Seismic data denoising method, storage medium and computer equipment

Abstract

The present invention discloses a seismic data denoising method, a storage medium and a computer device. The method comprises: estimating the dip angle of a common angle data body in seismic data; performing vector median filtering on the dip angle of the common angle data body to perform a first denoising on the common angle data body; performing vector median filtering on the common angle data body after the first denoising along the dip angle to perform a second denoising on the common angle data body, and being able to carry out vector median filtering along the direction of the event axis, which can both denoise and retain effective signals and maintain the continuity of the seismic event axis, thereby improving the quality of seismic data.

Description

Technical Field

[0001] The present invention belongs to the technical field of oil and gas geophysical applications, and in particular relates to a seismic data denoising method, a storage medium and a computer device. Background Art

[0002] Shale oil refers to self-generated, self-reserved, and continuously distributed oil accumulations in the pores, cracks, and interlayers of sandstone, carbonate rock, and other dark mud shale with extremely low permeability. In the past decade, due to the advancement of drilling and fracturing transformation technology, mud shale is no longer just considered as a traditional source rock and cap rock, but also an important reservoir of oil and gas resources. In particular, the development of shale oil and gas can be regarded as a new fossil energy revolution. China's shale resources are generally distributed in fault basins. They are highly heterogeneous continental deposits. Their oil and gas maturity is not high, the flow performance is poor, and they are generally difficult to exploit. Due to the complexity of the detection target, the quality of pre-stack seismic data collected for shale oil is poor, and the signal-to-noise ratio is very low, which is not conducive to the interpretation and identification of shale oil target layers. In addition, due to the sedimentary characteristics, the seismic phase axis of shale oil fluctuates greatly. In the process of improving the quality of seismic data, it is necessary to consider the trend information of the phase axis.

[0003] Traditional median filtering is scalar median filtering, that is, the middle value is selected from a series of values ​​as the output of the filter. Vector median filtering is an ideal extension of scalar median filtering. First, the above "series of values" becomes "a series of vectors". Second, the output of the filter is a median vector, not the "middle value" of the traditional median filter output. Vector median filtering is similar to scalar median filtering, both of which smooth the data by taking the median of the sub-datasets within the time window. The vector median filtering method does not find the median of the sub-datasets within each window, but finds the median vector. According to the "sum of distances" minimization criterion, the sum of the distances between the median vector and all other vectors in the window is the smallest. It should be noted that if more than one vector satisfies the "sum of distances minimization criterion" at the same time, additional constraints need to be introduced to eliminate this ambiguity. For example, the vector with the largest correlation value with the vector at the center of the input vector window can be selected as the median vector. For seismic data with relatively flat event axes, the conventional vector median filtering method can remove noise. However, for seismic data with rhythmic structures and undulating large strata such as complex shale oil exploration areas, the conventional vector median filtering denoising method will suppress effective signals while denoising, destroy the continuity of the event axes, and lose effective seismic signal energy, which is not conducive to the further processing and interpretation of seismic data.

[0004] There is an urgent need for a seismic data denoising method, storage medium and computer equipment. Summary of the invention

[0005] In view of the above problems, the present invention provides a seismic data denoising method, a storage medium and a computer device.

[0006] In a first aspect, the present invention provides a method for denoising seismic data, comprising the following steps:

[0007] Estimate the dip angle of the co-angle data volume in seismic data;

[0008] Performing vector median filtering on the inclination of the common angle data volume to perform first denoising on the common angle data volume;

[0009] The common angle data volume after the first denoising is subjected to vector median filtering along the inclination angle to perform secondary denoising on the common angle data volume.

[0010] According to an embodiment of the present invention, preferably, the common-angle data volume is a data volume with the same incident angle in the seismic data.

[0011] According to an embodiment of the present invention, preferably, estimating the dip angle of a common angle data volume in the seismic data comprises:

[0012] The dip angles in the x-direction and y-direction of the common angle data volume in the seismic data are estimated by using any one of the local dip angle calculation methods based on plane wave decomposition, the direct dip angle calculation method, the local dip angle calculation method based on Hilbert transform and the local dip angle calculation method based on time-distance curve relationship.

[0013] According to an embodiment of the present invention, preferably, performing vector median filtering on the inclination angle of the common angle data volume includes:

[0014] Vector median filtering is performed on the dip angles in the x direction and the dip angles in the y direction of the common angle data volume in the seismic data, and the filtered dip angles in the x direction and the y direction are used as the common angle data volume after the first denoising.

[0015] According to an embodiment of the present invention, preferably, vector median filtering is performed on the dip angles in the x direction and the dip angles in the y direction of the common angle data volume in the seismic data, respectively, and the dip angles in the x direction and the dip angles in the y direction after filtering are used as the common angle data volume after the first denoising, including:

[0016] The dip angle in the x direction and the dip angle in the y direction of the common angle data volume in the seismic data are used as the original dip vector in the x direction and the original dip vector in the y direction respectively;

[0017] A plurality of x-direction vector groups are formed with each inclination angle of the x-direction inclination original vector as the center;

[0018] Selecting an x-direction median vector in each x-direction vector group, wherein the sum of distances between the x-direction median vector and all other vectors in the x-direction vector group in which the x-direction median vector is located is the smallest;

[0019] The x-direction median vector of the multiple x-direction vector groups is the inclination angle in the x-direction after filtering;

[0020] A plurality of y-direction vector groups are formed with each inclination angle of the y-direction inclination original vector as the center;

[0021] Selecting a median vector in the y direction from each y direction vector group, wherein the sum of distances between the median vector in the y direction and all other vectors in the y direction vector group in which the median vector in the y direction belongs is the smallest;

[0022] The y-direction median vector of the plurality of y-direction vector groups is the inclination angle in the y-direction after filtering;

[0023] The filtered inclination angle in the x direction and the filtered inclination angle in the y direction are used as the common angle data volume after the first denoising.

