Method and apparatus for dividing incident angle gathers

Abstract

The embodiments of this specification provide a method and device for dividing incident angle gather. The method for dividing incident angle gather includes: obtaining the incident angle gather of the completed well in the target time window for the target horizon; determining the amplitude characteristic distribution and waveform coefficient characteristic distribution of the incident angle gather in the target time window; dividing the incident angle gather in the amplitude characteristic dimension according to the amplitude characteristic distribution, generating the first gather division information according to the amplitude division result, and dividing the incident angle gather in the waveform dimension according to the waveform coefficient characteristic distribution, generating the second gather division information according to the waveform division result; generating the target division information of the incident angle gather based on the first gather division information and the second gather division information. Generating the target division information of the incident angle gather based on the first gather division information and the second gather division information realizes the accurate and quantitative division of the incident angles of the incident angle gather, so as to facilitate the subsequent accurate implementation of prestack inversion work.

Description

Technical Field

[0001] The embodiments of this specification relate to the technical field of oil exploration and development, and particularly to a method and device for dividing incident angle gathers. Background Art

[0002] With the continuous deepening of oil and gas exploration and development work, the research objects have gradually shifted to lithologic-stratigraphic oil and gas reservoirs and unconventional oil and gas. The research focuses are mainly on favorable reservoir prediction and sweet spot prediction. The prestack seismic inversion technology is the core technology to solve the above problems. Prestack seismic inversion mainly includes prestack direct inversion, prestack simultaneous inversion, AVO inversion, and elastic impedance inversion, etc. Currently, most prestack seismic inversion technologies are carried out based on angle-separated stacked seismic data, that is, seismic traces within a certain incident angle range are stacked to form multiple angle-separated stacked seismic data volumes, and then prestack inversion work is carried out. If the incident angle division is unreasonable, accurate inversion results cannot be obtained.

[0003] In the prior art, the division method of the stacking angle of incident angle gathers is mainly equal incident angle division. First, the minimum incident angle and the maximum incident angle are analyzed, and then equal-spacing division is carried out. However, this incident angle division method only considers the uniformity of the incident angle distribution, and does not consider the AVO characteristics of the incident angle gathers and the amplitude differences of seismic traces within the incident angle range due to the AVO phenomenon during azimuth-separated stacking. Therefore, this method has certain limitations and cannot give a reasonable and accurate incident angle division. Therefore, there is an urgent need for a more reasonable method for dividing incident angle gathers to solve the above problems. Summary of the Invention

[0004] In view of this, the embodiments of this specification provide a method for dividing incident angle gathers. One or more embodiments of this specification simultaneously relate to a device for dividing incident angle gathers, a computing device, a computer-readable storage medium, and a computer program product to solve the technical defects existing in the prior art.

[0005] According to the first aspect of the embodiments of this specification, a method for dividing incident angle gathers is provided, including:

[0006] Obtaining the incident angle gathers of completed wells for the target horizon within the target time window;

[0007] Determining the amplitude characteristic distribution and waveform coefficient characteristic distribution of the incident angle gathers within the target time window;

[0008] Dividing the incident angle gathers in the amplitude characteristic dimension according to the amplitude characteristic distribution, generating the first gather division information according to the amplitude division result, and dividing the incident angle gathers in the waveform dimension according to the waveform coefficient characteristic distribution, generating the second gather division information according to the waveform division result;

[0009] Generate target partitioning information for the angle-of-incidence gather based on the first gather partitioning information and the second gather partitioning information, where the target partitioning information is used for pre-stack inversion.

[0010] Optionally, determining the amplitude characteristic distribution of the angle-of-incidence gather within the target time window includes:

[0011] Within the target time window, determine the correspondence between the angles of incidence included in the angle-of-incidence gather and the amplitude data of the target horizon;

[0012] Generate an amplitude characteristic map based on the correspondence and determine the amplitude characteristic distribution in the amplitude characteristic map.

[0013] Optionally, determining the waveform coefficient characteristic distribution of the angle-of-incidence gather within the target time window includes:

[0014] Determine at least two sets of adjacent traces in the angle-of-incidence gather associated with the target time window;

[0015] Generate a waveform coefficient characteristic distribution map based on the waveform correlation coefficients corresponding to the at least two sets of adjacent traces, and determine the waveform coefficient characteristic distribution in the waveform coefficient characteristic distribution map.

[0016] Optionally, partitioning the angle-of-incidence gather in the amplitude characteristic dimension according to the amplitude characteristic distribution includes:

[0017] Determine amplitude mutation points in the amplitude characteristic distribution, and determine first angle-of-incidence information corresponding to the amplitude mutation points based on the amplitude characteristic distribution;

[0018] Partition the angle-of-incidence gather based on the first angle-of-incidence information.

[0019] Optionally, partitioning the angle-of-incidence gather in the waveform dimension according to the waveform coefficient characteristic distribution includes:

[0020] Determine waveform mutation points in the waveform coefficient characteristic distribution, and determine second angle-of-incidence information corresponding to the waveform mutation points based on the waveform coefficient characteristic distribution;

[0021] Partition the angle-of-incidence gather based on the second angle-of-incidence information.

[0022] Optionally, generating the target partitioning information for the angle-of-incidence gather based on the first gather partitioning information and the second gather partitioning information includes:

[0023] Determine the first near-offset incident angle information, the first mid-offset incident angle information, and the first far-offset incident angle information corresponding to the incident angle gather based on the first gather division information, and determine the second near-offset incident angle information, the second mid-offset incident angle information, and the second far-offset incident angle information corresponding to the incident angle gather based on the second gather division information;

[0024] Determine the target near-offset incident angle information corresponding to the first near-offset incident angle information and the second near-offset incident angle information, the target mid-offset incident angle information corresponding to the first mid-offset incident angle information and the second mid-offset incident angle information, and the target far-offset incident angle information corresponding to the first far-offset incident angle information and the second far-offset incident angle information;

[0025] The target division information is composed of the target near-offset incident angle information, the target mid-offset incident angle information, and the target far-offset incident angle information.

[0026] Optionally, when there are multiple completed wells, obtaining the incident angle gather of the completed wells within the target time window for the target horizon includes:

[0027] Determine multiple completed wells, and obtain the initial incident angle gather of each completed well within the target time window for the target horizon;

[0028] The initial incident angle gather of each completed well is used as the incident angle gather.

[0029] Optionally, generating the target division information of the incident angle gather based on the first gather division information and the second gather division information includes:

[0030] Generate the initial division information of the incident angle gather based on the first gather division information and the second gather division information;

[0031] Determine the target traces in the incident angle gather based on the initial division information, and update the initial division information to the intermediate division information by removing the target traces;

[0032] Determine the corrected incident angle step size, and determine the central trace in the incident angle gather based on the intermediate division information;

[0033] Determine at least two calculation traces in the incident angle gather based on the incident angle step size, and calculate the correction values corresponding to the central trace and the at least two calculation traces respectively;

[0034] Determine at least two corrected amplitude values based on the at least two correction values and the at least two amplitude values corresponding to the incident angle gather;

[0035] Updating the initial amplitude values included in the intermediate partitioning information based on the at least two correction amplitude values to obtain the target partitioning information.

[0036] According to a second aspect of the embodiments of the present specification, there is provided an incident angle gather partitioning device, including:

[0037] An acquisition module configured to acquire the incident angle gather of the completed well drilling within a target time window for a target horizon;

[0038] A determination module configured to determine the amplitude characteristic distribution and the waveform coefficient characteristic distribution of the incident angle gather within the target time window;

[0039] A partitioning module configured to partition the incident angle gather in the amplitude characteristic dimension according to the amplitude characteristic distribution, generate first gather partitioning information according to the amplitude partitioning result, and partition the incident angle gather in the waveform dimension according to the waveform coefficient characteristic distribution, and generate second gather partitioning information according to the waveform partitioning result;

[0040] A generation module configured to generate target partitioning information of the incident angle gather based on the first gather partitioning information and the second gather partitioning information, where the target partitioning information is used for prestack inversion.

[0041] According to a third aspect of the embodiments of the present specification, there is provided a computing device, including:

[0042] A memory and a processor;

[0043] The memory is used to store computer-executable instructions, and the processor is used to execute the computer-executable instructions, and when the computer-executable instructions are executed by the processor, the steps of the above-mentioned incident angle gather partitioning method are implemented.

