Acquisition parameter analysis method for weakening influence of surface secondary noise

Abstract

The invention provides an acquisition parameter analysis method for weakening the influence of surface secondary noise. The acquisition parameter analysis method for weakening the influence of surface secondary noise comprises the following steps: step 1, establishing a comprehensive geologic model comprising a surface, a near-surface and a deep layer; 2, comparing the simulated single shot with the actual single shot, and adjusting the comprehensive geologic model; step 3, setting the arrangement length and the geophone density to simulate and analyze the CMP gather; step 4, modifying the simulated single shot head into a CMP gather; and step 5, analyzing an arrangement length coverage frequency acquisition demand. According to the acquisition parameter analysis method for weakening the surface secondary noise influence, the near-surface noise influence can be effectively considered, the deep acquisition parameter requirement can be analyzed, and the acquisition factor selection correctness for the deep target can be effectively improved.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of oilfield development, and particularly relates to a method for analyzing acquisition parameters for weakening the influence of surface secondary noise. BACKGROUND

[0002] The deep layer of the Junggar Basin is rich in oil and gas resources, but the surface is a thick desert, and the sand layer is loose, which seriously absorbs and attenuates seismic waves. In addition, the surface undulates greatly, generating a large number of near-surface interference waves, which makes the signal-to-noise ratio of seismic data low, and makes it difficult to collect seismic data. The signal-to-noise ratio of the obtained seismic data is low, which makes it difficult to meet the oil and gas exploration in the desert area. Therefore, how to select appropriate acquisition methods for deep geological targets is particularly important. However, there is no corresponding method in the past, and if actual data testing is used, a lot of cost and time will be paid. If the method of previous theoretical simulation is used, accurate analysis conclusions cannot be obtained. The simulation of a single shot is quite different from the actual single shot, and the simulation workload of thousands of shots is huge, which makes it impossible to obtain the desired conclusions.

[0003] In the Chinese patent application with the application number: CN202010593869.7, a method for analyzing seismic acquisition parameters based on pre-stack migration imaging of geological targets is disclosed, which includes: redefining a large grid according to the observation system and the geological characteristics of the target area, and forming a new data body according to the large grid; performing pre-stack time migration velocity analysis using the full data body data to form a final pre-stack time migration velocity body; using the new data body, dividing the data into different data bodies according to different field acquisition parameters; using the final pre-stack time migration velocity body, performing pre-stack time migration processing on all data bodies and different acquisition parameter data bodies; performing signal-to-noise ratio analysis, resolution analysis and fracture system analysis on the results of pre-stack time migration processing of all data bodies and different acquisition parameter data bodies; and determining a seismic acquisition scheme that can meet the requirements of the geological target. This method can effectively analyze the degree of description of seismic data obtained by different acquisition parameters on the geological target, and effectively determine the best acquisition parameters. However, the data volume of this application is too large, especially for three-dimensional model simulation, which is generally not possible. The simulation data volume and processing workload are too large, greatly exceeding the cost pressure, and the analysis efficiency is too low.

[0004] In the Chinese patent application with the application number CN201410691159.2, a method and system for determining seismic data acquisition parameters are involved. The method comprises: performing frequency scanning on original seismic data to screen out an effective seismic data time window; obtaining a seismic dominant frequency band in the effective seismic data time window; calculating a correlation coefficient and a linear coefficient between a single-frequency wavelet spectrum and a theoretical wavelet spectrum corresponding to the frequency in the seismic dominant frequency band; and determining the seismic data acquisition parameters according to the correlation coefficient and the linear coefficient between the single-frequency wavelet spectrum and the theoretical wavelet spectrum corresponding to the frequency. The method and system provided by the application embodiment can determine the optimal seismic data acquisition parameters by performing quantitative analysis on wavelet data and comprehensively comparing the correlation coefficient and the linear coefficient. However, the application can only obtain the optimal acquisition parameters by the correlation coefficient and the linear coefficient, and cannot obtain the effective frequency range of the actual data or determine the optimal acquisition parameters.

