A refracted wave velocity picking method, system, device and storage medium

Abstract

The present invention relates to a method, system, device and storage medium for picking up refracted wave velocity, which obtains a single-shot record of seismic exploration, sets the time and velocity scanning intervals and scanning intervals based on the recording track time at the shot point. A time-channel two-dimensional window is introduced to perform a time and velocity nested loop; a time-channel two-dimensional window correlation analysis technology is proposed to perform a time-channel two-dimensional window correlation analysis on each group of scanning time and scanning speed to obtain the corresponding optimized superposition amplitude. Then, the velocity spectrum is calculated and plotted, and the maximum value of the velocity spectrum is read in combination with the single-shot record of the seismic wave. The scanning speed corresponding to the maximum value is the refracted wave velocity of the corresponding refracted wave. The method uses the optimized superposition amplitude calculated by the window correlation analysis technology to determine the refracted wave velocity, and has the characteristics of high analysis accuracy and strong anti-interference ability. Not only can the initial refracted wave velocity be picked up, but also the subsequent refracted wave velocity can be extracted, which strongly supports the application of the refracted wave method in seismic exploration.

Description

Technical Field

[0001] The present invention relates to the field of geophysical exploration technology, and in particular to a refracted wave velocity picking method, system, device and storage medium. Background Art

[0002] Refraction is a method used in seismic exploration. Seismic exploration involves artificially generating seismic waves (elastic waves). As seismic waves propagate through a medium, their path, amplitude, frequency, and other characteristics vary depending on the elastic properties and geometry of the medium. Seismic exploration involves using geophones placed along a survey line to detect the ground vibrations caused by seismic waves. By studying the amplitude, frequency, and phase characteristics of these waves, the lithology and structure of the subsurface medium can be inferred. Seismic exploration records often produce various types of seismic waves, including direct waves, refracted waves, reflected waves, and surface waves. Refraction is a method of studying the subsurface medium using refracted waves from seismic exploration. After being generated by an earthquake source, seismic waves propagate through the strata, producing refraction when they encounter different media. By measuring the timing and path of refracted waves, information such as the depth, thickness, and structural properties of the strata can be inferred.

[0003] Existing methods for picking refracted wave velocities in seismic exploration are significantly affected by the quality of the first-arrival signal. A high first-arrival signal-to-noise ratio (SNR) leads to high initial value picking accuracy, resulting in high refracted wave velocity picking accuracy. Conversely, high initial value noise in seismic records leads to low refracted wave velocity picking accuracy. However, a single-shot seismic exploration recording contains various types of seismic waves, which intersect and overlap, interfering with the refracted waves and affecting the accuracy of refracted wave velocity extraction. Summary of the Invention

[0004] In order to solve the above technical problems, the present invention provides a refracted wave velocity picking method, system, equipment and storage medium, which introduces a two-dimensional window of time-channel number and correlation analysis technology into the linear scanning technology, and can accurately and effectively extract the first-arrival refracted wave velocity and the subsequent-arrival refracted wave velocity, with strong anti-interference ability and high analysis accuracy.

[0005] In a first aspect, the present application provides a method for picking up refracted wave velocity, comprising:

[0006] Obtain single shot records for seismic surveys;

[0007] According to the single shot record, a time scan interval, a time scan interval, a speed scan interval and a speed scan interval are set;

[0008] Introducing a time-channel two-dimensional window, and setting the time width, number of channels, and window movement interval of the time-channel two-dimensional window according to a preset scanning time and a preset scanning speed;

[0009] Using a two-dimensional window correlation analysis technique, the time-channel two-dimensional window is slid according to the window movement interval to obtain a plurality of time-channel two-dimensional scanning windows. Window correlation analysis is performed on each of the time-channel two-dimensional scanning windows to calculate the optimized superposition amplitude of the time-channel two-dimensional scanning windows corresponding to the scanning time and the scanning speed.

[0010] Perform time and speed nested loops according to the time scanning interval and scanning interval, and the speed scanning interval and scanning interval, and calculate the optimized superposition amplitude corresponding to each set of scanning time and speed using a two-dimensional window correlation analysis technique;

[0011] Based on the optimized superposition amplitude, a refracted wave velocity spectrum is drawn, and a scanning speed corresponding to a maximum value of the refracted wave velocity spectrum is obtained as a target refracted wave velocity.

