PP-wave VTI medium dynamic correction method and device based on segmented velocity modeling

Abstract

The present invention discloses a dynamic correction method and device for PP wave VTI media based on segmented velocity modeling. The method includes: acquiring seismic data of a target transversely isotropic medium to be dynamically corrected, and then organizing to obtain a target gather; performing velocity analysis on the target gather, and performing velocity and time information conversion to obtain depth information corresponding to each seismic data in the target gather; obtaining a deviation-depth ratio based on the ratio of the offset to the depth information; cutting the target gather based on the deviation-depth ratio to obtain gather segments; performing velocity analysis on the gather segments to obtain velocity information; determining a deviation-depth ratio increment corresponding to each seismic data in the gather segments based on a preset first deviation-depth ratio threshold value, and further obtaining a P-wave anisotropic velocity; and then obtaining a target travel time, and performing dynamic correction on the target transversely isotropic medium according to the target travel time. The present invention can accurately perform dynamic correction for PP wave VTI media and can be widely applied to the field of data processing technology.

Description

Technical Field

[0001] The present invention relates to the technical field of data processing, and in particular, to a PP-wave VTI medium NMO method and device based on segmented velocity modeling. Background Art

[0002] The seismic data NMO technology is an essential technology for seismic exploration, which is used to correct the time difference generated by the same reflection point underground due to the change of offset. However, with the development of seismic processing technology and the need for high-precision seismic exploration, the conventional NMO technology cannot correct the non-hyperbolic time difference caused by anisotropy, and the NMO effect directly affects the superposition imaging quality. At present, the anisotropic traveltime curve fitting formula can only flatten the seismic data in-phase axis within a certain offset range, but cannot correct the in-phase axis of medium and far offsets. Therefore, scientists have introduced weak anisotropic parameters and continuously improved the NMO formula to better fit the traveltime curve and achieve a better NMO effect. However, so far, the offset range that the NMO formula can fit is still limited. After exceeding a certain offset, a large residual correction amount will be generated, seriously affecting the data superposition quality. Summary of the Invention

[0003] The present invention aims to solve the problems of related technology limitations at least to a certain extent. For this purpose, the present invention provides a PP-wave VTI medium NMO method and device based on segmented velocity modeling, which can accurately perform PP-wave VTI medium NMO based on segmented velocity modeling.

[0004] On the one hand, an embodiment of the present invention provides a PP-wave VTI medium NMO method based on segmented velocity modeling, including:

[0005] Obtain seismic data of a target transversely isotropic medium to be NMO, and then organize it to obtain a target gather; the seismic data is obtained based on PP-waves;

[0006] Perform velocity analysis on the target gather to obtain an initial velocity model in the time domain; convert the velocity and time information in the initial velocity model to obtain the depth information corresponding to each seismic data in the target gather;

[0007] Based on the ratio of the offset corresponding to the seismic data to the depth information, obtain the offset-depth ratio of each seismic data; wherein, the offset represents the distance between the seismic source generating the seismic data and the geophone receiving the seismic data;

[0008] Cut the target gather based on the offset-depth ratio to obtain a preset number of gather segments; the gather segments include near-offset gather, medium-offset gather, and far-offset gather;

[0009] Perform velocity analysis on the gather segments to obtain the velocity information corresponding to each seismic data in the gather segments;

[0010] Determine the depth ratio increment corresponding to each seismic data in all trace gather segments based on a preset first depth ratio threshold value;

[0011] Based on the depth ratio increment and in combination with a preset P-wave anisotropic parameter, obtain the P-wave anisotropic velocity at the offset corresponding to the seismic data corresponding to the depth ratio increment;

[0012] Obtain the target travel time based on the P-wave anisotropic velocity, and perform NMO correction on the target transversely isotropic medium according to the target travel time.

[0013] Optionally, obtain the seismic data of the target transversely isotropic medium to be NMO corrected, and then organize to obtain a target trace gather, including:

[0014] Obtain the seismic trace of each geophone set in the target transversely isotropic medium to be NMO corrected;

[0015] Arrange all seismic traces in ascending order of offset to obtain a common midpoint trace gather.

[0016] Optionally, based on the depth ratio, cut the target trace gather to obtain a preset number of trace gather segments, including:

[0017] Divide the seismic data in the target trace gather with a depth ratio less than or equal to the first depth ratio threshold value into a near-offset trace gather;

[0018] Divide the seismic data in the target trace gather with a depth ratio greater than the first depth ratio threshold value and less than or equal to the second depth ratio threshold value into a mid-offset trace gather;

[0019] Divide the seismic data in the target trace gather with a depth ratio greater than the second depth ratio threshold value into a far-offset trace gather.

[0020] Optionally, determine the depth ratio increment corresponding to each seismic data in all trace gather segments based on a preset first depth ratio threshold value, including:

[0021] Determine the depth ratio increment corresponding to each seismic data according to the difference between the depth ratio corresponding to each seismic data in the mid-offset trace gather and the far-offset trace gather and the first depth ratio threshold value;

[0022] Among them, the depth ratio increment corresponding to each seismic data in the near-offset trace gather is determined to be 0.

[0023] Optionally, the P-wave anisotropic parameter includes a mid-offset parameter and a far-offset parameter; based on the depth ratio increment and in combination with a preset P-wave anisotropic parameter, obtain the P-wave anisotropic velocity at the offset corresponding to the seismic data corresponding to the depth ratio increment, including:

[0024] Preset the calibration velocity for velocity information based on trace segmenting; the calibration velocity includes near-offset velocity, mid-offset velocity, and far-offset velocity; among them, the P-wave anisotropic parameter is set based on the calibration velocity;

[0025] When the seismic data corresponding to the offset-depth ratio increment belongs to the mid-offset trace gather, perform a first increment adjustment on the near-offset velocity based on the product of the mid-offset parameter and the offset-depth ratio increment to obtain the P-wave anisotropic velocity at the offset corresponding to the seismic data;

[0026] When the seismic data corresponding to the offset-depth ratio increment belongs to the far-offset trace gather, perform a second increment adjustment on the near-offset velocity based on the product of the far-offset parameter and the offset-depth ratio increment to obtain the P-wave anisotropic velocity at the offset corresponding to the seismic data.

[0027] Optionally, the method further includes:

[0028] Set the P-wave anisotropic parameter based on the calibration velocity, in combination with the range interval values of the offset-depth ratios corresponding to the mid-offset trace gather and the far-offset trace gather;

[0029] Among them, the expression of the mid-offset parameter is:

[0030]

[0031] In the formula, g p_mid represents the mid-offset parameter; v p_mid represents the mid-offset velocity; v p_near represents the near-offset velocity; rod mid represents the range interval value of the offset-depth ratio corresponding to the mid-offset trace gather;

[0032] The expression of the far-offset parameter is:

[0033]

[0034] In the formula, g p_far represents the far-offset parameter; v p_far represents the far-offset velocity; rod far represents the range interval value of the offset-depth ratio corresponding to the far-offset trace gather.

