Rapid evaluation method, device, medium and equipment for determining sand-rich area of deepwater fan at edge of land frame

Abstract

The invention relates to a rapid evaluation method and device for determining a land frame edge deepwater fan sand-rich area, a medium and equipment. The method comprises the following steps: S1, selecting a typical seismic reflection profile of a land frame edge along the object source direction; s2, establishing a land frame marginal area sequence stratigraphic framework; s3, identifying a series of land frame slope break points on the seismic sequence interfaces in the step S2 and between the seismic sequence interfaces; s4, recording a time value T of a land frame slope break point; s5, calculating a vertical addition time thickness difference value H; s6, judging the migration type of the land frame edge slope break track; s7, a series of isochronous stratum slices from bottom to top are manufactured; s8, according to the series of isochronous stratigraphic slices from bottom to top made in the step S7, calculating root-mean-square amplitude attributes to obtain a series of plane root-mean-square amplitude attribute diagrams of all periods from bottom to top; and S9, delineating the distribution range of the sand-rich deepwater fan on the plane according to the plane root mean square amplitude attribute graph of each period in the step S8 and the strong amplitude distribution range.

Description

Technical Field

[0001] This invention relates to a rapid evaluation method, apparatus, medium, and equipment for identifying sand-rich areas in deepwater fans at the edge of continental shelves, belonging to the field of marine oil and gas exploration technology. Background Technology

[0002] Deepwater oil and gas exploration has always been one of the hottest areas in global conventional oil and gas exploration. In the past decade, deepwater fan oil and gas discoveries have accounted for more than 40% of global oil and gas discoveries, indicating enormous exploration potential. Passive continental margin basins are the main battleground for deepwater oil and gas exploration. They develop a typical three-unit geomorphological structure of shelf-slope-deep-sea plain. The gravity flow sedimentary system developed on the slope-deep-sea plain is a key reservoir for deepwater oil and gas exploration. As a product of the deepwater gravity flow system, deepwater fans are high-quality targets for deepwater oil and gas exploration and a focus of attention for both academia and industry.

[0003] Based on differences in sediment grain size, four different types of deep-water fans can be developed: gravelly, sandy, sand-mud mixed, and muddy. Among them, sandy deep-water fans have a high percentage of sandstone content, good sand body connectivity, and relatively homogeneous reservoirs, making them high-quality stratigraphic-lithological trap exploration targets. It is generally believed that the formation of sandy deep-water fans is controlled by multiple factors, including sediment supply, topographic conditions, and sea-level rise and fall. However, at present, the formation, evolution, and sand content prediction of deep-water fans at the shelf margin mainly rely on traditional sequence stratigraphy and seismic sedimentology research methods to identify sequence boundaries and the sequence stratigraphic units constrained by these boundaries to study deep-water fans. The lack of quantitative characterization methods has led to an unclear relationship between changes in shelf margin topography and sediment supply and sedimentary patterns in deep-water areas of the continental slope, resulting in insufficient accuracy in predicting the sand content of deep-water fan sedimentary systems in continental slopes and deep-water basins. Summary of the Invention

[0004] To address the aforementioned technical problems, this invention provides a rapid evaluation method, apparatus, medium, and equipment for determining sand-rich areas of deep-water fans at the shelf margin. This method is computationally simple, easy to operate, and can intuitively, effectively, and quantitatively characterize the sedimentary evolution process of the shelf margin at different periods. It provides guidance for rapidly evaluating deep-water sedimentary systems in well-free / well-poor areas and predicting the distribution areas of sand-rich deep-water fans.

