Angle domain omni-directional speed modeling method and device for fracture and electronic equipment

Abstract

The invention discloses an angle domain omnibearing speed modeling method and device for fracture and electronic equipment, and the method comprises the steps: carrying out angle domain migration imaging through employing a CMP gather and a depth domain speed model updated through a conventional method, and obtaining an angle domain reflection angle gather and an angle domain inclination angle gather; carrying out superposition imaging by using the angle domain inclination angle gather to obtain an imaging profile, and interpreting a horizon and extracting a structure attribute by using the imaging profile; and on the basis of the extracted structural attributes and horizon constraints, carrying out automatic residual delay pickup on an angle domain reflection angle gather to carry out omni-directional angle domain tomographic inversion so as to obtain a new velocity model. According to the method, a more accurate speed model can be inverted, and the imaging precision at the fault zone is improved.

Description

Technical Field

[0001] The present invention belongs to the field of geophysical exploration seismic data processing, and more specifically, relates to an angle domain omnidirectional velocity modeling method, device and electronic equipment for faults. Background Art

[0002] The velocity problem is the core issue of exploration seismology. The degree of understanding of the velocity field basically represents the degree of understanding of the underground geological conditions of an exploration area. On the one hand, the seismic wave velocity of the underground medium is closely related to the physical properties of the rock, which can reflect the rock type and the condition of the fluid (oil or natural gas) contained therein; on the other hand, the seismic wave velocity of the underground medium directly determines the results of seismic wave migration imaging, which in turn affects geologists' grasp of the underground geological structure of the entire exploration area. For any migration method, the correctness of the velocity model directly determines the key factor in the quality of structural imaging. Migration velocity modeling is the core of seismic imaging.

[0003] The establishment of the velocity model in the depth domain generally includes five processes: structural interpretation, initial velocity modeling, target line migration imaging, model optimization iteration and update, and prestack depth migration volume migration. Among them, the optimization iteration of the model is the key and core step. At present, the CIP gathers of the target line generated by the Kirchhoff prestack depth migration method or the OVG gathers generated by the OVT domain migration are generally used to iteratively update the velocity model. However, for carbonate fault-controlled fracture-cavity reservoirs, the heterogeneity in the fault zone is strong. In the actual processing process, the iterative velocity model is first updated by conventional grid tomography. Due to the limitation of the offset distance gather without azimuth information, the lateral velocity anomaly of the fault zone cannot be inverted. Then the OVT domain velocity modeling is continued to be used to further improve the accuracy of the fault zone model. However, since the azimuth of OVT is not the real angle underground, the beads are not convergent enough in the fault zone with strong lateral heterogeneity, and the imaging inside the fault zone is not clear enough. Summary of the invention

[0004] The purpose of the present invention is to provide a method, device and electronic equipment for omnidirectional velocity modeling in the angle domain of a fault, so as to achieve a more accurate velocity model and improve the imaging accuracy at the fault zone.

[0005] To achieve the above objectives, in a first aspect, the present invention proposes an angle domain omnidirectional velocity modeling method for fractures, comprising:

[0006] S1: Angle domain migration imaging is performed using CMP gathers and a depth domain velocity model updated by a conventional method to obtain an angle domain five-dimensional gather, wherein the angle domain five-dimensional gather includes an angle domain reflection angle gather and an angle domain dip angle gather;

[0007] S2: using the angle domain dip gather to perform stacking imaging to obtain an imaging section, and using the imaging section to interpret the horizon and extract structural attributes;

[0008] S3: Based on the extracted structural attributes and layer constraints, full-range angle domain tomographic inversion is performed by automatically picking up the residual delay of the angle domain reflection angle gathers to obtain a new velocity model.

[0009] Optionally, the method further comprises:

[0010] S4: Determine whether the new velocity model meets the quality requirement. If so, output the new velocity model as the final velocity model. Otherwise, use the new velocity model as the initial velocity model and return to S1.

[0011] Optionally, the determining whether the new velocity model meets the quality requirement includes:

[0012] Performing depth migration imaging using the new velocity model;

[0013] Based on the migration imaging results, it is determined whether the vertical residual delay tends to be close to 0, whether the gather event axis is flattened, whether the profile fracture is clear, and whether the beads are focused. If so, the new velocity model meets the quality requirements.

[0014] Optionally, the CMP gather is a CMP gather that has undergone preliminary fine processing.

[0015] Optionally, the structural attributes include dip, azimuth and continuity.

