Abstract
The study of the stress-strain state of a medium in seismically quiet areas is difficult because of the absence of strong events. Under such circumstances, each earthquake, even relatively weak, is of high importance. In this case, all possible information on tectonic stresses and their dynamics, e.g., information on time, location, and magnitude of aftershocks, should be obtained from available seismic data. The earthquake near the town of Mariupol which occurred on August 7, 2016, had a body wave magnitude of 4.5–4.9 from the data of the different seismological centers. We detected 12 aftershocks that occurred within 5 days after the main shock using two seismic arrays (AKASG and BRTR) and one three-component station (KBZ) of the International Monitoring System, as well as two array stations of the Institute of Geosphere Dynamics, Russian Academy of Sciences. For six aftershocks, signals were found at three or more stations. The other aftershocks were detected from the data at two out of three nearest stations. Signal detection and association with aftershocks of the main shock, as well as estimation of magnitude and relative location of the found aftershocks, were carried out using the method of waveform cross-correlation (WFCC). The signals from the main shock that acted as the only master event (ME) for the WFCC method were used as waveform templates. To increase the signal-to-noise ratio and to determine the exact onset time of regular seismic waves from aftershocks, we used waveform templates of different length, from 10 to 180 s depending on the wave type and distance to the station, as well as band filtering in narrow frequency bands. The highest sensitivity of the detector and accuracy of the P-wave onset time estimates were reached when a waveform template included all regular waves from P to L g . Association of signals with aftershocks was based on back projection of signal arrival times to origin times using the travel time from a master event to the station, which was measured with a very low error, being equal to almost half of the digitization step length. To develop a seismic event hypothesis, the origin times at two or more stations should be spaced within a 2-s interval.
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References
Adushkin, V.V., Kitov, I.O., Konstantinovskaya, N.L., Nepeina, K.S., Nesterkina, M.A., and Sanina, I.A., Detection of ultraweak signals on the Mikhnevo small-aperture seismic array by using cross-correlation of waveforms, Dokl. Earth Sci., 2015, vol. 460, no. 2, pp. 189–191.
Adushkin, V.V., Kitov, I.O., and Sanina, I.A., Application of a three-component seismic array to improve the detection efficiency of seismic events by the matched filter method, Dokl. Earth Sci., 2016a, vol. 466, no. 1, pp. 47–50.
Adushkin, V.V., Kitov, I.O., and Sanina, I.A., Decrease in signal detection threshold by waveform cross correlation method owing to the use of a seismic array of three-component sensors, Geofiz. Issled., 2016b, vol. 17, no. 1, pp. 5–28. doi 10.21455/gr2016.1-1
Adushkin, V.V., Bobrov, D.I., Kitov, I.O., Rozhkov, M.V., and Sanina, I.A., Remote detection of aftershock activity as a new method of seismic monitoring, Dokl. Earth Sci., 2017, vol. 473, no. 1, pp. 303–307.
Baisch, S., Ceranna, L., and Harjes, H.-P., Earthquake cluster: what can we learn from wave form similarity?, Bull. Seismol. Soc. Am., 2008, vol. 98, no. 6, pp. 2806–2814.
Bobrov, D., Khukhuudei, U., Kitov, I., Sitnikov, K., and Zerbo, L., Automated recovery of the 2012 Sumatera aftershock sequence using waveform cross correlation, J. Earth Sci. Eng., 2013, vol. 3, pp. 437–460.
Bobrov D., Kitov I., and Zerbo L. Perspectives of crosscorrelation in seismic monitoring at the International Data Centre, Pure Appl. Geophys., 2014, vol. 171, nos. 3–5, pp. 439–468.
Bobrov, D.I., Kitov, I.O., Rozhkov, M.V., and Friberg, P., Towards global seismic monitoring of underground nuclear explosions using waveform cross correlation. Part I: Grand master events, Seism. Instrum., 2016a, vol. 52, no. 1, pp. 43–59.
Bobrov, D.I., Kitov, I.O., Rozhkov, M.V., and Friberg, P., Towards global seismic monitoring of underground nuclear explosions using waveform cross correlation. Part II: Synthetic master events, Seism. Instrum., 2016b, vol. 52, no. 3, pp. 207–223.
Coyne, J., Bobrov, D., Bormann, P., Duran, E., Haralabus, G., Kitov, I., Grenard, P., and Starovoit, Yu., Chapter 15: CTBTO: Goals, Networks, Data Analysis and Data Availability, in New Manual of Seismological Practice Observatory, Bormann, P., Ed., 2012, pp. 1–41. doi 10.2312/GFZ.NMSOP-2_ch15
Geller, R.J. and Mueller, C.S., Four similar earthquakes in central California, Geophys. Res. Lett., 1980, vol. 7, no. 10, pp. 821–824.
Gibbons, S.J. and Ringdal, F., The detection of low-magnitude seismic events using array-based waveform correlation, Geophys. J. Int., 2006, vol. 165, pp. 149–166.