[0012] In a second aspect, the present application provides a refracted wave velocity picking system, comprising:

[0013] An acquisition module is used to obtain single shot records of seismic exploration;

[0014] A scanning setting module, used to set the time scanning interval, time scanning interval, speed scanning interval and speed scanning interval according to the single shot recording diagram;

[0015] A two-dimensional window module is used to introduce a time-channel two-dimensional window and set the time width, number of channels and window movement interval of the time-channel two-dimensional window according to a preset scanning time and a preset scanning speed;

[0016] a two-dimensional window correlation analysis module, configured to employ a two-dimensional window correlation analysis technique to slide the time-channel two-dimensional window according to the window movement interval to obtain a plurality of time-channel two-dimensional scanning windows, perform window correlation analysis on each of the time-channel two-dimensional scanning windows, and calculate an optimized superposition amplitude of the time-channel two-dimensional scanning windows corresponding to the scanning time and the scanning speed;

[0017] A speed-time nested loop module is used to perform a time and speed nested loop according to the time scanning interval and scanning interval, and the speed scanning interval and scanning interval, and calculate the optimized superposition amplitude corresponding to each set of scanning time and speed using a two-dimensional window correlation analysis technology;

[0018] The velocity spectrum analysis module is used to draw a refracted wave velocity spectrum based on the optimized superposition amplitude, and obtain a scanning speed corresponding to a maximum value of the refracted wave velocity spectrum as a target refracted wave velocity.

[0019] In a third aspect, the present application provides a computer device comprising a processor, a memory, and a computer program stored in the memory and executable on the processor, wherein the processor implements the steps of any of the above methods when executing the computer program.

[0020] In a fourth aspect, the present application provides a computer-readable storage medium, wherein the computer-readable storage medium stores a computer program, and when the computer program is executed by a processor, the steps of any one of the methods described above are implemented.

[0021] This application provides a method for picking refracted wave velocities, improving upon the existing linear scanning (τ-p transform) approach. By introducing a two-dimensional window based on time and channel number, sliding the window, and using window correlation analysis techniques, this method optimizes the stacked amplitude and effectively filters out interfering waveforms with low similarity, thereby accurately extracting refracted wave velocities. This method exhibits strong interference resistance and high picking accuracy, enabling the extraction of both first-arrival and subsequent-arrival refracted wave velocities, significantly supporting the application of refracted wave seismic exploration. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without any creative work.

[0023] Figure 1 A flow chart of a refracted wave velocity picking method provided in an embodiment of the present application;

[0024] Figure 2 A typical seismic exploration single shot record provided in the embodiment of this application;

[0025] Figure 3 A two-dimensional window setting diagram provided in an embodiment of the present application;

[0026] Figure 4 A two-dimensional window correlation analysis flow chart provided in an embodiment of the present application;

[0027] Figure 5 A flow chart of a time-speed scanning two-dimensional window correlation analysis provided in an embodiment of the present application;

[0028] Figure 6 An optimized superposition amplitude is provided in an embodiment of the present application to draw an optimized correlation velocity spectrum;

[0029] Figure 7A window correlation analysis refracted wave velocity pick-up diagram provided in an embodiment of the present application;

[0030] Figure 8 A structural diagram of a refracted wave velocity pickup system provided in an embodiment of the present application;

[0031] Figure 9 A schematic diagram of the structure of a computer device provided in an embodiment of the present application. DETAILED DESCRIPTION

[0032] The following is a clear and complete description of the technical solutions in the embodiments of the present invention in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments in the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present invention. The flowchart used in this application shows the operations implemented in some embodiments of the embodiments of the present application. It should be understood that the operations of the flowchart can be implemented out of sequence, and steps without logical context can be reversed or implemented simultaneously. In addition, under the guidance of the content of this application, those skilled in the art can add at least one other operation to the flowchart, or remove at least one operation from the flowchart.

[0033] In addition, the descriptions of "first", "second", etc. in the present invention are for descriptive purposes only and should not be understood as indicating or implying their relative importance or implicitly indicating the number of the technical features indicated. Therefore, the features defined as "first" or "second" may explicitly or implicitly include at least one of such features. In addition, the technical solutions between the various embodiments can be combined with each other, but this must be based on the fact that they can be implemented by ordinary technicians in this field. When the combination of technical solutions is contradictory or cannot be implemented, it should be deemed that such combination of technical solutions does not exist and is not within the scope of protection required by the present invention.

[0034] First, see Figure 1 and Figure 2 , Figure 1 This is a flowchart of a method for picking up refracted wave velocity provided in an embodiment of the present application. Figure 2 A typical seismic exploration single shot record provided in the embodiment of the present application. A refracted wave velocity picking method provided in the embodiment of the present application includes:

[0035] S101, obtain single shot records of seismic exploration;

[0036] S102, setting a time scan interval, a time scan interval, a speed scan interval, and a speed scan interval according to the single shot record;

[0037] S103, introducing a time-channel two-dimensional window, and setting the time width, number of channels, and window movement interval of the time-channel two-dimensional window according to a preset scanning speed and a preset scanning time;

[0038] S104, using a two-dimensional window correlation analysis technique, sliding the time-channel two-dimensional window according to the window movement interval to obtain a plurality of time-channel two-dimensional scanning windows, performing window correlation analysis on each of the time-channel two-dimensional scanning windows, and calculating an optimized superposition amplitude corresponding to the scanning time and the scanning speed;

[0039] S105, performing a time and speed nested loop according to the time scanning interval and scanning interval, and the speed scanning interval and scanning interval, and calculating the optimized superposition amplitude corresponding to each set of scanning time and speed using a two-dimensional window correlation analysis technique;

[0040] S106 , drawing a refracted wave velocity spectrum based on the optimized superposition amplitude, and obtaining a scanning speed corresponding to a maximum value of the refracted wave velocity spectrum as a target refracted wave velocity.

