A method for predicting a gap in a three-dimensional seismic exploration profile

Abstract

The present application belongs to the technical field of oil and gas seismic exploration, and particularly relates to a three-dimensional seismic exploration profile gap prediction method. Firstly, each single-shot record is obtained by forward modeling, and each single-shot record is rearranged by CDP gather. After rearrangement, dynamic correction and dynamic correction cutting operation are performed. Then, a single-shot data cone surface with a shot point as a vertex is generated by using the seismic record after dynamic correction cutting. Then, a multi-shot data cone surface is generated by using each single-shot data cone surface. The multi-shot data cone surface is the intersection of the outer envelope surface of the maximum reflection angle seismic record of each stratum in the shot-receiver pair of the CDP bin. Finally, the size of the seismic profile gap in the forbidden shot area is determined according to the slice of the multi-shot data cone surface. Through the slice of the multi-shot data cone surface, the size of the seismic profile gap can be directly understood. This method does not require complex calculation, and compared with the method in the prior art, the calculation efficiency is obviously improved on the basis of ensuring the prediction accuracy.

Description

Technical Field

[0001] This invention belongs to the field of oil and gas seismic exploration technology, specifically relating to a method for predicting gaps in three-dimensional seismic exploration profiles. Background Technology

[0002] Seismic acquisition is the foundation and starting point of the entire seismic exploration process, ensuring the acquisition of high-quality seismic data. Acquisition design is receiving increasing attention, with the observation system being the core of this design. The seismic acquisition observation system defines the relative positions of the shot points that artificially generate seismic waves and the receiver points that receive them. In field seismic exploration, shot points are often affected by surface conditions and safety distances. For example, when blasting in areas with obstacles such as buildings, roads, bridges, and rivers, shot point offsets must be made to ensure sufficient safety distances. However, these offsets inevitably lead to uneven shot point distribution during seismic acquisition, resulting in empty shot sections and gaps in the seismic profile. To obtain high-quality seismic data, it is necessary to predict these gaps in the observation system profile to facilitate supplementary shot analysis.

[0003] Existing optimization methods are designed with an excitation-centered approach. For example, Chinese invention patent CN104570062B discloses an excitation-centered VSP observation system design method. This method designs the observation system with an excitation-centered approach, and then, based on the conventional observation system, uses a layer energy illumination method based on Gaussian ray beams for supplementary shots. Specifically, it redesigns the position and arrangement of the shot points, and then performs ray tracing calculations in the S-CRP-P direction and the P-CRP-S direction to finally obtain the distribution of shot points that need to be supplemented. The overall process is complex and computationally inefficient. Summary of the Invention

[0004] The purpose of this invention is to provide a method for predicting gaps in three-dimensional seismic exploration profiles, in order to solve the problems of complex calculation processes and low efficiency in existing technologies.

[0005] To address the aforementioned technical problems, this invention provides a method for predicting gaps in three-dimensional seismic exploration profiles, comprising the following steps:

[0006] 1) Using the observation system and the no-fire zone, generate CDP surface mesh; establish a layered velocity model and perform forward modeling to obtain individual shot records;

[0007] 2) Rearrange each single shot record according to the CDP gather, and then perform dynamic correction and dynamic correction cut-off operations; then use the seismic record after dynamic correction cut-off to generate a single shot data cone with the shot point as the vertex. The single shot data cone is the outer envelope of the seismic record of the maximum reflection angle of each stratum in the shot-receiver pair of the CDP surface element.

[0008] 3) Generate a multi-shot data cone using each single-shot data cone. The multi-shot data cone is the intersection of the outer envelopes of the maximum reflection angle seismic records of each stratum in the shot-receiver pair of the CDP surface element.

[0009] 4) Determine the size of the gap in the seismic profile of the no-fire zone based on the slices of the cone surface of the multi-shot data.

[0010] The beneficial effects of the above technical solution are as follows: This invention uses the single-shot data cone generated by forward modeling single-shot records or field single-shot records to obtain a multi-shot data cone. By slicing the multi-shot data cone, the size of the seismic profile gap can be intuitively understood. This method does not require complex calculations. Compared with the methods in the prior art, the calculation efficiency is significantly improved while ensuring the prediction accuracy.