[0005] In the Chinese patent application with the application number CN202010524129.8, a method for analyzing geophysical exploration parameters in oil exploration and application thereof are involved, which comprises the following steps: (1) collecting design parameters in a geophysical exploration project according to well logging interpretation data and seismic interpretation data; (2) determining a collection data amount according to the design parameters; the collection data amount is the sum or product of the design parameters; and (3) constructing a linear regression equation between the collection data amount and project investment amount according to the collection data amount, which satisfies the following relationship: y=kx+b, wherein y is the investment amount, x is the collection data amount, and k and b are constants. The analysis method provided in the application eliminates the influence of parameters such as bin and coverage times on investment, and objectively and truly reflects the actual workload of the geophysical exploration project collection through the geophysical exploration collection data amount. In addition, the method is more scientific and reasonable than the previous experience-based method or simple fixed metering pricing method, and can avoid the estimation inaccuracy caused by subjectivity. The application only calculates the size of the geophysical exploration collection data amount, and does not involve the analysis of collection parameters.

[0006] The above prior art has great differences from the present application and cannot solve the technical problems we want to solve. Therefore, we have invented a new collection parameter analysis method for weakening the influence of surface secondary noise. SUMMARY

[0007] The purpose of the present application is to provide a collection parameter analysis method for weakening the influence of surface secondary noise, which fully considers the near-surface noise factor, can effectively suppress the influence of noise, and analyzes suitable collection parameters.

[0008] The purpose of the present application can be achieved by the following technical measures: a collection parameter analysis method for weakening the influence of surface secondary noise, which comprises:

[0009] Step 1, a comprehensive geological model including surface, near-surface and deep layer is established;

[0010] Step 2, the simulated single shot is compared with the actual single shot, and the comprehensive geological model is adjusted;

[0011] Step 3, the arrangement length and the receiver density are set to simulate and analyze CMP gathers;

[0012] Step 4, the simulated single shot trace head is modified to CMP gathers;

[0013] Step 5, the arrangement length coverage times acquisition requirement is analyzed.

[0014] The purpose of the application can also be achieved through the following technical measures:

[0015] In step 1, according to the geological structure of the work area and the near-surface and surface investigation, a comprehensive geological model including surface, near-surface and deep layer is established, the surface includes elevation data; the near-surface includes low-velocity layer, velocity reduction layer, high-velocity layer velocity, thickness and position information; the deep layer information includes the position and velocity information of each layer.

[0016] In step 2, the single shot simulation is compared with the actual single shot, the signal-to-noise ratio difference between the two is analyzed, and then the geological model is adjusted until the signal-to-noise ratio difference between the simulated single shot and the actual single shot is small; after adjusting the comprehensive model, the acquisition parameter analysis for deep imaging requirement is carried out.

[0017] In step 2, after the establishment of the comprehensive model, single shot simulation is carried out, and the simulation is compared with the actual single shot, well shot can be used for excitation, the shot point is placed below the top interface of the high-velocity layer for excitation, or the controllable source can be used for excitation, the shot point is placed on the surface for excitation; using these two excitation methods, the obtained data will have great difference; and compared with the actual single shot respectively.

[0018] In step 2, when the well shot is used for excitation, the obtained single shot is compared with the actual well shot data, the signal-to-noise ratio of the single shot is required to be basically equivalent, and the obtained surface interference wave energy is basically equivalent, if the signal-to-noise ratio difference between the simulated single shot and the actual single shot is large, the velocity of the near-surface model needs to be adjusted, so that the signal-to-noise ratio of the simulated single shot and the actual single shot is basically equivalent.

[0019] In step 2, when the controllable source single shot is excited, the obtained single shot is compared with the actual well shot data, the signal-to-noise ratio of the single shot is required to be basically equivalent, and the obtained surface interference wave energy is basically equivalent, if the signal-to-noise ratio difference between the simulated single shot and the actual single shot is large, the velocity of the near-surface model needs to be adjusted, so that the signal-to-noise ratio of the simulated single shot and the actual single shot is basically equivalent.

[0020] In step 3, the arrangement length is equal to the depth of the deepest target layer + 1000m; then the geophone trace interval is set, the geophone trace interval = arrangement length / target coverage number, and the target coverage number is the maximum coverage number used in this analysis.

[0021] In step 3, after setting the arrangement length and trace interval, the shot point is placed at one end of the arrangement, and the shot point is placed below the top interface of the high-speed layer for well shooting, and the shot point is placed on the ground for controlled source shooting; after simulation, the simulated record is processed by static correction to eliminate the time difference caused by surface relief.

