Pre-stack inversion model fusion construction method and system based on synchronous extrusion wavelet transform

Abstract

The application discloses a method and system for constructing a pre-stack inversion model based on synchronous extrusion wavelet transform fusion, which comprises the following steps: obtaining a low-frequency velocity model in a time range of seismic data and a high-frequency velocity model above the top of a fracture-vug body; performing time-frequency analysis on the high-frequency model and the low-frequency model by using synchronous extrusion wavelet transform to obtain synchronous extrusion wavelet transform coefficients; analyzing the overlap based on the synchronous extrusion wavelet transform coefficients to obtain a spectrum at a certain moment; performing frequency fusion processing on all moments of a certain trace of data based on the spectrum at the certain moment to obtain a relatively wide time-frequency spectrum of the trace of data; obtaining the wide time-frequency spectrum of all seismic traces to obtain relatively wide frequency model data. The application performs time-frequency domain fusion based on synchronous extrusion wavelet transform on two kinds of background velocity fields, thereby constructing an inversion initial model for revealing deep information, and effectively solving the problems of insufficient drilling data of the fracture-vug body and the lower part and incomplete initial model information.

Description

Technical Field

[0001] This invention belongs to the technical field of pre-stack inversion initial model construction for ultra-deep carbonate reservoirs, and specifically relates to a method and system for fusion construction of pre-stack inversion models based on synchronous extrusion wavelet transform. Background Technology

[0002] In the process of advancing into deep and ultra-deep carbonate rocks, more and more oil and gas have been discovered, making it the most active region for ultra-deep oil and gas exploration and development globally. The Ordovician fractured-cavity reservoirs in the Tarim Basin are currently the most unique large-scale ultra-deep carbonate reservoirs discovered in China. Fault-controlled karst fractured-cavity reservoirs are extremely well-developed along the fault strike, and the fault-controlled karst elements are highly representative. Most wells in the Tarim Basin encounter karst when entering the Ordovician formation, resulting in significant losses such as blowouts and leaks. According to drilling design principles, drilling should ideally be completed up to target point B. If blowouts or leaks occur prematurely in the target section, plugging measures should be considered, and drilling through the fractured zone should be attempted as much as possible. If drilling complications arise during the process, potentially leading to uncontrollable well control risks, drilling can be completed ahead of schedule after integrated engineering and geological discussions. Logging instruments cannot penetrate the karst caves to measure deeper layers, resulting in scarce drilling data for deep carbonate rocks. However, for detailed characterization of hydrocarbon-bearing properties based on pre-stack inversion parameters, the lack of information on the interior of caverns makes the initial inversion model incomplete, which is even more detrimental to achieving detailed characterization of ultra-deep carbonate reservoirs. Summary of the Invention

[0003] The purpose of this invention is to provide a method and system for constructing a pre-stack inversion model based on synchronous extrusion wavelet transform, so as to solve the problem that the initial inversion model is incomplete due to the lack of information about the interior of the karst cave.

[0004] To achieve the above objectives, the present invention adopts the following technical solution:

[0005] In a first aspect, the present invention provides a method for constructing a fusion model based on pre-stack inversion model using synchronous squeezing wavelet transform, comprising:

[0006] Seismic data of pre-stack migration velocity field and information of the top of the fracture cavity were collected to obtain low-frequency velocity models within the seismic data time range and high-frequency velocity models at and above the top of the fracture cavity.

[0007] The synchronous squeezing wavelet transform coefficients were obtained by performing time-frequency analysis on the high-frequency and low-frequency models.

[0008] Based on the analysis of the overlap of synchronous squeezing wavelet transform coefficients, the spectrum at a certain moment is obtained;

[0009] Based on the spectrum at a certain moment, frequency fusion processing is performed on all moments of a certain channel of data to obtain the relatively wide time spectrum of that channel of data;

[0010] Broadband time-frequency spectra were obtained for all seismic traces to obtain relatively broadband model data.

[0011] Optionally, pre-stack migration velocity field seismic data and information on the top of the fracture cavity can be acquired to obtain low-frequency velocity models within the seismic data time range and high-frequency velocity models at and above the top of the fracture cavity, respectively:

[0012] The pre-stack migration velocity field is constructed based on seismic data and is used to establish a low-frequency velocity model within the time range of the seismic data. Information about the top of the fractured cavity was obtained based on well logging data, and an inverted high-frequency velocity model was constructed using the information about the top of the cavity.

