Direct wave identification and removal method and device based on local fast matching

Abstract

This application proposes a method and apparatus for identifying and removing direct waves based on local fast matching. The proposed technical solution uses seismic wavelets estimated from close-offset seismic records. These wavelets are then used for waveform matching within a dynamic time window to accurately identify direct waves, which are then subtracted from the seismic records. This addresses the issue of inaccurate direct wave removal or loss of effective signal in conventional methods.

Description

Technical Field

[0001] The present invention relates to the field of seismic data processing and interpretation in oil and gas exploration and development, and more particularly to a method and device for identifying and removing direct waves based on local fast matching. Background Art

[0002] Direct wave removal in seismic data is a basic step in seismic data processing. The effect of direct wave removal has a great impact on subsequent seismic data processing and interpretation.

[0003] Conventional direct wave removal methods often present numerous practical challenges. One common approach involves manually removing direct waves from seismic shot gather data within a specific time window. This removes all signals within the window and fails to address the mixing of direct waves with other significant waves, leading to loss of significant signal. Another approach involves simulating direct waves through forward modeling and then removing them by subtraction. While forward modeling can generate direct waves, it requires a high level of accuracy in the near-surface velocity model. Furthermore, forward modeling also simulates waveform information such as return waves, and subtracting the simulated seismic records from the actual seismic records also results in a loss of significant wave information.

[0004] With the deepening of oil and gas exploration, the exploration targets are becoming more complex, which places higher demands on the fidelity of seismic data processing. Therefore, accurate and reliable direct wave identification and removal methods are needed. Summary of the Invention

[0005] In view of this, the present application proposes a method for identifying and removing direct waves based on local fast matching, and the present application also proposes corresponding devices, electronic devices, and computer-readable storage media.

[0006] According to one aspect of the present application, a method for identifying and removing direct waves based on local fast matching is proposed, the method comprising:

[0007] Select the near-offset seismic data u(x, y, z; t; x r ), the specified time window is determined according to the direct wave range and based on the near-offset seismic data u(x, y, z; t; x r ) Extract the seismic wavelet w(t) according to the time reverse extension;

[0008] The extracted seismic wavelet w(t) is time-shifted to construct the seismic wavelet library w j (t), j = 1, 2, ..., J, j represents the wavelet number, and J refers to the total number of wavelets;

[0009] Calculate the d of each seismic signal in the full offset seismic record i(t), and determine the seismic signal d according to the instantaneous envelope i (t) the corresponding matching wavelet time shift range, i=1, 2, ..., I, where i represents the channel number of the seismic signal and I refers to the total number of channels of the seismic signal in the full-offset seismic record;

[0010] For each seismic signal d i (t), the earthquake signal d i (t) Match the wavelet in the corresponding matching wavelet time shift range to identify the seismic signal d i The direct wave m in (t) i (t), i=1, 2, ..., I;

[0011] Subtract the direct wave m from the full-offset seismic record i (t), i = 1, 2, ..., I, to remove the direct wave in the seismic record.

[0012] In a possible implementation manner, the time-reverse extension specifically includes:

[0013] From t = T max From the moment t = 0, the wave field is extrapolated in reverse time according to the following wave equation in the direction of decreasing time until the waveform at the source point is obtained, which is the seismic wavelet w(t):

[0014]

[0015] Among them, T max represents the maximum moment of the specified time window, Δ refers to the Laplace operator, x, y, and z represent the spatial coordinate positions respectively, and x r represents the position of the detection point, and the wave field propagation boundary condition is set to p(x, y, z = 0; t; x r )=u(x,y,z=0;t;x r ).

[0016] In a possible implementation, the seismic signal d is determined based on the instantaneous envelope. i (t) The corresponding matching wavelet time shift range, i=1, 2, ..., I specifically includes:

[0017] Determining the time corresponding to the peak of the instantaneous envelope as the center of the matching wavelet time shift range;

[0018] A preset time width range including the center is determined as the matching wavelet time shift range.

[0019] In a possible implementation, the identification of the seismic signal d i The direct wave m in (t) i(t), i=1, 2, ..., I specifically includes:

[0020] The signal m is obtained based on the following formula ij (t):

[0021] m ij (t)= <d i (t), w j (t)>w j (t)

[0022] Where j = [J iL ,...,J iH ], is the earthquake signal d i (t) The wavelet number of each wavelet within the corresponding matching wavelet time shift range, <d i (t), w j (t)> indicates the calculation of d i (t) and w j the inner product of (t);

[0023] Determine m ij (t), j = J iL ,...,J iH The largest amplitude m ij (t) is the direct wave m i (t).

