A method and apparatus for automatically identifying stratigraphic unconformities from seismic data

Abstract

The application discloses a method and device for automatically identifying a stratigraphic unconformity surface from seismic data, and the method comprises the following steps: performing seismic stratigraphic body analysis on seismic data of a study area to determine a first age stratigraphic body; performing spatial interpolation processing on the first age stratigraphic body to obtain a second age stratigraphic body; determining a relative stratigraphic thickness body, a relative stratigraphic amplitude difference body and a relative stratigraphic dip angle body according to the second age stratigraphic body; determining a stratigraphic unconformity feature body according to the relative stratigraphic thickness body, the relative stratigraphic amplitude difference body and the relative stratigraphic dip angle body; and determining a stratigraphic unconformity surface according to the stratigraphic unconformity feature body.

Description

Technical Field

[0001] This article relates to the fields of seismic signal processing and geological integrated research technology, and in particular to a method and apparatus for automatically identifying stratigraphic unconformities from seismic data. Background Technology

[0002] According to relevant statistics and estimates, 70-75% of the total reserves of economically significant mineral resources on Earth are of sedimentary or sedimentary-metamorphic origin. Sedimentary rock strata are rich areas for various solid, fluid, or gaseous mineral resources. In addition to well-known energy minerals such as oil, natural gas, coal, and uranium, sedimentary strata also contain various salt minerals and sedimentary metallic minerals. Among them, the vast majority of aluminum and phosphate deposits, and most manganese and iron deposits are found in or related to sedimentary rocks. Furthermore, gold, tungsten, tin, diamonds, and various rare element minerals are often found in the form of placer deposits in sand and gravel. Therefore, conducting exploration of sedimentary rock strata is of great significance to human economic and social development.

[0003] According to sedimentary petrology and geological theories, sedimentary rocks are typically distributed in layers due to the influence of hydrodynamics and gravity, and are commonly referred to as "strata." A stratum is the collective term for all layered rocks on the Earth's surface or within the lithosphere; it is a single layer or group of rock strata with consistent or similar lithological and physical properties, clearly distinguishable from the layers above and below. The main types of strata include volcanic strata, metamorphic strata, and sedimentary strata. Strata can be separated by obvious bedding planes or sedimentary discontinuities, or by less distinct boundaries such as lithology, fossils, mineral or chemical composition, or physical properties.

[0004] Sedimentary strata are characterized by stratification and rhythm. In normal sedimentary environments (i.e., without stratigraphic inversion), earlier-formed strata lie beneath, and later-formed strata lie above. The interfaces between layers can be distinct bedding planes or sedimentary hiatuses, or unconformities formed by weathering, water erosion, and other processes. An unconformity is a stratigraphic boundary where, after regional uplift of a former sedimentary area, sedimentary hiatus and erosion occurred, followed by subsequent subsidence and re-deposition, resulting in gaps, pinch-outs, or abrupt changes in thickness in certain parts of adjacent strata. Unconformities indicate certain or drastic changes in the sedimentary characteristics between adjacent strata, separating two sets of strata—older and newer—with a certain geological age gap, and always lacking strata of certain geological ages between the upper and lower sets. In strata near unconformities (usually the underlying strata), geological phenomena such as rock weathering, pores, cavities, and fissures are well-developed. Furthermore, since the strata above and below the unconformity were deposited in different geological periods, the lithology, mineral composition, and various physical properties of the strata are significantly different, resulting in obvious differences in seismic response.

[0005] In oil and gas exploration, stratigraphic unconformities are an important tectonic phenomenon and mineralization indicator. Metallogenic belts typically develop near unconformities, serving as favorable pathways and reservoirs for mineral resources such as oil and gas, and playing a crucial indicative role in oil and gas exploration. Therefore, the identification of stratigraphic unconformities is one of the key steps in comprehensive geological research, especially in sequence stratigraphic interpretation.

[0006] In some technologies, the identification of stratigraphic unconformities mainly relies on seismic data and is primarily achieved through manual visual identification, which is not only inefficient but also lacks objectivity. Since seismic data contains valuable information reflecting stratigraphic unconformities, and seismic exploration is currently the most important method for oil and gas exploration, it is an urgent problem to be solved to develop a method that automatically identifies and extracts stratigraphic unconformities from seismic data using only seismic information. Summary of the Invention

[0007] This application provides a method and apparatus for automatically identifying stratigraphic unconformities from seismic data. The method can determine the relative stratigraphic thickness volume, the relative stratigraphic amplitude difference volume, and the relative stratigraphic dip volume based on seismic data, and then automatically identify stratigraphic unconformities, thereby improving the efficiency, accuracy, and objectivity of seismic data interpretation, sequence stratigraphy interpretation, and comprehensive geological research.

[0008] In a first aspect, this application provides a method for automatically identifying stratigraphic unconformities from seismic data, the method comprising:

[0009] Seismic stratigraphic analysis was performed on the seismic data of the study area to determine the first chronostratigraphic body.

[0010] Spatial interpolation is performed on the first chronostratigraphic body to obtain the second chronostratigraphic body;

[0011] Based on the second chronostratigraphic body, determine the relative stratigraphic thickness body, the relative stratigraphic amplitude difference body, and the relative stratigraphic dip body respectively;

[0012] The unconformity feature body is determined based on the relative stratigraphic thickness volume, the relative stratigraphic amplitude difference volume, and the relative stratigraphic dip volume;

[0013] The stratigraphic unconformity surface is determined based on the stratigraphic unconformity features.

[0014] In one exemplary embodiment, the step of performing seismic stratigraphic analysis on seismic data of the study area to determine the first chronostratigraphic body includes:

[0015] Seismic stratigraphic analysis was used to determine multiple stratigraphic levels from the seismic data of the study area.

[0016] The identified strata are combined according to the order of stratigraphic deposition to form the first chronostratigraphic body.

[0017] In one exemplary embodiment, the step of spatially interpolating the first chronostratigraphic body to obtain the second chronostratigraphic body includes:

[0018] The data of each stratum in the first chronostratigraphic body are spatially interpolated using a time interpolation method to form the second chronostratigraphic body.

[0019] In one exemplary embodiment, determining the relative stratigraphic thickness body based on the second chronostratigraphic body includes:

[0020] Each stratum in the second chronostratigraphic body is taken as the first stratum according to the order of strata from top to bottom, and a stratum pair is formed based on the first stratum and the next stratum adjacent to the first stratum.

[0021] If the first layer forms a layer pair, the following operations are performed: the next layer adjacent to the first layer is taken as the second layer; a time difference matrix is ​​determined based on the time of each layer point of the first layer and the time of the corresponding layer point of the second layer; each element in the time difference matrix is ​​normalized; and the normalized time difference matrix is ​​used as the relative stratigraphic thickness matrix of the first layer.

[0022] If the first stratum cannot form a stratum pair, then the relative stratigraphic thickness matrix of the previous stratum of the first stratum is used as the relative stratigraphic thickness matrix of the first stratum.

[0023] The determined relative stratigraphic thickness matrix is ​​combined according to the stratigraphic depositional sequence to obtain the relative stratigraphic thickness volume.

