CN111965695B - Small fault fall detection method based on reflection groove wave - Google Patents
Small fault fall detection method based on reflection groove wave Download PDFInfo
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- CN111965695B CN111965695B CN202010827051.7A CN202010827051A CN111965695B CN 111965695 B CN111965695 B CN 111965695B CN 202010827051 A CN202010827051 A CN 202010827051A CN 111965695 B CN111965695 B CN 111965695B
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- 238000001514 detection method Methods 0.000 title claims abstract description 19
- 239000003245 coal Substances 0.000 claims abstract description 36
- 238000001914 filtration Methods 0.000 claims abstract description 9
- 238000005520 cutting process Methods 0.000 claims abstract description 8
- 238000005065 mining Methods 0.000 claims abstract description 5
- 239000000839 emulsion Substances 0.000 claims abstract description 4
- 239000002360 explosive Substances 0.000 claims abstract description 4
- 238000001228 spectrum Methods 0.000 claims description 15
- 238000000034 method Methods 0.000 claims description 8
- 238000000605 extraction Methods 0.000 claims description 5
- 238000012545 processing Methods 0.000 claims description 4
- 238000009826 distribution Methods 0.000 claims description 3
- 238000007619 statistical method Methods 0.000 claims description 2
- 238000004458 analytical method Methods 0.000 abstract description 7
- 238000010586 diagram Methods 0.000 description 5
- 239000011435 rock Substances 0.000 description 4
- 238000011160 research Methods 0.000 description 3
- 238000012986 modification Methods 0.000 description 2
- 230000004048 modification Effects 0.000 description 2
- 230000002457 bidirectional effect Effects 0.000 description 1
- 230000009172 bursting Effects 0.000 description 1
- 239000002131 composite material Substances 0.000 description 1
- 238000007405 data analysis Methods 0.000 description 1
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- 230000000694 effects Effects 0.000 description 1
- 230000005284 excitation Effects 0.000 description 1
- 238000004519 manufacturing process Methods 0.000 description 1
- 238000013507 mapping Methods 0.000 description 1
- 238000010183 spectrum analysis Methods 0.000 description 1
- 238000012360 testing method Methods 0.000 description 1
- 230000005641 tunneling Effects 0.000 description 1
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 1
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01V—GEOPHYSICS; GRAVITATIONAL MEASUREMENTS; DETECTING MASSES OR OBJECTS; TAGS
- G01V1/00—Seismology; Seismic or acoustic prospecting or detecting
- G01V1/28—Processing seismic data, e.g. for interpretation or for event detection
- G01V1/282—Application of seismic models, synthetic seismograms
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01V—GEOPHYSICS; GRAVITATIONAL MEASUREMENTS; DETECTING MASSES OR OBJECTS; TAGS
- G01V1/00—Seismology; Seismic or acoustic prospecting or detecting
- G01V1/28—Processing seismic data, e.g. for interpretation or for event detection
- G01V1/30—Analysis
- G01V1/306—Analysis for determining physical properties of the subsurface, e.g. impedance, porosity or attenuation profiles
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01V—GEOPHYSICS; GRAVITATIONAL MEASUREMENTS; DETECTING MASSES OR OBJECTS; TAGS
- G01V2210/00—Details of seismic processing or analysis
- G01V2210/60—Analysis
- G01V2210/64—Geostructures, e.g. in 3D data cubes
- G01V2210/642—Faults
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- Y04S10/00—Systems supporting electrical power generation, transmission or distribution
- Y04S10/50—Systems or methods supporting the power network operation or management, involving a certain degree of interaction with the load-side end user applications
- Y04S10/52—Outage or fault management, e.g. fault detection or location
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Abstract
The invention discloses a small fault fall detection method based on reflection groove waves, wherein p transverse wave detectors are arranged at equal intervals in the middle height of a coal seam in a detection fault area in a single roadway of a coal roadway, and mining emulsion explosive is adopted to excite once at a detection starting point to generate a seismic source; analyzing the seismic source record, determining the position of the reflected groove wave, and performing direct wave cutting; extracting main amplitude of the cut direct wave source record to obtain X-component reflection groove wave amplitude; filtering the X-component reflection groove wave to obtain filtered X-component reflection groove wave energy; obtaining the energy change rule of the faults by contrast analysis, and analyzing the fault positions according to the data; extracting the wavelet type of the reflected slot wave and determining the frequency of the reflected slot wave; and establishing three-dimensional space models of different fall faults according to the obtained information to obtain the energy change rule of the reflection groove waves of the different fall faults, thereby achieving the purpose of detecting the fall of the small fault.
