Prestack energy consistency processing method for full-node seismic data

Abstract

The present invention provides a full-node seismic data pre-stack energy consistency processing method, which includes: step 1, loading an observation system and a processing grid; step 2, calculating the number of coverages within a bin; step 3, calculating a normalization factor for the number of coverages; step 4, determining a partitioning region; step 5, performing regional partitioning; step 6, obtaining a regional energy proportional factor; step 7, obtaining a seismic trace energy compensation factor; and step 8, applying the seismic energy compensation factor. The full-node seismic data pre-stack energy consistency processing method comprehensively considers the pre-stack energy consistency of seismic data from the perspectives of coverage times and regions, and has more reasonable results and higher accuracy than conventional methods. It is developed for full-node acquired seismic data, adapts to ultra-large acquisition arrays, and is also applicable to traditional non-full-node acquired seismic data. The operation is simple and easy to implement.

Description

Technical Field

[0001] The present invention relates to the technical field of oil and gas exploration seismic data processing, and in particular to a full-node seismic data pre-stack energy consistency processing method. Background Art

[0002] The existing pre-stack energy consistency methods for seismic data mainly include the spherical diffusion compensation method and the surface consistency amplitude compensation method. These methods are suitable for seismic data collected based on traditional observation systems. In the actual application of pre-stack energy consistency processing of full-node seismic data, these energy compensation methods have certain limitations. The compensation error of the spherical diffusion compensation method will increase with the increase of the compensation radius. The surface consistency amplitude compensation method cannot achieve satisfactory results in the full-node acquisition of distant source arrangements. These methods cannot be applied to the energy differences generated by the acquisition of seismic data by full-node ultra-large observation system arrangements. There is currently no energy compensation method for full-node acquisition of seismic data.

[0003] Chinese patent application number CN201110265103.7 discloses a method for surface-consistent energy compensation using vertical seismic profile data in seismic exploration data processing. The method applies noise suppression and spherical diffusion compensation to downhole three-component vertical seismic profile data. The starting point of the neutron wave in the seismic data is picked as the first arrival. A time window is created in the vertical component, extending backward from the first arrival. The square sum of each sample point in the three components within this time window is calculated, and the square root of the square sum is taken as the first arrival energy of the downlink wave of the signal. Each compensated sample point is then divided by the first arrival energy of the downlink wave. This process is repeated until surface-consistent energy compensation is completed for all seismic traces. This invention primarily utilizes the first arrival energy of the downlink wave in the original wavefield to compensate for the consistency of excitation and transmission energies. It offers high fidelity, simplicity, and computational efficiency.

[0004] Chinese patent application number CN201210536609.1 discloses a method for processing seismic data for geophysical exploration, specifically a velocity splicing method for contiguous processing of two-dimensional seismic data. This velocity file splicing method includes seismic data acquisition, pre-stack preprocessing of each block of seismic data, velocity analysis of the seismic data blocks, and velocity file splicing. The spliced ​​velocity files can then be used for dynamic correction, stacking, and post-stack migration of contiguous two-dimensional seismic data from different work areas. This method enables contiguous splicing of two-dimensional velocity data based on parameters such as the splicing spatial position of different seismic data, the CMP distances before and after bin averaging, and the CMP numbers corresponding to the splicing points. Post-stack migration of the spliced ​​seismic data can be performed using the spliced ​​velocity files and the aforementioned seismic data as input. This technology can significantly shorten the processing cycle for 2D seismic data splicing and provides technical support for a comprehensive understanding of underground macrostructures and exploration deployment.

[0005] The Chinese patent application with application number CN201110183404.5 relates to a method for processing multi-component seismic data, belonging to the field of geophysical exploration data processing. The method employs first-arrival intelligent picking and tomographic static correction technology to perform a static correction on the multi-component seismic data. Pre-stack seismic data that clearly reflects the characteristics of structural and lithologic changes is then obtained through pre-stack denoising, high-fidelity processing, and deconvolution. The corresponding relationship between P-waves and converted waves is then used to obtain an accurate velocity field, and the pre-stack seismic data is stacked to obtain a stacked profile of the multi-component seismic data. Finally, the FX domain wave equation finite-difference migration technique is employed to improve the lateral resolution and obtain a migrated profile of the multi-component seismic data. This invention allows the use of general P-wave software to process converted wave seismic data, resulting in a high-resolution, high-fidelity, high-signal-to-noise ratio seismic profile that clearly reflects the characteristics of structural and lithologic changes.