[0013] Optionally, time-frequency analysis can be performed on the high-frequency and low-frequency models using synchronous squeezing wavelet transform to obtain the synchronous squeezing wavelet transform coefficients:

[0014] Using synchronous squeezing wavelet transform for high-frequency model V high (x, t) and low-frequency model V low Time-frequency analysis was performed on (x, t), and each data point V was analyzed. high (x i ,t) and V low (x i F is obtained from t) high (x i ,t,f) and F low (x i ,t,f); for data V high (x i For t), firstly, wavelet transform is performed using formula (1) to obtain WF. high (x i (a, b):

[0015]

[0016] in, It is the complex conjugate of the mother wavelet, where a and b are the scaling factor and translation factor, respectively. The scaling factor is frequency-dependent, and the translation factor is time-dependent. Based on this, the instantaneous frequency ω is calculated. s (x i (a, b):

[0017]

[0018] After obtaining the instantaneous frequency, the time spectrum of the wavelet transform is compressed in the frequency direction to obtain the synchronously compressed wavelet transform coefficients F. high (x i ,t,f), that is:

[0019]

[0020] For data V low (x, t) is also obtained according to formulas (1)-(3) to obtain F. low (x i ,t,f).

[0021] Optionally, the spectrum at a certain moment can be obtained by analyzing the overlap based on the synchronous squeezing wavelet transform coefficients:

[0022] For a certain time F of the i-th data high (x i , t i f) and F low (x i , t i f) Perform time-frequency analysis; F high (x i , t i f) and F low (x i , t i The overlap of f) includes two cases:

[0023] Where two spectra intersect, an inverted Halsey window is added at the intersection to smooth the values.

[0024] Where two spectra do not overlap, the two spectra are directly added together.

[0025] Optionally, in the first approach, where the two spectra intersect, an inverted Hamming window is added at the intersection to smooth the values, resulting in F. all (x i , t i f) represents the t of the i-th data. i The spectrum at time t, i.e.:

[0026]

[0027] Optionally, where two spectra do not intersect, the two spectra are directly added together to obtain F. all (x i , t i f), i.e., F all (x i , t i f) = F 1ow (x i , t i ,f)+F high (x i , t i f).

[0028] Optionally, based on the spectrum at a certain moment, frequency fusion processing is performed on all moments of a certain channel of data to obtain the relatively wide-band time spectrum of that channel of data:

[0029] By performing frequency fusion processing on all time points of the i-th channel data, the relative wide-band time spectrum F of the i-th channel data can be obtained. all (x i ,t,f), and then use synchronous squeezing wavelet inverse transform to F all (x i Transform t, f) into V all (x i ,t), that is:

[0030]

[0031] That is, relatively wideband seismic trace data.

[0032] Secondly, the present invention provides a system for constructing a fusion model based on pre-stack inversion model using synchronous squeeze wavelet transform, comprising:

[0033] The data acquisition module is used to acquire pre-stack migration velocity field seismic data and information on the top of the fracture cavity, and obtain the low-frequency velocity model within the seismic data time range and the high-frequency velocity model above the top of the fracture cavity, respectively.

[0034] The synchronous squeezing wavelet transform coefficient acquisition module is used to perform time-frequency analysis on high-frequency and low-frequency models using synchronous squeezing wavelet transform to obtain synchronous squeezing wavelet transform coefficients.

[0035] The frequency fusion processing module is used to analyze the overlap based on the synchronous squeezing wavelet transform coefficients to obtain the spectrum at a certain moment; based on the spectrum at a certain moment, frequency fusion processing is performed on all moments of a certain trace data to obtain the relative wideband time spectrum of that trace data; and the relative wideband time spectrum is obtained for all seismic traces to obtain the relative wideband model data.

[0036] Thirdly, the present invention provides a computer device, including a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor executes the computer program to implement the steps of a method for constructing a fusion model based on a synchronous squeeze wavelet transform pre-stack inversion model.

