Journal of Earth Science

, Volume 30, Issue 5, pp 1005–1009 | Cite as

Magnitude of the 23 January 2018 M7.9 Alaska Earthquake Estimated from Local Dense Seismic Records in Alaska

  • Chen Song
  • Qiang Yao
  • Dun WangEmail author
Seismology, Mathematical and Remote Sensing Geology


We apply a novel method to estimate the magnitude of the 23 January 2018 M7.9 Alaska earth-quake using seismic stations recorded at local to regional distances in Alaska, US. We determine the source duration from back-projection results derived from the Alaska stations in a relatively compact azimuth range. Then we calculate the maximum P-wave displacements recorded on a wide azimuth range at distances of 8 to 15 degrees. Combining the source duration and the maximum P-wave displacements, we obtain magnitudes of 7.86–8.03 for the 23 January 2018 earthquake in 3–5 min, very close to the Mw 7.9 determined by the USGS and GCMT. This example validates the new approach for determining magnitude of large earthquakes using local to regional stations, and its time efficiency that magnitudes of large earthquakes can be accurately estimated within in 3–5 min after origin time. Therefore, further application of this new method would help accurate estimation of size of earthquakes that occur off shore and might cause tsunami hazards.

Key words

rapid magnitude estimation back-projection real-time seismology tsunami warning geophysics 


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This work was supported by the National Natural Science Foundation of China (No. 41474050), the Fundamental Research Funds for the Central Universities, the China University of Geosciences (Wuhan) (No. CUG170602), and the National Programme on Global Change and Air-Sea Interaction (No. GASI-GEOGE-02). Comments from Alex Hulko, Chengli Liu, and two anonymous reviewers have greatly improved the manuscript. The final publication is available at Springer via