[0011] Furthermore, the formula for calculating the apex angle of the single-shot data cone is:

[0012]

[0013] In the formula, MUTtime is the dynamic correction cut-off time; θ is the apex angle of the single-shot data cone; and offset is the shot-receiver distance.

[0014] Furthermore, the method for generating the single-shot data cone in step 2) is as follows: a single-shot data cone is generated using the seismic record after dynamic correction and shearing, and then the single-shot data cone surface is extracted from the single-shot data cone. The single-shot data cone surface is represented by the following formula:

[0015]

[0016] In the formula, t is the time value in a single shot record; Δx and Δy are the differences between the spatial coordinates of the vertex of the single shot data cone and the coordinates of the receiver point, respectively.

[0017] Furthermore, in step 3), the multi-shot data cone is generated using any of the following methods:

[0018] Method 1: Apply the representation formula of the single-shot data cone to determine whether the CDP surface element mesh is inside the single-shot data cone, and use different methods to label the internal and external regions of the single-shot data cone; determine the boundary of different labeling results at each time step, and use this boundary to generate a multi-shot data cone;

[0019] Method 2: Using the size of the basic surface element of the observation system as the scale and the number of shots (templatePS) of the observation system template as the period, slice the single-shot data cone in the longitudinal rolling direction of the observation system arrangement, and retain the data of the 1+(N-1)templatePS row of the single-shot data cone, where N is the natural index; for the data retained in the single-shot data cone, use different methods to label the internal region and the external region of the single-shot data cone; then determine the boundary of different labeling results at each time, and use the boundary to generate a multi-shot data cone.

[0020] The beneficial effects of the above technical solution are: different methods are used to generate multi-shot data cones for different situations, which is applicable to different work areas.

[0021] Furthermore, the dimensions of the seismic profile gaps include the longitudinal gap length and the transverse gap width. Within the no-fire zone, the multi-shot data cone is sliced ​​along the longitudinal and transverse rolling directions of the observation system to generate gap profiles in two directions. The longitudinal gap length and transverse gap width of the seismic profile are then determined based on the gap profiles in the two directions.

[0022] The beneficial effects of the above technical solution are: by arranging the observation system in the longitudinal and transverse rolling directions, the longitudinal gap length and transverse gap width of the seismic profile can be seen intuitively.

[0023] Furthermore, the dimensions of the seismic profile notch include the vertical notch depth of the seismic profile; the method for determining the vertical notch depth of the seismic profile is any of the following:

[0024] Method 1: Within the no-fire zone, generate a gap profile along the longitudinal rolling direction of the multi-shot data cone along the observation system arrangement, and then determine the vertical gap depth of the seismic profile based on the gap profile in that direction.

[0025] Method 2: Within the no-fire zone, slice the cone surface of multi-shot data along the lateral rolling direction of the observation system to generate a gap profile in that direction, and then determine the vertical gap depth of the seismic profile based on the gap profile in that direction.

[0026] Method 3: Within the no-fire zone, slice the cone surface of multi-shot data along the time axis to generate corresponding gap profiles, and then determine the vertical gap depth of the seismic profile based on the gap profile in this direction;

[0027] Method 4: Calculated using the following formula:

[0028]

[0029] In the formula, gap_h is the vertical gap depth of the seismic profile; T0 is the slice depth value; C is a constant; L is the minimum shot-receiver distance of the target element in the obstacle zone; V Rdenoted as , where is the replacement rate of the target layer at the obstacle; D is the dynamic correction stretching threshold.

