CN118465843B - Seismic data processing method, device, medium and product for maintaining phase characteristics - Google Patents

Abstract

The invention discloses a seismic data processing method, a device, a medium and a product for maintaining phase characteristics, which relate to the field of reflection seismic data processing in geophysical exploration, wherein seismic profile data are obtained based on time-space domain seismic prestack data, and target frequency-amplitude parameters of the seismic profile data after the frequency band of a target layer is widened are determined; the time-space domain seismic prestack data are sequenced to form a common offset set; and performing amplitude value gain on frequency domain prestack data of the common offset set according to the target frequency-amplitude parameter, performing inverse Fourier transform on the gain data to obtain gain time-space domain prestack data maintaining the phase characteristic, performing fine cutting to obtain prestack result data, and then obtaining a poststack result profile through in-phase superposition. According to the invention, the frequency band of the original amplitude spectrum is expanded through the target frequency-amplitude parameter, so that the reliability and inversion effect of the pre-stack post-stack inversion result are ensured, the multi-solution of seismic geologic interpretation is reduced, and the seismic exploration precision is improved.

Description

Seismic data processing method, device, medium and product maintaining phase characteristics

Technical Field

The present invention relates to the technical field of reflection seismic data processing in geophysical exploration, and in particular to a seismic data processing method, device, medium and product for improving the resolution of reflection seismic data while maintaining phase characteristics.

Background Art

Reflection seismic exploration is one of the most accurate geophysical exploration methods. With the continuous improvement of exploration, the data-driven concept of making full use of existing prior information in the process of seismic data processing has been widely used, further improving the detection accuracy and reliability of seismic results. Among them, in the conventional wavelet processing stage, the processing parameters are extracted through the existing well information, the phase of the seismic wavelet is adjusted while the bandwidth is expanded, the wave group characteristics are improved, and the resolution is improved to a certain extent. At this time, the wave group characteristics of the seismic data match well with the characteristics of the well data. In the subsequent process of further improving the resolution, as the data bandwidth is expanded, the phase of the data often changes accordingly. Although the resolution of the data has been improved, the change in the phase characteristics will lead to an increase in the multi-solution of geological research.

Seismic exploration obtains a large amount of information about the earth's interior, which is a typical specific application of massive data and cloud computing. High-quality seismic pre-stack data that has not been stacked in phase contains massive data information in multiple dimensions, and describes the real underground information in more detail. At present, the interpretation and inversion process of seismic exploration has comprehensively shifted from post-stack inversion of small data to pre-stack inversion and post-stack inversion of massive data, requiring data processing to not only provide high-quality post-stack sections for structural interpretation, but also high-quality pre-stack data. Influenced by the habits and thinking of traditional seismic processing and interpretation processes, the main purpose of seismic exploration is to improve the imaging quality of post-stack sections and the accuracy of structural interpretation, and the quality requirements for pre-stack data are not high. At the same time, the frequency and phase characteristics of post-stack sections do not correspond to those of pre-stack data, resulting in low credibility of pre-stack inversion results, which seriously restricts the effect of seismic exploration.

Summary of the invention

The purpose of the present invention is to provide a seismic data processing method, device, medium and product that maintain phase characteristics, which can ensure the reliability of pre-stack and post-stack inversion results and the inversion effect, while reducing the multi-solution of seismic geological interpretation and improving the accuracy of seismic exploration.

To achieve the above object, the present invention provides the following solutions:

A method for processing seismic data while preserving phase characteristics, the method comprising:

Obtain seismic pre-stack data in time and space domain after dynamic correction;

Finely excise and in-phase stack the time-space domain seismic pre-stack data to obtain seismic profile data; the standard for fine excision is that the degree of stretching distortion of the data is less than a preset degree of stretching distortion;

Perform frequency-amplitude spectrum analysis on the target layer of the seismic profile data and perform frequency band widening to obtain the target frequency-amplitude parameters after the frequency band widening;

The time-space domain seismic pre-stack data are sorted according to line number, point number and offset, and the sorted time-space domain seismic pre-stack data constitute a common offset set;

Performing Fourier transform on the time-space domain prestack data of the common-offset set to obtain frequency-domain prestack data of the common-offset set;

Performing amplitude gain on the frequency domain prestack data of the common offset set according to the target frequency-amplitude parameter to obtain gained frequency domain prestack data;

Performing inverse Fourier transform on the post-gain frequency domain pre-stack data to obtain post-gain time-space domain pre-stack data with phase characteristics preserved;

The post-gain time-space domain pre-stack data with phase characteristics preserved are finely excised to obtain pre-stack result data; and the pre-stack result data are in-phase stacked to obtain a post-stack result profile.

