Method for determining geologic horizon of PSV wave seismic event

Abstract

The invention discloses a method for determining a geologic horizon of a PSV wave seismic event, and relates to the technical field of petroleum and natural gas exploration and development, and the method comprises the following steps: S1, carrying out the rotation orientation processing of a horizontal component and a vertical component; s2, extracting an upgoing wave field of the PSV wave; s3, non-zero offset PSV wave imaging and non-zero offset PSV wave corridor superposition are carried out; s4, determining the geologic horizon of the PSV wave corridor stacked section; and S5, determining the geologic horizon of the three-dimensional seismic PSV wave event. According to the method, a high-precision extraction method of the non-zero offset PSV upgoing wave field is innovated, and effective separation of the complex wave field is ensured; meanwhile, a new corridor stacked section manufacturing method and a new geologic horizon determining method are created, the situation that logging curve missing and environmental quality affect the reliability of geologic horizon determination is avoided, the problem that calibration difficulty is large due to the fact that zero-offset PSV wave signals are weak is solved, more reasonable PSV wave geologic horizon determination can be obtained, and the accuracy of geologic horizon determination is improved. And a basic guarantee is provided for multi-wave multi-component oil gas earthquake prediction application.

Description

Technical Field

[0001] This invention relates to the field of oil and gas exploration and development technology, and more specifically to a method for determining the geological strata of PSV wave seismic phase axes. Background Technology

[0002] As oil and gas exploration and development deepens, it continues to expand into deeper, low-permeability, and unconventional areas. However, in these areas, the reservoir and surrounding rock properties are very similar, the gas-water relationship is complex, and the heterogeneity is strong. Conventional P-wave data is a comprehensive response to the characteristics of the subsurface rock framework, pores, and fluids, thus exhibiting ambiguity. S-waves, on the other hand, are only related to the rock framework and pores, and are independent of fluid properties. Therefore, the combined application of P-wave and S-wave data can reduce the ambiguity in reservoir and gas-bearing predictions. Currently, the industry commonly uses P-wave source excitation and digital three-component geophones to obtain P-waves and PSVs, and their combined application reduces the ambiguity in reservoir and gas-bearing predictions. The key to the successful application of the combined P-wave and PSV data lies in the accurate determination of the geological stratigraphic position of the PSV wave seismic phase axis.

[0003] Currently, the geological strata of the PSV wave seismic phase axis are mainly determined by well logging composite records and zero-biased VSP corridor stacked profiles.

[0004] The method of determining geological strata using well logging composite records involves calculating the PSV wave reflection coefficient sequence for different shot-receiver offsets based on the PSV wave reflection coefficient formula. These PSV wave reflection coefficient sequences are then summed to obtain a PSV wave reflection coefficient sequence identical to the actual overlay trace. This sequence is then convolved with a selected seismic wavelet to obtain the PSV wave composite record. The geological strata at the PSV wave seismic phase axis are determined by calibrating the PSV wave composite record with the PSV wave seismic phase axis. However, this method requires full-wavelength logging data and is susceptible to the reliability of geological strata determination due to missing logging curves and environmental quality factors.

[0005] The second method is the zero-biased VSP corridor stacking profile. This method uses zero-biased three-component VSP data to extract the PSV wave upriding profile, obtains the corridor stacking profile, and uses bridge correlation to determine the geological stratigraphic level. This method uses zero-biased VSP data, and due to the small angle, the PSV wave signal is weak, making it difficult to obtain high-quality PSV waves.

[0006] Therefore, there is an urgent need to develop a more stable method for determining the geological stratigraphic position of PSV wave seismic phase axes to solve the above problems. Summary of the Invention

[0007] To overcome the shortcomings of the existing technology, the present invention aims to provide a method for determining the geological strata of PSV wave seismic phase axes. This method innovates a high-precision extraction method for non-zero bias PSV upriding wave fields, ensuring effective separation of complex wave fields. At the same time, it creates a new method for constructing corridor stacked profiles and a method for determining geological strata. This not only avoids the impact of missing logging curves and environmental quality on the reliability of geological strata determination, but also avoids the problem of difficult calibration caused by weak zero bias PSV wave signals. It can obtain more reasonable PSV wave geological strata determination, providing a basic guarantee for multi-wave multi-component oil and gas seismic prediction applications, thereby improving the success rate of oil and gas exploration.