[0044] According to a fourth aspect of the embodiments of the present specification, there is provided a computer-readable storage medium storing computer-executable instructions, and when the instructions are executed by a processor, the steps of the above-mentioned incident angle gather partitioning method are implemented.

[0045] According to a fifth aspect of the embodiments of the present specification, there is provided a computer program product including a computer program or instructions, and when the computer program or instructions are executed by a processor, the steps of the above-mentioned incident angle gather partitioning method are implemented.

[0046] In one embodiment of this specification, for a target horizon, an incident angle gather of completed wells is obtained within a target time window. The amplitude characteristic distribution and waveform coefficient characteristic distribution of the incident angle gather within the target time window are determined. The incident angle gather is divided in the amplitude characteristic dimension according to the amplitude characteristic distribution, and first gather division information is generated based on the amplitude division result. Also, the incident angle gather is divided in the waveform dimension according to the waveform coefficient characteristic distribution, and second gather division information is generated based on the waveform division result. The target division information of the incident angle gather is generated based on the first gather division information and the second gather division information, realizing an accurate and quantitative division of the incident angles of the incident angle gather, so as to facilitate the subsequent accurate implementation of prestack inversion work. This provides a basis for the exploration and development of lithologic-stratigraphic oil and gas reservoirs and unconventional oil and gas. Description of the Drawings

[0047] Figure 1 is a schematic diagram of a method for dividing an incident angle gather provided by an embodiment of this specification;

[0048] Figure 2 is a flowchart of a method for dividing an incident angle gather provided by an embodiment of this specification;

[0049] Figure 3 is a schematic diagram of an incident angle gather of a method for dividing an incident angle gather provided by an embodiment of this specification;

[0050] Figure 4 is a schematic diagram of the amplitude characteristic distribution of a method for dividing an incident angle gather provided by an embodiment of this specification;

[0051] Figure 5 is a schematic diagram of the waveform coefficient characteristic distribution of a method for dividing an incident angle gather provided by an embodiment of this specification;

[0052] Figure 6 is a schematic diagram of special trace rejection of a method for dividing an incident angle gather provided by an embodiment of this specification;

[0053] Figure 7 is a flowchart of the processing procedure of a method for dividing an incident angle gather provided by an embodiment of this specification;

[0054] Figure 8 is a schematic diagram of the structure of a device for dividing an incident angle gather provided by an embodiment of this specification;

[0055] Figure 9 is a block diagram of the structure of a computing device provided by an embodiment of this specification. Detailed Embodiments

[0056] In the following description, numerous specific details are set forth in order to provide a thorough understanding of this specification. However, this specification can be implemented in many other ways different from those described herein, and those skilled in the art can make similar generalizations without departing from the connotation of this specification. Therefore, this specification is not limited by the specific implementations disclosed below.

[0057] The terms used in one or more embodiments of this specification are for the purpose of describing specific embodiments only and are not intended to limit one or more embodiments of this specification. The singular forms "a", "the", and "said" used in one or more embodiments of this specification and the appended claims are also intended to include the plural forms unless the context clearly dictates otherwise. It should also be understood that the term "and / or" used in one or more embodiments of this specification refers to and encompasses any and all possible combinations of one or more of the associated listed items.

[0058] It should be understood that although the terms first, second, etc. may be used in one or more embodiments of this specification to describe various information, such information should not be limited to these terms. These terms are only used to distinguish information of the same type from each other. For example, without departing from the scope of one or more embodiments of this specification, the first may also be referred to as the second, and similarly, the second may also be referred to as the first. Depending on the context, the word "if" as used herein may be interpreted as "when" or "while" or "in response to determining".

[0059] In addition, it should be noted that the user information (including but not limited to user device information, user personal information, etc.) and data (including but not limited to data for analysis, stored data, displayed data, etc.) involved in one or more embodiments of this specification are all information and data that have been authorized by the user or fully authorized by all parties, and the collection, use, and processing of the relevant data need to comply with the relevant laws, regulations, and standards of the relevant countries and regions, and corresponding operation entrances are provided for the user to choose to authorize or refuse.

[0060] First, the noun terms involved in one or more embodiments of this specification are explained.

[0061] Pre-stack inversion: Pre-stack seismic inversion, which uses pre-stack CRP gather data or partial stacked data, velocity data, and well data (such as shear wave velocity, compressional wave velocity, density, etc.), and through the use of different approximations to inversely solve for various elastic parameters related to lithology and hydrocarbon-bearing properties, and further uses them to predict reservoir lithology, reservoir physical properties, and hydrocarbon-bearing properties.

[0062] Post-stack seismic data: The original seismic data collected in the field, which after indoor data processing, finally forms the resulting data for geological interpretation after stacking.

[0063] Well logging: Also known as geophysical well logging, it refers to a method of measuring geophysical parameters by using the electrochemical properties, conductivity, acoustic properties, radioactivity, and other geophysical properties of rock formations, and it belongs to one of the applied geophysical methods.

[0064] Incident angle gather: The original seismic data collected in the field, after indoor static correction, noise removal, deconvolution and other processing, is subjected to migration imaging. After converting the migrated gather, the incident angle gather is obtained. This gather has not been stacked and retains the incident angle information.

[0065] Acoustic travel time logging: A well logging method that studies the characteristics of the drilling formation by using the different acoustic properties such as the velocity, amplitude, and frequency changes of sound waves when propagating in different rocks.

[0066] Density logging: A well logging method that irradiates the formation with gamma rays emitted by a gamma source and measures the bulk density of the formation according to the Compton effect.

[0067] Synthetic seismogram: A seismic record formed by artificial synthesis and conversion using acoustic travel time logging or vertical seismic profile data.

[0068] Reflection event: The connection of the extreme values with the same vibration phase on each trace of the seismic record.

[0069] Completed well: A hole drilled from the ground to underground using mechanical equipment.

[0070] AVO (Amplitude Variation with Offset): The variation of amplitude with offset. The AVO technique explores the variation of the reflection coefficient response with the offset (or incident angle) by studying the variation characteristics of the seismic reflection amplitude with the distance between the shot point and the receiver (i.e., the offset or incident angle).

[0071] Amplitude: The maximum displacement of a particle from its equilibrium position.

[0072] Incident angle: When analyzing the propagation of seismic waves based on ray theory, the angle between the incident wave and the normal of the incident surface.

[0073] Seismic wavelet: A short pulse vibration excited by a seismic source, propagated underground and received, is called the seismic wavelet of this vibration.

[0074] Forward modeling: In the case of known parameters and structures of underground media, the process of simulating the real seismic wave propagation process using physical equations and numerical calculation methods and obtaining a synthetic seismogram.

[0075] Zero-offset: A seismic signal acquisition method in which the excitation point and the receiving point of the seismic wave are located at the same position.

[0076] Figure 1It is a schematic diagram of a method for dividing an incident angle gather provided by an embodiment of this specification. In oil and gas exploration and development work, the use of prestack inversion technology can provide a basis for the exploration and development of lithologic-stratigraphic oil and gas reservoirs and unconventional oil and gas. The accurate implementation of prestack inversion depends on the division of the incident angles in the incident angle gather. Accurately and quantitatively dividing the incident angles of the incident angle gather can accurately carry out the prestack inversion work. As Figure 1 shown, obtain the incident angle gather of the completed well for the target horizon within the target time window. Among them, there is at least one completed well. In the case where there are two or more completed wells, it is necessary to obtain the incident angle gather for each completed well respectively, and divide the incident angles of each obtained incident angle gather.

[0077] After determining the incident angle gather, determine the amplitude characteristic distribution and waveform coefficient characteristic distribution of the incident angle gather within the target time window. Divide the incident angle gather in the amplitude characteristic dimension according to the amplitude characteristic distribution, generate the first gather division information based on the amplitude division result, and divide the incident angle gather in the waveform dimension according to the waveform coefficient characteristic distribution, generate the second gather division information based on the waveform division result. Generate the target division information of the incident angle gather based on the first gather division information and the second gather division information, realizing the accurate and quantitative division of the incident angles of the incident angle gather, so as to accurately carry out the prestack inversion work subsequently. Provide a basis for the exploration and development of lithologic-stratigraphic oil and gas reservoirs and unconventional oil and gas.