A computer device comprises: a memory, a processor and a computer program stored in the memory and executable on the processor, wherein the processor executes the computer program to implement the steps of the above-mentioned method for processing seismic data with phase characteristics preserved.

A computer-readable storage medium stores a computer program, which, when executed by a processor, implements the steps of the above-mentioned method for processing seismic data while preserving phase characteristics.

A computer program product comprises a computer program, which, when executed by a processor, implements the steps of the above-mentioned method for processing seismic data with phase characteristics preserved.

According to the specific embodiments provided by the present invention, the present invention discloses the following technical effects:

The present invention provides a seismic data processing method, device, medium and product that maintain phase characteristics. In order to fully explore the multi-dimensional internal earth information contained in the massive seismic data, in the data processing process, in the stage of improving the resolution after the well-driven wavelet processing, the present invention transforms the data into the frequency domain, improves the resolution by editing the amplitude spectrum, and then returns to the time and space domain through the inverse Fourier transform. The entire phase spectrum is not affected. Compared with many other existing methods for improving the resolution, the non-zero phase inverse filtering is performed directly in the time and space domain, which changes both the amplitude spectrum and the phase spectrum. The processing process of the present invention maintains the phase characteristics. Therefore, the data processing process of the present invention can simultaneously improve the resolution of the post-stack result profile and the pre-stack result data under the premise of keeping the phase characteristics of the seismic data unchanged, so that the frequency characteristics and phase characteristics of the two are matched with each other, while ensuring the reliability of the pre-stack and post-stack inversion results and the inversion effect, reduce the multi-solution of the seismic geological interpretation, and improve the accuracy of seismic exploration.

BRIEF DESCRIPTION OF THE DRAWINGS

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

FIG1 is a schematic flow chart of a method for processing seismic data for preserving phase characteristics provided in Embodiment 1 of the present invention;

FIG2 is a schematic diagram of an original frequency-amplitude spectrum and a target frequency-amplitude spectrum provided in Example 1 of the present invention;

FIG3 is a schematic diagram of a spectrum before and after resolution improvement provided by Embodiment 1 of the present invention;

FIG4 is a schematic cross-sectional view of seismic results before and after resolution improvement provided by Example 1 of the present invention;

FIG. 5 is a diagram showing the internal structure of a computer device.

DETAILED DESCRIPTION

The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

The purpose of the present invention is to provide a seismic data processing method, device, medium and product that maintain phase characteristics, which can ensure the reliability of pre-stack and post-stack inversion results and the inversion effect, while reducing the multi-solution of seismic geological interpretation and improving the accuracy of seismic exploration.

In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, the present invention is further described in detail below with reference to the accompanying drawings and specific embodiments.

Example 1

As shown in FIG1 , a method for processing seismic data for preserving phase characteristics in this embodiment includes:

S1: Obtain seismic pre-stack data in the time and space domain after dynamic correction.

The acquired data is seismic pre-stack time-space domain data that needs to further improve the resolution after well-driven wavelet processing, and the data has been processed by dynamic correction, requiring the phase axis to be flattened.

S2: finely excise and in-phase stack the time-space domain seismic pre-stack data to obtain seismic profile data.

The standard for fine excision is that the degree of stretching distortion of the data is less than the preset degree of stretching distortion, that is, there is no obvious stretching distortion.

S3: Perform frequency-amplitude spectrum analysis on the target layer of the seismic profile data and perform frequency band widening to obtain target frequency-amplitude parameters after frequency band widening.

