A borehole pattern reflected wave identification method, suppression method and storage medium

Abstract

The present application relates to the field of petroleum and natural gas geophysical exploration technology, and particularly relates to a wellbore mode reflected wave identification method, a suppression method and a storage medium. The identification method comprises the following steps: drawing an original equal-source interval wave variable density map under a far monopole working mode, and observing whether there is a low-frequency reflected Stoneley wave in a wave field; performing band-pass filtering on array waveforms under the far monopole and orthogonal dipole working modes; drawing equal-source interval wave variable density maps after band-pass filtering under the far monopole and orthogonal dipole working modes respectively, and observing whether there is an upgoing or downgoing reflected wave in the wave field; calculating a slope and apparent velocity of the upgoing or downgoing reflected wave in the equal-source interval wave variable density map; and judging whether the upgoing or downgoing reflected wave is a wellbore mode reflected wave interference wave in a sound wave far detection wave field. The present application can highlight effective reflected waves from a wellbore anomaly body, suppress large-amplitude artifacts in a far detection imaging map, and improve an imaging signal-to-noise ratio.

Description

Technical Field

[0001] This invention relates to the field of geophysical exploration technology for oil and gas, specifically to a method for identifying, suppressing, and storing wellbore mode reflected waves. Background Technology

[0002] Conventional logging instruments are limited by their finite detection depth, making it difficult to meet the needs of the logging field. In contrast, acoustic long-range logging technology has a greater radial detection depth, capable of detecting formation interfaces, fractures, faults, caverns, and adjacent wells within tens of meters of the wellbore. Existing data processing methods for acoustic long-range logging are similar to those for seismic data processing: first, the received waveform undergoes wavefield separation to suppress borehole mode waves and highlight echo signals from anomalies near the wellbore; then, methods such as migration imaging are used to obtain a series of two-dimensional images on the well-axis imaging profiles.

[0003] When the wellbore is enlarged, or when there are formation interfaces or fractures near the wellbore, the acoustic remote sounding wavefield contains not only the direct wave of the wellbore mode but also the reflected wave of the wellbore mode. The amplitude of the reflected wave of the wellbore mode is on the same order of magnitude as that of the direct wave. Compared with the reflected wave of the wellbore mode, the echo amplitude of the effective reflected (scattered) wave from the well-side anomaly is relatively small. However, current acoustic remote sounding wavefield separation methods mainly focus on suppressing the direct wave of the wellbore mode, while neglecting to suppress the reflected wave of the wellbore mode.

[0004] If wellbore pattern reflected waves are not identified and suppressed, they will mask the effective reflected (scattered) waves outside the well, resulting in obvious artifacts in the imaging images and making it difficult to show the characteristics of the structures around the well. Summary of the Invention

[0005] To address the aforementioned technical problems in the prior art, this invention provides a method for identifying and suppressing wellbore mode reflected waves, as well as a storage medium, which identifies and suppresses wellbore mode reflected waves and highlights effective reflected waves from well-side anomalies.

[0006] To achieve the above objectives, the technical solution of the present invention is as follows:

[0007] In a first aspect, the present invention provides a method for identifying wellbore mode reflected waves, comprising:

[0008] Step 1: Draw the original equal-source-spacing waveform density diagram in the far-monopolar operating mode and observe whether there are low-frequency reflected Stoneley waves in the wave field;

[0009] Step 2: Perform bandpass filtering on the array waveforms in both monopole and quadrature dipole operating modes;

[0010] Step 3: Draw the variable density diagrams of the equal source distance waveforms after bandpass filtering in both far monopole and orthogonal dipole modes, and observe whether there are up-going or down-going reflected waves in the wave field.

[0011] Step 4: Calculate the slope of the upward or downward reflected wave in the variable density diagram of the equal source spacing waveform;

[0012] Step 5: Select one depth point, draw the single-shot waveform diagram of the up-going or down-going reflected wave, process the single-shot waveform diagram, and calculate the apparent velocity of the up-going or down-going reflected wave.

[0013] Step 6: Determine whether the upward or downward reflected wave is a wellbore mode reflected wave interference wave in the acoustic remote sensing wave field.

[0014] Furthermore, the slope in step 4 is calculated as follows:

[0015]

[0016] In the above formula, slope is the slope, the horizontal axis of the equal-source-distance waveform variable density map is time t, the vertical axis is depth z, (t1,z1) and (t2,z2) are the coordinates of any two points P1 and P2 on the reflected wave in the equal-source-distance waveform variable density map, and α is the angle between the reflected wave and the time t axis.

