Initial prestack migration velocity modeling method and device based on geological constraints

Abstract

The present invention discloses a method and device for initial pre-stack migration velocity modeling based on geological constraints, which belongs to the field of oil and gas seismic exploration. The present invention collects data to obtain the stratigraphic reflection layer and fault data of the velocity control layer of the three-dimensional seismic pre-stack time migration data body, establishes a structural grid model in the time domain, determines the velocity control points of each layer segment, obtains the initial velocity model, and combines it with the constrained tomographic inversion near-surface velocity model to construct an initial pre-stack migration velocity model based on geological constraints. The modeling method proposed in the present invention processes the original data into a frequency that matches the processing frequency when determining the velocity control points of each layer segment, so that the obtained velocity is closer to the velocity of the real formation. The present invention can solve the problem of poor initial migration effect in conventional processing, greatly improve the accuracy of seismic data migration imaging, provide more reliable basic data for seismic exploration, and facilitate promotion and application in other three-dimensional seismic processing.

Description

Technical Field

[0001] The present invention belongs to the field of oil and gas seismic exploration and relates to a geophysical signal interpretation, in particular to an initial pre-stack migration velocity modeling method and device based on geological constraints. Background Art

[0002] In the exploration and development of oil and gas fields, the application of seismic results is particularly important. The imaging accuracy of seismic data directly affects the deployment and tracking of well locations. In order to improve the imaging accuracy of seismic data, it is necessary to focus on the offset processing.

[0003] Typically, the initial velocity model used in previous prestack time migration or prestack depth migration is based on the empirical constant velocity given by the processor. This constant velocity is far from the actual velocity and does not take into account the velocity changes in the vertical and horizontal directions, nor the differences in marine and terrestrial geological conditions. The initial migration greatly affects the imaging accuracy and ultimately the final imaging accuracy of the seismic data, which is far from meeting the current demand for seismic data in oil and gas fields. Summary of the Invention

[0004] The technical problem to be solved by the present invention is to provide a method and device for initial prestack migration velocity modeling based on geological constraints, so as to improve the accuracy of processing initial migration imaging and further improve the accuracy of the final processing results.

[0005] In order to achieve the above object, the technical solution adopted by the present invention is:

[0006] A method for initial prestack migration velocity modeling based on geological constraints, comprising the following steps:

[0007] S1. Data Collection

[0008] Collect data and obtain 3D seismic pre-stack time migration data volume in the work area;

[0009] S2. Obtaining stratigraphic reflection horizons and fault data for the velocity-controlling layer of the 3D seismic prestack time migration data volume

[0010] Interpret the 3D seismic profile layers and faults in the work area to obtain stratigraphic reflection layer and fault data of the velocity control layer of the 3D seismic prestack time migration data volume;

[0011] S3. Establish a structural framework model in the time domain and determine the velocity control points of each layer

[0012] Based on the stratigraphic reflection horizons and faults of the velocity control layer of the 3D seismic prestack time migration data volume, a time domain structural framework model is established according to the fault cutting relationship and stratigraphic sequence;

[0013] Determine the velocity control points of each layer based on the sonic curve or VSP logging curve;

[0014] S4. Obtaining the initial velocity model

[0015] Based on the velocity control points of each layer, the structural grid model in the time domain is velocity-filled to obtain an initial velocity model;

[0016] S5. Constructing an initial prestack migration velocity model based on geological constraints

[0017] The constrained tomographic inversion near-surface velocity model is combined with the initial velocity model to construct an initial prestack migration velocity model based on geological constraints.

[0018] Preferably, in step S1, the data includes original seismic data;

[0019] In step S2, after interpreting the 3D seismic profile layers and faults in the work area, a seismic reflection interface with a large velocity variation difference and a strong wave impedance interface is found as the velocity control layer of the work area, and the layer position of the velocity control layer is tracked on the 3D seismic prestack time migration data volume;

[0020] The speed change difference is large and the speed change difference is not less than 1000m / s;

[0021] The wave impedance interface is relatively strong and is an interface that has been accurately identified and judged by humans and can be continuously tracked.

