Method, device, medium and equipment for identifying the largest lake flooding surface on earthquakes

Abstract

The present invention relates to a method, device, medium and equipment for identifying a maximum lake flooding surface on a seismic basis. The method comprises the following steps: selecting a well that encounters a target layer, calculating a Fischer diagram of the well, and setting a Fischer diagram of the target layer; setting a first depth value as the maximum lake flooding surface depth displayed on the well; determining a main provenance direction of the target layer during its deposition period; cutting a seismic profile passing through the well along the main provenance direction; inputting the top and bottom interfaces of the target layer into the seismic profile; calculating a stratigraphic volume of the seismic profile; setting a second depth value as the maximum lake flooding surface depth identified by a Wheeler domain profile; setting a third maximum amplitude point as the maximum lake flooding surface depth point determined on the seismic profile; finding the third maximum amplitude point on a vertical line based on the depth value of the third maximum amplitude point; tracing a seismic event on the seismic profile with the third maximum amplitude point as the starting point, and obtaining an interface that is the maximum lake flooding surface of a target layer on the seismic profile.

Description

Technical Field

[0001] The present invention relates to a method, device, medium and equipment for identifying the maximum lake flooding surface on earthquakes, belonging to the technical field of oil and gas exploration. Background Art

[0002] Sequence stratigraphic division is essential in oil and gas exploration. Explorators typically identify sequence interfaces through contact relationships such as truncation, downlap, and onlap of seismic events. Sequence top and bottom interfaces are often unconformities, with angular unconformities being the most prominent, making them relatively easy to identify. Identifying the maximum lake flooding surface within a sequence requires finding the point of maximum onlap, where the lake level crosses the maximum slope break. The event traced along this point is the maximum lake flooding surface, characterized by typical downlap above and serial onlap below. Identifying the maximum lake flooding surface within a sequence is crucial for delineating sequence systems tracts, understanding sedimentary infill evolution, identifying condensed sections, and evaluating source rock distribution.

[0003] Among existing methods, some scholars use lithologic methods to identify the maximum lake flooding surface. They believe that during the development of the maximum lake flooding surface, lake basin sediments were fine-grained, primarily composed of mudstone and shale interbedded with siltstone. The maximum lake flooding surface can be determined based on the location of these lithologies or lithologic combinations. However, in oil and gas exploration, most wells do not obtain systematic core data, making it difficult to identify the maximum lake flooding surface through intuitive lithologic observation. Some scholars use the significant amplitude difference between sonic and resistivity logging curves to determine organic carbon content, locating the maximum lake flooding surface corresponding to areas with high organic carbon content. Some scholars believe that the maximum lake flooding surface on logging curves is often characterized by high natural gamma ray, low resistivity, and flat natural potential. However, identifying the maximum lake flooding surface based solely on logging curve characteristics still suffers from multiple interpretations and lacks a reflection of the characteristics of drilling sedimentary cycles. In areas without drilling, some scholars believe that mudstone and shale deposits near the largest lake flooding surface exhibit low-density, low-velocity characteristics, creating a significant impedance difference with the surrounding rocks above and below. Combined with the lower onlap and upper onlap characteristics, the seismic reflection characteristics are distinct and easy to identify. However, in areas with few drilling wells, complex faults, and poor seismic data quality, identifying the largest lake flooding surface based on seismic reflection characteristics is difficult.

[0004] In summary, existing technical methods mainly rely on separate lithologic descriptions, separate well logging curves, or separate seismic reflection characteristics to identify the maximum lake flooding surface. These methods all suffer from the problems of lack of reflection of sedimentary cycle characteristics, insufficient mining of research data, high requirements for tectonic movement in the study area, or high requirements for the quality of seismic data. Overall, there is a lack of a systematic method to reflect the characteristics of drilling and seismic sedimentary cycles and to quantitatively track the location of the maximum lake flooding surface in seismic data. Summary of the Invention

[0005] In response to the above technical problems, the present invention provides a method, device, medium and equipment for identifying the maximum lake flooding surface in seismic data. The method is based on the Fischer curve and the Wheeler domain to identify the maximum lake flooding surface in seismic data. The identification method of the present invention can reduce the requirements for drilling coring, avoid the multi-solution problem of relying solely on logging curves to identify the maximum lake flooding surface, and reduce the requirements for seismic data quality. It can achieve the purpose of quantitative identification in drilling and quantitative tracking of the position of the maximum lake flooding surface in seismic data, and provide an effective basis for the division of sequence system domains, sedimentary evolution processes, condensation section identification and source rock distribution prediction.

