A three-dimensional seismic forward modeling method based on river sedimentary facies constraint
By using a three-dimensional seismic forward modeling method based on river sedimentary facies constraints, the problem of the inability of existing technologies to reflect the three-dimensional spatiotemporal changes of reservoirs has been solved. This method achieves an objective reflection and flexible adjustment of the seismic response characteristics of reservoir structure and sedimentary system, and simplifies the seismic processing procedure.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- CHINA PETROCHEMICAL CORP
- Filing Date
- 2023-10-08
- Publication Date
- 2026-06-12
AI Technical Summary
Existing three-dimensional reservoir sand body seismic forward modeling methods are difficult to effectively reflect the three-dimensional spatiotemporal changes of reservoirs, especially the reflection characteristics of reservoirs with thin sand body thickness, poor lateral continuity, and uneven distribution of physical properties. Furthermore, the simulation results are greatly affected by the seismic processing steps.
A three-dimensional seismic forward modeling method based on river sedimentary facies constraints was adopted. Well-connected profiles were created by well location distribution, sub-layers were divided and sedimentary facies modeling was performed to generate a three-dimensional lithofacies model. Velocity modeling was performed by combining sonic logging curves, and seismic forward modeling was performed using the vertical incidence convolution operation method.
It can objectively and effectively reflect the seismic response characteristics of different sedimentary systems and reservoir structures, flexibly adjust seismic wavelet parameters, study the seismic signal variation law of the spatiotemporal evolution of sedimentary systems and the changes in reservoir lithology and physical properties, and simplify the seismic acquisition and processing process.
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Figure CN117492086B_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the field of earthquake simulation technology, and in particular to a three-dimensional forward modeling method for earthquakes based on river sedimentary facies constraints. Background Technology
[0002] Different geological bodies exhibit varying seismic reflection characteristics due to differences in their rock assemblage, internal structure, lithology, physical properties, and hydrocarbon content. These characteristics include reflection morphology, internal structure, reflection frequency, amplitude, and other seismic parameters. The complexity of underground geology and the seismic wave propagation process, coupled with interference from various waves, leads to multiple interpretations of reflection phenomena in seismic profiles, significantly increasing the difficulty of seismic data interpretation.
[0003] Due to the complexity of three-dimensional reservoir sand body modeling, studies on the seismic reflection characteristics of reservoir sand bodies are usually conducted on two-dimensional profiles. However, two-dimensional profiles are insufficient to reflect the seismic signal variations caused by the three-dimensional spatiotemporal changes of the reservoir. Using a three-dimensional reservoir sand body model, the morphology and three-dimensional spatial distribution characteristics of the reservoir sand body can be characterized more clearly.
[0004] Three-dimensional seismic forward modeling primarily employs two methods: ray tracing and wave equation numerical simulation. These two methods are relatively mature and widely used. However, the pre-stack seismic data volumes calculated using ray tracing or wave equation numerical simulation require the establishment of a reasonable observation system. The resulting pre-stack gathers need to undergo processing steps such as static correction, dynamic correction, deconvolution, stacking, and migration, which can affect the objectivity of the forward modeling. Furthermore, three-dimensional pre-stack seismic forward modeling has high modeling requirements. For reservoir sand bodies in the oil reservoir development stage, the simulation results struggle to reflect the reflection characteristics of reservoirs with thin sand body thickness, poor lateral continuity, and uneven physical property distribution, making it difficult to reflect complex sedimentary features and the spatial variation patterns of various sandstone reservoirs. Summary of the Invention
[0005] In view of the shortcomings of the prior art described above, the purpose of this invention is to provide a three-dimensional seismic forward modeling method based on river sedimentary facies constraints, which uses the vertical incidence method to perform seismic forward modeling, and more objectively and effectively reflects the seismic response characteristics of different sedimentary systems and reservoir structures.