[0024] In one exemplary embodiment, determining the relative stratigraphic amplitude difference body based on the second chronostratigraphic body includes:

[0025] Each stratum in the second chronostratigraphic body is designated as the first stratum in descending order of stratigraphy; stratigraphic pairs are formed based on the first stratum and the next adjacent stratum.

[0026] If the first layer forms a layer pair, the following operations are performed: the next layer adjacent to the first layer is taken as the second layer; the absolute value of the seismic amplitude difference is determined based on the seismic amplitude of each point in the first layer and the seismic amplitude of each point in the second layer, and an amplitude difference matrix is ​​established; each element in the amplitude difference matrix is ​​normalized; the normalized amplitude difference matrix is ​​used as the relative stratigraphic amplitude difference matrix of the first layer.

[0027] If the first layer cannot form a layer pair, then the relative stratigraphic amplitude difference matrix of the layer preceding the first layer is used as the relative stratigraphic amplitude difference matrix of the first layer.

[0028] The relative stratigraphic amplitude matrices of all strata are combined according to the stratigraphic depositional order to obtain the relative stratigraphic amplitude difference.

[0029] In one exemplary embodiment, determining the relative stratigraphic dip body based on the second chronostratigraphic body includes:

[0030] Each stratum in the second chronostratigraphic body is designated as the first stratum, arranged from top to bottom.

[0031] Calculate the dip angle of each stratum point in the first stratum relative to the stratigraphic dip angle, and establish the stratigraphic dip angle matrix of the first stratum based on the dip angles of all stratum points.

[0032] The dip matrix of all strata is combined according to the stratigraphic depositional order to obtain a sequence of stratigraphic dip matrices;

[0033] Vertical nonlinear interpolation and normalization are performed on the stratigraphic dip matrix sequence to obtain the relative stratigraphic dip volume.

[0034] In one exemplary embodiment, calculating the dip angle of each stratum point in the first stratum relative to the formation includes:

[0035] In the first layer, one layer site is taken out in sequence as the first layer site, and the layer site adjacent to the first layer site is selected to form a layer site pair;

[0036] If the first layer site forms a layer site pair, then the following operation is performed:

[0037] The layer sites adjacent to the first layer sites are designated as the second layer sites;

[0038] Calculate the time difference between the second layer site and the first layer site;

[0039] The calculated time difference is used as the relative dip angle of the first layer site;

[0040] If the first layer site cannot form a layer site pair, then the opposite of the relative stratigraphic dip angle of the left adjacent layer site of the first layer site is taken as the relative stratigraphic dip angle of the first layer site.

[0041] In one exemplary embodiment, the step of performing vertical nonlinear interpolation and normalization on the formation dip matrix sequence to obtain a relative formation dip volume includes:

[0042] Obtain the relative dip angle of different strata corresponding to the same coordinate point in the stratigraphic dip angle matrix sequence;

[0043] Nonlinear interpolation is performed on the relative stratigraphic dip angles of different stratigraphic positions corresponding to the same coordinate point to obtain a vertically equally spaced sequence of relative stratigraphic dip angles.

[0044] The relative stratigraphic dip angle sequence arranged vertically at equal intervals is normalized to obtain the relative stratigraphic dip angle body.

[0045] In one exemplary embodiment, determining the formation unconformity feature body based on the relative formation thickness volume, the relative formation amplitude difference volume, and the relative formation dip volume includes:

[0046] The relative stratigraphic thickness volume, the relative stratigraphic amplitude difference volume, and the relative stratigraphic dip volume are weighted and averaged to form a stratigraphic unconformity feature volume.

[0047] In one exemplary embodiment, determining the stratigraphic unconformity surface based on the stratigraphic unconformity feature body includes:

[0048] The first derivative of the unconformity feature of the strata is calculated to obtain a sequence of first derivatives.

[0049] The first derivative sequence is normalized to obtain the stratigraphic unconformity index sequence;

[0050] The unconformity surface is determined based on the stratigraphic unconformity index sequence and a preset threshold.

[0051] In one exemplary embodiment, determining the unconformity surface based on the stratigraphic unconformity index sequence and a preset threshold includes:

[0052] If the unconformity index is greater than or equal to a preset threshold, the stratum corresponding to the unconformity index is the unconformity surface.

[0053] If the unconformity index of the strata is less than a preset threshold, the stratum is a stratum conformity surface.

[0054] In a second aspect, embodiments of the present invention provide an apparatus for automatically identifying stratigraphic unconformities from seismic data, comprising a first chronostratigraphic body analysis module, a second chronostratigraphic body analysis module, a stratigraphic unconformity attribute body calculation module, a stratigraphic unconformity feature body calculation module, and a stratigraphic unconformity surface calculation module;

[0055] The first-generation stratigraphic analysis module is used to perform seismic stratigraphic analysis on the seismic data of the study area to determine the first-generation stratigraphic body;

[0056] The second chronostratigraphic body analysis module is used to perform spatial interpolation on the first chronostratigraphic body to obtain the second chronostratigraphic body.

[0057] The stratigraphic unconformity attribute volume calculation module is used to determine the relative stratigraphic thickness volume, the relative stratigraphic amplitude difference volume, and the relative stratigraphic dip volume based on the second chronostratigraphic volume.

[0058] The unconformity feature calculation module is used to determine the unconformity feature based on the relative stratigraphic thickness volume, the relative stratigraphic amplitude difference volume, and the relative stratigraphic dip volume;

[0059] The stratigraphic unconformity surface calculation module is used to determine the stratigraphic unconformity surface based on the stratigraphic unconformity feature body.

[0060] In one exemplary embodiment, the formation unconformity property volume calculation module includes a relative formation thickness volume calculation unit, a relative formation amplitude difference volume calculation unit, and a relative formation dip angle volume calculation unit;

[0061] The relative stratigraphic thickness calculation unit is used to determine the relative stratigraphic dip volume based on the second chronostratigraphic volume.

[0062] The relative stratigraphic amplitude difference calculation unit is used to determine the relative stratigraphic amplitude difference volume based on the second chronostratigraphic volume;

[0063] The relative stratigraphic dip calculation unit is used to determine the relative stratigraphic dip based on the second geostratigraphic body.

[0064] Thirdly, embodiments of the present invention provide a computer program product capable of automatically identifying stratigraphic unconformities from seismic data, comprising a computer program / instruction that, when executed by a processor, implements the method for automatically identifying stratigraphic unconformities from seismic data as described in any of the above embodiments.

[0065] Compared with related technologies, this application provides a method and apparatus for automatically identifying stratigraphic unconformities from seismic data. The method includes: performing seismic stratigraphic analysis on seismic data of the study area to determine a first-generation stratigraphic body; performing spatial interpolation on the first-generation stratigraphic body to obtain a second-generation stratigraphic body; determining a relative stratigraphic thickness body, a relative stratigraphic amplitude difference body, and a relative stratigraphic dip body based on the second-generation stratigraphic body; determining a stratigraphic unconformity feature body based on the relative stratigraphic thickness body, the relative stratigraphic amplitude difference body, and the relative stratigraphic dip body; and determining a stratigraphic unconformity surface based on the stratigraphic unconformity feature body. This application determines the relative stratigraphic thickness body, the relative stratigraphic amplitude difference body, and the relative stratigraphic dip body based on seismic data, and further automatically identifies stratigraphic unconformities based on the determined relative stratigraphic thickness body, relative stratigraphic amplitude difference body, and relative stratigraphic dip body, thereby improving the efficiency, accuracy, and objectivity of sequence stratigraphic interpretation.