[0024] According to an embodiment of the present invention, preferably, performing vector median filtering on the common angle data volume after the first denoising along the inclination angle includes:

[0025] Calculate the time parameter of the common angle data volume according to the filtered inclination angle in the x direction and the inclination angle in the y direction;

[0026] The time parameter of the common angle data volume is used as the original time vector;

[0027] A plurality of time vector groups are formed with each time of the original time vector as the center;

[0028] Selecting a time median vector in each time vector group, wherein the sum of distances between the time median vector and all other vectors in the time vector group to which it belongs is the smallest;

[0029] The time median vectors of the multiple time vector groups are the time parameters of the filtered common angle data volume.

[0030] According to an embodiment of the present invention, preferably, the step of calculating the time parameter of the common angle data volume according to the filtered inclination angle in the x direction and the inclination angle in the y direction comprises:

[0031] Calculate the true inclination angle according to the filtered inclination angle in the x direction and the inclination angle in the y direction;

[0032] The time parameters of the common angle data volume are calculated based on the true inclination.

[0033] According to an embodiment of the present invention, preferably, the seismic data is pre-stack common reflection point gather data.

[0034] In a second aspect, the present invention provides a storage medium having a computer program stored thereon, which implements the steps of the above-mentioned seismic data denoising method when executed by a processor.

[0035] In a third aspect, the present invention provides a computer device comprising a memory and a processor, wherein the memory stores a computer program, and when the computer program is executed by the processor, the steps of the above-mentioned seismic data denoising method are implemented.

[0036] Compared with the prior art, one or more embodiments of the above scheme may have the following advantages or beneficial effects:

[0037] The seismic data denoising method of the present invention is applied to estimate the inclination of the common angle data body in the seismic data; vector median filtering is performed on the inclination of the common angle data body to perform the first denoising on the common angle data body; vector median filtering is performed on the common angle data body after the first denoising along the inclination to perform the second denoising on the common angle data body, and vector median filtering can be performed along the direction of the event axis, which can not only denoise and retain the effective signal, but also maintain the continuity of the seismic event axis, thereby improving the quality of seismic data.

[0038] Other features and advantages of the present invention will be described in the following description, and partly become apparent from the description, or understood by practicing the present invention. The purpose and other advantages of the present invention can be realized and obtained by the structures particularly pointed out in the description, claims and drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0039] The accompanying drawings are used to provide a further understanding of the present invention and constitute a part of the specification. Together with the embodiments of the present invention, they are used to explain the present invention and do not constitute a limitation of the present invention. In the accompanying drawings:

[0040] Figure 1 A flow chart of a method for denoising seismic data according to an embodiment of the present invention is shown;

[0041] Figure 2 A flow chart of a seismic data denoising method according to a second embodiment of the present invention is shown;

[0042] Figure 3 A schematic diagram of extracting a data volume with the same incident angle from a pre-stack CRP gather collected in a shale oil target exploration area in Qianjiang Sag in accordance with the third embodiment of the present invention is shown;

[0043] FIG4( a ) shows the result of filtering and denoising the prestack CRP gathers collected from the shale oil target exploration area in the Qianjiang Sag by using the traditional vector median filtering method in the third embodiment of the present invention;

[0044] FIG4( b ) shows the noise filtered out by filtering the prestack CRP gathers collected from the shale oil target exploration area in the Qianjiang Sag by the traditional vector median filtering method in the third embodiment of the present invention;

[0045] FIG5(a) shows the result of filtering and denoising the prestack CRP gathers collected from the shale oil target exploration area in Qianjiang Sag by the seismic data denoising method of this embodiment according to the third embodiment of the present invention;

[0046] FIG5( b ) shows the noise filtered out by filtering the prestack CRP gathers collected from the shale oil target exploration area in the Qianjiang Sag using the seismic data denoising method of this embodiment according to the third embodiment of the present invention. DETAILED DESCRIPTION

[0047] The following will describe the implementation methods of the present invention in detail with reference to the accompanying drawings and embodiments, so that the implementation process of how the present invention applies technical means to solve technical problems and achieve technical effects can be fully understood and implemented accordingly. It should be noted that as long as there is no conflict, the various embodiments of the present invention and the various features in the embodiments can be combined with each other, and the technical solutions formed are all within the protection scope of the present invention.

[0048] Embodiment 1

[0049] In order to solve the above technical problems existing in the prior art, an embodiment of the present invention provides a seismic data denoising method.

[0050] Reference Figure 1 The seismic data denoising method of this embodiment includes the following steps:

[0051] S11, estimating the inclination of a common angle data volume in the seismic data, wherein the common angle data volume is a data volume with the same incident angle in the seismic data;

[0052] S12, performing vector median filtering on the inclination of the common angle data volume to perform first denoising on the common angle data volume;

[0053] S13, performing vector median filtering on the common angle data volume after the first denoising along the inclination angle, so as to perform secondary denoising on the common angle data volume.

[0054] In this embodiment, in step S11, the seismic data is pre-stack common reflection point gather data.