[0016] In a second aspect, the present invention provides an electronic device, the electronic device comprising:

[0017] at least one processor; and,

[0018] a memory communicatively connected to the at least one processor; wherein,

[0019] The memory stores instructions that can be executed by the at least one processor, and the instructions are executed by the at least one processor so that the at least one processor can execute any method for angular domain all-round velocity modeling for fracture as described in the first aspect.

[0020] In a third aspect, the present invention proposes a non-transitory computer-readable storage medium storing computer instructions for causing a computer to execute any of the angle domain all-round velocity modeling methods for fractures described in the first aspect.

[0021] In a fourth aspect, the present invention provides an angular domain omnidirectional velocity modeling device for fractures, comprising:

[0022] A reflection angle gather calculation module is used to perform angle domain migration imaging using the CMP gather and the initial velocity model to obtain an angle domain five-dimensional gather, wherein the angle domain five-dimensional gather includes an angle domain reflection angle gather and an angle domain dip angle gather;

[0023] A structural attribute extraction module, used for obtaining an imaging section by stacking the angle domain dip gathers, interpreting the horizon and extracting structural attributes by using the imaging section;

[0024] The velocity model inversion module performs omnidirectional angle domain tomographic inversion based on the extracted structural attributes and layer constraints by automatically picking up the residual delay of the angle domain reflection angle gathers to obtain a new velocity model.

[0025] Optionally, the device also includes a quality judgment module for judging whether the new velocity model meets the quality requirements. If so, the new velocity model is output as the final velocity model; otherwise, the new velocity model is used as the initial velocity model and the angle domain reflection angle gather is recalculated through the reflection angle gather calculation module.

[0026] Optionally, the determining whether the new velocity model meets the quality requirement includes:

[0027] Performing depth migration imaging using the new velocity model;

[0028] Based on the migration imaging results, it is determined whether the vertical residual delay tends to be close to 0, whether the gather event axis is flattened, whether the profile fracture is clear, and whether the beads are focused. If so, the new velocity model meets the quality requirements.

[0029] The beneficial effects of the present invention are:

[0030] The present invention picks up the residual delay based on the five-dimensional omnidirectional reflection angle gather, and can distinguish the residual delays on both sides of the lateral velocity mutation, and invert more accurate results. In particular, in the target layer with low signal-to-noise ratio and the fracture of the fault-controlled fracture-cavity reservoir, due to the lateral heterogeneity, the velocity changes drastically in the lateral direction. Based on the residual delay picked up by the omnidirectional reflection angle gather, a more accurate velocity model is inverted, the imaging effect is significantly improved, and a more reliable and more amplitude-preserving structural imaging is obtained.

[0031] The system of the present invention has other characteristics and advantages, which will be apparent from the drawings incorporated herein and the following detailed description, or will be described in detail in the drawings incorporated herein and the following detailed description, which together serve to explain the specific principles of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] The above and other objects, features and advantages of the present invention will become more apparent through a more detailed description of exemplary embodiments of the present invention in conjunction with the accompanying drawings, in which like reference numerals generally represent like components.

[0033] Figure 1 A step diagram of a method for omnidirectional velocity modeling in an angle domain for fracture according to the present invention is shown.

[0034] Figure 2 A flow chart of a method for omnidirectional velocity modeling in the angle domain for fractures according to an embodiment of the present invention is shown.

[0035] Figure 3 The quality control diagram of vertical residual delay contrast before and after full-range angle domain tomographic inversion is shown.

[0036] Figure 4 The quality control diagram of the gather comparison before and after omni-directional angle domain tomographic inversion is shown.

[0037] Figure 5 The quality control diagram of the velocity model comparison before and after full-range angle domain tomographic inversion is shown.

[0038] Figure 6 The quality control diagram of the fracture contrast of the migrated profile before and after the full range of angle domain tomographic inversion is shown.

[0039] Figure 7 The quality control diagram of the beaded focus contrast of the migrated profile before and after the full range of angle domain tomographic inversion is shown. DETAILED DESCRIPTION

[0040] Due to the defects of the conventional offset gather updating velocity model and the OVT domain gather wide azimuth velocity model iteration, both cannot accurately depict the problem of lateral velocity anomalies in the fault zone. Therefore, the present invention proposes an angle domain omnidirectional velocity modeling method for the fault, which uses the five-dimensional reflection angle gathers offset in the angle domain, the gathers reflecting the actual dip and azimuth angles of the underground, and the omnidirectional angle domain tomography constrained by the layer position. For the fault-controlled fracture-cavity reservoir with strong lateral heterogeneity, the residual delay of the lateral velocity mutation can be distinguished, and a more accurate velocity model can be inverted to improve the imaging accuracy at the fault zone. The present invention has a good application prospect in velocity model accuracy and high-quality amplitude-preserving imaging.