[0041] Seismic exploration shot records mainly contain wave groups such as direct waves, refracted waves, reflected waves, and surface waves. This application provides a refracted wave velocity picking method that improves the existing linear scanning (τ-p transformation) method and introduces a two-dimensional window based on time and channel number. The window linear scanning is performed by sliding the two-dimensional window and performing correlation analysis to obtain optimized superposition amplitude, effectively filtering out interference waveforms with low similarity, thereby accurately extracting the refracted wave velocity. It has strong anti-interference ability and can be used not only to extract the first-arrival refracted wave velocity, but also to extract the subsequent-arrival refracted wave velocity, strongly supporting the application of refracted wave seismic exploration.

[0042] In step S101 , a single shot record of seismic exploration is obtained.

[0043] A single shot record is a signal sequence generated by multiple underground receivers (seismometers) in seismic exploration, when seismic waves generated by a single excitation (such as a dynamite explosion or the vibration of a vibrator) are captured. The signal received by each receiver constitutes a seismic trace, and the collection of seismic traces constitutes a single shot record. In one embodiment, a single shot record u(n,t) is obtained, where n is the number of seismic recording channels, the total number of channels is Channels, the trace spacing is Δd, and the trace spacing unit is meters; t is the seismic trace recording time, the total length of the seismic trace recording is length, and the sampling interval is Δt, and the sampling interval unit is milliseconds.

[0044] In actual construction applications, receiving traces are laid out along a straight line on the ground. In this embodiment, the shot point location is set as the first trace, and the blank area between the actual first trace location and the shot point location is virtually divided according to the trace spacing Δd, forming a continuous virtual trace sequence. This maintains trace number continuity during data processing. For example, if the actual first trace location and the shot point location are separated by 3Δd, the shot point location is set as the first trace. Based on the spacing between the actual first trace location and the shot point location, the actual first trace location is changed to the fourth trace, thereby reordering the trace numbers.

[0045] This application deploys a seismic exploration observation system based on the depth of the target bottom layer (geological body) to obtain seismic exploration single-shot records containing refracted waves. The farthest receiving point of observation is sufficiently far from the shot point spacing to ensure that the refracted waves have sufficient space to form and be received by the receiver. The single-shot record diagram formed by each channel of seismic exploration data records the relationship between propagation distance and propagation time, which is used to perform window linear scanning to extract the refracted wave velocity.

[0046] In step S102, according to the single shot record, a time scan interval, a time scan interval, a speed scan interval, and a speed scan interval are set. Step S102 includes:

[0047] According to the seismic exploration single shot record, the shot point position of the single shot record is used as the first track, the shot point excitation time is used as the initial recording time, and the time scanning interval, velocity scanning interval, time scanning interval and velocity scanning interval are set.

[0048] In this embodiment, according to the single-shot record, the shot point position of the single-shot record is taken as the first track to obtain the total number of tracks in the single-shot record map; the shot point excitation time is taken as the initial recording time 0s to obtain the recording duration of the single-shot record; and according to the total number of tracks and the recording duration, the time scan interval, time scan interval, speed scan interval, and speed scan interval are set.

[0049] The time scan interval is the single shot recording time of seismic exploration, and the time scan interval is adjusted according to the time scan interval and actual needs. In one embodiment, the shot point excitation time is the initial recording time: 0s, and the time scan interval is (τ1~τ2).

[0050] In one embodiment, the velocity scanning interval (v1-v2) includes the seismic wave velocity range of the rocks and formations in the target working area. For example, the velocity scanning interval is set to 500-5000 m / s. In other embodiments, it can also be adjusted according to the purpose of seismic exploration. The velocity scanning interval is adjusted according to actual needs. In some embodiments, it can be 1 / 100-1 / 20 of the scanning speed, such as 5 m / s, 10 m / s, 20 m / s, 50 m / s, etc.

[0051] In this embodiment, the time scanning interval and velocity scanning interval are set according to the observation time of the single shot record and the velocity range of the seismic wave, and the time scanning interval and velocity scanning interval are set according to the actual requirements of the refracted wave, so as to scan the trace data recorded by the single shot and extract the refracted wave velocity.

[0052] In step S103, a time-channel two-dimensional window is introduced, and the time width, number of channels, and window movement interval of the time-channel two-dimensional window are set according to the scanning time and the scanning speed. Step S103 includes:

[0053] According to the preset scanning time, set the time length of the time-channel two-dimensional window, the window start time and the end time; set the number of channels of the time-channel two-dimensional window, the start channel and the end channel, and set the number of channels of the time-channel two-dimensional window each time.