[0024] According to another aspect of the present application, an electronic device is further provided, comprising:

[0025] a memory storing executable instructions;

[0026] A processor runs the executable instructions in the memory to implement the method described above.

[0027] According to another aspect of the present application, a computer-readable storage medium is provided, wherein the computer-readable storage medium stores a computer program, and when the computer program is executed by a processor, the method described above is implemented.

[0028] According to another aspect of the present application, a device for identifying and removing direct waves based on local fast matching is also proposed, the device comprising:

[0029] The wavelet extraction unit is used to select the near-offset seismic data u(x, y, z; t; x r ), the specified time window is determined according to the direct wave range and based on the near-offset seismic data u(x, y, z; t; x r ) Extract the seismic wavelet w(t) according to the time reverse extension;

[0030] The wavelet library construction unit is used to time-shift the extracted seismic wavelet w(t) and construct the seismic wavelet library w j (t), j = 1, 2, ..., J, j represents the wavelet number, and J refers to the total number of wavelets;

[0031] The instantaneous envelope calculation unit is used to obtain the d of each seismic signal in the full offset seismic record. i (t), and determine the seismic signal d according to the instantaneous envelope i (t) the corresponding matching wavelet time shift range, i=1, 2, ..., I, where i represents the channel number of the seismic signal and I refers to the total number of channels of the seismic signal in the full-offset seismic record;

[0032] Direct wave identification unit, used for each seismic signal d i (t), the earthquake signal d i (t) Match the wavelet in the corresponding matching wavelet time shift range to identify the seismic signal d i The direct wave m in (t) i (t), i=1, 2, ..., I;

[0033] A direct wave removal unit is used to subtract the direct wave m from the full offset seismic record. i (t), i = 1, 2, ..., I, to remove the direct wave in the seismic record.

[0034] In a possible implementation, the wavelet extraction unit further includes a time-inverse extension subunit, and the time-inverse extension subunit is specifically configured to:

[0035] From t = T max From the moment t = 0, the wave field is extrapolated in reverse time according to the following wave equation in the direction of decreasing time until the waveform at the source point is obtained, which is the seismic wavelet w(t):

[0036]

[0037] Among them, T max represents the maximum moment of the specified time window, Δ refers to the Laplace operator, x, y, and z represent the spatial coordinate positions respectively, and x r represents the position of the detection point, and the wave field propagation boundary condition is set to p(x, y, z = 0; t; x r )=u(x,y,z=0;t;x r ).

[0038] In a possible implementation, the instantaneous envelope calculation unit is specifically configured to:

[0039] Determining the time corresponding to the peak of the instantaneous envelope as the center of the matching wavelet time shift range;

[0040] A preset time width range including the center is determined as the matching wavelet time shift range.

[0041] In a possible implementation manner, it is characterized in that: the direct wave identification unit is specifically used to:

[0042] For each seismic signal d i (t), the signal m is obtained based on the following formula ij (t):

[0043] m ij (t)= <d i (t), w j (t)>w j (t)

[0044] Where j = J iL ,...,J iH , is the earthquake signal d i (t) The wavelet number of each wavelet within the corresponding matching wavelet time shift range, <d i (t), w j (t)> indicates the calculation of d i (t) and w j the inner product of (t);

[0045] Determine m ij (t), j = J iL ,...,J iH The largest amplitude m ij (t) is the direct wave m i (t).

[0046] The technical solution proposed in this application is to estimate seismic wavelets based on near-offset seismic records, use seismic wavelets to perform waveform matching within a dynamic time window, accurately identify direct waves, and then subtract and remove them from the seismic records, thereby solving the problem of inaccurate direct wave removal or loss of effective signals in conventional methods. BRIEF DESCRIPTION OF THE DRAWINGS

[0047] The above and other objects, features and advantages of the present application will become more apparent through a more detailed description of exemplary embodiments of the present application in conjunction with the accompanying drawings, wherein the same reference numerals generally represent the same components in the exemplary embodiments of the present application.

[0048] Figure 1 A schematic flow chart of a method for identifying and removing direct waves based on local fast matching according to an embodiment of the present application is shown.

[0049] Figure 2The figure shows a structural block diagram of a direct wave identification and removal device based on local fast matching according to an embodiment of the present application.

[0050] Figure 3 A schematic diagram showing a synthetic seismic record.