[0005] To achieve the above objectives, the present invention adopts the following technical solution: A rapid evaluation method for identifying sand-rich zones in deepwater fans at the shelf margin includes: S1: Acquire seismic data and select typical seismic reflection profiles along the source direction at the edge of the continental shelf; S2: Based on the seismic reflection termination relationship and typical seismic reflection profiles, we will identify seismic sequence boundaries and establish a sequence stratigraphic framework for the shelf margin. S3: Identify a series of shelf slope breakpoints on and between seismic sequence boundaries in step S2; S4: Connect the series of shelf slope inflection points in step S3 and record the time value T of the shelf slope inflection points; S5: Based on step S4, select shelf slope breakpoints on or between seismic sequence boundaries from bottom to top, and calculate their vertical accretion time thickness difference H. S6: Based on H calculated in step S5, determine the migration type of the shelf edge slope break trajectory; S7: Select the descending shelf slope break migration trajectory segment from the migration type determined in step S6, and make a series of isochronous stratigraphic slices S1, S2, S3... from bottom to top; S8: Based on a series of bottom-up isochronous stratigraphic slices produced in step S7, calculate the root mean square amplitude attribute to obtain a series of bottom-up plane root mean square amplitude attribute maps for each period. S9: Based on the root mean square amplitude attribute map of the plane at each period in step S8, delineate the distribution range of sand-rich deep-water fans on the plane according to the distribution range of strong amplitude.

[0006] The rapid evaluation method for determining the sand-rich area of ​​the deep-water fan at the edge of the continental shelf, preferably, involves, in step S1, using seismic interpretation platform software including PaleoScan or Petrel, selecting seismic reflection profiles with typical continental shelf-slope-deep-water basin structures in the seismic work area based on the seismic profile reflection characteristics and structure.

[0007] In the rapid evaluation method for determining the sand-rich area of ​​the deep-water fan at the edge of the continental shelf, preferably, in step S3, the continental shelf slope break point refers to the first point at the edge of the continental shelf where the topographic slope changes significantly.

[0008] The rapid evaluation method for determining sand-rich areas of deepwater fans at the shelf edge, preferably, in step S5, uses the following formula to calculate the vertical accretion time thickness difference H: H=T1-T2 In the formula, T1 and T2 are the depths of the bottom and top shelf slope inflection points, respectively.

[0009] The rapid evaluation method for determining the sand-rich area of ​​the deep-water fan at the edge of the continental shelf, preferably includes the following migration types in step S6: flat type (H≈0), rising type (H>0), and falling type (H<0).

[0010] The rapid evaluation method for determining the sand-rich area of ​​the deep-water fan at the edge of the continental shelf, preferably, in step S8, extracts the root mean square amplitude attributes of the upper and lower 3ms time windows from the time-series slices in step S7 to obtain the plane root mean square amplitude attribute map for each period.

[0011] A second aspect of the present invention provides a rapid evaluation device for determining sand-rich zones in deepwater fans at the edge of the continental shelf, comprising: The first processing unit is used to acquire seismic data and select typical seismic reflection profiles along the source direction at the edge of the continental shelf. The second processing unit is used to identify seismic sequence boundaries based on typical seismic reflection profiles according to seismic reflection termination relationships, and to establish a sequence stratigraphic framework for the shelf margin region. The third processing unit is used to identify a series of shelf slope breakpoints on and between seismic sequence interfaces in the second processing unit. The fourth processing unit is used to connect a series of shelf slope inflection points in the third processing unit and record the time value T of the shelf slope inflection points; The fifth processing unit is used to calculate the vertical accretion time thickness difference H of the shelf slope breakpoints selected from the bottom up on or between seismic sequence interfaces according to the fourth processing unit. The sixth processing unit is used to determine the migration type of the shelf edge slope break trajectory based on H calculated by the fifth processing unit; The seventh processing unit is used to select the descending shelf slope break migration trajectory segment from the migration type determined by the sixth processing unit and to produce a series of isochronous stratigraphic slices S1, S2, S3... from bottom to top; The eighth processing unit is used to calculate the root mean square amplitude attribute based on a series of bottom-up isochronous stratigraphic slices produced in the seventh processing unit, and to obtain a series of bottom-up plane root mean square amplitude attribute maps for each period. The ninth processing unit is used to delineate the distribution range of sand-rich deep-water fans on the plane based on the root mean square amplitude attribute map of each period in the eighth processing unit and the distribution range of strong amplitude.

