Detailed Description
According to the method, the system and the electronic equipment for positioning the seismic source based on the three-dimensional seismic reflection data, the technical problem that the positioning accuracy is low under a complex geological structure due to the fact that the seismic source is positioned only by means of direct waves and the consideration of the propagation characteristics and the reflection characteristics of seismic waves is insufficient in the prior art is solved, and the technical effects of improving the positioning accuracy of the seismic source and enhancing the adaptability to complex geological conditions are achieved.
An embodiment of the present application provides a method for positioning a seismic source based on three-dimensional seismic reflection data, as shown in fig. 1, the method including:
And S1, acquiring three-dimensional geological reflection data by arranging a detection point array in a target research area, wherein the three-dimensional geological reflection data comprises a plurality of seismic trace data of a plurality of detection points in the detection point array.
Specifically, the target study area refers to a specific area where geological exploration or seismic monitoring is performed, such as a coal mine production area, a geological fault zone, etc. In a target research area, a plurality of detection points are selected according to a certain interval and a certain rule, and detection equipment such as geophones and the like are arranged to form a detection point array. The geophone of each detection point is responsible for collecting seismic wave signals, recording information such as arrival time of the seismic wave, azimuth or angle of the reflected wave, intensity of the reflected wave and the like, combining the information to form seismic trace data of each detection point, and the seismic trace data of all the detection points form three-dimensional geological reflection data.
By acquiring three-dimensional geological reflection data, geological reflection conditions are reflected from a three-dimensional space angle, and a most basic data source is provided for the whole seismic source positioning.
And S2, performing initial positioning of a seismic source according to the three-dimensional geological reflection data to obtain a first seismic source position.
Specifically, the three-dimensional geological reflection data acquired in the step S1 are processed by adopting a positioning algorithm, and the position of a seismic source is estimated preliminarily to obtain the position of a first seismic source. For example, using a time-of-flight pick-up method, the location of the source is initially calculated from the time differences between arrival of the seismic waves at each of the detection points, in combination with a known wave velocity model.
By means of initial positioning of the seismic source, a relatively rough seismic source position estimation is obtained, an initial searching range is provided for subsequent accurate positioning, and the efficiency of subsequent positioning is improved.
And S3, extracting a reflected wave time series array mapped to the detection point array from the three-dimensional geological reflection data.
Specifically, the reflected wave time sequence array is a data array which is extracted from three-dimensional geological reflected data and corresponds to the detection point array and is used for reflecting the time sequence condition of the reflected wave received by different detection points. And (3) screening reflected wave time information corresponding to the detection point array from the three-dimensional geological reflection data acquired in the step (S1) through a data extraction algorithm, and sorting the information into a reflected wave time sequence array. These time series arrays of reflected waves provide a richer data type for subsequent correlation analysis, helping to more fully understand the relevant information of the seismic source.
And S4, taking the first seismic source position as an optimization starting point, and performing correlation analysis on the three-dimensional geological reflection data and the reflected wave time sequence array to obtain seismic source space-time parameters.
Specifically, with the first source position obtained in step S2 as a starting point, a correlation analysis algorithm (for example, a correlation analysis algorithm based on a least square method) is used to comprehensively analyze three-dimensional geological reflection data and a reflected wave time series array. And (3) determining the position information of the seismic source in space and the related information (such as the time range of the seismic source activity) on a time axis by analyzing the reflection condition of the seismic waves at different detection points, the time sequence and other information, and obtaining the time-space parameters of the seismic source.
Through association analysis, the propagation characteristics and reflection characteristics of seismic waves in complex geological structures are comprehensively considered, so that the time-space parameters of the seismic source are obtained, and the accuracy of seismic source positioning is further improved.
And S5, pre-constructing a three-dimensional seismic wave velocity model.
In particular, different subsurface media (e.g., rock type, soil type, etc.) differ in propagation velocity of seismic waves, and a three-dimensional seismic wave velocity model may detail the seismic wave velocity distribution in the subsurface media. The three-dimensional seismic wave velocity model is constructed by modeling software (such as Matlab and the like) by utilizing the existing geological exploration data (such as rock type distribution of different stratum and the like) and the theoretical knowledge of seismic wave propagation. The model describes the speed distribution condition of the seismic waves in the underground medium in detail, provides important constraint conditions for inversion iteration in the step S6, can guide calculation to be conducted towards the direction conforming to the propagation rule of the seismic waves of the underground medium, and improves the accuracy and efficiency of iteration.
And S6, taking the seismic source space-time parameters as initial conditions, taking the three-dimensional seismic wave velocity model as iteration constraint to carry out inversion iteration until reaching a preset convergence condition, and outputting a target seismic source position.