[0037] Fourthly, the present invention provides a computer-readable storage medium storing a computer program, which, when executed by a processor, implements the steps of a method for constructing a pre-stack inversion model fusion based on synchronous squeeze wavelet transform.

[0038] Compared with the prior art, the present invention has the following technical effects:

[0039] Pre-stack migration velocity fields are constructed based on seismic data, enabling the establishment of low-frequency background velocity fields within the seismic data time range. However, when well logging encounters Ordovician fracture-cavity bodies in the Tarim Basin, only information from the top of the fracture-cavity body is obtained. This information can be used to construct an inverted high-frequency velocity field. This invention fuses the velocity fields from both backgrounds in the time and frequency domain based on synchronous compression wavelet transform, thereby constructing an initial inversion model that reveals deep information. This effectively solves the problems of insufficient data on fracture-cavities and lower drilling sections, resulting in incomplete information in the initial model.

[0040] This invention can supplement fracture and cavity information when the logging curve lacks such information, but the inversion model requires such information, thereby constructing a relatively complete initial inversion model.

[0041] The synchronous squeezing wavelet transform is used to achieve frequency fusion based on time-frequency analysis. Compared with conventional frequency fusion based on Fourier transform, it has higher accuracy and precision.

[0042] By using the inverted Henin window to smoothly fuse the overlapping frequencies, frequency abrupt changes are avoided while maintaining effective frequency information. Compared with the conventional rectangular window, its spectrum is smoother, and the results obtained by mapping it to the time domain are more stable, which is also beneficial to the stability of subsequent inversion results. Attached Figure Description

[0043] Figure 1 This is a flowchart of the present invention.

[0044] Figure 2 This is a schematic diagram of frequency domain merging when the two models overlap in the frequency domain.

[0045] Figure 3 This is a schematic diagram of frequency domain merging when the two models do not overlap in the frequency domain.

[0046] Figure 4 This is a schematic diagram illustrating the technical principle.

[0047] Figure 5 It is a low-frequency model for the entire time period.

[0048] Figure 6 This is a high-frequency model of the top and above of the slit.

[0049] Figure 7 It is a relatively wideband model.

[0050] Figure 8 The high-frequency model inversion results for the top and above of the slit in the embodiment are shown.

[0051] Figure 9 The results are from the inversion of the relatively wideband model in the example. Detailed Implementation

[0052] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0053] In the description of this invention, it should be understood that the terms "comprising" and "including" indicate the presence of the described features, integrals, steps, operations, elements and / or components, but do not exclude the presence or addition of one or more other features, integrals, steps, operations, elements, components and / or collections thereof.

[0054] It should also be understood that the terminology used in this specification is for the purpose of describing particular embodiments only and is not intended to limit the invention. As used in this specification and the appended claims, the singular forms “a,” “an,” and “the” are intended to include the plural forms unless the context clearly indicates otherwise.

[0055] It should also be further understood that the term "and / or" as used in this specification and the appended claims refers to any combination and all possible combinations of one or more of the associated listed items, and includes such combinations. For example, A and / or B can represent three cases: A alone, A and B simultaneously, and B alone. Additionally, the character " / " in this invention generally indicates that the preceding and following objects have an "or" relationship.

[0056] It should be understood that although terms such as first, second, third, etc., may be used in the embodiments of the present invention to describe the preset range, these preset ranges should not be limited to these terms. These terms are only used to distinguish the preset ranges from one another. For example, without departing from the scope of the embodiments of the present invention, the first preset range may also be referred to as the second preset range, and similarly, the second preset range may also be referred to as the first preset range.

[0057] Depending on the context, the word "if" as used here can be interpreted as "when," "when," "in response to determination," or "in response to detection." Similarly, depending on the context, the phrase "if determination" or "if detection (of the stated condition or event)" can be interpreted as "when determination," "in response to determination," "when detection (of the stated condition or event)," or "in response to detection (of the stated condition or event)."

[0058] The accompanying drawings illustrate various structural schematic diagrams according to embodiments disclosed in this invention. These drawings are not to scale, and some details have been enlarged for clarity, and some details may have been omitted. The shapes of the various regions and layers shown in the drawings, as well as their relative sizes and positional relationships, are merely exemplary and may deviate from reality due to manufacturing tolerances or technical limitations. Furthermore, those skilled in the art can design regions / layers with different shapes, sizes, and relative positions as needed.