[0030] The beneficial effect of the above technical solution is that different methods can be flexibly selected to determine the depth of the seismic profile gap according to different situations. Attached Figure Description

[0031] Figure 1 This is a flowchart of the three-dimensional seismic exploration profile gap prediction method of the present invention;

[0032] Figure 2 This invention relates to the observation system and the no-artillery zone map;

[0033] Figure 3 This is a layered model diagram of the present invention;

[0034] Figure 4 This is a single-shot recording diagram of the present invention;

[0035] Figure 5 This is a three-dimensional display diagram of a single-shot record of the present invention;

[0036] Figure 6 This is a three-dimensional display image of single-shot recording and resection of the present invention;

[0037] Figure 7 These are the transverse and horizontal slice views of the CDP path dynamic correction resection of the present invention;

[0038] Figure 8 These are the transverse, longitudinal, and horizontal slice views of the CDP path dynamic correction resection of the present invention;

[0039] Figure 9 This is a spatial relationship diagram of the conical surface function of the present invention;

[0040] Figures 10(a), 10(b), and 10(c) are respectively the single-shot data cone diagram, the single-shot data cone summation diagram, and the three-dimensional display diagram of the single-shot data cone of the present invention;

[0041] Figures 11(a), 11(b), 11(c), and 11(d) are horizontal slices of single-shot data at different times according to the present invention.

[0042] Figure 12 This is a three-dimensional display diagram of the multi-shot data cone surface of the present invention;

[0043] Figure 13 This is a planar display diagram of the shot point location and multi-shot data cone surface of the present invention;

[0044] Figure 14(a) is a diagram showing the location of the multi-shot data cone slice of the present invention;

[0045] Figure 14(b) is a profile 1 generated along the X-axis direction of the multi-shot data cone B2 according to the present invention;

[0046] Figure 14(c) is a profile 2 diagram generated along the Y-axis direction of the multi-shot data cone B2 according to the present invention. Detailed Implementation

[0047] To make the objectives, technical solutions, and advantages of the present invention clearer, the present invention will be further described in detail below with reference to the accompanying drawings and embodiments.

[0048] Method Implementation Examples:

[0049] The present invention provides a method for predicting gaps in three-dimensional seismic exploration profiles, such as... Figure 1 As shown, the specific implementation process is as follows:

[0050] Step 1: Input the observation system and the no-fire zone. Specifically: Input the boundary box coordinates of the obstacle area, and extend the obstacle boundary according to the safety distance to generate the no-fire zone. Input the shot distance SI, shot line distance SLI, receiver distance RI, receiver line distance RLI, the number of template lines of the observation system (templateXS), the number of template shots of the observation system (templatePS), and the shot coordinate file to generate the CDP mesh BIN. ij .

[0051] Step 2: Establish a layered velocity model and perform forward modeling of a single shot. Specifically: Establish a layered velocity model and perform forward modeling of a single shot record A1 for an array of slices, determining the velocities of the first layer (V1, H1), the second layer (V2, H2) to the nth layer (Vn, Hn) and the replacement velocity values.

[0052] Step 3: Perform CDP gather rearrangement, dynamic correction, and dynamic correction CDP gather cutoff to determine the apex angle of the single-shot data cone. Specifically: Rearrange single-shot record A1 using CDP gathers, perform dynamic correction on the CDP gathers, and cutoff the dynamically corrected CDP gathers using a given cutoff time and a shot-receiver offset list (MUTtime, offset). Retain the data within the apex angle of the single-shot data cone to obtain seismic record A2. The apex angle of the single-shot data cone can be determined by the relationship between the dynamic correction cutoff time and the shot-receiver offset, as expressed by the following formula:

[0053]

[0054] In the formula, MUTtime is the dynamic correction cut-off time value or the time value in the single shot record; θ is negatively correlated with the speed of dynamic correction switching, the greater the speed, the smaller the cut-off; θ is also called the apex angle of the single shot data cone in formula (2); offset is the shot-receiver distance.