[0078] Analyze the amplitude values and waveform similarity characteristics between different seismic traces on the incident angle gather, and determine the optimal incident angle division scheme according to the amplitude values, correlation coefficient distribution, etc., and further obtain the best split-angle stacking data volume, which has important practical significance for improving the reliability of the prestack inversion result and the success rate of oil and gas field exploration and development.

[0079] In this specification, a method for dividing an incident angle gather is provided. This specification also relates to an incident angle gather division device, a computing device, a computer-readable storage medium, and a computer program product, which will be described in detail one by one in the following embodiments.

[0080] See Figure 2 , Figure 2 shows a flowchart of a method for dividing an incident angle gather provided by an embodiment of this specification, which specifically includes the following steps.

[0081] Step 202: Obtain the incident angle gather of the completed well for the target horizon within the target time window.

[0082] Specifically, a stratigraphic horizon refers to a geological stratigraphic horizon, which includes but is not limited to seismic horizons, lithologic horizons, fossil horizons, etc. The target horizon can be any geological stratigraphic horizon that can achieve lithology, physical property, and hydrocarbon-bearing property analysis. The target time window can be regarded as a time range, and the time measurement unit in the target time window can be seconds, milliseconds, etc.; a completed well is a hole drilled from the ground to the underground using mechanical equipment. An incident angle gather refers to the original seismic data collected in the field. After indoor static correction, denoising, deconvolution, and other processing, migration imaging is performed, and after converting the migrated gather, an incident angle gather is obtained. This gather is not stacked and is a gather that retains incident angle information.

[0083] Based on this, the target horizon for prestack seismic inversion is determined, and then the target time window is determined according to the target horizon. The selection of the target time window needs to completely contain the target horizon and be greater than half of a period. The incident angle gather of the completed well is obtained for the target horizon within the target time window.

[0084] Figure 3 It is a schematic diagram of an incident angle gather of a method for dividing an incident angle gather provided in an embodiment of this specification. Figure 3 It shows the relationship between the time in the target time window and the incident angle in the incident angle gather. Based on the schematic diagram of the incident angle gather, the incident angle gather of the target horizon within the target time window can be determined.

[0085] In practical applications, prestack seismic inversion is mainly carried out for a specific target horizon, so gather stacking is also analyzed for a specific target horizon. To determine the target horizon, post-stack seismic data and logging data are mainly used. Synthetic seismic records are made using the post-stack seismic data, acoustic travel time logging data, and density logging data in the study area, and horizon calibration is performed to determine the reflection isochron corresponding to the target horizon. Specifically, when implementing, synthetic seismic records of all wells are made using the post-stack seismic data corresponding to the incident angle gather, the acoustic travel time logging data, and the density logging data of all completed wells. The similarity between the synthetic seismic record and the post-stack seismic data at the well point is compared for each well. When the similarity between the two reaches the maximum, their corresponding relationship is determined. Thus, the geological stratification information on the well can be given to the post-stack seismic data, and further, the time window where the reflection isochron corresponding to the target horizon is located can be determined.

[0086] Furthermore, considering dividing the incident angle of the incident angle gather, in fact, it is to divide the incident angle of the incident angle gather at the completed well. Dividing the incident angle of the incident angle gather for a single completed well is accidental. Therefore, multiple completed wells can be selected to complete the division of the incident angle of the incident angle gather. The specific implementation is as follows:

[0087] Determine multiple completed wells, and obtain the initial incident angle gather of each completed well within the target time window for the target horizon; the initial incident angle gather of each completed well is used as the incident angle gather.

[0088] In practical applications, for all completed wells, obtain the near-well incident angle gather. Use the initial incident angle gathers obtained for each completed well as the incident angle gathers for subsequent incident angle division processing. After performing the incident angle division processing on the incident angle gathers for each completed well, the final incident angle division method can be determined by taking the average of the incident angle divisions of each completed well.

[0089] Step 204: Determine the amplitude characteristic distribution and waveform coefficient characteristic distribution of the incident angle gather within the target time window.

[0090] Specifically, after obtaining the incident angle gather of the completed well within the target time window for the target horizon as described above, the amplitude characteristic distribution and waveform coefficient characteristic distribution of the incident angle gather within the target time window can be determined. Among them, the amplitude characteristic distribution represents the variation relationship of the amplitude of the target horizon with the incident angle; the waveform coefficient characteristic distribution represents the variation relationship of the waveform correlation coefficient between any two adjacent seismic traces in the incident angle gather within the target time window. The change in the waveform correlation coefficient is also referred to as the change in time waveform correlation.

[0091] Based on this, after obtaining the incident angle gather of the completed well within the target time window for the target horizon as described above, AVO characteristic analysis can be performed on the target horizon. When performing AVO characteristic analysis, determine the amplitude characteristic distribution and waveform coefficient characteristic distribution of the incident angle gather within the target time window. Perform incident angle division on the incident angle gather in the amplitude dimension and waveform coefficient dimension.

[0092] Furthermore, the amplitude characteristic distribution represents the change in the relationship between the amplitude and the incident angle in the incident angle gather. Multiple sets of amplitude data can be collected, data pairs can be formed based on the corresponding relationship between the amplitude data and the incident angle, and an amplitude characteristic diagram can be drawn based on multiple sets of data pairs. The specific implementation is as follows:

[0093] Within the target time window, determine the corresponding relationship between the incident angles included in the incident angle gather and the amplitude data of the target horizon; generate an amplitude characteristic diagram based on the corresponding relationship, and determine the amplitude characteristic distribution in the amplitude characteristic diagram.

[0094] Based on this, within the target time window, collect the amplitude data and incident angles at each time point, determine the corresponding relationship between the incident angles included in the incident angle gather and the amplitude data of the target horizon. Generate an amplitude characteristic diagram based on the corresponding relationship, and determine the amplitude characteristic distribution of the change in the amplitude of the target horizon with the incident angle in the amplitude characteristic diagram. The amplitude characteristic diagram depicts the variation relationship of the amplitude with the incident angle.

[0095] For example, Figure 4 is a schematic diagram of the amplitude characteristic distribution of an incident angle gather division method provided by an embodiment of this specification. After determining the well drilling, select the incident angle gather L01 near the completed well W01. According to the target horizon determined in step one, determine the analysis time window as 1120 - 1150 ms, and conduct AVO characteristic analysis for this horizon, analyze the variation relationship between the amplitude of the target horizon and the incident angle, and draw an Figure 4 amplitude-incident angle crossplot as shown. In the amplitude-incident angle crossplot, the amplitude characteristic distribution of the variation of the amplitude of the target horizon with the incident angle can be clearly determined.

[0096] In summary, the correspondence between the incident angles included in the incident angle gather and the amplitude data of the target horizon generates an amplitude characteristic map, and the amplitude characteristic distribution of the variation of the amplitude of the target horizon with the incident angle is determined in the amplitude characteristic map. This is to facilitate subsequent division of the incident angle gather in the amplitude characteristic dimension based on the amplitude characteristic distribution.

[0097] Furthermore, the waveform coefficient characteristic distribution represents the correlation variation of adjacent traces in the waveform dimension in the incident angle gather. Based on the correspondence between the waveform correlation coefficient and the incident angle, a waveform coefficient characteristic distribution map is drawn. The specific implementation is as follows:

[0098] Determine at least two sets of adjacent traces in the incident angle gather associated with the target time window; generate a waveform coefficient characteristic distribution map based on the waveform correlation coefficients respectively corresponding to the at least two sets of adjacent traces, and determine the waveform coefficient characteristic distribution in the waveform coefficient characteristic distribution map.

[0099] Specifically, the adjacent traces are two adjacent seismic traces; the waveform correlation coefficient refers to the waveform correlation degree between two adjacent seismic traces; the waveform coefficient characteristic distribution map depicts the distribution of the relationship between the waveform coefficient and the incident angle within the target time window.

[0100] Based on this, determine at least two sets of adjacent traces in the incident angle gather associated with the target time window, and use the waveform correlation coefficient between the two seismic traces in each set of adjacent traces as the waveform correlation coefficient corresponding to the adjacent traces. According to the time sequence in the target time window, generate a waveform coefficient characteristic distribution map based on the waveform correlation coefficients respectively corresponding to the at least two sets of adjacent traces. Determine the waveform coefficient characteristic distribution representing the waveform correlation between two adjacent seismic traces in the incident angle gather within the target time window in the waveform coefficient characteristic distribution map.