Wherein, step S3 specifically includes:

(3-1) Perform frequency-amplitude spectrum analysis on the target layer of the seismic profile data to obtain the original amplitude spectrum. As shown in Figure 2, the black solid line is the original amplitude spectrum obtained from the data itself.

(3-2) According to the actual needs of interpretation and inversion, the original amplitude spectrum is band-expanded to obtain a target amplitude spectrum, such as the target amplitude spectrum shown by the dotted line in Figure 2. In the figure, the ordinate A represents the amplitude, and the abscissa f represents the frequency.

(3-3) The low frequency, high frequency, main frequency and amplitude corresponding to each frequency band of the target amplitude spectrum are taken and recorded as , , , , , , taking the above six values to obtain the target frequency-amplitude parameters.

S4: sorting the space-time domain seismic pre-stack data according to line number, point number and offset, and the sorted space-time domain seismic pre-stack data constitute a common offset set.

S5: Performing Fourier transform on the pre-stack data in the time and space domain of the common-offset set to obtain pre-stack data in the frequency domain of the common-offset set.

S6: performing amplitude gain on the frequency domain prestack data of the common-shot offset set according to the target frequency-amplitude parameter to obtain gained frequency domain prestack data, i.e., high-resolution frequency domain prestack data; wherein, high-resolution frequency domain prestack data refers to frequency domain prestack data with improved resolution.

After obtaining the target frequency-amplitude parameters, the amplitude values of the low frequency band, high frequency band and main frequency of the data are relatively increased in the frequency domain to widen the frequency band and move the main frequency toward the high frequency direction, thereby obtaining high-resolution frequency domain pre-stack data. In other words, the amplitudes of the corresponding frequency bands in the frequency domain pre-stack data of the common offset set are subjected to gain processing according to the low frequency, high frequency, main frequency and amplitudes corresponding to each frequency band of the target amplitude spectrum, thereby obtaining the frequency domain pre-stack data after gain.

S7: performing inverse Fourier transform on the gained frequency domain pre-stack data to obtain gained time-space domain pre-stack data with phase characteristics preserved, that is, high-resolution time-space domain pre-stack data with phase characteristics preserved.

The Fourier transform and inverse Fourier transform used in the present invention adopt the fast discrete Fourier transform method, which regards a finite length seismic signal as an infinite length discrete time series that is zero outside the recording range, and performs Fourier transform, which can complete the conversion between the time domain signal and the data domain of the sinusoidal wave signal of multiple frequencies. Time Series The Fourier transform of is:

, .

in, .

The inverse Fourier transform is:

, .

Where d represents a specific observation point, x(d) represents the observation value at a specific observation point, and j represents an imaginary unit.

S8: finely excise the post-gain spatiotemporal pre-stack data that maintains the phase characteristics, with the excision criterion being no obvious stretching distortion, to obtain pre-stack result data; and perform in-phase stacking on the pre-stack result data to obtain a post-stack result profile.

The solution of this embodiment has the following advantages:

(1) After well drive processing, the phase characteristics and wave group characteristics of seismic data are relatively clear and do not want to change further, but the resolution ability still needs to be further improved. The present invention provides an effective technical solution for improving the resolution, which maintains the phase characteristics of the seismic data while improving the resolution.

(2) The resolution enhancement scheme provided by the present invention is based on the quality of the actual seismic data itself. According to the actual frequency-amplitude spectrum of different target layers in different regions, targeted data processing is carried out. The enhanced frequency band range is not generated out of thin air, and the result is highly reliable. The target frequency-amplitude parameters are set according to the actual data conditions and are not limited by the reflection seismic work area and seismic geological conditions.

(3) In the present invention, the target frequency-amplitude parameter setting for improving the resolution is carried out interactively according to the spectrum shape and the reading value, which is easy to operate and allows accurate and real-time adjustment according to the actual needs of geological interpretation and inversion within the maximum frequency band of the data itself. Therefore, it can not only fully tap the potential of frequency information contained in the seismic data, but also achieve the most detailed characterization of the internal structure and external shape of different underground geological bodies, and accurately guide geological exploration.