[0051] Figure 4 According to the present invention, Figure 3 Schematic diagram of the direct arrival waves identified in the earthquake record shown.

[0052] Figure 5 Showing that according to the present invention Figure 3 Schematic diagram of seismic records after direct wave removal. DETAILED DESCRIPTION

[0053] The preferred embodiments of the present application will be described in more detail below with reference to the accompanying drawings. Although the preferred embodiments of the present application are shown in the accompanying drawings, it should be understood that the present application can be implemented in various forms and should not be limited by the embodiments described herein. Instead, these embodiments are provided to make the present application more thorough and complete, and to fully convey the scope of the present application to those skilled in the art.

[0054] According to one aspect of the present application, a method for identifying and removing direct waves based on local fast matching is provided.

[0055] See Figure 1 . Figure 1 The flowchart of the method for identifying and removing direct waves based on local fast matching according to an embodiment of the present application is shown. As shown in the figure, the method includes steps 1 to 6.

[0056] Step 1: Select the near-offset seismic data u(x, y, z; t; x r ), the specified time window is determined according to the direct wave range and based on the near-offset seismic data u(x, y, z; t; x r ) Extract the seismic wavelet w(t) according to the time reverse extension.

[0057] After research, the inventors found that far-offset data usually contains a lot of interference information such as refracted waves. Therefore, extracting seismic wavelets from near-offset data can further improve the accuracy of identifying direct waves.

[0058] Those skilled in the art can determine the designated window based on experience. For high-quality earthquake records where direct waves are easily visible, the position and width of the designated window can be determined relatively directly. For low-quality earthquake records where direct waves are difficult to visually identify, the designated window can be set based on past experience and understanding of the local earthquake data.

[0059] In some embodiments, reverse time extension can be performed according to the following method to obtain the seismic wavelet w(t). max From the moment t = 0, the wave field is extrapolated in reverse time according to the following wave equation in the direction of decreasing time until the waveform at the source point is obtained, which is the seismic wavelet w(t):

[0060]

[0061] Among them, T max represents the maximum moment of the specified time window, Δ refers to the Laplace operator, x, y, and z represent the spatial coordinate positions respectively, and x r represents the position of the detection point, and the wave field propagation boundary condition is set to p(x, y, z = 0; t; x r )=u(x,y,z=0;t;x r ).

[0062] Step 2: Time-shift the extracted seismic wavelet w(t) to construct the seismic wavelet library w j (t), j = 1, 2, ..., J, j represents the wavelet number, and J refers to the total number of wavelets.

[0063] Step 3: Calculate the d of each seismic signal in the full offset seismic record. i (t), and determine the seismic signal d according to the instantaneous envelope i (t) The corresponding matching wavelet time shift range, i=1, 2, ..., I, i represents the channel number of the seismic signal, and I refers to the total number of seismic signal channels in the full-offset seismic record.

[0064] In some embodiments, the matching wavelet time shift range can be determined by the following method: First, the time corresponding to the peak of the forward envelope is determined as the center of the matching wavelet time shift range, i.e., the time window is located; then, a preset time width range including the center is determined as the matching wavelet time shift range, i.e., the width of the time window is determined.

[0065] The time shift range of the matching wavelet is obtained through step 3, which greatly reduces the range of the wavelet that can be used for matching when the seismic signal and the wavelet are subsequently matched, thereby significantly improving the calculation efficiency.

[0066] Step 4: For each seismic signal d i (t), the earthquake signal d i (t) Match the wavelet in the corresponding matching wavelet time shift range to identify the seismic signal d i The direct wave m in (t) i (t), i=1, 2, ..., I.

[0067] In some embodiments, seismic signals d can be identified by the following method: i The direct wave m in (t) i (t), i=1, 2, ..., .

[0068] The signal m can be obtained based on the following formula ij (t):

[0069] m ij (t)= <d i (t), w j (t)>w j (t)

[0070] Where j = [J iL ,...,J iH ], is the earthquake signal d i (t) The wavelet number of each wavelet within the corresponding matching wavelet time shift range, <d i (t), w j (t)> indicates the calculation of d i (t) and w j the inner product of (t);

[0071] Determine m ij (t), j = J iL ,...,J iH The largest amplitude m ij (t) is the direct wave m i (t).

[0072] Due to the direct wave i (t) is obtained by wavelet matching, so it does not contain signals such as refracted waves. i (t) is the full-offset seismic record, and the corresponding direct wave m i (t) is the full-offset direct-arrival seismic wave, or the full-data-volume direct-arrival seismic wave, i=1,2,...,I.