[0012] A third aspect of the present invention provides a computer-readable storage medium having a computer program stored thereon, wherein the computer program, when executed by a processor, implements the steps of the rapid evaluation method for determining sand-rich areas of deep-water fans at the shelf margin as described in any of the preceding claims.

[0013] A fourth aspect of the present invention provides a computer device, including a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor executes the computer program to implement the steps of the rapid evaluation method for determining the sand-rich area of ​​the deep-water fan at the shelf margin as described in any of the preceding claims.

[0014] The present invention has the following advantages due to the adoption of the above technical solutions: 1) The method of the present invention is easy to operate, convenient to calculate, and highly feasible. The calculated data can be read from any seismic profile along the continental slope along the sediment source. It is applicable to three-dimensional seismic data in the time domain / depth domain and can quickly and quantitatively characterize the evolution law of continental shelf edge slope break in different sedimentary periods.

[0015] 2) Based on the quantitative characterization of shelf slope migration trajectory, combined with stratigraphic slicing technology and root mean square amplitude attribute comprehensive analysis, this invention can quickly determine whether the continental slope and deep-water basin are prone to forming sand-rich deep-water fans in different sedimentary periods, and further clarify the vertical development segments and planar distribution range of sand-rich deep-water fans, solving the problem of difficulty in predicting sand-rich deep-water fans in areas with few or no wells. It is especially suitable for the rapid evaluation of deep-water exploration areas at the edge of the shelf with low exploration level and relatively scarce data. Attached Figure Description

[0016] Figure 1 This is a typical seismic profile selected for this invention; Figure 2 A typical sequence stratigraphic framework profile of the continental shelf margin established for this invention; Figure 3 This invention is aimed at Figure 2 A series of shelf slope inflection points were identified; Figure 4 This invention is aimed at Figure 3 A schematic diagram of the migration trajectory types of the shelf edge in each segment, based on the vertical accretion thickness, after identifying the shelf slope inflection points; Figure 5 This invention is aimed at Figure 4 A schematic diagram of isochronous slices created from a defined descending migration trajectory segment; Figure 6 This invention is aimed at Figure 5 A series of root mean square amplitude attribute maps extracted from a defined isochronous slice; Figure 7 This invention is aimed at Figure 6 The distribution range of sand-rich deepwater fans delineated by a series of extracted root mean square amplitude attribute maps; Figure 8 This invention is aimed at Figure 3 The time value T recorded at the shelf slope inflection point; Figure 9 This invention is aimed at Figure 3 The vertical accumulation time thickness difference H is calculated from the time value of the shelf slope inflection point. Detailed Implementation

[0017] To make the objectives, technical solutions, and advantages of this invention clearer, the technical solutions of this invention are described clearly and completely below. Obviously, the described embodiments are only some, not all, of the embodiments of this invention. All other embodiments obtained by those skilled in the art based on the embodiments of this invention without creative effort are within the scope of protection of this invention.

[0018] Unless otherwise defined, the technical or scientific terms used in this invention shall have the ordinary meaning understood by one of ordinary skill in the art to which this invention pertains. The terms "first," "second," "third," "fourth," and similar terms used in this invention do not indicate any order, quantity, or importance, but are merely used to distinguish different components. Terms such as "comprising" or "including" mean that the element or object preceding the word encompasses the elements or objects listed following the word and their equivalents, without excluding other elements or objects. Terms such as "connected" or "linked" are not limited to physical or mechanical connections, but can include electrical connections, whether direct or indirect.

[0019] For ease of description, spatial relative terms may be used in the text to describe the relationship of one element or feature relative to another element or feature as shown in the figure. These relative terms include, for example, "inside," "outside," "middle," "outer," "below," "above," etc. Such spatial relative terms are intended to include different orientations of the device in use or operation, other than those depicted in the figure.