References Cited

  1. Convers, J. A., Newman, A. V., 2013. Rapid Earthquake Rupture Duration Estimates from Teleseismic Energy Rates, with Application to Real-Time Warning. Geophysical Research Letters, 40(22): 5844–5848. CrossRefGoogle Scholar
  2. Crotwell, H. P., Owens, T. J., Ritsema, J., 1999. The TauP Toolkit: Flexible Seismic Travel-Time and Ray-Path Utilities. Seismological Research Letters, 70(2): 154–160. CrossRefGoogle Scholar
  3. Ekström, G., Stein, R. S., Eaton, J. P., et al., 1992. Seismicity and Geometry of a 110-km-Long Blind Thrust Fault 1. The 1985 Kettleman Hills, California, Earthquake. Journal of Geophysical Research, 97(B4): 4843. CrossRefGoogle Scholar
  4. Fan, W. Y., Shearer, P. M., 2015. Detailed Rupture Imaging of the 25 April 2015 Nepal Earthquake Using Teleseismic Waves. Geophysical Research Letters, 42(14): 5744–5752. CrossRefGoogle Scholar
  5. Freymueller, J. T., Woodard, H., Cohen, S. C., et al., 2008. Active Deformation Processes in Alaska, Based on 15 Years of GPS Measurements. In: Freymueller, J. T., Haeussler, P. J., Wesson, R. L., et al., eds., Active Tectonics and Seismic Potential of Alaska, Geophys. Monogr. Ser., 179: 1–42. CrossRefGoogle Scholar
  6. Hanks, T. C., Kanamori, H., 1979. A Moment Magnitude Scale. Journal of Geophysical Research, 84(B5): 2348. CrossRefGoogle Scholar
  7. Hara, T., 2007a. Magnitude Determination Using Duration of High Frequency Energy Radiation and Displacement Amplitude: Application to Tsunami Earthquakes. Earth, Planets and Space, 59(6): 561–565. CrossRefGoogle Scholar
  8. Hara, T., 2007b. Measurement of the Duration of High-Frequency Energy Radiation and Its Application to Determination of the Magnitudes of Large Shallow Earthquakes. Earth, Planets and Space, 59(4): 227–231. CrossRefGoogle Scholar
  9. Hara, T., 2011. Magnitude Determination Using Duration of High Frequency Energy Radiation and Displacement Amplitude: Application to the 2011 off the Pacific Coast of Tohoku Earthquake. Earth, Planets and Space, 63(7): 525–528. CrossRefGoogle Scholar
  10. Ishii, M., Shearer, P. M., Houston, H., et al., 2005. Extent, Duration and Speed of the 2004 Sumatra-Andaman Earthquake Imaged by the Hi-Net Array. Nature, 435(7044): 933–936. CrossRefGoogle Scholar
  11. Kennett, B. L. N., Engdahl, E. R., 1991. Traveltimes for Global Earthquake Location and Phase Identification. Geophysical Journal International, 105(2): 429–465. CrossRefGoogle Scholar
  12. Krüger, F., Ohrnberger, M., 2005. Tracking the Rupture of the M w=9.3 Sumatra Earthquake over 1 150 km at Teleseismic Distance. Nature, 435(7044): 937–939. CrossRefGoogle Scholar
  13. Li, J., Liu, C. L., Zheng, Y., et al., 2017. Rupture Process of the M s 7.0 Lushan Earthquake Determined by Joint Inversion of Local Static GPS Records, Strong Motion Data, and Teleseismograms. Journal of Earth Science, 28(2): 404–410. CrossRefGoogle Scholar
  14. Naugler, F. P., Wageman, J. M., 1973. Gulf of Alaska: Magnetic Anomalies, Fracture Zones, and Plate Interaction. Geological Society of America Bulletin, 84(5): 815–821.<1575:goamaf>;2 CrossRefGoogle Scholar
  15. Pegler, G., Das, S., 1996. The 1987–1992 Gulf of Alaska Earthquakes. Tectonophysics, 257(2–4): 111–136. CrossRefGoogle Scholar
  16. Pitman, W. C. III, Hayes, D. E., 1968. Sea-Floor Spreading in the Gulf of Alaska. Journal of Geophysical Research, 73(20): 6571–6580. CrossRefGoogle Scholar
  17. Rao, G., Cheng, Y. L., Lin, A. M., et al., 2017. Relationship between Landslides and Active Normal Faulting in the Epicentral Area of the AD 1556 M~8.5 Huaxian Earthquake, SE Weihe Graben (Central China). Journal of Earth Science, 28(3): 545–554. CrossRefGoogle Scholar
  18. Satriano, C., Kiraly, E., Bernard, P., et al., 2012. The 2012 M w 8.6 Sumatra Earthquake: Evidence of Westward Sequential Seismic Ruptures Associated to the Reactivation of a N-S Ocean Fabric. Geophysical Research Letters, 39(15): L15302. CrossRefGoogle Scholar
  19. Wang, D., Kawakatsu, H., Zhuang, J., et al., 2017. Automated Determination of Magnitude and Source Length of Large Earthquakes Using Backpro-jection and P Wave Amplitudes. Geophysical Research Letters, 44(11): 5447–5456. CrossRefGoogle Scholar
  20. Wang, D., Kawakatsu, H., Mori, J., et al., 2016. Backprojection Analyses from Four Regional Arrays for Rupture over a Curved Dipping Fault: The M w7.7 24 September 2013 Pakistan Earthquake. Journal of Geophysical Research: Solid Earth, 121(3): 1948–1961. Google Scholar
  21. Wessel, P., Smith, W. H. F., 1991. Free Software Helps Map and Display Data. Eos, Transactions American Geophysical Union, 72(41): 441–446. CrossRefGoogle Scholar
  22. Yao, H., Shearer, P. M., Gerstoft, P., 2013. Compressive Sensing of Frequency-Dependent Seismic Radiation from Subduction Zone Megathrust Ruptures. Proceedings of the National Academy of Sciences, 110(12): 4512–4517. CrossRefGoogle Scholar
  23. Zhang, H., Ge, Z. X., Ding, L. Y., 2011. Three Sub-Events Composing the 2011 off the Pacific Coast of Tohoku Earthquake (M w 9.0) Inferred from Rupture Imaging by Back-Projecting Teleseismic P Waves. Earth, Planets and Space, 63(7): 595–598. CrossRefGoogle Scholar

Copyright information

© China University of Geosciences (Wuhan) and Springer-Verlag GmbH Germany, Part of Springer Nature 2019

Authors and Affiliations

  1. 1.Key Laboratory of Earthquake Geodesy, Institute of SeismologyChina Earthquake AdministrationWuhanChina
  2. 2.State Key Laboratory of Geological Processes and Mineral Resources, School of Earth SciencesChina University of GeosciencesWuhanChina

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