Scattered wave extraction method and device

Abstract

The invention provides a scattered wave extraction method and device. The method comprises the steps of a, acquiring a to-be-measured seismic data volume; b, based on a preset separation coefficient calculation formula, a separation coefficient is calculated according to the to-be-measured seismic data volume; c, based on a preset modal decomposition calculation formula, according to the to-be-measured seismic data volume and the separation coefficient, calculating a decomposition data volume; step d, based on a preset signal extraction calculation formula, extracting a first signal according to the to-be-measured seismic data volume, the separation coefficient and the decomposition data volume; step e, repeatedly executing the step b to the step d for multiple times, and sequentially extracting a second signal; and f, based on a preset scattered wave data volume calculation formula, according to the to-be-measured seismic data volume, the first signal and the second signal, calculating a scattered wave data volume.

Description

Technical Field

[0001] The present invention relates to the technical field of geophysical exploration, and particularly to a method and device for extracting scattered waves. Background Art

[0002] When seismic waves propagate underground and encounter discontinuous geological bodies, such as undulating strata, faults, karst caves, fractures, and heterogeneous special abnormal geological bodies, the seismic waves will undergo a scattering effect and generate seismic scattered waves. Utilizing seismic scattered waves can help us identify some special abnormal geological bodies.

[0003] Traditional seismic scattered wave extraction methods utilize the characteristics of scattered waves and other waves on the time-distance curve. After extracting the scattered waves, the imaging of abnormal geological bodies is achieved through the imaging of the scattered wave field. However, this method can only extract scattered waves that can produce obvious differences in the time-distance curve, such as faults and karst caves, and cannot well extract all the characteristics of scattered waves. Summary of the Invention

[0004] Based on this, it is necessary to provide a method and device for extracting scattered waves for the above technical problems.

[0005] A method for extracting scattered waves includes:

[0006] Step a, obtaining a to-be-detected seismic data volume;

[0007] Step b, calculating a separation coefficient based on a preset separation coefficient calculation formula according to the to-be-detected seismic data volume;

[0008] Step c, calculating a decomposed data volume based on a preset modal decomposition calculation formula according to the to-be-detected seismic data volume and the separation coefficient;

[0009] Step d, extracting a first signal based on a preset signal extraction calculation formula according to the to-be-detected seismic data volume, the separation coefficient, and the decomposed data volume;

[0010] Step e, repeatedly executing steps b to d multiple times to sequentially extract second signals;

[0011] Step f, calculating a scattered wave data volume based on a preset scattered wave data volume calculation formula according to the to-be-detected seismic data volume, the first signal, and the second signals.

[0012] In one embodiment, step a, the step of obtaining a to-be-detected seismic data volume includes:

[0013] Obtaining an original seismic data volume, and separating the original seismic data volume according to the offset to obtain the to-be-detected seismic data volume.

[0014] In one embodiment, after step f, which is to calculate the scattered wave data volume based on a preset scattered wave data volume calculation formula according to the to-be-detected seismic data volume, the first signal, and the second signal, the following steps are included:

[0015] Synthesize the scattered wave field according to the scattered wave data volume corresponding to each offset.

[0016] In one embodiment, step f, which is to calculate the scattered wave data volume based on a preset scattered wave data volume calculation formula according to the to-be-detected seismic data volume, the first signal, and the second signal, includes:

[0017] Step f1: Obtain a preset serial number threshold.

[0018] Step f2: When the signal order is less than the preset serial number threshold, superimpose the first signal and the second signal corresponding to the signal order to obtain the main signal component, where the signal order is the serial number set for the first signal and each second signal according to the order of signal output.

[0019] Step f3: When the signal order is greater than or equal to the preset serial number threshold, superimpose the second signals corresponding to the signal order to obtain the secondary signal component.

[0020] Step f4: Calculate the scattered wave data volume based on the preset scattered wave data volume calculation formula according to the to-be-detected seismic data volume, the main signal component, and the secondary signal component.

[0021] In one embodiment, step b, which is to calculate the separation coefficient based on a preset separation coefficient calculation formula according to the to-be-detected seismic data volume, includes:

[0022] Step b1: Analyze the to-be-detected seismic data volume based on Fourier transform to obtain the seismic frequency band width.

[0023] Step b2: Calculate the data volume envelope according to the to-be-detected seismic data volume based on Hilbert transform and the seismic frequency band width.

[0024] Step b3: Calculate the separation coefficient based on the preset separation coefficient calculation formula according to the maximum and minimum values of the data volume envelope.

[0025] An extraction device for scattered waves includes:

[0026] To-be-detected data acquisition module: Used to execute step a to obtain the to-be-detected seismic data volume.

[0027] Separation coefficient calculation module: Used to execute step b to calculate the separation coefficient based on a preset separation coefficient calculation formula according to the to-be-detected seismic data volume.

[0028] Decomposition data calculation module: used to execute step c, based on a preset modal decomposition calculation formula, calculate the decomposition data volume according to the seismic data volume to be measured and the separation coefficient;

[0029] First signal extraction module: used to execute step d, based on a preset signal extraction calculation formula, extract the first signal according to the seismic data volume to be measured, the separation coefficient, and the decomposition data volume;

[0030] Second signal extraction module: used to execute step e, repeatedly execute steps b to d multiple times, and extract the second signal in sequence;

[0031] Scattering data calculation module: used to execute step f, based on a preset scattered wave data volume calculation formula, calculate the scattered wave data volume according to the seismic data volume to be measured, the first signal, and the second signal.

[0032] In one embodiment, the device further includes:

[0033] Seismic data to be measured acquisition module: used to acquire the original seismic data volume, and separate the original seismic data volume according to the offset to obtain the seismic data volume to be measured.

[0034] In one embodiment, the device further includes:

[0035] Wavelength synthesis module: used to synthesize the scattered wave field according to the scattered wave data volume corresponding to each offset.

[0036] A computer device includes a memory and a processor, the memory stores a computer program, and is characterized in that when the processor executes the computer program, the following steps are implemented:

[0037] Step a, acquire the seismic data volume to be measured;

[0038] Step b, based on a preset separation coefficient calculation formula, calculate the separation coefficient according to the seismic data volume to be measured;

[0039] Step c, based on a preset modal decomposition calculation formula, calculate the decomposition data volume according to the seismic data volume to be measured and the separation coefficient;

[0040] Step d, based on a preset signal extraction calculation formula, extract the first signal according to the seismic data volume to be measured, the separation coefficient, and the decomposition data volume;

[0041] Step e, repeatedly execute steps b to d multiple times, and extract the second signal in sequence;

[0042] Step f, based on a preset scattered wave data volume calculation formula, calculate the scattered wave data volume according to the seismic data volume to be measured, the first signal, and the second signal.

