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The 11 April 2012 east Indian Ocean earthquake triggered large aftershocks worldwide


Large earthquakes trigger very small earthquakes globally during passage of the seismic waves and during the following several hours to days1,2,3,4,5,6,7,8,9,10, but so far remote aftershocks of moment magnitude M ≥ 5.5 have not been identified11, with the lone exception of an M = 6.9 quake remotely triggered by the surface waves from an M = 6.6 quake 4,800 kilometres away12. The 2012 east Indian Ocean earthquake that had a moment magnitude of 8.6 is the largest strike-slip event ever recorded. Here we show that the rate of occurrence of remote M ≥ 5.5 earthquakes (>1,500 kilometres from the epicentre) increased nearly fivefold for six days after the 2012 event, and extended in magnitude to M ≤ 7. These global aftershocks were located along the four lobes of Love-wave radiation; all struck where the dynamic shear strain is calculated to exceed 10−7 for at least 100 seconds during dynamic-wave passage. The other M ≥ 8.5 mainshocks during the past decade are thrusts; after these events, the global rate of occurrence of remote M ≥ 5.5 events increased by about one-third the rate following the 2012 shock and lasted for only two days, a weaker but possibly real increase. We suggest that the unprecedented delayed triggering power of the 2012 earthquake may have arisen because of its strike-slip source geometry or because the event struck at a time of an unusually low global earthquake rate, perhaps increasing the number of nucleation sites that were very close to failure.

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Figure 1: The 2012 M = 8.6 mainshock and M = 8.2 aftershock fault ruptures and maps of strain duration τ strain at a threshold value of 0.1 microstrain.
Figure 2: Global rates of shallow (depth, ≤100 km) M  ≥ 5.5 earthquakes during the 10 d preceding and following a mainshock.
Figure 3: Cumulative number of global M  ≥ 4.5 events of depth ≤100 km during the 6 d before and after the 2012 event.
Figure 4: Global seismicity rates during the 7.3 yr between the 2004 Sumatra earthquake and the 2012 east Indian Ocean earthquake.


  1. Hill, D. P. et al. Seismicity in the western United States remotely triggered by the M7.4 Landers, California, earthquake of June 28, 1992. Science 260, 1617–1623 (1993)

    Article  CAS  ADS  Google Scholar 

  2. Kilb, D., Gomberg, J. & Bodin, P. Triggering of earthquake aftershocks by dynamic stresses. Nature 408, 570–574 (2000)

    Article  CAS  ADS  Google Scholar 

  3. Gomberg, J., Reasenberg, P., Bodin, P. & Harris, R. Earthquake triggering by transient seismic waves following the Landers and Hector Mine, California earthquakes. Nature 411, 462–466 (2001)

    Article  CAS  ADS  Google Scholar 

  4. Prejean, K. et al. Remotely triggered seismicity on the United States west coast following the M w 7.9 Denali Fault earthquake. Bull. Seismol. Soc. Am. 94, S348–S359 (2004)

    Article  Google Scholar 

  5. Gomberg, J., Bodin, P., Larson, K. & Dragert, H. Earthquake nucleation by transient deformations caused by the M = 7.9 Denali, Alaska, earthquake. Nature 427, 621–624 (2004)

    Article  CAS  ADS  Google Scholar 

  6. Husen, S., Taylor, R., Smith, R. B. & Healser, H. Changes in geyser eruption behavior and remotely triggered seismicity in Yellowstone National Park produced by the 2002 M7.9 Denali Fault earthquake, Alaska. Geology 32, 537–540 (2004)

    Article  ADS  Google Scholar 

  7. Pankow, K. L., Arabasz, W. J., Pechman, J. C. & Nava, S. J. Triggered seismicity in Utah from the November 3, 2002, Denali Fault earthquake. Bull. Seismol. Soc. Am. 94, S332–S347 (2004)

    Article  Google Scholar 

  8. Brodsky, E. E. & Prejean, S. G. New constraints on mechanisms of remotely triggered seismicity at Long Valley Caldera. J. Geophys. Res. 110, B04302 (2005)

    Article  ADS  Google Scholar 

  9. Velasco, A. A., Hernandez, S., Parsons, T. & Pankow, K. Global ubiquity of dynamic earthquake triggering. Nature Geosci. 1, 375–379 (2008)

    Article  CAS  ADS  Google Scholar 

  10. Gonzalez-Huizar, H., Velasco, A. A., Peng, Z. & Castro, R. R. Remote triggered seismicity caused by the 2011 M9.0 Tohoku-Oki, Japan earthquake. Geophys. Res. Lett. 39, L10302 (2012)

    Article  ADS  Google Scholar 

  11. Parsons, T. & Velasco, A. A. Absence of remotely triggered large earthquakes beyond the mainshock region. Nature Geosci. 4, 312–316 (2011)

    Article  CAS  ADS  Google Scholar 

  12. Lin, C.-H. Remote triggering of the Mw 6.9 Hokkaido Earthquake as a Result of the Mw 6.6 Indonesian Earthquake on September 11, 2008. Terr. Atmos. Ocean Sci. 23, 283–290 (2012)

    Article  Google Scholar 

  13. McGuire, J. & Beroza, G. A rogue earthquake off Sumatra. Science 336, 1118–1119 (2012)

    Article  CAS  ADS  Google Scholar 

  14. Kiser, E. Preliminary Rupture Modelling of the April 11, 2012 Sumatran Earthquakes. (2012)

  15. Wang, D., Mori, J. & Ohmi, S. Rupture Process of the April 11, 2012 Sumatra (Mw 8.6) Earthquake Imaged with Back-Projection of Hi-net Data. (2012)