[0006] To achieve the above objectives, this invention provides a three-dimensional seismic forward modeling method based on river sedimentary facies constraints, comprising the following steps:
[0007] S1. Based on the well location distribution in the target study area, create a well-connected profile of the target study area; based on the well-connected profile, divide the target study area into several sub-layers, and then refine each sub-layer into several sand layers.
[0008] S2. Based on the well profiles and division results of the target study area, create a stratigraphic model of the target study area;
[0009] The stratigraphic model is further subdivided to obtain a subdivided stratigraphic model of the target study area.
[0010] Based on the described stratigraphic subdivision model, a stratigraphic model of the target study area is generated.
[0011] S3. Perform sedimentary facies modeling on each sub-layer of the target study area to obtain the sedimentary facies model of each sub-layer;
[0012] S4. The lithology is divided into two categories: sandstone and mudstone, so that the sedimentary facies models of each layer in the target study area are simplified to the distribution range of sandstone and mudstone.
[0013] Based on the stratigraphic model of the target study area and the sedimentary facies model of each sub-layer, a three-dimensional lithofacies model of the target study area is generated.
[0014] S5. The three-dimensional lithofacies model provides constraints, uses the acoustic logging curve as an attribute for velocity modeling, and generates a three-dimensional layer velocity model of the target study area.
[0015] S6. Obtain the velocity profile from the three-dimensional layer velocity model, generate a three-dimensional seismic forward modeling data volume from the velocity profile using the vertical incident convolution operation method, perform convolution operation on the three-dimensional seismic forward modeling data volume to obtain the seismic forward modeling profile, which is used for seismic analysis and prediction.
[0016] Furthermore, in step S2, the creation of a stratigraphic model of the target study area includes the following sub-steps:
[0017] A1. Geological interface creation: Based on the layer comparison and sub-layer division results of the target study area, the geological interfaces of each sub-layer of the target study area are directly generated in the depth domain.
[0018] A2. Setting the work area boundary and dividing the grid: Based on the distribution characteristics of the target study area, set the work area boundary polygon and divide the grid along the work area boundary polygon;
[0019] A3. Layer generation: Based on the top and bottom stratification results of each sub-layer in the target study area, the top and bottom geological interfaces of each sub-layer are generated using the well-constrained convergence interpolation method; based on the top and bottom geological interfaces of each sub-layer and the well stratification constraints, a three-dimensional lithofacies model of the target study area is generated.
[0020] Furthermore, in step S22, the polygonal boundary of the work area is rectangular.
[0021] Furthermore, in step S2, the subdivision of the stratigraphic model includes the following sub-steps:
[0022] B1. Based on the average thickness of the strata in the target study area, determine the number of vertically divided layers for each sub-layer;
[0023] B2. Divide the layers vertically and then divide each sub-layer proportionally according to the thickness of the strata.
[0024] Further, in step S6, a convolution operation is performed on the three-dimensional seismic forward modeling data volume using a Ricker wavelet with a dominant frequency of 30Hz to obtain a seismic forward modeling profile with a dominant frequency of 30Hz; a convolution operation is performed on the three-dimensional seismic forward modeling data volume using a Ricker wavelet with a dominant frequency of 60Hz to obtain a seismic forward modeling profile with a dominant frequency of 60Hz; both the 30Hz and 60Hz seismic forward modeling profiles are used for seismic analysis and prediction.
[0025] As described above, the three-dimensional seismic forward modeling method based on river sedimentary facies constraints disclosed in this invention has the following beneficial effects:
[0026] This application establishes a vertically incident forward seismic model, which establishes a connection between outcrop structures and synthetic seismic records related to well logging and core analysis. This model can not only objectively and effectively reflect the seismic response characteristics of different sedimentary systems and reservoir structures, but also flexibly adjust the seismic wavelet parameters, making it convenient to study the seismic signal variation laws of the spatiotemporal evolution of sedimentary systems and changes in reservoir lithology and physical properties. Attached Figure Description
[0027] Figure 1 This is a schematic diagram of the well location distribution and well-connection profile of the East Second Section.