Specifically, with the source space-time parameter obtained in step S4 as an initial condition, and the three-dimensional seismic wave velocity model constructed in step S5 as an iteration constraint, an inversion iterative algorithm (such as gaussian-newton method) is used for calculation. And (3) adjusting the calculation of the position of the seismic source according to the model constraint every iteration until the change of the calculation result is smaller than a preset convergence condition (such as the change of the position is smaller than a certain set value), and outputting the position of the target seismic source. By iterative calculation, under the constraint of a three-dimensional seismic wave velocity model, the position of a seismic source is gradually and accurately obtained, and the position of a target seismic source meeting the accuracy requirement is finally obtained, so that the positioning accuracy is ensured, and the calculation efficiency is also ensured.
Further, step S2 of the embodiment of the present application includes:
and S21, performing geological data coverage analysis on the target research area, and performing data calling according to an analysis result to obtain geological priori information.
And S22, constructing a seismic wave propagation model according to the geological priori information.
And S23, loading the three-dimensional geological reflection data to the seismic wave propagation model, and performing initial positioning of a seismic source through simulation matching to obtain a first seismic source position.
Specifically, the geological prior information is prior knowledge of the geological features and parameters of the target region of investigation based on existing geological data and analysis results. And collecting the existing geological data of the target research area, such as the past geological exploration report, geological research paper and the like. The existing geological related data (such as data of stratum structure, rock type distribution and the like) of the target research area are comprehensively and completely analyzed, and the coverage condition of the data on the target research area, such as whether the whole area is covered, the data integrity of different strata and the like, is analyzed. According to the analysis result, related data such as rock density data, stratum thickness data and the like of a certain stratum are called from the existing geological data, geological priori information is obtained by integrating the called data, basic data support is provided for subsequent construction of a seismic wave propagation model, and accuracy and reliability of the model are improved. In implementations, geological Information System (GIS) software may be used to manage and analyze the geological data, with database query tools for data recall. For example, in a coal mine production area, geological survey reports, formation maps and past seismic monitoring data for the area are collected. The data are subjected to coverage analysis through GIS software, so that the data in certain areas are found to be complete, and the data in other areas are missing. And calling available geological data, such as thickness, depth, lithology and the like of the coal layer, according to the analysis result to form geological priori information.
The seismic wave propagation model is a mathematical model describing the propagation characteristics of seismic waves (including wave velocity, attenuation, etc.) within a target investigation region. Characteristics of the subsurface medium (such as medium types, densities, etc. of different strata) are determined by using the obtained geological priori information. A model capable of reflecting the propagation rule of the seismic waves in the medium, namely a seismic wave propagation model, is constructed by utilizing a seismic wave propagation theory, such as a wave equation, and combining geological modeling software. Specifically, professional geological modeling software such as Petrel, GOCAD and the like can be used, and different medium layers in the model and corresponding physical parameters such as wave speed, density and the like are defined according to the distribution of stratum and geological parameters. For example, in a coal mine production area, according to geological priori information, the area is known to be mainly composed of different lithologies such as coal seams, sandstones, mudstones and the like. When constructing a seismic wave propagation model, the lithology layers are respectively defined as different medium layers, and corresponding wave velocity and density values are given. For example, the wave velocity of the coal bed is 3000m/s, the wave velocity of the sandstone is 3500m/s, and the wave velocity of the mudstone is 2800m/s. By constructing a seismic wave propagation model based on geological priori information, the propagation characteristics of seismic waves in a target research area can be reflected more accurately, and a theoretical frame is provided for subsequent seismic source initial positioning.
And loading the three-dimensional geological reflection data acquired in the step S1 into the constructed seismic wave propagation model. Different source positions are then assumed in the model, and the propagation of the seismic waves to the various detection points (e.g., arrival times, intensities, etc.) at these assumed source positions is calculated from the model. And comparing and analyzing the actually observed three-dimensional geological reflection data with theoretical data in the seismic wave propagation model, and continuously adjusting the assumed source position until the seismic wave propagation condition calculated by the model is matched with the actual three-dimensional geological reflection data (for example, the time difference reaching each detection point is within an allowable error range), wherein the determined source position is the first source position. Illustratively, in a coal mine production area, the acquired three-dimensional geological reflection data is loaded into a seismic wave propagation model. And simulating the propagation of the seismic wave by a finite difference method to obtain theoretical reflected wave data. Comparing the simulated reflected wave data with the actually collected data, the difference between the simulated reflected wave data and the actually collected data is found to be minimum when the position of the seismic source is adjusted to a certain coordinate point, so that the coordinate point is determined to be the first seismic source position. By means of simulation matching, the first seismic source position is obtained by utilizing three-dimensional geological reflection data and a seismic wave propagation model, an initial reference point is provided for follow-up accurate seismic source positioning, the searching range is reduced, the positioning efficiency is improved, and a foundation is provided for follow-up fine positioning.