[0008] To achieve the above objectives, the technical solution adopted by the present invention is as follows:

[0009] A method for determining the geological stratigraphic position of PSV wave seismic phase axes includes the following steps:

[0010] I. Rotational Orientation Processing of Horizontal and Vertical Components

[0011] S1. Rotate and orient the horizontal and vertical components of the non-zero bias VSP three-component data to obtain the component V0 in the ray direction in the vertical plane and the component VT perpendicular to that direction.

[0012] Step S1 performs rotational orientation processing on the horizontal and vertical components. The non-zero bias VSP three-component data (Z, X, and Y components) undergoes horizontal and vertical component rotational orientation processing to obtain the component V0 in the vertical plane along the ray direction and the component VT perpendicular to that direction. VSP refers to the vertical seismic profile.

[0013] Step S1 includes the following steps:

[0014] S11. Pick the first arrival of the Z component of the non-zero bias VSP three-component data, select the first cycle time of the first arrival, and substitute the amplitude of the corresponding X and Y components into the formula for the horizontal rotation orientation angle to calculate the horizontal rotation orientation angle.

[0015] In step S11, the formula for the horizontal rotation orientation angle is:

[0016]

[0017] Where θ is the horizontal rotation orientation angle; i is the time sequence number of the non-zero bias VSP three-component data within the calculation window; x i The X component of point i in the non-zero bias VSP three-component data; y i The Y component of point i in the non-zero bias VSP three-component data.

[0018] S12. For the X and Y components of the non-zero bias VSP three-component data, according to the horizontal component orientation formula and combined with the horizontal rotation orientation angle obtained in step S11, the X and Y components are horizontally oriented to obtain the component H0 in the well source direction and the direction component HT perpendicular to the well source direction.

[0019] In step S12, the horizontal component orientation formula is:

[0020]

[0021] Where H0 is the well source direction component, HT is the component perpendicular to the well source direction, X is the X component of the non-zero bias VSP three-component data, Y is the Y component of the non-zero bias VSP three-component data, and θ is the horizontal rotation orientation angle.

[0022] S13. For the Z component of the non-zero bias VSP three-component data and the H0 component obtained in step S12, calculate the vertical component rotation orientation angle according to the vertical component rotation orientation angle formula.

[0023] In step S13, the formula for the vertical component rotation orientation angle is:

[0024]

[0025] Where φ is the rotation orientation angle of the vertical component; i is the time sequence number of the non-zero bias VSP three-component data within the calculation window; H0 i The H0 component of point i in the non-zero bias VSP three-component data; Z i The Z component of point i in the non-zero bias VSP three-component data.

[0026] S14. For the Z component of the non-zero bias VSP three-component data and the H0 component obtained in step S12, according to the vertical component orientation formula and combined with the vertical component rotation orientation angle obtained in step S13, the Z and H0 components are vertically oriented to obtain the component V0 of the ray direction in the vertical plane and the component VT perpendicular to the ray direction in the vertical plane.

[0027] In step S14, the vertical component orientation formula is:

[0028]

[0029] Wherein, V0 is the ray direction component in the vertical plane; VT is the component perpendicular to the ray direction in the vertical plane; Z is the Z component of the non-zero bias VSP three-component data; H0 is the H0 component of the non-zero bias VSP three-component data; and φ is the rotation orientation angle of the vertical component.

[0030] II. PSV wave upward wave field extraction

[0031] S2. Separate the ascending and descending waves of components V0 and VT to obtain the ascending wave field V0. 上 and the upward wave field VT 上 The time-varying method was used to obtain and extract the PSV wave field;

[0032] Step S2 includes: using median filtering and FK separation methods to separate the ascending and descending waves in the component V0 of the ray direction perpendicular to the plane and the component VT perpendicular to that direction, obtaining the ascending wave field of V0 and the ascending wave field of VT, denoted as V0 and V0 respectively. 上 and VT 上 .