[0059] The present invention will be further described below with reference to the accompanying drawings:

[0060] Please see Figures 1 to 9 A method for constructing a fusion model based on synchronous squeezing wavelet transform pre-stack inversion model includes:

[0061] Seismic data of pre-stack migration velocity field and information of the top of the fracture cavity were collected to obtain low-frequency velocity models within the seismic data time range and high-frequency velocity models at and above the top of the fracture cavity.

[0062] The synchronous squeezing wavelet transform coefficients were obtained by performing time-frequency analysis on the high-frequency and low-frequency models.

[0063] Based on the analysis of the overlap of synchronous squeezing wavelet transform coefficients, the spectrum at a certain moment is obtained;

[0064] Based on the spectrum at a certain moment, frequency fusion processing is performed on all moments of a certain channel of data to obtain the relatively wide time spectrum of that channel of data;

[0065] Broadband time-frequency spectra were obtained for all seismic traces to obtain relatively broadband model data.

[0066] Pre-stack migration velocity fields are constructed based on seismic data, enabling the establishment of low-frequency background velocity fields within the seismic data time range. However, when well logging encounters Ordovician fracture-cavity bodies in the Tarim Basin, only information from the top of the fracture-cavity body is obtained. This information can be used to construct an inverted high-frequency velocity field. This invention fuses the velocity fields from both backgrounds in the time and frequency domain based on synchronous compression wavelet transform, thereby constructing an initial inversion model that reveals deep information. This effectively solves the problems of insufficient data on fracture-cavities and lower drilling sections, resulting in incomplete information in the initial model.

[0067] Specifically:

[0068] A frequency fusion technique based on time-frequency analysis is proposed. Synchronous squeezing wavelet transform is used to perform time-frequency analysis on low-frequency and high-frequency models, obtaining different time spectra of the same channel. Since there is partial overlap between frequencies, an inverted-Hay window is proposed for numerical fusion.

[0069] Specifically as follows:

[0070] Using synchronous squeezing wavelet transform for high-frequency model V high (x, t) and low-frequency model V low Time-frequency analysis was performed on (x, t), and each data point V was analyzed. high (x i ,t) and V low (x i F can be obtained from t) high (x i ,t,f) and F low (x i , t, f). For data V high (x i For t), firstly, wavelet transform is performed using formula (1) to obtain WF. high (x i (a, b):

[0071]

[0072] in, It is the complex conjugate of the mother wavelet, where a and b are the scaling factor and translation factor, respectively. The scaling factor is frequency-dependent, and the translation factor is time-dependent. Based on this, the instantaneous frequency ω is calculated. s (x i (a, b):

[0073]

[0074] After obtaining the instantaneous frequency, the time spectrum of the wavelet transform is compressed in the frequency direction to obtain the synchronously compressed wavelet transform coefficients F. high (x i ,t,f), that is:

[0075]

[0076] For data V low (x, t) is also obtained according to formulas (1)-(3) to obtain F. low (x i ,t,f).

[0077] For a certain time F of the i-th data high (x i , t i f) and F low (x i , t i ,f) to conduct a detailed analysis. high (x i , t i f) and F low (x i , t iThere are two possible overlaps in f). The first is as follows: Figure 1 The image shows two blue broken lines representing the shapes of two spectra. Where the two spectra intersect, an inverted Halite window is added at the intersection to smooth the values ​​and avoid abrupt frequency changes, thus obtaining F. all (x i , t i f) represents the t of the i-th data. i The spectrum at time t, i.e.:

[0078]

[0079] The second scenario is when the two spectra differ slightly, such as... Figure 2 As shown, the two spectra can be directly added together to obtain F. all (x i , t i f), i.e., F all (x i , t i f) = F low (x i , t i ,f)+F high (x i , t i f)

[0080] By performing frequency fusion processing on all time points of the i-th channel data, the relative wide-band time spectrum F of the i-th channel data can be obtained. all (x i (t, f). Then, using synchronous squeezing wavelet inverse transform, F all (x i Transform t, f) into V all (x i ,t), that is:

[0081]

[0082] That is, relatively wideband seismic trace data.