[0020] Currently, the formation, evolution, and sand-richness prediction of deep-water fans at the shelf margin mainly rely on traditional sequence stratigraphy and seismic sedimentology methods to identify sequence boundaries and the sequence stratigraphic units constrained by these boundaries to study deep-water fans. However, the lack of quantitative characterization methods has resulted in an unclear relationship between changes in shelf margin topography and sediment supply and sedimentary patterns in deep-water areas of the continental slope. Consequently, the prediction of sand-richness of deep-water fan sedimentary systems in continental slopes and deep-water basins is not accurate enough.

[0021] Based on the above-mentioned technical problems, the present invention provides a rapid evaluation method, apparatus, medium and equipment for determining the sand-rich area of ​​deep-water fans at the shelf margin. The method is simple to calculate and easy to operate, and can intuitively, effectively and quantitatively characterize the sedimentary evolution process of the shelf margin at different periods, providing guidance for the rapid evaluation of deep-water sedimentary systems in well-free / well-poor areas and the prediction of sand-rich deep-water fan distribution areas.

[0022] like Figure 1 As shown, the rapid evaluation method for determining sand-rich areas of deepwater fans at the shelf margin provided by this invention includes the following specific steps: Step 1: Profile Selection: Using seismic interpretation platform software such as PaleoScan or Petrel, select seismic reflection profiles with typical shelf-slope-deep-water basin structures in the seismic work area based on the seismic profile reflection characteristics and structure. For example... Figure 1 As shown.

[0023] Step 2: Framework Establishment: Based on seismic reflection characteristics, identify typical sequence boundaries, such as (SB1-SB5), and establish a sequence stratigraphic framework for the shelf margin region. Figure 2 As shown.

[0024] Step 3: Shelf Slope Breakpoint Identification: Identify a series of shelf slope breakpoints (i.e., the first point at the shelf edge where the topographic slope changes significantly) on and between seismic sequence boundaries identified in Step 2. For example... Figure 3 As shown.

[0025] Step 4: Depth Reading: Connect the series of shelf slope inflection points from Step 3 and record the time value T of each inflection point. As shown in Table 1.

[0026] Step 5: Determining the thickness of the vertical product time: For Figure 8 The time value is used to calculate the difference in vertical accumulation time thickness H between different layers, where H = T1 - T2, and T1 and T2 are the inflection points of the bottom and top shelf slopes, respectively. Figure 8 As shown. Specifically, according to step S4, shelf slope breakpoints on or between seismic sequence boundaries are selected from bottom to top, and their vertical accretion time thickness difference H is calculated.

[0027] Step 6: Type Identification: Based on the quantitative characterization data obtained in Step 5, determine the migration type of shelf edge slope break trajectories on or between different interfaces. Migration types include: straight type (H≈0), ascending type (H>0), and descending type (H<0). Figure 4 As shown.

[0028] Step 7: Stratigraphic Slicing: The strata slices from Step 6... Figure 4 Isochronous sections were prepared for the second phase of the descending migration trajectory segment, resulting in four isochronous stratigraphic sections (S1, S2, S3, and S4) from bottom to top. The section locations are shown below. Figure 5 As shown.

[0029] Step 8: RMS Attributes: Based on the series of bottom-up isochronous stratigraphic slices created in Step 7, extract the root mean square amplitude attributes within 3ms time windows to obtain a series of bottom-up planar root mean square amplitude attribute maps for each period. For example... Figure 6 As shown.

[0030] Step 9: Delineation of the Scope; Based on the root mean square amplitude attribute maps of the plane at each period in Step 8, delineate the plane distribution area of ​​the sand-rich deep-water fan according to the strong amplitude distribution range of the continental slope-deep-water basin. For example... Figure 7 As shown.

