A target-oriented seismic acquisition method, device, medium and equipment

Abstract

The present invention relates to a target-oriented seismic acquisition method, device, medium and equipment. The target-oriented seismic acquisition method comprises the following steps: for an underground target position, an initial velocity model and three-dimensional seismic observation system parameters are given; the three-dimensional seismic observation system is subjected to wave field extension and focusing analysis to calculate the ground seismic energy distribution of the underground target area; the ground seismic energy distribution is normalized and then graded to obtain a primary energy zone and a secondary energy zone; the number of shot points is increased in the primary energy zone to achieve target-oriented acquisition and obtain a target-oriented non-uniform laying acquisition data imaging effect; the conventional acquisition data imaging result is compared with the target-oriented non-uniform laying acquisition data imaging effect. The method of the present invention realizes automatic feedback adjustment of the excitation and receiving positions and their parameters.

Description

Technical Field

[0001] The invention relates to a target-oriented seismic acquisition method, device, medium and equipment, and belongs to the field of optimization design of three-dimensional observation system for petroleum seismic exploration. Background Art

[0002] 3D seismic exploration is the main means of oil and gas exploration. The data collected by seismic exploration must go through processes such as processing, imaging, and inversion to obtain the underground structural characteristics and lithological parameters. Therefore, the quality of seismic acquisition data is crucial to the clarity of identifying underground targets.

[0003] Traditional seismic acquisition is to evenly lay out shot points and receiver points on the ground. The underlying theory is to assume that the underground strata are horizontal media and that seismic waves illuminate evenly, but the actual strata are not horizontal. For most flat strata, the seismic waves excited by the ground shot points can be reflected at a small angle and received by the ground detectors; while high-steep faults produce high-angle reflections, and the signals cannot be received by the ground detectors, making it impossible to see the steep-angle strata and faults clearly. Therefore, how to make high-angle seismic waves be received by ground detectors is the core issue of seismic acquisition technology. Summary of the invention

[0004] In view of the above technical problems, the present invention provides a target-oriented seismic acquisition method, device, medium and equipment. The method of the present invention abandons the idea of ​​uniformly laying the acquisition observation system on the ground. Since the high-angle waves generated by the excitation within the ground observation range cannot be received by the ground detector, the high-angle waves reflected by the steep-angle interface can be received by the detector within the ground observation range by excitation outside the ground observation range. In addition, the number of shot points in some areas is increased, so that more effective underground information can be obtained under the current seismic acquisition observation system conditions, and finally the seismic observation system design for a specific geological target body is completed, providing the best initial data for subsequent seismic data processing, interpretation, inversion, etc.

[0005] To achieve the above object, the present invention adopts the following technical solutions:

[0006] A target-oriented seismic acquisition method comprises the following steps:

[0007] For the underground target location, the initial velocity model and the parameters of the 3D seismic observation system are given;

[0008] Conduct wave field extension and focusing analysis on the 3D seismic observation system and calculate the surface seismic energy distribution in the underground target area;

[0009] The ground seismic energy distribution is normalized and then graded to obtain primary energy zone and secondary energy zone;

[0010] Increase the number of shot points in the primary energy zone to achieve target-oriented acquisition and obtain target-oriented non-uniform paving acquisition data imaging effect;

[0011] The imaging results of conventional acquisition data are compared with those of target-oriented non-uniform paving acquisition data.

[0012] The target-oriented seismic acquisition method preferably performs wave field extension and focusing analysis on the three-dimensional seismic observation system to calculate the ground seismic energy distribution in the underground target area, and the specific steps are as follows:

[0013] FFD is used for large-step extension, combined with Born-Kirchhoff interpolation, to obtain the wave fields of each small layer between the large step sizes. After completing the wave field extension, the focusing properties of the detection points and the shot points of the 3D seismic observation system are calculated respectively, and then the expected resolution and AVP properties of the entire 3D seismic observation system are quantitatively analyzed, and the ground seismic energy distribution in the underground target area is calculated.

[0014] The target-oriented seismic acquisition method preferably normalizes the ground seismic energy distribution and then performs hierarchical partitioning, and the specific steps are as follows:

[0015] The energy drop is limited to 1 / e, the upper limit is the first-level energy zone, and the lower limit is the energy drop of 1 / 2 is the second-level energy zone.