[0028] Figure 2 This is a cross-sectional view of the sedimentary system in the East Second Member.
[0029] Figure 3 This is a schematic diagram of the stratigraphic structure model of the East Second Section.
[0030] Figure 4 This is a distribution map of the sandstone sedimentary system in layers d2-6 of the East Second Member.
[0031] Figure 5 This is a schematic diagram of the sedimentary facies constraint plane of layer d2-6 in the East Second Member.
[0032] Figure 6 A schematic diagram of a random sedimentary facies modeling along layers d2-6 of the East Second Member.
[0033] Figure 7 This is a schematic diagram of a three-dimensional lithofacies model of the East Second Member.
[0034] Figure 8 This is a schematic diagram of the three-dimensional layer velocity model of the East Second Segment.
[0035] Figure 9 This is a schematic diagram of a 3D seismic forward modeling data volume.
[0036] Figure 10a This is a schematic diagram showing the comparison between the seismic forward modeling profile and the rock phase obtained after convolution operation using a 30Hz main frequency Ricker wavelet.
[0037] Figure 10b This is a schematic diagram showing the comparison between the seismic forward modeling profile and the rock phase obtained after convolution operation using the 60Hz main frequency Ricker wavelet.
[0038] Figure 11 This is a flowchart of the three-dimensional seismic forward modeling method based on river sedimentary facies constraints in this application. Detailed Implementation
[0039] The following specific embodiments illustrate the implementation of the present invention. Those skilled in the art can easily understand other advantages and effects of the present invention from the content disclosed in this specification.
[0040] It should be noted that the structures, proportions, sizes, etc., depicted in the accompanying drawings of this specification are only used to complement the content disclosed in the specification, so as to enable those skilled in the art to understand and read them, and are not intended to limit the conditions under which the present invention can be implemented. Therefore, they have no substantial technical significance. Any modifications to the structure, changes in the proportions, or adjustments to the size, without affecting the effects and objectives that the present invention can produce, should still fall within the scope of the technical content disclosed in the present invention.
[0041] Furthermore, the technical solutions of the various embodiments can be combined with each other, but only if they are based on the ability of those skilled in the art to implement them. When the combination of technical solutions is contradictory or cannot be implemented, it should be considered that such combination of technical solutions does not exist and is not within the scope of protection claimed in this application.
[0042] This application provides a three-dimensional seismic forward modeling method based on river sedimentary facies constraints, such as... Figure 11 As shown, the three-dimensional seismic forward modeling method includes the following steps in sequence.
[0043] S1. Based on the well location distribution within the target study area, construct a well-connected profile for the target study area. This profile is used for well curve comparison and correction, as well as for the division and comparison of sub-layers. Based on the well-connected profile, the target study area is divided into several sub-layers, and each sub-layer is further subdivided into several sand layers, which are also known as sand groups.
[0044] S2. Based on the well profiles and division results of the target study area, a stratigraphic structural model of the target study area is created; the structural model of the target study area is further subdivided into stratigraphic subdivision models to obtain a stratigraphic subdivision model of the target study area; and a stratigraphic model is generated based on the stratigraphic subdivision model of the target study area.
[0045] S3. Perform sedimentary facies modeling on each sub-layer of the target study area to obtain the sedimentary facies model of each sub-layer.
[0046] S4. Divide the lithology into two categories: sandstone and mudstone, simplifying the sedimentary facies model of each layer in the target study area to the distribution range of sandstone and mudstone; generate a three-dimensional lithofacies model of the target study area based on the stratigraphic model of the East Second Member and the sedimentary facies model of each layer.
[0047] S5. The three-dimensional lithofacies model of the target study area provides constraints, and the sonic logging curves are used as attributes to perform velocity modeling, generating a three-dimensional layer velocity model of the target study area.