Further, step S4 of the embodiment of the present application includes:
and S41, outputting a seismic wave delay time array by performing seismic wave delay analysis on the reflected wave time sequence array.
And step S42, carrying out waveform characteristic identification on the three-dimensional seismic reflection data to obtain a seismic reflection wave characteristic array.
And S43, performing source position iterative adjustment on the first source position in the seismic wave propagation model by referring to the seismic wave delay time array and the seismic reflection wave characteristic array to obtain source space-time parameters, wherein the source space-time parameters comprise a second source position, a seismic wave propagation path and seismic occurrence time.
Specifically, the seismic delay time array is a data set containing the seismic delay times between a plurality of detection points. And acquiring data of a reflected wave time series array, and analyzing the geological condition of a seismic wave propagation theory and a target research area according to each time data in the array. The delay time of the seismic wave at each detection point relative to a certain reference time is calculated by considering the factors such as the change of the propagation speed of the seismic wave in different strata (such as the propagation from the sandstone stratum to the shale stratum), the length of the propagation path and the like, and the calculated delay time is arranged according to the sequence of the detection points to form a seismic wave delay time array. Through the earthquake wave delay analysis, the propagation delay condition of earthquake waves between different detection points is obtained, time difference information is provided for subsequent earthquake source position iteration adjustment, and the earthquake source position can be accurately determined.
The array of seismic reflection wave features is a data set of seismic reflection wave features comprising a plurality of detection points. Seismic wave waveform data for each detection point is extracted from the three-dimensional seismic reflection data. These waveform data are then analyzed using signal processing techniques, such as fourier transforms, etc. The characteristics of the seismic reflection wave of each detection point are determined by analyzing amplitude variation, frequency components, phase conditions and the like of the waveform, and the characteristics are arranged according to the sequence of the detection points to form a seismic reflection wave characteristic array. In actual practice, signal processing and pattern recognition software, such as the correlation library in MATLAB, python, may be used to extract and analyze waveform features. Through waveform characteristic identification, characteristic information of the seismic reflection wave is obtained, waveform characteristic basis is provided for subsequent seismic source position iterative adjustment, and the relationship between the reflection wave and the seismic source position can be more accurately matched and identified.
The first source location is input into the seismic wave propagation model as an initial assumption. Based on the information in the seismic delay time array and the seismic reflection wave characteristic array, differences between the simulated seismic wave propagation results and the actual data at the assumed source position are calculated. Based on these differences, the source position assumptions are then adjusted, calculated and compared again. This process is repeated, i.e., iterated, over time. In the iterative process, along with the adjustment of the position of the seismic source, the propagation path (the propagation track of the seismic wave in the model) and the occurrence time of the seismic wave (the information such as the time when the seismic wave reaches each detection point and the propagation path is combined) are determined simultaneously. When iteration is performed until a certain convergence condition is met (for example, the amplitude of the adjustment of the position of the seismic source is smaller than a certain set value), the obtained position of the seismic source is the second position of the seismic source, and the determined information such as the position of the seismic source, the propagation path of the seismic wave, the occurrence time of the seismic wave and the like forms a space-time parameter of the seismic source. By means of the iteration adjustment of the seismic source position, the propagation characteristic and the reflection characteristic of seismic waves in a complex geological structure are considered, more accurate seismic source space-time parameters are obtained, the accuracy of seismic source positioning is further improved, and more accurate initial conditions are provided for subsequent inversion iteration.
Further, step S21 of the embodiment of the present application includes:
and step S211, taking the target research area as a retrieval constraint, and retrieving and calling area geological data, wherein the area geological data comprises a plurality of geological parameter information of a plurality of area strata, and the geological parameter information comprises medium density, longitudinal wave speed and constant wave speed.
And S212, carrying out coverage integrity analysis on the target research area according to the plurality of regional strata to obtain a deviation stratum interval.
And S213, interactively obtaining target geological conditions of the target research area, and matching to obtain priori geological data by taking the target geological conditions and the deviation stratum interval as matching conditions.
Step S214, fusing the priori geological data to the geological parameter information according to the deviation stratum interval to serve as the geological priori information.
Specifically, the geological data database management system is utilized, the geographical position, the range and other information of the target research area are used as search conditions, geological data containing the area or the geological data related to the area are searched in the database, the data contain geological parameter information of a plurality of regional strata, such as data of medium density, longitudinal wave speed, transverse wave speed and the like of different strata, and an original geological data base is provided for subsequent analysis.