[0033] In this invention, due to V0 上 and VT 上 Since both upward wave fields are denoted as being mixed with P-wave and PSV-wave upward wave fields, a time-varying method is adopted to obtain and extract the PSV-wave upward wave field according to the following formula.

[0034] In step S2, the time-varying method includes:

[0035] P-SV 上行 =-V0 上 sinθ(t)+VT 上 cosθ(t);

[0036] Where P is the P-wave ascending wave field; SV 上行 For the SV wave ascending wave field; V0 上 For component V0, the upward wave field; VT 上 VT represents the upward wave field of component VT; θ represents the horizontal rotation orientation angle; and t represents time.

[0037] III. Non-zero bias PSV wave imaging and superposition of non-zero bias PSV wave corridors

[0038] S3. Image the non-zero bias PSV wave to obtain the PSV wave VSP-CDP superimposed profile in the time domain of the PP wave, and superimpose the superimposed profile near the wellhead to obtain the corridor superimposed profile of the non-zero bias PSV wave.

[0039] Step S3 includes the following steps:

[0040] S31. Use the velocities of P-wave and S-wave to create a velocity model of PSV wave, and use the velocity model to spatially reorient the PSV wave to obtain a PSV wave VSP-CDP superposition profile. Then convert the superposition profile to the time domain of PP wave to obtain a PSV wave VSP-CDP superposition profile in the time domain of PP wave.

[0041] S32. The PSV wave VSP-CDP superposition profile in the time domain of the PP wave is superimposed near the wellhead to obtain a corridor superposition profile similar to the zero well source distance P wave, which is used as the corridor superposition profile of the non-zero bias PSV wave.

[0042] IV. Determining the geological stratigraphy of the PSV wave corridor superimposed profile

[0043] S4. Combine the PSV wave up-row field to determine the geological strata of the PSV wave corridor superposition profile;

[0044] Step S4 includes the following steps:

[0045] S41. Based on the geological strata revealed by the drilling data, and according to the depth, correspond to the PSV wave upward wave field to identify the main geological strata of the PSV wave upward wave field.

[0046] S42. Calculate and calibrate the phase axis of the PSV wave uphill wave field near the wellhead using the PSV wave velocity model, and the location of the corresponding PSV wave VSP-CDP superimposed profile. Combine this with the main geological strata of the PSV wave uphill wave field determined in step S41 to calibrate the geological strata of the PSV wave VSP-CDP superimposed profile.

[0047] S43. Based on the geological strata of the VSP-CDP superimposed profile of the PSV wave, determine the geological strata of the corridor superimposed profile of the PSV wave at the same location.

[0048] V. Determining the geological stratigraphic position of the three-dimensional seismic PSV wave phase axis

[0049] S5. Using the geological strata of the PSV wave corridor superposition profile, determine the geological strata of the three-dimensional seismic PSV wave phase axis.

[0050] The S5 step includes the following steps:

[0051] S51. Insert the corridor stacking profile of the non-zero bias PSV wave into the location of the 3D seismic well bypass. The geological strata determined by the corridor stacking profile of the non-zero bias PSV wave are used to introduce the phase axis of the 3D seismic PSV wave well bypass to determine the geological strata of the phase axis of the 3D seismic well bypass.

[0052] S52. Starting from the phase axis of the PSV wave well bypass, calculate the correlation coefficient of the adjacent traces for the phase axis for which the geological strata need to be determined. According to the maximum value of the correlation coefficient, carry out automatic strata tracking in the whole area to obtain the geological strata distribution in the whole area, that is, determine the geological strata of the target three-dimensional seismic layer in the whole area.

[0053] The beneficial effects of this invention are:

[0054] This invention innovates a high-precision extraction method for non-zero bias PSV ascending wave fields, ensuring effective separation of complex wave fields. Simultaneously, it establishes new methods for creating corridor overlay profiles and determining geological strata. This not only avoids the impact of missing logging curves and environmental quality on the reliability of geological strata determination, but also avoids the calibration difficulties caused by weak zero bias PSV wave signals. It enables more reasonable PSV wave geological strata determination, providing a fundamental guarantee for multi-wave, multi-component oil and gas seismic prediction applications, thereby improving the success rate of oil and gas exploration. Furthermore, this invention provides important support for the combined application of PP waves and PSV waves to improve drilling success rates.