[0022] Preferably, in step S3, the sonic curve or VSP logging curve is thinned out, and the thinned out points include points of important seismic reflection layers, and the velocity control points of each layer are obtained in combination with the processing frequency.

[0023] Preferably, the processing frequency is selected as follows: the processing frequency for terrestrial strata is 3.6-4.4 Hz, and the processing frequency for marine strata is 1.8-2.2 Hz.

[0024] Preferably, step S4 includes:

[0025] Based on the velocity control points of each layer, the time-domain structural grid model is filled with velocities both horizontally and vertically to generate an initial velocity model. Transverse velocity variations are constrained between wells, and velocity variations are interpolated using the trends of stratigraphic variations in the time-domain structural grid model. Vertical velocity variations depend on the stratigraphic formation or selected velocity points, and locations without wells are interpolated based on stratigraphic sequence or annihilation.

[0026] Preferably, in step S5, the constrained tomographic inversion near-surface velocity model is obtained by constrained tomographic inversion using surface VSP logging data;

[0027] Combining the constrained tomographic inversion near-surface velocity model with the initial velocity model includes: replacing the near-surface velocity model with the constrained tomographic inversion near-surface velocity model, and continuing to use the initial model for the deep velocity model.

[0028] The present invention also provides a device for executing the above-mentioned initial prestack migration velocity modeling method based on geological constraints, the device comprising a 3D seismic prestack time migration data volume acquisition module, a stratigraphic reflection horizon and fault acquisition module, a structural grid model and velocity control point acquisition module, an initial velocity model acquisition module, and an initial prestack depth migration velocity model acquisition module based on geological constraints;

[0029] The 3D seismic pre-stack time migration data volume acquisition module is used to acquire the 3D seismic pre-stack time migration data volume of the work area based on the collected original seismic data;

[0030] The stratigraphic reflection layer and fault acquisition module is used to interpret the 3D seismic profile layers and faults in the work area and obtain stratigraphic reflection layer and fault data of the velocity control layer of the 3D seismic prestack time migration data volume;

[0031] The structural grid model and velocity control point acquisition module is used to establish a time-domain structural grid model based on the stratigraphic reflection horizons and faults of the velocity control layer of the 3D pre-stack time migration data volume, in accordance with the fault-cutting relationship and stratigraphic sequence; and is also used to determine the velocity control points of each layer according to the acoustic wave curve or VSP logging curve;

[0032] The initial velocity model acquisition module is used to perform velocity filling on the structural grid model in the time domain based on the velocity control points of each layer to obtain an initial velocity model;

[0033] The initial pre-stack depth migration velocity model acquisition module based on geological constraints is used to combine the constrained tomographic inversion near-surface velocity model with the initial velocity model to construct an initial pre-stack migration velocity model based on geological constraints.

[0034] The present invention also provides a computer device, which includes a processor and a computer program stored in a memory and executable on the processor. When the processor executes the computer program, the above-mentioned initial prestack migration velocity modeling method based on geological constraints is implemented.

[0035] The present invention also provides a computer-readable storage medium storing a computer program for executing the above-mentioned initial prestack migration velocity modeling method based on geological constraints.

[0036] Due to the adoption of the above technical solution, the present invention has the following technical advancements compared with the prior art:

[0037] ① The present invention utilizes VSP logging or sonic logging data and three-dimensional seismic data to track horizons and interpret faults. After constructing a time-domain structural grid model, a constrained tomographic inversion near-surface velocity model, and an initial velocity model, the two velocity models are combined, replacing the near-surface velocity model with the constrained tomographic inversion near-surface velocity model. The initial velocity model is used for deep layers below the high-velocity layer, thereby obtaining an initial prestack migration velocity model based on geological constraints. The present invention can solve the problem of poor initial migration effect in conventional processing, greatly improve the accuracy of seismic data migration imaging, provide more reliable basic data for seismic exploration, contribute to the iteration and development of high-precision geophysical exploration technology, and facilitate its promotion and application in other three-dimensional seismic processing.