[0043] A computer-readable storage medium, on which a computer program is stored, and when the computer program is executed by a processor, the following steps are implemented:

[0044] Step a, obtaining a seismic data volume to be measured;

[0045] Step b, calculating a separation coefficient based on a preset separation coefficient calculation formula according to the seismic data volume to be measured;

[0046] Step c, calculating a decomposed data volume based on a preset modal decomposition calculation formula according to the seismic data volume to be measured and the separation coefficient;

[0047] Step d, extracting a first signal based on a preset signal extraction calculation formula according to the seismic data volume to be measured, the separation coefficient, and the decomposed data volume;

[0048] Step e, repeatedly executing steps b to d multiple times to sequentially extract second signals;

[0049] Step f, calculating a scattered wave data volume based on a preset scattered wave data volume calculation formula according to the seismic data volume to be measured, the first signal, and the second signal.

[0050] In the above method and device for extracting scattered waves, step a is to obtain a seismic data volume to be measured; step b is to calculate a separation coefficient based on a preset separation coefficient calculation formula according to the seismic data volume to be measured; step c is to calculate a decomposed data volume based on a preset modal decomposition calculation formula according to the seismic data volume to be measured and the separation coefficient; step d is to extract a first signal based on a preset signal extraction calculation formula according to the seismic data volume to be measured, the separation coefficient, and the decomposed data volume; step e is to repeatedly execute steps b to d multiple times to sequentially extract second signals; step f is to calculate a scattered wave data volume based on a preset scattered wave data volume calculation formula according to the seismic data volume to be measured, the first signal, and the second signal. With such a design, the seismic data volume to be measured can be decomposed into multiple scattered wave data volumes with different frequencies and different forms through the preset modal decomposition calculation formula, and these scattered wave data volumes can restore the original seismic signal. Therefore, through the preset modal decomposition calculation formula, scattered waves of geological structures other than faults and karst caves can be extracted, that is, scattered waves with no obvious difference in travel-time curves can be extracted, and all scattered wave characteristics can be well extracted. Description of the Drawings

[0051] Figure 1 It is a schematic flowchart of a method for extracting scattered waves in an embodiment;

[0052] Figure 2 It is a structural block diagram of a device for extracting scattered waves in an embodiment;

[0053] Figure 3Internal structure diagram of a computer device in an embodiment;

[0054] Figure 4 Technical flow chart for the extraction of scattered waves in an embodiment;

[0055] Figure 5a Schematic diagram of the pre-separation seismic wave field in an embodiment;

[0056] Figure 5b Schematic diagram of the post-separation seismic wave field in an embodiment;

[0057] Figure 6 Seismic wave field at multiple offsets (left) and the obtained scattered wave field after separation (right);

[0058] Figure 7 Curve graph of the normalized seismic wave field energy amplitude values obtained after separation with different thresholds in an embodiment. Detailed implementation manners

[0059] In order to make the objectives, technical solutions and advantages of the present application clearer, the present application will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present application and are not used to limit the present application.

[0060] Embodiment 1

[0061] In this embodiment, as Figure 1 shown, a method for extracting scattered waves is provided, which includes:

[0062] Step 110, obtaining a to-be-measured seismic data volume.

[0063] In this embodiment, the to-be-measured seismic data volume includes seismic wave data at different position points and different times on a plane. The to-be-measured seismic data volume contains reflected wave data and can be used as a data source for extracting reflected waves.

[0064] Step 120, calculating a separation coefficient according to the to-be-measured seismic data volume based on a preset separation coefficient calculation formula.

[0065] In this embodiment, since modal decomposition requires a separation coefficient, in this step, a Hilbert transform is performed on the to-be-measured seismic data volume to obtain a Hilbert data volume. The to-be-measured seismic data volume and the Hilbert data volume are input into a calculation formula for the data volume envelope to obtain the data volume envelope. The numerical values of the data volume envelope have multiple values in this embodiment. According to the maximum value and the minimum value of the data volume envelope, the separation coefficient is calculated.

[0066] Step 130: Calculate the decomposed data volume based on the preset modal decomposition calculation formula according to the seismic data volume to be measured and the separation coefficients.

[0067] In this embodiment, perform modal decomposition on the seismic data volume to be measured, input the seismic data volume to be measured and the separation coefficients into the preset modal decomposition calculation formula, and multiple decomposed data volumes can be obtained. Among them, the number of decomposed data volumes can be adjusted by artificially setting parameters.

[0068] Step 140: Extract a signal as the first signal based on the preset signal extraction calculation formula according to the seismic data volume to be measured, the separation coefficients, and the decomposed data volume.

[0069] In this embodiment, in order to extract the scattered waves more accurately, extract the main component signal from the seismic data volume to be measured through the preset signal extraction calculation formula to obtain the first signal, and the separation coefficients and the decomposed data volume are used as parameters in the extraction process.

[0070] Step 150: Repeatedly execute Step 120 to Step 140 multiple times, and sequentially extract signals as the second signals.

[0071] In this embodiment, in order to continue to extract the signals of other components in the seismic data volume to be measured, repeat the calculation of the separation coefficients, the calculation of the decomposed data volume, and the signal extraction. It should be understood that the signals extracted in this step are used as the second signals, and the signals extracted in Step 140 are used as the first signals. Since Step 150 is repeated multiple times, multiple second signals can be obtained. Each time the calculation is repeated, a second signal is obtained, and the second signals are output sequentially, and serial numbers are set for the second signals according to the order of acquisition.

[0072] Step 160: Calculate the scattered wave data volume based on the preset scattered wave data volume calculation formula according to the seismic data volume to be measured, the first signal, and the second signals.

[0073] In this embodiment, sum the first signal and the second signals in groups. Group them according to the order of output of the first signal and the second signals. Take the first signal and the second signal output earlier as a group, which is used as the main component for calculating the scattered wave data volume, and the subsequent second signals are used as another group, which is used as the secondary component for calculating the scattered wave data volume.

[0074] In the method for extracting scattered waves in this embodiment, through step 110, the seismic data volume to be measured is obtained; in step 120, based on a preset separation coefficient calculation formula, the separation coefficient is calculated according to the seismic data volume to be measured; in step 130, based on a preset modal decomposition calculation formula, the decomposed data volume is calculated according to the seismic data volume to be measured and the separation coefficient; in step 140, based on a preset signal extraction calculation formula, the first signal is extracted according to the seismic data volume to be measured, the separation coefficient, and the decomposed data volume; in step 150, steps 120 to 140 are repeatedly executed multiple times to sequentially extract the second signal; in step 160, based on a preset scattered wave data volume calculation formula, the scattered wave data volume is calculated according to the seismic data volume to be measured, the first signal, and the second signal. With such a design, the seismic data volume to be measured can be decomposed into multiple scattered wave data volumes with different frequencies and different forms through the preset modal decomposition calculation formula, and these scattered wave data volumes can restore the original seismic signal. Therefore, through the preset modal decomposition calculation formula, the scattered waves of geological structures other than faults and karst caves can be extracted, that is, the scattered waves with no obvious difference in travel-time curves can be extracted, and all the scattered wave characteristics can be well extracted.