[0048] S6. Obtain the velocity profile from the three-dimensional layer velocity model of the target study area, generate a three-dimensional seismic forward modeling data volume from the velocity profile using the vertical incident convolution operation method, perform convolution operation on the three-dimensional seismic forward modeling data volume to obtain the seismic forward modeling profile, which is used for seismic analysis and prediction.
[0049] This application establishes a vertically incident forward seismic model, which establishes a connection between outcrop structures and synthetic seismic records related to well logging and core analysis. This model can not only objectively and effectively reflect the seismic response characteristics of different sedimentary systems and reservoir structures, but also flexibly adjust the seismic wavelet parameters, making it convenient to study the seismic signal variation laws of the spatiotemporal evolution of sedimentary systems and changes in reservoir lithology and physical properties.
[0050] The following description uses the Dongying Formation 2 Member in a certain work area as an example to illustrate the above-mentioned three-dimensional seismic forward modeling method based on fluvial sedimentary facies constraints. The Dongying Formation 2 Member in a certain work area will be referred to as the Dong 2 Member.
[0051] I. Stratigraphic correlation and sand body development analysis.
[0052] The second eastern section consists of gray and grayish-white conglomerate sandstone, fine-grained sandstone, and variegated mudstone in alternating layers of varying thickness. The upper part of the second eastern section, the first eastern section, has been eroded. The second eastern section is in direct contact with the overlying Guantao Formation, forming an unconformable contact. The lower part of the second eastern section, the third eastern section, is mainly composed of dark gray mudstone, interbedded with thin layers of fine-grained sandstone and light gray and grayish-white conglomerate sandstone.
[0053] like Figure 1 As shown, there are 51 wells in the East Second Member. Based on the well location distribution of these 51 wells, a well-connected profile was created. According to the well-connected profile, the East Second Member is divided into 9 sub-layers: d2-1, d2-2, d2-3, d2-4, d2-5, d2-6, d2-7, d2-8, and d2-9. Each sub-layer is further subdivided into several sand layers. Based on the well-connected profile, a cross-sectional diagram of the sedimentary system of the East Second Member was created using software, as shown below. Figure 2 As shown in the cross-sectional diagram of the sedimentary system in the East Second Member, the sedimentary system in the East Second Member is a three-stage sedimentary system in the vertical direction, and the source of the sediment comes from the west; the channel sand bodies have good lateral connectivity, and the individual channel sand bodies are relatively large, indicating that the physical properties of the sand bodies in this area are good; the mouth bar and underwater distributary channels are also well developed and have good extensibility.
[0054] II. Construction and Modeling.
[0055] The preferred construction modeling includes the following steps:
[0056] 2.1 Geological Interface Creation: Using the layered comparison and sub-layer division results of the Dong Erduan section of the dense well network, the geological interfaces of each sub-layer are directly generated in the depth domain for structural modeling.
[0057] 2.2. Setting the work area boundary and mesh generation: Based on the distribution characteristics of the East Second Segment, a polygonal boundary is set for the work area. Preferably, the work area boundary is set as a rectangle, and the mesh is generated along the rectangular boundary to facilitate the generation of 3D seismic data volumes; furthermore, the line directions of the 3D seismic data volumes generated later also follow the rectangular boundary of the work area.
[0058] 2.3 Layer Generation: Utilizing the top and bottom stratification results of each sub-layer in the Dong'er Member, and employing well-constrained convergent interpolation methods, the top and bottom geological interfaces of each sub-layer are generated. These interfaces serve as the interface constraints for generating the structural model. Based on the top and bottom geological interfaces of each sub-layer and the well-constrained stratification, the stratigraphic structural model (i.e., stratigraphic framework) of the Dong'er Member is generated, such as... Figure 3 As shown.
[0059] 2.4 Stratigraphic Subdivision: Based on the average thickness of the strata in the East Second Member, a vertical subdivision number is set for each sub-layer. If the sedimentation is relatively stable, the subdivision can be proportional to the strata thickness. When subdividing the strata proportionally, the grid division scale can be adjusted appropriately according to the thinning of the strata to reduce the computational load.
