A method and device for shielding against strong seismic reflections

Abstract

The present invention discloses a method and device for removing strong seismic reflections and shielding. The method comprises: calculating weighted average seismic trace data based on the seismic trace data of a current seismic trace and adjacent seismic traces in seismic data; extracting seismic atomic parameters corresponding to the location of the strongest amplitude based on the weighted average seismic trace data; and subtracting the seismic atoms corresponding to the seismic atomic parameters from the weighted average seismic trace data to obtain seismic trace data for the current seismic trace after removing strong reflections. The present invention removes strong seismic reflections and avoids shielding weak useful signals, thereby significantly improving the accuracy of identifying strong reflection isotropic axes. This method has important guiding significance for the exploration and development of oil and gas reservoirs hidden below strong seismic reflection axes.

Description

Technical Field

[0001] The present invention relates to the field of oil and gas field seismic exploration, and in particular to a method and device for removing strong seismic reflection shielding. Background Art

[0002] With the continuous advancement of oil and gas exploration, the identification and interpretation of thin reservoirs and lithologic traps have become a research focus in the fine interpretation of seismic data. When the reservoir is overlain by special strata such as large coal seams or thick source rocks, the strong impedance difference between the reservoir and the adjacent strata will show strong amplitude characteristics on the seismic profile, which obscures the information of the underlying reservoir and makes it difficult to effectively predict the underlying reservoir.

[0003] Furthermore, in shale-developed areas, the large impedance difference between the upper and lower interfaces can lead to the appearance of strong reflection events, severely shielding adjacent reservoir signals and reducing reservoir prediction accuracy. Conventional seismic data struggles to meet the demands of detailed interpretation of complex reservoirs, especially when the target stratum is near a coal seam. Effective reservoir information can be drowned out by the strong reflections from the coal seam, making effective reservoir prediction difficult.

[0004] Therefore, eliminating the shielding of weak reservoir reflection signals by strong seismic reflections caused by strong interference layers is of great significance for improving reservoir prediction accuracy and determining favorable reservoir space. Summary of the Invention

[0005] In view of the technical defects and technical drawbacks in the prior art, the embodiments of the present invention provide a method and device for removing strong seismic reflection shielding that overcomes or at least partially solves the above problems to meet the needs of detailed analysis of seismic data.

[0006] To achieve the above-mentioned object, an embodiment of the present invention provides a method for removing strong seismic reflection shielding, which includes:

[0007] Calculating weighted average seismic trace data based on seismic trace data of a current seismic trace and seismic trace data of adjacent seismic traces adjacent to the current seismic trace in the seismic data;

[0008] Extracting the seismic atomic parameters corresponding to the position of the strongest amplitude according to the weighted average seismic trace data;

[0009] The seismic atoms corresponding to the seismic atom parameters are subtracted from the weighted average seismic trace data to obtain the seismic trace data of the current seismic trace after strong reflections are removed.

[0010] Another embodiment of the present invention further provides a strong seismic reflection shielding device, comprising:

[0011] Data acquisition module, used to acquire seismic data;

[0012] A first operation module is used to calculate weighted average seismic trace data based on seismic trace data of a current seismic trace and seismic trace data of adjacent seismic traces adjacent to the current seismic trace in the seismic data;

[0013] a parameter extraction module, configured to extract the seismic atomic parameters corresponding to the position of the strongest amplitude based on the weighted average seismic trace data; and

[0014] The second operation module is used to subtract the seismic atoms corresponding to the seismic atom parameters from the weighted average seismic trace data to obtain the seismic trace data of the current seismic trace after removing strong reflections.

[0015] The embodiments of the present invention achieve at least the following technical effects: it removes strong seismic reflections and avoids shielding of weak useful signals, thereby greatly improving the recognition accuracy of strong reflection co-directional axes, which has important guiding significance for the exploration and development of oil and gas reservoirs hidden below the strong seismic reflection axes.

[0016] Other features and advantages of the present invention will be described in the following description, and in part will become apparent from the description, or will be understood by practicing the present invention. The purpose and other advantages of the present invention can be realized and obtained by the structure described in the written description, claims, and drawings.