[0022] In step 4, the record head is modified, and the original single-shot record head is modified to the same CMP gather, and the record is taken as a CMP gather for stacking of different arrangement lengths and different coverage numbers.

[0023] In step 5, the stacked record is compared with the model, and it is analyzed which arrangement length and coverage number can better suppress near-surface noise and obtain reflection information with high signal-to-noise ratio.

[0024] In step 5, a single-channel data can be obtained by stacking in step 4, and 20 copies of the single-channel data are made to form a "small profile". Since the model stratum is flat, the copied "small profile" also shows a flat stratum, which can be better corresponded. According to the position of the shot point, the "small profile" is placed in the corresponding position of the model, and it is analyzed whether the reflection axis in the "small profile" corresponds to the model layer one by one and whether the signal-to-noise ratio of the reflection axis is sufficient to meet the requirement of distinguishing strata. By using this comparison and analysis method, it is analyzed that the "small profile" obtained by using how large arrangement length and how large coverage number can better suppress near-surface noise and obtain reflection information with high signal-to-noise ratio.

[0025] The object of the application can also be achieved by the following technical measures:

[0026] The deep layer acquisition parameter demand analysis system considering the near-surface noise influence factor adopts the acquisition parameter analysis method weakening the influence of surface secondary noise to analyze the acquisition parameter demand of the deep layer, and selects the acquisition factors of the deep target.

[0027] The acquisition parameter analysis method for mitigating the effects of secondary surface noise, described in this invention, involves deep seismic acquisition parameter selection technology. Specifically, it utilizes a comprehensive geological model encompassing the surface and near-surface for forward modeling. By converting simulated single-shot modified traces into CMP gathers, the CMP gathers are stacked with different acquisition parameters to determine optimal deep-seated acquisition parameters based on the resulting stacking. This method, focusing on deep-seated acquisition parameter selection, fully considers near-surface noise factors, effectively suppresses the effects of noise, and analyzes appropriate acquisition parameters, which is of great significance for improving deep-seated oil and gas exploration. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] Figure 1 This is a flow chart of a specific embodiment of the acquisition parameter analysis method for reducing the impact of secondary noise on the surface of the present invention;

[0029] Figure 2 This is a diagram showing the effect obtained by using this method in a specific embodiment of the present invention. DETAILED DESCRIPTION

[0030] 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.

[0031] 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.

[0032] like Figure 1 As shown, Figure 1 The flowchart of the acquisition parameter analysis method for weakening the influence of secondary surface noise of the present invention is as follows. The acquisition parameter analysis method for weakening the influence of secondary surface noise includes:

[0033] Step 101: Establish a comprehensive geological model including the surface, near-surface, and deep layers.

[0034] Based on the geological structure of the work area and the near-surface and surface survey results, a comprehensive geological model covering the surface, near-surface, and deep layers was established. The surface includes elevation data, while the near-surface includes velocity, thickness, and location information for the low-velocity layer, the decreasing velocity layer, and the high-velocity layer. Deep layer information includes the location and velocity of each layer.

[0035] Step 102 : Compare the simulated single shot with the actual single shot and adjust the model.

[0036] By single shot simulation and actual single shot comparison, analyze the difference between the two signal to noise ratio, and then adjust the geological model until the simulated single shot and the actual single shot signal to noise ratio difference is not big.

[0037] After the establishment of the integrated model, single shot simulation is carried out, and the simulation is compared with the actual single shot. For example, if well shot is used for excitation, the shot point is placed below the top interface of high speed layer for excitation, and if controlled source is used for excitation, the shot point is placed on the ground for excitation. Using these two excitation methods, the obtained data will have great difference. And respectively compared with the actual single shot. When using well shot for excitation, the obtained single shot is compared with the actual well shot data, and the single shot signal to noise ratio is required to be basically equivalent, and the obtained surface interference wave energy is basically equivalent. If the signal to noise ratio of the simulated single shot and the actual single shot is large, the velocity of the near surface model needs to be adjusted, so that the signal to noise ratio of the simulated single shot and the actual single shot is basically equivalent. Similarly, the same adjustment method is adopted for the controlled source single shot. After adjusting the integrated model, the acquisition parameter analysis is carried out for the imaging requirement of deep layer.