[0060] III. Sedimentary facies modeling.
[0061] Sedimentary facies modeling was performed on each sub-layer of the Dong 2 Member to obtain the sedimentary facies model for each sub-layer. The following explanation uses layer d2-6 of the Dong 2 Member as an example.
[0062] The distribution of the sandstone sedimentary system in layers d2-6 of the East Second Member is as follows: Figure 4 As shown. Figure 4 In the diagram, P1 represents an underwater distributary channel, P2 represents an estuary bar, P3 represents a distal bar, P4 represents an inter-bay, P5 represents a small lake, and P6 represents a borehole. From... Figure 5It can be seen that: layer d2-6 is a sedimentary environment dominated by underwater distributary channels. Underwater distributary channels and mouth bars are mainly distributed in the upper part of layer d2-6 and are relatively thick; bays and marshes are mainly distributed in the bottom of layer d2-6.
[0063] Using the obtained sedimentary system distribution map, various sedimentary facies units are coded to generate planar constraints for sedimentary facies modeling. Figure 5 It is based on Figure 4 The sedimentary facies constraint plane for the d2-6 layer is obtained after lithological coding of the sedimentary facies map. Under the coded sedimentary facies constraint, the sedimentary facies modeling results will generally be consistent with the sedimentary facies constraint plane, thus ensuring that the obtained sedimentary facies model matches the well logging results, and that the spatial distribution is consistent with the distribution characteristics of the sedimentary system.
[0064] Figure 6 Based on Figure 5 The sedimentary facies modeling results for layer d2-6 under planar constraints are obtained through sedimentary facies modeling. During the range function analysis of sedimentary facies simulation, it is necessary to fully consider the sedimentary type and spatial distribution characteristics of the sedimentary system. For sedimentary systems dominated by underwater distributary channels, it is necessary to consider the main river direction, the range of variation in main channel width and thickness, and the characteristics of riverbank sediments.
[0065] IV. Modeling of sandstone and mudstone lithofacies.
[0066] In this embodiment, the lithology is divided into two categories: sandstone and mudstone, thereby simplifying the complexity of the lithology model. Consequently, the sedimentary facies models of each sublayer in the East Second Member are also simplified to sandstone and mudstone distribution ranges. Mudstone is mainly found in lacustrine, swamp, and interbay areas; sandstone is mainly found in river channels, channel zones, crevasse fans, mouth bars, and distal bars.
[0067] Through statistical analysis of lithology, the lateral and longitudinal probability distributions of each small layer of sand bodies in the East Second Member were obtained. Based on this, the probability distribution function of each small layer of sand bodies was established, which provides reasonable constraints for lithological modeling.
[0068] The variation function is obtained based on data analysis; after coarsening the well logging lithology curves, lithofacies simulation is performed according to the variation function. In this embodiment, the lithofacies modeling simulation method adopts sequential exponential simulation. Based on the stratigraphic model of the Dong-2 Member and the sedimentary facies models of each sublayer, a three-dimensional lithofacies model of the Dong-2 Member is generated, such as... Figure 7 As shown, the three-dimensional lithofacies model provides constraints for generating the subsequent three-dimensional layer velocity model. Figure 7 In the diagram, the gray areas represent mudstone, and the black areas represent sandstone.
[0069] V. Velocity attribute modeling.
[0070] Velocity modeling was performed using attribute modeling methods and utilizing sonic logging curves. Specifically, sonic logging curves were used as attributes, and the aforementioned three-dimensional lithofacies model of the Dong-2 formation provided constraints. The attribute modeling module provided by Petrel software was used for velocity modeling to generate a three-dimensional layer velocity model of the Dong-2 formation, such as... Figure 8 As shown, this provides the conditions for subsequent earthquake forward modeling.
[0071] VI. Seismic forward modeling simulation.