[0017] The technical solution of the present invention is further described in detail below through the accompanying drawings and embodiments. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] 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:

[0019] Figure 1 A flow chart of a method for removing strong seismic reflection shielding provided by an embodiment of the present invention;

[0020] Figure 2 for Figure 1 Specific flow chart of step 300;

[0021] Figure 3 This is a diagram showing the shape of seismic wavelets in Hilbert space;

[0022] Figures 4 to 11 It is a comparison diagram of experimental data for illustrating the effect of the present invention;

[0023] Figure 12 A schematic structural diagram of a seismic strong reflection shielding device provided in an embodiment of the present invention. DETAILED DESCRIPTION

[0024] Exemplary embodiments of the present disclosure will be described in more detail below with reference to the accompanying drawings. Although exemplary embodiments of the present disclosure are shown in the accompanying drawings, it should be understood that the present disclosure can be implemented in various forms and should not be limited by the embodiments set forth herein. Rather, these embodiments are provided to enable a more thorough understanding of the present disclosure and to fully convey the scope of the present disclosure to those skilled in the art.

[0025] Exemplary embodiments will be described in detail herein, examples of which are illustrated in the accompanying drawings. In the following description, when referring to the drawings, like numbers in different figures represent like or similar elements unless otherwise indicated. The embodiments described in the following exemplary embodiments are not intended to represent all possible embodiments consistent with the present invention. Rather, they are merely examples of apparatus and methods consistent with certain aspects of the present invention, as detailed in the appended claims.

[0026] First, the technical terms involved in each embodiment of the present invention are briefly described as follows:

[0027] Lithologic traps are formed by changes in the lithology or physical properties of a reservoir. Traps prevent further migration of oil and gas, allowing them to accumulate within them. Traps are effective spaces capable of capturing dispersed hydrocarbons, forming oil and gas accumulations. They possess the ability to store oil and gas, but not all oil and gas are contained within a trap. Once sufficient oil and gas enter a trap, filling it or occupying a portion of it, an oil and gas reservoir is formed.

[0028] Source rock: a type of rock that can produce or has produced mobile hydrocarbons, including oil source rock, gas source rock and oil and gas source rock. It is usually called oil source rock. It is a rock rich in organic matter and produces and discharges large amounts of oil and gas.

[0029] A seismic profile, also called a seismic record profile, is a map of seismic data that shows a specific survey line. Seismic record profiles can be divided into two types: time profiles and depth profiles, depending on the physical dimensions used for the vertical axis.

[0030] Rock wave impedance, also known as wave impedance, refers to the stress required to induce a disturbance in the rock and cause a particle to produce a unit vibration velocity. The greater the wave impedance, the greater the stress required to produce a unit vibration velocity; conversely, the smaller the wave impedance, the smaller the stress required to produce a unit vibration velocity.

[0031] Events are lines connecting extreme values ​​(commonly known as peaks or troughs) of identical vibration phase on each trace in a seismic record. When interpreting seismic exploration data, different events are often drawn based on the regular occurrence of similar vibrations on the seismic record. These events represent seismic waves at different levels.

[0032] Seismic reflection wave method: A method of artificial seismic exploration using seismic reflection waves. It is the primary means of continental shelf oil and gas exploration. The measurement results can accurately determine the depth and shape of interfaces, delineate local structures, and determine stratum lithology. By applying the dynamic characteristics of waves to seismic stratigraphic studies, it is possible to analyze seismic facies, infer sedimentary environments, and further clarify the source-reservoir-caprock combination conditions of oil and gas reservoirs.

[0033] Matching Pursuit (MP) algorithm: It was originally an analysis tool for time-frequency analysis. Its purpose is to decompose a known signal into a weighted sum of many signals called atomic signals, and attempt to find the solution that is closest to the original signal. The atomic signal is an element in a very large atomic library. The algorithm decomposes the original signal into a linear combination of multiple time-frequency atoms (also called seismic atoms in this invention), which can also be called matching wavelets. The selection of matching wavelets is determined by the wavelet control parameters. Once a set of wavelet control parameters is determined, a unique wavelet is obtained. The matching pursuit algorithm has achieved good application results in time-frequency analysis, spectrum imaging, thin sand body prediction, filtering denoising, residual time difference correction, etc.

[0034] This embodiment provides a method for shielding against strong earthquake reflections. Figure 1 As shown, the following steps may be included:

[0035] Step 100: Acquire seismic data.