[0038] Step 103, set the arrangement length and the geophone point density to simulate and analyze the CMP gather. The arrangement length is equal to the depth of the deepest target layer + 1000m. Then set the geophone trace interval, geophone trace interval = arrangement length / target coverage times, target coverage times is the maximum coverage times used in this analysis. After setting the arrangement length and trace interval, the shot point is placed at one end of the arrangement, such as well shot excitation, the shot point is placed below the top interface of high speed layer for excitation, such as controlled source excitation, the shot point is placed on the ground for excitation. After simulation, the simulated record is processed by static correction to eliminate the time difference caused by surface relief.

[0039] As shown in Figure 2 a, the model is simulated by a single shot, the shot point is placed at one end of the arrangement, the single shot record is simulated, and then the record is processed by dynamic correction to flatten the same phase axis. Figure 2 a is a single shot simulated on the model, the shot point is placed at one end of the arrangement, the single shot record is simulated, and then the record is processed by dynamic correction to flatten the same phase axis.

[0040] Step 104, modify the head of the simulated single shot to CMP gather. Modify the record head, modify the original single shot record head to the same CMP gather, and stack the record as a CMP gather with different arrangement lengths and different coverage times.

[0041] Figure 2 b is the dynamic correction of the single shot, at this time the same phase axis has been flattened, then the record head is modified to the same CMP gather, then different shot-geophone distance and different coverage times can be stacked.

[0042] Step 105, analyze the arrangement length coverage times collection requirement. The superimposed record is compared with the model, and which arrangement length and coverage times can better suppress the near-surface noise and obtain the reflection information with high signal-to-noise ratio is analyzed. By using the method, the deep layer collection parameter requirement can be effectively analyzed considering the near-surface noise influence, and the correctness of the collection factor selection for the deep layer target can be effectively improved.

[0043] The following are several specific embodiments of the application

[0044] Embodiment 1

[0045] In the specific embodiment 1 of the application, the application can effectively select the appropriate collection parameters for the deep geological target considering the near-surface noise influence factors, including first establishing a comprehensive geological model including the surface, the near-surface and the deep layer according to the geological structure situation and the near-surface and surface investigation situation of the work area, the surface includes the elevation fluctuation data, the near-surface includes the low-velocity layer, the speed, thickness and position information of the low-velocity layer, the high-velocity layer and the deep layer information includes the position and speed information of each layer.

[0046] After the comprehensive model is established, single shot simulation is performed, and the simulation situation is compared with the actual single shot. For example, the well shot is used for excitation, and the shot point is placed below the top interface of the high-velocity layer for excitation, and the controllable source is used for excitation, and the shot point is placed on the surface for excitation. The data obtained by using the two excitation methods will have great difference. And respectively compared with the actual single shot. When the well shot is used for excitation, the obtained single shot is compared with the actual well shot data, the signal-to-noise ratio of the single shot is required to be basically equivalent, and the obtained surface interference wave energy is basically equivalent. If the signal-to-noise ratio of the simulation single shot and the actual single shot is greatly different, the speed of the near-surface model needs to be adjusted, so that the signal-to-noise ratio of the simulation single shot and the actual single shot is basically equivalent. The same adjustment method is also adopted for the controllable source single shot.

[0047] After the comprehensive model is adjusted, the collection parameter analysis for the imaging requirement of the deep layer is performed. The CMP gather is simulated and analyzed by setting the arrangement length and the geophone point density. The arrangement length is equal to the depth of the deepest target layer + 1000m, for example, the depth of the deepest target layer is 6700m, and the arrangement length is set to 7700m. Then the geophone point trace interval is set, the geophone point trace interval = arrangement length / target coverage times, the target coverage times is the maximum coverage times used in this analysis. For example, the arrangement length is 7000m, and the target coverage times is 1100 times, then the geophone point trace interval = 7700 / 1100 = 7m, and the trace interval is set to 7m. After the arrangement length and the trace interval are set, the shot point is placed at one end of the arrangement, for example, the well shot is excited, and the shot point is placed below the top interface of the high-velocity layer for excitation, and the controllable source is excited, and the shot point is placed on the surface for excitation.