[0072] On the three-dimensional layer velocity model of the East Second Member, seismic forward modeling is performed using the vertical incidence convolution method. This method can objectively and effectively analyze the seismic response characteristics of complex underground reservoir sand bodies, reflecting the seismic response characteristics of different sedimentary systems and reservoir structures. It also allows for flexible adjustment of seismic wavelet parameters, facilitating the study of seismic signal variations in the spatiotemporal evolution of sedimentary systems and changes in reservoir lithology and physical properties. In areas with gentle stratigraphic undulations and stable sedimentation, the seismic records obtained by the vertical incidence method do not require complex seismic acquisition and processing, enabling simple and effective three-dimensional seismic forward modeling. This allows researchers to focus on detailed stratigraphic simulation modeling and the seismic response characteristics of complex sand body distributions. Figure 8 The velocity model calculates the reflection coefficient, the seismic wavelet is set, and a three-dimensional seismic forward modeling data volume is generated according to the vertical incidence convolution operation method, such as... Figure 9 As shown.
[0073] Convolution operations are performed on the 3D seismic forward modeling data volume to obtain the seismic forward modeling profile. In this embodiment, the comparison results between the seismic forward modeling profile and the rock revelation are obtained after convolution operations using a Ricker wavelet with a dominant frequency of 30Hz. Figure 10a As shown; in Figure 10a On the seismic forward model profile with a dominant frequency of 30Hz, the amplitude and waveform structure reflect the wave group characteristics of different layers. However, due to the low resolution, the phase axes cannot provide a detailed characterization of the interbedded sandstone and mudstone. The comparison between the seismic forward model profile and the rock revelation is obtained after convolution using a Ricker wavelet with a dominant frequency of 60Hz. Figure 10b As shown; in Figure 10b On the 60Hz main frequency seismic forward modeling profile shown, the correspondence between the seismic reflection phase axis and the sand body is significantly improved. The magnitude and extension range of the seismic phase axis are significantly correlated with the sand body, and the waveform structure also shows a significant correspondence with the spatial occurrence state of the reservoir sand and mudstone.
[0074] Based on seismic forward modeling, we can see the seismic reflection characteristics caused by changes in different lithologies. Based on the correspondence between lithological profiles and 3D seismic forward modeling data volumes, we can obtain the corresponding fluctuations caused by data combination relationships, which can be better used for earthquake analysis and prediction.
[0075] In summary, this application establishes a link between outcrop structures and synthetic seismic records associated with well logging and core samples by building a vertically incident forward seismic model. Specifically, this application uses sedimentary facies-constrained 3D attribute modeling, guided by sedimentology, and utilizes sedimentary facies models established from drilling and logging data to construct a 3D stratigraphic attribute model. This effectively reflects the seismic response characteristics of different sedimentary systems and reservoir structures, and facilitates the study of seismic signal variations in the spatiotemporal evolution of sedimentary systems and changes in reservoir lithology and physical properties. Furthermore, this application performs seismic forward simulation based on velocity modeling and convolution operations. The seismic records obtained using the vertically incident method are equivalent to zero-offset gathers, eliminating the need for complex seismic acquisition and processing. This allows for simple and effective 3D seismic forward simulation, enabling researchers to focus on detailed stratigraphic simulation modeling and the seismic response characteristics of complex sand body distributions. It not only objectively and effectively reflects the seismic response characteristics of different sedimentary systems and reservoir structures but also allows for flexible adjustment of seismic wavelet parameters, facilitating the study of seismic signal variations in the spatiotemporal evolution of sedimentary systems and changes in reservoir lithology and physical properties.
[0076] Therefore, this application establishes a high-precision sequence stratigraphic structure model (i.e., stratigraphic framework) by identifying well-seismic isochronous surfaces and analyzing their geological meaning. It then constructs a three-dimensional velocity model using sedimentary facies constraints and conducts three-dimensional seismic forward modeling. This method is not only simple and easy to implement, but also effectively studies the seismic signal variation law of lateral non-uniform changes in sand bodies, demonstrating the practicality and effectiveness of various prediction techniques in seismic sedimentology.