[0075] It should be understood that although Figure 1 the steps in the flowchart of Figure 1 are shown in sequence according to the indication of the arrows, these steps do not necessarily need to be executed in the order indicated by the arrows. Unless otherwise clearly stated in this article, the execution of these steps has no strict order limit, and these steps can be executed in other orders. Moreover,

[0076] Embodiment 2

[0077] In this embodiment, a method for extracting scattered waves is provided, which includes:

[0078] Step 1: Obtain the original seismic data volume, and separate the original seismic data volume according to the offset to obtain the seismic data volume to be measured.

[0079] In this embodiment, the original seismic data volume D shot (x, y, t, h) includes seismic data with different offset distances h, that is, it includes the seismic data volume to be measured D shot (x, y, t) with different offset distances. Therefore, the original seismic data volume can be divided according to the offset distance h to obtain several data volumes D shot (x, y, t), and this data volume Dshot (x, y, t) is the seismic data volume to be measured.

[0080] Step 2: Based on the Fourier transform, analyze the seismic data volume to be measured to obtain the seismic frequency band width.

[0081] In this embodiment, the Fourier transform means that a certain function satisfying certain conditions can be represented as a linear combination of trigonometric functions (sine and / or cosine functions) or integrals of trigonometric functions. The purpose of the Fourier transform is to transform the signal in the time domain into a signal in the frequency domain. With the transformation of the domain, the seismic frequency band width can be analyzed from the signal in the frequency domain, and the upper limit f h and the lower limit f l of the seismic frequency band can be determined. In this embodiment, there are multiple seismic data volumes to be measured, and the offset distances h of different seismic data volumes to be measured are different. It is necessary to perform Fourier transforms on the seismic data volumes to be measured with different offset distances h respectively, so as to obtain the seismic frequency band width.

[0082] In one embodiment, the Fourier transform is performed on the seismic data volume to be measured according to a preset time window size and lateral width. In this embodiment, in order to flexibly process the seismic data volume to be measured in different situations, the Fourier transform is performed on different seismic data to be measured by setting the preset time window size and lateral width, so that the parameters in the Fourier transform can be flexibly adjusted to flexibly handle the seismic data volume to be measured in different situations. Among them, the lateral width refers to the number of seismic traces selected. For example, if one trace is selected, it is one-dimensional data Dshot(1, 1, t), and if three traces are selected, it is three-dimensional data Dshot(x, y, t). After performing the Fourier transform on the seismic data volume to be measured, the seismic frequency band width will be obtained. Analyzing the frequency band width is used to determine the range from the low frequency fl (i.e., the lower limit f l ) to the high frequency fh (i.e., the upper limit f h ) of the frequency band. The low frequency fl and high frequency fh of the seismic frequency are used to determine the Hilbert transform of the data volume.

[0083] Step 3: Based on the Hilbert transform and the seismic frequency band width, calculate the data volume envelope according to the seismic data volume to be measured.

[0084] In this embodiment, the lower limit f l and the upper limit f h obtained in Step 2 are used to perform the Hilbert transform on the seismic data volume to be measured, and the obtained result is used as the Hilbert data volume. If there is no lower limit f l and upper limit f h , then Dshot(x, y, t) will be decomposed into countless sub-signals. The lower limit f l and the upper limit f hUsed to determine the calculation range of the Hilbert transform. Then, based on the preset envelope calculation formula, the data volume envelope e is calculated according to the Hilbert data volume and the seismic data volume to be measured.

[0085] In one embodiment, the Hilbert transform is performed on the seismic data volume to be measured to obtain the Hilbert data volume; based on the preset envelope calculation formula, the data volume envelope is calculated according to the Hilbert data volume and the seismic data volume to be measured. In this embodiment, the lower limit f l and the upper limit f h of the seismic frequency band are used to perform the Hilbert transform on the seismic data volume to be measured to obtain the Hilbert data volume D shot(H) 2 (x, y, t), and then the Hilbert data volume and the seismic data volume to be measured are input into the preset envelope calculation formula to calculate the data volume envelope. There can be multiple data volume envelopes, and the maximum value e max and the minimum value e min of the data volume envelope can be determined, which is prepared for the next step of calculating the separation coefficient.

[0086] In one embodiment, the preset envelope calculation formula is shown in Equation (1):

[0087]

[0088] In Equation (1), e is the data volume envelope, and D shot(H) 2 (x, y, t) is the Hilbert data volume, and D shot (x, y, t) is the seismic data volume to be measured.

[0089] Step four, based on the preset separation coefficient calculation formula, calculate the separation coefficient according to the maximum and minimum values of the data volume envelope.

[0090] In this embodiment, the preset separation coefficient calculation formula is constructed with reference to the modal decomposition formula, and the maximum value e max and the minimum value e min of the data volume envelope are used to calculate the separation coefficient δ(x, y, t).

[0091] In one embodiment, the preset separation coefficient calculation formula is shown in Equation (2):

[0092]

[0093] In Equation (2), δ(x, y, t) is the separation coefficient, e max is the maximum value of the data volume envelope, and e min is the minimum value of the data volume envelope.

[0094] Step 5: Based on the preset modal decomposition calculation formula, calculate the decomposed data volume according to the to-be-detected seismic data volume and the separation coefficient.

[0095] In this embodiment, the preset modal decomposition calculation formula is the functional relationship among the separation coefficient, the decomposed data volume, and the to-be-detected seismic data volume. Since the separation coefficient and the to-be-detected seismic data volume are obtained in the previous steps, the separation coefficient and the to-be-detected seismic data volume can be input into the preset modal decomposition calculation formula to calculate the decomposed data volume.

[0096] In one embodiment, the preset modal decomposition calculation formula is shown in Equation (3):

[0097]

[0098] In Equation (3), D shot (x, y, t) is the to-be-detected seismic data volume, δ k (x, y, t) is the separation coefficient, and IMF k (x, y, t) is the data volume obtained after decomposition, i.e., the decomposed data volume, and k is the number of decompositions.

[0099] Step 6: Based on the preset signal extraction calculation formula, extract the first signal according to the to-be-detected seismic data volume, the separation coefficient, and the decomposed data volume.

[0100] In this embodiment, based on the principle of obtaining a new signal by subtracting the decomposed signal from the original signal, a preset signal extraction calculation formula is constructed. Subtract the decomposed data volume obtained by decomposition from the to-be-detected seismic data volume to obtain the new signal, i.e., the first signal. Among them, there may be multiple decomposed data volumes, and there may also be multiple separation coefficients. Corresponding the decomposed data volumes and the separation coefficients, multiplying the corresponding decomposed data volumes and separation coefficients, and subtracting the product of the multiplication between each pair of decomposed data volumes and separation coefficients from the to-be-detected seismic data volume to obtain the first signal.