[0048] After the simulation is completed, the simulation record is subjected to static correction processing to eliminate the time difference caused by surface relief. Then the record is modified by changing the original single shot record header to the same CMP gather, and the record is taken as a CMP gather to stack in different arrangement lengths and different coverages. For example, the arrangement length is set to 1000-7700 m, the increment is 100 m, the coverage is 500-1100 times, and the increment is 100 times, and the stacking is performed respectively. The stacked record is compared with the model to analyze which arrangement length and coverage can better suppress near-surface noise and obtain reflection information with high signal-to-noise ratio.

[0049] By using the method, the influence of near-surface noise on deep layer acquisition parameters can be effectively considered and analyzed, and the correctness of the selection of acquisition factors for deep layer targets can be effectively improved.

[0050] Embodiment 2

[0051] In the specific embodiment 2 of the application, the application can effectively select suitable acquisition parameters for the deep geological targets in the desert in southern Xinjiang under the consideration of the influence of near-surface noise, including first establishing a comprehensive geological model including the surface, near-surface and deep layer according to the deep geological structure and the near-surface and surface investigation in the desert in southern Xinjiang, the surface includes elevation relief data, the near-surface includes low-velocity layer, velocity-decreasing layer, high-velocity layer velocity, thickness and position information. The deep layer information includes the position and velocity information of each layer.

[0052] After the comprehensive model is established, single shot simulation is performed, and the simulation is compared with the actual single shot. For example, well shooting is used for excitation, and the shot point is placed below the top interface of the high-velocity layer for excitation, and controlled source is used for excitation, and the shot point is placed on the surface for excitation. The data obtained by using the two excitation methods will have great difference. The actual single shot is compared respectively. When the well shooting is used for excitation, the single shot obtained is compared with the actual well shooting data, the signal-to-noise ratio of the single shot is required to be basically equivalent, and the surface interference wave energy obtained is required to be basically equivalent. If the signal-to-noise ratio of the simulated single shot and the actual single shot is greatly different, the velocity of the near-surface model needs to be adjusted so that the signal-to-noise ratio of the simulated single shot and the actual single shot is basically equivalent. The same adjustment method is also adopted for the controlled source single shot.

[0053] After adjusting the comprehensive model, the parameter analysis for the deep imaging requirement is performed. The CMP gathers are simulated and analyzed by setting the array length and the receiver point density. The array length is equal to the depth of the deepest target layer + 1000 m, for example, if the depth of the deepest target layer is 8000 m, the array length is set to 9000 m. Then the receiver point trace interval is set, the receiver point trace interval = array length / target coverage times, the target coverage times is the maximum coverage times used in this analysis. For example, if the array length is 8000 m and the target coverage times is 1000 times, the receiver point trace interval = 8000 / 1000 = 8 m, and the trace interval is set to 8 m. After setting the array length and the trace interval, the shot points are placed at one end of the array, for example, the shot points are placed below the top interface of the high-speed layer for well shooting, and the shot points are placed on the ground surface for controlled source shooting.

[0054] After the simulation, the simulated record is processed by static correction to eliminate the time difference caused by the surface relief. Then the record header is modified from the original single shot record header to the same CMP gather, and the record is taken as a CMP gather for stacking with different array lengths and different coverage times. For example, the array length is set to 1000-8000 m with an increment of 100 m, and the coverage times is from 600-1000 times with an increment of 100 times, and the stacking is performed respectively. The stacked record is compared with the model to analyze which array length and coverage times can better suppress the near-surface noise and obtain the reflection information with high signal-to-noise ratio.

[0055] By using the method, the near-surface noise influence in the deep layer of the desert area in southern Xinjiang can be effectively considered to analyze the acquisition parameter requirement, and the correctness of the acquisition factor selection for the deep target in the desert in southern Xinjiang can be effectively improved.

[0056] Embodiment 3

[0057] In the specific embodiment 3 of the application, the application can effectively select the appropriate acquisition parameters for the geological target in the Qaidam Basin by considering the near-surface noise influence factors, including first establishing a comprehensive geological model containing the surface, the near-surface and the deep layer according to the geological structure of the Qaidam Basin and the near-surface and surface investigation, the surface includes the elevation relief data, the near-surface includes the low-speed layer, the speed, thickness and position information of the low-speed layer and the high-speed layer, and the deep layer information includes the position and speed information of each layer.