[0055] This invention has been applied to multi-wave, multi-component seismic exploration and development of oil and gas in the Sichuan Basin. Addressing the challenge of determining geological strata along PSV wave phase axes, this invention not only solves the problems of missing logging curves and environmental quality affecting the reliability of geological strata determination, but also avoids the difficulty in determining geological strata caused by weak zero-bias PSV wave signals, enabling accurate determination of PSV wave geological strata. Reservoirs predicted using this method have improved the accuracy of thin-layer identification, effectively guiding well location deployment. All four wells that have been implemented have successfully obtained industrial gas flow. Attached Figure Description

[0056] Figure 1 This is a design flowchart of the present invention;

[0057] Figure 2 This is the PSV wave up-traveling field extracted in this invention;

[0058] Figure 3 This is the VSP-CDP superposition profile and corridor superposition profile of the non-zero bias PSV wave of the present invention;

[0059] Figure 4 To determine the geological stratigraphic position of the PSV wave ascending field in this invention;

[0060] Figure 5 This invention provides a method for determining the geological stratigraphic position of the PSV wave VSP-CDP profile.

[0061] Figure 6 This invention is used to determine the geological strata of the non-zero bias PSV wave corridor superimposed profile. Detailed Implementation

[0062] The following will provide a clear and complete description of the concept, specific structure, and technical effects of the present invention in conjunction with the embodiments and accompanying drawings, so as to fully understand the purpose, features, and effects of the present invention.

[0063] A method for determining geological strata based on PSV wave seismic phase axes provides important support for improving drilling success rates through the combined application of PP and PSV waves.

[0064] like Figure 1 As shown, the specific embodiments of the present invention are as follows:

[0065] S1. Rotational orientation processing of horizontal and vertical components;

[0066] S2. PSV wave upward wave field extraction;

[0067] S3. Non-zero bias PSV wave imaging superimposed with non-zero bias PSV wave corridor;

[0068] S4. Determine the geological stratigraphic position of the PSV wave corridor superimposed profile;

[0069] S5. Determine the geological horizon of the PSV wave phase axis in three-dimensional seismic waves.

[0070] Taking a three-dimensional multi-wave seismic study of a certain block in the Sichuan Basin as an example, this invention will be further explained. In the following description, the certain block in the Sichuan Basin will be referred to as the study area. The specific process is carried out according to the following steps:

[0071] S1. Rotation and orientation processing of horizontal and vertical components: For the non-zero bias VSP three-component data, namely the Z component, X component, and Y component, perform horizontal and vertical component rotation and orientation according to steps S11-S14 to obtain the component V0 in the ray direction in the vertical plane and the component VT perpendicular to that direction.

[0072] Step S1 includes the following steps:

[0073] S11. Pick the first arrival of the Z component of the non-zero bias VSP three-component data, select the first cycle time of the first arrival, and substitute the amplitude of the corresponding X and Y components into the formula for the horizontal rotation orientation angle to calculate the horizontal rotation orientation angle.

[0074] In step S11, the formula for the horizontal rotation orientation angle is:

[0075]

[0076] Where θ is the horizontal rotation orientation angle; i is the time sequence number of the non-zero bias VSP three-component data within the calculation window; x i The X component of point i in the non-zero bias VSP three-component data; y i The Y component of point i in the non-zero bias VSP three-component data.

[0077] S12. For the X and Y components of the non-zero bias VSP three-component data, according to the horizontal component orientation formula and combined with the horizontal rotation orientation angle obtained in step S11, the X and Y components are horizontally oriented to obtain the component H0 in the well source direction and the direction component HT perpendicular to the well source direction.