[0066] Other features and advantages of this application will be set forth in the following description, and will be apparent in part from the description, or may be learned by practicing the application. Other advantages of this application can be realized and obtained by means of the solutions described in the description and the accompanying drawings. Attached Figure Description

[0067] The accompanying drawings are used to provide an understanding of the technical solutions of this application and constitute a part of the specification. They are used together with the embodiments of this application to explain the technical solutions of this application and do not constitute a limitation on the technical solutions of this application.

[0068] Figure 1 This is a flowchart illustrating a method for automatically identifying stratigraphic unconformities from seismic data according to an embodiment of this application.

[0069] Figure 2 This is a flowchart illustrating the determination of relative stratigraphic thickness based on a second-generation stratigraphic body in some exemplary embodiments;

[0070] Figure 3 This is a flowchart illustrating the determination of relative stratigraphic amplitude differences based on second-generation stratigraphic bodies in some exemplary embodiments;

[0071] Figure 4 This is a flowchart illustrating the determination of relative stratigraphic dip based on a second-generation stratigraphic body in some exemplary embodiments;

[0072] Figure 5 These are schematic diagrams of stratigraphic points in some exemplary embodiments;

[0073] Figure 6 These are schematic diagrams showing the locations of the first and second stratigraphic points in some exemplary embodiments;

[0074] Figure 7This is a schematic diagram of a device for automatically identifying stratigraphic unconformities from seismic data according to an embodiment of this application;

[0075] Figure 8 This is a schematic diagram of an attribute volume calculation module in some exemplary embodiments;

[0076] Figure 9 These are schematic diagrams of seismic profiles in some exemplary embodiments;

[0077] Figure 10 These are first-generation stratigraphic bodies extracted from seismic data in some exemplary embodiments;

[0078] Figure 11 These are stratigraphic dip profiles extracted from seismic data based on chronostratigraphic bodies in some exemplary embodiments;

[0079] Figure 12 This is a schematic diagram of the stratigraphic unconformity index as defined in some exemplary embodiments;

[0080] Figure 13 These are schematic diagrams of stratigraphic unconformities identified in some exemplary embodiments. Detailed Implementation

[0081] This application describes several embodiments, but these descriptions are exemplary and not restrictive, and it will be apparent to those skilled in the art that many more embodiments and implementations are possible within the scope of the embodiments described herein. Although many possible combinations of features are shown in the drawings and discussed in the detailed description, many other combinations of the disclosed features are also possible. Unless specifically limited, any feature or element of any embodiment may be used in combination with, or may replace, any feature or element of any other embodiment.

[0082] This application includes and contemplates combinations of features and elements known to those skilled in the art. The embodiments, features, and elements disclosed in this application may also be combined with any conventional features or elements to form a unique inventive scheme as defined by the claims. Any feature or element of any embodiment may also be combined with features or elements from other inventive schemes to form another unique inventive scheme as defined by the claims. Therefore, it should be understood that any feature shown and / or discussed in this application may be implemented individually or in any suitable combination. Therefore, the embodiments are not limited except by the limitations imposed by the appended claims and their equivalents. Furthermore, various modifications and changes may be made within the scope of the appended claims.

[0083] Furthermore, in describing representative embodiments, the specification may have presented methods and / or processes as a specific sequence of steps. However, the method or process should not be limited to the specific order of steps described herein, to the extent that it does not depend on such a specific order. As will be understood by those skilled in the art, other sequences of steps are also possible. Therefore, the specific order of steps set forth in the specification should not be construed as a limitation of the claims. Moreover, the claims concerning the method and / or process should not be limited to the steps performed in the written order, and those skilled in the art will readily understand that these orders can be varied and still remain within the spirit and scope of the embodiments of this application.

[0084] Stratigraphic unconformities are usually sequence boundaries in sequence stratigraphy studies. They are indicators of sedimentary sequence boundaries or sedimentary discontinuities, and are the main markers for identifying sequence and systems tracts in sequence stratigraphic interpretation and an important basis for sedimentary cycle analysis. Therefore, they play an important role in stratigraphic sedimentary characteristic studies and sequence stratigraphic analysis.

[0085] Stratigraphic unconformities typically exhibit the following characteristics on seismic profiles:

[0086] (1) The strata above and below the unconformity have characteristics such as termination and pinch-out, which are reflected in the seismic profile as rapid changes in stratum thickness;

[0087] (2) The lithology, mineral composition and various physical properties of the strata above and below the unconformity are significantly different, and they are usually formed by weathering and erosion. On the seismic profile, they are usually characterized by strong reflection and drastic changes in the seismic response intensity (i.e., the amplitude of seismic waves) of adjacent strata.

[0088] (3) The different attitudes (lateral distribution characteristics of strata) of the strata above and below the unconformity surface will result in large or drastic changes in the dip angle of the strata on the seismic profile.

[0089] Based on the above analysis, information such as stratum thickness, seismic reflection intensity (seismic wave amplitude), and stratum dip angle in the seismic response are the main characteristics that distinguish stratigraphic unconformities from other stratigraphic interfaces. Therefore, stratigraphic unconformities can be automatically identified from seismic data based on these characteristics.

[0090] In some techniques, sequence stratigraphy interpretation relies primarily on identifying artificial stratigraphic unconformities and sequence boundaries using seismic data, which is not only inefficient but also lacks objectivity. Based on the problems existing in conventional seismic data interpretation, sequence stratigraphy interpretation, and comprehensive geological studies, the inventors propose a method for automatically identifying and extracting stratigraphic unconformities from seismic data. This method utilizes the information from these unconformities to establish a sequence stratigraphic framework, thereby improving the efficiency of sequence stratigraphy interpretation and comprehensive geological studies.

[0091] This invention provides a method for automatically identifying stratigraphic unconformities from seismic data, such as... Figure 1 As shown, the method includes steps S100-S140, as detailed below:

[0092] Step S100: Perform seismic stratigraphic analysis on the seismic data of the study area to determine the first chronostratigraphic body;

[0093] Step S110: Perform spatial interpolation on the first chronostratigraphic body to obtain the second chronostratigraphic body;

[0094] Step S120: Determine the relative stratigraphic thickness volume, relative stratigraphic amplitude difference volume, and relative stratigraphic dip volume based on the second-generation stratigraphic body;

[0095] Step S130: Determine the unconformity feature body based on the relative stratigraphic thickness volume, the relative stratigraphic amplitude difference volume, and the relative stratigraphic dip volume;

[0096] Step S140: Determine the stratigraphic unconformity surface based on the stratigraphic unconformity feature body.