[0101] In one embodiment, the preset signal extraction calculation formula is shown in Equation (4):

[0102] r 1 (x, y, t) = D shot (x, y, t) - δ 1 (x, y, t) * IMF 1 (x, y, t) (4)

[0103] In Equation (4), r 1 (x, y, t) is the first signal, D shot (x, y, t) is the to-be-detected seismic data volume, δ 1 (x, y, t) is the separation coefficient, and IMF 1 (x, y, t) is the decomposed data volume.

[0104] Step 7: Repeat Steps 4 to 6 multiple times to sequentially extract the second signal.

[0105] In this embodiment, rk(x, y, t) output in Step 6 serves as the data body in Step 4, and after performing the Hilbert transform on it, the data body D after the Hilbert transform is obtained. shot(H) 2 , and then calculate the envelope e of the data body. By repeating Steps 4 to 6, the second signals r 2 (x, y, t), r 3 (x, y, t),..., r n (x, y, t) are sequentially extracted.

[0106] In one embodiment, detect the number of times Steps 4 to 6 are repeatedly executed currently; when the number of repetitions reaches the preset number of repetitions, stop the extraction of the second signal. In this embodiment, to reduce the computational amount and avoid over-extracting the second signal, the number of repetitions of Step 7 is restricted. When the number of repetitions is reached, stop the step of obtaining the second signal to reduce the amount of computation.

[0107] Step 8: Calculate the scattered wave data body based on the preset scattered wave data body calculation formula according to the to-be-detected seismic data body, the first signal, and the second signal.

[0108] In this embodiment, group and sum the first signal and the second signals. Group them in the order of signal output, and set signal orders for the first signal and each second signal according to the order of output. For example, set the signal order of the first signal to 1, the signal order of the first obtained second signal to 2, and so on. The signal order of the second signal with a later output time is larger.

[0109] In one embodiment, the step of calculating the scattered wave data body based on the preset scattered wave data body calculation formula according to the to-be-detected seismic data body, the first signal, and the second signal includes:

[0110] Step f1: Obtain the preset serial number threshold;

[0111] Step f2: When the signal order is less than the preset serial number threshold, superimpose the first signal and the second signal corresponding to the signal order to obtain the main signal component, where the signal order is the serial number set for the first signal and each second signal according to the order of signal output;

[0112] Step f3: When the signal order is greater than or equal to the preset serial number threshold, superimpose the second signal corresponding to the signal order to obtain the secondary signal component;

[0113] Step f4: Calculate the scattered wave data volume according to the measured seismic data volume, the main signal component, and the secondary signal component based on the preset scattered wave data volume calculation formula.

[0114] In this embodiment, the preset serial number threshold is used to group the first signal and the second signal. The first signal and the second signal with a signal order less than the preset serial number threshold are grouped together, and the main signal component is obtained by superimposing the signals in this group. The second signal with a signal order greater than or equal to the preset serial number threshold is grouped alone, and the secondary signal component is obtained by superimposing the signals in this group. Then, the main signal component and the secondary signal component are input into the preset scattered wave data volume calculation formula to obtain the scattered wave data volume.

[0115] In one embodiment, the main signal component is shown in Equation (5):

[0116]

[0117] In Equation (5), D main (x, y, t) is the main signal component, and r k (x, y, t) is the first signal or the second signal. When k = 1, r k (x, y, t) is the first signal. When k > 1, r k (x, y, t) is the second signal.

[0118] In one embodiment, the secondary signal component is shown in Equation (6):

[0119]

[0120] In Equation (6), D res (x, y, t) is the secondary signal component, and r k (x, y, t) is the second signal, where k > 1.

[0121] In one embodiment, the preset scattered wave data volume calculation formula is shown in Equation (7):

[0122] D diff (x, y, t) = 0.5 * (D shot (x, y, t) - D main (x, y, t)) + 0.5 * D res (x, y, t) (7)

[0123] In Equation (7), D diff (x, y, t) is the scattered wave data volume, D shot (x, y, t) is the measured seismic data volume, D main (x, y, t) is the main signal component, and D res (x, y, t) is the secondary signal component.

[0124] In another embodiment, the preset scattered wave data volume calculation formula can also be as shown in Equation (8):

[0125] D diff (x, y, t) = D shot (x, y, t) - D res (x, y, t) (8)

[0126] In Equation (8), D diff (x, y, t) is the scattered wave data volume, D shot (x, y, t) is the seismic data volume to be measured, and D res (x, y, t) is the secondary signal component.

[0127] Step Nine: Synthesize the scattered wave field according to the scattered wave data volume corresponding to each offset.

[0128] In this embodiment, since the above steps calculate the seismic data volume to be measured corresponding to different offsets respectively, the obtained scattered wave data volume D diff (x, y, t) is obtained. In order to more vividly display the scattered wave situation in this geological area, the scattered wave data volumes calculated from the seismic data volumes to be measured with different offsets are synthesized to obtain the scattered wave field, so as to observe the scattered waves in this area from a macroscopic perspective.

[0129] Embodiment Three

[0130] In this embodiment, a method for extracting scattered waves is provided, which includes:

[0131] First, execute Step One:

[0132] The original seismic data is separated into seismic data with different offsets h according to the offset. First, the actually collected original seismic data D shot (x, y, t, h) is divided into several data volumes D shot (x, y, t) according to the offset h.

[0133] The seismic data is the data volume D shot (x, y, t), where x and y represent the plane coordinates, and t represents the longitudinal time coordinate.

[0134] Then, execute Step Two:

[0135] For the data volume D shot (x, y, t) with different offsets, analyze the frequency band width of the seismic data, set the time window and the horizontal width of the analysis size, perform Fourier transform on the seismic data, and generate the frequency spectrum of the seismic data. Set the lower limit f l and the upper limit fh h is obtained from the offset information recorded during the acquisition of the original seismic data volume. The offset of the data volume Dshot is h described in Step 1. The Fourier transform (FFT) is used to analyze the frequency band width, and the role of analyzing the frequency band width is to determine the range from the low frequency fl to the high frequency fh of the frequency band. The lateral width refers to the number of selected seismic traces. If only one trace is selected, it is the one-dimensional data Dshot(1,1,t). If multiple traces are selected, it is the three-dimensional data D shot (x,y,t). The obtained seismic frequencies fl and fh are used to determine the Hilbert transform of the data volume.

[0136] Subsequently, perform Step 3:

[0137] Calculate the separation coefficient δ(x,y,t), where e max is the maximum value of the data volume envelope, and e min is the minimum value of the data volume envelope. The calculation formula for e is: D shot(H) 2 (x,y,t) is the Hilbert transform of the data volume. e is the data volume envelope.