[0054] In seismic exploration, the refracted waves in seismic waves are distributed linearly, and the time-distance curve of the refracted waves can be represented by a straight line with a certain intercept time. Based on the single-shot recording diagram and the linear distribution of the refracted waves, a time-channel two-dimensional window is introduced.

[0055] The time-channel two-dimensional window is expressed as:

[0056]

[0057] Wherein, the time length of the time-track two-dimensional window is T = t2 - t1, t1 is the window start time, and t2 is the window end time; the number of tracks in the time-track two-dimensional window is N = n2 - n1 + 1, n1 is the window start track number, n2 is the window end track number, and the track spacing between tracks is Δd.

[0058] In one embodiment, a single shot record of seismic exploration is a collection of trace records starting with the shot point position. The observation distance x of the single shot record can be expressed as: x = Δd × (n-1), where Δd is the trace spacing and n is the number of traces. Therefore, the distance width of the time-trace two-dimensional window can be expressed as x2-x1, where x1 and x2 are the starting position and ending position of the two-dimensional window, respectively, that is, it can be expressed as Δd × (n2-n1), where n1 and n2 are the record trace numbers corresponding to the starting position and ending position of the two-dimensional window, respectively. Therefore, the number of traces N in the time-trace two-dimensional window is n2-n1+1.

[0059] In this application, the time width and length channels of the time-channel two-dimensional window are set according to the single shot record and actual needs. The setting of the time-channel two-dimensional window affects the extraction and analysis effect of the local characteristics of the seismic wave.

[0060] In step S104, a two-dimensional window correlation analysis technique is used to slide the time-channel two-dimensional window according to the window movement interval to obtain multiple time-channel two-dimensional scanning windows. Window correlation analysis is performed on each of the time-channel two-dimensional scanning windows to calculate the optimized superposition amplitude of the time-channel two-dimensional scanning windows corresponding to the scanning time and the scanning speed. In one embodiment, step S104 includes:

[0061] The scanning time and scanning speed are selected in sequence to set the time-channel two-dimensional window.

[0062] Without changing the time length and number of channels of the time-channel two-dimensional window, the time position of the time-channel two-dimensional window in the single-shot record is adjusted according to the selected scan time τ. Based on the selected scan speed, the shape of the time-channel two-dimensional window is changed at a slope corresponding to the scan speed. The time-channel two-dimensional window is then slid at a preset window movement interval to obtain multiple time-channel two-dimensional windows.

[0063] In one embodiment, the time range corresponding to each channel and the start and end channels of the time-channel two-dimensional window is expressed as:

[0064]

[0065] Where: τ is the scanning time, T is the time width of the time-channel two-dimensional window, Δd is the channel spacing, v is the scanning speed, n is the recording channel number, n1 and n2 are the recording channel numbers corresponding to the starting position and ending position of the two-dimensional window, respectively.

[0066] The preset window movement interval is set to Δn channels. In one embodiment, the window movement interval is the channel pitch, and the number of channels moved each time Δn = 1. In a set of time-channel two-dimensional windows with fixed scanning time and scanning speed, the number of two-dimensional windows is M = (Channels - N) / Δn + 1, where N is the number of channels in the time-channel two-dimensional window.

[0067] In one embodiment, the single-shot recording has a total number of channels = 200, with channel numbers n = 1, 2, 3, ..., 200, a channel spacing Δd = 5 m, and a recording length = 1000 ms. Each window shift has a channel number Δn = 1, and the total number of two-dimensional windows, M, is 120. Therefore, the total number of two-dimensional windows, N = (Channels - N) / Δn + 1 = (200 - 120) / 1 + 1 = 81.

[0068] Calculating the window linear superposition amplitude corresponding to each two-dimensional window according to the two-dimensional window linear amplitude superposition formula includes the following steps:

[0069] The trace data in each of the time-channel two-dimensional scanning windows are respectively obtained, and the trace data in each of the time-channel two-dimensional scanning windows are respectively input into the following window linear amplitude superposition formula to obtain the window linear superposition amplitude corresponding to each of the windows:

[0070]

[0071] Where m is the serial number of the two-dimensional window, 1≤m≤M, M is the total number of refracted wave scanning segments, A(m) is the linear superposition amplitude of the m-th two-dimensional window segment, u(n,t) is the track data of the refracted wave scanning segment, n1 is the starting track number of the refracted wave scanning segment, n2 is the ending track number of the refracted wave scanning segment, τ is the scanning time, v is the scanning speed, and Δn is the number of tracks moved each time.

[0072] In one embodiment, if the total number of channels of the single shot recording image is 200, when the initial scanning time is t 0R And the scanning speed is v i When the arrival time of each receiving channel is calculated as t i1 , t i2 , t i3 ,……,t i200 , read the amplitude u corresponding to each receiving channel n (n=1, 2, 3,..., 200).