[0083] By processing all seismic traces in the same way, relatively broadband model data can be obtained.

[0084] This invention can supplement fracture and cavity information when the logging curve lacks such information, but the inversion model requires such information, thereby constructing a relatively complete initial inversion model.

[0085] The synchronous squeezing wavelet transform is used to achieve frequency fusion based on time-frequency analysis. Compared with conventional frequency fusion based on Fourier transform, it has higher accuracy and precision.

[0086] By using the inverted Henin window to smoothly fuse the overlapping frequencies, frequency abrupt changes are avoided while maintaining effective frequency information. Compared with the conventional rectangular window, its spectrum is smoother, and the results obtained by mapping it to the time domain are more stable, which is also beneficial to the stability of subsequent inversion results.

[0087] Example:

[0088] Using the Yueman 22 well in the Yueman West work area as an example, the following is an illustration: First, a low-frequency velocity model for the entire time period is constructed using migration velocity, as shown below. Figure 5 As shown, its frequency range is 1-12Hz. A high-frequency velocity model was then obtained by interpolation using well logging data, as shown below. Figure 6 As shown, its frequency range is 1-70Hz. Since the two models overlap in the frequency domain, the one shown is used instead. Figure 2 The frequency domain merging strategy is shown.

[0089] Synchronous squeezing wavelet transforms were performed on both the low-frequency and high-frequency velocity models across the entire time period, and frequency merging was performed using Equation 4, where f1 is selected as 8Hz and f2 as 16Hz. The frequency-merged data volume was then subjected to an inverse synchronous squeezing wavelet transform to obtain the relatively broadband model of this patented method, as shown below. Figure 7 As shown.

[0090] Figure 8 To utilize the fused relatively wideband model for pre-stack inversion of longitudinal wave impedance,

[0091] Figure 9 To utilize the high-frequency model above and above the slot to invert the longitudinal wave impedance before stacking.

[0092] Compared to the inversion results obtained from the high-frequency model, the inversion results from the broadband model show a more complete fracture morphology and richer deep information.

[0093] In another embodiment of the present invention, a system for constructing a fusion model based on a pre-stack inversion model using synchronous squeeze wavelet transform is provided. This system can be used to implement the above-mentioned method for constructing a fusion model based on a pre-stack inversion model using synchronous squeeze wavelet transform. Specifically, the system includes:

[0094] The data acquisition module is used to acquire pre-stack migration velocity field seismic data and information on the top of the fracture cavity, and obtain the low-frequency velocity model within the seismic data time range and the high-frequency velocity model above the top of the fracture cavity, respectively.

[0095] The synchronous squeezing wavelet transform coefficient acquisition module is used to perform time-frequency analysis on high-frequency and low-frequency models using synchronous squeezing wavelet transform to obtain synchronous squeezing wavelet transform coefficients.

[0096] The frequency fusion processing module is used to analyze the overlap based on the synchronous squeezing wavelet transform coefficients to obtain the spectrum at a certain moment; based on the spectrum at a certain moment, frequency fusion processing is performed on all moments of a certain trace data to obtain the relative wideband time spectrum of that trace data; and the relative wideband time spectrum is obtained for all seismic traces to obtain the relative wideband model data.

[0097] This invention uses two background velocity fields to perform time-frequency domain fusion based on synchronous squeezing wavelet transform, thereby constructing an inversion initial model that reveals deep information, effectively solving the problems of insufficient data on fractured bodies and lower drilling, and incomplete information in the initial model.

[0098] The module division in this embodiment of the invention is illustrative and represents only one logical functional division. In actual implementation, other division methods may be used. Furthermore, the functional modules in the various embodiments of the invention can be integrated into a single processor, exist as separate physical entities, or be integrated into a single module. The integrated modules described above can be implemented in hardware or as software functional modules.

[0099] In another embodiment of the present invention, a computer device is provided, comprising a processor and a memory. The memory stores a computer program, which includes program instructions. The processor executes the program instructions stored in the computer storage medium. The processor may be a Central Processing Unit (CPU), or other general-purpose processors, digital signal processors (DSPs), application-specific integrated circuits (ASICs), field-programmable gate arrays (FPGAs), or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, etc. It is the computing and control core of the terminal, suitable for implementing one or more instructions, specifically suitable for loading and executing one or more instructions in the computer storage medium to achieve a corresponding method flow or corresponding function. The processor described in this embodiment of the present invention can be used for the operation of a method for constructing a fusion model based on a synchronous squeeze wavelet transform pre-stack inversion model.