[0035] Optionally, obtain the target travel time based on the P-wave anisotropic velocity, and perform NMO correction on the target transversely isotropic medium according to the target travel time, including:

[0036] Obtain the reflection time of the target reflection interface in the target transversely isotropic medium at zero offset;

[0037] Based on the product of the P-wave anisotropic velocity and half of the reflection time, obtain the equivalent depth of the target reflection interface;

[0038] The target travel time is obtained based on the equivalent depth, the P-wave anisotropic velocity, and the corresponding offset through a preset NMO formula;

[0039] Among them, the expression of the preset NMO formula is:

[0040]

[0041] In the formula, t(x) represents the target travel time; x s represents half of the offset corresponding to the P-wave anisotropic velocity; z eff represents; represents the equivalent depth; v p(x) represents the P-wave anisotropic velocity;

[0042] NMO correction is performed on the target transversely isotropic medium according to the difference between the target travel time and half of the reflection time.

[0043] On the other hand, an embodiment of the present invention provides a PP-wave VTI medium NMO correction device based on segmented velocity modeling, including:

[0044] The first module is used to obtain the seismic data of the target transversely isotropic medium to be NMO corrected, and then organize it to obtain the target gather; the seismic data is based on PP waves;

[0045] The second module is used to perform velocity analysis on the target gather to obtain an initial velocity model in the time domain; based on the velocity and time information in the initial velocity model, the depth information corresponding to each seismic data in the target gather is converted;

[0046] The third module is used to obtain the depth-offset ratio of each seismic data based on the ratio of the offset corresponding to the seismic data to the depth information; among them, the offset represents the distance between the seismic source generating the seismic data and the geophone receiving the seismic data;

[0047] The fourth module is used to cut the target gather based on the depth-offset ratio to obtain a preset number of gather segments; the gather segments include near-offset gathers, mid-offset gathers, and far-offset gathers;

[0048] The fifth module is used to perform velocity analysis on the gather segments to obtain the velocity information corresponding to each seismic data in the gather segments;

[0049] The sixth module is used to determine the depth-offset ratio increment corresponding to each seismic data in all gather segments based on a preset first depth-offset ratio threshold value;

[0050] The seventh module is used to obtain the P-wave anisotropic velocity at the offset corresponding to the seismic data corresponding to the depth-offset ratio increment based on the depth-offset ratio increment and a preset P-wave anisotropic parameter;

[0051] The eighth module is used to obtain the target travel time based on the longitudinal wave anisotropic velocity and perform dynamic correction on the target transversely isotropic medium according to the target travel time.

[0052] Optionally, the device further includes:

[0053] The ninth module is used to set the longitudinal wave anisotropic parameter based on the corrected velocity in combination with the range interval value of the offset-depth ratio corresponding to the medium-offset gather and the far-offset gather;

[0054] Wherein, the expression of the medium-offset parameter is:

[0055]

[0056] In the formula, g p_mid represents the medium-offset parameter; v p_mid represents the medium-offset velocity; v p_near represents the near-offset velocity; rod mid represents the range interval value of the offset-depth ratio corresponding to the medium-offset gather;

[0057] The expression of the far-offset parameter is:

[0058]

[0059] In the formula, g p_far represents the far-offset parameter; v p_far represents the far-offset velocity; rod far represents the range interval value of the offset-depth ratio corresponding to the far-offset gather.

[0060] On the other hand, an embodiment of the present invention provides an electronic device, including: a processor and a memory; the memory is used to store a program; the processor executes the program to implement the above-mentioned dynamic correction method for PP wave VTI medium based on segmented velocity modeling.

[0061] On the other hand, an embodiment of the present invention provides a computer storage medium, in which a program executable by a processor is stored, and the program executable by the processor is used to implement the above-mentioned dynamic correction method for PP wave VTI medium based on segmented velocity modeling when executed by the processor.

[0062] In an embodiment of the present invention, seismic data of a target transversely isotropic medium to be kinematically corrected is acquired, and then a target gather is sorted out; the seismic data is obtained based on PP waves; velocity analysis is performed on the target gather to obtain an initial velocity model in the time domain; depth information corresponding to each seismic data in the target gather is obtained by converting based on the velocity and time information in the initial velocity model; based on the ratio of the offset corresponding to the seismic data to the depth information, the depth-offset ratio of each seismic data is obtained; wherein, the offset represents the distance between the seismic source generating the seismic data and the geophone receiving the seismic data; the target gather is segmented based on the depth-offset ratio to obtain a preset number of gather segments; the gather segments include a near-offset gather, a mid-offset gather, and a far-offset gather; velocity analysis is performed on the gather segments to obtain velocity information corresponding to each seismic data in the gather segments; based on a preset first depth-offset ratio threshold, the depth-offset ratio increment corresponding to each seismic data in all gather segments is determined; based on the depth-offset ratio increment and a preset P-wave anisotropy parameter, the P-wave anisotropic velocity at the offset corresponding to the seismic data corresponding to the depth-offset ratio increment is obtained; based on the P-wave anisotropic velocity, a target travel time is obtained, and kinematic correction is performed on the target transversely isotropic medium according to the target travel time. In the embodiment of the present invention, by using the ratio of the offset to the depth information, velocity analysis modeling is realized through the depth-offset ratio, and then VTI medium kinematic correction is gradually realized based on the depth-offset ratio increment; the embodiment of the present invention can accurately perform PP-wave VTI medium kinematic correction based on segmented velocity modeling. Description of the Drawings

[0063] The drawings are used to provide a further understanding of the technical solutions of the present invention, and constitute a part of the specification. Together with the embodiments of the present invention, they are used to explain the technical solutions of the present invention, and do not constitute a limitation to the technical solutions of the present invention.

[0064] Figure 1 It is a schematic diagram of an implementation environment for a method for performing PP-wave VTI medium kinematic correction based on segmented velocity modeling provided by an embodiment of the present invention;

[0065] Figure 2 It is a flowchart of a method for performing PP-wave VTI medium kinematic correction based on segmented velocity modeling provided by an embodiment of the present invention;

[0066] Figure 3 It is a schematic diagram of a CMP gather provided by an embodiment of the present invention;

[0067] Figure 4 It is a schematic diagram of a schematic diagram of a seismic event provided by an embodiment of the present invention;

[0068] Figure 5 It is a schematic diagram of the splitting effect of a gather provided by an embodiment of the present invention;

[0069] Figure 6Schematic diagram of the overall process of PP-wave VTI medium dynamic correction based on segmented velocity modeling provided by an embodiment of the present invention;

[0070] Figure 7 Schematic diagram of the medium offset velocity analysis effect provided by an embodiment of the present invention;

[0071] Figure 8 Schematic diagram of the PP-wave dynamic correction effect of VTI medium provided by an embodiment of the present invention;

[0072] Figure 9 Schematic diagram of the structure of a PP-wave VTI medium dynamic correction device based on segmented velocity modeling provided by an embodiment of the present invention;

[0073] Figure 10 Schematic diagram of the structure of an electronic device provided by an embodiment of the present invention. Detailed implementation manners

[0074] In order to make the objectives, technical solutions and advantages of the present invention clearer, the present invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention.

[0075] It should be noted that although functional module division is performed in the system schematic diagram and the logical sequence is shown in the flowchart, in some cases, the steps shown or described may be executed in a different module division in the system or a different sequence in the flowchart. Terms such as "first / S100" and "second / S200" in the description, claims and the above drawings are used to distinguish similar objects and do not necessarily need to describe a specific order or sequence.