[0041] The present invention will be described in more detail below with reference to the accompanying drawings. Although preferred embodiments of the present invention are shown in the accompanying drawings, it should be understood that the present invention can be implemented in various forms and should not be limited by the embodiments set forth herein. On the contrary, these embodiments are provided to make the present invention more thorough and complete, and to fully convey the scope of the present invention to those skilled in the art.

[0042] Example 1

[0043] like Figure 1 As shown, this embodiment provides an angle domain omnidirectional velocity modeling method for fractures, including:

[0044] S1: Angle domain migration imaging is performed using CMP gathers and a depth domain velocity model updated by a conventional method to obtain an angle domain five-dimensional gather, wherein the angle domain five-dimensional gather includes: an angle domain reflection angle gather and an angle domain dip angle gather;

[0045] Preferably, the CMP gather is a CMP gather that has undergone preliminary fine processing.

[0046] The angle domain reflection angle gather obtained in this step has the characteristics of high signal-to-noise ratio and continuous reflection angle and azimuth information.

[0047] S2: Use the angle domain dip gathers to stack and image to obtain imaging sections, and use the imaging sections to interpret the horizons and extract structural attributes;

[0048] Among them, structural attributes include dip, azimuth and continuity.

[0049] S3: Based on the extracted structural attributes and layer constraints, the angle domain reflection angle gathers are automatically picked up to perform all-round angle domain tomographic inversion and obtain a new velocity model.

[0050] This step is aimed at fault-controlled fracture-cavity reservoirs with strong lateral heterogeneity, and can distinguish the residual delay of lateral velocity mutations to invert a more accurate velocity model. At the same time, the omnidirectional angle domain tomographic inversion based on the reflection angle gather can improve the accuracy of the velocity model, especially in the target layer with low signal-to-noise ratio and the fracture with strong lateral heterogeneity.

[0051] S4: Determine whether the new velocity model meets the quality requirements. If so, output the new velocity model as the final velocity model. Otherwise, use the new velocity model as the initial velocity model and return to S1.

[0052] In this step, judging whether the new velocity model meets the quality requirements includes:

[0053] Depth migration imaging using new velocity models;

[0054] Based on the migration imaging results, it is determined whether the vertical residual delay tends to be close to 0, whether the gather event axis is flattened, whether the profile fracture is clear, and whether the beads are focused. If so, the new velocity model meets the quality requirements.

[0055] Example 2

[0056] This embodiment provides a method for modeling the omnidirectional velocity in the angle domain of a fracture. Figure 2 As shown, the specific process includes:

[0057] 1. Use the CMP gathers that have been finely processed in the early stage and the updated depth domain velocity model to perform angle domain migration imaging to obtain five-dimensional gathers, including: angle domain reflection angle gathers and angle domain dip angle gathers. The reflection angle gathers have the characteristics of high signal-to-noise ratio and continuous reflection angle and azimuth information.

[0058] 2. Use angle domain dip gathers for stacking imaging to obtain imaging sections with high signal-to-noise ratio to interpret the layers and extract structural properties (dip, azimuth, continuity).

[0059] 3. Based on structural attributes and layer constraints, the angle domain reflection angle gathers are automatically picked up for residual delay to perform all-round angle domain tomographic inversion. For fault-controlled fracture-cavity reservoirs with strong lateral heterogeneity, the residual delay of lateral velocity mutations can be distinguished to invert a more accurate velocity model ( Figure 5 ). Based on the full-range angle domain tomographic inversion of reflection angle gathers, the accuracy of velocity model is improved, especially in the target layer with low signal-to-noise ratio and the fault with strong lateral heterogeneity.

[0060] 4. Use the new velocity model of omnidirectional angle domain tomographic inversion to perform depth migration, and judge whether: ① the vertical residual delay tends to be close to 0 ( Figure 3 ) ② Whether the gather event axis is flattened ( Figure 4 ), ③ Whether the cross-section fracture is clear and whether the beads are focused ( Figure 6 , Figure 7 ) is used to qualitatively and quantitatively evaluate the quality control system of the velocity model.