[0073] Calculate the average value of the trace data in each of the time-channel two-dimensional scanning windows to obtain the average value of the trace data in the time-channel two-dimensional scanning window:

[0074]

[0075] Where w(m,t) is the average value of the window channel data, m is the sequence number of the two-dimensional window, u(n,t) is the channel data of the two-dimensional window, n1 is the starting channel number of the two-dimensional window, n2 is the ending channel number of the two-dimensional window, t is the sampling time, v is the scanning speed, and Δn is the number of channels moved each time.

[0076] According to the average value of the trace data, the trace data correlation coefficient of the time-trace two-dimensional scanning window is calculated:

[0077]

[0078] According to the track data correlation coefficient, the average value of the track data correlation coefficient is calculated to obtain the window correlation coefficient:

[0079]

[0080] Where, is the window correlation coefficient, m is the serial number of the refracted wave scanning segment, M is the total number of refracted wave scanning segments, and r(m) is the trace data correlation coefficient.

[0081] The maximum value of the product of the window linear superposition amplitude and the window correlation coefficient is calculated using the window linear superposition amplitude and the window correlation coefficient of each time-channel two-dimensional scanning window to obtain the optimized superposition amplitude A corresponding to the scanning time and scanning speed. r (τ,v):

[0082]

[0083] Where A r (τ,v) is the optimized superposition amplitude, is the window correlation coefficient, and A(m) is the linear superposition amplitude.

[0084] In this embodiment, the window linear stacking amplitude of each time-channel two-dimensional scanning window is calculated using the window linear amplitude stacking formula. A correlation coefficient is calculated based on the channel data of each received channel in the time-channel two-dimensional scanning window and the average value of the channel data. The average value of the correlation coefficient of each channel data in the time-channel two-dimensional scanning window is calculated to obtain a window correlation coefficient. The window correlation coefficient and the window linear stacking amplitude are used to calculate the maximum value of the product of the window correlation coefficient and the window linear stacking amplitude for each time-channel two-dimensional scanning window to obtain an optimized stacking amplitude corresponding to the scanning time and scanning speed.

[0085] In step S105, a time and speed nested loop is performed based on the time scanning interval and scanning interval, and the speed scanning interval and scanning interval, and the optimized superposition amplitude corresponding to each set of scanning time and speed is calculated using a two-dimensional window correlation analysis technique. Step S105 includes:

[0086] According to the scanning time interval (τ1-τ2) and the scanning speed interval (v1-v2), a time and speed nested loop is performed with the time scanning interval Δτ and the speed scanning interval Δv as the variation. A window correlation analysis is performed on each set of scanning time and scanning speed to obtain the optimized superposition amplitude corresponding to all the scanning times and scanning speeds:

[0087]

[0088] Where: τ is the scanning time, (τ1~τ2) is the time scanning interval, v is the scanning speed, and (v1~v2) is the speed scanning interval.

[0089] In this embodiment, the scanning speed is used as the outer loop, the scanning time is used as the inner loop, and the time scanning interval Δτ and the speed scanning interval Δv are used as the variation to perform nested loops to obtain the entire optimized superimposed amplitude; vice versa, the scanning speed is used as the inner loop, and the scanning time is used as the outer loop.

[0090] It should be noted that the step S104 and the step S105 may be executed synchronously or asynchronously. In other embodiments, the order of execution may be swapped, which is not limited here.

[0091] In step S106, based on the optimized superposition amplitude, a refracted wave velocity spectrum is drawn, and the scanning speed corresponding to the maximum value of the refracted wave velocity spectrum is obtained as the target refracted wave velocity. In one embodiment, step S106 includes the following steps:

[0092] S601 , based on the optimized superposition amplitude, plotting a refracted wave velocity spectrum after correlation analysis.

[0093] In one embodiment, plotting the refracted wave velocity spectrum may include the following steps:

[0094] S601a, obtaining the time width of the time-channel two-dimensional window, and calculating the optimized amplitude average value of the optimized superposition amplitude according to the time width.

[0095] The optimized amplitude average value can be expressed in two forms and can be obtained by the following two mean value calculation formulas respectively.

[0096] Formula 1:

[0097]

[0098] Formula 2:

[0099]

[0100] Where: T is the time width of the time-channel two-dimensional window, T = t2-t1

[0101] S601b: Based on the optimized amplitude average value, a refracted wave velocity spectrum is plotted with time τ as the vertical coordinate and velocity v as the horizontal coordinate.

[0102] The refracted wave velocity spectrum can also be plotted with velocity v as the vertical axis and time τ as the horizontal axis. In another embodiment, a three-dimensional spectrum of the refracted wave velocity spectrum can be plotted with time τ as the horizontal axis, velocity v as the horizontal axis, and amplitude A as the vertical axis.

[0103] S602 : Obtain a velocity spectrum energy cluster corresponding to the maximum value of the optimized superposition amplitude in the refracted wave velocity spectrum, and calculate a target refracted wave velocity based on the velocity spectrum energy cluster.

