Ground seismic P-S wave three-domain matching method, electronic device and medium
By using VSP data processing and common-resolution filtering technology, the problem of low matching accuracy of P-waves and S-waves was solved, achieving high-precision matching of P-wave and S-wave profiles as a whole, and providing a reliable basis for joint interpretation of P-waves and S-waves.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- CHINA NAT PETROLEUM CORP
- Filing Date
- 2023-12-27
- Publication Date
- 2026-04-14
AI Technical Summary
Existing technologies suffer from significant differences between P-wave and S-wave profiles, low signal-to-noise ratio in S-wave data, and compression factors that fail to represent the overall velocity ratio in P-wave and S-wave matching, resulting in low matching accuracy and making it difficult to achieve high-precision overall matching.
By processing VSP data, velocity models of P-waves and S-waves with different velocities at the same depth are established. Time-depth conversion and depth domain matching are performed. Frequency matching is achieved using common-resolution filtering. Combined with VSP same-depth frequency band scanning and the optimal velocity model, three-domain matching of P-waves and S-waves is performed.
The accuracy of P-wave and S-wave matching has been improved, and high-precision matching of P-wave and S-wave profiles has been achieved, providing a reliable basis for the joint interpretation of P-wave and S-wave.
Smart Images
Figure CN120214879B_ABST
Abstract
Description
Technical Field
[0001] This invention belongs to the field of seismic exploration technology, specifically relating to a three-domain matching method for ground seismic P-waves and S-waves, electronic equipment, and media. Background Technology
[0002] As exploration targets become increasingly complex, finding oil and gas becomes increasingly difficult. P-wave and S-wave oil and gas exploration utilizes information such as the velocity, amplitude, and frequency of P-waves and S-waves during their propagation through the formation to provide more geophysical parameters, laying the foundation for high-precision oil and gas prediction. In combined P-wave and S-wave exploration, the comprehensive interpretation of P-waves and S-waves is a crucial task. Due to the inconsistent propagation paths of P-waves and S-waves within the formation, the varying degrees of absorption and attenuation by the formation, and the different degrees of anisotropy, their kinematic and dynamic characteristics differ. Therefore, matching P-waves and S-waves is a significant challenge. Only by achieving high-precision matching of P-waves and S-waves can their similarities and differences be comprehensively compared, providing a reliable basis for P-wave and S-wave interpretation. Therefore, high-precision matching of P-waves and S-waves is an urgent problem to be solved.
[0003] The existing technical solutions to the above problems are mainly coaxial similarity method, pre-stack synthetic recording method and seismic stratigraphy method. These methods all rely on obvious wave group characteristics, high signal-to-noise ratio and relatively accurate velocity of P-wave and S-wave data. However, in practical applications, the following problems exist: (1) The P-wave and S-wave profiles are quite different, and only a few geological marker layers in a few areas have obvious characteristics, making it difficult to establish accurate wave group correspondence; (2) The S-wave data has a low signal-to-noise ratio, and the coaxial characteristics of the S-wave shot-receiver offset synthetic recording are not obvious, making it impossible to establish a correspondence; (3) The compression factor obtained by dividing the S-wave velocity by the P-wave velocity varies from shallow to deep layers, and the above methods are all compression factors obtained with local wave group characteristics as reference points, which cannot represent the overall P-wave and S-wave velocity ratio and cannot achieve high-precision matching of the overall profile. Summary of the Invention
[0004] To address the aforementioned shortcomings in the prior art, the first aspect of this invention provides a three-domain matching method for ground seismic P-waves and S-waves, aiming to improve the accuracy and effectiveness of P-wave and S-wave matching.
[0005] To achieve the above objectives, the technical solution adopted by the present invention is as follows:
[0006] A three-domain matching method for ground seismic P-waves and S-waves, wherein the method first processes VSP data and uses the VSP data to establish VSP P-wave and S-wave velocity models at the same depth but different velocities.