[0016] A second aspect of the present invention provides a target-oriented seismic acquisition device, comprising:

[0017] A first processing unit is used to give an initial velocity model and three-dimensional seismic observation system parameters for an underground target location;

[0018] The second processing unit is used to perform wave field extension and focusing analysis on the three-dimensional seismic observation system and calculate the surface seismic energy distribution in the underground target area;

[0019] The third processing unit is used to normalize the ground seismic energy distribution and then perform hierarchical partitioning to obtain primary energy zones and secondary energy zones;

[0020] The fourth processing unit is used to increase the number of shot points in the primary energy zone to achieve target-oriented acquisition and obtain target-oriented non-uniform paving acquisition data imaging effect;

[0021] The fifth processing unit is used to compare the imaging result of the conventional acquisition data with the imaging effect of the target-oriented non-uniform paving acquisition data.

[0022] A third aspect of the present invention provides a computer-readable storage medium having a computer program stored thereon, wherein the computer program, when executed by a processor, implements the steps of the above-mentioned target-oriented seismic acquisition method.

[0023] 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 the processor implements the steps of the above-mentioned target-oriented seismic acquisition method when executing the computer program.

[0024] The present invention adopts the above technical solution, which has the following advantages:

[0025] 1. The present invention combines Born-Kirchhoff small-step wavefield interpolation (BK interpolation) with large-step FFD extension (FFD-BK for short) to perform wavefield recursive calculation, which significantly improves the simulation speed.

[0026] 2. Based on the principle of wave propagation, the target illumination is maximized and the optimization problem is solved to obtain the best ground excitation and receiving position. Based on this, an underground target-oriented non-uniform ground laying seismic acquisition design method is formed, which realizes the automatic feedback adjustment of the excitation and receiving positions and their parameters.

[0027] 3. Compared with conventional data acquisition imaging, target-oriented non-uniform paving data acquisition imaging significantly improves the imaging effect of high-steep structures and small fault blocks, increases the acquisition range of high-angle seismic waves from 45° to nearly 60°, and greatly improves the detection ability of seismic acquisition technology for complex structures. The present invention can be widely used in the field of optimization design technology of three-dimensional observation system for petroleum seismic exploration. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] Figure 1 A flow chart of a target-oriented seismic acquisition method provided by an embodiment of the present invention;

[0029] Figure 2 A schematic diagram of confocal analysis in a complex medium provided by this embodiment of the present invention;

[0030] Figure 3 A schematic diagram of a Fourier finite difference (FFD) large step size combined with a Born-Kirchhoff small step size extension algorithm provided in this embodiment of the present invention;

[0031] Figure 4 The surface seismic energy distribution of the underground target area provided by this embodiment of the present invention;

[0032] Figure 5 The energy distribution diagram provided for this embodiment of the present invention, wherein a is a schematic diagram of energy distribution corresponding to conventional shot points, and b is a schematic diagram of energy distribution corresponding to the addition / position adjustment of shot points of the present invention;

[0033] Figure 6Comparison of data imaging after target-oriented acquisition (b) and traditional acquisition (a) provided in this embodiment of the present invention - taking a target area of ​​Zhongyuan Oilfield as an example;

[0034] Figure 7 Comparison of data imaging after target-oriented acquisition (b) and traditional acquisition (a) provided in this embodiment of the present invention - taking a target area in Dagang Oilfield as an example. DETAILED DESCRIPTION

[0035] In order to make the purpose, technical solution and advantages of the present invention clearer, the technical solution in the present invention is described clearly and completely below. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary persons in the art without creative work are within the scope of protection of the present invention.

[0036] like Figure 1 As shown, the target-oriented seismic acquisition method provided by the present invention comprises the following steps:

[0037] 1) Given the initial velocity model and 3D seismic observation system parameters for the underground target location;

[0038] 2) Use FFD to perform large step extension and combine Born-Kirchhoff interpolation to obtain the wave fields of each small layer between large step lengths (such as Figure 2 As shown, it is done once every five layers). The FFD large step extension algorithm is an existing technology (see application number 201010557332.1, invention name: A patent for a method and device for acquiring offset noise in a three-dimensional seismic observation system), so the FFD large step extension is not repeated here. Since the simple use of FFD wave field extension technology requires a huge amount of calculation, this application proposes FFD combined with Born-Kirchhoff interpolation technology, and uses the Lippmann-Schwinger integral formula to derive the Born-Kirchhoff interpolation wave field u(r):

[0039]

[0040] in,

[0041]

[0042] Where n is the reflection coefficient, k0 is the background wave number, i is a pure imaginary number, the position of the target point before extension is (x1, y2), the position of the target point after extension is (x2, y2), the ordinate of the target point before extension is z, and the difference in ordinates before and after extension is Δz, u s (r) is the wave field before extension.