[0038] ② The initial prestack migration velocity modeling method based on geological constraints proposed in this invention uses VSP well logging curves or acoustic wave data to extract frequencies that match the seismic processing velocity frequency when determining the velocity control points of each layer. This method is superior to the conventional velocity model construction that uses the average velocity of a layer in the well logging as the velocity control point. The velocity obtained by the method provided by this invention is closer to the velocity of the actual formation. The strata in terrestrial strata change relatively quickly, and the processing frequency is preferably selected to be around 4Hz; the strata in marine strata change relatively slowly, and the processing frequency is preferably selected to be around 2Hz.

[0039] ③ The present invention also provides electronic equipment and storage media for executing the method for three-dimensional seismic spatial positioning of horizontal well geological steering images, with complete software and hardware supporting facilities, which facilitates the promotion and use of the testing method.

[0040] The present invention is applied to establishing a seismic migration velocity model, especially an initial migration velocity model for pre-stack depth migration, and can also be further applied to other three-dimensional seismic processing. BRIEF DESCRIPTION OF THE DRAWINGS

[0041] The present invention will be described in further detail below with reference to the accompanying drawings and specific embodiments.

[0042] Figure 1 This is a flow chart of the initial prestack migration velocity modeling method based on geological constraints in Example 1 of the present invention;

[0043] Figure 2 This is a velocity comparison diagram of velocity control points of each layer of the three-dimensional H203 well obtained by different processing methods in Example 1 of the present invention;

[0044] Figure 3 A cross-sectional comparison diagram of the initial prestack migration velocity of the three-dimensional H203 well obtained by the conventional method in Example 1 of the present invention and the method provided by the present invention;

[0045] Figure 4This is a structural block diagram of an apparatus for an initial prestack migration velocity modeling method based on geological constraints in Example 4 of the present invention;

[0046] Figure 5 This is a structural block diagram of a computer device in Example 5 of the present invention. DETAILED DESCRIPTION

[0047] The present invention will be further described in detail below by means of specific embodiments in conjunction with the accompanying drawings. It should be understood that the embodiments described are preferred examples of the present invention and are only used to explain the present invention and are not intended to limit the present invention.

[0048] In step S3 of the embodiment, the processing frequency of the terrestrial strata can be selected from 3.6 to 4.4 Hz, and the corresponding sampling frequency is one point every 180 to 220 m; the processing frequency of the marine strata can be selected from 1.8 to 2.2 Hz, and the corresponding sampling frequency is one point every 360 to 440 m.

[0049] The processing frequency of the continental strata may be 3.6 Hz, 3.8 Hz, 4.0 Hz, 4.2 Hz, 4.4 Hz, and other typical but non-limiting frequencies. The processing frequency is determined based on the thickness of the strata with large formation velocity variations.

[0050] The processing frequency of the marine strata may be a typical but non-limiting frequency such as 1.8 Hz, 2.0 Hz, or 2.2 Hz, and the processing frequency is determined based on the thickness of the stratum where the stratum velocity variation is large.

[0051] Example 1 A method for initial prestack migration velocity modeling based on geological constraints

[0052] (I) This embodiment provides an initial prestack migration velocity modeling method based on geological constraints, the flow chart of which is as follows: Figure 1 As shown, the method includes the following steps performed in sequence:

[0053] S1. Data Collection

[0054] Collecting raw seismic data including raw gathers in raw seismic data or 3D seismic prestack depth migration data volumes;

[0055] Obtain a 3D seismic prestack time migration data volume using a time migration processing method based on the original gathers in the original seismic data; or

[0056] According to the 3D seismic prestack depth migration data volume, the depth migration processing method is used to convert it into a 3D seismic prestack time migration data volume;

[0057] S2. Obtaining stratigraphic reflection horizons and fault data for the velocity-controlling layer of the 3D seismic prestack time migration data volume

[0058] Interpret the 3D seismic profile layers and faults in the work area. Based on the velocity variation structure of the strata in the work area, find the seismic reflection interface with large velocity variation difference and strong wave impedance interface to obtain the velocity control layer of the work area.