[0036] The seismic data may be, for example, exploration data such as seismic profiles, seismic tectonic maps, active fault distribution maps, and related investigation reports and instructions obtained from earthquake historical records or through methods such as seismic reflection wave methods.

[0037] Specifically, the seismic data may be pre-post-stacked seismic data. Post-stack processing includes, but is not limited to, static correction, denoising, amplitude compensation, velocity analysis, dynamic correction, and migration. The final processed post-stack seismic data is equivalent to data acquired under self-excitation and self-collection conditions and can be expressed as s(t,x), where t represents the two-way travel time of the seismic wave and x represents the seismic trace number.

[0038] During post-stack denoising, it's important to consider filtering out both low-frequency and high-frequency information. This is because high-frequency components are crucial for vertical reservoir resolution, while low-frequency components significantly impact lateral variations in geological structures. In practical research, FK filtering in the frequency-wavenumber domain can be used, rather than the commonly used bandpass filtering, to fully preserve the shared information between high and low frequencies.

[0039] Step 200 : Calculate weighted average seismic trace data based on the seismic trace data of the current seismic trace and the seismic trace data of adjacent seismic traces adjacent to the current seismic trace in the seismic data.

[0040] Seismic traces consist of energy within a specific frequency range. Seismic waves are recorded at each observation point and pass through three basic links: the detector, the amplification system, and the recording system. These are collectively referred to as "seismic traces." Fourier transforms can decompose signals into distinct sinusoidal waves, whose amplitude and phase vary with frequency. Seismic wavelets are composed of an infinite number of sinusoidal waves with appropriate relative amplitudes and phases. Seismic trace data (profiles) consist of a series of seismic waveform traces, each a one-dimensional signal channel. The analysis and processing of seismic traces has important theoretical and practical value for studying stratigraphic geological structures and determining reservoir locations.

[0041] The "current seismic trace" refers to the seismic trace from which the strong seismic reflection shielding is to be removed; the "adjacent seismic trace" refers to the seismic trace next to the current seismic trace, including both the directly adjacent seismic trace next to the current seismic trace and the indirectly adjacent seismic trace adjacent to the directly adjacent seismic trace.

[0042] The weight of the weighted average can be selected based on factors such as the relative position of the adjacent seismic traces to the current seismic trace. For example, a lower weight can be assigned to adjacent seismic traces that are farther from the current seismic trace, while a higher weight can be assigned to adjacent seismic traces that are closer to the current seismic trace.

[0043] The “seismic trace data” may be, for example, the energy of a seismic trace.

[0044] Traditional seismic strong reflection removal and shielding techniques calculate the atomic parameters corresponding to each strong reflection event in each seismic channel based on single-channel seismic data. Due to the influence of seismic noise and algorithm stability, the calculated strong reflection atomic parameters often exhibit lateral discontinuities, affecting the strong reflection removal and shielding effectiveness. To address this, this step incorporates information from neighboring seismic channels during the strong reflection matching process for the current seismic channel, thereby enhancing the lateral stability and accuracy of the picked strong seismic reflections.

[0045] Step 300: extracting the seismic atomic parameters corresponding to the position of the strongest amplitude based on the weighted average seismic trace data.

[0046] The "maximum amplitude position" refers to the location where the seismic reflection wave has the highest energy. The "seismic atom parameters" refer to the coefficients of each seismic atom when the matching pursuit algorithm is used to decompose seismic trace data into linear combinations of multiple seismic atoms. Seismic atoms are selected from an atom library, such as the Morlet atom library and the Ricker atom library.

[0047] The specific extraction process will be further explained in the subsequent content.

[0048] Step 400: Subtract the seismic atoms corresponding to the seismic atom parameters from the weighted average seismic trace data.

[0049] The "seismic atom corresponding to the seismic atom parameter" is the seismic atom corresponding to the location of the strongest amplitude, essentially the seismic atom corresponding to the location of the strongest envelope energy on the current seismic trace. This seismic atom represents a strong seismic reflection that can shield useful weak signals. By subtracting this seismic atom from the weighted average seismic trace data, the seismic trace data after strong reflection removal is obtained.

[0050] Step 500: Repeat the above process using each seismic trace in the seismic data as the current seismic trace to obtain seismic data after strong reflections are removed.

