AUTOMATIZATION OF PROCEDURES OF INITIAL PROCESSING OF SEISMIC SIGNALS AT CALIBRATING DIRECTIONS SOURCE-STATION
Rubrics: ORIGINAL ARTICLES
Authors:
1.
Institute of Physics of the Earth, Russian Academy of Sciences, Moscow, Russia
2.
Geophysical Center RAS, Moscow, Russia
3.
Geophysical Center RAS, Moscow, Russia
4.
ZAO "Integral", Moscow, Russia
5.
Geophysical Center RAS, Moscow, Russia
Type:
Article
Pages:
from 1
to 13
Status:
Published
Received:
25.02.2010
Accepted:
25.02.2010
Published:
25.02.2010
Language:
English
Keywords:
international monitoring system, earthquake, spectra, calibration, diagnostic parameter
Abstract (English):
The Method of Dynamic Calibration MDC of stations of the International System of Seismic Monitoring ISM was developed for calibrating regions, where no underground nuclear explosions were carried out, with the purpose of providing conditions for implementation of the Comprehensive Nuclear Test-Ban Treaty CNTBT in non-calibrated regions of the globe Kedrov, 2001; Kedrov and Luke, 2001; Kedrov and Kedrov, 2003. The essence of MDC relates to adapting diagnostic parameters of identification of underground nuclear explosions UNE and earthquakes, elaborated for the region of Eurasia, taken as a Basic region Kedrov et al., 1990; Kedrov and Luke, 1999, for other researched regions RR, which differ from BR in the character of attenuation of seismic waves. The testing results of "Kalibr" research program, realizing the MDC algorithm, were obtained according to the experimental data from Central Asia and represented in the work Kedrov et al., 2008. The unique character of MDC lies in the fact that calibration of diagnostic parameters of identification of UNE and earthquakes at source-station routes was implemented by this method using only natural seismicity data within the limits of an explored region and doesn't require special underground chemical calibration explosions. In the program "Kalibr" two diagnostic parameters are used, characterizing seismic signals in temporal area Xi: ratios of maximal amplitudes Amax in wave-train of traversal S and longitudinal waves P: S/P, and also ndash; of surface LR and longitudinal wave-trains P: LR/P, and two ndash; in frequency area Gi: ratios of sums Si of spectral amplitudes of longitudinal waves in three frequency bands: S10.3-0.6 Hz, S21.3-3.0 Hz and S33.0-6.0 Hz: S1/S2 and S1/S3. Diagnostic parameters, not dependent on the influence of magnitude mb of event and epicenter distance Delta; in km, i.e. discriminants Di, characterizing only a type of event UNE and earthquake look as: DS/P = log S/P ndash; bDelta; log Delta;, DLR/P = log LR/P ndash; am mb + bDelta; log Delta;, DG1,2 = log S1 ndash; am1 mb ndash; logS2 + am2 mb ndash; bDelta; log Delta;, DG1,3 = log S1 ndash; am1 mb ndash; logS3 + am3 mb ndash; bDelta; log Delta;, where am, am1, am2, am3 and bDelta; ndash; regression coefficients, evaluated for the Basic region according to the records of UNE and earthquakes at Borovoye station BRVK, Kazakhstan separately for two zones of distances: 1 0.5ndash;1.5 ths km and 2 1.5ndash;4.0 ths km taking into account characteristic parameters of amplitudes' attenuation of seismic waves P, S and LR at a distance from an event's epicenter. In the present version of "Kalibr" program see Figure 1, initial processing of seismic signals was done in interactive regime, that significantly delayed calibration of a separate source ndash; station route. Figure 1. Scheme of algorithm of seismic data processing for dynamic calibration of ISM stations and identification of phenomena in nuclear tests-free regions. The purpose of the present work was the development of algorithms and "Spektr" and "Signal" research programs, allowing to automate the process of measuring signals' seismic parameters in large data sampling, used in "Kalibr" program thus settling down the above-mentioned