[0006] To achieve the above object, the present invention adopts the following technical solutions:

[0007] A method for identifying the maximum lake flooding surface based on earthquakes comprises the following steps:

[0008] Select the well that encounters the target layer, calculate the Fischer diagram of the well, and set the Fischer diagram of the target layer;

[0009] According to the Fischer diagram of the target layer, find the first maximum amplitude point and the first depth value of the leftward fluctuation on the Fischer diagram of the target layer, and set the first depth value to the maximum lake flooding depth shown on the drilling surface;

[0010] Determine the main provenance direction of the target interval during its deposition period;

[0011] In the 3D seismic work area, a seismic section through the well is cut along the main provenance direction;

[0012] Input the top and bottom interfaces of the target layer in the seismic profile;

[0013] Calculate the stratigraphic volume of the seismic section using the top and bottom interfaces as constraints;

[0014] Observe the fluctuation of the stratigraphic body, find the second maximum amplitude point and second depth value of the stratigraphic body in the upstream direction of the main source, and set the second depth value as the maximum lake flooding depth identified by the Wheeler domain profile;

[0015] Draw a vertical line on the seismic section with the wellhead, the length of which is equal to the width of the seismic section, project the first and second maximum amplitude points onto the vertical line, and set the third maximum amplitude point as the maximum lake flooding depth point determined on the seismic section;

[0016] The third maximum amplitude point is found from the vertical line according to its depth value. Taking the third maximum amplitude point as the starting point, the seismic event axis is traced on the seismic profile. The obtained interface is the maximum lake flooding surface of a certain target layer segment on the seismic profile.

[0017] The method for identifying the maximum lake flooding surface on a seismic basis preferably comprises the following steps: selecting a well that has encountered a target layer, calculating the Fischer diagram of the well, and setting the Fischer diagram of the target layer.

[0018] A well that encounters a target layer is selected, and the Fischer diagram of the well is calculated using the gamma logging curve of the well and according to the Fischer diagram calculation method, and the Fischer diagram of the target layer is set.

[0019] The method for identifying the maximum lake flooding surface on seismic data preferably includes the following steps: finding the first maximum amplitude point and the first depth value of the leftward fluctuation on the Fischer diagram of the target layer according to the Fischer diagram of the target layer, and setting the first depth value to the maximum lake flooding surface depth displayed on the wellbore.

[0020] According to the Fischer diagram of the target layer, observe the fluctuation of the Fischer diagram of the target layer in the target layer section. Set the target layer Fischer diagram to the left to indicate that the accommodating space increases, and the target layer Fischer diagram to the right to indicate that the accommodating space decreases. Find the first maximum amplitude point and the first depth value of the leftward fluctuation on the Fischer diagram of the target layer, and set the first depth value to the maximum lake flooding depth displayed on the drilling.

[0021] The method for identifying the maximum lake flooding surface on seismic basis, preferably, determines the main provenance direction of the target interval during its deposition period, including the following steps:

[0022] Based on regional geological background research and literature survey methods, the main provenance direction of the target layer during the deposition period is determined.

[0023] The method for identifying the maximum lake flooding surface on a seismic basis preferably calculates the stratigraphic volume of the seismic section using the top and bottom interfaces as constraints, and includes the following steps:

[0024] With the top and bottom interfaces as constraints, the stratigraphic volume of the seismic section is calculated using OpendTect software.

[0025] The method for identifying the maximum lake flooding surface on a seismic basis preferably comprises observing the fluctuation of the stratigraphic body, finding the second maximum amplitude point and the second depth value of the stratigraphic body fluctuation in the upstream direction of the main provenance, and setting the second depth value as the maximum lake flooding surface depth identified by the Wheeler domain profile, including the following steps:

[0026] Display the stratigraphic body of the seismic profile in the Wheeler domain view and observe the fluctuation of the stratigraphic body. The fluctuation of the stratigraphic body upstream of the main provenance indicates an increase in the accommodative space, while the fluctuation of the stratigraphic body downstream of the main provenance indicates a decrease in the accommodative space. Find the second maximum amplitude point and second depth value of the stratigraphic body fluctuation upstream of the main provenance, and set the second depth value as the maximum lake flooding depth identified by the Wheeler domain profile.