And carding stratum information in the retrieved regional geological data. And comparing stratum structures which are actually contained in the target research area, checking the coverage condition of each stratum in the data, and judging whether the geological data of some stratum is missing or incomplete. For those formations whose coverage is incomplete or whose geological parameters are not expected to be in compliance with the target study area, the extent of which within the target study area is determined, forming a deviation formation interval. And the integrity condition of stratum data in the target research area is defined, a stratum interval with problems is found, the geological data can be purposefully supplemented or corrected in the subsequent steps, and the accuracy of geological priori information is improved.
And acquiring target geological conditions such as stratum structure and lithology of a target research area through an interactive interface or an expert system. And then, screening and matching in the regional geological data by taking the target geological conditions and the deviation stratum interval as matching conditions, and finding out geological data which meets the target geological conditions and can make up for the deficiency or deficiency of the data of the deviation stratum interval as priori geological data. The target geological conditions are obtained through interaction, and the target geological conditions are used as matching conditions, so that priori geological data which is matched with the target research area best is obtained, and the pertinence and the accuracy of the geological priori information are improved.
And determining the position relation of the priori geological data in the target research area according to the deviation stratum interval. And fusing the related data in the prior geological data into a plurality of geological parameter information according to the corresponding stratum relation, for example, if special medium density data related to a certain deviation stratum in the prior geological data is related, updating the special medium density data to medium density items in the geological parameter information of the corresponding stratum, so that geological prior information is formed. The obtained geological priori information integrates various geological data, more accurately and completely reflects the geological condition of a target research area, provides a more reliable data base for constructing a seismic wave propagation model, and is beneficial to improving the accuracy of seismic source positioning.
Further, step S22 of the embodiment of the present application includes:
and S221, extracting stratum distribution information of the target research area from the regional geological data.
And step S222, constructing a stratum distribution model according to the stratum distribution information.
Step S223, presetting a grid scale to grid the stratum distribution model to obtain a plurality of three-dimensional grid units.
And step 224, according to stratum sources of the plurality of three-dimensional grid units, mapping and scheduling geological parameter values from the geological priori information to carry out grid filling, and completing construction of the seismic wave propagation model.
Specifically, the formation distribution information refers to information about the arrangement, thickness, lithology, etc. of the formations in the target study area, and is used to describe the distribution state of the formations in space. And screening stratum information parts related to the target research area from the acquired regional geological data. For example, information such as thickness of each layer of stratum, sequence of upper and lower layers and the like is read from a stratum profile in a geological report, lithology of the stratum is determined from a text description, and stratum distribution information of a target research area is obtained. The stratum distribution information is key content for describing the geological structure of the target research area, and provides basic data for constructing a stratum distribution model.
According to the extracted stratum distribution information, a stratum distribution model is built by utilizing a three-dimensional modeling technology, and the stratum distribution model is used for intuitively representing the distribution condition of stratum in a three-dimensional space in a target research area and is an intermediate model for building a seismic wave propagation model. If the formation distribution information indicates that there are multiple layers of formations and the thickness and spatial location of each layer are different, the formation geometry is constructed in three-dimensional space from the information. For example, information such as the interface, thickness, etc. of different strata is input using Computer Aided Design (CAD) software or specialized geologic modeling software to generate a strata distribution model.
A suitable grid scale is preset, such as 10m x 5 m. And then dividing the stratum distribution model according to a set grid scale by using modeling software to form a plurality of three-dimensional grid units, wherein each three-dimensional grid unit has own space position and size. By converting the complex stratum distribution into a plurality of small three-dimensional grid cells, subsequent operations such as numerical calculation, geological parameter assignment and the like are facilitated, and the operability and calculation efficiency of the model are improved.
For each three-dimensional grid cell, its stratigraphic source (i.e., the stratigraphic layer to which the grid cell corresponds) is determined. And then according to the stratum source, searching the corresponding geological parameter values from the geological priori information, for example, if the grid unit A belongs to a certain sandstone stratum, then searching the parameter values such as the medium density, the longitudinal wave speed and the like of the sandstone stratum in the geological priori information. And giving the searched geological parameter values to the grid unit, and performing grid filling operation on all three-dimensional grid units, thereby completing the construction of the seismic wave propagation model. Through mapping scheduling of geological parameter values, each three-dimensional grid cell is endowed with proper geological parameter values, so that a seismic wave propagation model can accurately reflect physical characteristics of underground media in a target research area, and a reliable model foundation is provided for subsequent seismic source positioning.
Further, step S3 of the embodiment of the present application includes:
And S31, detecting and covering analysis is carried out on the target research area, and the detection point array is output.
And S32, collecting seismic wave reflection signals through a first seismic detector arranged at a first detection point to obtain first seismic channel data, wherein the first seismic channel data comprises a first reflected wave time sequence, a first reflected wave position coordinate and a first reflected wave amplitude.