(4) The technical solution provided by the present invention is applied to both post-stack profile data and pre-stack data, thereby achieving the unification of pre-stack and post-stack data characteristics and ensuring the simultaneous inversion effect and reliability of pre-stack and post-stack data.

The following uses actual seismic data from a certain area in the east as an example to illustrate the seismic data processing method for improving resolution of the present invention. In Figure 3, part (a) is the spectrum analysis for the target layer segment, that is, the spectrum before improving the resolution. From the spectrum point of view, its frequency band range is about 9~30Hz, and the main frequency is about 20Hz. The actual spectrum of the seismic data is taken as a premise. Based on the original frequency band, the target parameters for improving the resolution processing are formulated, and the low frequency, high frequency, main frequency and corresponding amplitude of the target amplitude spectrum are taken and recorded as =7Hz, =45Hz, =25Hz, =0.8, =0.8, =1, take the above six values to get the target frequency-amplitude parameters, and after performing amplitude gain on each frequency band in the frequency domain, perform spectrum analysis on the obtained data. As shown in Figure 3, part (b) is the spectrum after improving the resolution. The spectrum of the target layer is broadened to 6~45Hz, and the main frequency moves to the high frequency band to about 25Hz. In Figure 4, part (a) is the seismic profile before improving the resolution, and part (b) is the seismic profile after improving the resolution. Compared with Figure 4 (a), Figure 4 (b) has improved visual resolution, while the strength relationship of the event axis, wave group characteristics and phase characteristics of the two are consistent.

In this embodiment, since high-quality pre-stack data and result profile data that can be used for pre-stack inversion are obtained at the same time, and the processing process and quality characteristics of the two are the same, the unification of pre-stack and post-stack data characteristics is achieved, and the reliability of pre-stack and post-stack inversion effects and inversion results is ensured, while reducing the differences in seismic data processing and interpretation, and improving the seismic exploration effect of complex structures in complex areas.

Example 2

A computer device includes: a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor executes the computer program to implement the steps of a seismic data processing method for preserving phase characteristics in Example 1.

Example 3

A computer-readable storage medium stores a computer program, which, when executed by a processor, implements the steps of a seismic data processing method for preserving phase characteristics in Example 1.

Example 4

A computer program product includes a computer program, which, when executed by a processor, implements the steps of a seismic data processing method for preserving phase characteristics in embodiment 1.

Example 5

A computer device, which can be a database, and its internal structure diagram can be shown in Figure 5. The computer device includes a processor, a memory, an input/output interface (Input/Output, referred to as I/O) and a communication interface. Among them, the processor, the memory and the input/output interface are connected through a system bus, and the communication interface is connected to the system bus through the input/output interface. Among them, the processor of the computer device is used to provide computing and control capabilities. The memory of the computer device includes a non-volatile storage medium and an internal memory. The non-volatile storage medium stores an operating system, a computer program and a database. The internal memory provides an environment for the operation of the operating system and the computer program in the non-volatile storage medium. The database of the computer device is used to store pending transactions. The input/output interface of the computer device is used to exchange information between the processor and an external device. The communication interface of the computer device is used to communicate with an external terminal through a network connection. When the computer program is executed by the processor, a seismic data processing method for maintaining phase characteristics in Example 1 is implemented.

It should be noted that the object information (including but not limited to object device information, object personal information, etc.) and data (including but not limited to data used for analysis, stored data, displayed data, etc.) involved in the present invention are all information and data authorized by the object or fully authorized by all parties, and the collection, use and processing of relevant data must comply with relevant laws, regulations and standards of relevant countries and regions.