[0027] In the method for identifying the maximum lake flooding surface on an earthquake, preferably, the method for tracing the seismic event on the seismic profile adopts the maximum extreme point method, that is, tracing the line along the maximum amplitude on the seismic event.

[0028] A second aspect of the present invention provides a device for identifying the maximum lake flooding surface based on earthquakes, comprising:

[0029] The first processing unit is used to select a well that encounters a target layer, calculate the Fischer diagram of the well, and set the Fischer diagram of the target layer;

[0030] The second processing unit is configured to find a first maximum amplitude point and a first depth value of a leftward fluctuation on the Fischer diagram of the target layer according to the Fischer diagram of the target layer, and set the first depth value to be a maximum lake flooding depth displayed on the well;

[0031] The third processing unit is used to determine the main provenance direction of the target layer during its deposition period;

[0032] The fourth processing unit is used to cut a seismic profile through the well along the main source direction in the 3D seismic work area;

[0033] a fifth processing unit, for inputting the top and bottom interfaces of the target layer in the seismic profile;

[0034] a sixth processing unit for calculating the stratigraphic volume of the seismic section with the top and bottom interfaces as constraints;

[0035] The seventh processing unit is used to observe the fluctuation of the stratigraphic body, find the second maximum amplitude point and the second depth value of the stratigraphic body in the upstream direction of the main source, and set the second depth value as the maximum lake flooding depth identified by the Wheeler domain profile;

[0036] an eighth processing unit, configured to draw a perpendicular line on the seismic profile through the wellhead, wherein the length of the perpendicular line is equal to the width of the seismic profile, project the first maximum amplitude point and the second maximum amplitude point onto the perpendicular line, and set the third maximum amplitude point as the maximum lake flooding depth point determined on the seismic profile;

[0037] The ninth processing unit is used to find the third maximum amplitude point according to the depth value of the third maximum amplitude point on the vertical line, and to track the seismic phase axis on the seismic profile with the third maximum amplitude point as the starting point. The obtained interface is the maximum lake flooding surface of a certain target layer segment on the seismic profile.

[0038] A third aspect of the present invention provides a computer-readable storage medium having a computer program stored thereon, which, when executed by a processor, implements the steps of the above-mentioned method for identifying the maximum lake flooding surface on earthquakes.

[0039] A fourth aspect of the present invention provides a computer device comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein when the processor executes the computer program, the steps of the above-mentioned method for identifying the maximum lake flooding surface on earthquakes are implemented.

[0040] The present invention has the following advantages due to the adoption of the above technical solution:

[0041] 1. The present invention calculates the Fischer curve using the gamma-ray logging curve (GR curve) in drilling, and combines it with the logging lithology data to reflect the sedimentary cycle characteristics of the drilling, and can more effectively identify the depth position of the maximum lake flooding surface in a sequence in drilling.

[0042] 2. The present invention makes full use of geological analysis results, uses seismic interpretation horizons as constraints, and calculates the Wheeler characteristics of the target layer. This can reflect the sedimentary cycle characteristics on the seismic profile and effectively identify the maximum lake flooding depth within a sequence on the seismic profile.

[0043] 3. The present invention integrates logging data, well logging curves and seismic data, fully utilizes the results of geological analysis, and mines geophysical information containing information on the maximum lake flooding surface. It reduces the requirements for the quality of seismic data (only the phase axis of the seismic data needs to be identified), and can achieve accurate estimation of the location of the maximum lake flooding surface within the sequence.