[0097] In this embodiment, seismic stratigraphic analysis is performed on the seismic data of the study area to form a first chronostratigraphic body. This chronostratigraphic body refers to a sequence of stratigraphic layers automatically extracted from the seismic data using seismic stratigraphic analysis techniques, reflecting the spatial morphology of the stratigraphy, and then systematically combined into a chronostratigraphic body. A chronostratigraphic body consists of one or more layers, which cannot overlap. The order of the layers represents the sequence of sedimentary changes from youngest to oldest; for example, layers from top to bottom indicate sedimentary changes from youngest to oldest, with the uppermost layers being younger and the lowermost layers being older.

[0098] In one exemplary embodiment, seismic stratigraphy analysis is performed on seismic data of the study area to determine a first-generation stratigraphic body. This includes: using seismic stratigraphy analysis technology to determine multiple strata in the seismic data of the study area; and combining the determined multiple strata according to the order of stratigraphic deposition to form a first-generation stratigraphic body. In this embodiment, the seismic stratigraphy analysis technology is an automatic relative geological timescale analysis technology that can automatically extract a set of strata reflecting the relative geological age and sedimentary characteristics of the strata from the seismic data.

[0099] In one exemplary embodiment, spatial interpolation is performed on a first-dimensional stratigraphic body to obtain a second-dimensional stratigraphic body. This includes: spatially interpolating the data of each stratum in the first-dimensional stratigraphic body using a linear interpolation method to form the second-dimensional stratigraphic body. In this embodiment, spatial interpolation of the first-dimensional stratigraphic body refers to the fact that some strata in the first-dimensional stratigraphic body may pinch out at points of drastic changes in stratigraphic thickness, resulting in these strata not covering the entire seismic measurement space. Interpolation is performed on the strata that do not cover the entire seismic measurement space to ensure that all strata have valid values ​​in the seismic space. The interpolation method is not specifically limited; it can be based on the linear ratio between adjacent strata or on the spatial trend surface.

[0100] In one exemplary embodiment, the relative stratigraphic thickness volume is determined based on the second chronostratigraphic body, such as... Figure 2 The flowchart shown illustrates the calculation of relative formation thickness. The implementation process includes:

[0101] Step 200: Following the stratigraphic order from top to bottom (i.e., from newest to oldest geologically), each stratigraphic unit in the second chronological stratigraphic body is designated as the first stratigraphic unit. Stratigraphic pairs are formed based on the first stratigraphic unit and the next adjacent stratigraphic unit (the stratigraphic unit below the first stratigraphic unit). The next adjacent stratigraphic unit is spatially located below the first stratigraphic unit, and geologically older than the first stratigraphic unit, is designated as the second stratigraphic unit. The first and second stratigraphic units are considered as one stratigraphic pair. For example, in the second chronological stratigraphic body, there are five stratigraphic units from top to bottom: H1, H2, H3, H4, and H5. When H1 is selected as the first stratigraphic unit, H1 and H2 form a stratigraphic pair; when H2 is selected as the first stratigraphic unit, H2 and H3 form a stratigraphic pair. These five stratigraphic units will form four stratigraphic pairs: H1-H2, H2-H3, H3-H4, and H4-H5.

[0102] Step 210: If the first layer forms a stratigraphic pair, perform the following operations: Determine the time difference matrix based on the time of each stratigraphic point in the first layer and the time of the corresponding stratigraphic point in the second layer; normalize each element in the time difference matrix; use the normalized time difference matrix as the relative stratigraphic thickness matrix of the first layer; taking the H1-H2 stratigraphic pair as an example, the matrix constructed by the H1 layer and the matrix constructed by the H2 layer are two matrices with the same dimension and size, and the elements in the matrix represent the stratigraphic values ​​of the stratigraphic points. Calculate the time difference between these two stratigraphic matrices (i.e., calculate the time values ​​of the corresponding positions of each element in the H1 and H2 matrices) to form the time difference matrix; take the absolute value of each element in the time difference matrix and normalize it, with the normalized value range being [0.0, 1.0]; use the normalized time difference matrix as the relative stratigraphic thickness matrix of the H1 layer.

[0103] Step 220: If the first stratum cannot form a stratigraphic pair, that is, the first stratum is located at the bottom of the target stratigraphic segment in the study area and there are no other strata below the first stratum, then the relative stratigraphic thickness matrix of the stratum above the first stratum is used as the relative stratigraphic thickness matrix of the first stratum; for example: among the above 5 strata, H5 is the bottommost stratum and no stratum forms a stratigraphic pair with H5, then the relative stratigraphic thickness matrix of the stratum above H5, H4, is used as the relative stratigraphic thickness matrix of H5.

[0104] Repeat steps 200-220. After all layers have been processed, proceed to step 230.

[0105] Step 230: Combine the determined relative stratigraphic thickness matrix according to the order of the old and new stratigraphic deposits to obtain the relative stratigraphic thickness volume.

[0106] In one exemplary embodiment, a relative stratigraphic amplitude difference body is determined based on a second chronostratigraphic body, such as... Figure 3 The flowchart shown illustrates the calculation of the relative formation amplitude difference. The implementation process includes:

[0107] Step 300: Select each stratum in the second-dimensional stratigraphic body as the first stratum according to the order of strata from top to bottom; form stratum pairs based on the first stratum and the next adjacent stratum; for example: in the second-dimensional stratigraphic body, there are 5 strata from top to bottom: H1, H2, H3, H4, and H5; when H1 is selected as the first stratum, H1 and H2 form a stratum pair; when H2 is selected as the first stratum, H2 and H3 form a stratum pair; these 5 strata will form four stratum pairs: H1-H2, H2-H3, H3-H4, and H4-H5.

[0108] Step 310: If the first layer forms a layer pair, perform the following operations: Take the next adjacent layer of the first layer as the second layer; determine the absolute value of the seismic amplitude difference based on the seismic amplitudes of each point in the first layer and the seismic amplitudes of each point in the second layer, and establish an amplitude difference matrix; normalize each element in the amplitude difference matrix; use the normalized amplitude difference matrix as the relative stratigraphic amplitude difference matrix of the first layer. Taking the H1-H2 layer pair as an example, the matrix constructed by the H1 layer and the matrix constructed by the H2 layer are two matrices with the same dimension and size. Within the time range indicated by the same point in H1 and H2, calculate the average seismic amplitude at that point to form an amplitude matrix; take the absolute value of each element in the amplitude matrix and normalize it, with the normalized value range being [0.0, 1.0]; use the normalized time difference matrix as the relative stratigraphic amplitude matrix of the H1 layer.

[0109] Step 320: If the first stratum cannot form a stratum pair, then the relative stratigraphic amplitude difference matrix of the stratum above the first stratum is used as the relative stratigraphic amplitude difference matrix of the first stratum. For example, the target stratigraphic segment in the study area includes 5 strata: H1, H2, H3, H4, and H5. H5 is the lowest stratum. When H5 is used as the first stratum, there is no stratum below it that can form a stratum pair with H5. Therefore, the relative stratigraphic amplitude difference matrix of the stratum above H5, H4, is used as the relative stratigraphic amplitude matrix of H5.