Description
Technical Field
The invention relates to the technical field of seismic data analysis, in particular to a small fault fall detection method based on reflection groove waves.
Background
Large coal mining machines are commonly used in coal mine production, large stopes are more and more, and the problem of stope safety of working faces is a focus of increasing attention in coal mine development.
The slot wave exploration can play a certain role in exploration of harmful geology such as faults, collapse columns and the like, for example, the trend of a coal bed is identified, but the exploration and research on the aspect of estimating the fault fall are still needed. The slot wave exploration effectively surveys various geological structures in the coal seam by utilizing the guidance effect of the coal seam on the seismic waves. The fault is a hidden potential safety hazard in the coal roadway tunneling process, and gas outburst or water bursting accidents can be caused, so that the search of a feasible fault analysis method is necessary. At present, the research on faults in coal beds in China is quite plentiful, but the detection, analysis and research on fault throw, especially small and medium fault throw, are quite few.
Disclosure of Invention
Aiming at the problems, the invention provides a small fault throw detection method based on a reflection groove wave, which is used for detecting the small fault throw in a coal mine.
A small fault fall detection method based on reflection groove waves comprises the following steps:
step 4, filtering the X component reflection groove wave to obtain the energy of the X component reflection groove wave after filtering;
step 6, extracting the wavelet type of the reflected slot wave and determining the frequency of the reflected slot wave;
and 7, establishing three-dimensional space models of faults with different fall according to the information obtained in the step 5 and the step 6 to obtain the energy change rule of the reflection groove waves of the faults with different fall, thereby achieving the purpose of detecting the fall of the small faults.
Further, the step 1 specifically includes the following steps:
step A1, arranging p transverse wave detectors at equal intervals in the middle height of a coal seam of a fault detection area in a single coal roadway;
step A2, exciting once at a detection starting point by adopting a mining emulsion explosive to generate a seismic source;
a3, establishing a three-dimensional rectangular space coordinate system along the coal roadway, wherein the X direction points to the region to be detected, the Y direction is perpendicular to the coal wall, and the Z direction is perpendicular to the coal seam roof;
and A4, determining coordinate positions of the seismic source and the p transverse wave detectors in three-dimensional rectangular space coordinates.
Further, the step 3 is implemented by a main energy function E (t 0 ,f 0 ,x)＝E max (t 0 ,f 0 X) obtaining, X-component reflection groove wave amplitude
/>
Further, the step 4 includes the following steps:
step B1, obtaining reflection groove wave spectrum information;
step B2, intercepting the frequency width of a higher energy frequency band;
step B3, band-pass filtering with the frequency bandwidth of 50Hz is carried out on the intercepted reflection groove wave;
step B4, processing the offset distance to obtain a reflected groove wave incident angle, wherein the incident angle is defined as an abscissa;
and step B5, maximum amplitude extraction is carried out on the filtered reflection groove wave data.
Further, the step 6 includes the following steps:
step C1, obtaining the real part S (omega) = |S (omega) |e of the reliable wavelet amplitude logarithmic spectrum by using a multi-channel statistical method j πω Determining a wavelet amplitude log spectrum
Step C2, calculating wavelet phase spectrum from wavelet amplitude logarithmic spectrum
Available phase Spectrum->
Wherein->
Is->
Odd part of->
Is->
Is a pair of parts;
step C3, extracting wavelets
And C4, determining the size of the using frequency according to the frequency energy distribution.
According to the invention, related information is acquired by establishing a three-dimensional coal roadway single roadway observation system, and three-dimensional space models of faults with different fall angles are established according to the acquired information, so that the energy change rule of the reflection groove waves of the faults with different fall angles is obtained, and the purpose of detecting the fall angles of the small faults is achieved.
Drawings
FIG. 1 is a schematic diagram of a source and detector arrangement;
FIG. 2 is a schematic diagram of a reflected notch wave;
FIG. 3 is a graph of simulated data for a notch;
FIG. 4 is a graph of simulated data after cutting;
FIG. 5 is a reflection tank wave wavelet morphology diagram;
FIG. 6 is a schematic diagram of a reflected notch wave;
FIG. 7 is a tomographic three-dimensional space model;
FIG. 8 is a graph of energy extracted from different drop models.
