Three-dimensional seismic acquisition control supplemental shot constraint method
By calculating the density distribution ratio of unsuccessfully detonated blast points, it is possible to accurately determine whether additional blasting is needed, thus solving the problem of high construction costs in existing technologies and improving construction efficiency and quality.
Patent Information
- Application Number
- CN202310040290.1
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- Filing Date
- 2023-01-11
- Publication Date
- 2026-08-04
- Estimated Expiration
- 2043-01-11
AI Technical Summary
Existing technology cannot accurately determine the impact of not performing additional blasting on construction quality, resulting in high construction costs.
By calculating the ratio of the number of effective firing points to the theoretical number of firing points within the influence range of unsuccessfully detonated firing points, it can be determined whether additional firing is needed.
It improved the construction process, reduced construction costs, and ensured construction quality.
Smart Images
Figure CN115963560B_ABST
Abstract
Description
Technical Field
[0001] This invention relates to a method for controlling supplementary shots in three-dimensional seismic acquisition, belonging to the field of three-dimensional seismic exploration technology. Background Technology
[0002] As domestic oil and gas exploration deepens, the surface conditions in 3D seismic exploration are becoming increasingly complex, especially in seismic acquisition in villages and urban areas, where obstacles such as buildings, roads, bridges, and rivers are scattered throughout. Current seismic acquisition operations employ high-density, high-coverage firing rates, typically exceeding 200 firings. To overcome the adverse effects of these obstacles on the coverage rate, in addition to meeting the coverage requirements, more design shot points or increased shot arrangement are generally used to ensure construction quality. During the design process, the coverage rate usually exceeds the design range. However, due to the issue of empty shot sections, the density of shot points in the area becomes uneven. Often, every shot in a low-density shot point area is crucial; any missing shot will result in a significant empty shot section. To ensure construction quality, it is necessary to ensure that all shot points in low-density shot point areas can be normally fired to meet the design requirements for the coverage rate and obtain good seismic records and profiles.
[0003] During construction, various factors may cause some shot points to fail to detonate or become unusable, affecting the quality of the design and necessitating replacement shots. This forces the seismic team to temporarily halt construction, especially in mountainous seismic exploration where replacing a well can be time-consuming. However, considering the overall construction quality, a reliable statistical evaluation method is needed to determine whether the lack of these shot points affects the overall quality of the seismic acquisition process and whether replacement shots are necessary. This statistical evaluation method aims to achieve both high-efficiency acquisition without compromising construction quality. Existing technologies, such as Chinese patent application CN113156508A, disclose a method and system for determining the effective coverage times of a well shot observation system. This method determines the target layer signal-to-noise ratio (SNR) of each type of source point based on the effective coverage times of a single shot, then determines the effective coverage times of each type of source point for each area based on the target layer SNR, and finally accurately determines the coverage times of all areas in the work zone based on the effective coverage times of each type of source point for each area. This method evaluates whether the observation system can complete the geological task. Chinese patent application CN105487106A discloses a method for supplementary blasting based on Gaussian ray beam target layer energy illumination. It establishes a three-dimensional geological model of the exploration area based on existing geological data, performs illumination analysis on the geological model using Gaussian ray beams from the blast points to determine the target layer element offset energy, statistically analyzes the target layer element offset energy distribution to delineate energy-weak areas within the target layer, and determines the corresponding surface supplementary blasting areas based on the illumination reference values of each blast point for these energy-weak areas. Supplementary blasting points are then set at equal intervals within the existing blasting point grid in the surface supplementary blasting area. However, it lacks a corresponding method for determining whether supplementary blasting is necessary during construction.
[0004] Therefore, existing technologies generally judge based on the number of times the blasting is applied, which makes it difficult to accurately understand the impact of not applying the blasting on the construction quality. In order to ensure quality, all the blasting is applied, resulting in higher costs. Summary of the Invention
[0005] The purpose of this invention is to provide a three-dimensional seismic acquisition control supplementary shot constraint method to solve the problem of high construction costs caused by the inability to accurately describe the impact of not supplementing shots.