[0138] Subsequently, perform Step 4:

[0139] Perform modal decomposition on the data volume D shot (x,y,t). The modal decomposition expression is: where k is the number of decompositions, and IMF k (x,y,t) is the data volume obtained after decomposition, and is the separation coefficient δ(x,y,t). The number of K is determined by a manually set parameter. The size of K has nothing to do with the number of D shot (x,y,t) and depends on the manually set parameter. This formula is used to calculate the data volume IMF k (x,y,t) obtained after decomposition.

[0140] Subsequently, perform Step 5:

[0141] First, mainly extract the signal r 1 (x,y,t), where the process of extracting the signal is r 1 (x,y,t) = D shot (x,y,t) - δ 1 (x,y,t) * IMF 1 (x,y,t), and then repeat Step 3 and Step 4 to sequentially extract the secondary signals r 2 (x,y,t), r 3 (x,y,t),..., r n(x, y, t). The repeating step depends on the output result of the previous time. The output of step five is used as the input of step three and is continuously repeated until the artificially set k value is satisfied.

[0142] Subsequently, execute step six:

[0143] Select a threshold M. When k < M, it is denoted as When k ≥ M, it is denoted as Dmain represents the main component in the signal, Dres represents the residual signal in the signal, M is the critical value defining between the main component and the residual signal, and k is the same as the k described previously.

[0144] Finally, execute step seven:

[0145] Output the scattered wave data volume D at a single offset diff (x, y, t), where the calculation formula is D diff (x, y, t) = 0.5 * (D shot (x, y, t) - D main (x, y, t)) + 0.5 * D res (x, y, t), and synthesize the data volumes of all offsets into a scattered wave field D diff (x, y, t, h). D diff (x, y, t) = 0.5 * (D shot (x, y, t) - D main (x, y, t)) + 0.5 * D res (x, y, t) is determined based on the wave field characteristics of the scattered wave.

[0146] In this embodiment, step one: The original seismic data is separated into seismic data with different offsets according to the offset. First, the original seismic data D shot (x, y, t, h) is divided into several data volumes D shot (x, y, t) according to the offset h;

[0147] Step two: Analyze the frequency band width of the seismic data for the data volume D shot (x, y, t) with different offsets, set the time window and the horizontal width of the analysis size, perform Fourier transform on the seismic data, and generate the frequency spectrum of the seismic data. Set the lower limit f l and the upper limit f h ;

[0148] Step three: Calculate the separation coefficient δ(x, y, t), where e max is the maximum value of the data volume envelope, e minThe minimum value of the data body envelope, and the calculation formula of e is: D shot(H) 2 (x, y, t) is the Hilbert transform of the data body.

[0149] Among them, the calculation formula is constructed with reference to the modal decomposition formula. The Hilbert transform requires the lower limit f l and the upper limit f h . If there is no upper and lower limit, then D shot (x, y, t) will be decomposed into countless sub-signals. The upper and lower limits are used to calculate the range in the Hilbert transform.

[0150] Step Four: Perform modal decomposition on the data body D shot (x, y, t), and the modal decomposition expression is: Among them, n is the total number of decompositions, k is the current number of decompositions, IMF k (x, y, t) is the data body obtained after decomposition, and δ(x, y, t) is the separation coefficient. The modal decomposition technology can theoretically decompose seismic signals into multiple seismic signals with different frequencies and different forms. After superimposing these signals, the original seismic signal can be restored. Therefore, it can be said that modal decomposition can extract all seismic signals.

[0151] Step Five: First, mainly extract the signal r 1 (x, y, t), and the process of extracting the signal is r 1 (x, y, t) = D shot (x, y, t) - δ 1 (x, y, t) * IMF 1 (x, y, t), and then repeat Step Three and Step Four to extract secondary signals r 2 (x, y, t), r 3 (x, y, t),..., r n (x, y, t). r 1 (x, y, t) = D shot (x, y, t) - δ 1 (x, y, t) * IMF 1 (x, y, t). The construction principle is to subtract the decomposed signal from the original signal to obtain a new signal.

[0152] The r k (x, y, t) output in Step Five is used as the data body in Step Three, and the Hilbert transform is performed to obtain the data body D shot(H) 2 (x, y, t) after the Hilbert transform, and then calculate

[0153] δ k (x, y, t) belongs to the sub - terms of δ(x, y, t). Starting from k = 1, k is continuously increased to n, and for each calculation of the k - value. The first term is the set of the second - term formula. Each δ k (x, y, t) is obtained by one - time decomposition.

[0154] Step six: Select the threshold M. When k < M, denote it as When k ≥ M, denote it as

[0155] where, r k (x, y, t) not only represents the magnitude of the signal value but also has phase information. Summing r k (x, y, t) respectively is to add up the signals of different components to form a signal with the characteristics of the scattered - wave field.

[0156] Step seven: Output the scattered - wave data volume D diff (x, y, t), where the calculation formula is D diff (x, y, t) = D shot (x, y, t) - D res (x, y, t). Combine the data volumes of all offsets into a scattered - wave field D diff (x, y, t, h).

[0157] In this embodiment, when seismic waves encounter discontinuous geological bodies during underground propagation, such as undulating strata, faults, fractures, vugs, cracks, and heterogeneous and other special abnormal geological bodies, seismic waves will undergo a scattering effect and generate seismic scattered waves. Utilizing seismic scattered waves can help us identify some special abnormal geological bodies. However, due to the fact that during the propagation of seismic scattered waves, the attenuation of the waves is relatively fast. It is very difficult to observe the existence of scattered waves through conventional processing means, which causes difficulties in the interpretation of abnormal geological bodies. Traditional methods for extracting seismic scattered waves use the characteristics of scattered waves and other waves on the travel - time curve. After extracting the scattered waves, the detection of abnormal geological bodies can be achieved. The method of using custom - threshold mode decomposition proposed by the present invention can accurately extract the scattered - wave field from all seismic signals, and the extraction process is stable and controllable.

[0158] See Figure 4, the method for extracting scattered waves in this embodiment includes: obtaining original seismic data, offset-separated data, calculating separation coefficients, performing data modal decomposition, sequentially extracting signals, selecting thresholds, and outputting scattered wave data volumes. That is, it includes: offset arrangement, separation coefficient calculation, modal decomposition, signal combination, wavefield extraction of scattered waves, and offset recombination. The extraction method proposed by the present invention can effectively extract the scattered wavefield from the original seismic data. The extraction process is stable and controllable, and the calculated scattered wavefield is not interfered by other wavefield signals.

[0159] See Figure 5a and Figure 5b , the original seismic wavefield at a single offset and the scattered wavefield obtained after calculation and extraction by the present invention. The original seismic wavefield contains direct waves, reflected waves, and scattered waves. It can be seen from the figure that the present invention can well separate the scattered wavefield from the original wavefield, and there are no remaining other types of seismic waves in the scattered wavefield.