Detailed Description
The invention will be described in further detail with reference to the drawings and the detailed description. The embodiments of the invention have been presented for purposes of illustration and description, and are not intended to be exhaustive or limited to the invention in the form disclosed. Many modifications and variations will be apparent to those of ordinary skill in the art. The embodiments were chosen and described in order to best explain the principles of the invention and the practical application, and to enable others of ordinary skill in the art to understand the invention for various embodiments with various modifications as are suited to the particular use contemplated.
Example 1
A small fault fall detection method based on reflection groove waves comprises the following steps:
1. a three-dimensional coal roadway single tunnel observation system is established in a coal roadway single tunnel detection fault area, and the observation system mainly comprises a seismic source, a plurality of detectors distributed at equal intervals and a three-dimensional rectangular space coordinate system for providing position coordinates for the seismic source and the detectors, as shown in figure 1.
The three-dimensional rectangular space coordinate system is established along the coal roadway, the X direction points to the region to be detected, the Y direction is perpendicular to the coal wall, and the Z direction is perpendicular to the coal seam roof. The seismic source is produced by excitation of mining emulsion explosive at a detection starting point. The three-dimensional observation system observation object comprises surrounding rock and a coal bed, the speed of the surrounding rock and the bulk wave speed of the coal bed are completely set by referring to the coal bed and rock speed parameters of the real test, and the sizes of the coal bed and the surrounding rock are consistent.
2. And analyzing the seismic source record, determining the position of the reflected groove wave, and performing direct wave cutting processing as shown in figure 2. The cutting of the direct wave refers to complete cutting of the direct wave including the direct groove wave, and only reflected groove wave data is obtained. Fig. 3 and 4 are graphs of simulated data before and after the cutting, respectively.
3. And extracting the main amplitude of the cut direct wave source record to obtain the X-component reflection groove wave amplitude. The amplitude extraction is to convert the time-frequency-space domain seismic record into a time-frequency domain, and quantitatively extract main characteristic parameters which can represent the overall characteristics of the waveform of the reflected wave of each geological horizon in the time-frequency domain. As is known from signal analysis theory, the resolution of the composite signal is highest in the time-frequency domain, so that the main parameters of the signal characteristics extracted in the time-frequency domain are higher than the accuracy extracted in the time domain. The energy extraction is to extract the energy of the reflected groove wave according to the number of channels, and the maximum value of each channel is extracted during the analysis of the energy of the reflected groove wave.
Energy function E (t, f, x) = |epsilon (t, f, x) |in the time-frequency-space domain
Satisfy the following requirements
The main energy function E (t) 0 ,f 0 ,x)＝E max (t 0 ,f 0 X), where f 0 And t 0 The main frequency and group delay of the seismic signals, t 0 Which may be referred to as the delay time of the main energy of the seismic signal. Pair E 0 The square of the opening can obtain the value of the main amplitude of the reflected wave
4. Filtering the X-component reflection groove wave to obtain the energy of the filtered X-component reflection groove wave, and specifically comprising the following steps:
the method comprises the steps of obtaining reflection groove wave spectrum information;
intercepting the bandwidth of a higher energy frequency band;
thirdly, band-pass filtering with the frequency bandwidth of 50Hz is carried out on the intercepted reflection groove wave;
fourthly, processing the offset distance to obtain a reflection groove wave incident angle, and defining the angle as an abscissa;
and fifthly, carrying out maximum amplitude extraction on the filtered reflection groove wave data.
5. Obtaining the energy change rule of faults by contrast analysis, converting the number of channels of an observation system into the incident angle of reflected waves, mapping the incident angle of reflected waves for analysis, determining the energy information of faults with different fall, and analyzing the fault positions;
6. extracting wavelet type of the reflected slot wave, and determining the frequency size of the reflected slot wave, wherein the method specifically comprises the following steps:
the method comprises obtaining the real part S (omega) = |S (omega) |e of reliable wavelet amplitude logarithmic spectrum by using multi-channel statistics jπω Determining a wavelet amplitude log spectrum
Obtaining wavelet phase spectrum from wavelet amplitude logarithmic spectrum
Available phase Spectrum->
Wherein->
Is->
Odd part of->
Is->
Is a pair of parts; />
Extracting wavelets
And determining the size of the using frequency according to the frequency energy distribution.