[0055] Step four: Rotate the seismic record after dynamic correction and shearing by 360 degrees to generate a single-shot data cone B1-1 or B1-2; determine the effective data cone centered on the shot point. There are two methods for determining the effective data cone:

[0056] Method 1: Rotate seismic record A2 360 degrees to generate a single-shot data cone, and extract the single-shot data cone surface B1-1. The single-shot data cone surface B1-1 is a function of spatial coordinates, time values ​​in the single-shot record, and the apex angle of the single-shot data cone surface. It is the outer envelope of the maximum reflection angle seismic records of each stratum in the CDP surface element shot-receiver pair, and can be expressed by the following formula:

[0057]

[0058] In the formula, t is the time value in the single shot record; θ is the apex angle of the single shot data cone, and θ is positively correlated with the speed of dynamic correction cut-off in formula (1). The greater the speed, the greater θ is; Δx and Δy are the differences between the spatial coordinates of the apex of the single shot data cone and the coordinates of the receiver point, or the differences between the spatial coordinates of the CDP element and the coordinates of the receiver point.

[0059] Method 2: Input the CDP gathers passing the shot points on the actual production longitudinal survey line near the obstacle area, and apply formula (1) to perform dynamic correction and cut to generate seismic record A2-2. Apply formula (2) to the seismic record A2-2 to perform 360-degree rotation to generate single-shot data cone. That is, according to the difference Δx and Δy values ​​between the coordinates of the top of the single-shot data cone and the coordinates of the receiver point, and the apex angle θ of the single-shot data cone, calculate the effective data start time t of each trace and extract the single-shot data cone B1-2.

[0060] Step 5: Intersect and combine multiple single-shot data cones to generate a multi-shot data cone B2. Specifically: Place the apex of either single-shot data cone B1-1 or B1-2 at the coordinates of all shot points in the observation system. Perform outer envelope summation of the intersection surfaces of the data cones from multiple shot points. The multi-shot data cone is the intersection of the outer envelope surfaces of the maximum reflection angle seismic records of each stratum in the CDP surface alignment. There are two methods for determining this:

[0061] Method 1: Apply the time t value of formula (2) to each single-shot data cone to determine whether the surface grid in the X and Y directions is inside the single-shot data cone. Mark the inner region of the cone as 1 and the outer region of the cone as 0. Read the data 0 and 1 at different times t to generate the multi-shot data cone B2.

[0062] Method 2: First, slice the single-shot data cone with the size of the observation system's basic element BIN as the scale and the number of observation system templates PS as the period in the X direction. Keep the data of the (1+(N-1)templatePS)th row of the single-shot data cone, and the natural index N is in the range of [1,3000]. Then, apply the time t value of formula (2) to each single-shot data cone to determine whether the element grid in the X and Y directions is inside the single-shot data cone. Mark the inner region of the cone as 1 and the outer region of the cone as 0. Read the boundary of data 0 and 1 at different times t to generate the multi-shot data cone B2.

[0063] Of the two methods above, Method 1 is used to approximate the cone surface of multi-shot data and is suitable for work areas with relatively large surface velocities, similar to mountainous terrain. Method 2 is used to calculate the cone surface of multi-shot data considering the differences between each shot in the template shot of the observation system and is suitable for calculating the cone surface of data in work areas with relatively small surface velocities, similar to plains.

[0064] Step Six: Within the obstacle zone, slice the multi-shot data cone B2 along the X, Y, and Z directions to generate a notch profile, predicting the longitudinal notch length, transverse notch width, and vertical notch depth of the seismic profile. Specifically:

[0065] 1) Generate profile profile1 along the X-axis direction for the cone surface B2 of the multi-shot data to determine the gap length gap_wx1 and the gap depth gap_hx1 in the X direction at the obstacle area; where the X-axis direction is the longitudinal rolling inline direction of the observation system.

[0066] 2) Generate profile 2 along the Y-axis for the multi-shot data cone B2 to determine the gap width gap_wy1 and the gap depth gap_hy1 in the Y direction at the obstacle area; where the Y-axis direction is the crossline direction of the observation system arrangement.

[0067] 3) Slice the multi-shot data cone B2 along the Z-axis or time axis to generate slice Z1 and calculate the gap depth. Then, obtain the constant parameter C in formula (3) to approximate the gap depth. Measure the gap depth of the deepest element of multiple targets on the multi-shot data cone, then modify the gap_h formula for the gap depth of the seismic profile in the obstacle area, and obtain the constant parameter C to approximate the gap depth. It should be noted that the gap_h formula is applicable to situations where the obstacle area has a regular shape, but it is not applicable to shots with lateral offset in the crossline direction.