[0051] In this step, each seismic trace in the seismic data is shielded from strong seismic reflections. Afterwards, data interpretation and analysis can be performed on the seismic data after strong reflections have been removed.

[0052] The de-reflected data channels corresponding to each seismic data point are combined in a specific arrangement to form a de-reflected data volume or profile. If the acquired data still exhibits lateral continuity impairment at the de-reflected locations, two-dimensional or three-dimensional smoothing filtering can be used to improve the data's lateral continuity. Furthermore, seismic interpretation can be performed using various methods, such as cross-section or slice analysis, on the de-reflected seismic data to improve the accuracy of reservoir identification under strong reflection shielding.

[0053] It should be noted here that if the seismic trace data after removing strong reflections for the current seismic trace obtained in the aforementioned step 400 can meet the needs, step 500 may not be performed.

[0054] The method described in this embodiment achieves the removal of strong seismic reflections and avoids the shielding of weak useful signals, thereby greatly improving the recognition accuracy of strong reflection isotropic axes, which has important guiding significance for the exploration and development of oil and gas reservoirs hidden below the strong seismic reflection axes.

[0055] Moreover, the present embodiment takes into account the seismic trace data of the current seismic trace and the adjacent seismic traces when extracting strong seismic reflections, thereby introducing a multi-channel matching pursuit algorithm to replace the traditional single-channel matching pursuit algorithm. Compared with the method based on single-channel calculation and channel-by-channel scanning, the problem of poor lateral continuity of strong reflection event axes in the traditional method in removing strong seismic reflection shielding is optimized, and the lateral continuity characteristics of the strong reflection atoms identified between adjacent channels are ensured, thereby improving the lateral continuity of the seismic strong reflection identification results and the accuracy of the fine interpretation of seismic data.

[0056] The following reference Figure 2, a specific optional implementation of the above step 300 is described in detail, as shown in the figure, including the following steps:

[0057] Step 310: Determine the vector length of the seismic atom in the atom library according to the position of the strongest amplitude.

[0058] While obtaining the instantaneous phase and instantaneous frequency at the location of strong seismic reflection, selecting an appropriate vector length of seismic atoms helps to improve the accuracy and efficiency of atom identification.

[0059] Typically, the effective duration of a seismic atom is approximately 150ms. However, in actual seismic data, due to the thin-layer interference effect of seismic waves, the sidelobe information of seismic atoms is distorted by interference from seismic reflections in adjacent layers. For example, the matching pursuit method identifies the optimal seismic atom based on the inner product of the entire trace data and the seismic atom, ignoring the influence of the thin-layer interference effect and reducing the accuracy of the atom parameter determination. Furthermore, because seismic atoms only have energy locally and their energy values ​​are zero elsewhere, performing the inner product based on the entire trace data results in a large number of meaningless operations, greatly reducing the algorithm's efficiency.

[0060] like Figure 3 The figure shows the morphology of seismic wavelets in Hilbert space. Hilbert space is a complete inner product space and a generalization of Euclidean space. It is no longer limited to finite dimensions. As shown by the arrow in the figure, the modulus (or energy) of the seismic wavelet is basically zero outside the arrow. However, in traditional algorithms, the matching of wavelets corresponding to strong reflection events is performed by performing full-length inner products on seismic traces and seismic wavelets of equal length. Since the modulus (energy) of seismic wavelets is zero outside a certain range, the inner product operation outside this range of traditional methods is meaningless, consuming a lot of machine time and reducing computational efficiency. In addition, due to the interference effect between seismic reflection waves from different strata, limiting the length of the seismic atom inner product operation to a certain range can also reduce the interference effect of adjacent layers and improve the accuracy of seismic atom matching.

[0061] To this end, a reasonable vector length can be set during the seismic atom matching process, for example, a vector length of 100ms can be determined with the strongest amplitude position as the center. By selecting an appropriate range to perform the inner product operation of the seismic trace and the atom, the influence of the interference effect of the adjacent layer on the de-strong reflection shielding result can be reduced, thereby improving the accuracy of seismic strong reflection identification. In addition, controlling a reasonable seismic atom inner product length can also avoid meaningless inner product operations on the non-information part of the atom (zero value), greatly reducing the amount of computation required for de-strong reflection shielding and improving computational efficiency.