[0073] Step 5: Subtract the direct wave m from the full offset seismic record. i (t), i = 1, 2, ..., I, to remove the direct wave in the seismic record.

[0074] In the above embodiment, the direct wave of the near-offset seismic record is subjected to the wave field continuation method to obtain the seismic wavelet, and the wave field matching is performed based on the seismic wavelet to obtain the seismic direct wave of the entire data volume. The wave field matching is performed based on the seismic wavelet characteristics, which conforms to the waveform characteristics of the seismic direct wave. The identified direct wave is more accurate, so other effective signal energy will not be lost when the direct wave is removed, providing more accurate seismic data for subsequent seismic data processing and interpretation.

[0075] According to another aspect of the present application, a device for identifying and removing direct waves based on local fast matching is also provided. Figure 2 . Figure 2 The figure shows a structural block diagram of a direct wave identification and removal device based on local fast matching according to an embodiment of the present application.

[0076] like Figure 2 As shown, the device includes a wavelet extraction unit 201, a wavelet library construction unit 202, an instantaneous envelope calculation unit 203, a direct wave identification unit 204 and a direct wave removal unit 205.

[0077] The wavelet extraction unit 201 is used to select the near-offset seismic data u(x, y, z; t; x r ), the specified time window is determined according to the direct wave range and based on the near-offset seismic data u(x, y, z; t; x r ) Extract the seismic wavelet w(t) according to the time reverse extension;

[0078] The wavelet library construction unit 202 is used to time-shift the extracted seismic wavelet w(t) to construct the seismic wavelet library w j (t), j = 1, 2, ..., J, j represents the wavelet number, and J refers to the total number of wavelets;

[0079] The instantaneous envelope calculation unit 203 is used to obtain the d of each seismic signal in the full offset seismic record. i (t), and determine the seismic signal d according to the instantaneous envelope i (t) the corresponding matching wavelet time shift range, i=1, 2, ..., I, where i represents the channel number of the seismic signal and I refers to the total number of channels of the seismic signal in the full-offset seismic record;

[0080] The direct wave identification unit 204 is used to identify each seismic signal d i (t), the earthquake signal d i (t) Match the wavelet in the corresponding matching wavelet time shift range to identify the seismic signal d i The direct wave m in (t) i (t), i=1,2,...,I;

[0081] The direct wave removal unit 205 is used to subtract the direct wave m from the full offset seismic record. i (t), i = 1, 2, ..., I, to remove the direct wave in the seismic record.

[0082] In some embodiments, the wavelet extraction unit 201 may further include a time-inverse extension subunit, which may be used to:

[0083] From t = T max From the moment t = 0, the wave field is extrapolated in reverse time according to the following wave equation in the direction of decreasing time until the waveform at the source point is obtained, which is the seismic wavelet w(t):

[0084]

[0085] Among them, T max represents the maximum moment of the specified time window, Δ refers to the Laplace operator, x, y, and z represent the spatial coordinate positions respectively, and x r represents the position of the detection point, and the wave field propagation boundary condition is set to p(x, y, z = 0; t; x r )=u(x,y,z=0;t;x r ).

[0086] In some implementations, the instantaneous envelope calculation unit 203 may be specifically configured to:

[0087] Determining the time corresponding to the peak of the instantaneous envelope as the center of the matching wavelet time shift range;

[0088] A preset time width range including the center is determined as the matching wavelet time shift range.

[0089] In some implementations, the direct wave identification unit 204 may be specifically configured to:

[0090] For each seismic signal d i (t), the signal m is obtained based on the following formula ij (t):

[0091] m ij (t)= <d i (t), w j (t)>w j (t)

[0092] Where j = J iL ,...,J iH , is the earthquake signal d i (t) The wavelet number of each wavelet within the corresponding matching wavelet time shift range, <d i (t), w j (t)> indicates the calculation of d i (t) and w j the inner product of (t);

[0093] Determine m ij (t), j = J iL ,...,J iH The largest amplitude m ij (t) is the direct wave m i(t).

[0094] For other detailed descriptions of this embodiment, please refer to the corresponding descriptions in the aforementioned embodiments, which will not be repeated here.

[0095] According to another aspect of the present application, an electronic device is provided. The electronic device includes:

[0096] a memory storing executable instructions;

[0097] A processor runs the executable instructions in the memory to implement the direct wave identification and removal method based on local fast matching as described above.