[0043] like Figure 3 As shown, the wave field is located at the target point r t The source grid point at is propagated through the inhomogeneous medium v(x,y,z) to the receiver point located at z0 on the ground. The focusing characteristics of the observation system at the target point are estimated by the inverse continuation of the observed seismic wave field. Z0 is the ground ordinate, z m is the ordinate of the target point.

[0044] After completing the wave field extension, the receiver point focusing attributes and the shot point focusing attributes of the three-dimensional seismic observation system are calculated respectively (for the detailed calculation or analysis process of the receiver point focusing attributes and the shot point focusing attributes, please refer to the patent application number 201710081114.7, the invention name is: A patent for quantitative analysis and evaluation method of vertical resolution of a three-dimensional seismic observation system), and then the expected resolution and AVP attributes of the entire observation system are obtained in the spatial frequency domain and the Radon domain respectively, and the ground energy distribution of the underground target area is given (such as Figure 4 shown).

[0045] In this step, the overall extension based on the three-dimensional seismic observation system is completed by the large-step extension of Fourier finite difference (FFD) and the small-step wave field interpolation of the Born-Kirchhoff operator; the large-step extension of Fourier finite difference (FFD) is an existing technology and will not be repeated here. Since the Born-Kirchhoff integral formula under the condition of small angle of incident wave adds a slowness disturbance correction term compared with the Kirchhoff integral formula under uniform conditions, the operator can adapt to the lateral change of medium velocity. After the wave field extension, the confocal analysis is performed through the detection point, the shot point and the underground target body to obtain the resolution function and the AVP function (Amplitude versus ray-parameter). Confocal analysis is an existing technology (see application number 201710081114.7, the invention name is: a patent for a method for quantitative analysis and evaluation of vertical resolution of a three-dimensional seismic observation system), which will not be repeated here.

[0046] 3) Normalize the ground seismic energy distribution and then divide it into different levels. The energy drop of 1 / e is set as the upper limit, and the energy drop of 1 / 2 is set as the second level energy zone;

[0047] 4) In addition to the conventionally designed shot points and receiver points, the number of shot points is increased in the above-mentioned primary energy zone to achieve target-oriented acquisition (such as Figure 5 This design scheme is used as the basis for improving the design of three-dimensional seismic observation system.

[0048] First, the positions of shot points and receiver points are given to form an underground target-oriented non-uniform ground seismic acquisition design method, which is "increasing the number of shot points in the primary energy zone" as mentioned in step 4).

[0049] The result obtained here is the data collected by seismic. The result is that after the adjusted shot point and receiver point design, data collection will be carried out. The collected data will then be processed and imaged by seismic to obtain Figure 6 Imaging results on the right and 7 on the right. Figure 6 Left and Figure 7 The image on the left shows that the shot points and receiver points are not adjusted, and the observation system is evenly laid out. The data collected in this way can be processed and imaged by seismic processing to obtain Figure 6 Left and Figure 7 Left side.

[0050] 5) Apply the above analysis method to the actual area and compare the imaging results based on conventional acquisition data with the imaging results based on target-oriented non-uniform paving acquisition data (such as Figure 6 and Figure 7 ). Figure 6 and Figure 7 It can be seen that the traditional method cannot identify the target and the fracture, while the method of the present invention can clearly identify the target features and the fracture features.

[0051] A second aspect of the present invention provides a target-oriented seismic acquisition device, comprising:

[0052] A first processing unit is used to give an initial velocity model and three-dimensional seismic observation system parameters for an underground target location;

[0053] The second processing unit is used to perform wave field extension and focusing analysis on the three-dimensional seismic observation system and calculate the surface seismic energy distribution in the underground target area;

[0054] The third processing unit is used to normalize the ground seismic energy distribution and then perform hierarchical partitioning to obtain primary energy zones and secondary energy zones;

[0055] The fourth processing unit is used to increase the number of shot points in the primary energy zone to achieve target-oriented acquisition and obtain target-oriented non-uniform paving acquisition data imaging effect;

[0056] The fifth processing unit is used to compare the imaging result of the conventional acquisition data with the imaging effect of the target-oriented non-uniform paving acquisition data.

[0057] A third aspect of the present invention provides a computer-readable storage medium having a computer program stored thereon, wherein the computer program, when executed by a processor, implements the steps of the above-mentioned target-oriented seismic acquisition method.

[0058] 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 the processor implements the steps of the above-mentioned target-oriented seismic acquisition method when executing the computer program.