[0061] pass Figures 3 to 6 It can be seen that the method of the present invention is used to iteratively update the omnidirectional tomographic velocity model of a certain three-dimensional seismic data in the angle domain, which can effectively improve the velocity model accuracy and imaging quality of the fracture with strong heterogeneity in the low signal-to-noise ratio area.

[0062] The present invention picks up the residual delay based on the five-dimensional omnidirectional reflection angle gather, and can distinguish the residual delays on both sides of the lateral velocity mutation, and invert more accurate results. In particular, in the target layer section with low signal-to-noise ratio and the fault-controlled fracture-cavity reservoir fracture, due to the lateral heterogeneity, the velocity changes drastically in the lateral direction. Based on the residual delay picked up by the omnidirectional reflection angle gather, a more accurate velocity model is inverted, the imaging effect is significantly improved, and a more reliable and more amplitude-preserving structural imaging is obtained. The invention has a good application prospect in terms of high velocity model inversion accuracy and accurate imaging.

[0063] Example 3

[0064] This embodiment provides an angular domain omnidirectional velocity modeling device for fractures, comprising:

[0065] A reflection angle gather calculation module is used to perform angle domain migration imaging using the CMP gather and the initial velocity model to obtain a five-dimensional gather, wherein the angle domain five-dimensional gather includes: an angle domain reflection angle gather and an angle domain dip angle gather;

[0066] A structural attribute extraction module, used for obtaining an imaging section by stacking the angle domain dip gathers, interpreting the horizon and extracting structural attributes by using the imaging section;

[0067] The velocity model inversion module performs omnidirectional angle domain tomographic inversion based on the extracted structural attributes and layer constraints by automatically picking up the residual delay of the angle domain reflection angle gathers to obtain a new velocity model.

[0068] In this embodiment, the device also includes a quality judgment module for judging whether the new velocity model meets the quality requirements. If so, the new velocity model is output as the final velocity model; otherwise, the new velocity model is used as the initial velocity model and the angle domain reflection angle gather is recalculated through the reflection angle gather calculation module.

[0069] Wherein, judging whether the new velocity model meets the quality requirements includes:

[0070] Performing depth migration imaging using the new velocity model;

[0071] Based on the migration imaging results, it is determined whether the vertical residual delay tends to be close to 0, whether the gather event axis is flattened, whether the profile fracture is clear, and whether the beads are focused. If so, the new velocity model meets the quality requirements.

[0072] Example 4

[0073] This embodiment provides an electronic device, the electronic device comprising:

[0074] at least one processor; and,

[0075] a memory communicatively connected to the at least one processor; wherein,

[0076] The memory stores instructions that can be executed by the at least one processor, and the instructions are executed by the at least one processor so that the at least one processor can execute the angle domain omnidirectional velocity modeling method for fracture described in the above embodiments 1 and 2.

[0077] The electronic device according to an embodiment of the present disclosure includes a memory and a processor, and the memory is used to store non-temporary computer-readable instructions. Specifically, the memory may include one or more computer program products, and the computer program product may include various forms of computer-readable storage media, such as volatile memory and / or non-volatile memory. The volatile memory may, for example, include a random access memory (RAM) and / or a cache memory (cache), etc. The non-volatile memory may, for example, include a read-only memory (ROM), a hard disk, a flash memory, etc.

[0078] The processor may be a central processing unit (CPU) or other forms of processing units having data processing capabilities and / or instruction execution capabilities, and may control other components in the electronic device to perform desired functions. In one embodiment of the present disclosure, the processor is used to run the computer-readable instructions stored in the memory.

[0079] Those skilled in the art should be able to understand that in order to solve the technical problem of how to obtain a good user experience, the present embodiment may also include well-known structures such as a communication bus and an interface, and these well-known structures should also be included in the protection scope of the present disclosure.

[0080] For detailed description of this embodiment, reference may be made to the corresponding descriptions in the aforementioned embodiments, which will not be repeated here.

[0081] Example 5

[0082] This embodiment provides a non-transitory computer-readable storage medium, which stores computer instructions. The computer instructions are used to enable a computer to execute the angle domain omnidirectional velocity modeling method for fracture described in the above embodiments 1 and 2.

[0083] According to the computer-readable storage medium of the embodiment of the present disclosure, non-transitory computer-readable instructions are stored thereon. When the non-transitory computer-readable instructions are executed by a processor, all or part of the steps of the above-mentioned methods of each embodiment of the present disclosure are executed.