[0100] In another embodiment of the present invention, a storage medium is provided, specifically a computer-readable storage medium (Memory), which is a memory device in a computer device used to store programs and data. It is understood that the computer-readable storage medium here can include both the built-in storage medium in the computer device and extended storage media supported by the computer device. The computer-readable storage medium provides storage space that stores the terminal's operating system. Furthermore, the storage space also stores one or more instructions suitable for loading and execution by a processor. These instructions can be one or more computer programs (including program code). It should be noted that the computer-readable storage medium here can be high-speed RAM or non-volatile memory, such as at least one disk storage device. The processor can load and execute one or more instructions stored in the computer-readable storage medium to implement the corresponding steps of the pre-stack inversion model fusion construction method based on synchronous squeeze wavelet transform in the above embodiments.

[0101] Those skilled in the art will understand that embodiments of the present invention can be provided as methods, systems, or computer program products. Therefore, the present invention can take the form of a completely hardware embodiment, a completely software embodiment, or an embodiment combining software and hardware aspects. Furthermore, the present invention can take the form of a computer program product embodied on one or more computer-usable storage media (including, but not limited to, disk storage, CD-ROM, optical storage, etc.) containing computer-usable program code.

[0102] This invention is described with reference to flowchart illustrations and / or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of the invention. It will be understood that each block of the flowchart illustrations and / or block diagrams, and combinations of blocks in the flowchart illustrations and / or block diagrams, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, special-purpose computer, embedded processor, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, generate instructions for implementing the flowchart illustrations and / or block diagrams. Figure 1 One or more processes and / or boxes Figure 1 A device that provides the functions specified in one or more boxes.

[0103] These computer program instructions may also be stored in a computer-readable storage medium that can direct a computer or other programmable data processing device to function in a particular manner, such that the instructions stored in the computer-readable storage medium produce an article of manufacture including instruction means, which are implemented in a process Figure 1One or more processes and / or boxes Figure 1 The function specified in one or more boxes.

[0104] These computer program instructions may also be loaded onto a computer or other programmable data processing equipment to cause a series of operational steps to be performed on the computer or other programmable equipment to produce a computer-implemented process, thereby providing instructions that execute on the computer or other programmable equipment for implementing the process. Figure 1 One or more processes and / or boxes Figure 1 The steps of the function specified in one or more boxes.

[0105] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and not to limit it. Although the present invention has been described in detail with reference to the above embodiments, those skilled in the art should understand that modifications or equivalent substitutions can still be made to the specific implementation of the present invention. Any modifications or equivalent substitutions that do not depart from the spirit and scope of the present invention should be covered within the scope of protection of the claims of the present invention.

Claims

1. A method for constructing a pre-stack inversion model based on synchronous extrusion wavelet transform fusion, characterized in that, The method comprises the following steps: Collecting prestack migration velocity field seismic data and fracture-vug body top information, and obtaining a low-frequency velocity model within a seismic data time range and a high-frequency velocity model above the fracture-vug body top, respectively; Performing time-frequency analysis on the high-frequency model and the low-frequency model by using synchronous extrusion wavelet transform to obtain synchronous extrusion wavelet transform coefficients; Analyzing overlap conditions based on the synchronous extrusion wavelet transform coefficients to obtain a frequency spectrum at a certain moment; Performing frequency fusion processing on all moments of a certain seismic trace based on the frequency spectrum at the certain moment to obtain a relatively wide time-frequency spectrum of the seismic trace; Obtaining a wide time-frequency spectrum of all seismic traces to obtain a relatively wide frequency model data; Collecting prestack migration velocity field seismic data and fracture-vug body top information, and obtaining a low-frequency velocity model within a seismic data time range and a high-frequency velocity model above the fracture-vug body top, respectively: The prestack migration velocity field is constructed based on seismic data, and is used to establish a low-frequency velocity model within a seismic data time range; the fracture-vug body top information is obtained based on logging data, and is used to construct an inversion high-frequency velocity model.