[0031] A second aspect of the present invention provides a rapid evaluation device for determining sand-rich zones in deepwater fans at the edge of the continental shelf, comprising: The first processing unit is used to acquire seismic data and select typical seismic reflection profiles along the source direction at the edge of the continental shelf. The second processing unit is used to identify seismic sequence boundaries based on typical seismic reflection profiles according to seismic reflection termination relationships, and to establish a sequence stratigraphic framework for the shelf margin region. The third processing unit is used to identify a series of shelf slope breakpoints on and between seismic sequence interfaces in the second processing unit. The fourth processing unit is used to connect a series of shelf slope inflection points in the third processing unit and record the time value T of the shelf slope inflection points; The fifth processing unit is used to calculate the vertical accretion time thickness difference H of the shelf slope breakpoints selected from the bottom up on or between seismic sequence interfaces according to the fourth processing unit. The sixth processing unit is used to determine the migration type of the shelf edge slope break trajectory based on H calculated by the fifth processing unit; The seventh processing unit is used to select the descending shelf slope break migration trajectory segment from the migration type determined by the sixth processing unit and to produce a series of isochronous stratigraphic slices S1, S2, S3... from bottom to top; The eighth processing unit is used to calculate the root mean square amplitude attribute based on a series of bottom-up isochronous stratigraphic slices produced in the seventh processing unit, and to obtain a series of bottom-up plane root mean square amplitude attribute maps for each period. The ninth processing unit is used to delineate the distribution range of sand-rich deep-water fans on the plane based on the root mean square amplitude attribute map of each period in the eighth processing unit and the distribution range of strong amplitude.

[0032] A third aspect of the present invention provides a computer-readable storage medium having a computer program stored thereon, wherein the computer program, when executed by a processor, implements the steps of the rapid evaluation method for determining sand-rich areas of deep-water fans at the shelf margin as described in any of the preceding claims.

[0033] A fourth aspect of the present invention provides a computer device, including a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor executes the computer program to implement the steps of the rapid evaluation method for determining the sand-rich area of ​​the deep-water fan at the shelf margin as described in any of the preceding claims.

[0034] This invention is described based on flowcharts and / or block diagrams of methods, apparatus (systems), and computer program products according to specific embodiments. It should be understood that each block of the flowcharts and / or block diagrams, and combinations of blocks in the flowcharts and / or block diagrams, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, special-purpose computer, embedded processor, or other programmable data processing device to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing device, generate instructions for implementing the flowcharts and / or block diagrams. Figure 1 a process or multiple processes and / or boxes Figure 1 A device that provides the functions specified in one or more boxes.

[0035] These computer program instructions may also be stored in a computer readable memory that can direct a computer or other programmable data processing device to work in a specific manner, so that the instructions stored in the computer readable memory produce an article of manufacture comprising an instruction device, which implements the process Figure 1 a process or multiple processes and / or boxes Figure 1 The function specified in one or more boxes.

[0036] These computer program instructions can also be loaded onto a computer or other programmable data processing device so that a series of operational steps are executed on the computer or other programmable device to produce a computer-implemented process, thereby providing the instructions executed on the computer or other programmable device for implementing the process. Figure 1 a process or multiple processes and / or boxes Figure 1 A step that specifies a function in one or more boxes.

[0037] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A rapid evaluation method for identifying sand-rich zones in deepwater fans at the edge of the continental shelf, characterized in that, include: S1: Acquire seismic data and select typical seismic reflection profiles along the source direction at the edge of the continental shelf; S2: Based on the seismic reflection termination relationship and typical seismic reflection profiles, we will identify seismic sequence boundaries and establish a sequence stratigraphic framework for the shelf margin. S3: Identify a series of shelf slope breakpoints on and between seismic sequence boundaries in step S2; S4: Connect the series of shelf slope inflection points in step S3 and record the time value T of the shelf slope inflection points; S5: Based on step S4, select shelf slope breakpoints on or between seismic sequence boundaries from bottom to top, and calculate their vertical accretion time thickness difference H. S6: Based on H calculated in step S5, determine the migration type of the shelf edge slope break trajectory; S7: Select the descending shelf slope break migration trajectory segment from the migration type determined in step S6, and make a series of isochronous stratigraphic slices S1, S2, S3... from bottom to top; S8: Based on a series of bottom-up isochronous stratigraphic slices produced in step S7, calculate the root mean square amplitude attribute to obtain a series of bottom-up plane root mean square amplitude attribute maps for each period. S9: Based on the root mean square amplitude attribute map of the plane at each period in step S8, delineate the distribution range of sand-rich deep-water fans on the plane according to the distribution range of strong amplitude.