[0059] Perform horizon tracking of velocity control layers on 3D seismic prestack time migration data to obtain time domain seismic reflection horizon data and fault data of each velocity control layer in the work area;

[0060] The large velocity variation difference is a velocity variation difference of not less than 1000 m / s; the strong wave impedance interface is an interface that has been accurately identified and determined manually and can be continuously tracked; the selected velocity control layer is usually a regionally representative layer with a stable fault reflection structure.

[0061] S3. Establish a structural framework model in the time domain and determine the velocity control points of each layer

[0062] This step includes establishing a structural grid model in the time domain and determining the velocity control points of each layer. Specifically, it includes:

[0063] S31. Establishment of the structural grid model

[0064] S311. Smooth the seismic reflection horizons and fill and repair the seismic reflection horizons throughout the work area according to the horizon change trend;

[0065] S312. Check and adjust each fault plane to ensure that each fault plane is smooth;

[0066] S313. Using the adjusted time-domain seismic reflection horizons and the adjusted faults, a time-domain structural framework model is established according to the fault-cutting relationship and stratigraphic sequence to obtain a time-domain structural framework model;

[0067] S32. Determination of velocity control points in each layer

[0068] S321. Select an acoustic log or VSP log with no velocity anomalies within the work area. If a VSP log is available, use the VSP log whenever possible. If no VSP log is available, use the acoustic log instead.

[0069] S322. Thin out the selected VSP logging curves or acoustic wave curves to ensure that every important seismic reflection layer is included as much as possible. Furthermore, the processing frequency is combined to determine the velocity control points for each interval. For terrestrial formations, the processing frequency is 4.0 Hz, corresponding to a sampling frequency of one point every 200 m. For marine formations, the processing frequency is 2.0 Hz, corresponding to a sampling frequency of one point every 400 m.

[0070] The velocity frequency recorded in sonic logging or VSP logging is relatively high (sampling frequency, such as 0.25 m, 1 m, or 5 m). Conventional processing methods generally directly use the average velocity in sonic logging or VSP logging as the velocity control point. However, this processing method results in low accuracy in the resulting seismic profile imaging.

[0071] S4. Obtaining the initial velocity model

[0072] Based on the velocity control points of each layer, the time domain structural grid model is filled with velocity horizontally and vertically. The horizontal velocity change mainly considers the change between wells, and the vertical velocity change mainly considers the change in the vertical direction of the well and the change in the formation structure. Then, an appropriate interpolation method is selected to interpolate to obtain an initial velocity model, which may specifically include:

[0073] Based on the velocity control points of each layer, the time domain structural grid model is horizontally filled with velocity. The horizontal change of velocity adopts the constraint between wells. The velocity change is interpolated using the trend of formation change of the time domain structural grid model to obtain the velocity body of the time domain with horizontal velocity filling. The interpolation method is Kriging interpolation method or inverse distance weighted interpolation method. At the same time,

[0074] The time domain structural grid model is filled with velocity vertically. The vertical variation mainly depends on the stratum or the selected velocity points. The locations without wells are mainly based on the stratum sequence or annihilation situation. The velocity volume of the time domain filled with velocity vertically is obtained by interpolation in the manner of parallel to the stratum, parallel to the top or parallel to the bottom.

[0075] After filling the time domain structural grid model with velocity in the horizontal and vertical directions, the initial velocity model is obtained;

[0076] S5. Constructing an initial prestack migration velocity model based on geological constraints

[0077] Based on the initial seismic reflection values ​​picked up from the surface VSP logging data, the constrained tomographic inversion method is used to obtain the constrained tomographic inversion near-surface velocity model;

[0078] The near-surface velocity model is combined with the initial velocity model. The velocity model of the near-surface (above the high-velocity layer) is replaced with the constrained tomographic inversion near-surface velocity model, while the initial velocity model is used in the deep layer (below the high-velocity layer) to obtain the initial prestack migration velocity model based on geological constraints.