problem. Quality evaluation of seismic signals' parameters, obtained automatically by "Spektr" and "Signal" research programs, was carried out on the basis of comparing with the results of data processing in interactive regime using "MSEISMO" program system Kedrov et al., 1989 and "Seismologist's workplace" "SWP" programs, which were at the authors' disposal. Testing of MDC using the developed algorithms and programs of initial processing of signals was carried out according to the records of earthquakes, registered at Makanchi station MKAR in Kazakhstan from the area of the Lobnor training ground in China and at Pandale station PDAR in the US from the neighboring area to Nevada training ground. References Kedrov O. K. 2001, Method of Seismological Calibration of the International Monitoring System Using Regional Discriminants, Doklady RAN, 380, 390ndash;395. Kedrov O. K., E. I. Luke et al. 2001, Study of Influence of Distribution of Seismic Signals on Efficiency of Identification of Underground Nuclear Explosions and Earthquakes at Regional Distances, Fizika Zemli, No. 7, 32ndash;57. Kedrov O. K., E. O. Kedrov 2003, Identification of Seismic Phenomena at "Talgar" station Taking into Account Source-Station Route, Fizika Zemli, No. 12, 14ndash;22. Kedrov O. K., V. A. An, V. A. Laushkin et al. 1990, Methods of Underground Nuclear Explosions' Monitoring by Seismic Data at Epicenter Distances over 500 kilometers, Fizika Zemli, No. 12, 31ndash;46. Kedrov O. K., E. I. Luke 1999, Recognition of Nuclear Explosions and Earthquakes in Eurasia by Seismic Data at Regional Distances, Fizika Zemli, No. 9, 52ndash;75. Kedrov O. K., E. O. Kedrov, N. A. Sergeeva et al. 2008, Application of Dynamic Calibration Method for ISM Stations in Central Asia by Natural Seismicity Data, Fizika Zemli, No. 5, 16ndash;33. Kedrov O. K., A. I. Nemytov et al. 1989, Method and Program Realization of Automatic Detection and Localization of Seismic Phenomena at Three-Component Station in Real-time Regime, Doklady AN USSR, 3071, 67ndash;73.
The Method of Dynamic Calibration MDC of stations of the International System of Seismic Monitoring ISM was developed for calibrating regions, where no underground nuclear explosions were carried out, with the purpose of providing conditions for implementation of the Comprehensive Nuclear Test-Ban Treaty CNTBT in non-calibrated regions of the globe Kedrov, 2001; Kedrov and Luke, 2001; Kedrov and Kedrov, 2003. The essence of MDC relates to adapting diagnostic parameters of identification of underground nuclear explosions UNE and earthquakes, elaborated for the region of Eurasia, taken as a Basic region Kedrov et al., 1990; Kedrov and Luke, 1999, for other researched regions RR, which differ from BR in the character of attenuation of seismic waves. The testing results of "Kalibr" research program, realizing the MDC algorithm, were obtained according to the experimental data from Central Asia and represented in the work Kedrov et al., 2008. The unique character of MDC lies in the fact that calibration of diagnostic parameters of identification of UNE and earthquakes at source-station routes was implemented by this method using only natural seismicity data within the limits of an explored region and doesn't require special underground chemical calibration explosions. In the program "Kalibr" two diagnostic parameters are used, characterizing seismic signals in temporal area Xi: ratios of maximal amplitudes Amax in wave-train of traversal S and longitudinal waves P: S/P, and also ndash; of surface LR and longitudinal wave-trains P: LR/P, and two ndash; in frequency area Gi: ratios of sums Si of spectral amplitudes of longitudinal waves in three frequency bands: S10.3-0.6 Hz, S21.3-3.0 Hz and S33.0-6.0 Hz: S1/S2 and S1/S3. Diagnostic parameters, not dependent on the influence of magnitude mb of event and epicenter distance Delta; in