[0017] Furthermore, in step 5, the single-shot waveform is processed using the slow-time correlation method. The specific calculation method is as follows:

[0018]

[0019] in,

[0020]

[0021] In the above formula, ρ is the waveform correlation coefficient, v0 is the apparent velocity, τ is time, M is the waveform channel number, m is the waveform channel number, and T is the waveform correlation coefficient. w X is the time window length. m d represents the m-th waveform data, and d represents the spacing between logging instruments.

[0022] Furthermore, in step 6, the method for determining whether the uplink or downlink reflected wave is a wellbore mode reflected wave interference wave in the acoustic remote sensing wave field is as follows:

[0023] If either the uplink or downlink reflected wave simultaneously meets the following conditions, it is considered a wellbore mode reflected wave interference wave in the acoustic remote sensing wave field:

[0024] (1) The reflected wave extends in time and coincides with the top and wellbore mode wave;

[0025] (2) Low-frequency reflected Stoneley waves exist at the depth where the top of the reflected wave is located;

[0026] (3) The slope of the reflected wave in the equal source distance waveform density diagram is equal to half of the formation shear wave velocity, or the apparent velocity of the reflected wave in the single shot waveform is equal to the formation shear wave velocity.

[0027] Furthermore, the identification method for borehole mode reflected waves also includes:

[0028] Step 7: Combine conventional logging curves to analyze the causes of borehole mode reflection waves in the acoustic remote detection wave field.

[0029] Secondly, the present invention provides a computer-readable storage medium storing a computer program, which, when executed by a processor, implements the above-described method for identifying borehole pattern reflected waves.

[0030] Thirdly, the present invention provides a method for suppressing wellbore mode reflected waves, which suppresses reflected waves identified by the above-mentioned wellbore mode reflected wave identification method. The suppression method includes:

[0031] Step 1: Delay and gain recovery for the equidistant waveform;

[0032] Step 2: Perform bandpass filtering on the waveform with equal source spacing;

[0033] Step 3: Using the slope of the reflected wave in the borehole mode in the variable density diagram of the equal source spacing waveform as a reference, set the velocity range parameter and perform the first filtering on the equal source spacing waveform;

[0034] Step 4: Using the apparent velocity v0 of the borehole mode reflected wave in the single-shot waveform at a typical depth point as a reference, set the velocity range and perform a second filtering on the single-shot waveform.

[0035] Furthermore, the first filtering in step three is fk filtering.

[0036] Furthermore, the fk filter calculation method is as follows:

[0037]

[0038]

[0039] In the above formula, w1(t,z) is the equal-source-distance waveform data in the time-depth-z domain, W1(f,k) is the data transformed to the frequency-wavenumber-k domain, L(f,k) is the filter in the frequency-wavenumber-k domain, w2(t,x) is the equal-source-distance waveform data after fk filtering, and vlen is the set velocity range parameter.

[0040] Furthermore, in step four, the speed range is set, specifically as follows:

[0041] v0-vlen≤v≤v0+vlen

[0042] In the above formula, v is the set speed range, within which the single-shot waveform is filtered a second time.

[0043] Furthermore, the second filtering step in step four is median filtering.

[0044] Furthermore, the calculation method for median filtering is as follows:

[0045]

[0046] w' j (v,t)=w j (t+τ j (v))

[0047]

[0048] w' j '(v,t)=w med (v,t-τ j (v))

[0049]

[0050] In the formula, vlen is the set speed range parameter; d c d represents the source distance of the middle channel waveform. j τ is the source distance of the j-th waveform. j (v) represents the time shift between the j-th and intermediate channel waveforms, w j (t) represents the original waveform, w' j (v,t) represents the waveform after time shift with v as the velocity parameter, w med (v,t) represents the waveform after taking the median of the time-shifted waveform, w' j (v,t) represents the waveform after inverse time shifting the median waveform. The waveform data of the suppressed wellbore mode reflected wave is obtained by subtracting the time-shifted waveform from the original waveform.

[0051] Fourthly, the present invention provides a computer-readable storage medium storing a computer program, which, when executed by a processor, implements the above-described method for suppressing borehole mode reflected waves.

[0052] Compared with the prior art, the present invention has the following beneficial effects:

[0053] This invention provides a method for identifying wellbore mode reflected waves. Using a variable density map of an equal-source-spacing waveform, the presence of low-frequency reflected Stoneley waves in the wavefield is observed. Then, bandpass filtering is applied to the array waveform, and the presence of uplink or downlink reflected waves is observed. The slope and apparent velocity are calculated, and it is then determined whether the uplink or downlink reflected waves are interference waves from wellbore mode reflected waves in the acoustic remote sensing wavefield. This allows for accurate identification of wellbore mode reflected waves.