[0079] (II) To verify the importance of the processing frequency selected when constructing the initial prestack migration velocity model of the present invention, a comparative example was prepared to examine the differences between the comparative example and the initial prestack migration velocity model construction method provided by the present invention in the velocity profiles of the velocity control layer and the final initial prestack migration velocity. The three-dimensional H203 well in the H205 well area was used as an example for illustration. The specific method is as follows:

[0080] Preparation of the comparative example: The method for constructing the initial prestack migration velocity model in the comparative example differs from the method for constructing the initial prestack migration velocity model based on geological constraints described in Part (I) of this example only in step "S32. Determination of velocity control points for each layer". In the comparative example, the original constants in the three-dimensional VSP logging curve with no velocity anomalies in the H203 well are selected as the velocity control points for each layer according to the conventional method, while the remaining steps and parameter selections are the same.

[0081] The comparison diagram of the velocity control layer velocity and the cross-sectional comparison diagram of the final initial pre-stack migration velocity are shown in the comparative embodiment and the initial pre-stack migration velocity model construction method provided by the present invention. Figures 2 and 3 shown.

[0082] Depend on Figures 2 and 3 It can be seen that conventional methods use a constant as the velocity of the velocity-controlling layer; however, the velocity of the velocity-controlling layer of the present invention matches the frequency of the formation thickness in the set with large formation velocity variations, and the velocities of different velocity-controlling layers vary with the geology. The initial prestack migration velocity profile obtained by the present invention exhibits better overall wave group characteristics than that obtained by conventional methods, with significantly improved main component imaging, better focus at most locations, and clearer cross-sections.

[0083] The initial pre-stack migration velocity modeling method based on geological constraints provided by the present invention has been well applied in shale gas 3D seismic in the Sichuan Basin. 2 It has been well applied in seismic projects with remarkable application effects, which has supported the deployment and tracking of more than 200 shale gas horizontal wells and supported the high-quality and efficient completion of seismic well location tracking effect evaluation.

[0084] Example 2: An initial prestack migration velocity modeling method based on geological constraints

[0085] This embodiment provides an initial prestack migration velocity modeling method based on geological constraints. The specific modeling method is basically the same as the steps of the embodiment. The only difference is that in step S322, the processing frequency of the terrestrial strata is selected as 3.6 Hz, and the corresponding sampling frequency is one point every 220 m; the processing frequency of the marine strata is selected as 1.8 Hz, and the corresponding sampling frequency is one point every 440 m.

[0086] Example 3: A method for initial prestack migration velocity modeling based on geological constraints

[0087] This embodiment provides an initial prestack migration velocity modeling method based on geological constraints. The specific modeling method is basically the same as the steps of the embodiment. The only difference is that in step S322, the processing frequency of the terrestrial strata is selected as 4.4 Hz, and the corresponding sampling frequency is one point every 180 m; the processing frequency of the marine strata is selected as 2.2 Hz, and the corresponding sampling frequency is one point every 360 m.

[0088] Example 4: An apparatus for an initial prestack migration velocity modeling method based on geological constraints

[0089] This embodiment provides a device for executing the above-mentioned initial prestack migration velocity modeling method based on geological constraints. The structural block diagram of the device is shown in FIG. Figure 4 As shown, it specifically includes a 3D seismic pre-stack time migration data volume acquisition module, a stratigraphic reflection layer and fault acquisition module, a structural grid model and velocity control point acquisition module, an initial velocity model acquisition module, and an initial pre-stack depth migration velocity model acquisition module based on geological constraints;

[0090] The 3D seismic pre-stack time migration data volume acquisition module is used to acquire the 3D seismic pre-stack time migration data volume of the work area;