[0055] The seismic data denoising method of this embodiment performs vector median filtering based on the structural dip angle guidance, effectively suppresses noise while retaining seismic signals, improves the signal-to-noise ratio of seismic data, and provides high-quality seismic data for seismic processing and interpretation of complex shale oil and gas exploration target areas.

[0056] Embodiment 2

[0057] In order to solve the above technical problems existing in the prior art, the embodiment of the present invention provides a seismic data denoising method based on the first embodiment, wherein the present embodiment improves steps S11, S12 and S13 of the first embodiment.

[0058] Reference Figure 2 The seismic data denoising method of this embodiment includes the following steps:

[0059] S21, estimating the dip angles in the x-direction and the y-direction of the common angle data volume in the seismic data by using any one of a local dip angle calculation method based on plane wave decomposition, a direct dip angle calculation method, a local dip angle calculation method based on Hilbert transform, and a local dip angle calculation method based on a time-distance curve relationship;

[0060] S22, respectively performing vector median filtering on the dip angle in the x direction and the dip angle in the y direction of the common angle data volume in the seismic data, and using the dip angle in the x direction and the dip angle in the y direction after filtering as the common angle data volume after the first denoising;

[0061] S231, calculating the time parameter of the common angle data volume according to the filtered inclination angle in the x direction and the inclination angle in the y direction;

[0062] S232, using the time parameter of the common angle data volume as the original time vector;

[0063] S233, forming a plurality of time vector groups with each time of the original time vector as the center;

[0064] S234, selecting a time median vector in each time vector group, wherein the sum of distances between the time median vector and all other vectors in the time vector group to which it belongs is the smallest;

[0065] S235, the time median vectors of the multiple time vector groups are the time parameters of the filtered common-angle data volume.

[0066] In this embodiment, in step S22, vector median filtering is performed on the dip angles in the x direction and the dip angles in the y direction of the common angle data volume in the seismic data, and the dip angles in the x direction and the dip angles in the y direction after filtering are used as the common angle data volume after the first denoising, including:

[0067] The dip angle in the x direction and the dip angle in the y direction of the common angle data volume in the seismic data are used as the original dip vector in the x direction and the original dip vector in the y direction respectively;

[0068] A plurality of x-direction vector groups are formed with each inclination angle of the x-direction inclination original vector as the center;

[0069] Selecting an x-direction median vector in each x-direction vector group, wherein the sum of distances between the x-direction median vector and all other vectors in the x-direction vector group in which the x-direction median vector is located is the smallest;

[0070] The x-direction median vector of the multiple x-direction vector groups is the inclination angle in the x-direction after filtering;

[0071] A plurality of y-direction vector groups are formed with each inclination angle of the y-direction inclination original vector as the center;

[0072] Selecting a median vector in the y direction from each y direction vector group, wherein the sum of distances between the median vector in the y direction and all other vectors in the y direction vector group in which the median vector in the y direction belongs is the smallest;

[0073] The y-direction median vector of the plurality of y-direction vector groups is the inclination angle in the y-direction after filtering;

[0074] The filtered inclination angle in the x direction and the filtered inclination angle in the y direction are used as the common angle data volume after the first denoising.

[0075] In this embodiment, in step S231, calculating the time parameter of the common angle data volume according to the filtered inclination angle in the x direction and the inclination angle in the y direction includes:

[0076] The true inclination is calculated from the filtered inclination in the x-direction and the inclination in the y-direction based on the following expression:

[0077]

[0078] Among them, θ is the true inclination, θx is the inclination in the x direction after filtering, and θy is the inclination in the y direction.

[0079] The time parameters of the common angle data volume are calculated from the true inclination based on the following expression:

[0080]

[0081] Among them, t is the time parameter of the common angle data volume, h is the burial depth, x is the offset, θ is the true inclination, and v is the wave velocity.

[0082] The seismic data denoising method of this embodiment simultaneously considers the influence of the direction of the seismic phase axis during the seismic denoising process, combines the seismic data dip angle with the vector median filtering denoising method, performs vector median filtering based on the dip angle guidance of the structure, effectively suppresses random noise, and improves the signal-to-noise ratio of the seismic data.

[0083] The seismic data denoising method of this embodiment uses the dip angle constructed in the x and y directions to calculate the time t(x, y) passing through any point (x, y). This method synchronously integrates the dip angle information in the x and y directions, which is conducive to the accurate selection of vectors within the vector median filter window and the realization of high-precision vector median filtering of data along the dip angle direction.

[0084] Embodiment 3

[0085] In order to solve the above-mentioned technical problems existing in the prior art, an embodiment of the present invention provides a seismic data denoising method based on Example 2, wherein the method of the embodiment of the present invention is applied to a denoising test of a pre-stack CRP data set collected in the shale oil target exploration area of ​​Qianjiang Depression.

[0086] The seismic data denoising method of this embodiment includes:

[0087] (1) Estimate the inclination angles in the x and y directions of the common angle data volume;

[0088] In this embodiment, the common angle data volume is a data volume with the same incident angle extracted from the pre-stack CRP gathers collected in the shale oil target exploration area of ​​Qianjiang Sag, such as Figure 3 shown.

[0089] In this embodiment, the methods for estimating the inclination angles in the x and y directions of the common angle data body include a direct calculation method, a local inclination angle calculation method based on Hilbert transform, a local inclination angle calculation method based on plane wave decomposition, a local inclination angle calculation method based on the time-distance curve relationship, and a local inclination angle calculation method based on plane wave decomposition, among which the local inclination angle calculation method based on plane wave decomposition is preferred.