[0078] In step S12, the horizontal component orientation formula is:

[0079]

[0080] Where H0 is the well source direction component, HT is the component perpendicular to the well source direction, X is the X component of the non-zero bias VSP three-component data, Y is the Y component of the non-zero bias VSP three-component data, and θ is the horizontal rotation orientation angle.

[0081] S13. For the Z component of the non-zero bias VSP three-component data and the H0 component obtained in step S12, calculate the vertical component rotation orientation angle according to the vertical component rotation orientation angle formula.

[0082] In step S13, the formula for the vertical component rotation orientation angle is:

[0083]

[0084] Where φ is the rotation orientation angle of the vertical component; i is the time sequence number of the non-zero bias VSP three-component data within the calculation window; H0 i The H0 component of point i in the non-zero bias VSP three-component data; Z i The Z component of point i in the non-zero bias VSP three-component data.

[0085] S14. For the Z component of the non-zero bias VSP three-component data and the H0 component obtained in step S12, according to the vertical component orientation formula and combined with the vertical component rotation orientation angle obtained in step S13, the Z and H0 components are vertically oriented to obtain the component V0 of the ray direction in the vertical plane and the component VT perpendicular to the ray direction in the vertical plane.

[0086] In step S14, the vertical component orientation formula is:

[0087]

[0088] Wherein, V0 is the ray direction component in the vertical plane; VT is the component perpendicular to the ray direction in the vertical plane; Z is the Z component of the non-zero bias VSP three-component data; H0 is the H0 component of the non-zero bias VSP three-component data; and φ is the rotation orientation angle of the vertical component.

[0089] S2. PSV wave uphill wave field extraction. Using median filtering and the FK separation method, the uphill and downhill waves in the component V0 along the ray direction in the vertical plane and the component VT perpendicular to that direction are separated, obtaining the V0 uphill wave field and the VT uphill wave field, denoted as V0 and VT respectively. 上 and VT 上 Due to V0 上 and VT 上Let's denote two ascending wave fields, each containing a mixture of P-wave and PSV-wave ascending wave fields. The PSV-wave ascending wave field can be calculated and extracted using the following formula: Figure 2 As shown.

[0090] P-SV 上行 =-V0 上 sinθ(t)+VT 上 cosθ(t);

[0091] Where P is the P-wave ascending wave field; SV 上行 For the SV wave ascending wave field; V0 上 For component V0, the upward wave field; VT 上 VT represents the upward wave field of component VT; θ represents the horizontal rotation orientation angle; and t represents time.

[0092] S3. Non-zero bias PSV wave imaging and superposition of non-zero bias PSV wave corridor

[0093] S31. Non-zero bias PSV wave imaging

[0094] A velocity model for the PSV wave was constructed using P-wave and S-wave velocities. This model was then used to spatially reorient the PSV wave, yielding a PSV wave VSP-CDP stacking profile. Simultaneously, this profile was converted to the PP wave time domain, resulting in a PSV wave VSP-CDP stacking profile in the PP wave time domain. Figure 3 As shown on the left.

[0095] S32. Non-zero bias PSV wave corridor superposition

[0096] By stacking the PSV wave VSP-CDP stacking profile near the wellhead, a corridor stacking profile similar to the zero-source-pitch P-wave is obtained, which is called the corridor stacking profile of the non-zero-bias PSV wave. Figure 3 As shown on the right.

[0097] S4. Determine the geological stratigraphic position of the PSV wave corridor overlay profile.

[0098] S41. Determine the geological stratigraphic position of the PSV wave ascending wave field.

[0099] By correlating the geological strata revealed by drilling data with the depths corresponding to the PSV wave updraft field, the main geological strata of the PSV wave updraft field are identified, such as... Figure 4 As shown.

[0100] S42. Determine the geological stratigraphic position of the VSP-CDP superimposed profile of the PSV wave.

[0101] Following step S31, the phase axis of the PSV wave ascending wave field near the wellhead can be calculated and calibrated, corresponding to the location of the VSP-CDP stacked profile of the PSV wave. The geological strata of the VSP-CDP stacked profile of the PSV wave can then be calibrated, such as... Figure 5 As shown.

[0102] S43. Determine the geological strata of the corridor superposition profile of the PSV wave.