[0104] In one instance, Figure 7 The window correlation analysis refracted wave velocity picking diagram is shown as follows: Figure 7 Figure a shows a single shot record u(n,t), with a total number of channels = 200, receiving channel numbers n = 1, 2, 3, ..., 200, channel spacing Δd = 5 m, the shot point being the first channel n = 1; and record length length = 1000 ms.

[0105] In the example Figure 7 As shown in b two-dimensional window, the two-dimensional window [t,n] sets the distance width (total number of channels) N = 120, the moving channel number Δn = 1, then the total number of two-dimensional windows M = (Channels-N) / Δn+1 = (200-120) / 1+1 = 81; the two-dimensional window [t,n] sets the time width T = 90ms.

[0106] Perform time and velocity linear scanning two-dimensional window correlation analysis on the single shot record u(n,t) to calculate the optimized superposition amplitude A r (τ,v), plot the velocity spectrum Figure 7 c Optimized correlation amplitude velocity spectrum.

[0107] In the example Figure 7 c shows the optimized related velocity spectrum, the two extreme values ​​of P1 and P2 (also known as velocity spectrum energy clusters) and Figure 7 The two dotted lines in d correspond to the refracted waves, and the velocity v corresponding to the two extreme values ​​of P1 and P2 is a =1808m / s,v b =3997m / s, that is:

[0108] The velocity of the first refracted wave v a =1808m / s;

[0109] The velocity of the second refracted wave v b =3997m / s.

[0110] described Figure 7 In the single-shot record u(n,t) shown in a, the second-layer refracted wave group is severely interfered with, and the phase axis appears intermittently, making it difficult to identify. After window correlation analysis, the refracted wave velocity energy group is clear, effectively suppressing the interference wave and improving the refracted wave picking accuracy.

[0111] The present application discloses a refracted wave velocity picking method, which obtains a single-shot record of seismic exploration, sets a time scanning interval, a time scanning interval, a velocity scanning interval, and a velocity scanning interval according to the number of channels and time of the single-shot record, obtains a scanning time set and a scanning velocity set, introduces a time-channel two-dimensional window based on time and channel number, adjusts the scanning position and scanning area of ​​the two-dimensional window by selecting the scanning time and scanning speed, slides the time-channel two-dimensional window to obtain several two-dimensional windows, performs two-dimensional window correlation analysis, eliminates interference from wave groups with low similarity, obtains an optimized stacking amplitude after optimization, obtains a target refracted wave according to the local maximum value of the optimized stacking amplitude, and further calculates the target refracted wave velocity.

[0112] This application provides a method for extracting refracted wave velocity. This method introduces a two-dimensional window of time and channel number, along with correlation analysis techniques. A linear scanning correlation analysis technique based on the two-dimensional window is proposed. This technique performs a sliding window scan on single-shot seismic exploration recordings and filters the waveforms through correlation analysis. The target refracted wave is ultimately obtained and presented as a velocity spectrum. The target refracted wave velocity is then calculated based on the local maximum values ​​on the velocity spectrum. This technique offers strong interference resistance and high analysis accuracy, providing technical support for extracting refracted waves under complex conditions and expanding the application of refracted waves in seismic exploration.

[0113] Second, see Figure 8 , Figure 8 This is a structural diagram of a refracted wave velocity pickup system provided in an embodiment of the present application. The present application provides a refracted wave velocity pickup system, comprising:

[0114] An acquisition module 11 is used to acquire single shot records of seismic exploration;

[0115] A scanning setting module 12 is used to set a time scanning interval, a time scanning interval, a speed scanning interval and a speed scanning interval according to the single shot recording diagram;

[0116] A two-dimensional window module 13 is used to introduce a time-channel two-dimensional window and set the time length, channel number and window movement interval of the time-channel two-dimensional window according to the time scanning interval and the speed scanning interval;

[0117] a two-dimensional window correlation analysis module 14 configured to employ a two-dimensional window correlation analysis technique to slide the time-channel two-dimensional window according to the window movement interval to obtain a plurality of time-channel two-dimensional scanning windows, perform window correlation analysis on each of the time-channel two-dimensional scanning windows, and calculate an optimized superposition amplitude of the time-channel two-dimensional scanning windows corresponding to the scanning time and the scanning speed;

[0118] The speed-time nested loop module 15 performs a time and speed nested loop according to the time scanning interval and scanning interval, and the speed scanning interval and scanning interval, and calculates the optimized superposition amplitude corresponding to each set of scanning time and speed using a two-dimensional window correlation analysis technique;

[0119] The velocity spectrum analysis module 16 is configured to draw a refracted wave velocity spectrum based on the optimized superposition amplitude, and obtain a scanning velocity corresponding to a maximum value of the refracted wave velocity spectrum as a target refracted wave velocity.