[0054] The wellbore mode reflection wave suppression method provided by the present invention performs fk filtering and median filtering on the reflected wave to obtain the waveform data of the suppressed wellbore mode reflection wave, highlighting the effective reflected wave from the well-side anomaly, suppressing large-amplitude artifacts in the far-field detection imaging map, and improving the imaging signal-to-noise ratio. Attached Figure Description

[0055] Figure 1 A flowchart of the wellbore mode reflection wave identification method provided by the present invention.

[0056] Figure 2 This is a schematic diagram for calculating the slope of the upward or downward reflected wave in a waveform with equal source spacing and variable density.

[0057] Figure 3 This is a waveform density diagram of a far-single pole with equal source spacing.

[0058] Figure 4 This is a waveform density diagram of an orthogonal dipole four-component equal source distance waveform.

[0059] Figure 5 This is a single-shot waveform diagram of a far-field monopole at a depth of 7525m, according to an embodiment of the present invention.

[0060] Figure 6 This is a time-dependent graph of the slow speed of a distant monopole at a depth of 7525m, according to an embodiment of the present invention.

[0061] Figure 7 This is a single-shot waveform diagram of the dipole XX component at a depth of 7525m in an embodiment of the present invention.

[0062] Figure 8 This is a time-dependent graph of the slowness of the dipole XX component at a depth of 7525m in an embodiment of the present invention.

[0063] Figure 9 This is a single-shot waveform diagram of a far-field monopole at a depth of 7542m, according to an embodiment of the present invention.

[0064] Figure 10 This is a time-dependent graph of the slow speed of a distant monopole at a depth of 7542m, according to an embodiment of the present invention.

[0065] Figure 11 This is a single-shot waveform diagram of the dipole XX component at a depth of 7542m in an embodiment of the present invention.

[0066] Figure 12 This is a time-dependent graph of the slowness of the dipole XX component at a depth of 7542m in an embodiment of the present invention.

[0067] Figure 13 A flowchart of the wellbore mode reflected wave suppression method provided by the present invention. Detailed Implementation

[0068] The technical solution of the present invention will be clearly described below with reference to the accompanying drawings. Obviously, the described embodiments are not all embodiments of the present invention. All other embodiments obtained by those skilled in the art without creative effort are within the protection scope of the present invention.

[0069] It should be noted that, unless otherwise specifically stated, the relative arrangement and numerical expressions of the components and steps described in these embodiments should not be construed as limiting the scope of the invention.

[0070] The following description of exemplary embodiments is merely illustrative and is not intended to limit the invention or its application or use in any way. Techniques, methods, and apparatus known to those skilled in the art may not be discussed in detail herein, but where applicable, such techniques, methods, and apparatus should be considered part of this specification.

[0071] Example 1

[0072] This embodiment provides a method for identifying wellbore mode reflected waves, such as... Figure 1 As shown, it includes:

[0073] Step 1: Draw the original equal-source-spacing waveform density diagram in the far-monopolar operating mode and observe whether there are low-frequency reflected Stoneley waves in the wave field;

[0074] Step 2: Bandpass filtering is applied to the array waveforms in the far monopole and quadrature dipole operating modes to suppress low-frequency Stoneley direct waves and reflected waves, as well as high-frequency noise in the wave field;

[0075] Step 3: Draw the equal source distance waveform density diagrams after bandpass filtering in both far monopole and orthogonal dipole modes, and observe whether there are up-going or down-going reflected waves in the wave field; preferably, observe whether there are obvious up-going or down-going reflected waves in the wave field.

[0076] Step 4: Calculate the slope of the upward or downward reflected wave in the variable density diagram of the equal source spacing waveform; such as... Figure 2 As shown, the slope is calculated as follows:

[0077]

[0078] In the above formula, slope is the slope, the horizontal axis of the equal-source-distance waveform variable density map is time t, the vertical axis is depth z, (t1,z1) and (t2,z2) are the coordinates of any two points P1 and P2 on the reflected wave in the equal-source-distance waveform variable density map, and α is the angle between the reflected wave and the time t axis.