[0076] Referring to "embodiment" herein means that a specific feature, structure or characteristic described in connection with the embodiment may be included in at least one embodiment of the present invention. The phrase appears in various positions in the specification and does not necessarily refer to the same embodiment, nor is it an independent or alternative embodiment mutually exclusive with other embodiments. Those skilled in the art will explicitly and implicitly understand that the embodiments described herein can be combined with other embodiments.

[0077] It can be understood that the PP-wave VTI medium dynamic correction method based on segmented velocity modeling provided by the embodiments of the present invention can be applied to any computer device with data processing and computing capabilities, and this computer device can be various types of terminals or servers. When the computer device in the embodiment is a server, the server is an independent physical server, or a server cluster or distributed system composed of multiple physical servers, or a cloud server that provides basic cloud computing services such as cloud services, cloud databases, cloud computing, cloud functions, cloud storage, network services, cloud communications, middleware services, domain name services, security services, CDN (Content Delivery Network), and big data and artificial intelligence platforms. Optionally, the terminal is a smart phone, a tablet computer, a laptop computer, a desktop computer, etc., but is not limited thereto.

[0078] For the convenience of understanding the technical solutions of the present invention, first, the technical feature proper nouns that may appear in the embodiments of the present invention are explained:

[0079] The reception record of a single geophone is called a seismic trace. A collection of multiple seismic traces is simply called a trace gather.

[0080] VTI medium is short for transverse isotropy with a vertical axis of symmetry (i.e., VTI) medium.

[0081] As Figure 1 shown, it is a schematic diagram of an implementation environment provided by the embodiments of the invention. Referring to Figure 1 , this implementation environment includes at least one terminal 102 and a server 101. The terminal 102 and the server 101 can be network-connected wirelessly or wiredly to complete data transmission and exchange.

[0082] The server 101 can be an independent physical server, or a server cluster or distributed system composed of multiple physical servers, or a cloud server that provides basic cloud computing services such as cloud services, cloud databases, cloud computing, cloud functions, cloud storage, network services, cloud communications, middleware services, domain name services, security services, CDN (Content Delivery Network), and big data and artificial intelligence platforms.

[0083] In addition, the server 101 can also be a node server in a blockchain network. Among them, blockchain is a new application mode of computer technologies such as distributed data storage, peer-to-peer transmission, consensus mechanism, and encryption algorithms.

[0084] The terminal 102 may be a smart phone, a tablet computer, a laptop computer, a desktop computer, a smart speaker, a smart watch, etc., but is not limited thereto. The terminal 102 and the server 101 may be directly or indirectly connected through wired or wireless communication means, and the embodiments of the present invention do not limit this here.

[0085] Exemplarily based on Figure 1 the implementation environment shown, the embodiments of the present invention provide a PP-wave VTI medium dynamic correction method based on segmented velocity modeling. Taking the application of the PP-wave VTI medium dynamic correction method based on segmented velocity modeling to the server 101 as an example for description, it can be understood that the PP-wave VTI medium dynamic correction method based on segmented velocity modeling can also be applied to the terminal 102.

[0086] Refer to Figure 2 , Figure 2 is a flowchart of the PP-wave VTI medium dynamic correction method based on segmented velocity modeling applied to the server provided by the embodiments of the present invention. The execution subject of the PP-wave VTI medium dynamic correction method based on segmented velocity modeling may be any of the foregoing computer devices (including servers or terminals). Refer to Figure 2 and the method includes the following steps:

[0087] S100. Obtain seismic data of the target transversely isotropic medium to be dynamically corrected, and then organize to obtain a target gather;

[0088] It should be noted that the seismic data is obtained based on PP waves; in some embodiments, step S100 may include: obtaining seismic traces of each geophone set in the target transversely isotropic medium to be dynamically corrected; arranging all seismic traces in ascending order of offset to obtain a common midpoint gather.

[0089] Exemplarily, in some specific embodiments, the specific parameters of the gather: When processing PP-wave (the concept of PP-wave is that the wave excited by the seismic source is a longitudinal wave (P-wave), and after reflection, it remains a longitudinal wave (P-wave)) seismic data, the commonly used gathers are shot gathers and CMP (Common Middle Point) gathers. The two are different selection and arrangement methods based on the same data. First, let's talk about the shot gather. The shot gather is the original data selection and arrangement method obtained in the embodiments of the present invention. It refers to the set of seismic traces of the same seismic source signal received by multiple orderly arranged geophones. Here, it is mentioned that the arrangement of the geophones is orderly, and their spacing is generally a fixed value. The embodiments of the present invention call this spacing value the trace interval. Generally speaking, the trace interval is a multiple of 1.25m, and common ones are 2.5m, 5m, 6.25m, 12.5m, etc. The arrangement of the seismic sources is generally also along the direction of the geophone arrangement, and its spacing is also a fixed value. The embodiments of the present invention call it the shot interval. The shot interval is generally 2 times the trace interval. Usually, a geophone array can be several kilometers long. Taking an 8-kilometer geophone array as an example, assuming its trace interval is 12.5m, then a shot gather contains 648 seismic traces. Assuming the designed length of the observation line in the embodiments of the present invention is 100 kilometers, a shot interval of 25m will generate 4000 shot gathers. After reselecting and arranging these shot gathers, because the reflection of the PP-wave is symmetric, it can be reselected using CMP gathers. Theoretically, the spacing between adjacent CMPs is 1 / 2 of the trace interval, the number of seismic traces contained in each gather is 1 / 4 of that of the shot gather, and the total number of gathers is 2 times that of the shot gather. Taking the above parameters as an example, that is, for a 100-kilometer survey line, 8000 CMP gathers will be generated. In the same CMP gather, they are arranged in ascending order of offset (the distance between the shot point and the geophone point), as Figure 3 shown, which is a schematic diagram of the CMP gather.

[0090] S200. Perform velocity analysis on the target gather to obtain an initial velocity model in the time domain; based on the velocity and time information in the initial velocity model, convert to obtain the depth information corresponding to each seismic data in the target gather;

[0091] First of all, it should be noted that when seismic waves propagate downward, due to different media, their propagation speeds will change with space. Just like the propagation speed of seismic waves in air is 340m / s, while in water it can reach 1500m / s, but these are not completely accurate values. Because of differences in air humidity, temperature, and water temperature, salinity, and stratification characteristics, etc., the seismic wave speed will show spatial changes. The seismic traces recorded in the embodiments of the present invention are 1-dimensional time records and cannot obtain the spatial changes in speed. After rising to 2 dimensions, that is, the CMP gather, as Figure 4As shown, the time difference of the reflected event axis (i.e., the response of the reflected wave of the same underground interface at different geophone points) can be used to analyze the velocity change (here the change is in the time domain, not the spatial domain). Through the original velocity analysis, an original velocity model can be established.

[0092] Exemplarily, in some specific embodiments, through conventional velocity analysis, a preliminary seismic wave propagation velocity model can be obtained. This velocity model is in the time domain, and then the depth can be converted through velocity and time. Among them, the velocity analysis can adopt the conventional velocity analysis method for seismic wave data, which is not limited by the embodiments of the present invention and will not be elaborated here.