[0058] After the integrated model is established, single shot simulation is performed and compared with actual single shot. For example, if well shot is used for excitation, the shot point is placed below the top interface of the high velocity layer for excitation, and if controlled source is used for excitation, the shot point is placed on the ground surface for excitation. Using these two excitation methods, the obtained data will have great difference. And respectively compared with actual single shot. When well shot is used for excitation, the obtained single shot is compared with actual well shot data, and the signal-to-noise ratio of the single shot is required to be basically equivalent, and the obtained surface interference wave energy is basically equivalent. If the signal-to-noise ratio of the simulated single shot and the actual single shot is greatly different, the velocity of the near-surface model needs to be adjusted so that the signal-to-noise ratio of the simulated single shot and the actual single shot is basically equivalent. The same adjustment method is also adopted for the controlled source single shot.

[0059] After the integrated model is adjusted, the acquisition parameter analysis for the imaging requirements of Qaidam Basin is performed. CMP gathers are simulated and analyzed by setting the arrangement length and the receiver point density. The arrangement length is equal to the depth of the deepest target layer + 1000 m, for example, if the depth of the deepest target layer is 6000 m, the arrangement length is set to 7000 m. Then the receiver point trace interval is set, the receiver point trace interval = arrangement length / target fold, and the target fold is the maximum fold used in this analysis. For example, if the arrangement length is 6000 m and the target fold is 600, the receiver point trace interval = 6000 / 600 = 10 m, and the trace interval is set to 10 m. After setting the arrangement length and the trace interval, the shot point is placed at one end of the arrangement, for example, the shot point is placed below the top interface of the high velocity layer for excitation if well shot is used for excitation, and the shot point is placed on the ground surface for excitation if controlled source is used for excitation.

[0060] After simulation, the simulated record is processed by static correction to eliminate the time difference caused by surface relief. Then the record header is modified from the original single shot record header to the same CMP gather, and the record is taken as a CMP gather for stacking with different arrangement lengths and different folds. For example, the arrangement length is set to 1000-6000 m with an increment of 100 m, and the fold is set to 100-600 times with an increment of 100 times, and stacking is performed respectively. The stacked record is compared with the model to analyze which arrangement length and fold can better suppress near-surface noise and obtain reflection information with high signal-to-noise ratio.

[0061] Using this method, the acquisition parameter requirements of the geological targets in Qaidam Basin can be effectively analyzed considering the influence of near-surface noise, and the correctness of the selection of acquisition factors for the geological targets in Qaidam Basin can be effectively improved.

[0062] Finally, it should be noted that the above only describes the preferred embodiments of the present application and is not intended to limit the present application. Although the present application has been described in detail with reference to the foregoing embodiments, those skilled in the art will appreciate that modifications can be made to the technical solutions described in the foregoing embodiments, or some of the technical features thereof can be replaced equivalently, without departing from the spirit and principle of the present application. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principle of the present application should be included in the protection scope of the present application.

[0063] All that is not described in the specification is known to those skilled in the art.

Claims

1. A method for analyzing acquisition parameters to reduce the impact of secondary surface noise, characterized in that: The acquisition parameter analysis method for reducing the impact of secondary surface noise includes: Step 1: Establish a comprehensive geological model including surface, near-surface and deep layers; Step 2: Compare the simulated single shot with the actual single shot and adjust the comprehensive geological model; Step 3: Set the array length and detector density to simulate and analyze the CMP gathers; Step 4: Modify the simulated single shot trace header into a CMP trace gather; Step 5: Analyze the number of times the arrangement length is covered and collect the requirements.

2. The acquisition parameter analysis method for reducing the impact of secondary noise on the surface according to claim 1 is characterized in that: In step 1, a comprehensive geological model including surface, near-surface and deep layers is established based on the geological structure of the work area and the near-surface and surface survey conditions. The surface includes elevation fluctuation data; the near-surface includes the velocity, thickness and position information of the low-velocity layer, the deceleration layer and the high-velocity layer; the deep layer information includes the position and velocity information of each layer.