[0103] The geological strata of the P-SV wave VSP-CDP superimposed profile are determined by matching the locations of the PSV wave corridor superimposed profiles, such as... Figure 6 As shown.

[0104] S5. Determine the geological horizon of the 3D seismic PSV wave phase axis.

[0105] S51. Determine the geological strata of the 3D seismic PSV waveguide bypass.

[0106] The corridor stacking profile of non-zero bias PSV waves is inserted into the location of the 3D seismic well bypass. The geological strata determined by the corridor stacking profile of non-zero bias PSV waves are then introduced into the corresponding phase axis of the 3D seismic PSV wave well bypass, thus determining the geological strata of the 3D seismic well bypass phase axis.

[0107] S52. Determine the geological stratigraphic position of the full-area in-phase axis of the 3D seismic PSV wave.

[0108] Starting from the phase axis of the PSV wave well bypass, the correlation coefficient of the adjacent traces is calculated for the phase axis for which the geological strata need to be determined. The entire area is automatically tracked according to the largest correlation coefficient to obtain the geological strata distribution of the entire area, thus determining the geological strata of the target three-dimensional seismic layer in the entire area.

[0109] The embodiments of the present invention have been described in detail above, but the present invention is not limited to the described embodiments. Those skilled in the art can make various equivalent modifications or substitutions without departing from the spirit of the present invention, and these equivalents or substitutions are all included within the scope defined by the claims of the present invention.

Claims

1. A method for determining the geological stratigraphic position of a PSV wave seismic phase axis, characterized in that, Includes the following steps: S1. Rotate and orient the horizontal and vertical components of the non-zero bias VSP three-component data to obtain the component V0 in the ray direction in the vertical plane and the component VT perpendicular to that direction. S2, separating the upgoing and downgoing waves of the component V0 and the component VT to obtain the upgoing wave field V0 上 and the upgoing wave field VT 上 and using the time-varying method, obtaining and extracting the upgoing wave field of the PSV wave; S3. Image the non-zero bias PSV wave to obtain the PSV wave VSP-CDP superimposed profile in the time domain of the PP wave, and superimpose the superimposed profile near the wellhead to obtain the corridor superimposed profile of the non-zero bias PSV wave. S4. Combine the PSV wave up-row field to determine the geological strata of the PSV wave corridor superposition profile; S5. Using the geological strata of the PSV wave corridor superposition profile, determine the geological strata of the three-dimensional seismic PSV wave phase axis.

2. The method for determining geological stratigraphy as described in claim 1, characterized in that, Step S1 includes the following steps: S11. Pick the first arrival of the Z component of the non-zero bias VSP three-component data, select the first cycle time of the first arrival, and substitute the amplitude of the corresponding X and Y components into the formula for the horizontal rotation orientation angle to calculate the horizontal rotation orientation angle. S12. For the X and Y components of the non-zero bias VSP three-component data, according to the horizontal component orientation formula and combined with the horizontal rotation orientation angle obtained in step S11, the X and Y components are horizontally oriented to obtain the component H0 in the well source direction and the direction component HT perpendicular to the well source direction. S13. For the Z component of the non-zero bias VSP three-component data and the H0 component obtained in step S12, calculate the vertical component rotation orientation angle according to the vertical component rotation orientation angle formula. S14. For the Z component of the non-zero bias VSP three-component data and the H0 component obtained in step S12, according to the vertical component orientation formula and combined with the vertical component rotation orientation angle obtained in step S13, the Z and H0 components are vertically oriented to obtain the component V0 of the ray direction in the vertical plane and the component VT perpendicular to the ray direction in the vertical plane.

3. The method for determining geological stratigraphy as described in claim 2, characterized in that, In step S11, the formula for the horizontal rotation orientation angle is: wherein, θ is the horizontal rotation orientation angle; i is the time serial number of the non-deviated VSP three-component data in the calculation time window; x i is the X component of the non-deviated VSP three-component data i point; y i is the Y component of the non-deviated VSP three-component data i point.