[0006] To solve the above-mentioned technical problems, this invention provides a three-dimensional seismic acquisition control supplementary shot constraint method, which includes the following steps:
[0007] 1) Calculate the shot density according to the design requirements of the work area observation system;
[0008] 2) Based on the requirement of the shallowest target layer depth, the shallowest target layer depth is used as the radius of the maximum statistical circle, and the theoretical number of shot points within the statistical circle is calculated based on the shot point density.
[0009] 3) Locate the undetonated blast points, determine the influence range of the blast point with the location of the blast point as the center and the shallowest target layer depth as the radius, and count the number of effective blast points within this range;
[0010] 4) Calculate the density distribution ratio of the undetonated shot points based on the theoretical number of shot points and the effective number of shot points;
[0011] 5) Determine whether a shot needs to be fired again based on the shot density distribution ratio of the shot point.
[0012] This invention identifies undetonated shot points, determines their influence range, and counts the number of effective shot points within that range. Using the theoretical number of shot points within the statistical circle, it calculates the shot point density distribution ratio of the undetonated shot point to determine whether supplementary shot is needed. Therefore, this invention, through effective shot point density control, can improve the construction process, reduce construction costs, and better guide seismic acquisition construction while ensuring that shallow data meets requirements.
[0013] Furthermore, the formula for calculating the theoretical number of shot points in step 2) is:
[0014] P=πρd 2 / 1000000
[0015] P represents the theoretical number of shot points; d represents the shallowest target layer depth in meters; ρ represents the shot point density in square kilometers.
[0016] This invention calculates the theoretical number of shot points based on the shallowest target layer depth required by the design and the required shot point density, which can accurately calculate the theoretical number of shot points and provide an accurate basis for subsequent calculations.
[0017] Furthermore, the calculation formula for the aforementioned shot point density distribution ratio is as follows:
[0018] B ij =A ij / P
[0019] B ij A represents the density distribution ratio of undetonated shot points corresponding to grid numbers i and j. ij For B ij The number of effective shot points within the statistical circle, where P is the theoretical number of shot points.
[0020] This invention calculates the density distribution ratio of undetonated blast points based on the number of effective blast points and the theoretical number of blast points within the influence range of the undetonated blast points. This density distribution ratio can accurately describe the impact of whether or not a high-explosive blast point is supplemented.
[0021] Furthermore, the judgment criteria in step 5) are as follows:
[0022] If B ij ≥1 indicates that the blasting point has little impact on the construction quality and no additional blasting is required.
[0023] If 80% ij <1, further consultation and judgment are needed;
[0024] If 80% > B ij We must fire a follow-up shot.
[0025] This invention determines whether to fire a follow-up shot by analyzing the range of the shot density distribution ratio, thereby improving the accuracy of follow-up shot determination.
[0026] Furthermore, in step 3), the statistics of effective firing points are completed by determining whether the effective firing points are within the influence range of the firing points that were not successfully detonated. Attached Figure Description
[0027] Figure 1 This is a flowchart of the three-dimensional seismic acquisition control supplementary shot constraint method of the present invention;
[0028] Figure 2 A statistical diagram illustrating the effective firing points of this invention. Detailed Implementation
[0029] The specific embodiments of the present invention will be further described below with reference to the accompanying drawings.
[0030] This invention first calculates the shot density based on the design requirements of the work area observation system; then, based on the shallowest target layer depth requirement, using the shallowest target layer depth as the maximum statistical circle radius, it calculates the theoretical number of shot points within the statistical circle based on the shot density; next, it identifies undetonated shot points, determines the influence range of these shot points with their location as the center and the shallowest target layer depth as the radius, and counts the effective shot points within this range; finally, it calculates the shot density distribution ratio of the undetonated shot points based on the theoretical and effective shot point counts, and determines whether the shot point needs to be re-fired based on this ratio. The following example from a domestic work area further illustrates the specific implementation process of this invention. Figure 1 As shown, firstly, the observation system data is read, and the shot density ρ is calculated. The required maximum statistical circular area radius d meters is obtained from the shallowest target layer depth d, and the design shot number P within the circular area is calculated. The work area is gridded, and the number of shot points corresponding to each grid is calculated. This number is divided by P to obtain the shot density distribution ratio. For each abnormal shot point, the need for supplementary blasting is quickly determined by comparing its corresponding grid ratio, thus accelerating the construction process. The specific steps are as follows:
[0031] 1. Based on the design of the work area observation system, calculate the design shot point density, i.e., the number of shot points ρ per square kilometer.