[0007] Using VSP P-wave and S-wave velocity models, time-depth conversion is performed to transform the time-domain results of ground seismic events into the depth domain, achieving depth-domain matching of ground seismic P-waves and S-waves; based on the depth domain, time-domain matching of ground seismic P-waves and S-waves is achieved using VSP P-wave and S-wave velocity models.
[0008] Using the processed VSP data, the matching frequency band is determined by scanning the same depth frequency band of the VSP. Common-resolution filtering is then performed on the P-waves and S-waves of the ground earthquake to achieve frequency matching between the P-waves and S-waves of the ground earthquake.
[0009] As a limitation, the method includes the following steps performed sequentially:
[0010] S1 and VSP data processing: First arrival picking is performed on VSP P-waves and S-waves respectively to obtain time-depth curves of VSP P-waves and S-waves; the interference of down-going waves in VSP P-waves and S-waves is removed by wavefield separation to obtain the residual wavefields of VSP P-waves and S-waves containing up-going waves.
[0011] S2. Construct a VSP same-depth velocity model. Using the time-depth curves of VSP P-waves and S-waves, calculate the layer velocities of VSP P-waves and S-waves point by point. Adjust the layer position according to the changes in layer velocity. Establish and optimize the same-depth velocity model of VSP P-waves and S-waves based on the layer position to obtain the optimal velocity model of VSP P-waves and S-waves.
[0012] S3. Ground earthquake depth domain matching: Using the optimal velocity model of VSP P-wave and S-wave, time-depth conversion is performed on the time domain P-wave and S-wave data of ground earthquakes. By comparing the phase of earthquakes on the same depth axis, the overall matching of ground earthquake P-wave and S-wave in the depth domain is achieved.
[0013] S4. Ground earthquake time domain matching: Based on the depth domain, the optimal velocity model of VSP P-wave and S-wave is used to perform depth-time conversion on the depth domain P-wave and S-wave data of ground earthquakes. By comparing the phase of earthquakes on the same time axis, the overall matching of ground earthquake P-wave and S-wave in the time domain is achieved.
[0014] S5 and VSP are scanned at the same depth. Using depth as a scale, the remnant fields of the P-wave and S-wave of the VSP are subjected to common-resolution filtering. The correspondence between the up-going waves in the remnant fields of the P-wave and S-wave is analyzed in different scanning frequency bands. When the wave group characteristics of the up-going waves in the remnant fields of the P-wave and S-wave are basically the same, the frequency band at this time is determined as the matching frequency band.
[0015] S6. Ground earthquake frequency domain matching: Based on the matching frequency band, common-resolution filtering is performed on the P-waves and S-waves of ground earthquakes to achieve frequency matching between the P-waves and S-waves of ground earthquakes.
[0016] As a second limitation, in step S1, the Z component of the VSP longitudinal wave and the X component of the transverse wave are picked up for initial arrival respectively.
[0017] As a third limitation, the process of optimizing the optimal velocity models of VSP longitudinal and transverse waves in step S2 is as follows: adjust the layering position of the velocity models of VSP longitudinal and transverse waves until the error between the theoretical time-depth curves calculated by the velocity models of VSP longitudinal and transverse waves and the actual time-depth curves is kept within ±2ms, and the statistical law conforms to a normal distribution.
[0018] As a fourth limitation, the depth-time conversion in step S4 is to convert the P-wave and S-wave profiles in the ground seismic depth domain to the P-wave time domain or the S-wave time domain.
[0019] As a fifth limitation, the common-resolution filtering process in steps S5 and S6 is to use the same filtering parameters for bandpass filtering so that the VSP longitudinal and transverse residual wave field data are in the same frequency band.
[0020] A second aspect of the present invention discloses an electronic device including a memory and a processor, wherein the memory stores a computer program, and the processor executes the computer program to implement the steps of the above-described ground seismic P-wave and S-wave three-domain matching method.