[0101] Continuing with the above example, Figure 5It is a schematic diagram of the waveform coefficient feature distribution of an incident angle gather division method provided by an embodiment of this specification. Correlation analysis is performed on the incident angle gather L01 near the completed well W01, and the analysis time window is 1120 - 1150 ms. Calculate the waveform correlation coefficient between two adjacent traces within this time window, and draw a correlation coefficient - incident angle crossplot as shown in Figure 5 . In the correlation coefficient - incident angle crossplot, the waveform coefficient feature distribution of the target horizon changing with the incident angle can be clearly determined.

[0102] In summary, a waveform coefficient feature distribution map is generated based on the waveform correlation coefficients respectively corresponding to at least two groups of adjacent traces. Determine the waveform coefficient feature distribution in the waveform coefficient feature distribution map. So as to facilitate subsequent division of the incident angle gather in the waveform dimension based on the waveform coefficient feature distribution.

[0103] Step 206: Divide the incident angle gather in the amplitude feature dimension according to the amplitude feature distribution, generate first gather division information based on the amplitude division result, and divide the incident angle gather in the waveform dimension according to the waveform coefficient feature distribution, generate second gather division information based on the waveform division result.

[0104] Specifically, after determining the amplitude feature distribution and waveform coefficient feature distribution of the incident angle gather within the target time window as described above, the incident angle gather can be divided in the amplitude feature dimension according to the amplitude feature distribution, generate first gather division information based on the amplitude division result, and divide the incident angle gather in the waveform dimension according to the waveform coefficient feature distribution, generate second gather division information based on the waveform division result. Among them, the first gather division information refers to the division result of dividing the incident angles of the incident angle gather in the amplitude feature dimension; the first gather division information can be the incident angle range corresponding to the amplitude feature dimension, and the incident angles of the incident angle gather are divided into a near - trace incident angle range, a middle - trace incident angle range, and a far - trace incident angle range in the amplitude feature dimension. According to the near - trace incident angle range, the near - trace and middle - trace nodes in the amplitude feature dimension can be determined, and according to the middle - trace incident angle range, the middle - trace and far - trace nodes in the amplitude feature dimension can be determined. The second gather division information refers to the division result of dividing the incident angles of the incident angle gather in the waveform coefficient dimension; correspondingly, the second gather division information can be the incident angle range corresponding to the waveform dimension, and the incident angles of the incident angle gather are divided into a near - trace incident angle range, a middle - trace incident angle range, and a far - trace incident angle range in the waveform dimension. According to the near - trace incident angle range, the near - trace and middle - trace nodes in the waveform dimension can be determined, and according to the middle - trace incident angle range, the middle - trace and far - trace nodes in the waveform dimension can be determined.

[0105] Based on this, after determining the amplitude characteristic distribution and waveform coefficient characteristic distribution of the incident angle gather within the target time window as described above, the incident angle gather is divided in the amplitude characteristic dimension according to the amplitude characteristic distribution, and the first gather division information is generated according to the amplitude division result. The first gather division information is the division result of the incident angle division of the incident angle gather in the amplitude characteristic dimension, and what is obtained is the division range of the incident angles in the incident angle gather. The incident angle gather is divided in the waveform dimension according to the waveform coefficient characteristic distribution, and the second gather division information is generated according to the waveform division result. The second gather division information is the division result of the incident angle division of the incident angle gather in the waveform coefficient dimension, and what is obtained is the division range of the incident angles in the incident angle gather.

[0106] Further, the amplitude characteristic distribution represents the variation of the amplitude of the target horizon with the incident angle. Determine the amplitude mutation points in the line graph of the amplitude characteristic distribution, and the amplitude mutation points can be used as the division points of the incident angle. The specific implementation is as follows:

[0107] Determine the amplitude mutation points in the amplitude characteristic distribution, and determine the first incident angle information corresponding to the amplitude mutation points based on the amplitude characteristic distribution; divide the incident angle gather based on the first incident angle information.

[0108] Specifically, the amplitude mutation point refers to the point in the amplitude characteristic distribution where the amplitude changes significantly between two adjacent incident angles; the information of the incident angle when the amplitude starts to change significantly is the first incident angle information. The first incident angle information refers to the angle of the incident angle when the amplitude starts to change significantly. The first incident angle information corresponds to at least one incident angle.

[0109] Based on this, according to the principle of uniform distribution of incident angles, determine at least one amplitude mutation point in the amplitude characteristic distribution. Determine the first incident angle information corresponding to each amplitude mutation point based on the amplitude characteristic distribution. Divide the incident angles in the incident angle gather based on the first incident angle information, and divide the incident angles in the incident angle gather into a near - channel incident angle range, a middle - channel incident angle range, and a far - channel incident angle range in the amplitude characteristic dimension. The near - channel and middle - channel nodes in the amplitude characteristic dimension can be determined according to the near - channel incident angle range, and the middle - channel and far - channel nodes in the amplitude characteristic dimension can be determined according to the middle - channel incident angle range.

[0110] Continuing with the above example, in Figure 4 the amplitude - incident angle cross - plot as shown, determine that the points corresponding to the incident angle of 15° and the incident angle of 25° are amplitude mutation points. Then the incident angle gather L01 is divided into 3 regions by two amplitude mutation points in the amplitude characteristic dimension: the near - channel incident angle range of 0° - 15°, the middle - channel incident angle range of 16° - 25°, and the far - channel incident angle range of 26° - 35°. Then the near - channel and middle - channel node is 15°, and the middle - channel and far - channel node is 25°.

[0111] In summary, according to the principle of uniform distribution of the incident angle, at least one amplitude mutation point is determined in the amplitude characteristic distribution. Based on the first incident angle information corresponding to at least one amplitude mutation point, the incident angles in the incident angle gather are divided, so as to realize the division of the incident angles in the incident angle gather according to the amplitude data.

[0112] Furthermore, the waveform coefficient characteristic distribution represents the change of the correlation between the waveforms in the time windows of two adjacent seismic traces in the incident angle gather. Determine the waveform mutation point in the line graph of the waveform coefficient characteristic distribution, and the waveform mutation point can be used as the division point of the incident angle. The specific implementation is as follows:

[0113] Determine the waveform mutation point in the waveform coefficient characteristic distribution, and determine the second incident angle information corresponding to the waveform mutation point based on the waveform coefficient characteristic distribution; divide the incident angle gather based on the second incident angle information.

[0114] Specifically, the waveform mutation point refers to the point where the waveform coefficient changes greatly between two adjacent incident angles in the waveform coefficient characteristic distribution; the information of the incident angle when the waveform coefficient begins to change greatly is the second incident angle information. The second incident angle information refers to the angle of the incident angle when the waveform coefficient begins to change greatly. The second incident angle information corresponds to at least one incident angle.

[0115] Based on this, according to the principle of uniform distribution of the incident angle, at least one waveform mutation point is determined in the waveform coefficient characteristic distribution. Determine the second incident angle information corresponding to each waveform mutation point based on the waveform coefficient characteristic distribution. Divide the incident angles in the incident angle gather based on the second incident angle information, and divide the incident angles of the incident angle gather into a near-trace incident angle range, a middle-trace incident angle range, and a far-trace incident angle range in the waveform dimension. According to the near-trace incident angle range, the near-trace and middle-trace nodes in the waveform dimension can be determined, and according to the middle-trace incident angle range, the middle-trace and far-trace nodes in the waveform dimension can be determined.

[0116] Continuing with the above example, in Figure 5 the shown correlation coefficient-incident angle cross plot, determine that the points corresponding to the incident angles of 12° and 26° are waveform mutation points. Then the incident angle gather L01 is divided into 3 regions in the waveform dimension by two amplitude mutation points: the near-trace incident angle range of 0° to 12°, the middle-trace incident angle range of 13° to 26°, and the far-trace incident angle range of 27° to 35°. Then the near-trace and middle-trace nodes are 12°, and the middle-trace and far-trace nodes are 26°.

[0117] In summary, according to the principle of uniform distribution of the incident angle, at least one waveform mutation point is determined in the waveform coefficient characteristic distribution. Divide the incident angles in the incident angle gather based on the second incident angle information corresponding to at least one waveform mutation point, so as to realize the division of the incident angles in the incident angle gather according to the waveform coefficient.