[0077] In summary, this invention effectively overcomes the various shortcomings of the prior art and has high industrial application value.
[0078] The above embodiments are merely illustrative of the principles and effects of the present invention and are not intended to limit the invention. Any person skilled in the art can modify or alter the above embodiments without departing from the spirit and scope of the present invention. Therefore, all equivalent modifications or alterations made by those skilled in the art without departing from the spirit and technical concept disclosed in the present invention should still be covered by the claims of the present invention.
Claims
1. A three-dimensional seismic forward modeling method based on river sedimentary facies constraints, characterized in that: Includes the following steps: S1. Based on the well location distribution in the target study area, create a well-connected profile of the target study area; based on the well-connected profile, divide the target study area into several sub-layers, and then refine each sub-layer into several sand layers. S2. Based on the well profiles and division results of the target study area, create a stratigraphic model of the target study area; The stratigraphic model is further subdivided to obtain a subdivided stratigraphic model of the target study area. Based on the described stratigraphic subdivision model, a stratigraphic model of the target study area is generated. S3. Perform sedimentary facies modeling on each sub-layer of the target study area to obtain the sedimentary facies model of each sub-layer; S4. The lithology is divided into two categories: sandstone and mudstone, so that the sedimentary facies models of each layer in the target study area are simplified to the distribution range of sandstone and mudstone. Based on the stratigraphic model of the target study area and the sedimentary facies model of each sub-layer, a three-dimensional lithofacies model of the target study area is generated. S5. The three-dimensional lithofacies model provides constraints, uses the acoustic logging curve as an attribute for velocity modeling, and generates a three-dimensional layer velocity model of the target study area. S6. Obtain the velocity profile from the three-dimensional layer velocity model, generate a three-dimensional seismic forward modeling data volume from the velocity profile using the vertical incident convolution operation method, perform convolution operation on the three-dimensional seismic forward modeling data volume to obtain the seismic forward modeling profile, which is used for seismic analysis and prediction.
2. The three-dimensional seismic forward modeling method according to claim 1, characterized in that: In step S2, the creation of the stratigraphic model of the target study area includes the following sub-steps: A1. Geological interface creation: Based on the layer comparison and sub-layer division results of the target study area, the geological interfaces of each sub-layer of the target study area are directly generated in the depth domain. A2. Setting the work area boundary and dividing the grid: Based on the distribution characteristics of the target study area, set the work area boundary polygon and divide the grid along the work area boundary polygon; A3. Layer Generation: Based on the top and bottom stratification results of each sub-layer in the target study area, the top and bottom geological interfaces of each sub-layer are generated using the well-constrained convergence interpolation method; based on the top and bottom geological interfaces of each sub-layer and the well stratification constraints, the stratigraphic structure model of the target study area is generated.
3. The three-dimensional seismic forward modeling method according to claim 2, characterized in that: In step A2, the boundary polygon of the work area is rectangular.
4. The three-dimensional seismic forward modeling method according to claim 1, characterized in that: In step S2, the subdivision of the stratigraphic model includes the following sub-steps: B1. Based on the average thickness of the strata in the target study area, determine the number of vertically divided layers for each sub-layer; B2. Divide the layers vertically and then divide each sub-layer proportionally according to the thickness of the strata.
5. The three-dimensional seismic forward modeling method according to claim 1, characterized in that: In step S6, a convolution operation is performed on the three-dimensional seismic forward modeling data volume using a Ricker wavelet with a dominant frequency of 30Hz to obtain a seismic forward modeling profile with a dominant frequency of 30Hz; a convolution operation is also performed on the three-dimensional seismic forward modeling data volume using a Ricker wavelet with a dominant frequency of 60Hz to obtain a seismic forward modeling profile with a dominant frequency of 60Hz; both the 30Hz and 60Hz seismic forward modeling profiles are used for seismic analysis and prediction.