[0160] See Figure 6 , the comparison between the scattered wavefields separated at different offsets and recombined according to the offset set and the original seismic data. It is found from the comparison in the figure that there are no remaining reflected waves and direct waves in the separated scattered wavefield.

[0161] See Figure 7 , showing the normalized seismic energy calculated after recombining the signals after modal decomposition at different thresholds. It can be seen from the curve in the figure that the greater the threshold, the lower the energy of the remaining seismic wavefield obtained after modal decomposition.

[0162] In this embodiment, a new method specifically for extracting the seismic scattered wavefield is proposed: when seismic waves propagate underground and encounter discontinuous geological bodies, the seismic waves will undergo a scattering effect, resulting in the phenomenon of seismic scattered waves. By rearranging the original seismic data according to the offset, at a single offset, using the method of modal decomposition to decompose the seismic signals, calculating the separation coefficients, setting thresholds, recombining the seismic signals, and then calculating the scattered wavefield of the seismic waves according to the formula. The calculation method proposed by the present invention can accurately extract the scattered wavefield from all seismic signals. Compared with traditional methods, the extraction process is stable and controllable.

[0163] Embodiment 4

[0164] In this embodiment, as Figure 2 shown, a device for extracting scattered waves is provided, including:

[0165] Module 210 for obtaining data to be measured: used to execute step 110 to obtain the seismic data volume to be measured;

[0166] Separation coefficient calculation module 220: configured to execute step 120, calculate a separation coefficient based on a preset separation coefficient calculation formula according to the seismic data volume to be measured;

[0167] Decomposed data calculation module 230: configured to execute step 130, calculate a decomposed data volume based on a preset modal decomposition calculation formula according to the seismic data volume to be measured and the separation coefficient;

[0168] First signal extraction module 240: configured to execute step 140, extract a first signal based on a preset signal extraction calculation formula according to the seismic data volume to be measured, the separation coefficient, and the decomposed data volume;

[0169] Second signal extraction module 250: configured to execute step 150, repeatedly execute steps 120 to 140 multiple times to sequentially extract second signals;

[0170] Scattering data calculation module 260: configured to execute step 160, calculate a scattered wave data volume based on a preset scattered wave data volume calculation formula according to the seismic data volume to be measured, the first signal, and the second signal.

[0171] In the scattered wave extraction device of this embodiment, the seismic data volume to be measured is obtained by the data acquisition module 210 for the to-be-measured data to execute step 110; the separation coefficient calculation module 220 is configured to execute step 120, calculate a separation coefficient based on a preset separation coefficient calculation formula according to the seismic data volume to be measured; the decomposed data calculation module 230 is configured to execute step 130, calculate a decomposed data volume based on a preset modal decomposition calculation formula according to the seismic data volume to be measured and the separation coefficient; the first signal extraction module 240 is configured to execute step 140, extract a first signal based on a preset signal extraction calculation formula according to the seismic data volume to be measured, the separation coefficient, and the decomposed data volume; the second signal extraction module 250 is configured to execute step 150, repeatedly execute steps 120 to 140 multiple times to sequentially extract second signals; the scattering data calculation module 260 is configured to execute step 160, calculate a scattered wave data volume based on a preset scattered wave data volume calculation formula according to the seismic data volume to be measured, the first signal, and the second signal. Such a design can decompose the seismic data volume to be measured into multiple scattered wave data volumes with different frequencies and different forms through a preset modal decomposition calculation formula. These scattered wave data volumes can restore the original seismic signal. Therefore, scattered waves of geological structures other than faults and karst caves can be extracted through the preset modal decomposition calculation formula, that is, scattered waves with no obvious difference in travel-time curves can be extracted, and all scattered wave characteristics can be well extracted.

[0172] In one embodiment, the data to be measured acquisition module is configured to acquire the original seismic data volume, separate the original seismic data volume according to the offset, and obtain the seismic data volume to be measured.

[0173] In one embodiment, the apparatus includes a scattered wave field synthesis module configured to synthesize a scattered wave field according to the scattered wave data volumes corresponding to the respective offsets.

[0174] In one embodiment, the scattered data calculation module further includes:

[0175] a threshold sequence number module configured to obtain a preset sequence number threshold;

[0176] a main signal module configured to, when the signal sequence is less than the preset sequence number threshold, superimpose the first signal and the second signals corresponding to the signal sequence to obtain a main signal component, where the signal sequence is a sequence number set for the first signal and each of the second signals in the order of signal output;

[0177] a secondary signal module configured to, when the signal sequence is greater than or equal to the preset sequence number threshold, superimpose the second signals corresponding to the signal sequence to obtain a secondary signal component;

[0178] a scattered wave extraction module configured to calculate the scattered wave data volume according to the seismic data volume to be measured, the main signal component, and the secondary signal component based on the preset scattered wave data volume calculation formula.

[0179] In one embodiment, the separation coefficient calculation module includes:

[0180] a frequency bandwidth sub-module configured to analyze the seismic data volume to be measured based on Fourier transform to obtain the seismic frequency bandwidth;

[0181] an envelope sub-module configured to calculate the data volume envelope according to the seismic data volume to be measured based on Hilbert transform and the seismic frequency bandwidth;

[0182] a coefficient sub-module configured to calculate a separation coefficient based on a preset separation coefficient calculation formula according to the maximum value and the minimum value of the data volume envelope.

[0183] In one embodiment, the preset envelope calculation formula is shown in Formula (1):

[0184]

[0185] In Formula (1), e is the data volume envelope, D shot(H) 2 (x, y, t) is the Hilbert data volume, D shot (x, y, t) is the seismic data volume to be measured.

[0186] In one embodiment, the preset separation coefficient calculation formula is shown in Equation (2):

[0187]

[0188] In Equation (2), δ(x, y, t) is the separation coefficient, e max is the maximum value of the data volume envelope, e min is the minimum value of the data volume envelope.

[0189] In one embodiment, the preset mode decomposition calculation formula is shown in Equation (3):

[0190]

[0191] In Equation (3), D shot (x, y, t) is the seismic data volume to be measured, δ k (x, y, t) is the separation coefficient, IMF k (x, y, t) is the data volume obtained after decomposition, i.e., the decomposed data volume, and k is the number of decompositions.

[0192] In one embodiment, the preset signal extraction calculation formula is shown in Equation (4):

[0193] r 1 (x, y, t) = D shot (x, y, t) - δ 1 (x, y, t) * IMF 1 (x, y, t) (4)

[0194] In Equation (4), r 1 (x, y, t) is the first signal, D shot (x, y, t) is the seismic data volume to be measured, δ 1 (x, y, t) is the separation coefficient, IMF 1 (x, y, t) is the decomposed data volume.