[0093] S300. Obtain the offset-depth ratio of each seismic data based on the ratio of the offset corresponding to the seismic data to the depth information;

[0094] Among them, the offset represents the distance between the seismic source generating the seismic data and the geophone receiving the seismic data;

[0095] Exemplarily, in some specific embodiments, the segmented velocity modeling of the embodiments of the present invention is divided according to the offset-depth ratio. The definition of the offset-depth ratio (ord) is the ratio of the offset to the depth (the calculation formula of the depth is the same as formula (2) later, but the velocity used is the velocity obtained from the original analysis).

[0096] S400. Cut the target gather based on the offset-depth ratio to obtain a preset number of gather segments;

[0097] Among them, the gather segments include near-offset gather, mid-offset gather, and far-offset gather;

[0098] It should be noted that in some embodiments, step S400 may include: dividing the seismic data in the target gather with an offset-depth ratio less than or equal to the first offset-depth ratio threshold into a near-offset gather; dividing the seismic data in the target gather with an offset-depth ratio greater than the first offset-depth ratio threshold and less than or equal to the second offset-depth ratio threshold into a mid-offset gather; dividing the seismic data in the target gather with an offset-depth ratio greater than the second offset-depth ratio threshold into a far-offset gather.

[0099] Exemplarily, in some specific embodiments, for example, an offset-depth ratio less than 0.5 is defined as near-offset, an offset-depth ratio between 0.5 - 1.0 is defined as mid-offset, and an offset-depth ratio greater than 1.0 is defined as far-offset. (In fact, it may be more intuitive to define it in terms of the incident angle. For example, 0 - 15 degrees is near-offset, 15 - 30 degrees is mid-offset, and more than 30 degrees is far-offset. The incident angle and the offset-depth ratio can be converted through simple conversion. Here, the offset-depth ratio is used because it is more convenient to understand the subsequent expressions). Specifically, the gather can be split into Figure 5The three-segment trace gather shown, namely the near-offset trace gather ( Figure 5 left box), the mid-offset trace gather ( Figure 5 middle box), and the far-offset trace gather ( Figure 5 right box).

[0100] S500. Perform velocity analysis on each segment of the trace gather to obtain the velocity information corresponding to each seismic data in the trace gather segments;

[0101] Among them, the velocity analysis can adopt the conventional velocity analysis method for seismic wave data, which is not limited by the embodiments of the present invention and will not be elaborated here. Exemplarily, in some specific embodiments, velocity analysis can be performed separately on the segmented trace gathers, and 3 velocity models can be obtained, namely the near-offset velocity, the mid-offset velocity, and the far-offset velocity. The differences among these 3 velocity models characterize the anisotropy of the formation.

[0102] S600. Determine the depth-offset ratio increment corresponding to each seismic data in all trace gather segments based on a preset first depth-offset ratio threshold value;

[0103] It should be noted that in some embodiments, step S600 may include: determining the depth-offset ratio increment corresponding to each seismic data according to the difference between the depth-offset ratio corresponding to each seismic data in the mid-offset trace gather and the far-offset trace gather and the first depth-offset ratio threshold value; among them, the depth-offset ratio increment corresponding to each seismic data in the near-offset trace gather is determined to be 0.

[0104] Exemplarily, in some specific embodiments, the definition of the depth-offset ratio increment is as follows. For example, when the defined depth-offset ratio is 0.5 for the near offset, the depth-offset ratio increment at the depth-offset ratio of 0.8 is 0.3.

[0105] S700. Based on the depth-offset ratio increment and in combination with a preset P-wave anisotropy parameter, obtain the P-wave anisotropic velocity at the offset corresponding to the seismic data corresponding to the depth-offset ratio increment;

[0106] It should be noted that the P-wave anisotropic parameters include the medium-offset parameter and the far-offset parameter; in some embodiments, step S700 may include: presetting a correction velocity based on the velocity information of the trace gather segmentation; the correction velocity includes the near-offset velocity, the medium-offset velocity, and the far-offset velocity; wherein, the P-wave anisotropic parameters are set based on the correction velocity; when the seismic data corresponding to the offset-depth ratio increment belongs to the medium-offset trace gather, the near-offset velocity is adjusted by the first increment based on the product of the medium-offset parameter and the offset-depth ratio increment to obtain the P-wave anisotropic velocity at the offset corresponding to the seismic data; when the seismic data corresponding to the offset-depth ratio increment belongs to the far-offset trace gather, the near-offset velocity is adjusted by the second increment based on the product of the far-offset parameter and the offset-depth ratio increment to obtain the P-wave anisotropic velocity at the offset corresponding to the seismic data. In some embodiments, for example, the velocity corresponding to the offset-depth ratio at the maximum end point of the near-offset range (i.e., the first offset-depth ratio boundary value) (obtained from the velocity information analyzed in step S500) can be set as the near-offset velocity, and similarly, the medium-offset velocity and the far-offset velocity can be set.

[0107] Among them, in some embodiments, the method further includes: setting the P-wave anisotropic parameters based on the correction velocity in combination with the range interval values of the offset-depth ratios corresponding to the medium-offset trace gather and the far-offset trace gather; wherein, the expression of the medium-offset parameter is:

[0108]

[0109] In the formula, g p_mid represents the medium-offset parameter; v p_mid represents the medium-offset velocity; v p_near represents the near-offset velocity; rod mid represents the range interval value of the offset-depth ratio corresponding to the medium-offset trace gather;

[0110] The expression of the far-offset parameter is:

[0111]

[0112] In the formula, g p_far represents the far-offset parameter; v p_far represents the far-offset velocity; rod far represents the range interval value of the offset-depth ratio corresponding to the far-offset trace gather.

[0113] S800. Obtain the target travel time based on the P-wave anisotropic velocity, and perform NMO correction on the target transversely isotropic medium according to the target travel time.

[0114] It should be noted that in some embodiments, step S800 may include: obtaining the reflection time of the target reflection interface in the target transversely isotropic medium at zero offset; obtaining the equivalent depth of the target reflection interface based on the product of the longitudinal wave anisotropic velocity and half of the reflection time; obtaining the target travel time based on the equivalent depth, the longitudinal wave anisotropic velocity, and its corresponding offset through a preset NMO formula; wherein, the expression of the preset NMO formula is:

[0115]

[0116] In the formula, t(x) represents the target travel time; x s represents half of the offset corresponding to the longitudinal wave anisotropic velocity; z eff represents; represents the equivalent depth; v p(x) represents the longitudinal wave anisotropic velocity;

[0117] Perform normal moveout correction on the target transversely isotropic medium according to the difference between the target travel time and half of the reflection time.

[0118] Exemplarily, in some specific embodiments, the principle of normal moveout correction based on the depth-offset ratio increment according to steps S700 and S800 is as follows:

[0119] The NMO formula for PP waves in VTI media provided by the embodiments of the present invention is as follows:

[0120]

[0121] where x s is half of the offset, z eff represents the equivalent depth at this offset, v p(x) represents the longitudinal wave anisotropic velocity at this offset, and this velocity changes with time and offset. Its change with time characterizes the change in the seismic wave propagation velocity of the formation medium in the vertical direction, and its change with offset characterizes anisotropy.