[0118] Step 208: Generate target partitioning information for the angle-of-incidence gather based on the first gather partitioning information and the second gather partitioning information, where the target partitioning information is used for prestack inversion.

[0119] Specifically, after partitioning the angle-of-incidence gather in the amplitude feature dimension according to the amplitude feature distribution, generating the first gather partitioning information based on the amplitude partitioning result, and partitioning the angle-of-incidence gather in the waveform dimension according to the waveform coefficient feature distribution, generating the second gather partitioning information based on the waveform partitioning result, the target partitioning information for the angle-of-incidence gather can be generated based on the first gather partitioning information and the second gather partitioning information. The target partitioning information is used for prestack inversion and is the partitioning information for the angle of incidence of the angle-of-incidence gather obtained after integrating the first gather partitioning information and the second gather partitioning information.

[0120] Based on this, after partitioning the angle-of-incidence gather in the amplitude feature dimension according to the amplitude feature distribution, generating the first gather partitioning information based on the amplitude partitioning result, and partitioning the angle-of-incidence gather in the waveform dimension according to the waveform coefficient feature distribution, generating the second gather partitioning information based on the waveform partitioning result, integrate the first gather partitioning information and the second gather partitioning information to generate the target partitioning information for the angle-of-incidence gather. The target partitioning information corresponds to the partitioning information for the angle of incidence of the angle-of-incidence gather and is used for subsequent prestack inversion.

[0121] In practical applications, for all completed wells, select the near-wellbore angle-of-incidence gathers, repeat Steps 202 to 208 to obtain the final results of the angle-of-incidence partitioning for all near-wellbore angle-of-incidence gathers of the completed wells, and then take the average of the partitioning results of all wells as the final solution for the angle-of-incidence partitioning of the angle-of-incidence gather.

[0122] Continuing with the above example, for the other two completed wells W02 and W03 among the 3 completed wells, select the near-wellbore angle-of-incidence gathers L02 and L03 respectively to obtain the final results of the angle-of-incidence partitioning for all near-wellbore angle-of-incidence gathers of the completed wells: L02_N = 12°, L02_F = 26.5°; L03_N = 13°, L03_F = 25°. Then take the average of the partitioning results of all wells as the final result of the angle-of-incidence partitioning of the angle-of-incidence gather: N = 1 / 3(L01_N + L02_N + L03_N) = 12.8°; F = 1 / 3(L01_F + L02_F + L03_F) = 25.7°. Therefore, the final angle-of-incidence partitioning results are 0° - 12.8°, 12.8° - 26.5°, 26.5° - 35°. Since the angle of incidence cannot be set as a decimal, the partitioning scheme is approximately 0° - 13°, 14° - 27°, 28° - 35°.

[0123] Furthermore, considering that the incident angle gather is divided by the incident angle in the amplitude feature dimension and the waveform dimension respectively, and a division method is required for the division of the incident angle gather, and the first gather division information includes three angular ranges: the near trace, the middle trace, and the far trace. Therefore, it is necessary to determine the target division information including different angular ranges based on the first gather division information and the second gather division information. The specific implementation is as follows:

[0124] Determine the first near trace incident angle information, the first middle trace incident angle information, and the first far trace incident angle information corresponding to the incident angle gather based on the first gather division information, and determine the second near trace incident angle information, the second middle trace incident angle information, and the second far trace incident angle information corresponding to the incident angle gather based on the second gather division information; determine the target near trace incident angle information corresponding to the first near trace incident angle information and the second near trace incident angle information, the target middle trace incident angle information corresponding to the first middle trace incident angle information and the second middle trace incident angle information, and the target far trace incident angle information corresponding to the first far trace incident angle information and the second far trace incident angle information; and form the target division information from the target near trace incident angle information, the target middle trace incident angle information, and the target far trace incident angle information.

[0125] Specifically, the first near trace incident angle information refers to the near trace incident angle range of the incident angle of the incident angle gather in the amplitude feature dimension; the first middle trace incident angle information refers to the middle trace incident angle range of the incident angle of the incident angle gather in the amplitude feature dimension; the first far trace incident angle information refers to the far trace incident angle range of the incident angle of the incident angle gather in the amplitude feature dimension. The second near trace incident angle information refers to the near trace incident angle range of the incident angle of the incident angle gather in the waveform dimension; the second middle trace incident angle information refers to the middle trace incident angle range of the incident angle of the incident angle gather in the waveform dimension; the second far trace incident angle information refers to the far trace incident angle range of the incident angle of the incident angle gather in the waveform dimension; the target near trace incident angle information is determined by calculating the mean between the incident angles corresponding to the first near trace incident angle information and the second near trace incident angle information; correspondingly, the target middle trace incident angle information is determined by calculating the mean between the incident angles corresponding to the first middle trace incident angle information and the second middle trace incident angle information; and the target far trace incident angle information is determined by calculating the mean between the incident angles corresponding to the first far trace incident angle information and the second far trace incident angle information.

[0126] Based on this, the first near-channel incident angle information, the first middle-channel incident angle information and the first far-channel incident angle information corresponding to the incident angle track set are determined based on the amplitude mutation point corresponding to the first track set division information, and the second near-channel incident angle information, the second middle-channel incident angle information and the second far-channel incident angle information corresponding to the incident angle track set are determined based on the waveform mutation point corresponding to the second track set division information. The target near-channel incident angle information is calculated based on the incident angle corresponding to the first near-channel incident angle information and the incident angle corresponding to the second near-channel incident angle information, the target middle-channel incident angle information is calculated based on the incident angle corresponding to the first middle-channel incident angle information and the incident angle corresponding to the second middle-channel incident angle information, and the target far-channel incident angle information is calculated based on the incident angle corresponding to the first far-channel incident angle information and the incident angle corresponding to the second far-channel incident angle information. The target division information is composed of the target near-channel incident angle information, the target middle-channel incident angle information and the target far-channel incident angle information.

[0127] Using the above example, after the amplitude feature dimension has been determined to have a near-path incident angle range of 0° to 15°, a mid-path incident angle range of 16° to 25°, and a far-path incident angle range of 26° to 35°, the near-path and mid-path nodes are 15°, and the mid-path and far-path nodes are 25°, and the waveform dimension has been determined to have a near-path incident angle range of 0° to 12°, a mid-path incident angle range of 13° to 26°, and a far-path incident angle range of 27° to 35°, the near-path and mid-path nodes are 12°, and the mid-path and far-path nodes are 26°, the near-path and mid-path nodes of the amplitude feature dimension and the waveform dimension, as well as the mid-path and far-path nodes, can be calculated respectively. The average of the near-path and mid-path nodes 15° of the amplitude feature dimension and the near-path and mid-path nodes 12° of the waveform dimension is calculated to obtain 13.5°. The mean of the mid-path and far-path nodes 25° in the amplitude feature dimension and the mid-path and far-path nodes 26° in the waveform dimension is calculated to obtain 25.5°. Then 13.5° and 25.5° are two incident angle division points. Based on the two incident angle division points, the target near-path incident angle information 0°~13.5°, the target mid-path incident angle information 13.5°~25.5° and the target far-path incident angle information 25.5°~35° can be determined. The target division information is composed of the target near-path incident angle information, the target mid-path incident angle information and the target far-path incident angle information.

[0128] In summary, the target division information is composed of the target near-track incident angle information, the target mid-track incident angle information and the target far-track incident angle information, which integrates the incident angle information of the amplitude feature dimension and the incident angle information of the waveform dimension, thereby realizing the accurate and quantitative division of the incident angle of the incident angle gather.

[0129] Furthermore, since the special channel is caused by the error caused by the average calculation of the incident angle gather, it is also necessary to remove the special channel data in the incident angle gather. The special channel is the target channel in the incident angle gather. The specific implementation is as follows:

[0130] Generate the initial partitioning information of the incident angle gather based on the first gather partitioning information and the second gather partitioning information; determine target traces in the incident angle gather based on the initial partitioning information, and update the initial partitioning information to intermediate partitioning information by removing the target traces; determine the corrected incident angle step size, and determine the central trace in the incident angle gather based on the intermediate partitioning information; determine at least two calculation traces in the incident angle gather based on the incident angle step size, and calculate the correction values corresponding to the central trace and the at least two calculation traces respectively; determine at least two corrected amplitude values based on the at least two correction values and the at least two amplitude values corresponding to the incident angle gather; update the initial amplitude values included in the intermediate partitioning information based on the at least two corrected amplitude values to obtain the target partitioning information.