[0006] The above existing technologies are significantly different from the present invention and fail to solve the technical problem we want to solve. Therefore, we have invented a new full-node seismic data pre-stack energy consistency processing method. Summary of the Invention

[0007] The purpose of the present invention is to provide a full-node seismic data pre-stack energy consistency processing method for obtaining a full-node seismic data pre-stack energy compensation factor by combining coverage times with regional energy regularization.

[0008] The object of the present invention can be achieved by the following technical measures: a full-node seismic data pre-stack energy consistency processing method, the full-node seismic data pre-stack energy consistency processing method comprising:

[0009] Step 1: Load the observation system and processing grid;

[0010] Step 2, calculate the number of coverages within the bin;

[0011] Step 3, calculate the coverage normalization factor;

[0012] Step 4, determine the subdivision area;

[0013] Step 5, perform regional segmentation;

[0014] Step 6, calculate the regional energy scaling factor;

[0015] Step 7, obtaining the seismic trace energy compensation factor;

[0016] Step 8: Apply the earthquake energy compensation factor.

[0017] The purpose of the present invention can also be achieved by the following technical measures:

[0018] In step 1, the seismic data and survey results collected in the field are merged and loaded into the processing grid.

[0019] In step 2, after loading the observation system and processing grid, count the number of coverages within the bin:

[0020]

[0021] Among them, F is the number of coverage, R sn To arrange the number of single-line receiving channels, R sd is the track distance, R n is the number of receiving lines, R d is the receiving line distance, L s S is the least common multiple of the receiving track spacing and the gun row spacing, g It is the least common multiple of the shot point distance and the receiving line distance.

[0022] In step 3, the normalization factor of the coverage of the seismic trace is the inverse of the coverage of the bin in which it is located:

[0023]

[0024] Among them, N i is the normalization factor of the ith channel, and F is the number of times the bin of the ith channel is covered.

[0025] In step 4, based on the seismic data header information after loading the observation system, the area range of the acquisition arrangement slice where the seismic trace is located is determined. For conventional seismic acquisition, this area is rectangular, but for full-node acquisition data, this area is affected by the node data cutting and is an asymmetric polygon.

[0026] In step 5, the actual coordinates of the seismic traces are used as points, and all adjacent points are connected. This will form triangles with adjacent seismic traces as vertices. The perpendicular bisectors of the sides of each triangle are drawn, so that each seismic trace is surrounded by a unique polygon.

[0027] In step 6, the energy value of each polygon is represented by the seismic traces it encloses, and the energy distribution in the entire area is calculated, and then the regional relative energy ratio factor of each seismic trace and the surrounding seismic traces is calculated.

[0028] In step 7, the normalization factor N obtained in the above steps is i and regional relative energy scaling factor M i Calculate the seismic trace energy compensation factor K i :

[0029] K i =aN i +bM i (Formula 3)

[0030] Among them, a i , b i is an empirical parameter.

[0031] In step 8, the obtained compensation factor is applied to the seismic trace to complete the pre-stack energy consistency processing of the full-node seismic data.

[0032] The full-node seismic data pre-stack energy consistency processing method in the present invention is a full-node seismic data pre-stack energy consistency processing method based on the combined application of coverage times and regional energy regularization. The main technical key points are the following three: ① Calculating the coverage times normalization factor; ② Obtaining the regional energy proportional factor; ③ Obtaining the seismic trace energy compensation factor.

[0033] This full-node seismic data pre-stack energy consistency processing method has advantages that other methods do not have. Its specific advantages and characteristics are reflected in the following aspects:

[0034] 1. Reliability of the method: This method comprehensively considers the pre-stack energy consistency of seismic data from the perspective of coverage times and regions, and its results are more reasonable and more accurate than those of conventional methods.

[0035] 2. The method is highly adaptable. This method was developed for seismic data collected by full nodes and is suitable for ultra-large acquisition arrays. It is also applicable to traditional seismic data collected by non-full nodes.