[0090] (2) Perform vector median filtering on the estimated inclination angle;

[0091] In this embodiment, vector median filtering is performed on the dip angles in the x direction and the dip angles in the y direction of the common angle data volume in the seismic data, and the filtered dip angles in the x direction and the y direction are used as the common angle data volume after the first denoising.

[0092] In this embodiment, vector median filtering is performed on the dip angle in the x direction of the common angle data volume in the seismic data, including:

[0093] The dip angle in the x direction of the common angle data volume in the seismic data is used as the original dip angle vector in the x direction;

[0094] A plurality of x-direction vector groups are formed with each inclination angle of the x-direction inclination original vector as the center;

[0095] Selecting an x-direction median vector in each x-direction vector group, wherein the sum of distances between the x-direction median vector and all other vectors in the x-direction vector group in which the x-direction median vector is located is the smallest;

[0096] The x-direction median vector of the multiple x-direction vector groups is the inclination angle in the x-direction after filtering;

[0097] The filtered inclination angle in the x direction is used as the common angle data volume after the first denoising.

[0098] In this embodiment, vector median filtering is performed on the dip angle in the y direction of the common angle data volume in the seismic data.

[0099] The dip angle in the y direction of the common angle data volume in the seismic data is used as the original dip angle vector in the y direction;

[0100] A plurality of y-direction vector groups are formed with each inclination angle of the y-direction inclination original vector as the center;

[0101] Selecting a median vector in the y direction from each y direction vector group, wherein the sum of distances between the median vector in the y direction and all other vectors in the y direction vector group in which the median vector in the y direction belongs is the smallest;

[0102] The y-direction median vector of the plurality of y-direction vector groups is the inclination angle in the y-direction after filtering;

[0103] The filtered inclination angle in the y direction is used as the common angle data volume after the first denoising.

[0104] (3) Perform vector median filtering on the common angle data volume along the inclination angle.

[0105] In this embodiment, the time parameter of the common angle data volume calculated according to the filtered inclination angle in the x direction and the inclination angle in the y direction is used as the filtering object.

[0106] In this embodiment, filtering the time parameters of the common angle data volume includes:

[0107] The time parameter of the common angle data volume is used as the original time vector;

[0108] A plurality of time vector groups are formed with each time of the original time vector as the center;

[0109] Selecting a time median vector in each time vector group, wherein the sum of distances between the time median vector and all other vectors in the time vector group to which it belongs is the smallest;

[0110] The time median vectors of the multiple time vector groups are the time parameters of the filtered common angle data volume.

[0111] In this embodiment, the time parameters of the common angle data volume calculated according to the filtered inclination angle in the x direction and the inclination angle in the y direction include:

[0112] The true inclination is calculated from the filtered inclination in the x-direction and the inclination in the y-direction based on the following expression:

[0113]

[0114] Among them, θ is the true inclination, θx is the inclination in the x direction after filtering, and θy is the inclination in the y direction.

[0115] The time parameters of the common angle data volume are calculated from the true inclination based on the following expression:

[0116]

[0117] Among them, t is the time parameter of the common angle data volume, h is the burial depth, x is the offset, θ is the true inclination, and v is the wave velocity.

[0118] This embodiment carries out denoising test on the pre-stack CRP data set collected in the target exploration area of ​​shale oil in Qianjiang Sag. The following embodiment takes the profile of line number 950 as an example to show the denoising result of the seismic data denoising method of this embodiment, and compares it with the denoising result of the traditional vector median filtering method. Figure 4 (a) is the result of filtering and denoising the pre-stack CRP data set collected in the target exploration area of ​​shale oil in Qianjiang Sag by the traditional vector median filtering method, and Figure 4 (b) is the noise filtered out by filtering the pre-stack CRP data set collected in the target exploration area of ​​shale oil in Qianjiang Sag by the traditional vector median filtering method; Figure 5 (a) is the result of filtering and denoising the pre-stack CRP data set collected in the target exploration area of ​​shale oil in Qianjiang Sag by the seismic data denoising method of this embodiment, and Figure 5 (b) is the noise filtered out by filtering the pre-stack CRP data set collected in the target exploration area of ​​shale oil in Qianjiang Sag by the seismic data denoising method of this embodiment.

[0119] By comparison, it can be seen that after the seismic data denoising method of this embodiment performs vector median filtering, the random noise in the seismic data is suppressed, the effective signal is retained, and the signal-to-noise ratio of the seismic data is significantly improved. Therefore, the seismic data denoising method of this embodiment not only effectively filters out noise information and improves the signal-to-noise ratio, but also maintains the integrity of the event axis, providing high-quality seismic data for seismic processing and interpretation of complex shale oil and gas exploration target areas.

[0120] The seismic data denoising method of this embodiment is stable and easy to parallelize, is suitable for denoising large volumes of seismic data in complex oil and gas exploration target areas, and has the potential for application in geophysical production.

[0121] Embodiment 4

[0122] In order to solve the above technical problems existing in the prior art, an embodiment of the present invention further provides a storage medium.

[0123] In one embodiment, the storage medium of this embodiment stores a computer program thereon, and when the program is executed by a processor, the following seismic data denoising method is implemented:

[0124] S11, estimating the inclination of a common angle data volume in the seismic data, wherein the common angle data volume is a data volume with the same incident angle in the seismic data;

[0125] S12, performing vector median filtering on the inclination of the common angle data volume to perform first denoising on the common angle data volume;

[0126] S13, performing vector median filtering on the common angle data volume after the first denoising along the inclination angle, so as to perform secondary denoising on the common angle data volume.

