Method for solving two-dimensional survey line static correction problem by utilizing three-dimensional surface survey dots

Abstract

A method for solving a two-dimensional survey line static correction problem by using three-dimensional surface survey points belongs to the technical field of seismic data processing near-surface static correction, firstly adopts three-dimensional surface survey points in a work area range to establish a field near-surface model, and calculates a two-dimensional static correction value through establishment of a three-dimensional model. And meanwhile, the inversion of the two-dimensional chromatography model is restrained through three-dimensional micro-logging and small refraction, so that the calculated chromatography static correction value is higher in precision, and a good effect is also achieved for the two-dimensional closing problem of multiple measuring lines. The method is designed by combining actual seismic data and a seismic work area, the steps are simple, the operation is easy, the final function can be quickly realized only by utilizing the existing method, a large amount of funds and personnel are saved, and most importantly, the processing period is shortened, and the efficiency of the static correction link can be doubled.

Description

Technical Field

[0001] The invention belongs to the technical field of near-surface static correction in seismic data processing, and in particular relates to a method for solving the static correction problem of a two-dimensional survey line by utilizing three-dimensional surface survey points. Background Art

[0002] Static correction is an important link to ensure the accuracy of seismic data processing and is one of the most important problems to be solved in seismic data processing. Static correction errors not only affect the signal-to-noise ratio of the data, but also affect the data resolution because the data cannot be stacked in phase. In order to improve the accuracy of velocity picking, a comprehensive application of velocity spectrum, dynamic correction gathers, variable velocity stacking profiles, etc. is adopted to obtain accurate stacking velocity. As the saying goes, "Solving the static correction problem is equivalent to solving almost half of the problems in seismic exploration." This sentence is enough to illustrate the status of static correction in seismic exploration. If the static correction problem is not solved well, it will be difficult to image the reflection waves on the horizontal stack, which is easy to cause structural morphological errors and affect structural interpretation. Furthermore, the accuracy of static correction also affects the signal-to-noise ratio of seismic data, and even affects the resolution of the data, which will cause errors in reservoir description and attribute analysis. At the same time, if the static correction problem is not solved well, it will also affect the imaging effect of pre-stack depth migration.

[0003] Old seismic data have more or less various problems, among which the most important one is the near-surface static correction problem. Since the data was collected in the early years, a lot of information is not fully preserved. How to make good use of the existing data to reprocess and achieve good results has become a top priority. The biggest impact is how to solve the static correction problem. Due to the lack of information, the commonly used static correction calculation method is not accurate and easily causes false structures. This brings great difficulties to the later interpretation work. Therefore, an accurate and efficient static correction calculation method is urgently needed to solve the static correction problem. Summary of the invention

[0004] In order to solve the above problems, the present invention proposes: a method for solving the static correction problem of a two-dimensional survey line by using three-dimensional surface survey points, comprising the following steps:

[0005] S1. First, you need to collect the electronic sps files of all 2D survey line grids, obtain the distribution range of the 2D survey lines, as well as the elevation and well depth, and collect the 3D surface survey point files involved in the work area;

[0006] S2. Load the 2D electronic sps file of the whole area and the 3D surface survey point file involved in the work area through the near-surface acquisition and processing system;

[0007] S3. Use the three-dimensional surface survey point file to build a near-surface structure model, interpret micro-well logging or small refraction curves, do a good job of stratification, and then smooth it to make the structure model more reasonable;

[0008] S4. Use the 3D model to calculate the static correction of the whole area, and then use the sps file of the 2D survey line to reflect it in the actual 2D survey line;

[0009] S5. Separate the high and low frequencies of the two-dimensional line static correction values ​​as needed, and output the required low-frequency value text;

[0010] S6, establishing an initial model by picking the first arrival of the two-dimensional line;

[0011] S7, loading the three-dimensional surface survey point data to perform constrained tomography inversion iteration on the initial model to ensure that the error values ​​of picking the first arrival and inverting the first arrival converge to a reasonable threshold value;

[0012] S8. Determine the high-speed layer top, calculate the tomographic static correction, and finally separate the tomographic amount into high and low frequencies, and output the final high-frequency component static correction text file.