[0044] 4. In areas with only a small number of wells, the identification method of the present invention can effectively determine the location of the maximum lake flooding surface, which is of great significance for the division of sequence system domains, sedimentary evolution processes, condensation section identification and source rock distribution prediction. The identification method of the present invention can be widely used in the quantitative determination and system of the maximum lake flooding surface combined with well-seismic data. BRIEF DESCRIPTION OF THE DRAWINGS

[0045] Figure 1 This is a flow chart of a method for identifying the largest lake flooding surface based on earthquakes, provided by one embodiment of the present invention;

[0046] Figure 2 Schematic diagram of obtaining a Fischer curve Fa using a gamma logging curve of well A provided in this embodiment of the present invention;

[0047] Figure 3 1 is a schematic cross-sectional view of a seismic profile S in the main source direction of a well and a stratigraphic body H provided by this embodiment of the present invention;

[0048] Figure 4 1 is a schematic diagram showing a layer body H of a through-drilling seismic profile in the Wheeler domain provided by this embodiment of the present invention;

[0049] Figure 5 Schematic diagram of the maximum lake flooding depth position point P3 determined by combining well-seismic analysis according to this embodiment of the present invention;

[0050] Figure 6 This is a schematic diagram of tracking the maximum lake flooding surface MFS on the seismic section based on point P3 provided by this embodiment of the present invention. DETAILED DESCRIPTION

[0051] To make the objectives, technical solutions, and advantages of the present invention more clear, the technical solutions of the present invention are described clearly and completely below. Obviously, the embodiments described are only some of the embodiments of the present invention, not all of them. All other embodiments derived by ordinary persons in this field based on the embodiments of the present invention without creative effort are within the scope of protection of the present invention.

[0052] The present invention addresses the problems of existing technical methods that mainly use lithologic descriptions, well logging curves or seismic reflection characteristics alone to identify the maximum lake flooding surface, all of which lack reflection of sedimentary cycle characteristics, insufficient research data mining, high requirements for tectonic movement in the study area or high requirements for seismic data quality. A method for identifying the maximum lake flooding surface in seismic terms is proposed. The method is based on the Fischer curve and the Wheeler domain to identify the maximum lake flooding surface in seismic terms. The identification method of the present invention can reduce the requirements for drilling coring, avoid the multi-solution problem of relying solely on well logging curves to identify the maximum lake flooding surface, and reduce the requirements for seismic data quality. The purpose of quantitative identification in drilling and quantitative tracking of the position of the maximum lake flooding surface in seismic terms is achieved, providing an effective basis for sequence system domain division, sedimentary evolution process, condensation section identification and source rock distribution prediction.

[0053] like Figure 1 As shown, this embodiment provides a method for identifying the maximum lake flooding surface based on earthquakes based on the Fischer curve and the Wheeler domain, including the following steps:

[0054] 1) Select well A that encounters the target layer, use the GR curve (gamma logging curve) of well A, calculate the Fischer diagram of well A according to the Fischer diagram calculation method (known method), and set the Fischer diagram of the target layer to Fa;

[0055] 2) Based on the Fa obtained in step 1), observe the fluctuation of the Fa diagram in the target layer. Set Fa fluctuation to the left to indicate an increase in the accommodative space, and Fa fluctuation to the right to indicate a decrease in the accommodative space. Find the point P1 with the maximum amplitude of the leftward fluctuation on Fa, and its depth value is D1. Set D1 to the maximum lake flooding depth shown on well A.

[0056] 3) Determine the main provenance direction of the target interval during its depositional period based on regional geological background research and literature review methods;

[0057] 4) In the 3D seismic area, cut the seismic section S through the well A along the main provenance direction;

[0058] 5) Input the top and bottom interfaces Li (i=1, 2, 3, ...) of the target layer in the seismic profile S;

[0059] 6) Using the top and bottom interfaces Li (i = 1, 2, 3, ...) as constraints, calculate the horizon volume H of the profile S using OpendTect software;

[0060] 7) Display the horizon H obtained in step 6) in the Wheeler domain view and observe the fluctuation of the horizon H. Fluctuation of the horizon H upstream of the main provenance indicates an increase in the accommodation space, while fluctuation of the horizon H downstream of the main provenance indicates a decrease in the accommodation space. Find the point P2 with the maximum amplitude of the fluctuation of the horizon H upstream of the main provenance and its depth D2. Set D2 as the maximum lake flooding depth identified by the Wheeler domain profile.

[0061] 8) Draw a perpendicular line W from the wellhead of well A on the seismic profile S. The length of the perpendicular line W is equal to the width of the seismic profile. Project the maximum amplitude points P1 and P2 onto the perpendicular line W. Let P3 be the point of maximum lake flooding depth determined on the seismic profile, and the depth of P3 is D3 = (D1 + D2) / 2.