[0127] In another embodiment, the storage medium of this embodiment stores a computer program thereon, and when the program is executed by a processor, the following seismic data denoising method is implemented:

[0128] S21, estimating the dip angles in the x-direction and the y-direction of the common angle data volume in the seismic data by using any one of a local dip angle calculation method based on plane wave decomposition, a direct dip angle calculation method, a local dip angle calculation method based on Hilbert transform, and a local dip angle calculation method based on a time-distance curve relationship;

[0129] S22, respectively performing vector median filtering on the dip angle in the x direction and the dip angle in the y direction of the common angle data volume in the seismic data, and using the dip angle in the x direction and the dip angle in the y direction after filtering as the common angle data volume after the first denoising;

[0130] S231, calculating the time parameter of the common angle data volume according to the filtered inclination angle in the x direction and the inclination angle in the y direction;

[0131] S232, using the time parameter of the common angle data volume as the original time vector;

[0132] S233, forming a plurality of time vector groups with each time of the original time vector as the center;

[0133] S234, selecting a time median vector in each time vector group, wherein the sum of distances between the time median vector and all other vectors in the time vector group to which it belongs is the smallest;

[0134] S235: The time median vectors of the multiple time vector groups are the time parameters of the filtered common-angle data volume.

[0135] In this embodiment, in step S22, vector median filtering is performed on the dip angles in the x direction and the dip angles in the y direction of the common angle data volume in the seismic data, and the dip angles in the x direction and the dip angles in the y direction after filtering are used as the common angle data volume after the first denoising, including:

[0136] The dip angle in the x direction and the dip angle in the y direction of the common angle data volume in the seismic data are used as the original dip vector in the x direction and the original dip vector in the y direction respectively;

[0137] A plurality of x-direction vector groups are formed with each inclination angle of the x-direction inclination original vector as the center;

[0138] Selecting an x-direction median vector in each x-direction vector group, wherein the sum of distances between the x-direction median vector and all other vectors in the x-direction vector group in which the x-direction median vector is located is the smallest;

[0139] The x-direction median vector of the multiple x-direction vector groups is the inclination angle in the x-direction after filtering;

[0140] A plurality of y-direction vector groups are formed with each inclination angle of the y-direction inclination original vector as the center;

[0141] Selecting a median vector in the y direction from each y direction vector group, wherein the sum of distances between the median vector in the y direction and all other vectors in the y direction vector group in which the median vector in the y direction belongs is the smallest;

[0142] The y-direction median vector of the plurality of y-direction vector groups is the inclination angle in the y-direction after filtering;

[0143] The filtered inclination angle in the x direction and the filtered inclination angle in the y direction are used as the common angle data volume after the first denoising.

[0144] In this embodiment, in step S231, calculating the time parameter of the common angle data volume according to the filtered inclination angle in the x direction and the inclination angle in the y direction includes:

[0145] The true inclination is calculated from the filtered inclination in the x-direction and the inclination in the y-direction based on the following expression:

[0146]

[0147] Among them, θ is the true inclination, θx is the inclination in the x direction after filtering, and θy is the inclination in the y direction.

[0148] The time parameters of the common angle data volume are calculated from the true inclination based on the following expression:

[0149]

[0150] Among them, t is the time parameter of the common angle data volume, h is the burial depth, x is the offset, θ is the true inclination, and v is the wave velocity.

[0151] In another embodiment, the storage medium of this embodiment stores a computer program thereon, and when the program is executed by a processor, the following seismic data denoising method is implemented:

[0152] (1) Estimate the inclination angles in the x and y directions of the common angle data volume;

[0153] In this embodiment, the common angle data volume is a data volume with the same incident angle extracted from the pre-stack CRP gathers collected in the shale oil target exploration area of ​​Qianjiang Sag, such as Figure 3 shown.

[0154] In this embodiment, the methods for estimating the inclination angles in the x and y directions of the common angle data body include a direct calculation method, a local inclination angle calculation method based on Hilbert transform, a local inclination angle calculation method based on plane wave decomposition, a local inclination angle calculation method based on the time-distance curve relationship, and a local inclination angle calculation method based on plane wave decomposition, among which the local inclination angle calculation method based on plane wave decomposition is preferred.

[0155] (2) Perform vector median filtering on the estimated inclination angle;

[0156] In this embodiment, vector median filtering is performed on the dip angles in the x direction and the dip angles in the y direction of the common angle data volume in the seismic data, and the filtered dip angles in the x direction and the y direction are used as the common angle data volume after the first denoising.

[0157] In this embodiment, vector median filtering is performed on the dip angle in the x direction of the common angle data volume in the seismic data, including:

[0158] The dip angle in the x direction of the common angle data volume in the seismic data is used as the original dip angle vector in the x direction;

[0159] A plurality of x-direction vector groups are formed with each inclination angle of the x-direction inclination original vector as the center;

[0160] Selecting an x-direction median vector in each x-direction vector group, wherein the sum of distances between the x-direction median vector and all other vectors in the x-direction vector group in which the x-direction median vector is located is the smallest;

[0161] The x-direction median vector of the multiple x-direction vector groups is the inclination angle in the x-direction after filtering;

[0162] The filtered inclination angle in the x direction is used as the common angle data volume after the first denoising.

[0163] In this embodiment, vector median filtering is performed on the dip angle in the y direction of the common angle data volume in the seismic data.