[0032] In this embodiment, the design of the work area observation system requires a shot line distance of 300 meters and a shot point distance of 50 meters. Based on this, the shot point density is calculated as follows: the number of shot points per square kilometer ρ = 1000 * 1000 / (300 * 50) = 66.7.
[0033] 2. Obtain the required maximum statistical circular radius d meters from the shallowest target depth d, and calculate the number of shot points P = πρd in the direction of the line number and point number for this segment. 2 / 1000000.
[0034] In this embodiment, the minimum depth required by Party A is d = 600 meters. Based on the density calculated in step 1, the number of shot points in the direction of the line number and point number for this segment is calculated as follows:
[0035] P=πρd 2 / 1000000=75.4.
[0036] 3. Observe the system data to obtain receiver points (RLNO, RINO) and shot points (SLNO, SINO) based on the shot point element numbers. The increment is equal to the element size (Bin) in the X and Y coordinate directions of the receiver point number grid. X and Bin Y .
[0037] Based on the data from the observation system in this embodiment, the receiver line number RLNO and receiver line number increment ΔRL=2, receiver point number RINO, shot line number SLNO, shot point number SINO, and grid cell size Bin in the X and Y coordinate directions are obtained. X =12.5m and Bin Y =12.5m.
[0038] 4. Calculate the number of effective shot points that have been completed within the circular region of radius d.
[0039] 4.1 Define the array A of shot counts ij All data elements are initialized to zero.
[0040] i min =j min =0, i max =RINO max -RINO min j max =RLNO max -RLNO min ;
[0041] Where i and j are natural ordinal numbers, RINO min and RINO max The minimum and maximum receiver point numbers are specified in this embodiment. The minimum receiver point number is 1145, and the maximum receiver point number is 3089. (RLNO) minand RLNO max The minimum received line number is 1001 and the maximum received line number is 2092. In this embodiment, the minimum received line number is 1001 and the maximum received line number is 2092.
[0042] 4.2 Count the number of shot points within the circular area with radius d.
[0043] (1) For the number of shot points in the first shot point grid (i, j), where i = 0, j = 0, assume its corresponding coordinates (X0, Y0).
[0044] Search all the effective shot points (SLNO, SINO) that have been completed. For any shot point coordinates (X, Y), if D = ((X0 - X) * (X0 - X) + (Y0 - Y) * (Y0 - Y))^1 / 2 < d, the number of shot points A ij is incremented by 1. This shot point is within the maximum statistical circle inner diameter of the first shot point grid, as Figure 2 shown.
[0045] (2) Calculate the number of shot points in the next shot point grid (i, j), where i = i, j = j + 1. Corresponding coordinates (X0, Y0), search all the effective shot points (SLNO, SINO) that have been completed. For any shot point coordinates (X, Y), if D = ((X0 - X) * (X0 - X) + (Y0 - Y) * (Y0 - Y))^1 / 2 < d, the number of shot points A ij is incremented by 1.
[0046] (3) For the number of shot points in the next shot point grid (i, j), where i = i, j = j + 1, repeat the operation in step (2) to complete the calculation of the number of window shot points corresponding to all the effective shot points on the first grid line.
[0047] (4) For the number of shot points in the first shot point grid (i, j) of the next line, where i = i + 1, j = 0. Corresponding coordinates (X0, Y0):
[0048] Search all the effective shot points (SLNO, SINO) that have been completed. For any shot point coordinates (X, Y), if D = ((X0 - X) * (X0 - X) + (Y0 - Y) * (Y0 - Y))^1 / 2 < d, the number of shot points A ij is incremented by 1.