[0120] It should be noted that the aforementioned embodiment provides a refracted wave velocity pickup system, and only illustrates the division of the aforementioned functional modules when performing the refracted wave velocity pickup method. In actual applications, the aforementioned functions can be assigned to different functional modules as needed, that is, the internal structure of the device can be divided into different functional modules to complete all or part of the functions described above. The refracted wave velocity pickup system provided in the aforementioned embodiment is used to perform the refracted wave velocity pickup method described in the aforementioned embodiment. Its operating method and principles are the same as those of the refracted wave velocity pickup method described above. That is, the refracted wave velocity pickup system provided in the aforementioned embodiment and the refracted wave velocity pickup method are based on the same concept. The implementation process is detailed in the aforementioned method embodiment and will not be further described here.

[0121] Thirdly, please refer to Figure 9 , Figure 9 The present application provides a computer device structure. The present application provides a computer device 21 comprising a processor 211, a memory 212, and a computer program 213 stored in the memory 212 and executable on the processor 211, such as a refracted wave velocity picking program. When the processor 211 executes the computer program 213, the refracted wave velocity picking method described in the above embodiment can be implemented.

[0122] Fourthly, the present application provides a computer-readable storage medium that can store multiple instructions, which are suitable for the processor to load and execute the method steps of the above-mentioned embodiment. The specific execution process can be found in the specific description of the above-mentioned embodiment, which will not be repeated here.

[0123] Those skilled in the art will appreciate that the embodiments of the present application may be provided as methods, systems, or computer program products. Therefore, the present application may take the form of a complete hardware embodiment, a complete software embodiment, or an embodiment combining software and hardware. Furthermore, the present application may take the form of a computer program product implemented on one or more computer-usable storage media (including but not limited to magnetic disk storage, CD-ROM, optical storage, etc.) containing computer-usable program code.

[0124] The above embodiments are only used to provide a detailed description of the technical solutions of the present application. However, the description of the above embodiments is only used to help understand the methods of the embodiments of the present application and should not be understood as limiting the present application. Any changes or substitutions that can be easily thought of by those skilled in the art should be included in the scope of protection of the embodiments of the present application.

Claims

1. A method for picking up refracted wave velocity, characterized in that: include: Obtain single shot records for seismic surveys; According to the single shot record, a time scan interval, a time scan interval, a speed scan interval and a speed scan interval are set; Introducing a time-channel two-dimensional window, and setting the time width, number of channels, and window movement interval of the time-channel two-dimensional window according to a preset scanning time and a preset scanning speed; Using a two-dimensional window correlation analysis technique, the time-channel two-dimensional window is slid according to the window movement interval to obtain a plurality of time-channel two-dimensional scanning windows. Window correlation analysis is performed on each of the time-channel two-dimensional scanning windows to calculate the optimized superposition amplitude of the time-channel two-dimensional scanning windows corresponding to the scanning time and the scanning speed. Perform time and speed nested loops according to the time scanning interval and scanning interval, and the speed scanning interval and scanning interval, and calculate the optimized superposition amplitude corresponding to each set of scanning time and speed using a two-dimensional window correlation analysis technique; Based on the optimized superposition amplitude, a refracted wave velocity spectrum is drawn, and a scanning speed corresponding to a maximum value of the refracted wave velocity spectrum is obtained as a target refracted wave velocity.

2. The method for picking up refracted wave velocity according to claim 1, characterized in that: According to the single shot record, the time scan interval, time scan interval, speed scan interval and speed scan interval are set, including: According to the seismic exploration single shot record, the shot point position of the single shot record is used as the first track, the shot point excitation time is used as the initial recording time, and the time scanning interval, velocity scanning interval, time scanning interval and velocity scanning interval are set.

3. The method for picking up refracted wave velocity according to claim 1, wherein: The step of setting the time width, number of length channels, and window movement interval of the time-channel two-dimensional window according to the preset scanning time and the preset scanning speed includes: According to the preset scanning time, set the time length, window start time and end time of the time-channel two-dimensional window; set the number of channels, start channel and end channel of the time-channel two-dimensional window, and set the number of channels of each time the time-channel two-dimensional window moves; The time-channel two-dimensional window is expressed as: The time width T of the time-track two-dimensional window is t2-t1, where t1 is the start time and t2 is the end time. The number of tracks in the time-track two-dimensional window is N=n2-n1+1, where n1 is the start track number and n2 is the end track number. The track spacing between tracks is Δd. The distance width of the time-track two-dimensional window is Δd×(n2-n1).

4. The method for picking up refracted wave velocity according to claim 1, wherein: The steps to obtain the optimized stacking amplitude include: According to the time scanning interval, the time scanning interval, the speed scanning interval and the speed scanning interval, a nested loop of time and speed is used, and based on the window movement interval, a time-channel two-dimensional window is slid to obtain a plurality of time-channel two-dimensional scanning windows; performing linear superposition on the time-channel two-dimensional scanning windows to obtain a window linear superposition amplitude of the time-channel two-dimensional scanning windows; Performing correlation analysis on the linearly superimposed amplitude of the window to calculate the window correlation coefficient of the time-channel two-dimensional scanning window; The optimized superposition amplitude of the time-channel two-dimensional scanning window is obtained according to the window linear superposition amplitude and the window correlation coefficient of the time-channel two-dimensional scanning window.