[0084] The above-mentioned computer-readable storage media include, but are not limited to: optical storage media (e.g., CD-ROM and DVD), magneto-optical storage media (e.g., MO), magnetic storage media (e.g., magnetic tape or mobile hard disk), media with built-in rewritable non-volatile memory (e.g., memory card) and media with built-in ROM (e.g., ROM box).

[0085] The embodiments of the present invention have been described above, and the above description is exemplary, not exhaustive, and is not limited to the disclosed embodiments. Many modifications and changes will be apparent to those skilled in the art without departing from the scope and spirit of the described embodiments.

Claims

1. A method for modeling all-round velocity in the angle domain for fractures, It is characterized in that include: S1: Angle domain migration imaging is performed using CMP gathers and a depth domain velocity model updated by a conventional method to obtain an angle domain five-dimensional gather, wherein the angle domain five-dimensional gather includes an angle domain reflection angle gather and an angle domain dip angle gather; S2: using the angle domain dip gather to perform stacking imaging to obtain an imaging section, and using the imaging section to interpret the horizon and extract structural attributes; S3: Based on the extracted structural attributes and layer constraints, full-range angle domain tomographic inversion is performed by automatically picking up the residual delay of the angle domain reflection angle gathers to obtain a new velocity model.

2. The angle domain omnidirectional velocity modeling method for fracture according to claim 1, It is characterized in that The method further comprises: S4: Determine whether the new velocity model meets the quality requirement. If so, output the new velocity model as the final velocity model. Otherwise, use the new velocity model as the initial velocity model and return to S1.

3. The angle domain omnidirectional velocity modeling method for fracture according to claim 2, It is characterized in that Determining whether the new velocity model meets the quality requirements includes: Performing depth migration imaging using the new velocity model; Based on the migration imaging results, it is determined whether the vertical residual delay tends to be close to 0, whether the gather event axis is flattened, whether the profile fracture is clear, and whether the beads are focused. If so, the new velocity model meets the quality requirements.

4. The angle domain omnidirectional velocity modeling method for fracture according to claim 1, It is characterized in that The CMP gathers are CMP gathers that have undergone preliminary fine processing.

5. The angle domain omnidirectional velocity modeling method for fracture according to claim 1, It is characterized in that The structural attributes include dip, azimuth and continuity volume.

6. An electronic device, It is characterized in that The electronic device comprises: at least one processor; and, a memory communicatively connected to the at least one processor; wherein, The memory stores instructions executable by the at least one processor, and the instructions are executed by the at least one processor so that the at least one processor can execute the angle domain omnidirectional velocity modeling method for fracture as described in any one of claims 1-5.

7. A non-transitory computer-readable storage medium, It is characterized in that The non-transitory computer-readable storage medium stores computer instructions, which are used to enable a computer to execute the angle domain omnidirectional velocity modeling method for fracture as described in any one of claims 1-5.

8. A device for modeling all-round velocity in the angle domain for fractures, It is characterized in that include: A reflection angle gather calculation module is used to perform angle domain migration imaging using the CMP gather and the depth domain velocity model updated by the conventional method to obtain an angle domain five-dimensional gather, wherein the angle domain five-dimensional gather includes an angle domain reflection angle gather and an angle domain dip angle gather; A structural attribute extraction module, used for obtaining an imaging section by stacking the angle domain dip gathers, interpreting the horizon and extracting structural attributes by using the imaging section; The velocity model inversion module performs omnidirectional angle domain tomographic inversion based on the extracted structural attributes and layer constraints by automatically picking up the residual delay of the angle domain reflection angle gathers to obtain a new velocity model.

9. The device for angular domain omnidirectional velocity modeling for fracture according to claim 8, It is characterized in that The device also includes a quality judgment module for judging whether the new velocity model meets the quality requirements. If so, the new velocity model is output as the final velocity model; otherwise, the new velocity model is used as the initial velocity model and the angle domain reflection angle gather is recalculated through the reflection angle gather calculation module.

10. The device for angular domain omnidirectional velocity modeling for fracture according to claim 9, It is characterized in that Determining whether the new velocity model meets the quality requirements includes: Performing depth migration imaging using the new velocity model; Based on the migration imaging results, it is determined whether the vertical residual delay tends to be close to 0, whether the gather event axis is flattened, whether the profile fracture is clear, and whether the beads are focused. If so, the new velocity model meets the quality requirements.

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