[0013] Furthermore, in step S1, all three-dimensional survey points within the two-dimensional survey line are collected to ensure the accuracy of the three-dimensional model.

[0014] Furthermore, in step S2, the two-dimensional sps file and the three-dimensional survey point file are ensured to be accurate during the loading process.

[0015] Furthermore, in step S3, the three-dimensional survey point file is interpreted to ensure the rationality of the model.

[0016] Furthermore, before the step S4, it is necessary to ensure that the accuracy of the three-dimensional model meets the requirements. In the step S4, the static correction amount in the three-dimensional range is first calculated and then reflected and applied to the two-dimensional survey line.

[0017] Furthermore, in step S5, the calculated two-dimensional field static correction amount is separated into high and low frequencies, and the low frequency amount is output.

[0018] Furthermore, in step S6, the first arrival of the two-dimensional line is picked.

[0019] Furthermore, in step S7, the three-dimensional surface survey points are used to constrain the two-dimensional line tomography inversion.

[0020] Furthermore, in step S8, tomographic static correction calculation is performed, and then high-frequency components are extracted and output.

[0021] The beneficial effects of the present invention are as follows: the present invention is designed in combination with actual seismic data and seismic work areas, and is implemented together with near-surface model software and static correction software. The steps are relatively simple and easy to operate. The final function can be quickly realized by simply making good use of the existing software. A large amount of money and personnel can be saved, and the most important thing is to shorten the processing cycle, which can double the efficiency of the static correction link. The reprocessing of a large number of two-dimensional lines in the old area of ​​Jilin Oilfield has an immeasurable positive effect. The method is highly practical and has a wide range of applications. It can produce significant economic and social benefits in terms of reducing costs and increasing efficiency, or have a significant impact on the field of strategic advance reserve technology. It is expected to be transformed and create benefits within 1 year. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 Shown is a two-dimensional survey line distribution range diagram in an example of the present invention;

[0023] Figure 2 Shown is a distribution position diagram of three-dimensional surface survey points in a two-dimensional survey line grid in an example of the present invention;

[0024] Figure 3 Shown is a two-dimensional low-frequency component static correction plane distribution diagram calculated in an example of the present invention;

[0025] Figure 4 Shown is a near-surface structure model diagram inverted using three-dimensional micro-well logging and small refraction constraints in an example of the present invention;

[0026] Figure 5 Shown is a two-dimensional high-frequency component static correction plane distribution diagram calculated in an example of the present invention.

[0027] Figure 6 Shown are superimposed cross-sectional renderings before and after static correction is applied in an example of the present invention. DETAILED DESCRIPTION

[0028] In order to make the technical means and objectives of the present invention easy to understand, the present invention is further described below in combination with specific implementation methods. A method for solving the static correction problem of a two-dimensional survey line by using three-dimensional surface survey points includes the following steps:

[0029] S1. First, you need to collect the electronic sps files of all 2D survey line grids, obtain the distribution range of the 2D survey lines, as well as the elevation and well depth, and collect the 3D surface survey point files involved in the work area;

[0030] S2. Load the 2D electronic sps file of the whole area and the 3D surface survey point file involved in the work area through the near-surface acquisition and processing system;

[0031] S3. Use the three-dimensional surface survey point file to build a near-surface structure model, interpret micro-well logging or small refraction curves, do a good job of stratification, and then smooth it to make the structure model more reasonable;

[0032] S4. Use the 3D model to calculate the static correction of the whole area, and then use the sps file of the 2D survey line to reflect it in the actual 2D survey line;

[0033] S5. Separate the high and low frequencies of the two-dimensional line static correction values ​​as needed, and output the required low-frequency value text;

[0034] S6, establishing an initial model by picking the first arrival of the two-dimensional line;

[0035] S7, loading the three-dimensional surface survey point data to perform constrained tomography inversion iteration on the initial model to ensure that the error values ​​of picking the first arrival and inverting the first arrival converge to a reasonable threshold value;

[0036] S8. Determine the high-speed layer top, calculate the tomographic static correction, and finally separate the tomographic amount into high and low frequencies, and output the final high-frequency component static correction text file.