[0131] Specifically, the initial partitioning information refers to the maximum amplitude value difference, and the maximum and minimum values of the waveform correlation coefficient. Use the maximum amplitude value difference, the maximum and minimum values of the waveform correlation coefficient as thresholds to screen the seismic traces in the incident angle gather. The seismic traces that are greater than the maximum amplitude value difference and greater than the maximum value or less than the minimum value of the waveform correlation coefficient are the target traces; the intermediate partitioning information is the incident angle partitioning information obtained after removing the target traces. The corrected incident angle step size is usually set to 1°; the central trace refers to the central incident angle value of each incident angle range; the calculation traces refer to each seismic trace included in the incident angle gather; the at least two amplitude values corresponding to the incident angle gather are the amplitude values of the actual seismic traces.

[0132] In practical applications, based on the final incident angle partitioning result of the incident angle gather, analyze the maximum amplitude value difference and the correlation coefficient between adjacent traces at the target horizon within the partitioned incident angle range for each incident angle gather. Since the special traces are caused by the error in the average calculation of the incident angle gather partitioning, they are mainly distributed at both ends of the incident angle partitioning range. Calculate the maximum amplitude value difference and the correlation coefficient for 80% of the seismic traces in the middle part after the incident angle gather is partitioned, and take the maximum and minimum values of the maximum amplitude value difference and the correlation coefficient as thresholds for screening. The seismic traces outside the thresholds are removed as special traces and do not participate in the stacking. As Figure 6 shown, the seismic traces corresponding to the incident angles of 13° and 27° are used as the special traces in the incident angle gather. In addition, after removing the special traces and performing AVO difference correction, the seismic traces within each incident angle range can be stacked and averaged to obtain the final angle-separated stacked seismic data volume.

[0133] Forward calculation is performed using the shear wave velocity, compressional wave velocity, and density obtained from well logging, along with the seismic wavelet, to obtain the incident angle gather of forward simulation beside all completed wells. Select one of the wells, and according to the division result of the incident angle, take the central incident angle value within each division range of the incident angle as the standard, which is called the central trace. Determine the correction incident angle step size of 1°, calculate the amplitude ratio between the central trace and all traces, that is, the correction value, and form a statistical table of the incident angle difference and the correction value. According to the above calculation process, calculate the correction value for all completed wells, and take the average of the correction values with the same incident angle difference as the final result. Correct the amplitude values of all gathers according to this result to obtain the zero-offset gather where the amplitude within each incident angle range is not affected by the AVO effect.

[0134] Continuing with the above example, take the incident angle gather within the range of 0° to 13° of a wellbore gather as an example to illustrate the calculation process and results of AVO difference correction. First, perform AVO forward modeling to obtain the forward incident angle gather of the target layer within the range of 0° to 13°. Since this incident angle gather is a theoretical calculation, it only includes the influence of the incident angle on the amplitude value. According to this forward gather, the variation of the amplitude value at different incident angles can be determined, and further, the actual incident angle gather can be corrected based on this variation. According to the AVO forward modeling result, read the amplitude values of the forward gather at the target layer, take the 7th trace as the central trace, and perform division operations with the remaining 12 traces respectively to determine the ratio between each trace and the central trace, that is, the correction value. Then read the amplitude values of the actual seismic traces, and perform multiplication operations between the amplitude values at each incident angle and the correction value to obtain the amplitude values of the corrected gather, that is, the final amplitude values after eliminating the influence of the AVO effect. The following Table 1 is the statistical table of the incident angle difference and the correction value.

[0135]

[0136] Table 1

[0137] In summary, by removing the target traces in the incident angle gather and performing AVO difference correction on the incident angle gather, the influence of special traces in the incident angle gather is eliminated, and the incident angles in the incident angle gather are accurately and quantitatively divided.

[0138] In one embodiment of this specification, for a target horizon, an incident angle gather of a completed well is obtained within a target time window. The amplitude characteristic distribution and waveform coefficient characteristic distribution of the incident angle gather within the target time window are determined. The incident angle gather is divided in the amplitude characteristic dimension according to the amplitude characteristic distribution, and first gather division information is generated based on the amplitude division result. Also, the incident angle gather is divided in the waveform dimension according to the waveform coefficient characteristic distribution, and second gather division information is generated based on the waveform division result. The target division information of the incident angle gather is generated based on the first gather division information and the second gather division information, realizing an accurate and quantitative division of the incident angles of the incident angle gather, so as to facilitate the subsequent accurate implementation of prestack inversion work. This provides a basis for the exploration and development of lithologic-stratigraphic oil and gas reservoirs and unconventional oil and gas.

[0139] The following combines the attached Figure 7 , taking the application of the incident angle gather division method provided in this specification in incident angle division before prestack inversion as an example, to further illustrate the incident angle gather division method. Among them, Figure 7 FIG. shows the processing flow chart of an incident angle gather division method provided in one embodiment of this specification, which specifically includes the following steps.

[0140] Step 702: For a target horizon, an incident angle gather of a completed well is obtained within an analysis time window.

[0141] Step 704: The incident angle gather of the completed well is divided in the amplitude characteristic dimension to obtain first division information.

[0142] Select a completed well A, and obtain the incident angle gather LA near the completed well A. Determine the analysis time window according to the target horizon. The analysis time window is determined to be able to completely contain the target horizon and be greater than 1 / 2 of a cycle. Conduct AVO characteristic analysis, that is, analyze the relationship between the amplitude of the target horizon and the incident angle, and draw an amplitude-incident angle crossplot. According to the principle of taking into account the uniform distribution of incident angles at the mutation points of the amplitude broken line in the figure, the incident angles of the incident angle gather are initially divided to form the division result 1 of the incident angle gather LA.

[0143] Step 706: The incident angle gather of the completed well is divided in the waveform correlation dimension to obtain second division information.

[0144] For the incident angle gather LA, calculate the correlation between the waveforms within the time windows of two adjacent seismic traces, and draw a correlation coefficient-incident angle crossplot. According to the principle of taking into account the uniform distribution of incident angles at the mutation points of the correlation coefficient broken line in the figure, the incident angles of the incident angle gather are divided to form the division result 2 of the incident angle gather LA.

[0145] Step 708: Determine the incident angle division information of the completed well based on the first division information and the second division information.

[0146] The average of division result 1 and division result 2 is taken as the final result of the incident angle division of the wellside incident angle gather of the completed well A.

[0147] In practical applications, there may be multiple completed wells. For all completed wells, wellside incident angle gathers are selected, and steps 704 to 706 are repeated to obtain the final result of the incident angle division of all wellside incident angle gathers. Then, the average of all the division results is taken as the final solution of the incident angle division of the incident angle gathers.

[0148] Step 710: Determine at least one incident angle gather to be processed according to the incident angle division information, and remove special traces in the incident angle gather to be processed to obtain an initial incident angle gather.

[0149] Step 712: Perform AVO difference correction on the initial incident angle gather to obtain the target incident angle gather.

[0150] Step 714: Calculate the seismic traces within each incident angle range corresponding to the target incident angle gather to obtain seismic volume data.

[0151] The calculation of the seismic traces within each incident angle range corresponding to the target incident angle gather is to perform the addition and average calculation on the seismic traces within each incident angle range corresponding to the target incident angle gather, so as to obtain the final angle-stacked seismic data volume.

[0152] The amplitude values ​​and waveform similarity characteristics between different seismic traces are analyzed on the incident angle gather, and the optimal incident angle division scheme is determined according to the distribution of amplitude values ​​and waveform correlation coefficients, and the best angle-divided stacking data volume is further obtained. This has important practical significance for improving the reliability of pre-stack inversion results and increasing the success rate of oil and gas field exploration and development.

[0153] Corresponding to the above method embodiment, this specification also provides an incident angle gather division device embodiment, Figure 8 FIG. 2 shows a schematic diagram of the structure of an incident angle gather division device provided by an embodiment of the present specification. Figure 8 As shown, the device comprises:

[0154] An acquisition module 802 is configured to acquire incident angle gathers of the completed well within a target time window for a target layer;

[0155] A determination module 804 is configured to determine an amplitude characteristic distribution and a waveform coefficient characteristic distribution of the incident angle gather within the target time window;

[0156] A partitioning module 806, configured to partition the incident angle gather in the amplitude feature dimension according to the amplitude feature distribution, generate first gather partitioning information according to the amplitude partitioning result, and partition the incident angle gather in the waveform dimension according to the waveform coefficient feature distribution, and generate second gather partitioning information according to the waveform partitioning result;

[0157] A generating module 808, configured to generate target partitioning information of the incident angle gather based on the first gather partitioning information and the second gather partitioning information, wherein the target partitioning information is used for prestack inversion.