[0049] (5) Calculate the number of shot points in the next shot point grid (i, j), where i = i, j = j + 1. Corresponding coordinates (X0, Y0), search all the effective shot points (SLNO, SINO) that have been completed. For any shot point coordinates (X, Y), if D = ((X0 - X) * (X0 - X) + (Y0 - Y) * (Y0 - Y))^1 / 2 < d, the number of shot points A ij is incremented by 1.
[0050] (6) For the number of shot points in the next shot point grid (i, j), i = i, j = j + 1, repeat step (5) to complete the calculation of the number of shot points in the window corresponding to all the completed valid shot points of this grid line.
[0051] (7) Repeat (4)-(6) to complete the calculation of the number of window shot points corresponding to all grid lines and effective shot points.
[0052] 5. Calculate the shot density distribution ratio based on the number of effective shot points completed within the circular region of radius d. The formula used to calculate the shot density distribution ratio is:
[0053] B ij =A ij / P
[0054] 6. For the locations of shot points that failed to detonate, calculate the shot point density distribution ratio B corresponding to their grid numbers m and n. mn The need for additional shots is determined based on the calculated density distribution ratio of the shot points.
[0055] If B mn If the value is ≥1, the impact of this blasting point on the construction quality is minor and can be ignored; no additional blasting is required.
[0056] If 80% mn <1. Discuss and resolve the issue with Party A.
[0057] If 80% > B mn We must fire a follow-up shot.
[0058] This embodiment uses 1 and 80% as the boundary. In other implementation methods, other values can be used as the boundary according to the actual situation.
[0059] This method can estimate whether abnormal detonation points need to be supplemented by using completed qualified blasting points (effective blasting points), thereby reducing the number of supplementary blasts and improving the construction progress. In this embodiment, it can reduce blasting time by more than 5% and save up to 1 million yuan in costs per construction period.
Claims
1. A method for controlling supplementary shots in three-dimensional seismic acquisition, characterized in that, The method includes the following steps: 1) Calculate the shot density according to the design requirements of the work area observation system; 2) Based on the requirement of the shallowest target layer depth, the shallowest target layer depth is used as the radius of the maximum statistical circle, and the theoretical number of shot points within the statistical circle is calculated based on the shot point density. 3) Locate the undetonated blast points, determine the influence range of the blast point with the location of the blast point as the center and the shallowest target layer depth as the radius, and count the number of effective blast points within this range; 4) Calculate the density distribution ratio of the undetonated shot points based on the theoretical number of shot points and the effective number of shot points; 5) Determine whether a shot needs to be fired again based on the shot density distribution ratio of the shot point.
2. The three-dimensional seismic acquisition control supplementary shot constraint method according to claim 1, characterized in that, The formula for calculating the theoretical number of shot points in step 2) is: P=πρd 2 / 1000000 P represents the theoretical number of shot points; d represents the shallowest target layer depth in meters; ρ represents the shot point density in square kilometers.
3. The three-dimensional seismic acquisition control supplementary shot constraint method according to claim 1 or 2, characterized in that, The formula used to calculate the shot point density distribution ratio is as follows: B ij =A ij / P B ij A represents the density distribution ratio of undetonated shot points corresponding to grid numbers i and j. ij For B ij The number of effective shot points within the statistical circle, where P is the theoretical number of shot points.
4. The three-dimensional seismic acquisition control supplementary shot constraint method according to claim 3, characterized in that, The judgment criteria in step 5) are as follows: If B ij ≥1 indicates that the blasting point has little impact on the construction quality and no additional blasting is required. If 80% ij <1, further consultation and judgment are needed; If 80% > B ij We must fire a follow-up shot.
5. The three-dimensional seismic acquisition control supplementary shot constraint method according to claim 1, characterized in that, In step 3), the statistics of effective firing points are completed by determining whether the effective firing points are within the influence range of the firing points that were not successfully detonated.