[0062] Step 320 : Using the vector length as the inner product length, perform an inner product operation on the weighted average seismic trace data and a plurality of seismic atoms selected from the atom library.

[0063] The inner product of vectors, also known as the dot product or scalar product, is a binary operation that accepts two vectors on the real number R and returns a real-valued scalar. It is the standard inner product in Euclidean space. Its geometric meaning represents the angle between two vectors, or the projection of one vector in the direction of another. The best matching atom in MP is chosen by selecting the one with the largest inner product, that is, the one with the longest vertical projection of the signal (or residual) onto the atom (unit).

[0064] In step 330, the parameter at which the result of the inner product operation reaches a maximum value is used as the seismic atomic parameter.

[0065] Thereafter, in the above-mentioned step 400, the seismic atom corresponding to the parameter when the result of the inner product operation is maximized is used as the target seismic atom; the inner product operation is performed on the weighted average seismic trace data and the target seismic atom to obtain the amplitude of the target seismic atom; the amplitude of the target seismic atom is multiplied by the seismic atom parameter to obtain the energy of the target seismic atom; and the energy of the target seismic atom is subtracted from the weighted average seismic trace data.

[0066] Specifically, the above process can be expressed mathematically as follows:

[0067] For any seismic data, it can be recorded as s0(t), and its adjacent seismic data are recorded as [s1(t), s2(t), ..., s N-1 (t)]. Since s0(t) and [s1(t),s2(t),...,s N-1 The data recorded for the current channel (t) is relatively close, so there must be a strong correlation between it and the seismic waveforms of each channel. To this end, the current channel data can be fused with the adjacent channel information through a weighted average method to improve the lateral stability of strong seismic reflection identification. Let the weighted average data be s(t), which can be calculated using the following formula:

[0068]

[0069] Among them, a i is the weighting coefficient (i=0, 1, ..., N-1). By adjusting a, the contribution weight of any adjacent channel to the current channel can be controlled. The value of the weight coefficient is generally related to the distance between the adjacent channel and the adjacent channel. The smaller the distance, the larger the weight coefficient, and vice versa.

[0070] Obtaining weighted average data After that, strong reflection identification can be carried out on the above seismic traces. In the seismic strong reflection identification algorithm based on matching pursuit, the usual method is to first obtain the instantaneous parameter properties of the corresponding atoms, including instantaneous phase, instantaneous frequency, etc.

[0071] Set up earthquake tunnel The corresponding complex channel Hs(t) is:

[0072]

[0073] Where: R(t) is the imaginary part of the complex trace, i.e. the seismic trace The Hilbert transform result of ; j represents the imaginary unit. Complex trace data refers to the seismic trace data obtained after the Hilbert transform. The data before the transform can also be called real seismic trace data.

[0074] On this basis, the instantaneous phase of an earthquake can be expressed as:

[0075]

[0076] For the instantaneous frequency InsFreq(t), it can be expressed as:

[0077]

[0078] where InsPhase'(t) is the first derivative of the instantaneous phase and can be calculated using the following formula:

[0079]

[0080] Therefore, the instantaneous frequency InsFreq(t) can be written as:

[0081]

[0082] On the basis of selecting the appropriate inner product length, the time position of the seismic atom is calculated to determine the seismic atom corresponding to the strong reflection position. The best unit for calculation is the seismic atom g r Can meet:

[0083]

[0084] Where: <.,.> represents the inner product operation; the denominator is the normalized operation coefficient; argmax is a function that finds the parameters (set) of a function and returns the parameters when the function reaches its maximum value. For example, when y = max f(t), y is the maximum value of the f(t) function; when y = argmax f(t), y is the parameter t when the f(t) function reaches its maximum value.

[0085] On this basis, the amplitude (ie energy) corresponding to the current best atom can be expressed as:

[0086]

[0087] Therefore, the seismic trace s'(t) after de-reflection shielding can be written as:

[0088]

[0089] The following experimental data reflects the problems existing in the prior art and the technical effects achieved by the present invention.

[0090] Problems in the existing technology:

[0091] (1) The traditional matching pursuit method ignores the correlation between adjacent channels of seismic data. The seismic strong reflection event axis calculated by it is usually highly unstable in the lateral direction, which affects the accuracy of seismic strong reflection shielding. In this regard, by introducing the multi-channel matching pursuit method, the seismic neighborhood information is taken into account in the process of extracting seismic strong reflection information, thereby improving the lateral stability and accuracy of seismic strong reflection shielding.