4. The method for determining geological stratigraphy as described in claim 2, characterized in that, In step S12, the horizontal component orientation formula is: Where H0 is the well source direction component, HT is the component perpendicular to the well source direction, X is the X component of the non-zero bias VSP three-component data, Y is the Y component of the non-zero bias VSP three-component data, and θ is the horizontal rotation orientation angle.

5. The method for determining geological stratigraphy as described in claim 2, characterized in that, In step S13, the formula for the vertical component rotation orientation angle is: Where φ is the rotation orientation angle of the vertical component; i is the time sequence number of the non-zero bias VSP three-component data within the calculation window; H0 i The H0 component of point i in the non-zero bias VSP three-component data; Z i The Z component of point i in the non-zero bias VSP three-component data.

6. The method for determining geological stratigraphy as described in claim 2, characterized in that, In step S14, the vertical component orientation formula is: Wherein, V0 is the ray direction component in the vertical plane; VT is the component perpendicular to the ray direction in the vertical plane; Z is the Z component of the non-zero bias VSP three-component data; H0 is the H0 component of the non-zero bias VSP three-component data; and φ is the rotation orientation angle of the vertical component.

7. The method for determining geological stratigraphy as described in claim 1, characterized in that, Step S2 includes: using median filtering and FK separation methods to separate the ascending and descending waves in the component V0 of the ray direction perpendicular to the plane and the component VT perpendicular to that direction, obtaining the ascending wave field of V0 and the ascending wave field of VT, denoted as V0 and V0 respectively. 上 and VT 上 ; In step S2, the time-varying method includes: P-SV 上行 =-V0 上 sinθ(t)+VT 上 cosθ(t); Where P is the P-wave ascending wave field; SV 上行 For the SV wave ascending wave field; V0 上 For component V0, the upward wave field; VT 上 VT represents the upward wave field of component VT; θ represents the horizontal rotation orientation angle; and t represents time.

8. The method for determining geological stratigraphy as described in claim 1, characterized in that, Step S3 includes the following steps: S31. Use the velocities of P-wave and S-wave to create a velocity model of PSV wave, and use the velocity model to spatially reorient the PSV wave to obtain a PSV wave VSP-CDP superposition profile. Then convert the superposition profile to the time domain of PP wave to obtain a PSV wave VSP-CDP superposition profile in the time domain of PP wave. S32. The PSV wave VSP-CDP superposition profile in the time domain of the PP wave is superimposed near the wellhead to obtain a corridor superposition profile similar to the zero well source distance P wave, which is used as the corridor superposition profile of the non-zero bias PSV wave.

9. The method for determining geological stratigraphy as described in claim 8, characterized in that, Step S4 includes the following steps: S41. Based on the geological strata revealed by the drilling data, and according to the depth, correspond to the PSV wave upward wave field to identify the main geological strata of the PSV wave upward wave field. S42. Calculate and calibrate the phase axis of the PSV wave uphill wave field near the wellhead using the PSV wave velocity model, and the location of the corresponding PSV wave VSP-CDP superimposed profile. Combine this with the main geological strata of the PSV wave uphill wave field determined in step S41 to calibrate the geological strata of the PSV wave VSP-CDP superimposed profile. S43. Based on the geological strata of the VSP-CDP superimposed profile of the PSV wave, determine the geological strata of the corridor superimposed profile of the PSV wave at the same location.

10. The method for determining geological stratigraphy as described in claim 1, characterized in that, The S5 step includes the following steps: S51. Insert the corridor stacking profile of the non-zero bias PSV wave into the location of the 3D seismic well bypass. The geological strata determined by the corridor stacking profile of the non-zero bias PSV wave are used to introduce the phase axis of the 3D seismic PSV wave well bypass to determine the geological strata of the phase axis of the 3D seismic well bypass. S52. Starting from the phase axis of the PSV wave well bypass, calculate the correlation coefficient of the adjacent traces for the phase axis for which the geological strata need to be determined. According to the maximum value of the correlation coefficient, carry out automatic strata tracking in the whole area to obtain the geological strata distribution in the whole area, that is, determine the geological strata of the target three-dimensional seismic layer in the whole area.

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