[0037] Reference Figure 1 , Step 1: Load sps files and data preparation of table files

[0038] This invention uses 148 two-dimensional line data of the western slope from 1988 to 2005 as an example;

[0039] The main requirements are standard sps file format and standard loadable surface files. Due to data collection, some survey lines need to convert electronic shift reports to sps files. At the same time, all sps files must be QC controlled to ensure data availability.

[0040] Step 2: If Figure 2 As shown, fully load all 2D line sps files and 3D surface survey point files within the scope involved, ensure that there are no errors in the loading process, and perform quality control through plane monitoring. The problematic data needs to be modified.

[0041] Step 3: If Figure 3 As shown in the figure, using the three-dimensional surface survey points, the static correction value within the work area is first calculated, and then the high and low frequencies are separated to output the static correction low-frequency component of the two-dimensional survey line. This quantity has a certain mirror relationship with the surface elevation.

[0042] Step 4: Figure 4 As shown in the figure, the initial model is constrained by three-dimensional micro-logging and small refraction points when calculating the high-frequency quantity of the tomography to ensure the accuracy of the inversion model. It can be seen that the velocity of the low-speed drop zone is more accurate. It is conducive to defining the high-speed layer top interface.

[0043] Step 5: The tomographic statics are then calculated by replacing the velocity and the final reference plane and combining the refraction residual, and its high-frequency components are extracted, such as Figure 5 shown.

[0044] Step 6: Combine the low-frequency component and the high-frequency component in the final application to achieve the purpose of solving the static correction problem and ensure the closure of the subsequent two-dimensional survey line. Figure 6 shown.

[0045] The above-established method of using three-dimensional surface survey points to solve the static correction problem of two-dimensional survey lines is the first to establish a field near-surface model by using three-dimensional surface survey points within the work area. The two-dimensional static correction is calculated by establishing a three-dimensional model, which solves the problem that the static correction problem caused by the early construction of the two-dimensional survey line and the lack of collection information cannot be solved well. At the same time, the two-dimensional tomographic model inversion is constrained by three-dimensional micro-well logging and small refraction, so that the calculated tomographic static correction is more accurate. It also achieves good results for the two-dimensional closure problem of multiple survey lines. The method is designed in combination with actual seismic data and seismic work areas. Relatively speaking, the steps are simple and easy to operate. Only by making good use of the existing methods can the final function be quickly realized. It saves a lot of money and personnel, and most importantly, shortens the processing cycle, which can double the efficiency of the static correction link. It has an immeasurable positive effect on the reprocessing of a large number of old two-dimensional lines in Jilin Oilfield. This method is highly practical and has a wide range of applications. It can produce significant economic and social benefits in terms of cost reduction and efficiency improvement, or have a significant impact on the field of strategic advanced reserve technology. It is expected to be transformed and effective within 1 year.

[0046] The device embodiments described above are merely illustrative, wherein the units described as separate components may or may not be physically separated, and the components displayed as units may or may not be physical units, that is, they may be located in one place, or they may be distributed on multiple network units. Some or all of the modules may be selected according to actual needs to achieve the purpose of the scheme of this embodiment. Ordinary technicians in this field can understand and implement it without paying creative labor.

[0047] Through the description of the above implementation methods, those skilled in the art can clearly understand that each implementation method can be implemented by means of software plus a necessary general hardware platform, and of course, by hardware. Based on this understanding, the above technical solution can be essentially or in other words, the part that contributes to the relevant technology can be embodied in the form of a software product, which can be stored in a computer-readable storage medium, such as ROM / RAM, a disk, an optical disk, etc., including a number of instructions for a computer device (which can be a personal computer, a server, or a network device, etc.) to execute the methods described in each embodiment or some parts of the embodiment.

[0048] To solve the static correction problem, we need to do well in two aspects.