[0062] 9) From the vertical line W, find point P3 according to the depth value D3. Taking P3 as the starting point, trace the seismic event on the seismic profile S to obtain the interface MFS, which is the maximum lake flooding surface of a certain target layer segment on the seismic profile.

[0063] The seismic event tracking method in step 9) adopts the maximum extreme point method, that is, tracking the line along the maximum amplitude on the seismic event.

[0064] The following describes in detail the method of identifying the maximum lake flooding surface based on the Fischer curve and Wheeler domain in seismic data of the present invention, taking the lake-facies sediments of the Wenchang Formation of the Eocene in the Kaiping Depression of the Pearl River Mouth Basin as a specific example. The specific steps are as follows:

[0065] 1) Well A, which encountered the upper part of the second member of the Wenchang Formation in the Kaiping Sag, was selected as the research object. The Fischer diagram of the Wenchang Formation was calculated using the GR logging curve of Well A. The Fischer diagram of the Wenchang Formation was set as Fa, and the second member was selected as the research target layer.

[0066] 2) Based on the Fischer diagram Fa obtained in step 1), observe the fluctuation of Fa in the second section, find the lowest point P1 of the leftward fluctuation, and read the depth value D1 of point P1 as 3978m. Set D1 to the maximum lake flooding depth shown in the second section of the Wenchang Formation on well A, as shown in Figure 2. Figure 2 As shown;

[0067] 3) Based on regional geological background research and literature research, the main provenance direction of the Wenchang Formation during its deposition period was determined to be northwest-southeast;

[0068] 4) In the 3D seismic area, a seismic profile S is cut through well A along the main provenance direction (northwest-southeast);

[0069] 5) Input the top and bottom interfaces of the Wenchang Group segment L1, L2, L3, L4, L5, and L6 in the seismic profile S;

[0070] 6) Using the top and bottom interfaces L1, L2, L3, L4, L5, and L6 as constraints, the layer volume H of the profile S is calculated using OpendTect software. The results are as follows: Figure 3 As shown;

[0071] 7) Display the horizon H obtained in step 6) in the Wheeler domain view and observe the fluctuation of the horizon H. The fluctuation of the horizon H toward the upstream of the main material source indicates that the accommodation space is increasing, and the fluctuation of the horizon H toward the downstream of the main material source indicates that the accommodation space is decreasing. Find the point P2 with the maximum amplitude of the fluctuation of the horizon H upstream of the main material source. Its depth value D2 is 4320m. Set D2 as the maximum lake flooding depth identified by the Wheeler domain profile, as shown in the figure below. Figure 4 As shown;

[0072] 8) Draw a perpendicular line W from the wellhead of well A on the seismic profile S. The length of the perpendicular line W is equal to the width of the seismic profile. Project the depth points P1 and P2 onto the perpendicular line W. Let P3 be the maximum lake flooding depth point determined on the seismic profile, and the depth value of P3 is D3 = (D1 + D2) / 2. The calculated value of D3 is 4149 m. Figure 5 As shown;

[0073] 9) From the vertical line W, find point P3 according to the depth value D3. Taking P3 as the starting point, trace the seismic event on the seismic profile S to obtain the interface MFS, which is the maximum lake flooding surface of a target layer segment on the seismic profile (the specific application example is segment 2), as shown in the following example: Figure 6 shown.

[0074] According to this embodiment, the position of the maximum lake flooding surface during the lake transgression period of the Wenchang Formation of the Eocene in the Kaiping Sag of the Pearl River Mouth Basin can be more quantitatively understood, thereby guiding oil and gas exploration in the Kaiping Sag.

[0075] A second aspect of the present invention provides a device for identifying the maximum lake flooding surface based on earthquakes, comprising:

[0076] The first processing unit is used to select a well that encounters a target layer, calculate the Fischer diagram of the well, and set the Fischer diagram of the target layer;

[0077] The second processing unit is configured to find a first maximum amplitude point and a first depth value of a leftward fluctuation on the Fischer diagram of the target layer according to the Fischer diagram of the target layer, and set the first depth value to be a maximum lake flooding depth displayed on the well;

[0078] The third processing unit is used to determine the main provenance direction of the target layer during its deposition period;

[0079] The fourth processing unit is used to cut a seismic profile through the well along the main source direction in the 3D seismic work area;