[0110] Repeat steps 300-320 until all layers have been processed; that is, after calculating a relative stratigraphic amplitude difference matrix for each layer H1, H2, H3, H4, and H5, execute operation step 330.

[0111] Step 330: Combine the determined relative stratigraphic amplitude difference matrix according to the order of the old and new stratigraphic deposits to obtain the relative stratigraphic amplitude difference volume.

[0112] In one exemplary embodiment, the relative stratigraphic dip body is determined based on the second chronostratigraphic body, such as... Figure 4 The flowchart shown illustrates the calculation of the relative dip angle of the formation. The implementation process includes:

[0113] Step 400: Select each stratum in the second chronostratigraphic body as the first stratum according to the order of the strata from top to bottom; for example: in the second chronostratigraphic body, there are 5 strata from top to bottom: H1, H2, H3, H4, and H5; when H1 is selected, H1 is selected as the first stratum; when H5 is selected, H5 is selected as the first stratum.

[0114] Step 410: Calculate the relative dip angle of each stratum point in the first stratum, and establish the stratum dip angle matrix of the first stratum based on the relative dip angles of all stratum points; for example... Figure 5 The diagram shows a single-layer site. It is necessary to calculate the relative dip angle of each site in this layer.

[0115] In this step, the dip angle relative to the strata at each point in the first stratum is calculated, including:

[0116] Step 4101: In the first stratum, take out one stratum site in sequence as the first stratum site, and select the stratum site adjacent to the right of the first stratum site to form a stratum site pair; In this embodiment, when calculating the dip angle of each stratum site relative to the stratum in the first stratum, you can choose to select the stratum site adjacent to the right of the stratum site to form a stratum site pair, or you can select the stratum site adjacent to the left of the stratum site to form a stratum site pair, as long as the form is consistent.

[0117] Step 4102: If the first layer site forms a layer site pair, then perform the following operation:

[0118] Step 41021: Use the layer sites adjacent to the first layer sites as the second layer sites;

[0119] Step 41022: Calculate the time difference between the second-layer sites and the first-layer sites;

[0120] like Figure 6 As shown, in this step, the formula for calculating the time difference between the second-layer sites and the first-layer sites is: Δt 2,1 = t2 - t1; t1 is the first-layer locus, t2 is the second-layer locus, Δt 2,1 This represents the time difference between the second-layer site and the first-layer site; for other layers, 1 and 2 in the above formula will change accordingly based on the layer number.

[0121] For each site in each layer, the time difference between that site and its adjacent sites is calculated.

[0122] Step 41023: Use the calculated time difference as the relative dip angle of the first layer site.

[0123] Step 4103: If the first layer site cannot form a layer site pair, then the opposite of the relative stratigraphic dip angle of the left adjacent layer site of the first layer site (i.e., the product of the relative stratigraphic dip angle and -1) is taken as the relative stratigraphic dip angle of the first layer site.

[0124] Step 420: Combine the dip matrices of all stratigraphic positions according to the stratigraphic depositional order to obtain a sequence of stratigraphic dip matrices;

[0125] Step 430: Perform vertical nonlinear interpolation and normalization on the formation dip matrix sequence to obtain the relative formation dip volume.

[0126] In this step, the formation dip matrix sequence is subjected to vertical nonlinear interpolation and normalization to obtain the relative formation dip volume. The process includes:

[0127] Step 4301: Obtain the relative dip angle of different stratigraphic positions corresponding to the same coordinate point in the stratigraphic dip angle matrix sequence;

[0128] Step 4302: Perform nonlinear interpolation on the relative stratigraphic dip angles of different stratigraphic positions corresponding to the same coordinate point to obtain a vertically equally spaced sequence of relative stratigraphic dip angles;

[0129] Step 4303: Normalize the vertically equally spaced relative stratigraphic dip sequence to obtain the relative stratigraphic dip body.

[0130] In step 4301, the relative stratigraphic dip angles with the same layer number but different layer numbers are sequentially extracted from the seismic dip angle matrix of each layer, that is, the relative stratigraphic dip angles of different layers corresponding to the same coordinate point; nonlinear interpolation is performed on the relative stratigraphic dip angles of different layers corresponding to the same coordinate point to form a vertically equally spaced stratigraphic dip angle sequence.

[0131] In one exemplary embodiment, determining the unconformity feature body based on the relative formation thickness volume, the relative formation amplitude difference volume, and the relative formation dip volume includes: using a weighted average method to determine the unconformity feature body for the relative formation thickness volume, the relative formation amplitude difference volume, and the relative formation dip volume. In this embodiment, by default, the weighting coefficients of the three data volumes are equal when performing the weighted average calculation; however, they can also be set to unequal values ​​according to actual conditions, as long as the sum of the weighting coefficients of the three data volumes is 1.0.

[0132] In one exemplary embodiment, determining a stratigraphic unconformity surface based on stratigraphic unconformity features includes:

[0133] Step 1: Perform first-order derivative calculations on the stratigraphic unconformity features to obtain a sequence of first-order derivatives;

[0134] Step 2: Normalize the first derivative sequence to obtain the unconformity index sequence.

[0135] Step 3: Determine the unconformity surface based on the stratigraphic unconformity index sequence and a preset threshold. In this embodiment, extracting the stratigraphic unconformity index sequence from the stratigraphic unconformity feature body refers to performing a first-order derivative operation on the stratigraphic unconformity feature body to obtain the first-order derivative sequence of the seismic unconformity feature body, then normalizing the first-order derivative sequence, and calling the normalized first-order derivative sequence the stratigraphic unconformity index sequence. The stratigraphic unconformity index can indicate the degree of drastic change in the characteristics of adjacent strata. The so-called derivative operation is a well-known calculation method, defined as the limit of the quotient of the increment of the dependent variable and the increment of the independent variable when the increment of the independent variable approaches zero. There are various derivatives, the most commonly used being the first derivative. For the stratigraphic feature body in this embodiment, the physical meaning of its first derivative is that it can reflect the rate of change of stratigraphic characteristics of adjacent strata, that is, the degree of drastic change in stratigraphic characteristics. The larger the first derivative, the more drastic the change in stratigraphic characteristics, and vice versa.

[0136] In one exemplary embodiment, determining the unconformity surface based on the stratigraphic unconformity index sequence and a preset threshold includes:

[0137] If the unconformity index is greater than or equal to a preset threshold, the stratum corresponding to the unconformity index is the unconformity surface.

[0138] If the unconformity index is less than a preset threshold, the stratum is a stratigraphic conformity surface. In this embodiment, the preset threshold is set according to the specific conditions of the region. For example, marking strata with an unconformity index greater than the preset threshold as stratigraphic unconformities surfaces means setting a value between 0.5 and 0.95 as the preset threshold range, reassigning the corresponding unconformity index to 0.0 for strata with an unconformity index less than this preset threshold range, and then marking strata with an unconformity index not equal to 0.0 as stratigraphic unconformities surfaces.