[0091] The stratigraphic reflection layer and fault acquisition module is used to interpret the 3D seismic profile layers and faults in the work area and obtain stratigraphic reflection layer and fault data of the velocity control layer of the 3D seismic prestack time migration data volume;

[0092] The structural grid model and velocity control point acquisition module is used to establish a time-domain structural grid model based on the stratigraphic reflection horizons and faults of the velocity control layer of the 3D pre-stack time migration data volume, in accordance with the fault-cutting relationship and stratigraphic sequence; and is also used to determine the velocity control points of each layer according to the acoustic wave curve or VSP logging curve;

[0093] The initial velocity model acquisition module is used to perform velocity filling on the structural grid model in the time domain based on the velocity control points of each layer to obtain an initial velocity model;

[0094] The initial pre-stack depth migration velocity model acquisition module based on geological constraints is used to combine the constrained tomographic inversion near-surface velocity model with the initial velocity model to construct an initial pre-stack migration velocity model based on geological constraints.

[0095] Example 5: Computer device

[0096] This embodiment provides a computer device. The structural block diagram of the computer device is as follows: Figure 5As shown, it specifically includes: a memory, a processor, and a computer program stored in the memory and executable on the processor to implement the above-mentioned initial prestack migration velocity modeling method based on geological constraints.

[0097] The above-mentioned memory is used to store non-transitory computer-readable instructions. Specifically, the memory may include one or more computer program products, which may include various forms of computer-readable storage media, such as volatile memory and / or non-volatile memory. The volatile memory may include, for example, random access memory (RAM) and / or cache memory. The non-volatile memory may include, for example, read-only memory (ROM), a hard disk, flash memory, etc.

[0098] The processor may be a central processing unit (CPU) or other processing unit having data processing capability and / or instruction execution capability, and may control other components in the electronic device to perform desired functions. The processor is configured to execute the computer-readable instructions stored in the memory.

[0099] Those skilled in the art should understand that in order to solve the technical problem of how to obtain a good user experience, this 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 scope of protection of this disclosure.

[0100] Example 6 A computer-readable storage medium

[0101] This embodiment provides a computer-readable storage medium storing a computer program. When the computer program is executed by a processor, the computer program implements the above-mentioned initial prestack migration velocity modeling method based on geological constraints.

[0102] The computer-readable storage medium stores non-transitory computer-readable instructions, which, when executed by a processor, execute all or part of the steps of the aforementioned methods.

[0103] The above-mentioned computer-readable storage media include, but are not limited to, optical storage media (e.g., CD-ROMs and DVDs), magneto-optical storage media (e.g., MOs), magnetic storage media (e.g., magnetic tapes or mobile hard disks), media with built-in rewritable non-volatile memory (e.g., memory cards), and media with built-in ROM (e.g., ROM cartridges).

[0104] The above description is merely an optional embodiment of the present disclosure and is not intended to limit the present disclosure. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principles of the present disclosure shall be included in the scope of protection of the present disclosure.

Claims

1. A method for initial prestack migration velocity modeling based on geological constraints, characterized in that: The method comprises the following steps performed in sequence: S1. Data Collection Collect data and obtain 3D seismic pre-stack time migration data volume in the work area; S2. Obtaining stratigraphic reflection horizons and fault data for the velocity-controlling layer of the 3D seismic prestack time migration data volume Interpret the 3D seismic profile layers and faults in the work area to obtain stratigraphic reflection layer and fault data of the velocity control layer of the 3D seismic prestack time migration data volume; S3. Establish a structural framework model in the time domain and determine the velocity control points of each layer Based on the stratigraphic reflection horizons and faults of the velocity control layer of the 3D seismic prestack time migration data volume, a time domain structural framework model is established according to the fault cutting relationship and stratigraphic sequence; Determine the velocity control points of each layer based on the sonic curve or VSP logging curve; S4. Obtaining the initial velocity model Based on the velocity control points of each layer, the structural grid model in the time domain is velocity-filled to obtain an initial velocity model; S5. Constructing an initial prestack migration velocity model based on geological constraints The constrained tomographic inversion near-surface velocity model is combined with the initial velocity model to construct an initial prestack migration velocity model based on geological constraints.