2. The rapid evaluation method for determining sand-rich areas of deepwater fans at the shelf margin according to claim 1, characterized in that, In step S1, seismic interpretation platform software, including PaleoScan or Petrel, is used to select seismic reflection profiles with typical shelf-slope-deep-water basin structures in the seismic work area based on the seismic profile reflection characteristics and structure.

3. The rapid evaluation method for determining sand-rich areas of deepwater fans at the shelf margin according to claim 1, characterized in that, In step S3, the shelf slope break point refers to the first point at the edge of the shelf where the topographic slope changes significantly.

4. The rapid evaluation method for determining sand-rich areas of deepwater fans at the shelf margin according to claim 1, characterized in that, In step S5, the formula for calculating the vertical accumulation time thickness difference H is as follows: H=T1-T2 In the formula, T1 and T2 are the depths of the bottom and top shelf slope inflection points, respectively.

5. The rapid evaluation method for determining sand-rich areas of deepwater fans at the shelf margin according to claim 1, characterized in that, In step S6, the migration types include: flat (H≈0), rising (H>0), and falling (H<0).

6. The rapid evaluation method for determining sand-rich areas of deepwater fans at the shelf margin according to claim 1, characterized in that, In step S8, the root mean square amplitude attributes of the upper and lower 3ms time windows are extracted from the time-series slices in step S7 to obtain the plane root mean square amplitude attribute map for each period.

7. A rapid evaluation device for determining sand-rich zones in deepwater fans at the edge of continental shelves, characterized in that, include: The first processing unit is used to acquire seismic data and select typical seismic reflection profiles along the source direction at the edge of the continental shelf. The second processing unit is used to identify seismic sequence boundaries based on typical seismic reflection profiles according to seismic reflection termination relationships, and to establish a sequence stratigraphic framework for the shelf margin region. The third processing unit is used to identify a series of shelf slope breakpoints on and between seismic sequence interfaces in the second processing unit. The fourth processing unit is used to connect a series of shelf slope inflection points in the third processing unit and record the time value T of the shelf slope inflection points; The fifth processing unit is used to calculate the vertical accretion time thickness difference H of the shelf slope breakpoints selected from the bottom up on or between seismic sequence interfaces according to the fourth processing unit. The sixth processing unit is used to determine the migration type of the shelf edge slope break trajectory based on H calculated by the fifth processing unit; The seventh processing unit is used to select the descending shelf slope break migration trajectory segment from the migration type determined by the sixth processing unit and to produce a series of isochronous stratigraphic slices S1, S2, S3... from bottom to top; The eighth processing unit is used to calculate the root mean square amplitude attribute based on a series of bottom-up isochronous stratigraphic slices produced in the seventh processing unit, and to obtain a series of bottom-up plane root mean square amplitude attribute maps for each period. The ninth processing unit is used to delineate the distribution range of sand-rich deep-water fans on the plane based on the root mean square amplitude attribute map of each period in the eighth processing unit and the distribution range of strong amplitude.

8. A computer-readable storage medium having a computer program stored thereon, characterized in that, When the computer program is executed by the processor, it implements the steps of the rapid evaluation method for determining sand-rich areas of deep-water fans at the shelf margin as described in any one of claims 1-6.

9. A computer device, comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, characterized in that, When the processor executes the computer program, it implements the steps of the rapid evaluation method for determining sand-rich areas of deep-water fans at the shelf margin as described in any one of claims 1-6.

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