[0139] After identifying the stratigraphic unconformity, the sequence of unconformities is output. This output refers to a software module that outputs the stratigraphic layers marked as unconformities in chronostratigraphic order as computer disk files, computer images, or other forms of data. The output format of the stratigraphic unconformities is a one-dimensional or two-dimensional matrix (array). If the seismic area is two-dimensional, a one-dimensional matrix (array) is output; if the seismic area is three-dimensional, a two-dimensional matrix (array) is output, with each stratigraphic layer corresponding to one matrix (array).

[0140] The beneficial effects of this invention lie in its ability to automatically identify stratigraphic unconformities within a chronostratigraphic domain by utilizing variations in stratigraphic thickness, dip angle, and seismic reflection intensity. It enables unconformity index analysis without human intervention and automatically identifies and extracts potential unconformities from the chronostratigraphic body based on the unconformity index sequence. Because the mathematical analysis methods employed can rapidly identify and extract unconformities, it effectively improves the efficiency, accuracy, and objectivity of sequence stratigraphic interpretation.

[0141] This disclosure also provides an apparatus for automatically identifying stratigraphic unconformities from seismic data, such as... Figure 7 As shown, it includes a first-generation stratigraphic body analysis module 700, a second-generation stratigraphic body analysis module 710, a stratigraphic unconformity attribute body calculation module 720, a stratigraphic unconformity feature body calculation module 730, and a stratigraphic unconformity surface calculation module 740.

[0142] The first chronostratigraphic analysis module 700 is used to perform seismic stratigraphic analysis on the seismic data of the study area to determine the first chronostratigraphic body.

[0143] The second chronostratigraphic body analysis module 710 is used to perform spatial interpolation processing on the first chronostratigraphic body to obtain the second chronostratigraphic body.

[0144] The stratigraphic unconformity attribute volume calculation module 720 is used to determine the relative stratigraphic thickness volume, the relative stratigraphic amplitude difference volume, and the relative stratigraphic dip volume based on the second age stratigraphic volume;

[0145] The stratigraphic unconformity feature calculation module 730 is used to determine the stratigraphic unconformity feature based on the relative stratigraphic thickness volume, the relative stratigraphic amplitude difference volume, and the relative stratigraphic dip volume;

[0146] The stratigraphic unconformity surface calculation module 740 is used to determine the stratigraphic unconformity surface based on the stratigraphic unconformity feature body.

[0147] In one exemplary embodiment, such as Figure 8 As shown, the formation unconformity attribute volume calculation module 720 includes a relative formation thickness volume calculation unit 7201, a relative formation amplitude difference volume calculation unit 7202, and a relative formation dip angle volume calculation unit 7203;

[0148] The relative stratigraphic thickness calculation unit 7201 is used to determine the relative stratigraphic dip volume based on the second geostratigraphic volume;

[0149] The relative stratigraphic amplitude difference calculation unit 7202 is used to determine the relative stratigraphic amplitude difference based on the second geostratigraphic body;

[0150] The relative stratigraphic dip body calculation unit 7203 is used to determine the relative stratigraphic dip body based on the second geostratigraphic body.

[0151] This disclosure also provides a computer program product capable of automatically identifying stratigraphic unconformities from seismic data, comprising a computer program / instructions, characterized in that, when executed by a processor, the computer program / instructions implement the method for automatically identifying stratigraphic unconformities from seismic data as described in any of the above embodiments.

[0152] Example 1

[0153] This example demonstrates a method for automatically identifying stratigraphic unconformities from seismic data, as follows:

[0154] Step 1: Perform seismic stratigraphic analysis on the seismic data to form the first chronostratigraphic body; such as... Figure 9 The diagram shows a seismic profile, with black lines representing the top and bottom boundaries of the target layer. Seismic stratigraphic analysis of this seismic data yielded a first-order chronostratigraphic body, as shown below. Figure 10 As shown.

[0155] Step 2: Spatial interpolation of the first chronostratigraphic body to form the second chronostratigraphic body;

[0156] In this step, the data of each stratum in the first chronostratigraphic body are spatially interpolated using linear interpolation to form the second chronostratigraphic body.

[0157] Step 3: Calculate the relative stratigraphic thickness based on the second-generation stratigraphic body; the process of calculating the relative stratigraphic thickness based on the second-generation stratigraphic body is as follows: Figure 2 As shown, the process is as follows:

[0158] Each stratum in the second chronostratigraphic body is taken as the first stratum according to the order of strata from top to bottom, and a stratum pair is formed based on the first stratum and the next stratum adjacent to the first stratum.

[0159] If the first layer forms a layer pair, the following operations are performed: the next layer adjacent to the first layer is taken as the second layer; a time difference matrix is ​​determined based on the time of each layer point of the first layer and the time of the corresponding layer point of the second layer; each element in the time difference matrix is ​​normalized; and the normalized time difference matrix is ​​used as the relative stratigraphic thickness matrix of the first layer.

[0160] If the first stratum cannot form a stratum pair, then the relative stratigraphic thickness matrix of the previous stratum of the first stratum is used as the relative stratigraphic thickness matrix of the first stratum.

[0161] The determined relative stratigraphic thickness matrix is ​​combined according to the stratigraphic depositional sequence to obtain the relative stratigraphic thickness volume.

[0162] Step 4: Extract the relative stratigraphic amplitude difference volume from the seismic data volume based on the second-generation stratigraphic volume; the process of extracting the relative stratigraphic amplitude difference volume from the seismic data volume based on the second-generation stratigraphic volume is as follows: Figure 3 As shown, the process is as follows:

[0163] Each stratum in the second chronostratigraphic body is designated as the first stratum in descending order of stratigraphy; stratigraphic pairs are formed based on the first stratum and the next adjacent stratum.

[0164] If the first layer forms a layer pair, the following operations are performed: the next layer adjacent to the first layer is taken as the second layer; the absolute value of the seismic amplitude difference is determined based on the seismic amplitude of each point in the first layer and the seismic amplitude of each point in the second layer, and an amplitude difference matrix is ​​established; each element in the amplitude difference matrix is ​​normalized; the normalized amplitude difference matrix is ​​used as the relative stratigraphic amplitude difference matrix of the first layer.

[0165] If the first layer cannot form a layer pair, then the relative stratigraphic amplitude difference matrix of the layer preceding the first layer is used as the relative stratigraphic amplitude difference matrix of the first layer.

[0166] The relative stratigraphic amplitude matrices of all strata are combined according to the stratigraphic depositional order to obtain the relative stratigraphic amplitude difference.

[0167] Step 5: Estimate the relative dip of the stratigraphic body from the seismic data based on the second-generation stratigraphic body; the process of estimating the relative dip of the stratigraphic body from the seismic data based on the second-generation stratigraphic body is as follows: Figure 4 As shown, the process is as follows:

[0168] Each stratum in the second chronostratigraphic body is designated as the first stratum, arranged from top to bottom.

[0169] Calculate the dip angle of each stratum point in the first stratum relative to the stratigraphic dip angle, and establish the stratigraphic dip angle matrix of the first stratum based on the dip angles of all stratum points.