The three-dimensional simulated wavelet form (see fig. 5) is a wavelet form extracted from an actual signal, the frequency of the wavelet is the main frequency with the highest maximum energy obtained after the spectral analysis of an actual slot wave, and the wavelet type adopts a bidirectional parallel seismic source capable of generating a love slot wave. The model selects wavelet type as single wavelet with frequency of 120Hz, the model boundary adopts multilayer pml boundary, no interference of boundary reflection is ensured, the finite difference adopts multi-gradient difference, the differential grid is thinned in the coal seam, and the model boundary adopts large grid difference, thus saving the model operation time.
7. The schematic diagram of the reflected groove wave is shown in fig. 6, a three-dimensional space model of different fall faults is built according to the information obtained in the step 5 and the step 6, the three-dimensional space model is shown in fig. 7, and the energy change rule of the reflected groove wave of the different fall faults is obtained, and the three-dimensional space model is shown in fig. 8. It can be seen from fig. 8 that the amplitude and the incident angle have a strong correlation, and the incident angle and the fault throw have a strong correlation, so that the energy change rule of the fault reflection slot waves with different throws achieves the purpose of detecting small fault throws.
It will be apparent that the described embodiments are only some, but not all, embodiments of the invention. All other embodiments, which can be made by those skilled in the art and which are included in the embodiments of the present invention without the inventive step, are intended to be within the scope of the present invention.
Claims (5)
1. The small fault fall detection method based on the reflection groove wave is characterized by comprising the following steps of:
step 1, a three-dimensional coal roadway single tunnel observation system is established in a coal roadway single tunnel detection fault area, and the observation system mainly comprises a seismic source, a plurality of detectors distributed at equal intervals and a three-dimensional rectangular space coordinate system for providing position coordinates for the seismic source and the detectors;
step 2, analyzing the seismic source record, determining the position of the reflected groove wave, and performing direct wave cutting;
step 3, extracting main amplitude of the cut direct wave source record to obtain X-component reflection groove wave amplitude;
step 4, filtering the X component reflection groove wave to obtain the energy of the X component reflection groove wave after filtering;
step 5, comparing and analyzing to obtain the energy change rule of the fault, and analyzing the fault position according to the data;
step 6, extracting the wavelet type of the reflected slot wave and determining the frequency of the reflected slot wave;
and 7, establishing three-dimensional space models of faults with different fall according to the information obtained in the step 5 and the step 6 to obtain the energy change rule of the reflection groove waves of the faults with different fall, thereby achieving the purpose of detecting the fall of the small faults.
2. The method for detecting the small fault throw based on the reflected groove wave according to claim 1, wherein the step 1 specifically comprises the following steps:
step A1, arranging p transverse wave detectors at equal intervals in the middle height of a coal seam of a fault detection area in a single coal roadway;
step A2, exciting once at a detection starting point by adopting a mining emulsion explosive to generate a seismic source;
a3, establishing a three-dimensional rectangular space coordinate system along the coal roadway, wherein the X direction points to the region to be detected, the Y direction is perpendicular to the coal wall, and the Z direction is perpendicular to the coal seam roof;
and A4, determining coordinate positions of the seismic source and the p transverse wave detectors in three-dimensional rectangular space coordinates.
3. The method for detecting small fault throw based on reflected slot waves according to claim 1 or 2, wherein said step 3 is performed by a main energy function E (t 0 ,f 0 ,x)＝E max (t 0 ,f 0 X) obtaining, X-component reflection groove wave amplitude
Wherein f 0 And t 0 The main frequency and group delay of the seismic signal, respectively.
4. The method for detecting a small fault throw based on a reflected groove wave according to claim 1 or 2, wherein the step 4 comprises the steps of:
step B1, obtaining reflection groove wave spectrum information;
step B2, intercepting the frequency width of a higher energy frequency band;
step B3, band-pass filtering with the frequency bandwidth of 50Hz is carried out on the intercepted reflection groove wave;
step B4, processing the offset distance to obtain a reflected groove wave incident angle, wherein the incident angle is defined as an abscissa;
and step B5, maximum amplitude extraction is carried out on the filtered reflection groove wave data.
5. The method for detecting small fault throw based on reflection slot waves according to claim 1 or 2, wherein the step 6 comprises the steps of:
step C1, obtaining the real part S (omega) = |S (omega) |e of the reliable wavelet amplitude logarithmic spectrum by using a multi-channel statistical method jπω Determining a wavelet amplitude log spectrum
Step C2, calculating wavelet phase spectrum from wavelet amplitude logarithmic spectrum
Available phase Spectrum->
Wherein->
Is->
Odd part of->
Is->
Is a pair of parts;
step C3, extracting wavelets
And C4, determining the size of the using frequency according to the frequency energy distribution.
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