[0036] 3. Simple operation and easy implementation: The method has simple process and parameter settings and fast calculation speed. BRIEF DESCRIPTION OF THE DRAWINGS

[0037] Figure 1A schematic diagram of an OVT slice of seismic data without energy compensation in a specific embodiment of the present invention;

[0038] Figure 2 A schematic diagram of an OVT slice of seismic data after applying the method of the present invention in a specific embodiment of the present invention;

[0039] Figure 3 A schematic diagram of a stacked section of seismic data without energy compensation in a specific embodiment of the present invention;

[0040] Figure 4 A schematic diagram of a stacked section of seismic data after applying the method of the present invention in a specific embodiment of the present invention;

[0041] Figure 5 This is a flow chart of a specific embodiment of the method for processing pre-stack energy consistency of full-node seismic data of the present invention;

[0042] Figure 6 A schematic diagram of an OVT slice of seismic data without energy compensation in a specific embodiment of the present invention;

[0043] Figure 7 Schematic diagram of an OVT slice of seismic data after applying the method of the present invention in a specific embodiment of the present invention. DETAILED DESCRIPTION

[0044] It should be noted that the following detailed descriptions are exemplary and intended to provide further explanation of the present invention. Unless otherwise specified, all technical and scientific terms used herein have the same meaning as commonly understood by those skilled in the art to which the present invention belongs.

[0045] It should be noted that the terms used herein are only for describing specific embodiments and are not intended to limit the exemplary embodiments according to the present invention. As used herein, unless the context clearly indicates otherwise, the singular form is intended to include the plural form. In addition, it should be understood that when the terms "comprise" and / or "include" are used in this specification, they indicate the presence of features, steps, operations and / or combinations thereof.

[0046] If subsequent seismic data processing is performed on seismic data with energy differences, it will affect the energy consistency of the data, making the stacked profile energy uneven, and will also cause the offset profile to draw an arc, further affecting the resolution of the seismic data and the accuracy of the offset homing, and ultimately inevitably affecting the quality of the entire data processing. The full-node seismic data acquisition method is a new acquisition method. The acquisition arrangement slices of the full-node seismic data are large, and each acquisition arrangement slice involves a large area range and a high number of coverages, resulting in large differences in the pre-stack energy of the seismic data. Compared with traditional seismic data acquisition methods, the acquisition arrangement slices of the full-node seismic data are larger and the energy consistency is worse. Therefore, a targeted energy consistency processing method is needed. In order to solve the problem of pre-stack energy inconsistency of full-node seismic data, the present invention designs a full-node seismic data pre-stack energy consistency processing method that combines the number of coverages with regional energy regularization.

[0047] The coverage factor is the number of seismic traces within a bin. This can be calculated by loading the seismic data observation system and processing grid, and a normalization factor is calculated based on the coverage factor. The acquisition array to which the seismic data within the bin belongs can also be extracted from the seismic data observation system, thus determining the distribution area of ​​the array. Based on the location of the seismic traces, a Thiessen polygon is generated within the array distribution area to determine the relative energy scaling factor of each seismic trace within the area. The normalization factor and scaling factor are combined to calculate the seismic trace energy compensation factor. The compensation factor is applied to the seismic traces to complete the energy consistency processing.

[0048] The full-node seismic data pre-stack energy consistency processing method of the present invention comprises the following steps:

[0049] Step 1: Load the observation system and processing grid;

[0050] Step 2, calculate the number of coverages within the bin;

[0051] Step 3, calculate the coverage normalization factor;

[0052] Step 4, determine the subdivision area;

[0053] Step 5, perform regional segmentation;

[0054] Step 6, calculate the regional energy scaling factor;

[0055] Step 7, obtaining the seismic trace energy compensation factor;

[0056] Step 8: Apply the earthquake energy compensation factor.

[0057] The following are several specific embodiments of the present invention.

[0058] Example 1

[0059] like Figure 5 As shown, Figure 5 This is a flow chart of the full-node seismic data pre-stack energy consistency processing method of the present invention. The full-node seismic data pre-stack energy consistency processing method includes:

[0060] (1) Loading the observation system and processing grid. Merge the seismic data collected in the field and the measurement results, and load the processing grid.

[0061] (2) Calculate the number of coverages within a cell. After loading the observation system and processing grid, the number of coverages F within a cell can be calculated.