[0170] The dip matrix of all strata is combined according to the stratigraphic depositional order to obtain a sequence of stratigraphic dip matrices;

[0171] Vertical nonlinear interpolation and normalization are performed on the stratigraphic dip matrix sequence to obtain the relative stratigraphic dip volume.

[0172] The calculation of the dip angle relative to the strata at each stratum point in the first stratum includes:

[0173] In the first layer, one layer site is taken out in sequence as the first layer site, and the layer site adjacent to the first layer site is selected to form a layer site pair;

[0174] If the first layer site forms a layer site pair, then the following operation is performed:

[0175] The layer sites adjacent to the first layer sites are designated as the second layer sites;

[0176] Calculate the time difference between the second layer site and the first layer site;

[0177] The calculated time difference is used as the relative dip angle of the first layer site;

[0178] If the first layer site cannot form a layer-site pair, then the opposite of the relative stratigraphic dip angle of the left adjacent layer site of the first layer site (i.e., the product of the relative stratigraphic dip angle and -1) is taken as the relative stratigraphic dip angle of the first layer site.

[0179] In this step, such as Figure 11 The image shown is a stratigraphic dip attribute map extracted from seismic data based on the second-generation stratigraphic body.

[0180] Step 6: Proportional fusion of the relative stratigraphic thickness volume, the relative stratigraphic amplitude difference volume, and the relative stratigraphic dip volume to form a stratigraphic unconformity feature volume;

[0181] Step 7: Determine the stratigraphic unconformity index sequence based on stratigraphic unconformity feature bodies; such as... Figure 12 The figure shown is a stratigraphic unconformity index map of a study area.

[0182] Step 8: Set a threshold value, and mark strata with an unconformity index greater than the threshold value as unconformity surfaces; for example... Figure 13 The image shown is a schematic diagram of the identified stratigraphic unconformity profile.

[0183] Step 9: Output the sequence of unconformities in the formation.

[0184] This example provides a method and apparatus for automatically identifying stratigraphic unconformities from seismic data. It automatically identifies unconformities in the chronostratigraphic domain by utilizing variations in stratigraphic thickness, dip angle, and seismic reflection intensity. Unconformity index analysis is performed without human intervention, and potential unconformities are automatically identified and extracted from the chronostratigraphic body based on the unconformity index sequence. Because the mathematical analysis methods employed can rapidly identify and extract unconformities, the efficiency, accuracy, and objectivity of sequence stratigraphic interpretation can be effectively improved.

[0185] It will be understood by those skilled in the art that all or some of the steps, systems, or apparatuses disclosed above, and their functional modules / units, can be implemented as software, firmware, hardware, or suitable combinations thereof. In hardware implementations, the division between functional modules / units mentioned above does not necessarily correspond to the division of physical components; for example, a physical component may have multiple functions, or a function or step may be performed collaboratively by several physical components. Some or all components may be implemented as software executed by a processor, such as a digital signal processor or microprocessor, or as hardware, or as an integrated circuit, such as an application-specific integrated circuit (ASIC). Such software may be distributed on a computer-readable medium, which may include computer storage media (or non-transitory media) and communication media (or transient media). As is known to those skilled in the art, the term computer storage media includes volatile and non-volatile, removable and non-removable media implemented in any method or technology for storing information (such as computer-readable instructions, data structures, program modules, or other data). Computer storage media include, but are not limited to, RAM, ROM, EEPROM, flash memory or other memory technologies, CD-ROM, digital versatile disc (DVD) or other optical disc storage, magnetic cartridges, magnetic tape, disk storage or other magnetic storage devices, or any other medium that can be used to store desired information and can be accessed by a computer. Furthermore, it is well known to those skilled in the art that communication media typically contain computer-readable instructions, data structures, program modules, or other data in modulated data signals such as carrier waves or other transmission mechanisms, and may include any information delivery medium.

Claims

1. A method for automatically identifying stratigraphic unconformities from seismic data, characterized in that, The method includes: Seismic stratigraphic analysis was performed on the seismic data of the study area to determine the first chronostratigraphic body. Spatial interpolation is performed on the first chronostratigraphic body to obtain the second chronostratigraphic body; Based on the second chronostratigraphic body, determine the relative stratigraphic thickness body, the relative stratigraphic amplitude difference body, and the relative stratigraphic dip body respectively; The unconformity feature body is determined based on the relative stratigraphic thickness volume, the relative stratigraphic amplitude difference volume, and the relative stratigraphic dip volume; Determine the stratigraphic unconformity surface based on the aforementioned stratigraphic unconformity features; The determination of the relative stratigraphic thickness volume, relative stratigraphic amplitude difference volume, and relative stratigraphic dip volume based on the second chronostratigraphic body includes: Establish the relative stratigraphic thickness matrix, relative stratigraphic amplitude difference matrix, and stratigraphic dip matrix of the stratigraphic position based on the stratigraphic position in the second-generation stratigraphic body; The relative stratigraphic thickness volume, relative stratigraphic amplitude difference volume, and relative stratigraphic dip volume are obtained respectively based on the relative stratigraphic thickness matrix, the relative stratigraphic amplitude difference matrix, and the stratigraphic dip angle matrix.

2. The method for automatically identifying stratigraphic unconformities from seismic data according to claim 1, characterized in that, The seismic stratigraphic analysis of the seismic data in the study area to determine the first-generation stratigraphic body includes: Seismic stratigraphic analysis was used to determine multiple stratigraphic levels from the seismic data of the study area. The identified strata are combined according to the order of stratigraphic deposition to form the first chronostratigraphic body.

3. The method for automatically identifying stratigraphic unconformities from seismic data according to claim 2, characterized in that, The step of spatial interpolating the first chronostratigraphic body to obtain the second chronostratigraphic body includes: The data of each stratum in the first chronostratigraphic body are spatially interpolated using linear interpolation to form the second chronostratigraphic body.

4. The method for automatically identifying stratigraphic unconformities from seismic data according to claim 2, characterized in that, Determining the relative stratigraphic thickness based on the second chronostratigraphic body includes: Each stratum in the second chronostratigraphic body is taken as the first stratum according to the order of strata from top to bottom, and a stratum pair is formed based on the first stratum and the next stratum adjacent to the first stratum. If the first layer forms a layer pair, the following operations are performed: the next layer adjacent to the first layer is taken as the second layer; a time difference matrix is ​​determined based on the time of each layer point of the first layer and the time of the corresponding layer point of the second layer; each element in the time difference matrix is ​​normalized; and the normalized time difference matrix is ​​used as the relative stratigraphic thickness matrix of the first layer. If the first stratum cannot form a stratum pair, then the relative stratigraphic thickness matrix of the previous stratum of the first stratum is used as the relative stratigraphic thickness matrix of the first stratum. The determined relative stratigraphic thickness matrix is ​​combined according to the stratigraphic depositional sequence to obtain the relative stratigraphic thickness volume.