  16. Meng, L. Ampuero, J.-P., Duputel, Z., Luo, Y. & Tsai, V. C. Earthquake in a maze: compressional rupture branching during the 2012 Mw 8.6 Sumatra earthquake. Science 337, 724–726 (2012)

    Article  CAS  ADS  Google Scholar 

  17. Incorporated Research Institutions for Seismology. Back projections for MW 8.7 off W coast of Northern Sumatra. (2012)

  18. Yue, H., Lay, T. & Koper, K. D. En échelon and orthogonal fault ruptures of the 11 April 2012 great interplate earthquake. Nature (this issue)

  19. Delescluse, M. et al. Intra-oceanic seismicity off Sumatra boosted by the Banda–Aceh megathrust. Nature (this issue)

  20. Kanamori, H. The energy release in great earthquakes. J. Geophys. Res. 82, 2981–2987 (1977)

    Article  ADS  Google Scholar 

  21. Gomberg, J. & Johnson, P. Dynamic triggering of earthquakes. Nature 437, 830 (2005)

    Article  CAS  ADS  Google Scholar 

  22. Hill, D. P. & Prejean, S. in Earthquake Seismology (ed. Schubert, G. ) 258–288 (Treatise on Geophysics 4, Elsevier, 2007)

    Google Scholar 

  23. Dahlen, F. A. & Tromp, J. Theoretical Global Seismology Ch. 11 (Princeton Univ. Press, 1998)

    Google Scholar 

  24. Gonzalez-Huizar, H. & Velasco, A. A. Dynamic triggering: stress modeling and a case study. J. Geophys. Res. 116, B02304 (2011)

    Article  ADS  Google Scholar 

  25. Engdahl, E. E. & Villaseñor, A. in International Handbook of Earthquake and Engineering Seismology (ed. Lee, W. H. K. ) 665–690 (Academic, 2002)

    Book  Google Scholar 

  26. Shelly, D. R., Peng, Z., Hill, D. P. & Aiken, C. Triggered creep as a possible mechanism for delayed dynamic triggering of tremor and earthquakes. Nature Geosci. 4, 384–388 (2011)

    Article  CAS  ADS  Google Scholar 

  27. Peng, Z. & Gomberg, J. An integrated perspective of the continuum between earthquakes and slow-slip phenomena. Nature Geosci. 3, 599–607 (2010)

    Article  CAS  ADS  Google Scholar 

  28. Peng, Z., Vidale, J. E., Wech, A. G., Nadeau, R. M. & Creager, K. C. Remote triggering of tremor along the San Andreas fault in central California. J. Geophys. Res. 114, B00A06 (2009)

    Article  ADS  Google Scholar 

  29. Velasco, A. A., Ammon, C. J., Farrell, J. & Pankow, K. Rupture directivity of the November 3, 2002 Denali Fault earthquake determined from surface waves. Bull. Seismol. Soc. Am. 94, S293–S299 (2004)

    Article  Google Scholar 

  30. Koss, H. & Nettles, M. Global CMT Project Moment Tensor Solution: April 11, 2012, Off W Coast of Northern Sumatra, MW = 8.6. (2012)

  31. Jaeger, J. C. & Cook, N. G. W. Fundamentals of Rock Mechanics Vol. 33 (Chapman and Hall, 1984)

    Google Scholar 

  32. Chlieh, M. et al. Coseismic slip and afterslip of the Great (Mw 9.15) Sumatra-Andaman earthquake of 2004. Bull. Seismol. Soc. Am. 97 (1a). S152–S173 (2007)

    Article  Google Scholar 

  33. Gardner, J. K. & Knopoff, L. Is the sequence of earthquakes in southern California, with aftershocks removed, Poissonian? Bull. Seismol. Soc. Am. 64, 1363–1367 (1974)

    Google Scholar 

  34. Friederich, W. & Dalkolmo, J. Complete synthetic seismograms for a spherically symmetric earth by a numerical computation of the Greens function in the frequency domain. Geophys. J. Int. 122, 537–550 (1995)

    Article  ADS  Google Scholar 

  35. Dziewonski, A. M., Chou, T.-A. & Woodhouse, J. H. Determination of earthquake source parameters from waveform data for studies of global and regional seismicity. J. Geophys. Res. 86, 2825–2852 (1981)

    Article  ADS  Google Scholar 

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Epicentres and magnitudes of seismic events were obtained from the NEIC catalogue. Seismic waveform data presented in Supplementary Information were obtained from the Incorporated Research Institutions for Seismology (IRIS) Data Management Center. We thank T. Hanks, R. Harris, A. Michael, T. Parsons and P. Stark for their comments on a preliminary draft. V.S. works under contract at the US Geological Survey.

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F.F.P. initiated the study and performed all seismic-wave analysis. F.F.P., R.S.S. and V.S. contributed equally to earthquake catalogue analysis. All authors discussed the results and helped write the manuscript.

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Correspondence to Fred F. Pollitz.

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Pollitz, F., Stein, R., Sevilgen, V. et al. The 11 April 2012 east Indian Ocean earthquake triggered large aftershocks worldwide. Nature 490, 250–253 (2012).

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