km, i.e. discriminants Di, characterizing only a type of event UNE and earthquake look as: DS/P = log S/P ndash; bDelta; log Delta;, DLR/P = log LR/P ndash; am mb + bDelta; log Delta;, DG1,2 = log S1 ndash; am1 mb ndash; logS2 + am2 mb ndash; bDelta; log Delta;, DG1,3 = log S1 ndash; am1 mb ndash; logS3 + am3 mb ndash; bDelta; log Delta;, where am, am1, am2, am3 and bDelta; ndash; regression coefficients, evaluated for the Basic region according to the records of UNE and earthquakes at Borovoye station BRVK, Kazakhstan separately for two zones of distances: 1 0.5ndash;1.5 ths km and 2 1.5ndash;4.0 ths km taking into account characteristic parameters of amplitudes' attenuation of seismic waves P, S and LR at a distance from an event's epicenter. In the present version of "Kalibr" program see Figure 1, initial processing of seismic signals was done in interactive regime, that significantly delayed calibration of a separate source ndash; station route. Figure 1. Scheme of algorithm of seismic data processing for dynamic calibration of ISM stations and identification of phenomena in nuclear tests-free regions. The purpose of the present work was the development of algorithms and "Spektr" and "Signal" research programs, allowing to automate the process of measuring signals' seismic parameters in large data sampling, used in "Kalibr" program thus settling down the above-mentioned problem. Quality evaluation of seismic signals' parameters, obtained automatically by "Spektr" and "Signal" research programs, was carried out on the basis of comparing with the results of data processing in interactive regime using "MSEISMO" program system Kedrov et al., 1989 and "Seismologist's workplace" "SWP" programs, which were at the authors' disposal. Testing of MDC using the developed algorithms and programs of initial processing of signals was carried out according to the records of earthquakes, registered at Makanchi station MKAR in Kazakhstan from the area of the Lobnor training ground in China and at Pandale station PDAR in the US from the neighboring area to Nevada training ground. References Kedrov O. K. 2001, Method of Seismological Calibration of the International Monitoring System Using Regional Discriminants, Doklady RAN, 380, 390ndash;395. Kedrov O. K., E. I. Luke et al. 2001, Study of Influence of Distribution of Seismic Signals on Efficiency of Identification of Underground Nuclear Explosions and Earthquakes at Regional Distances, Fizika Zemli, No. 7, 32ndash;57. Kedrov O. K., E. O. Kedrov 2003, Identification of Seismic Phenomena at "Talgar" station Taking into Account Source-Station Route, Fizika Zemli, No. 12, 14ndash;22. Kedrov O. K., V. A. An, V. A. Laushkin et al. 1990, Methods of Underground Nuclear Explosions' Monitoring by Seismic Data at Epicenter Distances over 500 kilometers, Fizika Zemli, No. 12, 31ndash;46. Kedrov O. K., E. I. Luke 1999, Recognition of Nuclear Explosions and Earthquakes in Eurasia by Seismic Data at Regional Distances, Fizika Zemli, No. 9, 52ndash;75. Kedrov O. K., E. O. Kedrov, N. A. Sergeeva et al. 2008, Application of Dynamic Calibration Method for ISM Stations in Central Asia by Natural Seismicity Data, Fizika Zemli, No. 5, 16ndash;33. Kedrov O. K., A. I. Nemytov et al. 1989, Method and Program Realization of Automatic Detection and Localization of Seismic Phenomena at Three-Component Station in Real-time Regime, Doklady AN USSR, 3071, 67ndash;73.
Keywords:
international monitoring system, earthquake, spectra, calibration, diagnostic parameter
international monitoring system, earthquake, spectra, calibration, diagnostic parameter
1. Kedrov, Doklady RAN, v. 380, 2001.
2. Kedrov, Fizika Zemli, v. 12, 2003.
3. Kedrov, Fizika Zemli, v. 9, 1999.
4. Kedrov, Fizika Zemli, v. 7, 2001.
5. Kedrov, Doklady AN USSR, v. 3071, 1989.
6. Kedrov, Fizika Zemli, v. 12, 1990.
7. Kedrov, Fizika Zemli, v. 5, 2008.