[0059] 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 the 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.

[0060] These computer program instructions may also be stored in a computer-readable memory capable of directing a computer or other programmable data processing device to operate 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 A function specified in one or more boxes.

[0061] These computer program instructions can also be loaded onto a computer or other programmable data processing device so that a series of operating steps are executed on the computer or other programmable device to produce a computer-implemented process, thereby providing instructions for implementing the process. Figure 1 A process or multiple processes and / or boxes Figure 1 The steps for the functions specified in one or more boxes.

[0062] 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 embodiments of the present invention.

Claims

1. A target-oriented seismic acquisition method, characterized in that: The steps include: For the underground target location, the initial velocity model and the parameters of the 3D seismic observation system are given; Conduct wave field extension and focusing analysis on the 3D seismic observation system and calculate the surface seismic energy distribution in the underground target area; The ground seismic energy distribution is normalized and then graded to obtain primary energy zone and secondary energy zone; Increase the number of shot points in the primary energy zone to achieve target-oriented acquisition and obtain target-oriented non-uniform paving acquisition data imaging effect; Compare the imaging results of conventional acquisition data with those of target-oriented non-uniform paving acquisition data; The wave field extension and focusing analysis of the 3D seismic observation system is performed to calculate the ground seismic energy distribution in the underground target area. The specific steps are as follows: FFD is used for large-step extension, combined with Born-Kirchhoff interpolation, to obtain the wave fields of each small layer between large step lengths. After completing the wave field extension, the focusing properties of the receiver points and the shot points of the 3D seismic observation system are calculated respectively, and then the expected resolution and AVP properties of the entire 3D seismic observation system are quantitatively analyzed. The ground seismic energy distribution of the underground target area is calculated, and the wave field u(r) obtained by Born-Kirchhoff interpolation is derived using the Lippmann-Schwinger integral formula: in, Where n is the reflection coefficient, k0 is the background wave number, i is a pure imaginary number, the position of the target point before extension is (x1, y2), the position of the target point after extension is (x2, y2), the ordinate of the target point before extension is z, and the difference in ordinates before and after extension is Δz, u s (r) is the wave field before extension; The ground seismic energy distribution is normalized and then graded. The specific steps are as follows: The energy drop is limited to 1 / e, the upper limit is the first-level energy zone, and the lower limit is the energy drop of 1 / 2 is the second-level energy zone.

2. A target-oriented seismic acquisition device, characterized in that: include: A first processing unit is used to give an initial velocity model and three-dimensional seismic observation system parameters for an underground target location; The second processing unit is used to perform wave field extension and focusing analysis on the 3D seismic observation system and calculate the ground seismic energy distribution in the underground target area. The FFD is used for large step extension and Born-Kirchhoff interpolation is combined to obtain the wave fields of each small layer between the large step lengths. After completing the wave field extension, the focusing properties of the detection points and the focusing properties of the shot points of the 3D seismic observation system are calculated respectively, and then the expected resolution and AVP properties of the entire 3D seismic observation system are quantitatively analyzed. The ground seismic energy distribution in the underground target area is calculated, and the wave field u(r) obtained by Born-Kirchhoff interpolation is derived using the Lippmann-Schwinger integral formula: in, Where n is the reflection coefficient, k0 is the background wave number, i is a pure imaginary number, the position of the target point before extension is (x1, y2), the position of the target point after extension is (x2, y2), the ordinate of the target point before extension is z, and the difference in ordinates before and after extension is Δz, u s (r) is the wave field before extension; The third processing unit is used to normalize the ground seismic energy distribution and then perform hierarchical partitioning to obtain the primary energy zone and the secondary energy zone; the ground seismic energy distribution is normalized and then graded partitioning is performed, and the specific steps are as follows: the energy drop of 1 / e is taken as the limit, the upper limit is the primary energy zone, and the lower limit to the energy drop of 1 / 2 is the secondary energy zone; The fourth processing unit is used to increase the number of shot points in the primary energy zone to achieve target-oriented acquisition and obtain target-oriented non-uniform paving acquisition data imaging effect; The fifth processing unit is used to compare the imaging result of the conventional acquisition data with the imaging effect of the target-oriented non-uniform paving acquisition data.

3. 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 target-oriented seismic acquisition method according to claim 1 are implemented.

4. A computer device comprising a memory, a processor and a computer program stored in the memory and executable on the processor, characterized in that: When the processor executes the computer program, the steps of the target-oriented seismic acquisition method according to claim 1 are implemented.

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