[0068]

[0069] In the formula, gap_h is the depth of the seismic profile gap; T0 is the slice depth value; C is a constant; L is the minimum shot-receiver distance of the target element in the obstacle zone or the size of the obstacle zone in the inline direction; V Ris the replacement rate of the target layer at the obstacle; D is the dynamic correction stretching threshold, which can be 0.125.

[0070] The following is a specific example to further illustrate the implementation process of the above method.

[0071] Step 1: Input the observation system and the no-fire zone. Input the boundary coordinates of the obstacle zone, and extend the obstacle boundary according to the safe distance to generate the no-fire zone. Figure 2 As shown, the input shot distance SI is 50m, shot line distance SLI is 400m, receiver distance RI is 25m, receiver line distance RLI is 200m, the number of template lines in the observation system (templateXS) is 32, the number of shots in the observation system (templatePS) is 4, and the shot coordinate file is used to generate the CDP mesh BIN. ij In this context, i and j are natural serial numbers. The grid size of the BIN dimension is 12.5m * 25m. The vertical direction along the receiving line is represented by X or inline, and numbered as INL line number. The direction perpendicular to the receiving line is represented by Y or crossline, and numbered as CRL number.

[0072] Step 2: Establish a layered velocity model and perform forward modeling of a single shot. Establish a layered velocity model (e.g., Figure 3 As shown in Table 1, the model size is 18500m in the X direction, 8000m in the Y direction, and 6500m in the Z direction. The single-shot record A1 of one array is shown (e.g., ...). Figure 4 As shown), determine the velocities of the first layer (V1, H1), the second layer (V2, H2), and up to the nth layer (Vn, Hn), where (V1, H1) is (1000, 250), and up to (V6, H6) is (5000, 6500). Figure 3 As shown in the figure, the replacement speed is 2000 m / s.

[0073] Table 1

[0074]

[0075]

[0076] Step 3: CDP gather rearrangement and dynamic correction cut-off to determine the apex angle of the single-shot cone. For single-shot record A1 ( Figures 5 to 6 (As shown) Seismic records A2 are obtained by rearranging the CDP gathers according to their dynamic corrections and removing the dynamic corrections from the CDP gathers. Figures 7 to 8 As shown. Applying formula (1) to obtain the apex angle of the single shot cone, the control point (X, T) of the dynamic correction cutoff distance-time parameter, or (offset, MUTtime), is shown in the dynamic correction cutoff XT table (as shown in Table 2). The apex angle θ of the single shot cone in formula (2) is 53.13°.

[0077] Table 2

[0078] Floor number Distance X(s) Time T (ms) 1 100 200 2 200 400 3 300 600 4 400 800 5 500 1000 6 600 1200 7 700 1400 8 800 1600 9 900 1800

[0079] Step four: After dynamic correction and shearing, the seismic record is rotated 360 degrees to generate single-shot data cone data B1-1 or B1-2; the effective data cone is determined with the shot point as the center. There are two ways to determine the effective data cone; the first method is used here, namely: rotating the seismic record A2 360 degrees to generate a single-shot data cone. Figure 9 The cone surface PMNK shown is used to obtain the t value by applying formula (2) with the coordinates of point N relative to the cone apex as (Δx, Δy), and the single-shot data cone surface B1-1 is generated.

[0080] Step 5: Combine the intersection surfaces of multiple single-shot data cones to generate multi-shot data cone B2. Place the cone apex of single-shot data cone B1-1 or B1-2 at the coordinate positions of all shot points in the observation system, and combine the outer envelopes of the intersection surfaces of the data cones of multiple shot points. The multi-shot data cone is the intersection of the outer envelope surfaces of the maximum reflection angle seismic records of each stratum in the CDP surface alignment. It can be determined using the following two methods:

[0081] Method 1: Apply formula (2) to each single-shot data cone to determine whether the surface element mesh in the X and Y directions is inside the single-shot data cone. Mark the inner region of the cone as 1 and the outer region of the cone as 0, as shown in Figure 10(a). Moreover, the triangle shown in Figure 10(b) is the region marked as 0 using two single-shot data cones. Figure 10(c) is the three-dimensional display of the corresponding single-shot data cone. Then read the single-shot cones at different times t1, t2 to tn, as shown in Figure 10(a). Figures 11(a) to 11(c) As shown in Figure 11(a), the cone slice at time t1 is a circular blue area labeled 1; Figure 11(b) shows the cone slice at time t2 as a circular yellow area labeled 1; and Figure 11(c) shows the cone slice at time tn as a circular cyan area labeled 1. The multi-shot data cone slice B2 is generated by recursively finding the boundary line between 0 and 1 in the multi-shot cone slice data. The final result is as follows: Figure 12 As shown.

[0082] Method 2: First, the single-shot data cone is scaled to 12.5*25 meters using the size of the observation system's base element BIN. For each single-shot data cone, formula (2) is applied to determine whether the X and Y direction element grids are within the single-shot data cone. Then, the X direction is sliced ​​with a period of 4 for the observation system's template shot count (templatePS). The data of the (1+(N-1)templatePS) row of the single-shot data cone is retained, that is, the elements in the 1st row (counted from the top of the single-shot data cone) and the 5th and 11th rows are marked as 1, as shown in Figure 11(d). The colored areas are marked as 1. Figure 11(d) is a further slice of Figure 11(c) with a period of 4 shots. The elements in the 2nd, 3rd, and 4th rows are marked as 0. The uncolored elements in Figure 11(d) are marked as 0. Then, the boundary lines of data 0 and 1 at different times t are read to generate the multi-shot data cone B2. The shot point location and the multi-shot data cone planar display diagram are shown below. Figure 13 As shown.

[0083] Of the two methods above, Method 1 is used to approximate the cone surface of multi-shot data and is applicable to work areas with relatively large surface velocities, similar to mountainous terrain. Method 2 is used to calculate the cone surface of multi-shot data considering the differences between each shot in the template shot of the observation system and is applicable to the calculation of the cone surface of data in work areas with relatively small surface velocities, similar to plains.

[0084] Step 6: Within the obstacle zone, slice the multi-shot data cone B2 along the X, Y, and Z directions to generate a notch profile, as shown in Figure 14(a). Predict the longitudinal notch length, transverse notch width, and vertical notch depth of the seismic profile. Specifically:

[0085] 1) Generate profile profile1 along the X-axis direction for the multi-shot data cone B2 to determine the gap length gap_wx1 in the obstacle area as 950m and the gap depth gap_hx1 in the X direction as 1160ms, as shown in Figure 14(b); where the X-axis direction is the longitudinal rolling inline direction of the observation system.

[0086] 2) Generate profile profile2 along the Y-axis direction for the multi-shot data cone B2 to determine the gap width gap_wy1 in the obstacle area as 600m and the gap depth gap_hy1 in the Y direction as 1180ms, as shown in Figure 14(c); where the Y-axis direction is the crossline direction of the observation system arrangement.

[0087] 3) Slice the multi-shot data cone B2 along the Z-axis to generate slice Z1 and calculate the gap depth. Then, obtain the constant parameter C in formula (3) to approximate the gap depth. Measure the gap depth of the deepest surface element of multiple targets on the multi-shot data cone. Then, correct the gap_h formula for the gap depth of the seismic profile in the obstacle area and obtain the constant parameter C to approximate the gap depth. Moreover, the gap_h formula is applicable to situations where the obstacle area has a regular shape, but it is not applicable to shots with lateral offset in the crossline direction. In formula (3), T0 is the slice depth value of 1160ms, and L is the minimum shot-receiver distance of the target surface element in the obstacle area or the size of the obstacle area in the inline direction of 600m. Replacement velocity V R With a speed of 2000 m / s and a value of D of 0.125, the value of C is 0.96. After obtaining the value of C, the depth of the seismic profile gap can be estimated by measuring the length and width of the obstacle zone on the plane.