[0195] In one embodiment, the main signal component is shown in Equation (5):

[0196]

[0197] In Equation (5), D main (x, y, t) is the main signal component, r k (x, y, t) is the first signal or the second signal. When k = 1, r k (x, y, t) is the first signal. When k > 1, r k (x, y, t) is the second signal.

[0198] In one embodiment, the secondary signal component is shown in Formula (6):

[0199]

[0200] In Formula (6), D res (x, y, t) is the secondary signal component, and r k (x, y, t) is the second signal, where k > 1.

[0201] In one embodiment, the calculation formula for the preset scattered wave data volume is shown in Formula (7):

[0202] D diff (x, y, t) = 0.5 * (D shot (x, y, t) - D main (x, y, t)) + 0.5 * D res (x, y, t) (7)

[0203] In Formula (7), D diff (x, y, t) is the scattered wave data volume, D shot (x, y, t) is the seismic data volume to be measured, D main (x, y, t) is the main signal component, and D res (x, y, t) is the secondary signal component.

[0204] For the specific limitations on the device for extracting scattered waves, reference can be made to the limitations on the method for extracting scattered waves in the above text, which will not be elaborated here. Each unit in the above device for extracting scattered waves can be implemented in whole or in part through software, hardware, and their combinations. The above units can be embedded in the processor of the computer device in hardware form or be independent of it, or can be stored in the memory of the computer device in software form, so that the processor can call and execute the operations corresponding to the above units.

[0205] Embodiment Five

[0206] In this embodiment, a computer device is provided. Its internal structure diagram can be as Figure 3As shown in the figure. The computer device includes a processor, a memory, a network interface, a display screen, and an input device connected via a system bus. Among them, the processor of the computer device is used to provide computing and control capabilities. The memory of the computer device includes a non-volatile storage medium and an internal memory. The non-volatile storage medium stores an operating system and a computer program, and a database is deployed on the non-volatile storage medium. The database is used to store a preset modal decomposition calculation formula. The internal memory provides an environment for the operation of the operating system and the computer program in the non-volatile storage medium. The network interface of the computer device is used to communicate with other computer devices on which application software is deployed. When the computer program is executed by the processor, it realizes a method for extracting scattered waves. The display screen of the computer device can be a liquid crystal display screen or an electronic ink display screen. The input device of the computer device can be a touch layer covering the display screen, or a button, a trackball, or a touchpad provided on the housing of the computer device, or an external keyboard, touchpad, or mouse, etc.

[0207] Those skilled in the art can understand that Figure 3 the structure shown in the figure is only a block diagram of some structures related to the solution of this application, and does not constitute a limitation on the computer device to which the solution of this application is applied. The specific computer device may include more or fewer components than those shown in the figure, or combine some components, or have different component arrangements.

[0208] In one embodiment, a computer device is provided, including a memory and a processor. The memory stores a computer program. When the processor executes the computer program, the following steps are implemented:

[0209] Step 110, obtaining a to-be-detected seismic data volume;

[0210] Step 120, calculating a separation coefficient based on a preset separation coefficient calculation formula according to the to-be-detected seismic data volume;

[0211] Step 130, calculating a decomposed data volume based on a preset modal decomposition calculation formula according to the to-be-detected seismic data volume and the separation coefficient;

[0212] Step 140, extracting a first signal based on a preset signal extraction calculation formula according to the to-be-detected seismic data volume, the separation coefficient, and the decomposed data volume;

[0213] Step 150, repeatedly executing steps 120 to 140 multiple times to sequentially extract a second signal;

[0214] Step 160, calculating a scattered wave data volume based on a preset scattered wave data volume calculation formula according to the to-be-detected seismic data volume, the first signal, and the second signal.

[0215] In one embodiment, when the processor executes the computer program, the following steps are further implemented:

[0216] Obtain the original seismic data volume, separate the original seismic data volume according to the offset, and obtain the seismic data volume to be measured.

[0217] In one embodiment, when the processor executes the computer program, the following steps are further implemented:

[0218] Synthesize the scattered wave field according to the scattered wave data volumes corresponding to the respective offsets.

[0219] In one embodiment, when the processor executes the computer program, the following steps are further implemented:

[0220] Step 161, obtain a preset serial number threshold;

[0221] Step 162, when the signal order is less than the preset serial number threshold, superimpose the first signal and the second signals corresponding to the signal order to obtain a main signal component, where the signal order is the serial number set for the first signal and each of the second signals according to the order of signal output;

[0222] Step 163, when the signal order is greater than or equal to the preset serial number threshold, superimpose the second signals corresponding to the signal order to obtain a secondary signal component;

[0223] Step 164, based on the preset scattered wave data volume calculation formula, calculate the scattered wave data volume according to the seismic data volume to be measured, the main signal component, and the secondary signal component.

[0224] In one embodiment, when the processor executes the computer program, the following steps are further implemented:

[0225] Step 121, analyze the seismic data volume to be measured based on Fourier transform to obtain the seismic frequency band width;

[0226] Step 122, based on Hilbert transform and the seismic frequency band width, calculate the data volume envelope according to the seismic data volume to be measured;

[0227] Step 123, based on the preset separation coefficient calculation formula, calculate the separation coefficient according to the maximum and minimum values of the data volume envelope.

[0228] Embodiment Six

[0229] In this embodiment, a computer-readable storage medium is provided, on which a computer program is stored. When the computer program is executed by a processor, the following steps are implemented:

[0230] Step 110, obtain the seismic data volume to be measured;

[0231] Step 120: Calculate the separation coefficient according to the seismic data volume to be measured based on a preset separation coefficient calculation formula.

[0232] Step 130: Calculate the decomposed data volume according to the seismic data volume to be measured and the separation coefficient based on a preset modal decomposition calculation formula.

[0233] Step 140: Extract the first signal according to the seismic data volume to be measured, the separation coefficient, and the decomposed data volume based on a preset signal extraction calculation formula.

[0234] Step 150: Repeatedly execute Steps 120 to 140 multiple times to sequentially extract the second signal.

[0235] Step 160: Calculate the scattered wave data volume according to the seismic data volume to be measured, the first signal, and the second signal based on a preset scattered wave data volume calculation formula.

[0236] In one embodiment, when the computer program is executed by a processor, the following steps are further implemented:

[0237] Obtain the original seismic data volume, and separate the original seismic data volume according to the offset to obtain the seismic data volume to be measured.

[0238] In one embodiment, when the computer program is executed by a processor, the following steps are further implemented:

[0239] Synthesize the scattered wave field according to the scattered wave data volume corresponding to each offset.

[0240] In one embodiment, when the computer program is executed by a processor, the following steps are further implemented:

[0241] Step 161: Obtain a preset serial number threshold.

[0242] Step 162: When the signal order is less than the preset serial number threshold, superimpose the first signal and the second signal corresponding to the signal order to obtain the main signal component, where the signal order is the serial number set for the first signal and each second signal according to the order of signal output.