5. The method for automatically identifying stratigraphic unconformities from seismic data according to claim 2, characterized in that, Determining the relative stratigraphic amplitude difference body based on the second chronostratigraphic body includes: Each stratum in the second chronostratigraphic body is designated as the first stratum in descending order of stratigraphy; stratigraphic pairs are formed based on the first stratum and the next adjacent stratum. If the first layer forms a layer pair, the following operations are performed: the next layer adjacent to the first layer is taken as the second layer; the absolute value of the seismic amplitude difference is determined based on the seismic amplitude of each point in the first layer and the seismic amplitude of each point in the second layer, and an amplitude difference matrix is ​​established; each element in the amplitude difference matrix is ​​normalized; the normalized amplitude difference matrix is ​​used as the relative stratigraphic amplitude difference matrix of the first layer. If the first layer cannot form a layer pair, then the relative stratigraphic amplitude difference matrix of the layer preceding the first layer is used as the relative stratigraphic amplitude difference matrix of the first layer. The relative stratigraphic amplitude difference matrix of all strata is combined according to the stratigraphic depositional order to obtain the relative stratigraphic amplitude difference volume.

6. The method for automatically identifying stratigraphic unconformities from seismic data according to claim 2, characterized in that, Determining the relative stratigraphic dip body based on the second chronostratigraphic body includes: Each stratum in the second chronostratigraphic body is designated as the first stratum, arranged from top to bottom. Calculate the dip angle of each stratum point in the first stratum relative to the stratigraphic dip angle, and establish the stratigraphic dip angle matrix of the first stratum based on the dip angles of all stratum points. The dip matrix of all strata is combined according to the stratigraphic depositional order to obtain a sequence of stratigraphic dip matrices; Vertical nonlinear interpolation and normalization are performed on the stratigraphic dip matrix sequence to obtain the relative stratigraphic dip volume.

7. The method for automatically identifying stratigraphic unconformities from seismic data according to claim 6, characterized in that, Calculating the relative dip angle of each stratum point in the first stratum includes: In the first layer, one layer site is taken out in sequence as the first layer site, and the layer site adjacent to the first layer site is selected to form a layer site pair; If the first layer site forms a layer site pair, then the following operation is performed: The layer sites adjacent to the first layer sites are designated as the second layer sites; Calculate the time difference between the second layer site and the first layer site; The calculated time difference is used as the relative dip angle of the first layer site; If the first layer site cannot form a layer site pair, then the opposite of the relative stratigraphic dip angle of the left adjacent layer site of the first layer site is taken as the relative stratigraphic dip angle of the first layer site.

8. The method for automatically identifying stratigraphic unconformities from seismic data according to claim 6, characterized in that, The process of performing vertical nonlinear interpolation and normalization on the stratigraphic dip matrix sequence to obtain the relative stratigraphic dip volume includes: Obtain the relative dip angle of different strata corresponding to the same coordinate point in the stratigraphic dip angle matrix sequence; Nonlinear interpolation is performed on the relative stratigraphic dip angles of different stratigraphic positions corresponding to the same coordinate point to obtain a vertically equally spaced sequence of relative stratigraphic dip angles. The relative stratigraphic dip angle sequence arranged vertically at equal intervals is normalized to obtain the relative stratigraphic dip angle body.

9. The method for automatically identifying stratigraphic unconformities from seismic data according to claim 1, characterized in that, The determination of the stratigraphic unconformity feature body based on the relative stratigraphic thickness volume, the relative stratigraphic amplitude difference volume, and the relative stratigraphic dip volume includes: The relative stratigraphic thickness volume, the relative stratigraphic amplitude difference volume, and the relative stratigraphic dip volume are weighted and averaged to form a stratigraphic unconformity feature volume.

10. The method for automatically identifying stratigraphic unconformities from seismic data according to claim 1, characterized in that, The step of determining the stratigraphic unconformity surface based on the stratigraphic unconformity feature body includes: The first derivative of the unconformity feature of the strata is calculated to obtain a sequence of first derivatives. The first derivative sequence is normalized to obtain the unconformity index sequence. The unconformity surface is determined based on the stratigraphic unconformity index sequence and a preset threshold.

11. The method for automatically identifying stratigraphic unconformities from seismic data according to claim 10, characterized in that, The step of determining the unconformity surface based on the stratigraphic unconformity index sequence and a preset threshold includes: If the unconformity index is greater than or equal to a preset threshold, the stratum corresponding to the unconformity index is the unconformity surface. If the unconformity index of the strata is less than a preset threshold, the stratum is a stratum conformity surface.

12. A device for automatically identifying stratigraphic unconformities from seismic data, characterized in that, It includes modules for analyzing first-generation stratigraphic bodies, analyzing second-generation stratigraphic bodies, calculating stratigraphic unconformity attribute bodies, calculating stratigraphic unconformity feature bodies, and calculating stratigraphic unconformity surfaces; The first-generation stratigraphic analysis module is used to perform seismic stratigraphic analysis on the seismic data of the study area to determine the first-generation stratigraphic body; The second chronostratigraphic body analysis module is used to perform spatial interpolation on the first chronostratigraphic body to obtain the second chronostratigraphic body. The stratigraphic unconformity attribute volume calculation module is used to determine the relative stratigraphic thickness volume, the relative stratigraphic amplitude difference volume, and the relative stratigraphic dip volume based on the second chronostratigraphic volume. The unconformity feature calculation module is used to determine the unconformity feature based on the relative stratigraphic thickness volume, the relative stratigraphic amplitude difference volume, and the relative stratigraphic dip volume; The stratigraphic unconformity surface calculation module is used to determine the stratigraphic unconformity surface based on the stratigraphic unconformity feature body. The step of determining the relative stratigraphic thickness volume, the relative stratigraphic amplitude difference volume, and the relative stratigraphic dip volume based on the second chronostratigraphic body includes: Establish the relative stratigraphic thickness matrix, relative stratigraphic amplitude difference matrix, and stratigraphic dip matrix of the stratigraphic position based on the stratigraphic position in the second-generation stratigraphic body; The relative stratigraphic thickness volume, relative stratigraphic amplitude difference volume, and relative stratigraphic dip volume are obtained respectively based on the relative stratigraphic thickness matrix, the relative stratigraphic amplitude difference matrix, and the stratigraphic dip angle matrix.

13. The apparatus for automatically identifying stratigraphic unconformities from seismic data according to claim 12, characterized in that, The formation unconformity attribute volume calculation module includes a relative formation thickness volume calculation unit, a relative formation amplitude difference volume calculation unit, and a relative formation dip angle volume calculation unit; The relative stratigraphic thickness calculation unit is used to determine the relative stratigraphic thickness based on the second chronostratigraphic body; The relative stratigraphic amplitude difference calculation unit is used to determine the relative stratigraphic amplitude difference volume based on the second chronostratigraphic volume; The relative stratigraphic dip calculation unit is used to determine the relative stratigraphic dip based on the second geostratigraphic body.

14. A computer program product capable of automatically identifying stratigraphic unconformities from seismic data, comprising a computer program / instructions, characterized in that, When executed by a processor, the computer program / instruction implements the method for automatically identifying stratigraphic unconformities from seismic data as described in any one of claims 1 to 11.

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