And step S33, the first detection point transmits the first seismic channel data to a data processing center through a wireless communication network.
And step S34, and the like, the data processing center receives the plurality of seismic channel data.
And S35, after the data processing center extracts a plurality of reflected wave time sequences from the plurality of seismic trace data, structuring the plurality of reflected wave time sequences according to a plurality of reflected wave position coordinates to obtain the reflected wave time sequence array.
Specifically, geographic Information System (GIS) software is used for detecting coverage analysis of a target research area, the layout of a detection point array is determined, detection points can cover the whole research area, detection blind areas are avoided, complete space coverage is provided for subsequent seismic wave reflection signal acquisition, and data integrity is improved.
The first detection point is any detection point in the detection point array, and is used as a starting point for collecting seismic wave reflection signals (the first detection point is taken as an example, and the subsequent other detection point collecting processes are similar). And arranging a first geophone at the first detection point, wherein the geophone can sense a signal of the reflected wave after the seismic wave propagates to the area and is reflected. The geophone records information such as time, position coordinates (i.e., azimuth and amplitude of the reflected wave) and the like of the reflected wave to form first seismic trace data. For example, a sensor in the geophone converts the reflected wave into an electrical signal according to a physical change (such as vibration, magnetic field change, etc.) caused by the reflected wave, and a digital signal containing information such as time, angle, amplitude, etc. is obtained after processing, namely the first seismic trace data.
The first detection point sends the acquired first seismic trace data out through a preset wireless communication network through a data acquisition device connected with the first seismic detector. For example, with Wi-Fi network communication, the data acquisition device may package and encode data according to a Wi-Fi communication protocol, and then send the data to a Wi-Fi router, and then transmit the data to a data processing center through a network.
According to the data acquisition mode of the first detection point, other detection points acquire seismic reflection signals and transmit the seismic channel data of the seismic reflection signals to a data processing center through a wireless communication network. The data processing center continuously receives the seismic channel data from each detection point, and finally a plurality of seismic channel data are obtained.
The data processing center extracts a reflected wave time sequence in each seismic trace data from the received plurality of seismic trace data. And then carrying out structuring treatment on the reflected wave time sequences according to the reflected wave position coordinates in each seismic trace data. For example, if the reflected wave time series is arranged in the azimuth order of the reflected waves, an ordered array, that is, a reflected wave time series array is formed. The time series array of the reflected waves is convenient for carrying out overall analysis on the reflection condition of the seismic waves in the target research area, and provides an ordered data basis for subsequent operations such as seismic wave delay analysis and the like.
Further, step S43 of the embodiment of the present application includes:
and step S431, after the seismic wave propagation model locates the first seismic source position, data acquisition of a seismic wave propagation simulation process is carried out, and theoretical reflected wave data are obtained.
And step S432, carrying out waveform characteristic identification on the theoretical reflection wave data to obtain a theoretical reflection wave characteristic array.
And S433, extracting a theoretical time series array mapped to the detection point array from the theoretical reflected wave data.
And step S434, performing source position adjustment on the first source position according to the matching comparison results of the seismic wave delay time array, the seismic reflection wave characteristic array, the theoretical reflection wave characteristic array and the theoretical time sequence array until the source space-time parameters are obtained through iterative adjustment.
Specifically, the theoretical reflected wave data is data acquired by performing a seismic wave propagation simulation process according to the first source position in the seismic wave propagation model, and reflects the situation of theoretical seismic wave reflection under the assumed source position. In the seismic wave propagation model, a first source location is set as a source point. The propagation of the seismic wave from the source is then simulated based on the set geologic parameters (e.g., dielectric density of the formation, wave velocity, etc.) in the model and the initial excitation conditions of the source (e.g., source energy, source type, etc.). During the propagation process, when the seismic waves encounter different stratum interfaces to reflect, data related to the reflected waves, such as the intensity, arrival time and the like of the reflected waves, are collected, and the data are combined to form theoretical reflected wave data.
The theoretical reflected wave characteristic array is an array which is obtained by carrying out waveform characteristic identification on theoretical reflected wave data and contains various waveform characteristic (such as amplitude, frequency, phase and the like) information of the theoretical reflected wave. And carrying out waveform characteristic identification on the theoretical reflected wave data. And adopting a signal processing technology, for example, carrying out Fourier transformation on theoretical reflected wave data, analyzing frequency components of the theoretical reflected wave data, and simultaneously determining the characteristics of amplitude, phase and the like of the waveform. And arranging waveform characteristic information of the theoretical reflected waves corresponding to each detection point according to a certain sequence to form a theoretical reflected wave characteristic array. The theoretical reflection wave characteristic array can reflect the waveform characteristics of the theoretical seismic waves at different detection points, is beneficial to comparing with the actual seismic reflection wave characteristic array, and finds out the difference, so that a basis is provided for seismic source position adjustment.