[0122]

[0123] v p(x) = v p_near ·(1 + g p ·Δord) (3)

[0124] Among them, t0 refers to the reflection time of a certain reflection interface at zero offset. Since it is a two-way time, that is, the recorded time is the time when the seismic wave propagates to the interface and returns to the geophone, when calculating the equivalent depth, it needs to be divided by 2. Δord represents the increment of the offset-depth ratio. For example, when defining the offset-depth ratio of 0.5 as the near offset, the offset-depth ratio increment at the offset-depth ratio of 0.8 is 0.3, and the offset-depth ratio is the ratio of the offset to the calculated equivalent depth. Δord is the parameter for linear fitting of anisotropy; g p is the P-wave anisotropy parameter, which is divided into two parameters: the mid-offset parameter and the far-offset parameter, and are respectively expressed as follows:

[0125]

[0126] Among them, v p_near , v p_mid and v p_far are the near-offset, mid-offset and far-offset velocities obtained during velocity analysis respectively. rod mid and rod far represent the range of the offset-depth ratio for the mid-offset and far-offset respectively. For example, if the mid-offset depth ratio is 0.5 - 1.5, then the value of rod mid is 1.0.

[0127] In this regard, for the near-offset velocity, both its g p and Δord are 0; for the mid-offset velocity, its expression is v p(x) = v p_near ·(1 + g p_mid ·Δord); for the far-offset velocity, its expression is v p(x) = v p_near ·(1 + g p_far ·Δord).

[0128] To explain the principle of the technical solution of the present invention in detail, the overall process of the present invention will be described below in conjunction with some specific embodiments. It is easy to understand that the following is an explanation of the technical principle of the present invention and should not be regarded as a limitation of the present invention.

[0129] First of all, it should be noted that the present invention embodiment introduces the concept of non-hyperbolic propagation distance:

[0130] The seismic travel time t s at a certain offset of the t0 sampling point = l s / v α , where v α refers to the seismic wave anisotropic velocity, and the travel distance Where s is half of the offset, and v0 is the seismic wave propagation velocity at zero offset at the t0 sampling point. However, in actual situations, due to the presence of anisotropy, the travel distance is also non-hyperbolic. Therefore, anisotropy needs to be considered in the process of calculating the travel distance, that is The travel time obtained in this way can better fit the time-distance curve.

[0131] In view of this, as Figure 6 shown, the process principle of the PP-wave VTI medium NMO correction method based on segmented velocity modeling provided by the embodiments of the present invention is realized as follows:

[0132] The segmented velocity modeling in the embodiments of the present invention is divided according to the offset-depth ratio. Through conventional velocity analysis, a preliminary seismic wave propagation velocity model can be obtained. This velocity model is in the time domain, and then it can be converted from velocity and time to depth. By defining the ratio of the offset to the depth, the gather is cut. Therefore, the definition of the offset-depth ratio (ord) is the ratio of the offset to the depth (the calculation formula of the depth is the same as formula 2 below, but the velocity used is the velocity obtained from the original analysis, denoted as Vp0(x)). For example, the offset-depth ratio less than 0.5 is defined as near offset, the ratio between 0.5 - 1.0 is defined as medium offset, and the ratio greater than 1.0 is defined as far offset. (In fact, it may be more intuitive to define it in terms of the incident angle. For example, 0 - 15 degrees is near offset, 15 - 30 degrees is medium offset, and more than 30 degrees is far offset. The incident angle and the offset-depth ratio can be converted through simple conversion. Here, the offset-depth ratio is used because it is more convenient to understand the subsequent expressions). By performing velocity analysis on the segmented gathers respectively, 3 velocity models can be obtained, namely the near-offset velocity, the medium-offset velocity, and the far-offset velocity. The differences among these 3 velocity models characterize the anisotropy of the formation.

[0133] Among them, the concept of the velocity model is as follows:

[0134] By performing conventional velocity analysis on 1 CMP gather, a 1D velocity can be obtained, that is, the seismic wave propagation velocity at different times. 8000 CMPs form a 2D velocity profile. After introducing the concept of anisotropy, the original velocity model will rise from 2D to 3D, and the third dimension is the offset. Theoretically, the velocity model with the highest accuracy is that there is a corresponding 2D velocity profile for each offset. However, if all offsets are analyzed, the workload is too large and the efficiency is too low. Therefore, through offset-depth ratio sorting, 3 2D velocity profiles are obtained, and a 3D velocity model is fitted by interpolation.

[0135] Based on the aforementioned concept of non-hyperbolic travel distance, the PP-wave VTI medium NMO correction formula provided by the embodiments of the present invention is as follows:

[0136]

[0137] where x s is 1 / 2 of the offset, and z eff represents the equivalent depth at this offset, and v p(x) represents the P-wave anisotropic velocity at this offset, which varies with time and offset. Its variation with time characterizes the change in the seismic wave propagation velocity of the formation medium in the vertical direction, and its variation with offset characterizes anisotropy.

[0138]

[0139] v p(x) = v p_near ·(1 + g p ·Δord) (3)

[0140] where t0 is the reflection time of a certain reflection interface at zero offset. Since it is a two-way time, that is, the recorded time is the time when the seismic wave propagates to the interface and returns to the geophone, when calculating the equivalent depth, it needs to be divided by 2. Δord represents the increment of the depth-offset ratio. For example, when defining the depth-offset ratio of 0.5 as near offset, the increment of the depth-offset ratio at a depth-offset ratio of 0.8 is 0.3, and the depth-offset ratio is the ratio of the offset to the calculated equivalent depth. Δord is the parameter for linearly fitting anisotropy; g p is the P-wave anisotropic parameter, which is divided into two parts: the medium-offset parameter and the far-offset parameter, and are respectively expressed as follows:

[0141]

[0142] where v p_near , v p_mid and v p_far are the near-offset, medium-offset, and far-offset velocities obtained during velocity analysis respectively, rod mid and rod far represent the range of the depth-offset ratio for medium-offset and far-offset respectively. For example, if the medium-offset depth-offset ratio is 0.5 - 1.5, then the value of rod mid is 1.0.

[0143] In this regard, for the near-offset velocity, both its g p and Δord are 0; for the medium-offset velocity, its expression is v p(x) = v p_near ·(1 + g p_mid ·Δord); for the far-offset velocity, its expression is v p(x) = v p_near ·(1 + g p_far ·Δord).

[0144] Finally, traverse each sampling point and each seismic trace to obtain the corresponding t(x), and then perform NMO correction based on the difference between the obtained t(x) and the corresponding sampling point and seismic trace at the zero-offset travel time.

[0145] Exemplarily, in some specific embodiments, taking medium-offset velocity analysis as an example, as Figure 7 shown, through velocity analysis, obtain the velocity that can flatten the medium-offset gather.

[0146] Obtain the near-offset velocity and far-offset velocity in the same way, and then use the previous NMO correction formula to complete the NMO correction of the gather. The NMO correction effect obtained is as Figure 8 shown. The far-offset gather has been well flattened, achieving an ideal NMO correction effect.