Claims

1. A method for predicting gaps in three-dimensional seismic exploration profiles, characterized in that, include: 1) Generate CDP surface mesh using the observation system and no-artillery zone; A layered velocity model was established and forward modeling was performed to obtain individual shot records; 2) Rearrange each shot record according to the CDP gather, and then perform dynamic correction and dynamic correction cut-off operations; then use the seismic record after dynamic correction cut-off to generate a single shot data cone with the shot point as the vertex. The single shot data cone is the outer envelope of the maximum reflection angle seismic record of each stratum in the shot-receiver pair of the CDP surface element. 3) Generate a multi-shot data cone using each single-shot data cone and any of the following methods. The multi-shot data cone is the intersection of the outer envelopes of the maximum reflection angle seismic records of each stratum in the CDP element shot-receiver pair: Method 1: Apply the representation formula of the single-shot data cone to determine whether the CDP surface element mesh is inside the single-shot data cone, and use different methods to label the internal and external regions of the single-shot data cone; determine the boundary of different labeling results at each time step, and use this boundary to generate a multi-shot data cone; Method 2: Using the size of the basic surface element of the observation system as the scale and the number of shots (templatePS) of the observation system template as the period, slice the single-shot data cone in the longitudinal rolling direction of the observation system arrangement, retaining the data of the 1+(N-1)templatePS row of the single-shot data cone, where N is the natural index; for the data retained in the single-shot data cone, use different methods to label the internal region and the external region of the single-shot data cone; then determine the boundary of different labeling results at each time step, and use this boundary to generate a multi-shot data cone; 4) Determine the longitudinal gap length, transverse gap width, and vertical gap depth of the seismic profile in the no-fire zone based on the slices of the cone surface of the multi-shot data.

2. The method for predicting gaps in three-dimensional seismic exploration profiles according to claim 1, characterized in that, The formula for calculating the apex angle of the cone surface in single-shot data is: In the formula, MUTtime is the dynamic correction cut-off time; θ is the apex angle of the single-shot data cone; and offset is the shot-receiver distance.

3. The method for predicting gaps in three-dimensional seismic exploration profiles according to claim 2, characterized in that, The method for generating the single-shot data cone in step 2) is as follows: A single-shot data cone is generated using the seismic record after dynamic correction and shearing, and then the single-shot data cone surface is extracted from the single-shot data cone. The single-shot data cone surface is represented by the following formula: In the formula, t is the time value in a single shot record; Δx and Δy are the differences between the spatial coordinates of the vertex of the single shot data cone and the coordinates of the receiver point, respectively.

4. The method for predicting gaps in three-dimensional seismic exploration profiles according to any one of claims 1 to 3, characterized in that, Within the no-fire zone, slices are taken from the cone of multi-shot data along the longitudinal and transverse rolling directions of the observation system to generate two-directional gap profiles. Then, the longitudinal gap length and transverse gap width of the seismic profile are determined based on the two-directional gap profiles.

5. The method for predicting gaps in three-dimensional seismic exploration profiles according to any one of claims 1 to 3, characterized in that, The method for determining the vertical notch depth of a seismic profile is any of the following: Method 1: Within the no-fire zone, generate a gap profile along the longitudinal rolling direction of the multi-shot data cone along the observation system arrangement, and then determine the vertical gap depth of the seismic profile based on the gap profile in that direction. Method 2: Within the no-fire zone, slice the cone surface of multi-shot data along the lateral rolling direction of the observation system to generate a gap profile in that direction, and then determine the vertical gap depth of the seismic profile based on the gap profile in that direction. Method 3: Within the no-fire zone, slice the cone surface of multi-shot data along the time axis to generate corresponding gap profiles, and then determine the vertical gap depth of the seismic profile based on the gap profile in this direction; Method 4: Calculated using the following formula: In the formula, gap_h is the vertical gap depth of the seismic profile; T0 is the slice depth value; C is a constant; L is the minimum shot-receiver distance of the target element in the obstacle zone; V R denoted as , where is the replacement rate of the target layer at the obstacle; D is the dynamic correction stretching threshold.

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