[0158] In an optional embodiment, the determining module 804 is further configured to:

[0159] Within the target time window, determine the correspondence between the incident angles included in the incident angle gather and the amplitude data of the target horizon;

[0160] Generate an amplitude feature map based on the correspondence, and determine the amplitude feature distribution in the amplitude feature map.

[0161] In an optional embodiment, the determining module 804 is further configured to:

[0162] Determine at least two sets of adjacent traces in the incident angle gather associated with the target time window;

[0163] Generate a waveform coefficient feature distribution map based on the waveform correlation coefficients respectively corresponding to the at least two sets of adjacent traces, and determine the waveform coefficient feature distribution in the waveform coefficient feature distribution map.

[0164] In an optional embodiment, the partitioning module 806 is further configured to:

[0165] Determine amplitude mutation points in the amplitude feature distribution, and determine first incident angle information corresponding to the amplitude mutation points based on the amplitude feature distribution;

[0166] Partition the incident angle gather based on the first incident angle information.

[0167] In an optional embodiment, the partitioning module 806 is further configured to:

[0168] Determine waveform mutation points in the waveform coefficient feature distribution, and determine second incident angle information corresponding to the waveform mutation points based on the waveform coefficient feature distribution;

[0169] Partition the incident angle gather based on the second incident angle information.

[0170] In an optional embodiment, the generating module 808 is further configured to:

[0171] Determine the first near-offset incident angle information, the first mid-offset incident angle information, and the first far-offset incident angle information corresponding to the incident angle gather based on the first gather division information, and determine the second near-offset incident angle information, the second mid-offset incident angle information, and the second far-offset incident angle information corresponding to the incident angle gather based on the second gather division information;

[0172] Determine the target near-offset incident angle information corresponding to the first near-offset incident angle information and the second near-offset incident angle information, the target mid-offset incident angle information corresponding to the first mid-offset incident angle information and the second mid-offset incident angle information, and the target far-offset incident angle information corresponding to the first far-offset incident angle information and the second far-offset incident angle information;

[0173] The target division information is composed of the target near-offset incident angle information, the target mid-offset incident angle information, and the target far-offset incident angle information.

[0174] In an alternative embodiment, the obtaining module 802 is further configured to:

[0175] Determine a plurality of completed wells, and obtain the initial incident angle gather of each completed well within the target time window for the target horizon;

[0176] The initial incident angle gather of each completed well is used as the incident angle gather.

[0177] In an alternative embodiment, the generating module 808 is further configured to:

[0178] Generate the initial division information of the incident angle gather based on the first gather division information and the second gather division information;

[0179] Determine the target traces in the incident angle gather based on the initial division information, and update the initial division information to the intermediate division information by removing the target traces;

[0180] Determine the correction incident angle step, and determine the central trace in the incident angle gather based on the intermediate division information;

[0181] Determine at least two calculation traces in the incident angle gather based on the incident angle step, and calculate the correction values corresponding to the central trace and the at least two calculation traces respectively;

[0182] Determine at least two correction amplitude values based on the at least two correction values and the at least two amplitude values corresponding to the incident angle gather;

[0183] Update the initial amplitude values included in the intermediate division information based on the at least two correction amplitude values to obtain the target division information.

[0184] In one embodiment of the present specification, the incident angle gather of the completed well is obtained for the target horizon within the target time window. The amplitude characteristic distribution and the waveform coefficient characteristic distribution of the incident angle gather within the target time window are determined. The incident angle gather is divided in the amplitude characteristic dimension according to the amplitude characteristic distribution, and the first gather division information is generated according to the amplitude division result. In addition, the incident angle gather is divided in the waveform dimension according to the waveform coefficient characteristic distribution, and the second gather division information is generated according to the waveform division result. The target division information of the incident angle gather is generated based on the first gather division information and the second gather division information, so as to achieve accurate and quantitative division of the incident angles of the incident angle gather, facilitating subsequent accurate pre-stack inversion work and providing a basis for the exploration and development of lithologic-stratigraphic oil and gas reservoirs and unconventional oil and gas.

[0185] The above is a schematic solution of an incident angle gather division device according to this embodiment. It should be noted that the technical solution of this incident angle gather division device and the technical solution of the above incident angle gather division method belong to the same concept. For the details not described in the technical solution of the incident angle gather division device, reference can be made to the description of the technical solution of the above incident angle gather division method.

[0186] Figure 9 FIG. shows a structural block diagram of a computing device 900 according to an embodiment of the present specification. The components of the computing device 900 include, but are not limited to, a memory 910 and a processor 920. The processor 920 is connected to the memory 910 through a bus 930, and a database 950 is used to store data.

[0187] The computing device 900 further includes an access device 940, which enables the computing device 900 to communicate via one or more networks 960. Examples of such networks include the Public Switched Telephone Network (PSTN), Local Area Network (LAN), Wide Area Network (WAN), Personal Area Network (PAN), or a combination of communication networks such as the Internet. The access device 940 may include one or more of any type of wired or wireless network interfaces (e.g., network interface controller (NIC)), such as IEEE 802.11 Wireless Local Area Network (WLAN) wireless interface, Worldwide Interoperability for Microwave Access (Wi-MAX) interface, Ethernet interface, Universal Serial Bus (USB) interface, cellular network interface, Bluetooth interface, Near Field Communication (NFC).

[0188] In one embodiment of the present specification, the above components of the computing device 900 and Figure 9 other components not shown may also be connected to each other, for example, via a bus. It should be understood that Figure 9 the block diagram of the computing device shown is for illustrative purposes only and is not a limitation on the scope of the present specification. Those skilled in the art can add or replace other components as needed.

[0189] The computing device 900 can be any type of stationary or mobile computing device, including mobile computers or mobile computing devices (e.g., tablet computers, personal digital assistants, laptop computers, notebook computers, netbooks, etc.), mobile phones (e.g., smartphones), wearable computing devices (e.g., smartwatches, smart glasses, etc.) or other types of mobile devices, or stationary computing devices such as desktop computers or personal computers (PCs). The computing device 900 can also be a mobile or stationary server.

[0190] Wherein, the processor 920 is used to execute the following computer-executable instructions, and when the computer-executable instructions are executed by the processor, the steps of the above-mentioned incident angle gather partitioning method are implemented.

[0191] The above is a schematic solution of a computing device according to this embodiment. It should be noted that the technical solution of this computing device and the technical solution of the above-mentioned incident angle gather division method belong to the same concept. For the detailed content not described in the technical solution of the computing device, reference can be made to the description of the technical solution of the above-mentioned incident angle gather division method.

[0192] An embodiment of this specification also provides a computer-readable storage medium storing computer-executable instructions, which, when executed by a processor, implement the steps of the above-mentioned incident angle gather division method.

[0193] The above is a schematic solution of a computer-readable storage medium according to this embodiment. It should be noted that the technical solution of this storage medium and the technical solution of the above-mentioned incident angle gather division method belong to the same concept. For the detailed content not described in the technical solution of the storage medium, reference can be made to the description of the technical solution of the above-mentioned incident angle gather division method.

[0194] An embodiment of this specification also provides a computer program product including a computer program or instructions, which, when executed by a processor, implement the steps of the above-mentioned incident angle gather division method.

[0195] The above is a schematic solution of a computer program product according to this embodiment. It should be noted that the technical solution of this computer program product and the technical solution of the above-mentioned incident angle gather division method belong to the same concept. For the detailed content not described in the technical solution of the computer program product, reference can be made to the description of the technical solution of the above-mentioned incident angle gather division method.

[0196] The above describes specific embodiments of this specification. Other embodiments are within the scope of the appended claims. In some cases, the actions or steps recited in the claims may be performed in a different order than in the embodiments and still achieve the desired result. Additionally, the processes depicted in the figures do not necessarily require the particular order or sequential order shown to achieve the desired result. In certain embodiments, multitasking and parallel processing are also possible or may be advantageous.