[0164] The dip angle in the y direction of the common angle data volume in the seismic data is used as the original dip angle vector in the y direction;

[0165] A plurality of y-direction vector groups are formed with each inclination angle of the y-direction inclination original vector as the center;

[0166] Selecting a median vector in the y direction from each y direction vector group, wherein the sum of distances between the median vector in the y direction and all other vectors in the y direction vector group in which the median vector in the y direction belongs is the smallest;

[0167] The y-direction median vector of the plurality of y-direction vector groups is the inclination angle in the y-direction after filtering;

[0168] The filtered inclination angle in the y direction is used as the common angle data volume after the first denoising.

[0169] (3) Perform vector median filtering on the common angle data volume along the inclination angle.

[0170] In this embodiment, the time parameter of the common angle data volume calculated according to the filtered inclination angle in the x direction and the inclination angle in the y direction is used as the filtering object.

[0171] In this embodiment, filtering the time parameters of the common angle data volume includes:

[0172] The time parameter of the common angle data volume is used as the original time vector;

[0173] A plurality of time vector groups are formed with each time of the original time vector as the center;

[0174] Selecting a time median vector in each time vector group, wherein the sum of distances between the time median vector and all other vectors in the time vector group to which it belongs is the smallest;

[0175] The time median vectors of the multiple time vector groups are the time parameters of the filtered common angle data volume.

[0176] In this embodiment, the time parameters of the common angle data volume calculated according to the filtered inclination angle in the x direction and the inclination angle in the y direction include:

[0177] The true inclination is calculated from the filtered inclination in the x-direction and the inclination in the y-direction based on the following expression:

[0178]

[0179] Among them, θ is the true inclination, θx is the inclination in the x direction after filtering, and θy is the inclination in the y direction.

[0180] The time parameters of the common angle data volume are calculated from the true inclination based on the following expression:

[0181]

[0182] Among them, t is the time parameter of the common angle data volume, h is the burial depth, x is the offset, θ is the true inclination, and v is the wave velocity.

[0183] The above-mentioned processor can be a general-purpose processor, including a central processing unit (CPU), a network processor (NP), etc.; it can also be a digital signal processor (DSP), an application specific integrated circuit (ASIC), a field programmable gate array (FPGA) or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components.

[0184] Alternatively, the storage medium may be a non-transitory computer-readable storage medium, for example, the non-transitory computer-readable storage medium may be a ROM, a random access memory (RAM), a CD-ROM, a magnetic tape, a floppy disk, an optical data storage device, and the like.

[0185] An embodiment of the present invention further provides a computer program product, including a computer program, which, when executed by a processor, implements the steps of the seismic data denoising method in any possible implementation manner described above.

[0186] In the above embodiments, it can be implemented in whole or in part by software, hardware, firmware or any combination thereof. When implemented using software, it can be implemented in whole or in part in the form of a computer program product. The computer program product includes one or more computer instructions. When the computer program instructions are loaded and executed on a computer, the process or function according to the embodiment of the present invention is generated in whole or in part. The computer can be a general-purpose computer, a special-purpose computer, a computer network, or other programmable devices. The computer instructions can be stored in a computer-readable storage medium, or transmitted from one computer-readable storage medium to another computer-readable storage medium. For example, the computer instructions can be transmitted from a website site, a computer, a server or a data center by wired (e.g., coaxial cable, optical fiber, digital subscriber line (DSL)) or wireless (e.g., infrared, wireless, microwave, etc.) mode to another website site, computer, server or data center. The computer-readable storage medium can be any available medium that a computer can access or a data storage device such as a server or a data center that includes one or more available media integration. The available medium can be a magnetic medium (e.g., a floppy disk, a hard disk, a tape), an optical medium (e.g., a DVD), or a semiconductor medium (e.g., a solid-state hard disk Solid State Disk (SSD)), etc.

[0187] Embodiment 5

[0188] In order to solve the above technical problems existing in the prior art, an embodiment of the present invention further provides a computer device.

[0189] In one embodiment, the computer device of this embodiment includes a memory and a processor. The memory stores a computer program. When the computer program is executed by the processor, the following seismic data denoising method is implemented:

[0190] S11, estimating the inclination of a common angle data volume in the seismic data, wherein the common angle data volume is a data volume with the same incident angle in the seismic data;

[0191] S12, performing vector median filtering on the inclination of the common angle data volume to perform first denoising on the common angle data volume;

[0192] S13, performing vector median filtering on the common angle data volume after the first denoising along the inclination angle, so as to perform secondary denoising on the common angle data volume.

[0193] In another embodiment, the computer device of this embodiment includes a memory and a processor, and a computer program is stored in the memory. When the computer program is executed by the processor, the following seismic data denoising method is implemented:

[0194] S21, estimating the dip angles in the x-direction and the y-direction of the common angle data volume in the seismic data by using any one of a local dip angle calculation method based on plane wave decomposition, a direct dip angle calculation method, a local dip angle calculation method based on Hilbert transform, and a local dip angle calculation method based on a time-distance curve relationship;

[0195] S22, respectively performing vector median filtering on the dip angle in the x direction and the dip angle in the y direction of the common angle data volume in the seismic data, and using the dip angle in the x direction and the dip angle in the y direction after filtering as the common angle data volume after the first denoising;

[0196] S231, calculating the time parameter of the common angle data volume according to the filtered inclination angle in the x direction and the inclination angle in the y direction;

[0197] S232, using the time parameter of the common angle data volume as the original time vector;

[0198] S233, forming a plurality of time vector groups with each time of the original time vector as the center;

[0199] S234, selecting a time median vector in each time vector group, wherein the sum of distances between the time median vector and all other vectors in the time vector group to which it belongs is the smallest;

[0200] S235, the time median vectors of the multiple time vector groups are the time parameters of the filtered common-angle data volume.