[0147] The object of the present invention is to create an NMO correction formula that can better fit the seismic travel-time curve. The core of the NMO correction formula is the calculation of the travel time, and the calculation of the travel time is simply the distance divided by the velocity. In VTI media, the lateral propagation of seismic waves is unevenly distributed, which results in the non-hyperbolic nature of the travel-time curve. In the existing VTI anisotropic NMO correction formulas, the common problem is that when incorporating VTI anisotropic parameters into the travel-time calculation process, only the influence of anisotropic parameters on velocity is considered, while the influence on the travel distance is ignored. The present invention establishes a more accurate VTI media NMO correction formula by considering the non-hyperbolic nature of the travel distance and using the method of piecewise velocity analysis and modeling.

[0148] On the other hand, as Figure 9As shown in the figure, an embodiment of the present invention provides a PP-wave VTI medium dynamic correction device 900 based on segmented velocity modeling, which may include: a first module 910, configured to obtain seismic data of a target transversely isotropic medium to be dynamically corrected, and then organize and obtain a target gather; the seismic data is obtained based on PP waves; a second module 920, configured to perform velocity analysis on the target gather to obtain an initial velocity model in the time domain; convert the velocity and time information in the initial velocity model to obtain depth information corresponding to each seismic data in the target gather; a third module 930, configured to obtain the offset-depth ratio of each seismic data based on the ratio of the offset corresponding to the seismic data to the depth information; wherein, the offset represents the distance between the seismic source generating the seismic data and the geophone receiving the seismic data; a fourth module 940, configured to cut the target gather based on the offset-depth ratio to obtain a preset number of gather segments; the gather segments include a near-offset gather, a mid-offset gather, and a far-offset gather; a fifth module 950, configured to perform velocity analysis on the gather segments to obtain velocity information corresponding to each seismic data in the gather segments; a sixth module 960, configured to determine the offset-depth ratio increment corresponding to each seismic data in all gather segments based on a preset first offset-depth ratio boundary value; a seventh module 970, configured to obtain the P-wave anisotropic velocity at the offset corresponding to the seismic data corresponding to the offset-depth ratio increment by combining the offset-depth ratio increment with a preset P-wave anisotropic parameter; an eighth module 980, configured to obtain a target travel time based on the P-wave anisotropic velocity, and perform dynamic correction on the target transversely isotropic medium according to the target travel time.

[0149] It should be noted that in some embodiments, the device may further include: a ninth module, configured to set the P-wave anisotropic parameter based on the correction velocity and in combination with the range interval values of the offset-depth ratios corresponding to the mid-offset gather and the far-offset gather.

[0150] Among them, the expression of the mid-offset parameter is:

[0151]

[0152] In the formula, g p_mid represents the mid-offset parameter; v p_mid represents the mid-offset velocity; v p_near represents the near-offset velocity; rod mid represents the range interval value of the offset-depth ratio corresponding to the mid-offset gather.

[0153] The expression of the far-offset parameter is:

[0154]

[0155] In the formula, g p_far represents the far-offset parameter; v p_far represents the far-offset velocity; rod far represents the range interval value of the offset-depth ratio corresponding to the far-offset gather.

[0156] The content of the method embodiments of the present invention is applicable to the device embodiments of the present invention. The functions specifically implemented by the device embodiments are the same as those of the above method embodiments, and the beneficial effects achieved are also the same as those of the above method.

[0157] On the other hand, an embodiment of the present invention also provides an electronic device, which includes a memory and a processor. The memory stores a computer program, and when the processor executes the computer program, the above method for predicting the bottom boundary of the hydrate stability zone is implemented. The electronic device can be any intelligent terminal including a tablet computer, an in-vehicle computer, etc.

[0158] It can be understood that the content in the above method embodiments is applicable to the device embodiments of the present invention. The functions specifically implemented by the device embodiments are the same as those of the above method embodiments, and the beneficial effects achieved are also the same as those of the above method embodiments.

[0159] As Figure 10 shown, Figure 10 The hardware structure of an electronic device according to another embodiment is schematically shown. The electronic device includes:

[0160] A processor 1001, which can be implemented in a general-purpose CPU (Central Processing Unit), a microprocessor, an application-specific integrated circuit (ASIC), or one or more integrated circuits, etc., and is used to execute relevant programs to implement the technical solutions provided by the embodiments of the present invention;

[0161] A memory 1002, which can be implemented in the form of a read-only memory (ROM), a static storage device, a dynamic storage device, or a random access memory (RAM), etc. The memory 1002 can store an operating system and other application programs. When implementing the technical solutions provided in the embodiments of this specification through software or firmware, the relevant program codes are stored in the memory 1002 and are called by the processor 1001 to execute the method for optimizing the network node population in the embodiments of the present invention;

[0162] An input / output interface 1003, which is used to implement information input and output;

[0163] A communication interface 1004, which is used to implement communication interaction between the device and other devices, and can implement communication through a wired method (such as USB, network cable, etc.) or through a wireless method (such as a mobile network, WIFI, Bluetooth, etc.);

[0164] A bus 1005 transmits information between various components of the device (such as a processor 1001, a memory 1002, an input / output interface 1003, and a communication interface 1004);

[0165] Among them, the processor 1001, the memory 1002, the input / output interface 1003, and the communication interface 1004 achieve communication connections with each other inside the device through the bus 1005.

[0166] The electronic device embodiments described above are merely illustrative. The units described as separate components may or may not be physically separated, that is, they may be located in one place or distributed to multiple network units. Some or all of the modules can be selected according to actual needs to achieve the purpose of the solution of this embodiment.

[0167] The content of the method embodiments of the present invention is applicable to the electronic device embodiments of the present invention. The functions specifically implemented by the electronic device embodiments of the present invention are the same as those of the above method embodiments, and the beneficial effects achieved are also the same as those of the above method.

[0168] Another aspect of the embodiments of the present invention also provides a computer-readable storage medium. The storage medium stores a program, and the program is executed by a processor to implement the foregoing method.

[0169] It should be noted that the computer-readable medium shown in the embodiments of the present invention can be a computer-readable signal medium, a computer-readable storage medium, or any combination of the above two. The computer-readable storage medium can be, for example, but not limited to, an electrical, magnetic, optical, electromagnetic, infrared, or semiconductor system, apparatus, or device, or any combination of the above. More specific examples of the computer-readable storage medium can include, but are not limited to: an electrical connection with one or more wires, a portable computer disk, a hard disk, a random access memory (RAM), a read-only memory (ROM), an erasable programmable read-only memory (EPROM), a flash memory, an optical fiber, a portable compact disc read-only memory (CD-ROM), an optical storage device, a magnetic storage device, or any suitable combination of the above. In the present invention, the computer-readable storage medium can be any tangible medium that contains or stores a program, and this program can be used by or in combination with an instruction execution system, apparatus, or device. In the present invention, the computer-readable signal medium can include a data signal propagated in a baseband or as part of a carrier wave, which carries computer-readable program code. Such a propagated data signal can take various forms, including but not limited to electromagnetic signals, optical signals, or any suitable combination of the above. The computer-readable signal medium can also be any computer-readable medium other than the computer-readable storage medium, and this computer-readable medium can send, propagate, or transmit a program for use by or in combination with an instruction execution system, apparatus, or device. The program code contained on the computer-readable medium can be transmitted by any suitable medium, including but not limited to: wireless, wired, etc., or any suitable combination of the above.