2. The method according to claim 1, characterized in that, Performing time-frequency analysis on the high-frequency model and the low-frequency model by using synchronous extrusion wavelet transform to obtain synchronous extrusion wavelet transform coefficients: Using synchronous extrusion wavelet transform to high frequency model and low frequency model Time-frequency analysis is carried out on each data and , and and are obtained; for data , first wavelet transform is carried out using formula (1) to obtain : （1） wherein is the complex conjugate of the mother wavelet, and are the scale factor and the shift factor, respectively, the scale factor being related to the frequency and the shift factor being related to the time; on this basis, the instantaneous frequency is calculated （2） After the instantaneous frequency is obtained, the time-frequency spectrum of the wavelet transform is squeezed in the frequency direction to obtain synchronous squeezed wavelet transform coefficients That is: （3） For data Also according to equations (1) - (3) .

3. The method according to claim 2, characterized in that, Analyzing overlap conditions based on the synchronous extrusion wavelet transform coefficients to obtain a frequency spectrum at a certain moment: the time of the ith channel data and time-frequency analysis is performed; and The overlap of the two includes two kinds: Where the two frequency spectrums intersect, a reverse Hanning window is added at the intersection for smooth value taking; Where the two frequency spectrums do not intersect, the two frequency spectrums are directly added.

4. The method according to claim 3, characterized in that, The first two frequency spectrum has the intersection, in the intersection adds the inverted Hanning window to carry on the smooth value, obtains The frequency spectrum of the i-th data at the time t, that is: The frequency spectrum of the i-th data at the time t, that is: （4）。 5. The method according to claim 3, characterized in that, Two frequency spectrums have no intersection, and the two frequency spectrums are directly added as That is .

6. The method according to claim 2, characterized in that, Performing frequency fusion processing on all moments of a certain seismic trace based on the frequency spectrum at the certain moment to obtain a relatively wide time-frequency spectrum of the seismic trace: The frequency fusion processing is performed on all time points of the ith data, and the relative wide-band spectrum of the ith data is obtained The inverse transform of the synchronous extrusion wavelet is used again to transform into that is: （5） That is, a relatively wide frequency band seismic trace data.

7. A system for fusing pre-stack inversion models based on synchronous extruded wavelet transform, characterized in that, The method comprises the following steps: A data acquisition module is configured to collect prestack migration velocity field seismic data and fracture-vug body top information, and obtain a low-frequency velocity model within a seismic data time range and a high-frequency velocity model above the fracture-vug body top, respectively; A synchronous extrusion wavelet transform coefficient acquisition module is configured to perform time-frequency analysis on the high-frequency model and the low-frequency model by using synchronous extrusion wavelet transform to obtain synchronous extrusion wavelet transform coefficients; A frequency fusion processing module is configured to analyze overlap conditions based on the synchronous extrusion wavelet transform coefficients to obtain a frequency spectrum at a certain moment; perform frequency fusion processing on all moments of a certain seismic trace based on the frequency spectrum at the certain moment to obtain a relatively wide time-frequency spectrum of the seismic trace; and obtain a wide time-frequency spectrum of all seismic traces to obtain a relatively wide frequency model data. Collecting prestack migration velocity field seismic data and fracture-vug body top information, and obtaining a low-frequency velocity model within a seismic data time range and a high-frequency velocity model above the fracture-vug body top, respectively: The prestack migration velocity field is constructed based on seismic data, and is used to establish a low-frequency velocity model within a seismic data time range; the fracture-vug body top information is obtained based on logging data, and is used to construct an inversion high-frequency velocity model.

8. A computer device comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, characterized in that, The processor implements the steps of the method for constructing a prestack inversion model based on synchronous extrusion wavelet transform fusion according to any one of claims 1 to 6 when executing the computer program.

9. A computer-readable storage medium storing a computer program, the computer program comprising instructions that, when executed by a computer, cause the computer to perform the method of any one of claims 1 to 8. The computer program is executed by a processor to implement the steps of the method for constructing a pre-stack inversion model based on synchronous extrusion wavelet transform fusion according to any one of claims 1 to 6.

Images