[0243] Step 163: When the signal order is greater than or equal to the preset serial number threshold, superimpose the second signal corresponding to the signal order to obtain the secondary signal component.

[0244] Step 164: Calculate the scattered wave data volume according to the seismic data volume to be measured, the main signal component, and the secondary signal component based on the preset scattered wave data volume calculation formula.

[0245] In one embodiment, when the computer program is executed by a processor, the following steps are further implemented:

[0246] Step 121: Analyze the seismic data volume to be measured based on Fourier transform to obtain the seismic frequency band width;

[0247] Step 122: Calculate the data volume envelope according to the seismic data volume to be measured based on Hilbert transform and the seismic frequency band width;

[0248] Step 123: Calculate the separation coefficient according to the maximum value and the minimum value of the data volume envelope based on a preset separation coefficient calculation formula.

[0249] Those of ordinary skill in the art can understand that all or part of the processes in the methods of the above embodiments can be completed by instructing relevant hardware through a computer program. The computer program can be stored in a non-volatile computer-readable storage medium. When the computer program is executed, it can include the processes of the embodiments of the above methods. Among them, any reference to a memory, storage, database, or other medium used in the embodiments provided in the present application can include non-volatile and / or volatile memories. Non-volatile memories can include read-only memory (ROM), programmable ROM (PROM), electrically programmable ROM (EPROM), electrically erasable programmable ROM (EEPROM), or flash memory. Volatile memories can include random access memory (RAM) or external cache memory. By way of illustration and not limitation, RAM is available in many forms, such as static RAM (SRAM), dynamic RAM (DRAM), synchronous DRAM (SDRAM), double data rate SDRAM (DDR SDRAM), enhanced SDRAM (ESDRAM), synchronous link DRAM (SLDRAM), Rambus direct RAM (RDRAM), direct memory bus dynamic RAM (DRDRAM), and Rambus dynamic RAM (RDRAM), etc.

[0250] The technical features of the above embodiments can be combined arbitrarily. For the sake of brevity of description, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, it should be considered as the scope recorded in this specification.

[0251] The above-described embodiments merely represent several implementation manners of the present application. The description thereof is relatively specific and detailed, but it should not be construed as a limitation on the scope of the invention patent. It should be noted that for those of ordinary skill in the art, without departing from the concept of the present application, several modifications and improvements can still be made, and these all fall within the protection scope of the present application. Therefore, the protection scope of the patent of the present application shall be subject to the appended claims.

Claims

1. A method for extracting scattered waves, characterized in that, comprising: Step a, obtaining a seismic data volume to be measured; Step b, calculating a separation coefficient based on a preset separation coefficient calculation formula according to the seismic data volume to be measured; Step c, calculating a decomposed data volume based on a preset mode decomposition calculation formula according to the seismic data volume to be measured and the separation coefficient; Step d, extracting a first signal based on a preset signal extraction calculation formula according to the seismic data volume to be measured, the separation coefficient, and the decomposed data volume; Step e, repeatedly executing Step b to Step d multiple times to sequentially extract second signals; Step f, calculating a scattered wave data volume based on a preset scattered wave data volume calculation formula according to the seismic data volume to be measured, the first signal, and the second signal.

2. The method for extracting scattered waves according to claim 1, characterized in that, Step a, the step of obtaining a seismic data volume to be measured includes: Obtaining an original seismic data volume, and separating the original seismic data volume according to offset to obtain the seismic data volume to be measured.

3. The method for extracting scattered waves according to claim 2, characterized in that, After Step f, calculating a scattered wave data volume based on a preset scattered wave data volume calculation formula according to the seismic data volume to be measured, the first signal, and the second signal, includes: Synthesizing a scattered wave field according to the scattered wave data volume corresponding to each offset.

4. The method for extracting scattered waves according to claim 1, characterized in that, Step f, the step of calculating a scattered wave data volume based on a preset scattered wave data volume calculation formula according to the seismic data volume to be measured, the first signal, and the second signal, includes: Step f1, obtaining a preset sequence number threshold; Step f2, when the signal sequence is less than the preset sequence number threshold, superimposing the first signal and the second signal corresponding to the signal sequence to obtain a main signal component, where the signal sequence is a sequence number set for the first signal and each second signal according to the order of signal output; Step f3, when the signal sequence is greater than or equal to the preset sequence number threshold, superimposing the second signal corresponding to the signal sequence to obtain a secondary signal component; Step f4, calculating the scattered wave data volume based on the preset scattered wave data volume calculation formula according to the seismic data volume to be measured, the main signal component, and the secondary signal component.

5. The method for extracting scattered waves according to claim 1, characterized in that, Step b, the step of calculating a separation coefficient based on a preset separation coefficient calculation formula according to the seismic data volume to be measured, includes: Step b1, analyzing the seismic data volume to be measured based on Fourier transform to obtain a seismic frequency band width; Step b2, calculating a data volume envelope based on Hilbert transform and the seismic frequency band width according to the seismic data volume to be measured; Step b3, calculating a separation coefficient based on a preset separation coefficient calculation formula according to the maximum value and the minimum value of the data volume envelope.

6. A device for extracting scattered waves, characterized in that, comprising: A to-be-measured data acquisition module: used to execute Step a to obtain a seismic data volume to be measured; Separation coefficient calculation module: used to execute step b, calculate the separation coefficient based on a preset separation coefficient calculation formula according to the seismic data volume to be measured; Decomposed data calculation module: used to execute step c, calculate the decomposed data volume based on a preset modal decomposition calculation formula according to the seismic data volume to be measured and the separation coefficient; First signal extraction module: used to execute step d, extract the first signal based on a preset signal extraction calculation formula according to the seismic data volume to be measured, the separation coefficient, and the decomposed data volume; Second signal extraction module: used to execute step e, repeatedly execute steps b to d multiple times to sequentially extract the second signal; Scattering data calculation module: used to execute step f, calculate the scattered wave data volume based on a preset scattered wave data volume calculation formula according to the seismic data volume to be measured, the first signal, and the second signal.

7. The scattered wave extraction device according to claim 6, wherein, the device further includes: To-be-measured data acquisition module: used to acquire the original seismic data volume, separate the original seismic data volume according to the offset to obtain the seismic data volume to be measured.

8. The scattered wave extraction device according to claim 6, wherein, the device further includes: Wavelength synthesis module: used to synthesize the scattered wave field according to the scattered wave data volumes corresponding to each offset.

9. A computer device, including a memory and a processor, the memory stores a computer program, wherein, when the processor executes the computer program, the steps of the method according to any one of claims 1 to 5 are implemented.

10. A computer-readable storage medium, on which a computer program is stored, wherein, when the computer program is executed by the processor, the steps of the method according to any one of claims 1 to 5 are implemented.

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