[0079] Step 5: Select one depth point and plot the single-shot waveform of the up-going or down-going reflected wave. Process the single-shot waveform using the slow-time correlation method and calculate the apparent velocity of the up-going or down-going reflected wave. The specific calculation method is as follows:

[0080]

[0081] in,

[0082]

[0083] In the above formula, ρ is the waveform correlation coefficient, v0 is the apparent velocity, τ is time, M is the waveform channel number, m is the waveform channel number, and T is the waveform correlation coefficient. w X is the time window length. m d represents the m-th waveform data, and d represents the spacing between logging instruments.

[0084] Step 6: Determine whether the uplink or downlink reflected wave is a wellbore mode reflected wave interference wave in the acoustic remote sensing wave field. The specific method is as follows:

[0085] If either the uplink or downlink reflected wave simultaneously meets the following conditions, it is considered a wellbore mode reflected wave interference wave in the acoustic remote sensing wave field:

[0086] (1) The reflected wave has a longer time extension and overlaps with the top and wellbore mode wave;

[0087] (2) Low-frequency reflected Stoneley waves exist at the depth where the top of the reflected wave is located;

[0088] (3) The slope of the reflected wave in the equal source distance waveform density diagram is equal to half of the formation shear wave velocity, or the apparent velocity of the reflected wave in the single shot waveform is equal to the formation shear wave velocity.

[0089] In condition (3), if the slope of the reflected wave in the variable density diagram of the equal source spacing waveform is about half of the formation shear wave velocity, or the apparent velocity of the reflected wave in the single shot waveform is about the formation shear wave velocity, it can also be judged that condition (3) is satisfied.

[0090] Step 7: Combine conventional logging curves to analyze the causes of borehole mode reflection waves in the acoustic remote detection wave field.

[0091] (1) If the borehole diameter curve at the depth where the top of the reflected wave is located changes abnormally, it may be a borehole mode reflected wave caused by borehole enlargement.

[0092] (2) If there is a significant difference between the natural gamma curves at the upper and lower depths of the reflected wave top, it may be a wellbore mode reflected wave caused by the formation interface.

[0093] (3) Otherwise, it may be a wellbore mode reflection wave caused by formation fractures.

[0094] The wellbore pattern reflection wave identification method provided by this invention is applied to a certain well, such as... Figure 3 The image shows the far monopole of a certain well. Figure 4 This is a density plot of the four-component, equal-source-spacing waveform of an orthogonal dipole well. The first channel is the original waveform of the far monopole, the second channel is the far monopole waveform after bandpass filtering, and the third to sixth channels are the dipole XX, YY, XY and YX component waveforms after bandpass filtering, respectively.

[0095] It can be seen that the characteristics of wellbore mode waves such as gliding P-waves, gliding S-waves, Stoneley waves, and dipole waves are clear and their arrival is obvious. The green dashed lines mark the more obvious upward reflection waves in the far-field probe wave field of the dipole XX component. These upward reflection waves have similar slopes, extend for a long time, and their tops coincide with the wellbore mode waves. The blue dashed lines mark the more obvious downward reflection waves in the far-field probe wave field of the dipole XX component. These downward reflection waves also have similar slopes, extend for a long time, and their tops coincide with the wellbore mode waves. The upward and downward reflection waves marked by the green and blue dashed lines exhibit a "V" shape feature. Through calculation, the slope value of the "V" shaped reflection wave is about half of the formation S-wave velocity. Similar "V" shaped reflection features are also shown in the waveforms of the remaining channels. Among them, the "V" shaped reflection waveform in the original far-monopolar waveform of the first channel is a low-frequency Stoneley wave reflection wave.

[0096] Two typical depth points were selected, and single-shot waveform diagrams were plotted. The array waveforms were processed using the slow-time correlation method. Single-shot waveform data at depths of 7525m and 7542m were analyzed, respectively. Figures 5 to 12 As shown. Figures 5 to 8 As shown, for both the far monopole waveform and the dipole XX component waveform, there is a significant upward reflection wave around 6 ms. From the STC coherence plot, it can be seen that the apparent velocity of this upward reflection wave is close to the formation shear wave velocity, indicating it is a reflected shear wave propagating along the well axis. Figures 9 to 12 As shown, for both the far monopole waveform and the dipole XX component waveform, there is a significant downward reflection wave around 4ms, as indicated by the STC coherence plot ( Figure 6 , Figure 8 , Figure 10 , Figure 12 As can be seen from the above, the apparent velocity of the reflected wave is close to the formation shear wave velocity, indicating that it is a reflected shear wave propagating along the well axis. In summary, Figure 3 and Figure 4The "V"-shaped reflected waves in the second to sixth channels are actually wellbore mode reflected transverse waves propagating along the well axis.