5. The method for picking up refracted wave velocity according to claim 4, characterized in that: The steps for obtaining the linear stack amplitude and window correlation coefficient include: Perform time-channel two-dimensional window linear superposition on the scanning time and scanning speed, and calculate the window linear superposition amplitude: Where m is the serial number of the refracted wave scanning segment, 1≤m≤M, M is the total number of refracted wave scanning segments, A(m) is the linear superposition amplitude of the mth refracted wave scanning segment, u(n,t) is the track data of the refracted wave scanning segment, n1 is the starting track number of the refracted wave scanning segment, n2 is the ending track number of the refracted wave scanning segment, τ is the scanning time, v is the scanning speed, and Δn is the number of tracks moved each time; Calculate the average value of the trace data in each of the time-channel two-dimensional scanning windows to obtain the average value of the trace data in the time-channel two-dimensional scanning window: Where w(m,t) is the average value of the trace data, m is the serial number of the refracted wave scanning segment, u(n,t) is the trace data of the refracted wave scanning segment, n1 is the starting trace number of the refracted wave scanning segment, n2 is the ending trace number of the refracted wave scanning segment, τ is the scanning time, v is the scanning speed, and Δn is the number of traces moved each time; According to the average value of the trace data, the trace data correlation coefficient of the time-trace two-dimensional scanning window is calculated: According to the track data correlation coefficient, the average value of the track data correlation coefficient is calculated to obtain the window correlation coefficient: in, is the window correlation coefficient, m is the serial number of the two-dimensional window, M is the total number of two-dimensional windows, and r(m) is the channel data correlation coefficient.

6. The method for picking up refracted wave velocity according to claim 4, characterized in that: The step of obtaining the optimized superposition amplitude of the time-channel two-dimensional scanning window according to the window linear superposition amplitude and the window correlation coefficient of the time-channel two-dimensional scanning window comprises: The maximum value of the product of the window linear superposition amplitude and the window correlation coefficient is calculated using the window linear superposition amplitude and the window correlation coefficient of each time-channel two-dimensional scanning window to obtain the optimized superposition amplitude A corresponding to the scanning time and scanning speed. r (τ,v), Among them, A r (τ,v) is the optimized superposition amplitude, is the window correlation coefficient, A(m) is the window linear superposition amplitude, τ is the scanning time, and v is the scanning speed.

7. The method for picking up refracted wave velocity according to claim 1, characterized in that: Drawing a refracted wave velocity spectrum based on the optimized superposition amplitude, and obtaining a scanning speed corresponding to a maximum value of the refracted wave velocity spectrum as a target refracted wave velocity, includes: Based on the optimized superposition amplitude, plotting a refracted wave velocity spectrum after correlation analysis; A velocity spectrum energy cluster corresponding to the maximum value of the optimized superposition amplitude in the refracted wave velocity spectrum is obtained, and a target refracted wave velocity is calculated based on the velocity spectrum energy cluster.

8. A refracted wave velocity pickup system, characterized in that: include: An acquisition module is used to obtain single shot records of seismic exploration; A scanning setting module, used to set the time scanning interval, time scanning interval, speed scanning interval and speed scanning interval according to the single shot recording diagram; A two-dimensional window module is used to introduce a time-channel two-dimensional window and set the time width, number of channels and window movement interval of the time-channel two-dimensional window according to a preset scanning time and a preset scanning speed; a two-dimensional window correlation analysis module, configured to employ a two-dimensional window correlation analysis technique to slide the time-channel two-dimensional window according to the window movement interval to obtain a plurality of time-channel two-dimensional scanning windows, perform window correlation analysis on each of the time-channel two-dimensional scanning windows, and calculate an optimized superposition amplitude of the time-channel two-dimensional scanning windows corresponding to the scanning time and the scanning speed; A speed-time nested loop module is used to perform a time and speed nested loop according to the time scanning interval and scanning interval, and the speed scanning interval and scanning interval, and calculate the optimized superposition amplitude corresponding to each set of scanning time and speed using a two-dimensional window correlation analysis technology; The velocity spectrum analysis module is used to draw a refracted wave velocity spectrum based on the optimized superposition amplitude, and obtain a scanning speed corresponding to a maximum value of the refracted wave velocity spectrum as a target refracted wave velocity.

9. A computer device comprising: A processor, a memory, and a computer program stored in the memory and executable on the processor, wherein when the processor executes the computer program, the steps of a refracted wave velocity picking method according to any one of claims 1 to 7 are implemented.

10. A computer-readable storage medium storing a computer program, characterized in that: When the computer program is executed by a processor, the steps of the refracted wave velocity picking method according to any one of claims 1 to 7 are implemented.

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