[0092] (2) The traditional method extends the seismic atom to the actual earthquake length and then performs inner product calculations to evaluate the degree of match between a certain atom and the strong seismic reflection event. This ignores the fact that the energy of seismic atoms is zero outside a certain range, and a large number of unnecessary calculations are performed, which reduces the operating efficiency.

[0093] (3) The traditional method does not consider the influence of the adjacent layer interference effect on the seismic strong reflection phase axis. The atomic parameters corresponding to the extracted strong reflection phase axis are greatly affected by the adjacent layer reflection, and the accuracy needs to be improved.

[0094] The above improvements of the present invention have achieved the following advantages:

[0095] 1. This technical solution adopts multi-channel matching pursuit technology to optimize the problem of poor lateral continuity of strong reflection phase axis in traditional methods for seismic strong reflection shielding, thereby improving the accuracy of the results;

[0096] 2. This technical solution controls the inner product length of seismic atoms in the identification of strong seismic reflection events to improve the accuracy of the results. Compared with traditional methods, the algorithm of the present invention reduces the influence of adjacent layer interference on the identification of strong seismic reflection events, and the extracted atoms are more accurate;

[0097] 3. This technical solution controls the inner product length of seismic atoms in identifying strong seismic reflection events. Compared with traditional methods, the algorithm of the present invention avoids redundant calculations at the position where the atomic modulus value is zero, greatly reducing the amount of calculation and improving the operation efficiency.

[0098] 4. The algorithm of this technical solution is simple and easy to implement, with high operating efficiency, no need for human-computer interaction, and easy to form software functional modules for promotion and application.

[0099] The comparison results based on experimental data are as follows:

[0100] Figure 4is a two-dimensional seismic numerical model containing strong reflection events inputted in an embodiment of the present invention; Figure 5 This embodiment is based on Figure 4 Results of strong reflection event identification using a 2D seismic numerical model as input: (a) represents the strong reflection event identified by the multi-channel matching pursuit algorithm; (b) represents the strong reflection event identified by the traditional single-channel matching pursuit algorithm.

[0101] As shown by the black arrows in the figure, compared with traditional identification methods, the strong reflection events identified by the multi-channel matching pursuit algorithm have better lateral stability and accuracy. The positions indicated by the arrows in the figure appear smoother, which can, to a certain extent, reduce the problem of poor lateral continuity of the strong reflection events caused by traditional channel-by-channel calculations.

[0102] Figure 6 This embodiment is based on Figure 4 De-reflection profiles obtained using a two-dimensional seismic numerical model as input: (a) represents the de-reflection seismic profile obtained using the multi-channel matching pursuit algorithm; (b) represents the de-reflection seismic profile obtained using the traditional single-channel matching pursuit algorithm.

[0103] As shown by the black arrows in the figure, compared with the traditional method, the seismic profile after removing the strong reflection shielding based on the multi-channel matching pursuit algorithm has a better ability to retain the diffraction waves near the bottom of the strong reflection axis, while in the results of the traditional method, the diffraction wave reflection characteristics are severely destroyed.

[0104] Figure 7 The two-dimensional wedge-shaped seismic reflection model with strong reflection event input in the embodiment of the present invention (a) and its corresponding maximum absolute amplitude value change law with seismic trace (b). Figure 7 As shown in (b), at the position of a quarter wavelength of the tuning thickness, the maximum absolute amplitude of the seismic reflection of the above model is the smallest.

[0105] Figure 8 This embodiment is based on Figure 7 Results of removing strong reflections obtained using a two-dimensional wedge-shaped seismic model as input: (a) represents the underlying seismic reflection characteristics without strong reflection events; (b) represents the underlying seismic reflection characteristics after removing strong reflections and shielding calculated with a controlled inner product length; (c) represents the underlying seismic reflection characteristics after removing strong reflections and shielding calculated with the original inner product length.

[0106] As shown by the black arrow in the figure, compared with the traditional method, the overall result of removing strong reflection shielding under the control of inner product length is more accurate, and its result is closer to Figure 8 For the model data in (a), the waveform residual is small.