[0021] A third aspect of the present invention discloses a computer-readable storage medium having a computer program stored thereon, wherein the processor executes the computer program to implement the steps of the above-described ground seismic P-wave and S-wave three-domain matching method.
[0022] By adopting the above-described technical solution, the beneficial effects achieved by this invention compared to the prior art are as follows:
[0023] (1) This invention establishes a complete matching process and utilizes the high-precision speed and high-resolution wavefield information of VSP to build a bridge between P-wave data and S-wave data, overcoming the dependence of existing technologies such as the phase axis similarity method, pre-stack synthetic recording method and seismic stratigraphy method on the wave group characteristics and signal-to-noise ratio of P-wave and S-wave data.
[0024] (2) This invention develops the local part-time window matching of the previous method into overall multi-domain matching, which greatly improves the accuracy and effect of P-wave and S-wave matching and lays the foundation for the joint interpretation of P-wave and S-wave.
[0025] In summary, this invention greatly improves the accuracy and effect of P-wave and S-wave matching, achieving high-precision overall matching of P-wave and S-wave profiles. Attached Figure Description
[0026] The present invention will now be described in further detail with reference to the accompanying drawings and specific embodiments.
[0027] Figure 1 This is a schematic diagram of the method flow of Embodiment 1 of the present invention;
[0028] Figure 2 This is a time-depth curve diagram of the VSP longitudinal wave and transverse wave in Embodiment 1 of the present invention;
[0029] Figure 3 This is a cross-sectional view of the VSP longitudinal and transverse wave residual wave fields in Embodiment 1 of the present invention;
[0030] Figure 4 This is a diagram of the optimal velocity model for VSP longitudinal and transverse waves in Embodiment 1 of the present invention;
[0031] Figure 5 This is the time-domain profile of ground seismic P-waves and S-waves in Embodiment 1 of the present invention;
[0032] Figure 6 This is a depth domain profile of ground seismic P-waves and S-waves in Embodiment 1 of the present invention;
[0033] Figure 7 This is the time-domain profile of the P-wave and S-wave of a ground earthquake in Embodiment 1 of the present invention;
[0034] Figure 8 This is the shear wave time domain profile of ground seismic P-waves and S-waves in Embodiment 1 of the present invention;
[0035] Figure 9 This is a comparison diagram of the VSP longitudinal wave and transverse wave residual wave fields containing an upward wave in Embodiment 1 of the present invention;
[0036] Figure 10 This is a comparison diagram of the VSP longitudinal wave and transverse wave residual fields containing the ascending wave after frequency domain matching in Embodiment 1 of the present invention.
[0037] Figure 11 This is a cross-sectional view of the ground seismic P-wave and S-wave after frequency domain matching in Embodiment 1 of the present invention;
[0038] Figure 12 This is the result of depth domain stratigraphic interpretation of ground seismic P-waves and S-waves in Embodiment 1 of the present invention;
[0039] Figure 13 This is the result of interpreting the target layer reservoir parameters in the depth domain of ground seismic P-waves and S-waves in Embodiment 1 of the present invention. Detailed Implementation
[0040] To better explain and facilitate understanding of the present invention, the preferred embodiments of the present invention will be described in detail below with reference to the accompanying drawings and specific implementation methods.
[0041] Example 1: Ground Seismic P-wave and S-wave Three-Domain Matching Method
[0042] This embodiment provides a three-domain matching method for ground seismic P-waves and S-waves, such as... Figure 1 The diagram shows the following steps performed sequentially:
[0043] S1 and VSP (Vertical Seismic Profile) data processing: First arrival picking of the Z component of VSP P-wave and the X component of VSP S-wave are performed to obtain the time-depth curves of VSP P-wave and S-wave. The interference of down-going waves in VSP P-wave and S-wave is removed by wavefield separation to obtain the residual wavefield of VSP P-wave and S-wave containing up-going waves.