[0097] Example 2

[0098] This embodiment provides a computer-readable storage medium storing a computer program. When the computer program is executed by a processor, it implements the wellbore pattern reflection wave identification method provided in Embodiment 1.

[0099] Example 3

[0100] This embodiment provides a method for suppressing wellbore mode reflected waves, which suppresses reflected waves identified using the wellbore mode reflected wave identification method provided in Embodiment 1. Figure 13 As shown, the pressing methods include:

[0101] Step 1: Delay and gain recovery for the equidistant waveform;

[0102] Step 2: Perform bandpass filtering on the equidistant waveform to suppress low-frequency Stoneley waves, direct waves, and reflected waves, as well as high-frequency noise in the wave field;

[0103] Step 3: Using the slope of the borehole mode reflected wave in the variable density diagram of the equal source spacing waveform as a reference, set the velocity range parameter and perform the first filtering on the equal source spacing waveform to suppress the borehole mode reflected wave in the wave field.

[0104] The first filtering is fk filtering, and the fk filtering calculation method is as follows:

[0105]

[0106] In the above formula, w1(t,z) is the equal-source-distance waveform data in the time-depth-z domain, W1(f,k) is the data transformed to the frequency-wavenumber-k domain, L(f,k) is the filter in the frequency-wavenumber-k domain, w2(t,x) is the equal-source-distance waveform data after fk filtering, and vlen is the set velocity range parameter.

[0107] Step 4: Using the apparent velocity v0 of the borehole mode reflected wave in the single-shot waveform at a typical depth point as a reference, set the velocity range and perform a second filtering on the single-shot waveform to suppress the borehole mode reflected wave in the wave field.

[0108] The set speed range v is:

[0109] v0-vlen≤v≤v0+vlen

[0110] In the above formula, v is the set speed range, within which the single-shot waveform is filtered a second time.

[0111] The second filtering is median filtering, and the median filtering method is as follows:

[0112]

[0113] w' j (v,t)=w j (t+τ j (v))

[0114]

[0115] w' j '(v,t)=w med (v,t-τ j (v))

[0116]

[0117] In the formula, vlen is the set speed range parameter; d c d represents the source distance of the middle channel waveform. j τ is the source distance of the j-th waveform. j (v) represents the time shift between the j-th and intermediate channel waveforms, w j (t) represents the original waveform, w' j (v,t) represents the waveform after time shift with v as the velocity parameter, w med (v,t) represents the waveform after taking the median of the time-shifted waveform, w' j (v,t) represents the waveform after inverse time shifting the median waveform. The waveform data of the suppressed wellbore mode reflected wave is obtained by subtracting the time-shifted waveform from the original waveform.

[0118] Example 4

[0119] This embodiment provides a computer-readable storage medium storing a computer program, which, when executed by a processor, implements the wellbore mode reflected wave suppression method provided in Embodiment 3.

[0120] This invention can identify and suppress borehole mode reflected waves in the acoustic remote sensing wave field, highlight the effective reflected waves from the anomalous body near the well, suppress large-amplitude artifacts in the remote sensing imaging image, and improve the imaging signal-to-noise ratio.

[0121] The above specific embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit it. Although the present invention has been described in detail with reference to examples, those skilled in the art should understand that modifications or equivalent substitutions can be made to the technical solutions of the present invention without departing from the scope of the technical solutions of the present invention, and all such modifications or substitutions should be covered within the scope of the claims of the present invention.

Claims

1. A method for identifying wellbore mode reflected waves, characterized in that, include: Step 1: Draw the original equal-source-spacing waveform density diagram in the far-monopolar operating mode and observe whether there are low-frequency reflected Stoneley waves in the wave field; Step 2: Perform bandpass filtering on the array waveforms in both monopole and quadrature dipole operating modes; Step 3: Draw the variable density diagrams of the equal source distance waveforms after bandpass filtering in both far monopole and orthogonal dipole modes, and observe whether there are up-going or down-going reflected waves in the wave field. Step 4: Calculate the slope of the upward or downward reflected wave in the variable density diagram of the equal source spacing waveform; Step 5: Select one depth point, draw the single-shot waveform diagram of the up-going or down-going reflected wave, process the single-shot waveform diagram, and calculate the apparent velocity of the up-going or down-going reflected wave. Step 6: Determine whether the upward or downward reflected wave is a wellbore mode reflected wave interference wave in the acoustic remote sensing wave field.