[0107] Figure 9 A post-stack two-dimensional seismic profile containing strong reflections in a certain work area in western China inputted as an embodiment of the present invention; Figure 10 This embodiment is based on Figure 9 The post-stack 2D seismic profile is the strong reflection event identified as input: (a) represents the strong reflection event identified by the traditional method, and (b) represents the strong reflection event identified by the algorithm of the present invention.

[0108] As shown by the ellipse and arrow in the figure, compared with the traditional algorithm, the strong reflection event identified by the algorithm of the present invention has better lateral stability and no lateral discontinuity; among the strong reflection events identified by the traditional algorithm, the lateral stability of the seismic strong reflection event identified is relatively poor because the correlation between adjacent seismic channels and the atomic inner product length are not taken into account.

[0109] Figure 11 This embodiment is based on Figure 9 The post-stack 2D seismic profile is the input de-emphasized reflection profile: (a) represents the de-emphasized reflection profile obtained by the traditional method, and (b) represents the de-emphasized reflection profile obtained by the algorithm of the present invention.

[0110] As shown by the ellipse and arrow in the figure, compared with the traditional algorithm, the lateral stability of the phase axis in the de-emphasized reflection profile using the algorithm of the present invention is better, there is no lateral discontinuity, and the lateral change of the seismic reflection characteristics is more natural and continuous; in the de-emphasized reflection profile based on the traditional algorithm, since the correlation between seismic adjacent channels and the atomic inner product length are not taken into account, the lateral stability of the seismic reflection characteristics at the position of the de-emphasized reflection phase axis is relatively poor, and there are many abnormal seismic waveform processing phenomena, as shown by the arrows in the figure.

[0111] This embodiment provides a strong seismic reflection shielding device that can implement the above method, such as Figure 12 As shown, it includes: data acquisition simulation 10, a first operation module 20, a parameter extraction module 30, and a second operation module 40, and its working principle is as follows:

[0112] The data acquisition module 10 acquires seismic data, which may be seismic data that has been pre-post-stack processed.

[0113] Then, the first operation module 20 calculates the weighted average seismic trace data based on the seismic trace data of the current seismic trace and the adjacent seismic traces adjacent to the current seismic trace in the seismic data. The parameter extraction module 30 extracts the seismic atom parameters corresponding to the strongest amplitude position based on the weighted average seismic trace data. Specifically, the vector length of the seismic atoms in the atom library can be determined based on the strongest amplitude position; with the vector length as the inner product length, the inner product operation is performed on the weighted average seismic trace data and multiple seismic atoms selected from the atom library; and the parameter at the maximum value of the result of the inner product operation is used as the seismic atom parameter. The vector length can be 100ms centered on the strongest amplitude position.

[0114] Then, the second operation module 40 subtracts the seismic atom corresponding to the seismic atom parameter from the weighted average seismic trace data to obtain the seismic trace data of the current seismic trace after strong reflection removal. Specifically, the seismic atom corresponding to the parameter that maximizes the result of the inner product operation is used as the target seismic atom; an inner product operation is performed on the weighted average seismic trace data and the target seismic atom to obtain the amplitude of the target seismic atom; the amplitude of the target seismic atom is multiplied by the seismic atom parameter to obtain the energy of the target seismic atom; and the energy of the target seismic atom is subtracted from the weighted average seismic trace data.

[0115] Thereafter, optionally, the above process may be repeated using each seismic trace in the seismic data as the current seismic trace to obtain seismic data after strong reflections are removed.

[0116] The specific implementation process and corresponding technical effects of this embodiment can be found in the relevant content of the above method embodiment, which will not be repeated here.

[0117] Those skilled in the art will appreciate that embodiments of the present invention may be provided as methods, systems, or computer program products. Thus, the present invention may take the form of an entirely hardware embodiment, an entirely software embodiment, or an embodiment combining software and hardware. Furthermore, the present invention may take the form of a computer program product implemented on one or more computer-usable storage media (including but not limited to magnetic disk storage and optical storage, etc.) containing computer-usable program code.