3. The acquisition parameter analysis method for reducing the impact of secondary noise on the surface according to claim 1 is characterized in that: In step 2, the single-shot simulation is compared with the actual single-shot to analyze the difference in signal-to-noise ratio between the two. Then, the geological model is adjusted until the difference in signal-to-noise ratio between the simulated single-shot and the actual single-shot is not significant. After adjusting the comprehensive model, the acquisition parameters for deep-seated imaging requirements are analyzed.

4. The acquisition parameter analysis method for reducing the impact of secondary noise on the surface according to claim 3 is characterized in that: In step 2, after the comprehensive model is established, a single shot simulation is performed and the simulation is compared with the actual single shot. The excitation can be performed by well shot, with the shot point placed below the top interface of the high-speed layer, or by controlled vibroseis, with the shot point placed on the surface. The data obtained by using these two excitation methods will be quite different, and they will be compared with the actual single shot respectively.

5. The acquisition parameter analysis method for reducing the impact of secondary noise on the surface according to claim 4 is characterized in that: In step 2, when well shot is used for excitation, the obtained single shot data is compared with the actual well shot data. The signal-to-noise ratio of the single shot is required to be basically the same, and the energy of the obtained surface interference wave is basically the same. If the signal-to-noise ratio of the simulated single shot is significantly different from that of the actual single shot, the speed of the near-surface model needs to be adjusted so that the signal-to-noise ratio of the simulated single shot is basically the same as that of the actual single shot.

6. The acquisition parameter analysis method for reducing the impact of secondary noise on the surface according to claim 5 is characterized in that: In step 2, when a single shot of a vibrator is excited, the obtained single shot is compared with the actual well shot data. The signal-to-noise ratio of the single shot is required to be basically the same, and the energy of the obtained surface interference wave is basically the same. If the signal-to-noise ratio of the simulated single shot is significantly different from that of the actual single shot, the velocity of the near-surface model needs to be adjusted so that the signal-to-noise ratio of the simulated single shot is basically the same as that of the actual single shot.

7. The acquisition parameter analysis method for reducing the impact of secondary noise on the surface according to claim 1 is characterized in that: In step 3, the array length is equal to the deepest target layer depth + 1000m. Then, the detection point spacing is set, which is array length / target coverage times. The target coverage times is the maximum coverage times used in this analysis.

8. The acquisition parameter analysis method for reducing the impact of secondary noise on the surface according to claim 7 is characterized in that: In step 3, after setting the array length and track spacing, the shot point is placed at one end of the array. If well gun excitation is used, the shot point is placed below the high-speed layer top interface for excitation, and if controllable source excitation is used, the shot point is placed on the surface for excitation. After the simulation is completed, the simulation record is statically corrected to eliminate the time difference caused by surface fluctuations.

9. The acquisition parameter analysis method for reducing the impact of secondary noise on the surface according to claim 1, characterized in that: In step 4, the record header is modified from the original single-shot record header to the same CMP gather, and the record is used as a CMP gather to perform superposition with different arrangement lengths and different coverage times.

10. The acquisition parameter analysis method for reducing the impact of secondary noise on the surface according to claim 1, characterized in that: In step 5, the stacked records are compared with the model to analyze which arrangement length and number of coverages can better suppress near-surface noise and obtain reflection information with a high signal-to-noise ratio.

11. The acquisition parameter analysis method for reducing the impact of secondary noise on the surface according to claim 10, characterized in that: In step 5, a single-channel data is obtained by stacking in step 4. This single-channel data is copied 20 times to form a "small section". Since the model stratum is flat, the stratum displayed in the copied "small section" is also flat, which can correspond well. According to the position of the shot point, the "small section" is placed at the corresponding position in the model. It is analyzed whether the position of the reflection axis in the "small section" corresponds one-to-one with the model layer and whether the signal-to-noise ratio of the reflection axis is sufficient to meet the requirements of resolving the strata. Using this method, a comparative analysis is performed to analyze at what arrangement length and how many times the "small section" is obtained to better suppress near-surface noise and obtain reflection information with a high signal-to-noise ratio.

12. A deep acquisition parameter requirement analysis system considering the influence of near-surface noise, characterized by: The deep acquisition parameter requirement analysis system considering the influence of near-surface noise adopts the acquisition parameter analysis method for weakening the influence of surface secondary noise described in any one of claims 1-11 to analyze the deep acquisition parameter requirements considering the influence of near-surface noise and select the acquisition factors of deep targets.

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