2. The identification method according to claim 1, characterized in that, The slope in step 4 is calculated as follows: In the above formula, slope is the slope, the horizontal axis of the equal-source-distance waveform variable density map is time t, the vertical axis is depth z, (t1,z1) and (t2,z2) are the coordinates of any two points P1 and P2 on the reflected wave in the equal-source-distance waveform variable density map, and α is the angle between the reflected wave and the time t axis.

3. The identification method according to claim 1, characterized in that, In step 5, the single-shot waveform is processed using the slow-time correlation method. The specific calculation method is as follows: in, In the above formula, ρ is the waveform correlation coefficient, v0 is the apparent velocity, τ is time, M is the waveform channel number, m is the waveform channel number, and T is the waveform correlation coefficient. w X is the time window length. m d represents the m-th waveform data, and d represents the spacing between logging instruments.

4. The identification method according to claim 1, characterized in that, In step 6, it is determined whether the uplink or downlink reflected wave is a wellbore mode reflected wave interference wave in the acoustic remote sensing wave field. The specific method is as follows: If either the uplink or downlink reflected wave simultaneously meets the following conditions, it is considered a wellbore mode reflected wave interference wave in the acoustic remote sensing wave field: (1) The reflected wave extends in time and coincides with the top and wellbore mode wave; (2) Low-frequency reflected Stoneley waves exist at the depth where the top of the reflected wave is located; (3) The slope of the reflected wave in the equal source distance waveform density diagram is equal to half of the formation shear wave velocity, or the apparent velocity of the reflected wave in the single shot waveform is equal to the formation shear wave velocity.

5. The identification method according to claim 1, characterized in that, Methods for identifying borehole mode reflected waves also include: Step 7: Combine conventional logging curves to analyze the causes of borehole mode reflection waves in the acoustic remote detection wave field.

6. A computer-readable storage medium, characterized in that, The storage medium stores a computer program, which, when executed by a processor, implements the method for identifying borehole pattern reflected waves as described in any one of claims 1-5.

7. A method for suppressing wellbore mode reflected waves, comprising suppressing reflected waves identified by the wellbore mode reflected wave identification method according to any one of claims 1-5, characterized in that, Suppression methods include: Step 1: Delay and gain recovery for the equidistant waveform; Step 2: Perform bandpass filtering on the waveform with equal source spacing; Step 3: Using the slope of the reflected wave in the borehole mode in the variable density diagram of the equal source spacing waveform as a reference, set the velocity range parameter and perform the first filtering on the equal source spacing waveform; Step 4: Using the apparent velocity v0 of the borehole mode reflected wave in the single-shot waveform at a typical depth point as a reference, set the velocity range and perform a second filtering on the single-shot waveform.

8. The pressing method according to claim 7, characterized in that, The first filtering step in step three is fk filtering.

9. The pressing method according to claim 8, characterized in that, The calculation method for fk filtering is as follows: In the above formula, w1(t,z) is the equal-source-distance waveform data in the time-depth-z domain, W1(f,k) is the data transformed to the frequency-wavenumber-k domain, L(f,k) is the filter in the frequency-wavenumber-k domain, w2(t,x) is the equal-source-distance waveform data after fk filtering, and vlen is the set velocity range parameter.

10. The pressing method according to claim 9, characterized in that, Step four involves setting the speed range, specifically as follows: v0-vlen≤v≤v0+vlen In the above formula, v is the set speed range, within which the single-shot waveform is filtered a second time.

11. The pressing method according to claim 10, characterized in that, The second filtering step in step four is median filtering.

12. The pressing method according to claim 11, characterized in that, The calculation method for median filtering is as follows: w' j (v,t)=w j (t+τ j (v)) w″ j (v,t)=w med (v,t-τ j (v)) In the formula, vlen is the set speed range parameter; d c d represents the source distance of the middle channel waveform. j τ is the source distance of the j-th waveform. j (v) represents the time shift between the j-th and intermediate channel waveforms, w j (t) represents the original waveform, w' j (v,t) represents the waveform after time shift with v as the velocity parameter, w med (v,t) represents the waveform after taking the median of the time-shifted waveform, w″ j (v,t) represents the waveform after inverse time shifting the median waveform. The waveform data of the suppressed wellbore mode reflected wave is obtained by subtracting the time-shifted waveform from the original waveform.

13. A computer-readable storage medium storing a computer program thereon, characterized in that, When the computer program is executed by the processor, it implements the method for suppressing well-mode reflected waves according to any one of claims 7-12.

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