[0170] The content of the method embodiments of the present invention is applicable to the embodiments of this computer-readable storage medium. The functions specifically implemented by the embodiments of this computer-readable storage medium are the same as those of the above method embodiments, and the beneficial effects achieved are also the same as those of the above method.

[0171] The embodiments of the present invention also disclose a computer program product or a computer program. The computer program product or the computer program includes computer instructions, and the computer instructions are stored in a computer-readable storage medium. The processor of the computer device can read the computer instructions from the computer-readable storage medium, and the processor executes the computer instructions, so that the computer device executes the foregoing method.

[0172] The flowcharts and block diagrams in the accompanying drawings illustrate the possible architectures, functions, and operations of systems, methods, and computer program products according to various embodiments of the present invention. In this regard, each block in the flowchart or block diagram may represent a module, a segment of a program, or a part of code, and the above-mentioned module, segment of a program, or part of code contains one or more executable instructions for implementing the specified logical function. It should also be noted that in some alternative implementations, the functions marked in the blocks may occur in a different order than that marked in the accompanying drawings. For example, two consecutive blocks shown may actually be executed substantially in parallel, and they may sometimes be executed in the reverse order, depending on the functions involved. It should also be noted that each block in the block diagram or flowchart, as well as combinations of blocks in the block diagram or flowchart, can be implemented by a dedicated hardware-based system that performs the specified functions or operations, or can be implemented by a combination of dedicated hardware and computer instructions.

[0173] It should be noted that although several modules of devices for action execution are mentioned in the above detailed description, this division is not mandatory. In fact, according to the embodiments of the present invention, the features and functions of the two or more modules or units described above can be embodied in one module or unit. Conversely, the features and functions of one module or unit described above can be further divided and embodied by multiple modules or units.

[0174] Through the description of the above embodiments, those skilled in the art can easily understand that the example embodiments described herein can be implemented by software or by a combination of software and necessary hardware. Therefore, the technical solutions according to the embodiments of the present invention can be embodied in the form of a software product, which can be stored in a non-volatile storage medium (which can be a CD-ROM, a USB flash drive, a mobile hard disk, etc.) or on a network, including several instructions to enable a computing device (which can be a personal computer, a server, a touch terminal, or a network device, etc.) to execute the method according to the embodiments of the present invention.

[0175] In some alternative embodiments, the functions / operations mentioned in the block diagram may not occur in the order mentioned in the operation diagram. For example, depending on the functions / operations involved, two consecutive blocks shown may actually be executed substantially simultaneously or the blocks can sometimes be executed in the reverse order. In addition, the embodiments presented and described in the flowcharts of the present invention are provided by way of example for the purpose of providing a more comprehensive understanding of the technology. The disclosed methods are not limited to the operations and logical flows presented herein. Alternative embodiments are contemplated, in which the order of various operations is changed and the sub-operations described as part of a larger operation are executed independently.

[0176] In addition, although the present invention has been described in the context of functional modules, it should be understood that, unless otherwise stated to the contrary, one or more of the functions and / or features may be integrated in a single physical device and / or software module, or one or more functions and / or features may be implemented in separate physical devices or software modules. It should also be understood that a detailed discussion of the actual implementation of each module is not necessary for understanding the present invention. Rather, considering the attributes, functions, and internal relationships of the various functional modules in the devices disclosed herein, the actual implementation of the modules will be understood within the ordinary skills of an engineer. Therefore, those skilled in the art can implement the present invention as set forth in the claims without undue experimentation. It should also be understood that the specific concepts disclosed are merely illustrative and are not intended to limit the scope of the present invention, which is determined by the full scope of the appended claims and their equivalents.

[0177] If a function is implemented in the form of a software functional unit and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the present invention, in essence, or the part that contributes to the prior art, or a part of this technical solution, can be embodied in the form of a software product. This computer software product is stored in a storage medium and includes several instructions for causing a computer device (which may be a personal computer, a server, or a network device, etc.) to execute all or part of the steps of the methods of the various embodiments of the present invention. The aforementioned storage medium includes: various media such as USB flash drives, mobile hard disks, read-only memories (ROM, Read-Only Memory), random access memories (RAM, Random Access Memory), magnetic disks, or optical discs that can store program codes.

[0178] The logic and / or steps represented in the flowchart or otherwise described herein, for example, can be considered as a definite sequence list of executable instructions for implementing logical functions, and can be specifically implemented in any computer-readable medium for use by an instruction execution device, apparatus, or equipment (such as a computer-based device, a device including a processor, or other devices that can fetch instructions from the instruction execution device, apparatus, or equipment and execute the instructions), or in combination with these instruction execution devices, apparatuses, or equipment. For the purposes of this specification, a "computer-readable medium" can be any device that can contain, store, communicate, propagate, or transmit a program for use by or in combination with an instruction execution device, apparatus, or equipment.

[0179] More specific examples (a non-exhaustive list) of computer-readable media include the following: an electrical connection (electronic device) having one or more wirings, a portable computer diskette (magnetic device), a random access memory (RAM), a read-only memory (ROM), an erasable programmable read-only memory (EPROM or flash memory), an optical fiber device, and a portable compact disc read-only memory (CDROM). Additionally, the computer-readable media can even be paper or other suitable media on which a program can be printed, as the program can be obtained electronically, for example, by optically scanning the paper or other media, followed by editing, interpretation, or, if necessary, other suitable processing, and then stored in a computer memory.

[0180] It should be understood that the various parts of the present invention can be implemented by hardware, software, firmware, or a combination thereof. In the above-described embodiments, multiple steps or methods can be implemented by software or firmware stored in a memory and executed by a suitable instruction execution device. For example, if implemented by hardware, as in another embodiment, any one or a combination of the following techniques well-known in the art can be used: discrete logic circuits having logic gate circuits for implementing logical functions on data signals, application-specific integrated circuits having appropriate combinational logic gate circuits, programmable gate arrays (PGAs), field-programmable gate arrays (FPGAs), and the like.

[0181] In the description of this specification, the description with reference to terms such as "one embodiment", "some embodiments", "example", "specific example", or "some examples", etc. means that the specific features, structures, materials, or characteristics described in connection with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials, or characteristics described can be combined in any one or more embodiments or examples in a suitable manner.

[0182] Although the embodiments of the present invention have been shown and described, those of ordinary skill in the art can understand that various changes, modifications, substitutions, and variations can be made to these embodiments without departing from the principles and spirit of the present invention, and the scope of the present invention is defined by the claims and their equivalents.

[0183] The above has specifically described the preferred embodiments of the present invention, but the present invention is not limited to the embodiments. Those skilled in the art can also make various equivalent deformations or substitutions without departing from the spirit of the present invention, and these equivalent deformations or substitutions are all included in the scope defined by the claims of the present invention.