2. The initial prestack migration velocity modeling method based on geological constraints according to claim 1 is characterized in that: In step S1, the data includes original seismic data; In step S2, after interpreting the 3D seismic profile layers and faults in the work area, a seismic reflection interface with a large velocity variation difference and a strong wave impedance interface is found as the velocity control layer of the work area, and the layer position of the velocity control layer is tracked on the 3D seismic prestack time migration data volume; The speed change difference is large and the speed change difference is not less than 1000m / s; The wave impedance interface is relatively strong and is an interface that has been accurately identified and judged by humans and can be continuously tracked.

3. The initial prestack migration velocity modeling method based on geological constraints according to claim 1, characterized in that: In step S3, the sonic curve or VSP logging curve is thinned out, and the thinned out points include points of the seismic reflection layer. Combined with the processing frequency, the velocity control points of each layer are obtained.

4. The initial prestack migration velocity modeling method based on geological constraints according to claim 3 is characterized in that: The processing frequency is selected as follows: the processing frequency for continental strata is 3.6-4.4 Hz, and the processing frequency for marine strata is 1.8-2.2 Hz.

5. The initial prestack migration velocity modeling method based on geological constraints according to claim 1, characterized in that: Step S4 includes: based on the velocity control points of each layer, performing velocity filling on the structural grid model in the time domain horizontally and vertically to obtain an initial velocity model.

6. The initial prestack migration velocity modeling method based on geological constraints according to any one of claims 1 to 5, characterized in that: In step S5, the constrained tomographic inversion near-surface velocity model is obtained by constrained tomographic inversion using surface VSP logging data; Combining the constrained tomographic inversion near-surface velocity model with the initial velocity model includes: replacing the near-surface velocity model with the constrained tomographic inversion near-surface velocity model, and continuing to use the initial velocity model for the deep velocity model.

7. The device of the initial prestack migration velocity modeling method based on geological constraints according to any one of claims 1 to 6, comprising a 3D seismic prestack time migration data volume acquisition module, a stratigraphic reflection horizon and fault acquisition module, a structural grid model and velocity control point acquisition module, an initial velocity model acquisition module, and an initial prestack depth migration velocity model acquisition module based on geological constraints; The 3D seismic pre-stack time migration data volume acquisition module is used to acquire the 3D seismic pre-stack time migration data volume of the work area based on the collected original seismic data; The stratigraphic reflection layer and fault acquisition module is used to interpret the 3D seismic profile layers and faults in the work area and obtain stratigraphic reflection layer and fault data of the velocity control layer of the 3D seismic prestack time migration data volume; The structural grid model and velocity control point acquisition module is used to establish a time-domain structural grid model based on the stratigraphic reflection horizons and faults of the velocity control layer of the 3D pre-stack time migration data volume, in accordance with the fault-cutting relationship and stratigraphic sequence; and is also used to determine the velocity control points of each layer according to the acoustic wave curve or VSP logging curve; The initial velocity model acquisition module is used to perform velocity filling on the structural grid model in the time domain based on the velocity control points of each layer to obtain an initial velocity model; The initial pre-stack depth migration velocity model acquisition module based on geological constraints is used to combine the constrained tomographic inversion near-surface velocity model with the initial velocity model to construct an initial pre-stack migration velocity model based on geological constraints.

8. A computer device comprising a processor and a computer program stored in a memory and executable on the processor, wherein: When the processor executes the computer program, the initial prestack migration velocity modeling method based on geological constraints according to any one of claims 1 to 6 is implemented.

9. A computer-readable storage medium, characterized in that The computer-readable storage medium stores a computer program for executing the initial prestack migration velocity modeling method based on geological constraints according to any one of claims 1 to 6.

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