[0080] a fifth processing unit, for inputting the top and bottom interfaces of the target layer in the seismic profile;

[0081] a sixth processing unit for calculating the stratigraphic volume of the seismic section with the top and bottom interfaces as constraints;

[0082] The seventh processing unit is used to observe the fluctuation of the stratigraphic body, find the second maximum amplitude point and the second depth value of the stratigraphic body in the upstream direction of the main source, and set the second depth value as the maximum lake flooding depth identified by the Wheeler domain profile;

[0083] an eighth processing unit, configured to draw a perpendicular line on the seismic profile through the wellhead, wherein the length of the perpendicular line is equal to the width of the seismic profile, project the first maximum amplitude point and the second maximum amplitude point onto the perpendicular line, and set the third maximum amplitude point as the maximum lake flooding depth point determined on the seismic profile;

[0084] The ninth processing unit is used to find the third maximum amplitude point according to the depth value of the third maximum amplitude point on the vertical line, and to track the seismic phase axis on the seismic profile with the third maximum amplitude point as the starting point. The obtained interface is the maximum lake flooding surface of a certain target layer segment on the seismic profile.

[0085] A third aspect of the present invention provides a computer-readable storage medium having a computer program stored thereon, which, when executed by a processor, implements the steps of the above-mentioned method for identifying the maximum lake flooding surface on earthquakes.

[0086] A fourth aspect of the present invention provides a computer device comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein when the processor executes the computer program, the steps of the above-mentioned method for identifying the maximum lake flooding surface on earthquakes are implemented.

[0087] The present invention is described in terms of flowcharts and / or block diagrams of methods, devices (systems), and computer program products according to specific embodiments. It should be understood that each process and / or block in the flowchart and / or block diagram, as well as a combination of processes and / or blocks in the flowchart and / or block diagram, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, a special-purpose computer, an embedded processor, or other programmable data processing device to generate a machine, so that the instructions executed by the processor of the computer or other programmable data processing device generate instructions for implementing the processes in the flowchart and / or block diagram. Figure 1 a process or multiple processes and / or boxes Figure 1 A device that provides the functions specified in a block or multiple blocks.

[0088] 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.

[0089] 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.

[0090] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the various embodiments of the present invention.

Claims

1. A method for identifying the maximum lake flooding area based on earthquakes, characterized in that: The steps include: Select the well that encounters the target layer, calculate the Fischer diagram of the well, and set the Fischer diagram of the target layer; According to the Fischer diagram of the target layer, find the first maximum amplitude point and the first depth value of the leftward fluctuation on the Fischer diagram of the target layer, and set the first depth value to the maximum lake flooding depth shown on the drilling surface; Determine the main provenance direction of the target interval during its deposition period; In the 3D seismic work area, a seismic section through the well is cut along the main provenance direction; Input the top and bottom interfaces of the target layer in the seismic profile; Calculate the stratigraphic volume of the seismic section using the top and bottom interfaces as constraints; Observe the fluctuation of the stratigraphic body, find the second maximum amplitude point and second depth value of the stratigraphic body in the upstream direction of the main source, and set the second depth value as the maximum lake flooding depth identified by the Wheeler domain profile; Draw a vertical line on the seismic section with the wellhead, the length of which is equal to the width of the seismic section, project the first and second maximum amplitude points onto the vertical line, and set the third maximum amplitude point as the maximum lake flooding depth point determined on the seismic section; The third maximum amplitude point is found from the vertical line according to its depth value. Taking the third maximum amplitude point as the starting point, the seismic event axis is traced on the seismic profile. The obtained interface is the maximum lake flooding surface of a certain target layer segment on the seismic profile.

2. The method for identifying the maximum lake flooding surface based on earthquakes according to claim 1, characterized in that: Select a well that encounters a target layer, calculate the Fischer diagram of the well, and set the Fischer diagram of the target layer, including the following steps: A well that encounters a target layer is selected, and the Fischer diagram of the well is calculated using the gamma logging curve of the well and according to the Fischer diagram calculation method, and the Fischer diagram of the target layer is set.