[0049] First, the short-wavelength static correction is calculated; usually caused by drastic changes in the near surface, affecting the superposition effect. Usually, the first arrival tomography inversion method is needed to solve it.

[0050] The second is to calculate the long-wavelength static correction; it is caused by the near-surface gradual change, and its impact is mainly reflected in the structural morphology, and it has little effect on the superposition effect. Usually, the long-wavelength problem is solved through field micro-logging and small refraction.

[0051] The above description is only a preferred specific implementation manner of the present invention, but the protection scope of the present invention is not limited thereto. Any technician familiar with the technical field can make equivalent replacements or changes according to the technical solutions and concepts of the present invention within the technical scope disclosed by the present invention, which should be covered by the protection scope of the present invention.

Claims

1. A method for solving the static correction problem of a two-dimensional survey line using three-dimensional surface survey points, characterized in that: The following steps are involved: S1. First, you need to collect the electronic sps files of all 2D survey line grids, obtain the distribution range of the 2D survey lines, as well as the elevation and well depth, and collect the 3D surface survey point files involved in the work area; S2. Load the 2D electronic sps file of the whole area and the 3D surface survey point file involved in the work area through the near-surface acquisition and processing system; S3. Use the three-dimensional surface survey point file to build a near-surface structure model, interpret micro-well logging or small refraction curves, do a good job of stratification, and then smooth it to make the structure model more reasonable; S4. Use the 3D model to calculate the static correction of the whole area, and then use the sps file of the 2D survey line to reflect it in the actual 2D survey line; S5. Separate the high and low frequencies of the two-dimensional line static correction values ​​as needed, and output the required low-frequency value text; S6, establishing an initial model by picking the first arrival of the two-dimensional line; S7, loading the three-dimensional surface survey point data to perform constrained tomography inversion iteration on the initial model to ensure that the error values ​​of picking the first arrival and inverting the first arrival converge to a reasonable threshold value; S8. Determine the high-speed layer top, calculate the tomographic static correction, and finally separate the tomographic amount into high and low frequencies, and output the final high-frequency component static correction text file.

2. The method for solving the static correction problem of two-dimensional survey lines by using three-dimensional surface survey points as claimed in claim 1, characterized in that: In the step S1, all three-dimensional survey points within the two-dimensional survey line are collected to ensure the accuracy of the three-dimensional model.

3. The method for solving the static correction problem of two-dimensional survey lines by using three-dimensional surface survey points as claimed in claim 1, characterized in that: In step S2, the two-dimensional sps file and the three-dimensional survey point file are ensured to be accurate during the loading process.

4. The method for solving the static correction problem of two-dimensional survey lines by using three-dimensional surface survey points as claimed in claim 1, characterized in that: In step S3, the three-dimensional survey point file is interpreted to ensure the rationality of the model.

5. The method for solving the static correction problem of two-dimensional survey lines by using three-dimensional surface survey points as claimed in claim 1, characterized in that: Before the step S4, it is necessary to ensure that the accuracy of the three-dimensional model meets the requirements. In the step S4, the static correction amount in the three-dimensional range is first calculated and then reflected and applied to the two-dimensional survey line.

6. The method for solving the static correction problem of two-dimensional survey lines by using three-dimensional surface survey points as claimed in claim 1, characterized in that: In step S5, the calculated two-dimensional field static correction amount is separated into high and low frequencies, and the low frequency amount is output.

7. The method for solving the static correction problem of two-dimensional survey lines by using three-dimensional surface survey points as claimed in claim 1, characterized in that: In the step S6, the first arrival of the two-dimensional line is picked.

8. The method for solving the static correction problem of two-dimensional survey lines by using three-dimensional surface survey points as claimed in claim 1, characterized in that: In step S7, the three-dimensional surface survey points are used to constrain the two-dimensional line tomography inversion.

9. The method for solving the static correction problem of two-dimensional survey lines by using three-dimensional surface survey points as claimed in claim 1, characterized in that: In step S8, tomographic static correction calculation is performed, and then high-frequency components are extracted and output.

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