[0201] In this embodiment, in step S22, vector median filtering is performed on the dip angles in the x direction and the dip angles in the y direction of the common angle data volume in the seismic data, and the dip angles in the x direction and the dip angles in the y direction after filtering are used as the common angle data volume after the first denoising, including:

[0202] The dip angle in the x direction and the dip angle in the y direction of the common angle data volume in the seismic data are used as the original dip vector in the x direction and the original dip vector in the y direction respectively;

[0203] A plurality of x-direction vector groups are formed with each inclination angle of the x-direction inclination original vector as the center;

[0204] Selecting an x-direction median vector in each x-direction vector group, wherein the sum of distances between the x-direction median vector and all other vectors in the x-direction vector group in which the x-direction median vector is located is the smallest;

[0205] The x-direction median vector of the multiple x-direction vector groups is the inclination angle in the x-direction after filtering;

[0206] A plurality of y-direction vector groups are formed with each inclination angle of the y-direction inclination original vector as the center;

[0207] Selecting a median vector in the y direction from each y direction vector group, wherein the sum of distances between the median vector in the y direction and all other vectors in the y direction vector group in which the median vector in the y direction belongs is the smallest;

[0208] The y-direction median vector of the plurality of y-direction vector groups is the inclination angle in the y-direction after filtering;

[0209] The filtered inclination angle in the x direction and the filtered inclination angle in the y direction are used as the common angle data volume after the first denoising.

[0210] In this embodiment, in step S231, calculating the time parameter of the common angle data volume according to the filtered inclination angle in the x direction and the inclination angle in the y direction includes:

[0211] The true inclination is calculated from the filtered inclination in the x-direction and the inclination in the y-direction based on the following expression:

[0212]

[0213] Among them, θ is the true inclination, θx is the inclination in the x direction after filtering, and θy is the inclination in the y direction.

[0214] The time parameters of the common angle data volume are calculated from the true inclination based on the following expression:

[0215]

[0216] Among them, t is the time parameter of the common angle data volume, h is the burial depth, x is the offset, θ is the true inclination, and v is the wave velocity.

[0217] In another embodiment, the computer device of this embodiment includes a memory and a processor, and a computer program is stored in the memory. When the computer program is executed by the processor, the following seismic data denoising method is implemented:

[0218] (1) Estimate the inclination angles in the x and y directions of the common angle data volume;

[0219] In this embodiment, the common angle data volume is a data volume with the same incident angle extracted from the pre-stack CRP gathers collected in the shale oil target exploration area of ​​Qianjiang Sag, such as Figure 3 shown.

[0220] In this embodiment, the methods for estimating the inclination angles in the x and y directions of the common angle data body include a direct calculation method, a local inclination angle calculation method based on Hilbert transform, a local inclination angle calculation method based on plane wave decomposition, a local inclination angle calculation method based on the time-distance curve relationship, and a local inclination angle calculation method based on plane wave decomposition, among which the local inclination angle calculation method based on plane wave decomposition is preferred.

[0221] (2) Perform vector median filtering on the estimated inclination angle;

[0222] In this embodiment, vector median filtering is performed on the dip angles in the x direction and the dip angles in the y direction of the common angle data volume in the seismic data, and the filtered dip angles in the x direction and the y direction are used as the common angle data volume after the first denoising.

[0223] In this embodiment, vector median filtering is performed on the dip angle in the x direction of the common angle data volume in the seismic data, including:

[0224] The dip angle in the x direction of the common angle data volume in the seismic data is used as the original dip angle vector in the x direction;

[0225] A plurality of x-direction vector groups are formed with each inclination angle of the x-direction inclination original vector as the center;

[0226] Selecting an x-direction median vector in each x-direction vector group, wherein the sum of distances between the x-direction median vector and all other vectors in the x-direction vector group in which the x-direction median vector is located is the smallest;

[0227] The x-direction median vector of the multiple x-direction vector groups is the inclination angle in the x-direction after filtering;

[0228] The filtered inclination angle in the x direction is used as the common angle data volume after the first denoising.

[0229] In this embodiment, vector median filtering is performed on the dip angle in the y direction of the common angle data volume in the seismic data.

[0230] The dip angle in the y direction of the common angle data volume in the seismic data is used as the original dip angle vector in the y direction;

[0231] A plurality of y-direction vector groups are formed with each inclination angle of the y-direction inclination original vector as the center;

[0232] Selecting a median vector in the y direction from each y direction vector group, wherein the sum of distances between the median vector in the y direction and all other vectors in the y direction vector group in which the median vector in the y direction belongs is the smallest;

[0233] The y-direction median vector of the plurality of y-direction vector groups is the inclination angle in the y-direction after filtering;

[0234] The filtered inclination angle in the y direction is used as the common angle data volume after the first denoising.

[0235] (3) Perform vector median filtering on the common angle data volume along the inclination angle.

[0236] In this embodiment, the time parameter of the common angle data volume calculated according to the filtered inclination angle in the x direction and the inclination angle in the y direction is used as the filtering object.