[0118] The present invention is described with reference to flowcharts and / or block diagrams of methods, devices (systems), and computer program products according to embodiments of the present invention. It should be understood that each process and / or block in the flowcharts and / or block diagrams, as well as combinations of processes and / or blocks in the flowcharts and / or block diagrams, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, a special-purpose computer, an embedded processor, or other programmable data processing device to produce a machine, so that the instructions executed by the processor of the computer or other programmable data processing device generate instructions for implementing the processes in the flowcharts and / or block diagrams. Figure 1 a process or multiple processes and / or boxes Figure 1 A device that provides the functions specified in a block or multiple blocks.

[0119] These computer program instructions may also be stored in a computer readable memory that can direct a computer or other programmable data processing device to work in a specific manner, so that the instructions stored in the computer readable memory produce an article of manufacture comprising an instruction device, which implements the process Figure 1 a process or multiple processes and / or boxes Figure 1 The function specified in one or more boxes.

[0120] These computer program instructions can also be loaded onto a computer or other programmable data processing device so that a series of operational steps are executed on the computer or other programmable device to produce a computer-implemented process, thereby providing the instructions executed on the computer or other programmable device for implementing the process. Figure 1 a process or multiple processes and / or boxes Figure 1 A step that specifies a function in one or more boxes.

[0121] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the various embodiments of the present invention.

Claims

1. A method for shielding against strong seismic reflections, characterized in that: include: Calculating weighted average seismic trace data based on seismic trace data of a current seismic trace and seismic trace data of adjacent seismic traces adjacent to the current seismic trace in the seismic data; Extracting the seismic atomic parameters corresponding to the position of the strongest amplitude according to the weighted average seismic trace data; as well as Subtracting the seismic atom corresponding to the seismic atom parameter from the weighted average seismic trace data to obtain seismic trace data of the current seismic trace after removing strong reflections; The step of extracting the seismic atomic parameters corresponding to the position of the strongest amplitude according to the weighted average seismic trace data includes: Determine the vector length of the seismic atom in the atom library according to the strongest amplitude position; Taking the vector length as the inner product length, performing an inner product operation on the weighted average seismic trace data and a plurality of seismic atoms selected from the atom library; The parameter when the result of the inner product operation reaches the maximum value is used as the seismic atomic parameter.

2. The method according to claim 1, characterized in that The subtracting the seismic atoms corresponding to the seismic atom parameters from the weighted average seismic trace data comprises: The seismic atom corresponding to the parameter when the result of the inner product operation is maximized is used as the target seismic atom; Performing an inner product operation on the weighted average seismic trace data and the target seismic atom to obtain the amplitude of the target seismic atom; Multiplying the amplitude of the target seismic atom by the seismic atom parameter to obtain the energy of the target seismic atom; The energy of the target seismic atom is subtracted from the weighted average seismic trace data.

3. The method according to claim 1, characterized in that Determining the vector length of the seismic atom in the atom library according to the strongest amplitude position includes: determining a vector length of 100ms with the strongest amplitude position as the center.

4. The method according to claim 1, wherein Also includes: The above process is repeated using each seismic trace in the seismic data as the current seismic trace to obtain seismic data after strong reflections are removed.

5. The method according to any one of claims 1 to 4, characterized in that: The seismic data are seismic data that have been pre-stack processed.

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

7. A computer device comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein: When the processor executes the program, the method according to any one of claims 1 to 5 is implemented.

8. A strong seismic reflection shielding device, characterized in that: include: Data acquisition module, used to acquire seismic data; A first operation module is used to calculate weighted average seismic trace data based on seismic trace data of a current seismic trace and seismic trace data of adjacent seismic traces adjacent to the current seismic trace in the seismic data; A parameter extraction module, configured to extract the seismic atomic parameters corresponding to the position of the strongest amplitude based on the weighted average seismic trace data; as well as A second operation module is configured to subtract the seismic atom corresponding to the seismic atom parameter from the weighted average seismic trace data to obtain the seismic trace data of the current seismic trace after removing strong reflections; The parameter extraction module extracts the seismic atomic parameters corresponding to the strongest amplitude position according to the weighted average seismic trace data, including: Determine the vector length of the seismic atom in the atom library according to the strongest amplitude position; Taking the vector length as the inner product length, performing an inner product operation on the weighted average seismic trace data and a plurality of seismic atoms selected from the atom library; The parameter when the result of the inner product operation reaches the maximum value is used as the seismic atomic parameter.

9. The device according to claim 8, characterized in that: The seismic data are seismic data that have been pre-stack processed.

Images