And screening the arrival time information of the reflected wave related to each detection point from the theoretical reflected wave data. These time information are arranged in the order of the detection points in the detection point array to form a theoretical time series array. For example, if there are 5 detection points in the detection point array, the time data of the theoretical reflected wave reaching each detection point is extracted according to the sequence of the 5 detection points, so as to form a theoretical time sequence array.
Firstly, matching comparison is carried out on a seismic wave delay time array, a seismic reflection wave characteristic array, a theoretical reflection wave characteristic array and a theoretical time sequence array. The method comprises the steps of comparing time differences of corresponding detection points in an actual seismic wave delay time array and a theoretical time sequence array, and comparing waveform characteristic differences of corresponding detection points in an actual seismic reflection wave characteristic array and a theoretical reflection wave characteristic array. Based on these differences, the first source location is adjusted. Then, seismic wave propagation simulation is carried out again, and the steps are repeated and iterated continuously. When a certain convergence condition (such as that the amplitude of the seismic source position adjustment is smaller than a certain set value or the difference between the data arrays is smaller than a certain threshold value) is met, the obtained seismic source position is the second seismic source position, and the seismic source space-time parameters such as the seismic wave propagation path, the seismic occurrence time and the like are determined.
By matching comparison and seismic source position adjustment, the propagation characteristic and reflection characteristic of seismic waves in a complex geological structure are considered, so that more accurate seismic source space-time parameters are obtained, the accuracy of seismic source positioning is further improved, and more accurate initial conditions are provided for subsequent inversion iteration.
Further, step S434 of the embodiment of the present application includes:
And step S434-1, outputting a theoretical delay time array by carrying out seismic wave delay analysis on the theoretical time sequence array.
And step S434-2, performing matching comparison on the seismic wave delay time array, the seismic reflection wave characteristic array, the theoretical reflection wave characteristic array and the theoretical delay time array based on Euclidean distance, and outputting a first position difference degree.
And step S434-3, performing iterative adjustment on the first seismic source position according to the first position difference degree until the second seismic source position with the position difference degree smaller than the preset value is obtained.
And step S434-4, carrying out related theoretical data call according to the second seismic source position to obtain theoretical occurrence time and the seismic wave propagation path.
And step S434-5, performing real time correction on the theoretical occurrence time to obtain the earthquake occurrence time.
Specifically, the theoretical delay time array is obtained by performing seismic wave delay analysis on a theoretical time series array, and includes an array of delay times of seismic waves at each detection point in a theoretical situation. And analyzing the delay condition of the seismic wave in the process of propagating to each detection point according to the seismic wave propagation theory and the geological parameters and other information in the model aiming at each time data in the theoretical time sequence array. For example, the theoretical delay time of the seismic wave at each detection point relative to a certain reference time is calculated by considering factors such as the propagation speed difference of the seismic wave in different stratum and the length of the propagation path, and the calculation results are arranged according to the detection point sequence to form a theoretical delay time array.
The first position difference degree is a numerical value reflecting the degree of difference between an actual data array (seismic wave delay time array, seismic reflection wave characteristic array) and a theoretical data array (theoretical reflection wave characteristic array, theoretical delay time array) obtained by Euclidean distance calculation. The seismic wave delay time array, the seismic reflection wave characteristic array, the theoretical reflection wave characteristic array, and the theoretical delay time array are regarded as vectors in a multidimensional space (the data corresponding to each detection point is regarded as one dimension of the vectors). And respectively calculating the distance between the actual data array and the theoretical data array according to the Euclidean distance. The distances are combined to obtain a first degree of positional discrepancy. The first position difference degree quantifies the difference between actual data and theoretical data, provides a clear adjustment basis for iterative adjustment of the position of the seismic source, and can judge the deviation degree of the current seismic source position hypothesis and the actual situation.
And determining the adjustment direction and amplitude of the position of the seismic source according to the first position difference degree. If the first position difference degree is larger, the focus position is supposed to deviate from the actual situation greatly, and the focus position needs to be adjusted greatly, and if the first position difference degree is smaller, the focus position is adjusted slightly. After the adjustment, a new first position difference degree is calculated again. The process is repeated until the position difference degree is smaller than a preset value, and the obtained focus position is the second focus position. The preset value is a preset value and is used for judging whether the position adjustment of the seismic source reaches enough precision. When the position difference is less than a preset value, the source position is considered to be sufficiently accurate. Through iterative adjustment, the gap between the source position assumption and the actual situation is gradually reduced, the second source position meeting the precision requirement is finally obtained, and the accuracy of source positioning is improved.