Those skilled in the art can understand that all or part of the processes in the above-mentioned embodiments can be completed by instructing the relevant hardware through a computer program, and the computer program can be stored in a non-volatile computer-readable storage medium. When the computer program is executed, it can include the processes of the embodiments of the above-mentioned methods. Among them, any reference to the memory, database or other medium used in the embodiments provided by the present invention can include at least one of non-volatile and volatile memory. Non-volatile memory can include read-only memory (ROM), magnetic tape, floppy disk, flash memory, optical memory, high-density embedded non-volatile memory, resistive random access memory (ReRAM), magnetoresistive random access memory (MRAM), ferroelectric random access memory (FRAM), phase change memory (PCM), graphene memory, etc. Volatile memory can include random access memory (RAM) or external cache memory, etc. As an illustration and not limitation, RAM can be in various forms, such as static random access memory (SRAM) or dynamic random access memory (DRAM). The database involved in each embodiment provided by the present invention may include at least one of a relational database and a non-relational database. Non-relational databases may include distributed databases based on blockchains, etc., but are not limited to this. The processor involved in each embodiment provided by the present invention may be a general-purpose processor, a central processing unit, a graphics processor, a digital signal processor, a programmable logic device, a data processing logic device based on quantum computing, etc., but are not limited to this.

The technical features of the above embodiments may be combined arbitrarily. To make the description concise, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

The principles and implementation methods of the present invention are described in this article using specific examples. The description of the above embodiments is only used to help understand the method and core idea of the present invention. At the same time, for those skilled in the art, according to the idea of the present invention, there will be changes in the specific implementation methods and application scope. In summary, the content of this specification should not be understood as limiting the present invention.

Claims (5)

1. A method for processing seismic data with phase characteristics preserved, comprising: Obtain seismic pre-stack data in time and space domain after dynamic correction; Finely excise and in-phase stack the time-space domain seismic pre-stack data to obtain seismic profile data; the standard for fine excision is that the degree of stretching distortion of the data is less than a preset degree of stretching distortion; Perform frequency-amplitude spectrum analysis on the target layer of the seismic profile data and perform frequency band widening to obtain the target frequency-amplitude parameters after the frequency band widening; The time-space domain seismic pre-stack data are sorted according to line number, point number and offset, and the sorted time-space domain seismic pre-stack data constitute a common offset set; Performing Fourier transform on the time-space domain prestack data of the common-offset set to obtain frequency-domain prestack data of the common-offset set; Performing amplitude gain on the frequency domain prestack data of the common offset set according to the target frequency-amplitude parameter to obtain gained frequency domain prestack data; Performing inverse Fourier transform on the post-gain frequency domain pre-stack data to obtain post-gain time-space domain pre-stack data with phase characteristics preserved; Finely excise the post-gain spatiotemporal pre-stack data that maintains the phase characteristics to obtain pre-stack result data; perform in-phase stacking on the pre-stack result data to obtain a post-stack result profile; Perform frequency-amplitude spectrum analysis on the target layer of the seismic profile data and perform frequency band widening to obtain the target frequency-amplitude parameters after frequency band widening, including: Perform frequency-amplitude spectrum analysis on the target layer of the seismic profile data to obtain the original amplitude spectrum; According to the actual needs of interpretation and inversion, the original amplitude spectrum is band-expanded to obtain a target amplitude spectrum; The low frequency, high frequency, main frequency and amplitude corresponding to each frequency band of the target amplitude spectrum are taken to obtain the target frequency-amplitude parameters. 2. A method for processing seismic data for preserving phase characteristics according to claim 1, characterized in that the frequency domain prestack data of the common offset set is subjected to amplitude gain according to the target frequency-amplitude parameter, specifically comprising: According to the low frequency, high frequency, main frequency and amplitude corresponding to each frequency band of the target amplitude spectrum, gain processing is performed on the amplitude of each frequency band corresponding to the frequency domain prestack data of the common offset set to obtain the gained frequency domain prestack data. 3. A computer device comprising: a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor executes the computer program to implement the steps of a seismic data processing method for preserving phase characteristics as described in any one of claims 1-2. 4. A computer-readable storage medium having a computer program stored thereon, characterized in that when the computer program is executed by a processor, the steps of a seismic data processing method for preserving phase characteristics as described in any one of claims 1-2 are implemented. 5. A computer program product, comprising a computer program, characterized in that when the computer program is executed by a processor, the steps of a seismic data processing method for preserving phase characteristics described in any one of claims 1-2 are implemented.