[0062]

[0063] Among them, F is the number of coverage, R sn To arrange the number of single-line receiving channels, R sd is the track distance, R n is the number of receiving lines, R d is the receiving line distance, L s S is the least common multiple of the receiving track spacing and the gun row spacing, g It is the least common multiple of the shot point distance and the receiving line distance.

[0064] (3) Calculate the coverage normalization factor. The coverage normalization factor of a seismic trace is the inverse of the coverage of the bin in which it is located.

[0065]

[0066] Among them, N i is the normalization factor of the ith channel, and F is the number of times the bin of the ith channel is covered.

[0067] (4) Determine the segmentation area. Based on the seismic data header information after loading the observation system, determine the area range of the acquisition array where the seismic trace is located. For conventional seismic acquisition, this area is generally rectangular, but for full-node acquisition data, this area is affected by the node data cutting and is mostly an asymmetric polygon.

[0068] (5) Regional division. Take the actual coordinates of the seismic traces as points and connect all adjacent points. This will form triangles with the adjacent seismic traces as vertices. Draw the perpendicular bisectors of the sides of each triangle. In this way, each seismic trace will be surrounded by a unique polygon.

[0069] (6) Obtain the regional energy scaling factor. The energy value of each polygon is represented by the seismic traces it encloses. The energy distribution in the entire region can be calculated, and then the regional relative energy scaling factor of each seismic trace and the surrounding seismic traces can be calculated.

[0070] (7) Obtain the seismic trace energy compensation factor. The normalization factor N obtained in the above steps is i and regional relative energy scaling factor M i Calculate the seismic trace energy compensation factor K i .

[0071] K i =aN i +bM i (Formula 3)

[0072] Among them, a i , b i is an empirical parameter.

[0073] (8) Application of seismic energy compensation factor: Apply the calculated compensation factor to the seismic trace to complete the pre-stack energy consistency processing of the full-node seismic data.

[0074] Example 2

[0075] In a specific embodiment 2 of the present invention, the 3D seismic data of the BN area of ​​the XX oil field is used as the target area, and the method is applied to process the data to verify the effect of the method. The specific flow chart is shown in FIG. Figure 5 The actual data was collected using a full-node acquisition method, with a seismic data time length of 7000ms and a time sampling interval of 1ms. The data was processed using the above method.

[0076] 1) First, go to step 1 and load the observation system and processing grid. After loading the observation system and processing grid, the relative position relationship between the shot points, the receiver points and the processing bins is clear.

[0077] 2) Then, according to step 2, the observation system parameters are extracted from the seismic data after the observation system is loaded, and the number of times the bin is covered is calculated according to the formula.

[0078] 3) According to step 3, calculate the coverage normalization factor according to the formula.

[0079] Obtain the regional energy scaling factor for each seismic trace.

[0080] 4) According to step 4, determine the area of ​​the acquisition observation system arrangement slice where the seismic trace is located.

[0081] 5) Based on step 5, the region is divided according to the actual coordinates of the seismic traces.

[0082] 6) According to step 6, the regional relative energy proportional factor of each seismic trace and the surrounding seismic traces is calculated.

[0083] 7) According to step 7, the seismic trace energy compensation factor is calculated according to the formula. According to the characteristics of the work area, the empirical parameters are taken as 0.4 and 0.5 respectively.

[0084] 8) According to step 8, apply the earthquake energy compensation factor to the seismic trace, Figure 1 and Figure 3 It is a display before application. Figure 2 and Figure 4 This is the demonstration after application. It can be seen that the energy distribution of the seismic data has been well processed, and the seismic profile effect is more ideal, which shows that this method is indeed feasible and has outstanding results.

[0085] Example 3:

[0086] In the specific embodiment 3 of the present invention, the 3D seismic data of the CH area of ​​XX oil field is used as the target area, and the method is applied to process the data to verify the effect of the method. The specific flow chart is shown in FIG. Figure 5 The actual data was collected using a full-node acquisition method, with a seismic data time length of 6000ms and a time sampling interval of 2ms. The data was processed using the above method.

[0087] 1) First, go to step 1 and load the observation system and processing grid. After loading the observation system and processing grid, the relative position relationship between the shot points, the receiver points and the processing bins is clear.