[0044] like Figure 2 As shown in the figure, the curve on the left represents the P-wave time-depth curve, and the curve on the right represents the S-wave time-depth curve. It can be seen from the figure that when the P-wave and S-wave correspond to the same depth, the time corresponding to the S-wave is greater than that of the P-wave. Figure 3 (a) is a wave profile of the VSP longitudinal wave residual field. Figure 3 (b) is a VSP shear wave residual wave profile. The residual wave field can more realistically represent the reflection wave characteristics of seismic waves at various wave impedance interfaces. In order to maintain the original characteristics of the up-going wave, it is not processed too much.
[0045] S2. Construct a VSP same-depth velocity model. Using the time-depth curves of VSP P-waves and S-waves, calculate the point-by-point layer velocities of VSP P-waves and S-waves respectively. Based on the changes in the layer velocities of VSP P-waves and S-waves, establish and optimize the same-depth velocity model of VSP P-waves and S-waves to obtain the optimal velocity model of VSP P-waves and S-waves.
[0046] Specifically, the optimal velocity models for the VSP P-wave and S-wave are obtained when the error between the theoretical time-depth curves calculated by the VSP P-wave and S-wave velocity models and the actual time-depth curves obtained from the initial pick-up in step S1 is maintained within ±2ms and the statistical regularity conforms to a normal distribution. Figure 4 (a) is the optimal velocity model diagram of VSP P-wave in Embodiment 1 of the present invention, wherein ① is the velocity model after P-wave square wave conversion, ② is the velocity of VSP P-wave layer, ③ is the error statistical analysis curve, and ④ is used to check the consistency of the time-depth curve, wherein the error between the theoretical time-depth curve calculated by the VSP P-wave velocity model and the actual time-depth curve is less than ±0.74ms. Figure 4 (b) is the optimal velocity model diagram of VSP shear wave in Embodiment 1 of the present invention, wherein the error between the theoretical time-depth curve calculated by the VSP longitudinal wave velocity model and the actual time-depth curve is less than ±1.69ms.
[0047] S3, ground seismic depth domain matching, for example Figure 5 (a) shows the time-domain profile of ground seismic P-waves and Figure 5(b) shows the time-domain profile of the ground seismic shear waves. The two differ significantly; except for the standard layer indicated by ⑤, the other layers exhibit varying degrees of difference, making direct comparison and analysis impossible using the traditional coaxial similarity method. To achieve joint interpretation of P-waves and S-waves in the same domain, the optimal velocity model for VSP P-waves and S-waves is used to perform time-depth conversion on the time-domain VSP P-wave and S-wave data of the ground seismic event, resulting in the following... Figure 6 (a) Depth-domain profile of surface seismic P-waves and Figure 6 (b) The depth domain profile of ground seismic shear waves. The P-wave and S-wave data converted to the depth domain have a common depth range from shallow to deep and the depths are corresponding. By comparing the seismic phases along the same depth axis, the overall matching of VSP P-waves and S-waves in the depth domain is achieved.
[0048] S4. Ground earthquake time domain matching: Based on the depth domain, the optimal velocity model of VSP P-waves and S-waves is used to perform depth-time conversion on the depth domain P-wave and S-wave data of ground earthquakes. The P-wave and S-wave data converted to the time domain have a common time range from shallow to deep and the time corresponds. By comparing the earthquake phases on the same time axis, the overall matching of ground earthquake P-waves and S-waves in the time domain is achieved.
[0049] Specifically, depth-time conversion is performed on the depth-domain P-wave and S-wave data of ground earthquakes, that is, the P-wave and S-wave profiles in the depth domain of ground earthquakes are converted to the P-wave time domain or the S-wave time domain to obtain, as shown below. Figure 7 (a) shows the time-domain profile of the P-wave of a ground earthquake. Figure 7 (b) shows the P-wave time-domain profile of the ground seismic shear wave; or obtain as shown in the figure. Figure 8 (a) shows the time-domain profile of the P-wave of a ground earthquake and the S-wave profile. Figure 8 (b) shows the time-domain profile of a ground seismic shear wave. (Comparison) Figure 7 (a) and Figure 7 (b) or comparison Figure 8 (a) and Figure 8 (b) The longitudinal and transverse wave profiles after co-domain processing are basically consistent in the main marker layers, but there are differences at individual locations due to frequency influence, which affects the overall understanding of the profile and requires frequency domain matching.