[0237] In this embodiment, filtering the time parameters of the common angle data volume includes:

[0238] The time parameter of the common angle data volume is used as the original time vector;

[0239] A plurality of time vector groups are formed with each time of the original time vector as the center;

[0240] Selecting a time median vector in each time vector group, wherein the sum of distances between the time median vector and all other vectors in the time vector group to which it belongs is the smallest;

[0241] The time median vectors of the multiple time vector groups are the time parameters of the filtered common angle data volume.

[0242] In this embodiment, the time parameters of the common angle data volume calculated according to the filtered inclination angle in the x direction and the inclination angle in the y direction include:

[0243] The true inclination is calculated from the filtered inclination in the x-direction and the inclination in the y-direction based on the following expression:

[0244]

[0245] Among them, θ is the true inclination, θx is the inclination in the x direction after filtering, and θy is the inclination in the y direction.

[0246] The time parameters of the common angle data volume are calculated from the true inclination based on the following expression:

[0247]

[0248] Among them, t is the time parameter of the common angle data volume, h is the burial depth, x is the offset, θ is the true inclination, and v is the wave velocity.

[0249] The memory may include a random access memory (RAM) or a non-volatile memory, such as at least one disk memory. Optionally, the memory may also be at least one storage device located away from the processor.

[0250] The above-mentioned processor can be a general-purpose processor, including a central processing unit (CPU), a network processor (NP), etc.; it can also be a digital signal processor (DSP), an application specific integrated circuit (ASIC), a field programmable gate array (FPGA) or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components.

[0251] Although the embodiments disclosed in the present invention are as above, the contents described are only embodiments adopted for facilitating the understanding of the present invention and are not intended to limit the present invention. Any technician in the technical field to which the present invention belongs can make any modifications and changes in the form and details of the implementation without departing from the spirit and scope disclosed in the present invention, but the protection scope of the present invention shall still be subject to the scope defined in the attached claims.

Claims

1. A method for denoising seismic data, characterized in that: The following steps are involved: Estimate the dip angle of the co-angle data volume in seismic data; Performing vector median filtering on the inclination of the common angle data volume to perform first denoising on the common angle data volume; Performing vector median filtering on the common angle data volume after the first denoising along the inclination angle to perform secondary denoising on the common angle data volume; The step of performing vector median filtering on the inclination angle of the common angle data volume comprises: Perform vector median filtering on the dip angles in the x direction and the dip angles in the y direction of the common angle data volume in the seismic data, respectively, and use the dip angles in the x direction and the dip angles in the y direction after filtering as the common angle data volume after the first denoising; The method of performing vector median filtering on the common angle data volume after the first denoising along the inclination angle to perform secondary denoising on the common angle data volume comprises: Calculate the time parameter of the common angle data volume according to the filtered inclination angle in the x direction and the inclination angle in the y direction; The time parameter of the common angle data volume is used as the original time vector; A plurality of time vector groups are formed with each time of the original time vector as the center; Selecting a time median vector in each time vector group, wherein the sum of distances between the time median vector and all other vectors in the time vector group to which it belongs is the smallest; The time median vector of the multiple time vector groups is the time parameter of the filtered common angle data volume; The step of calculating the time parameter of the common angle data volume according to the filtered inclination angle in the x direction and the inclination angle in the y direction comprises: Calculate the true inclination angle according to the filtered inclination angle in the x direction and the inclination angle in the y direction; The time parameters of the common angle data volume are calculated based on the true inclination.

2. The method according to claim 1, characterized in that The common angle data volume is a data volume with the same incident angle in the seismic data.

3. The method according to claim 2, characterized in that The estimating the inclination of the common angle data volume in the seismic data comprises: The dip angles in the x-direction and y-direction of the common angle data volume in the seismic data are estimated by using any one of the local dip angle calculation methods based on plane wave decomposition, the direct dip angle calculation method, the local dip angle calculation method based on Hilbert transform and the local dip angle calculation method based on time-distance curve relationship.

4. The method according to claim 1, characterized in that: The method of performing vector median filtering on the dip angles in the x direction and the dip angles in the y direction of the common angle data volume in the seismic data, and using the dip angles in the x direction and the dip angles in the y direction after filtering as the common angle data volume after the first denoising, comprises: The dip angle in the x direction and the dip angle in the y direction of the common angle data volume in the seismic data are used as the original dip vector in the x direction and the original dip vector in the y direction respectively; A plurality of x-direction vector groups are formed with each inclination angle of the x-direction inclination original vector as the center; Selecting an x-direction median vector in each x-direction vector group, wherein the sum of distances between the x-direction median vector and all other vectors in the x-direction vector group in which the x-direction median vector is located is the smallest; The x-direction median vector of the multiple x-direction vector groups is the inclination angle in the x-direction after filtering; A plurality of y-direction vector groups are formed with each inclination angle of the y-direction inclination original vector as the center; Selecting a median vector in the y direction from each y direction vector group, wherein the sum of distances between the median vector in the y direction and all other vectors in the y direction vector group in which the median vector in the y direction belongs is the smallest; The y-direction median vector of the plurality of y-direction vector groups is the inclination angle in the y-direction after filtering; The filtered inclination angle in the x direction and the filtered inclination angle in the y direction are used as the common angle data volume after the first denoising.

5. The method according to claim 1, characterized in that The seismic data are pre-stack common reflection point gather data.

6. A storage medium having a computer program stored thereon, characterized in that: When the computer program is executed by a processor, the steps of the method according to any one of claims 1 to 5 are implemented.

7. A computer device comprising a memory and a processor, characterized in that: The memory stores a computer program, which implements the steps of the method according to any one of claims 1 to 5 when executed by the processor.

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