Gibbons, S.J., Sorensen M.B., Harris D., and Ringdal F. The detection and location of low magnitude earthquakes in northern Norway using multi-channel waveform correlation at regional distances, Phys. Earth Planet. Inter., 2007, vol. 160, nos. 3–4, pp. 285–309.
Gibbons, S.J., Schweitzer, J., Ringdal, F., Kvaerna, T., Mykkeltveit, S., and Paulsen, B., Improvements to seismic monitoring of the European Arctic using three-component array processing at SPITS, Bull. Seismol. Soc. Am., 2011, vol. 101, no. 6, pp. 2737–2754.
Gibbons, S.J., Pabian, F., Näsholm, S.P., Kværna, T., and Mykkeltveit, S., Accurate relative location estimates for the North Korean nuclear tests using empirical slowness corrections, Geophys. J. Int., 2017, vol. 208, pp. 101–117. https://doi.org/10.1093/gji/ggw379.
Harris, D. and Kvaerna, T., Super-resolution with seismic arrays using empirical matched field processing, Geophys. J. Int., 2010, vol. 182, pp. 1455–1477. doi 10.1111/j.1365- 246X.2010.04684.x
Harris, D.B. and Dodge, D.A., An autonomous system for grouping events in a developing aftershock sequence, Bull. Seismol. Soc. Am., 2011, vol. 101, no. 2, pp. 763–774. doi 10.1785/0120100103
Israelsson, H., Correlation of waveforms from closely spaced regional events, Bull. Seismol. Soc. Am., 1990, vol. 80, pp. 2177–2193.
Kitov, I.O., Sanina, I.A., Nepeina K.S., and Konstantinovskaya, N.L., Using a matched-filter technique at the Mikhnevo small-aperture seismic array, Seism. Instrum., 2014, vol. 51, no. 3, pp. 191–200.
Kitov, I., Bobrov, D., Rozhkov, M., and Sanina, I., Creation of a high-resolution catalogue of mining explosions within the Russian platform using joint capabilities of seismic array Mikhnevo and the International Monitoring System, CTBT: Science and Technology 2015 Conference, Vienna, Austria, 2015, 2015, pp. 135–136.
Kitov, I.O., Volosov, S.G., Kishkina, S.B., Konstantinovskaya, N.L., Nepeina, K.S., Nesterkina, M.A., and Sanina, I.A., Detection of regional phases of seismic body waves using an array of three-component sensors, Seism. Instrum., 2016, vol. 52, no. 1, pp. 19–31.
Pustovitenko, B.G., Kul’chitskii, V.E., and Pustovitenko, A.A., New maps of seismic zoning for the territory of Ukraine. Peculiarities of the long-term seismic hazard model, Geofiz. Zh., 2006, vol. 28, no. 3, pp. 54–77.
Richards, P., Waldhauser, F., Schaff, D., and Kim, W.-Y., The applicability of modern methods of earthquake location, Pure Appl. Geophys., 2006, vol. 163, pp. 351–372.
Sanina, I., Gabsatarova, I., Chernykh, O., Riznichenko, O., Volosov, S., Nesterkina, M., and Konstantinovskaya, N., The Mikhnevo small aperture array enhances the resolution property of seismological observations on the East European Platform, J. Seismol., 2012, vol. 15, pp. 545–556.
Schaff, D.P., Bokelmann, G.H.R., Ellsworth, W.L., Zanzerkia, E., Waldhauser, F., and Beroza, G.C., Optimizing correlation techniques for improved earthquake location, Bull. Seismol. Soc. Am., 2004, vol. 94, no. 2, pp. 705–721.
Schaff, D.P. and Richards, P.G., Repeating seismic events in China, Science, 2004, vol. 303, pp. 1176–1178.
Schaff, D.P. and Richards, P.G., Improvements in magnitude precision, using the statistics of relative amplitudes measured by cross correlation, Geophys. J. Int., 2014, vol. 197, pp. 335–350. doi 10.1093/gji/ggt433
Slinkard, M., Carr, D., and Young, C., Applying waveform correlation to three aftershock sequences, Bull. Seismol. Soc. Am., 2013, vol. 103, pp. 675–693. doi 10.1785/0120120058
Van Trees, H.L., Detection, Estimation, and Modulation Theory, New York: Wiley, 1968. doi 10.1785/0120120058
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Original Russian Text © I.O. Kitov, I.A. Sanina, S.S. Sergeev, M.A. Nesterkina, N.L. Konstantinovskaya, 2017, published in Seismicheskie Pribory, 2017, Vol. 53, No. 2, pp. 58–80.
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Kitov, I.O., Sanina, I.A., Sergeev, S.S. et al. Detection, Estimation of Magnitude, and Relative Location of Weak Aftershocks Using Waveform Cross-Correlation: The Earthquake of August 7, 2016, in the Town of Mariupol. Seism. Instr. 54, 158–174 (2018). https://doi.org/10.3103/S074792391802007X
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DOI: https://doi.org/10.3103/S074792391802007X