[0197] The computer instructions include computer program code, which may be in the form of source code, object code, executable files or some intermediate forms, etc. The computer-readable medium may include: any entity or device capable of carrying the computer program code, recording medium, USB flash drive, mobile hard disk, magnetic disk, optical disk, computer memory, read-only memory (ROM), random access memory (RAM), electrical carrier signal, telecommunication signal, and software distribution medium, etc. It should be noted that the content included in the computer-readable medium can be appropriately increased or decreased according to the requirements of patent practice. For example, in some regions, according to patent practice, the computer-readable medium does not include electrical carrier signals and telecommunication signals.

[0198] It should be noted that for the foregoing method embodiments, for the sake of simplicity of description, they are all expressed as a series of action combinations. However, those skilled in the art should know that the embodiments of this specification are not limited by the described action sequence, because according to the embodiments of this specification, some steps can be performed in other sequences or simultaneously. Secondly, those skilled in the art should also know that the embodiments described in the specification are all preferred embodiments, and the actions and modules involved are not necessarily essential for the embodiments of this specification.

[0199] In the above embodiments, the descriptions of the respective embodiments have their own emphases. For the parts not detailed in a certain embodiment, reference can be made to the relevant descriptions of other embodiments.

[0200] The preferred embodiments of this specification disclosed above are only used to help explain this specification. The optional embodiments do not elaborate on all details and do not limit the invention to the specific embodiments described. Obviously, many modifications and variations can be made according to the content of the embodiments of this specification. This specification selects and specifically describes these embodiments to better explain the principles and practical applications of the embodiments of this specification, so that those skilled in the art can well understand and utilize this specification.

Claims

1. A method for dividing an incident angle gather, characterized in that: include: Obtain the incident angle gathers of the completed well within the target time window for the target layer; Determine the amplitude characteristic distribution and waveform coefficient characteristic distribution of the incident angle gather within the target time window, wherein the waveform coefficient characteristic distribution represents the change of the waveform correlation between any two adjacent seismic traces in the incident angle gather within the target time window; The incident angle gathers are divided in the amplitude characteristic dimension according to the amplitude mutation points in the amplitude characteristic distribution, and first gather division information including a near-path incident angle range, a middle-path incident angle range, and a far-path incident angle range under the amplitude characteristic dimension is generated according to the amplitude division result; and the incident angle gathers are divided in the waveform dimension according to the waveform mutation points in the waveform coefficient characteristic distribution, and second gather division information including a near-path incident angle range, a middle-path incident angle range, and a far-path incident angle range is generated according to the waveform division result; Determine first near-path incident angle information, first middle-path incident angle information and first far-path incident angle information corresponding to the incident angle gather based on the first gather division information, and determine second near-path incident angle information, second middle-path incident angle information and second far-path incident angle information corresponding to the incident angle gather based on the second gather division information; Determine target near-path incident angle information corresponding to the first near-path incident angle information and the second near-path incident angle information, target mid-path incident angle information corresponding to the first mid-path incident angle information and the second mid-path incident angle information, and target far-path incident angle information corresponding to the first far-path incident angle information and the second far-path incident angle information; The target near-path incident angle information, the target mid-path incident angle information and the target far-path incident angle information constitute target division information, wherein the target division information is used for prestack inversion.

2. The incident angle gather division method according to claim 1, characterized in that: The determining of the amplitude characteristic distribution of the incident angle gather within the target time window comprises: Determining, within the target time window, a corresponding relationship between the incident angle contained in the incident angle gather and the amplitude data of the target layer; An amplitude feature map is generated based on the corresponding relationship, and the amplitude feature distribution is determined in the amplitude feature map.

3. The incident angle gather division method according to claim 1, characterized in that: Determining the waveform coefficient characteristic distribution of the incident angle gather within the target time window includes: Determining at least two groups of adjacent traces in the incident angle gather associated with the target time window; A waveform coefficient characteristic distribution map is generated based on the waveform correlation coefficients respectively corresponding to the at least two groups of adjacent tracks, and the waveform coefficient characteristic distribution is determined in the waveform coefficient characteristic distribution map.

4. The incident angle gather division method according to claim 1, characterized in that: The dividing the incident angle gathers in the amplitude feature dimension according to the amplitude feature distribution includes: Determining an amplitude mutation point in the amplitude characteristic distribution, and determining first incident angle information corresponding to the amplitude mutation point based on the amplitude characteristic distribution; The incident angle gathers are divided based on the first incident angle information.

5. The incident angle gather division method according to claim 1, characterized in that: The dividing the incident angle gathers according to the waveform coefficient characteristic distribution in the waveform dimension includes: Determining a waveform mutation point in the waveform coefficient characteristic distribution, and determining second incident angle information corresponding to the waveform mutation point based on the waveform coefficient characteristic distribution; The incident angle gathers are divided based on the second incident angle information.

6. The method for dividing the incident angle gathers according to claim 1, characterized in that: In the case where there are multiple completed wells, obtaining the incident angle gathers of the completed wells within the target time window for the target layer includes: Determine a plurality of completed wells, and obtain an initial incident angle gather of each completed well within the target time window for the target layer; The initial incident angle gather of each completed well is used as the incident angle gather.

7. The incident angle gather division method according to claim 1, characterized in that: The generating the target division information of the incident angle gather based on the first gather division information and the second gather division information comprises: Generating initial division information of the incident angle gather based on the first gather division information and the second gather division information; Determine a target track in the incident angle track gather based on the initial division information, and update the initial division information to intermediate division information by eliminating the target track; determining a corrected incident angle step size, and determining a central track in the incident angle gather based on the intermediate division information; Determine at least two calculation traces in the incident angle trace gather based on the incident angle step length, and calculate correction values ​​corresponding to the central trace and the at least two calculation traces respectively; Determining at least two correction amplitude values ​​based on at least two correction values ​​and at least two amplitude values ​​corresponding to the incident angle gather; The initial amplitude value included in the intermediate division information is updated based on the at least two corrected amplitude values ​​to obtain the target division information.

8. An incident angle gather division device, characterized in that: include: An acquisition module is configured to acquire incident angle gathers of the completed well within a target time window for a target layer; A determination module is configured to determine an amplitude characteristic distribution and a waveform coefficient characteristic distribution of the incident angle gather within the target time window, wherein the waveform coefficient characteristic distribution represents a change in waveform correlation between any two adjacent seismic traces in the incident angle gather within the target time window; A division module is configured to divide the incident angle gathers in the amplitude characteristic dimension according to the amplitude mutation points in the amplitude characteristic distribution, and generate first gather division information including a near-path incident angle range, a middle-path incident angle range, and a far-path incident angle range under the amplitude characteristic dimension according to the amplitude division result, and divide the incident angle gathers in the waveform dimension according to the waveform mutation points in the waveform coefficient characteristic distribution, and generate second gather division information including a near-path incident angle range, a middle-path incident angle range, and a far-path incident angle range under the waveform dimension according to the waveform division result; a generating module, which determines first near-path incident angle information, first middle-path incident angle information and first far-path incident angle information corresponding to the incident angle gather based on the first gather division information, and determines second near-path incident angle information, second middle-path incident angle information and second far-path incident angle information corresponding to the incident angle gather based on the second gather division information; Determine target near-path incident angle information corresponding to the first near-path incident angle information and the second near-path incident angle information, target mid-path incident angle information corresponding to the first mid-path incident angle information and the second mid-path incident angle information, and target far-path incident angle information corresponding to the first far-path incident angle information and the second far-path incident angle information; The target near-path incident angle information, the target mid-path incident angle information and the target far-path incident angle information constitute target division information, wherein the target division information is used for prestack inversion.

9. A computing device, characterized in that include: Memory and processor; The memory is used to store computer executable instructions, and the processor is used to execute the computer executable instructions. When the computer executable instructions are executed by the processor, the steps of the incident angle track set division method described in any one of claims 1 to 7 are implemented.

10. A computer-readable storage medium, characterized in that: It stores computer executable instructions, which, when executed by a processor, can implement the steps of the incident angle track gather division method described in any one of claims 1 to 7.

11. A computer program product, characterized in that The method comprises a computer program or an instruction, which, when executed by a processor, implements the steps of the incident angle gather division method as claimed in any one of claims 1 to 7.

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