[0050] S5 and VSP same-depth frequency band scanning, using depth as a scale, performs co-resolution filtering on the residual wave fields of ground seismic P-waves and S-waves. That is, by using the same filtering parameters for bandpass filtering, the residual wave field data of VSP P-waves and S-waves are placed in the same frequency band. Then, the correspondence between the ascending waves in the residual wave fields of ground seismic P-waves and S-waves is analyzed in different scanning frequency bands. When the two show similarity at the main lithological interfaces, the frequency band at this time is determined as the matching frequency band.
[0051] Specifically, Figure 9 The diagram shows a comparison of the remnant wave fields of the VSP P-wave and S-wave containing the ascending wave. The left side of the diagram is the VSP S-wave remnant wave field profile, and the right side is the VSP P-wave remnant wave field profile. In the diagram, the wave group characteristics of the P-wave and S-wave ascending wave fields are mostly good. Only at positions T1 and T11 are the P-wave and S-wave waves significantly different. In the P-wave profile, the ascending reflected wave energy at position T1 is stronger than that at position T11, while in the S-wave profile, the ascending reflected wave energy at position T1 is weaker than that at position T11. Figure 10 The figure shows a comparison of the VSP longitudinal wave and transverse wave residual fields containing the up-going wave after frequency domain matching. The left side of the figure is the VSP transverse wave residual field profile, and the right side is the VSP longitudinal wave residual field profile. When the low-pass filter is applied at (15, 20) Hz, the wave group characteristics of the longitudinal wave and transverse wave up-going wave fields are basically the same. The (15, 20) Hz frequency band is determined as the matching frequency band.
[0052] S6. Ground seismic frequency domain matching: Based on the matching frequency band, common-resolution filtering is performed on the P-waves and S-waves of the ground seismic event. The processed result is as follows: Figure 11 (a) Surface seismic P-wave frequency domain matching profile and Figure 11 (b) Profile of ground seismic shear wave after frequency domain matching; the profile characteristics of the two are basically the same after processing, realizing frequency matching of ground seismic P-wave and S-wave.
[0053] Through steps S1-S6, the matching of ground seismic P-waves and S-waves was completed. Based on this, this embodiment completed the P-wave and S-wave layer calibration and interpretation work and the elastic parameter prediction of the target segment on the depth domain profile. Figure 12 (a) shows the results of depth domain layer interpretation of ground seismic P-waves, where ⑥ is the P-wave interpretation fault; Figure 12 (b) shows the depth domain layer interpretation results of ground seismic shear waves, and (⑦) shows the faults interpreted by shear waves. Figure 13 (a) represents the ratio of P-wave to S-wave velocity in the target layer. Figure 13 (b) is the Poisson's ratio of the target layer. Figure 13 (c) represents the shear modulus of the target segment. Figure 13 (d) represents the Young's modulus of the target layer. Based on the seismic elastic parameters obtained above, the lithological variation characteristics of the target layer are further studied.
[0054] Example 2: Electronic device and storage medium for three-domain matching of ground seismic P-waves and S-waves
[0055] The electronic device in this embodiment is a computer device, including a memory and a processor. The memory stores a computer program, and when the processor executes the computer program, it can implement the steps of the ground seismic P-wave and S-wave three-domain matching method in Embodiment 1.
[0056] A computer-readable storage medium stores a computer program thereon, which, when executed by a processor, implements the steps of the ground seismic P-wave and S-wave three-domain matching method in Embodiment 1. The computer program includes computer program code, which may be in the form of source code, object code, executable file, or some intermediate form. The computer-readable medium includes: any entity or device capable of carrying the computer program code, recording media, USB flash drive, portable hard drive, magnetic disk, optical disk, computer memory, read-only memory (ROM), random access memory (RAM), electrical carrier signals, telecommunication signals, and software distribution media, etc.