[0098] Specifically, the memory may include one or more computer program products, which may include various forms of computer-readable storage media, such as volatile memory and / or non-volatile memory. The volatile memory may include, for example, random access memory (RAM) and / or cache memory. The non-volatile memory may include, for example, read-only memory (ROM), a hard disk, a flash memory, etc.

[0099] The processor may be a central processing unit (CPU) or other forms of processing units having data processing capabilities and / or instruction execution capabilities, and may control other components in the electronic device to perform desired functions. In one embodiment of the present application, the processor is used to run the computer-readable instructions stored in the memory.

[0100] For detailed description of this embodiment, please refer to the corresponding description in the aforementioned embodiments, which will not be repeated here.

[0101] According to another aspect of the present application, a computer-readable storage medium is provided, which stores a computer program. When the computer program is executed by a processor, it implements the direct wave identification and removal method based on local fast matching as described above.

[0102] According to the computer-readable storage medium of the embodiment of the present application, non-transitory computer-readable instructions are stored thereon. When the non-transitory computer-readable instructions are executed by a processor, all or part of the steps of the aforementioned methods of the embodiments of the present application are executed.

[0103] The above-mentioned computer-readable storage media include, but are not limited to: optical storage media (e.g., CD-ROM and DVD), magneto-optical storage media (e.g., MO), magnetic storage media (e.g., magnetic tape or mobile hard disk), media with built-in rewritable non-volatile memory (e.g., memory card) and media with built-in ROM (e.g., ROM box).

[0104] Those skilled in the art should understand that in order to solve the technical problem of how to obtain a good user experience, this embodiment may also include well-known structures such as a communication bus and an interface, and these well-known structures should also be included in the scope of protection of this application.

[0105] For detailed description of this embodiment, please refer to the corresponding description in the aforementioned embodiments, which will not be repeated here.

[0106] Figure 3 A schematic diagram of a synthetic seismic record is shown. According to the present application, the near-offset seismic data containing direct waves in the synthetic seismic record are selected for seismic wavelet extraction, and the extracted seismic wavelet is matched with the full-offset seismic record to identify the direct waves in the full-offset seismic record. The identified direct waves are as follows: Figure 4 As shown. Figure 4 It can be seen that the identified direct wave is consistent with the direct wave in the original seismic record and does not contain other waveform signals. Then the original seismic record is subtracted from the identified direct wave to obtain the seismic record after removing the direct wave, as shown in Figure 5 As shown in the figure, it can be seen that after the synthetic seismic record is processed according to the present invention, the effective signal in the seismic record is completely preserved. This example fully verifies that the direct wave can be accurately identified and removed according to the present invention, proving the accuracy and reliability of the technical solution disclosed in the present invention.

[0107] The embodiments of the present application have been described above. The above description is illustrative and not exhaustive, and is not limited to the disclosed embodiments. Many modifications and variations will be apparent to those skilled in the art without departing from the scope and spirit of the described embodiments. The terminology used herein is selected to best explain the principles of the embodiments, practical applications, or technical improvements to existing technologies, or to enable other persons skilled in the art to understand the embodiments disclosed herein.

Claims

1. A method for identifying and removing direct waves based on local fast matching, characterized in that: The method comprises: Select the near-offset seismic data u(x,y,z; t; x r ), the specified time window is determined according to the direct wave range and based on the near-offset seismic data u(x,y,z; t; x r ) Extract the seismic wavelet w(t) according to the time reverse extension; The extracted seismic wavelet w(t) is time-shifted to construct the seismic wavelet library w j (t), j = 1, 2, ..., J, j represents the wavelet number, and J refers to the total number of wavelets; Calculate the d of each seismic signal in the full offset seismic record i (t), and determine the seismic signal d according to the instantaneous envelope i (t) the corresponding matching wavelet time shift range, i=1, 2, ..., I, where i represents the channel number of the seismic signal and I refers to the total number of channels of the seismic signal in the full-offset seismic record; For each seismic signal d i (t), the earthquake signal d i (t) Match the wavelet in the corresponding matching wavelet time shift range to identify the seismic signal d i The direct wave m in (t) i (t), i=1,2,…,I; Subtract the direct wave m from the full-offset seismic record i (t), i = 1, 2, ..., I, to remove the direct wave in the seismic record; Wherein, the identified earthquake signal d i The direct wave m in (t) i (t), i=1,2,…,I, specifically including: The signal m is obtained based on the following formula ij (t): m ij (t)=<d i (t),w j (t)>w j (t) Where j = J iL ,…,J iH , is the earthquake signal d i (t) The wavelet number of each wavelet within the corresponding matching wavelet time shift range, <d i (t),w j (t)> indicates the calculation of d i (t) and w j the inner product of (t); Determine m ij m with the largest amplitude in (t) ij (t) is the direct wave m i (t), j = J iL ,…,J iH .