In the seismic wave propagation model, after the second seismic source position is determined, the theoretical occurrence time (namely, the time when the earthquake occurs theoretically) and the seismic wave propagation path (the theoretical path of the seismic wave propagating from the seismic source to each detection point) corresponding to the seismic source position are searched according to the physical rule of the seismic wave propagation and the data structure in the model.
The theoretical occurrence time is adjusted by combining the time information of the actually detected seismic waves reaching each detection point and other practical factors (such as the time error of detection equipment, and the like), so that the accurate seismic occurrence time is obtained, the seismic source space-time parameters are more complete and accurate, and the seismic event analysis is facilitated. For example, if the actual detected seismic wave arrives at a certain detection point a certain amount later than the theoretical arrival time at that detection point, then correction of the theoretical occurrence time is required based on this time difference.
In summary, the method for positioning the seismic source based on the three-dimensional seismic reflection data provided by the embodiment of the application has the following beneficial effects:
According to the embodiment of the application, three-dimensional geological reflection data are collected as a basis, the initial positioning of a seismic source is firstly carried out, then a reflected wave time sequence array is extracted, then various data are associated and analyzed by taking the initial positioning as a starting point to obtain the time-space parameters of the seismic source, a three-dimensional seismic wave velocity model is built and is used as iteration constraint to carry out inversion iteration, and finally the target seismic source position is output. The whole scheme fully utilizes the three-dimensional geological reflection data and the reflected wave time sequence array, combines the pre-constructed three-dimensional seismic wave velocity model, realizes high-precision positioning of the position of the seismic source, can effectively improve the precision and reliability of the positioning of the seismic source, simultaneously enhances the adaptability to complex geological structures, and provides a more advanced and effective technical means for the positioning of the seismic source in the fields of geological exploration, coal resource detection and the like.
In a second embodiment, as shown in fig. 2, based on the same inventive concept as the previous embodiment, an embodiment of the present application provides a source positioning system based on three-dimensional seismic reflection data, the system includes:
the geological reflection data acquisition module 10 is configured to acquire three-dimensional geological reflection data by arranging a detection point array in a target research area, where the three-dimensional geological reflection data includes a plurality of seismic trace data of a plurality of detection points in the detection point array.
The source initial positioning module 20 is configured to perform source initial positioning according to the three-dimensional geological reflection data, so as to obtain a first source position.
A time series array extraction module 30, configured to extract a reflected wave time series array mapped to the detection point array from the three-dimensional geological reflection data.
The source space-time parameter obtaining module 40 is configured to perform a correlation analysis on the three-dimensional geological reflection data and the reflected wave time sequence array by using the first source position as an optimization starting point, so as to obtain a source space-time parameter.
The model construction module 50 is used for pre-constructing a three-dimensional seismic wave velocity model.
The target source position determining module 60 is configured to perform inversion iteration using the source space-time parameter as an initial condition and the three-dimensional seismic wave velocity model as an iteration constraint until a preset convergence condition is reached, and output a target source position.
Further, the source initial positioning module 20 according to the embodiment of the present application is further configured to perform the following steps:
The method comprises the steps of carrying out geological data coverage analysis on a target research area, carrying out data calling according to an analysis result to obtain geological priori information, constructing a seismic wave propagation model according to the geological priori information, loading three-dimensional geological reflection data to the seismic wave propagation model, and carrying out seismic source initial positioning through simulation matching to obtain a first seismic source position.
Further, the source spatiotemporal parameter acquisition module 40 of the embodiment of the present application is further configured to perform the following steps:
The method comprises the steps of carrying out earthquake wave delay analysis on the reflected wave time sequence array, outputting an earthquake wave delay time array, carrying out waveform feature recognition on the three-dimensional earthquake reflection data to obtain an earthquake reflection wave feature array, carrying out source position iterative adjustment on the first source position in the earthquake wave propagation model by referring to the earthquake wave delay time array and the earthquake reflection wave feature array to obtain source space-time parameters, wherein the source space-time parameters comprise a second source position, an earthquake wave propagation path and earthquake occurrence time.
Further, the source initial positioning module 20 according to the embodiment of the present application is further configured to perform the following steps:
The method comprises the steps of taking a target research area as a retrieval constraint, retrieving and calling area geological data, wherein the area geological data comprises a plurality of geological parameter information of a plurality of area strata, the geological parameter information comprises medium density, longitudinal wave speed and constant wave speed, carrying out coverage integrity analysis on the target research area according to the area strata to obtain a deviation stratum interval, interactively obtaining target geological conditions of the target research area, taking the target geological conditions and the deviation stratum interval as matching conditions, matching to obtain priori geological data, and fusing the priori geological data to the geological parameter information according to the deviation stratum interval to serve as the geological priori information.
