination of the boxes in the block diagram and / or the flowchart can be implemented with a dedicated hardware-based system that performs a specified function or action, or can be implemented with a combination of dedicated hardware and computer instructions.

[0069] In the several embodiments provided in the present application, it should be understood that the disclosed devices and methods can be implemented in other ways. The device embodiments described above are only schematic. For example, the division of modules is only a logical function division. There may be other division methods in actual implementation. For example, multiple modules or components can be combined or integrated into another system, or some features can be ignored or not executed. Another point is that the mutual coupling or direct coupling or communication connection shown or discussed can be through some communication interfaces, and the indirect coupling or communication connection of devices or modules can be electrical, mechanical or other forms.

[0070] 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 distributed on 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.

[0071] In addition, each functional module in each embodiment of the present invention may be integrated into one processing module, or each module may exist physically separately, or two or more modules may be integrated into one module.

[0072] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or replace some or all of the technical features therein with equivalents. However, these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A diffraction wave separation method under non-uniform spatiotemporal sampling, characterized in that: include: Acquire common-offset seismic data of a target area, wherein the common-offset seismic data includes 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; Calculating the plane wave slope of each sampling point on the common offset seismic data by a finite difference method to obtain plane wave slope data; Determine the travel time curve of the reflected wave at each sampling point according to the plane wave slope data; The diffraction wave separation of the common offset seismic data is performed according to the reflection wave travel time curves of each sampling point.

2. The method according to claim 1, characterized in that The step of calculating the plane wave slope of each sampling point on the common offset seismic data by a finite difference method to obtain plane wave slope data comprises: According to the fluctuation signals of each sampling point and its adjacent points, the spatial difference value and the temporal difference value of each sampling point are calculated; wherein the adjacent points include sampling points of adjacent seismic channels at the same sampling time and sampling points of adjacent sampling times under the same seismic channel; The plane wave slope of each sampling point is calculated according to the spatial difference value and the temporal difference value of each sampling point.

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

4. The method according to claim 1, characterized in that: The step of determining the travel time curve of the reflected wave at each sampling point according to the plane wave slope data comprises: According to the position, sampling time and plane wave slope of each sampling point, the intercept of the reflected wave travel time curve of each sampling point is calculated; According to the plane wave slope and intercept of each sampling point, the reflected wave travel time curve of each sampling point is determined.

5. The method according to claim 4, characterized in that The intercept b Calculated by the following formula: ； in, t represents the sampling time, a represents the plane wave slope, m Indicates the location of the seismic channel to which it belongs.

6. The method according to claim 1, characterized in that The step of performing diffraction wave separation of the common offset seismic data according to the reflection wave travel time curves of each sampling point comprises: Determining the corresponding reflection wave signal in the common offset seismic data according to the reflection wave travel time curve of each sampling point; The difference between the fluctuation signal of each sampling point and its reflected wave signal is determined as the diffraction wave signal of each sampling point.

7. The method according to claim 6, characterized in that The reflected wave signal is calculated by the following formula: ； in, Indicates location m , Sampling time t The reflected wave signal under k represents the number of seismic traces in a given spatial window, Indicates location m + , Sampling time The fluctuation signal below Indicates the first i The distance between the seismic trace and m, a , b They represent the plane wave slope and intercept in the reflected wave travel time curve, respectively.

8. A diffraction wave separation device under non-uniform spatiotemporal sampling, characterized in that: include: An acquisition module, used for acquiring common-offset seismic data of a target area, wherein the common-offset seismic data includes 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; A calculation module, used for calculating the plane wave slope of each sampling point on the common offset seismic data by a finite difference method to obtain plane wave slope data; A determination module, used to determine the travel time curve of the reflected wave at each sampling point according to the plane wave slope data; The separation module is used to separate the diffraction waves of the common offset seismic data according to the reflection wave travel time curves of each sampling point.

9. An electronic device comprising a memory and a processor, wherein the memory stores a computer program that can be run on the processor, characterized in that: When the processor executes the computer program, the diffraction wave separation method under non-uniform spatiotemporal sampling according to any one of claims 1 to 7 is implemented.

10. A computer-readable storage medium having a computer program stored thereon, characterized in that: When the computer program is executed by a processor, the diffraction wave separation method under inhomogeneous spatiotemporal sampling according to any one of claims 1 to 7 is executed.

Images