2. The method according to claim 1, characterized in that The time-reversal extension specifically includes: From t = T max From the moment t = 0, the wave field is extrapolated in reverse time according to the following wave equation in the direction of decreasing time until the waveform at the source point is obtained, which is the seismic wavelet w(t): Among them, T max represents the maximum moment of the specified time window, Δ refers to the Laplace operator, x, y, and z represent the spatial coordinate positions respectively, and x r represents the position of the detection point, and the wave field propagation boundary condition is set to p(x, y, z = 0; t; x r )=u(x,y,z=0;t;x r ).

3. The method according to claim 1, characterized in that The seismic signal d is determined according to the instantaneous envelope. i (t) The corresponding matching wavelet time shift range, i = 1, 2, ..., I, specifically includes: Determining the time corresponding to the peak of the instantaneous envelope as the center of the matching wavelet time shift range; A preset time width range including the center is determined as the matching wavelet time shift range.

4. An electronic device, characterized in that: The electronic device comprises: a memory storing executable instructions; A processor, wherein the processor runs the executable instructions in the memory to implement the method according to any one of claims 1 to 3.

5. A computer-readable storage medium, characterized in that The computer-readable storage medium stores a computer program, and when the computer program is executed by a processor, the method according to any one of claims 1 to 3 is implemented.

6. A direct wave identification and removal device based on local fast matching, characterized in that: The device comprises: The wavelet extraction unit is used to select the near-offset seismic data u(x, y, z; t; x r ), the specified time window is determined according to the direct wave range and based on the near-offset seismic data u(x,y,z; t; x r ) Extract the seismic wavelet w(t) according to the time reverse extension; The wavelet library construction unit is used to time-shift the extracted seismic wavelet w(t) and construct the seismic wavelet library w j (t), j = 1, 2, ..., J, j represents the wavelet number, and J refers to the total number of wavelets; The instantaneous envelope calculation unit is used to obtain the d of each seismic signal in the full offset seismic record. i (t), and determine the seismic signal d according to the instantaneous envelope i (t) the corresponding matching wavelet time shift range, i=1, 2, ..., I, where i represents the channel number of the seismic signal and I refers to the total number of channels of the seismic signal in the full-offset seismic record; Direct wave identification unit, used for each seismic signal d i (t), the earthquake signal d i (t) Match the wavelet in the corresponding matching wavelet time shift range to identify the seismic signal d i The direct wave m in (t) i (t), i=1,2,…,I; A direct wave removal unit is used to subtract the direct wave m from the full offset seismic record. i (t), i = 1, 2, ..., I, to remove the direct wave in the seismic record, The direct wave identification unit is specifically used for: For each seismic signal d i (t), the signal m is obtained based on the following formula ij (t): m ij (t)=<d i (t),w j (t)>w j (t) Where j = J iL ,…,J iH , is the earthquake signal d i (t) The wavelet number of each wavelet within the corresponding matching wavelet time shift range, <d i (t),w j (t)> indicates the calculation of d i (t) and w j the inner product of (t); Determine m ij m with the largest amplitude in (t) ij (t) is the direct wave m i (t), j = J iL ,…,J iH .

7. The device according to claim 6, characterized in that The wavelet extraction unit further includes an inverse time-delay subunit, which is specifically configured to: From t = T max From the moment t = 0, the wave field is extrapolated in reverse time according to the following wave equation in the direction of decreasing time until the waveform at the source point is obtained, which is the seismic wavelet w(t): Among them, T max represents the maximum moment of the specified time window, Δ refers to the Laplace operator, x, y, and z represent the spatial coordinate positions respectively, and x r represents the position of the detection point, and the wave field propagation boundary condition is set to p(x, y, z = 0; t; x r )=u(x,y,z=0;t;x r ).

8. The device according to claim 6, characterized in that The instantaneous envelope calculation unit is specifically used for: Determining the time corresponding to the peak of the instantaneous envelope as the center of the matching wavelet time shift range; A preset time width range including the center is determined as the matching wavelet time shift range.

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