3. The method for identifying the maximum lake flooding surface based on earthquakes according to claim 1, characterized in that: According to the Fischer diagram of the target layer, the first maximum amplitude point and the first depth value of the leftward fluctuation on the Fischer diagram of the target layer are found, and the first depth value is set to the maximum lake flooding depth displayed on the drilling, including the following steps: According to the Fischer diagram of the target layer, observe the fluctuation of the Fischer diagram of the target layer in the target layer section. Set the target layer Fischer diagram to the left to indicate that the accommodating space increases, and the target layer Fischer diagram to the right to indicate that the accommodating space decreases. Find the first maximum amplitude point and the first depth value of the leftward fluctuation on the Fischer diagram of the target layer, and set the first depth value to the maximum lake flooding depth displayed on the drilling.

4. The method for identifying the maximum lake flooding surface based on earthquakes according to claim 1, characterized in that: Determining the main provenance direction of the target interval during its depositional period includes the following steps: Based on regional geological background research and literature survey methods, the main provenance direction of the target layer during the deposition period is determined.

5. The method for identifying the maximum lake flooding surface based on earthquakes according to claim 1, characterized in that: Calculating the stratigraphic volume of a seismic section using the top and bottom interfaces as constraints involves the following steps: With the top and bottom interfaces as constraints, the stratigraphic volume of the seismic section is calculated using OpendTect software.

6. The method for identifying the maximum lake flooding surface based on earthquakes according to claim 1, characterized in that: Observe the fluctuation of the stratigraphic body, find the second maximum amplitude point and second depth value of the stratigraphic body fluctuation upstream of the main provenance, and set the second depth value to the maximum lake flooding depth identified by the Wheeler domain profile, including the following steps: Display the stratigraphic body of the seismic profile in the Wheeler domain view and observe the fluctuation of the stratigraphic body. The fluctuation of the stratigraphic body upstream of the main provenance indicates an increase in the accommodative space, while the fluctuation of the stratigraphic body downstream of the main provenance indicates a decrease in the accommodative space. Find the second maximum amplitude point and second depth value of the stratigraphic body fluctuation upstream of the main provenance, and set the second depth value as the maximum lake flooding depth identified by the Wheeler domain profile.

7. The method for identifying the maximum lake flooding surface based on earthquakes according to claim 1, characterized in that: The method for tracing seismic events on seismic sections adopts the maximum extreme point method, that is, tracing the line along the maximum amplitude on the seismic event.

8. A device for identifying the maximum lake flooding area based on earthquakes, characterized in that: include: The first processing unit is used to select a well that encounters a target layer, calculate the Fischer diagram of the well, and set the Fischer diagram of the target layer; The second processing unit is configured to find a first maximum amplitude point and a first depth value of a leftward fluctuation on the Fischer diagram of the target layer according to the Fischer diagram of the target layer, and set the first depth value to be a maximum lake flooding depth displayed on the well; The third processing unit is used to determine the main provenance direction of the target layer during its deposition period; The fourth processing unit is used to cut a seismic profile through the well along the main source direction in the 3D seismic work area; a fifth processing unit, for inputting the top and bottom interfaces of the target layer in the seismic profile; a sixth processing unit for calculating the stratigraphic volume of the seismic section with the top and bottom interfaces as constraints; The seventh processing unit is used to observe the fluctuation of the stratigraphic body, find the second maximum amplitude point and the second depth value of the stratigraphic body in the upstream direction of the main source, and set the second depth value as the maximum lake flooding depth identified by the Wheeler domain profile; an eighth processing unit, configured to draw a perpendicular line on the seismic profile through the wellhead, wherein the length of the perpendicular line is equal to the width of the seismic profile, project the first maximum amplitude point and the second maximum amplitude point onto the perpendicular line, and set the third maximum amplitude point as the maximum lake flooding depth point determined on the seismic profile; The ninth processing unit is used to find the third maximum amplitude point according to the depth value of the third maximum amplitude point on the vertical line, and to track the seismic phase axis on the seismic profile with the third maximum amplitude point as the starting point. The obtained interface is the maximum lake flooding surface of a certain target layer segment on the seismic profile.

9. A computer-readable storage medium having a computer program stored thereon, characterized in that: When the computer program is executed by a processor, the steps of the method for identifying the maximum lake flooding surface based on earthquakes according to any one of claims 1 to 7 are implemented.

10. A computer device comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein: When the processor executes the computer program, the steps of the method for identifying the maximum lake flooding surface based on earthquakes according to any one of claims 1 to 7 are implemented.

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