Claims
1. A three-domain matching method for ground seismic P-waves and S-waves, characterized in that, The method includes the following steps performed sequentially: S1 and VSP data processing: First arrival picking is performed on VSP P-waves and S-waves respectively to obtain time-depth curves of VSP P-waves and S-waves; the interference of down-going waves in VSP P-waves and S-waves is removed by wavefield separation to obtain the residual wavefields of VSP P-waves and S-waves containing up-going waves. S2. Construct a VSP same-depth velocity model. Using the time-depth curves of VSP P-waves and S-waves, calculate the layer velocities of VSP P-waves and S-waves point by point. Adjust the layer position according to the changes in layer velocity. Establish and optimize the same-depth velocity model of VSP P-waves and S-waves based on the layer position to obtain the optimal velocity model of VSP P-waves and S-waves. S3. Ground earthquake depth domain matching: Using the optimal velocity model of VSP P-wave and S-wave, time-depth conversion is performed on the time domain P-wave and S-wave data of ground earthquakes. By comparing the phase of earthquakes on the same depth axis, the overall matching of ground earthquake P-wave and S-wave in the depth domain is achieved. S4. Ground earthquake time domain matching: Based on the depth domain, the optimal velocity model of VSP P-wave and S-wave is used to perform depth-time conversion on the depth domain P-wave and S-wave data of ground earthquakes. By comparing the phase of earthquakes on the same time axis, the overall matching of ground earthquake P-wave and S-wave in the time domain is achieved. S5 and VSP are scanned at the same depth. Using depth as a scale, the remnant fields of the P-wave and S-wave of the VSP are subjected to common-resolution filtering. The correspondence between the up-going waves in the remnant fields of the P-wave and S-wave is analyzed in different scanning frequency bands. When the wave group characteristics of the up-going waves in the remnant fields of the P-wave and S-wave are basically the same, the frequency band at this time is determined as the matching frequency band. S6. Ground earthquake frequency domain matching: Based on the matching frequency band, common-resolution filtering is performed on the P-waves and S-waves of ground earthquakes to achieve frequency matching between the P-waves and S-waves of ground earthquakes.
2. The ground seismic P-wave and S-wave three-domain matching method according to claim 1, characterized in that, In step S1, the Z component of the longitudinal wave and the X component of the transverse wave of the VSP are picked up from their initial arrival.
3. The ground seismic P-wave and S-wave three-domain matching method according to claim 1, characterized in that, The process of optimizing the optimal velocity models of VSP longitudinal and transverse waves in step S2 is as follows: adjust the layering position of the velocity models of VSP longitudinal and transverse waves until the error between the theoretical time depth curves calculated by the velocity models of VSP longitudinal and transverse waves and the actual time depth curves obtained from the beginning of step S1 is kept within ±2ms, and the statistical law conforms to the normal distribution.
4. The ground seismic P-wave and S-wave three-domain matching method according to claim 1, characterized in that, In step S4, the depth-time conversion involves converting the P-wave and S-wave profiles from the ground seismic depth domain to either the P-wave time domain or the S-wave time domain.
5. The ground seismic P-wave and S-wave three-domain matching method according to claim 1, characterized in that, The common-resolution filtering process in steps S5 and S6 involves bandpass filtering with the same filtering parameters to ensure that the VSP longitudinal and transverse residual wavefield data are within the same frequency band.
6. An electronic device comprising a memory and a processor, wherein the memory stores a computer program, characterized in that, When the processor executes the computer program, it implements the steps of the method described in any one of claims 1-5.
7. A computer-readable storage medium having a computer program stored thereon, characterized in that, When the computer program is executed by the processor, it implements the steps of the method described in any one of claims 1-5.