Claims

1. A dynamic correction method for PP waves in VTI media based on piecewise velocity modeling, characterized in that Including: Obtaining seismic data of a target transversely isotropic medium to be NMO corrected, and then sorting to obtain a target gather; The seismic data is obtained based on PP waves; Performing velocity analysis on the target gather to obtain an initial velocity model in the time domain; converting to obtain depth information corresponding to each piece of the seismic data in the target gather based on the velocity and time information in the initial velocity model; Obtaining a depth-offset ratio for each piece of the seismic data based on the ratio of the offset corresponding to the seismic data to the depth information; wherein, the offset represents the distance between the seismic source generating the seismic data and the geophone receiving the seismic data; Cutting the target gather based on the depth-offset ratio to obtain a preset number of gather segments; the gather segments include a near-offset gather, a mid-offset gather, and a far-offset gather; Performing velocity analysis on the gather segments to obtain velocity information corresponding to each piece of seismic data in the gather segments; Determining a depth-offset ratio increment corresponding to each piece of the seismic data in all the gather segments based on a preset first depth-offset ratio threshold; Obtaining a P-wave anisotropic velocity at the offset corresponding to the seismic data corresponding to the depth-offset ratio increment based on the depth-offset ratio increment in combination with a preset P-wave anisotropic parameter; Obtaining a target travel time based on the P-wave anisotropic velocity, and performing NMO correction on the target transversely isotropic medium according to the target travel time.

2. The PP wave VTI medium dynamic correction method based on segmented velocity modeling according to claim 1, characterized in that, The obtaining of seismic data of a target transversely isotropic medium to be NMO corrected, and then sorting to obtain a target gather, includes: Obtaining seismic traces of each geophone arranged in the target transversely isotropic medium to be NMO corrected; Arranging all the seismic traces in ascending order of offset to obtain a common midpoint gather.

3. The dynamic correction method for PP wave VTI medium based on segmented velocity modeling according to claim 1, characterized in that, The cutting of the target gather based on the depth-offset ratio to obtain a preset number of gather segments includes: Dividing the seismic data in the target gather with a depth-offset ratio less than or equal to the first depth-offset ratio threshold into the near-offset gather; Dividing the seismic data in the target gather with a depth-offset ratio greater than the first depth-offset ratio threshold and less than or equal to a second depth-offset ratio threshold into the mid-offset gather; Dividing the seismic data in the target gather with a depth-offset ratio greater than the second depth-offset ratio threshold into the far-offset gather.

4. The PP wave VTI medium dynamic correction method based on piecewise velocity modeling according to claim 1, characterized in that The determining of a depth-offset ratio increment corresponding to each piece of the seismic data in all the gather segments based on a preset first depth-offset ratio threshold includes: Determining the depth-offset ratio increment corresponding to each piece of the seismic data according to the difference between the depth-offset ratio corresponding to each piece of the seismic data in the mid-offset gather and the far-offset gather and the first depth-offset ratio threshold; Wherein, the depth-offset ratio increment corresponding to each piece of the seismic data in the near-offset gather is determined to be 0.

5. The PP-wave VTI medium dynamic correction method based on segmented velocity modeling according to claim 1, wherein The P-wave anisotropic parameter includes a mid-offset parameter and a far-offset parameter; the obtaining of a P-wave anisotropic velocity at the offset corresponding to the seismic data corresponding to the depth-offset ratio increment based on the depth-offset ratio increment in combination with a preset P-wave anisotropic parameter includes: Preset a correction velocity based on the velocity information of the seismic gather segmentation; the correction velocity includes a near-offset velocity, a mid-offset velocity, and a far-offset velocity; wherein, the P-wave anisotropy parameter is set based on the correction velocity; When the seismic data corresponding to the offset-depth ratio increment belongs to the mid-offset gather, perform a first increment adjustment on the near-offset velocity based on the product of the mid-offset parameter and the offset-depth ratio increment to obtain the P-wave anisotropy velocity at the offset corresponding to the seismic data; When the seismic data corresponding to the offset-depth ratio increment belongs to the far-offset gather, perform a second increment adjustment on the near-offset velocity based on the product of the far-offset parameter and the offset-depth ratio increment to obtain the P-wave anisotropy velocity at the offset corresponding to the seismic data.

6. The PP wave VTI medium dynamic correction method based on segmented velocity modeling according to claim 5, characterized in that The method further includes: Based on the correction velocity, set the P-wave anisotropy parameter by combining the range interval values of the offset-depth ratios corresponding to the mid-offset gather and the far-offset gather; Wherein, the expression of the mid-offset parameter is: where g p_mid represents the medium deviation parameter; v p_mid represents the medium deviation velocity; v p_near represents the near deviation velocity; rod mid represents the range interval value of the deviation depth ratio corresponding to the medium deviation gather; The expression of the far-offset parameter is: In the formula, g p_far represents the far-offset parameter; v p_far represents the far-offset velocity; rod far represents the range interval value of the offset-depth ratio corresponding to the far-offset gather.

7. The PP-wave VTI medium NMO correction method based on piecewise velocity modeling according to claim 1, characterized in that When obtaining the target travel time based on the P-wave anisotropy velocity and performing NMO correction on the target transversely isotropic medium according to the target travel time, it includes: Obtain the reflection time of the target reflection interface in the target transversely isotropic medium at zero offset; Based on the product of the P-wave anisotropy velocity and half of the reflection time, obtain the equivalent depth of the target reflection interface; Based on the equivalent depth, the P-wave anisotropy velocity, and its corresponding offset, obtain the target travel time through a preset NMO correction formula; Wherein, the expression of the preset NMO correction formula is: Where \(t(x)\) represents the target travel time; \(x\) s represents half of the offset corresponding to the P-wave anisotropic velocity; \(z\) eff represents the equivalent depth; \(v\) p(x) represents the P-wave anisotropic velocity; Perform NMO correction on the target transversely isotropic medium according to the difference between the target travel time and half of the reflection time.

8. A PP-wave VTI medium dynamic correction device based on piecewise velocity modeling, characterized in that, It includes: A first module, configured to obtain the seismic data of the target transversely isotropic medium to be NMO corrected, and then organize it to obtain a target gather; The seismic data is obtained based on PP waves; A second module, configured to perform velocity analysis on the target gather to obtain an initial velocity model in the time domain; convert the velocity and time information in the initial velocity model to obtain the depth information corresponding to each piece of seismic data in the target gather; A third module, configured to obtain the offset-depth ratio of each piece of seismic data based on the ratio of the offset corresponding to the seismic data to the depth information; wherein, the offset represents the distance between the seismic source generating the seismic data and the geophone receiving the seismic data; A fourth module, configured to perform cutting on the target gather based on the offset-depth ratio to obtain a preset number of gather segments; the gather segments include a near-offset gather, a mid-offset gather, and a far-offset gather; A fifth module, configured to perform velocity analysis on the gather segments to obtain the velocity information corresponding to each piece of seismic data in the gather segments; A sixth module, configured to determine the offset-depth ratio increment corresponding to each piece of seismic data in all the gather segments based on a preset first offset-depth ratio threshold value; The seventh module is configured to obtain the P-wave anisotropic velocity at the offset corresponding to the seismic data corresponding to the depth ratio increment based on the depth ratio increment in combination with preset P-wave anisotropic parameters; The eighth module is configured to obtain a target travel time based on the P-wave anisotropic velocity, and perform dynamic correction on the target transversely isotropic medium according to the target travel time.

9. An electronic device, characterized in that, It includes a processor and a memory; The memory is used to store programs; The processor executes the program to implement the method according to any one of claims 1 to 7.

10. A computer storage medium storing a program executable by a processor, characterized in that, The program executable by the processor, when executed by the processor, is used to implement the method according to any one of claims 1 to 7.

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