[0088] 2) Then, according to step 2, the observation system parameters are extracted from the seismic data after the observation system is loaded, and the number of times the bin is covered is calculated according to the formula.

[0089] 3) According to step 3, calculate the coverage normalization factor according to the formula.

[0090] Obtain the regional energy scaling factor for each seismic trace.

[0091] 4) According to step 4, determine the area of ​​the acquisition observation system arrangement slice where the seismic trace is located.

[0092] 5) Based on step 5, the region is divided according to the actual coordinates of the seismic traces.

[0093] 6) According to step 6, the regional relative energy proportional factor of each seismic trace and the surrounding seismic traces is calculated.

[0094] 7) According to step 7, the seismic trace energy compensation factor is calculated according to the formula. According to the characteristics of the work area, the empirical parameters are taken as 0.3 and 0.7 respectively.

[0095] 8) According to step 8, apply the earthquake energy compensation factor to the seismic trace, Figure 6 It is a display before application. Figure 7This is the display after application. It can be seen that before application, the energy distribution within the seismic data vector slice was uneven and the energy consistency was poor. After application, the energy distribution of the seismic trace was uniform and the consistency was good, indicating that this method is indeed feasible and has outstanding results.

[0096] Finally, it should be noted that the above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art may modify the technical solutions described in the aforementioned embodiments or substitute equivalents for some of the technical features therein. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention shall be included within the scope of protection of the present invention.

[0097] Except for the technical features described in the specification, all other technical features are known technologies to those skilled in the art.

Claims

1. A method for processing prestack energy consistency of full-node seismic data, characterized by: The full-node seismic data pre-stack energy consistency processing method includes: Step 1: Load the observation system and processing grid; Step 2, calculate the number of coverages within the bin; Step 3, calculate the coverage normalization factor; Step 4, determine the subdivision area; Step 5, perform regional segmentation; Step 6, calculate the regional energy scaling factor; Step 7, obtaining the seismic trace energy compensation factor; Step 8, applying the earthquake energy compensation factor; In step 5, use the actual coordinates of the seismic traces as points and connect all adjacent points. This will form triangles with adjacent seismic traces as vertices. Draw the perpendicular bisectors of each triangle so that each seismic trace is surrounded by a unique polygon. In step 6, the energy value of each polygon is represented by the seismic traces it encloses, and the energy distribution in the entire area is calculated, and then the regional relative energy ratio factor of each seismic trace and the surrounding seismic traces is calculated; In step 7, the normalization factor N obtained in the above steps is i and regional relative energy scaling factor M i Calculate the seismic trace energy compensation factor K i : K i = aN i + bM i (Equation 3) Among them, a i , b i is an empirical parameter.

2. The method for processing prestack energy consistency of full-node seismic data according to claim 1, characterized in that: In step 1, the seismic data and survey results collected in the field are merged and loaded into the processing grid.

3. The method for processing prestack energy consistency of full-node seismic data according to claim 1, characterized in that: In step 2, after loading the observation system and processing grid, count the number of coverages within the bin: Among them, F is the number of coverage, R sn To arrange the number of single-line receiving channels, R sd is the track distance, R n is the number of receiving lines, R d is the receiving line distance, L s S is the least common multiple of the receiving track spacing and the gun row spacing, g It is the least common multiple of the shot point distance and the receiving line distance.

4. The method for processing prestack energy consistency of full-node seismic data according to claim 1, characterized in that: In step 3, the normalization factor of the coverage of the seismic trace is the inverse of the coverage of the bin in which it is located: Among them, N i is the normalization factor of the ith channel, and F is the number of times the bin of the ith channel is covered.

5. The method for processing prestack energy consistency of full-node seismic data according to claim 1, characterized in that: In step 4, based on the seismic data header information after loading the observation system, the area range of the acquisition arrangement slice where the seismic trace is located is determined. For conventional seismic acquisition, this area is rectangular, but for full-node acquisition data, this area is affected by the node data cutting and is an asymmetric polygon.

6. The method for processing prestack energy consistency of full-node seismic data according to claim 1, characterized in that: In step 8, the obtained compensation factor is applied to the seismic trace to complete the pre-stack energy consistency processing of the full-node seismic data.

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