Further, the source initial positioning module 20 according to the embodiment of the present application is further configured to perform the following steps:
Extracting stratum distribution information of the target research area from the geological data of the area, constructing a stratum distribution model according to the stratum distribution information, gridding the stratum distribution model by a preset grid scale to obtain a plurality of three-dimensional grid units, mapping and scheduling geological parameter values from the geological priori information according to stratum sources of the plurality of three-dimensional grid units, and performing grid filling to complete construction of the seismic wave propagation model.
Further, the time-series array extraction module 30 according to the embodiment of the present application is further configured to perform the following steps:
The method comprises the steps of detecting, covering and analyzing a target research area, outputting a detection point array, collecting seismic wave reflection signals through a first seismic detector arranged at a first detection point to obtain first seismic channel data, wherein the first seismic channel data comprise a first reflected wave time sequence, first reflected wave position coordinates and first reflected wave amplitude, the first seismic channel data are transmitted to a data processing center through a wireless communication network, the data processing center receives the plurality of seismic channel data in the same way, and after the plurality of reflected wave time sequences are extracted from the plurality of seismic channel data, the plurality of reflected wave time sequences are structured according to the plurality of reflected wave position coordinates by the data processing center to obtain the reflected wave time sequence array.
Further, the source spatiotemporal parameter acquisition module 40 of the embodiment of the present application is further configured to perform the following steps:
After the seismic wave propagation model locates the first seismic source position, data acquisition of a seismic wave propagation simulation process is carried out to obtain theoretical reflected wave data, waveform characteristic identification is carried out on the theoretical reflected wave data to obtain a theoretical reflected wave characteristic array, a theoretical time sequence array mapped to the detection point array is extracted from the theoretical reflected wave data, and seismic source position adjustment is carried out on the first seismic source position according to a matching comparison result of the seismic wave delay time array, the seismic reflected wave characteristic array, the theoretical reflected wave characteristic array and the theoretical time sequence array until the seismic source space-time parameters are obtained through iterative adjustment.
Further, the source spatiotemporal parameter acquisition module 40 of the embodiment of the present application is further configured to perform the following steps:
The method comprises the steps of carrying out seismic wave delay analysis on a theoretical time sequence array to output a theoretical delay time array, carrying out matching comparison on the seismic wave delay time array, a seismic reflection wave characteristic array, a theoretical reflection wave characteristic array and the theoretical delay time array based on Euclidean distance to output first position difference degree, carrying out iterative adjustment on the first seismic source position according to the first position difference degree until the second seismic source position with the position difference degree smaller than a preset value is obtained, carrying out associated theoretical data call according to the second seismic source position to obtain theoretical occurrence time and a seismic wave propagation path, and carrying out actual time correction on the theoretical occurrence time to obtain the seismic occurrence time.
The foregoing detailed description of the method for locating a seismic source based on three-dimensional seismic reflection data will clearly enable those skilled in the art to know that the system for locating a seismic source based on three-dimensional seismic reflection data in this embodiment is provided with corresponding functional modules and beneficial effects for the system disclosed in the second embodiment, and relevant places refer to the description of the method section.
In a third embodiment, based on the same inventive concept as the method for positioning a seismic source based on three-dimensional seismic reflection data in the first embodiment, the present application further provides an electronic device, including at least one processor, and a memory communicatively connected to the at least one processor, wherein the memory stores instructions executable by the at least one processor, and the instructions are executed by the at least one processor, so that the at least one processor can execute the steps of the method for positioning a seismic source based on three-dimensional seismic reflection data in the first embodiment.
As shown in FIG. 3, the bus architecture is represented by a bus 300, where the bus 300 may include any number of interconnected buses and bridges, the bus 300 connecting together various circuits, including one or more processors, represented by a processor 302, and memory, represented by a memory 304. Bus 300 may also connect together various other circuits such as peripherals, voltage regulators, and power management circuits, which are well known in the art, and therefore, will not be described any further herein. Bus interface 305 provides an interface between bus 300 and receiver 301 and transmitter 303. The receiver 301 and the transmitter 303 may be the same element, i.e. a transceiver, providing a means for communicating with various other apparatus over a transmission medium. The processor 302 is responsible for managing the bus 300 and general processing, while the memory 304 may be used to store data used by the processor 302 in performing operations.
The previous description of the disclosed embodiments is provided to enable any person skilled in the art to make or use the present application. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the generic principles defined herein may be applied to other embodiments without departing from the spirit or scope of the application. Thus, the present application is not intended to be limited to the embodiments shown herein but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.