The permanent and dynamic (transient) stress changes inferred to trigger earthquakes are usually orders of magnitude smaller than the stresses relaxed by the earthquakes themselves, implying that triggering occurs on critically stressed faults1,2,3,4. Triggered seismicity rate increases may therefore be most likely to occur in areas where loading rates are highest and elevated pore pressures, perhaps facilitated by high-temperature fluids, reduce frictional stresses and promote failure5,6,7. Here we show that the 2002 magnitude M = 7.9 Denali, Alaska, earthquake triggered widespread seismicity rate increases throughout British Columbia and into the western United States. Dynamic triggering by seismic waves should be enhanced in directions where rupture directivity focuses radiated energy, and we verify this using seismic and new high-sample GPS recordings of the Denali mainshock. These observations are comparable in scale only to the triggering caused by the 1992 M = 7.4 Landers, California, earthquake1, and demonstrate that Landers triggering did not reflect some peculiarity of the region or the earthquake. However, the rate increases triggered by the Denali earthquake occurred in areas not obviously tectonically active, implying that even in areas of low ambient stressing rates, faults may still be critically stressed and that dynamic triggering may be ubiquitous and unpredictable.
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Hill, D. P. et al. Remote seismicity triggered by the M7.5 Landers, California earthquake of June 28, 1992. Science 260, 1617–1623 (1993)
Gomberg, J., Beeler, N. & Blanpied, M. On rate-state and Coulomb failure models. J. Geophys. Res. 105, 7857–7872 (2000)
Huc, M. & Main, I. G. Anomalous stress diffusion in earthquake triggering: Correlation length, time dependence, and directionality. J. Geophys. Res. 108(B7), doi:10.1029/2001JB001645 (2003)
Belardinelli, M. E., Bizzarri, A. & Cocco, M. Earthquake triggering by static and dynamic stress changes. J. Geophys. Res. 108(B3), doi:1029/2002JB001779 (2003)
Cocco, M. & Rice, J. R. Pore pressure and poroelasticity effects in Coulomb stress analysis of earthquake interactions. J. Geophys. Res. 107(B2), doi:10.1029/2000JB000138 (2002)
Streit, J. E. & Cox, S. F. Fluid pressures at hypocenters of moderate to large earthquakes. J. Geophys. Res. 106, 2235–2243 (2001)
Sturtevant, B., Kanamori, H. & Brodsky, E. E. Seismic triggering by rectified diffusion in geothermal systems. J. Geophys. Res. 101, 25269–25282 (1996)
Eberhart-Phillips, D. et al. The 2002 Denali Fault Earthquake, Alaska: A large magnitude, slip-partitioned event. Science 300, 1113–1118 (2003)
Ozacar, A. A., Beck, S. & Christiansen, D. H. Source process of the 3 November 2002 Denali fault earthquake (central Alaska) from teleseismic observations. Geophys. Res. Lett. 30, doi:10.1029/2003GL017272 (2003)
Riddihough, R. P. & Hyndman, R. D. in Geology of the Cordilleran Orogen in Canada (eds Gabrielse, H. & Yorath, C. J.) Ch. 13, no. 4, 435–455 (Geologic Survey of Canada, Geology of Canada, Ottawa, 1991)
Miller, M. M. et al. GPS-determination of along-strike variation in Cascadia margin kinematics: Implications for relative plate motion, subduction zone coupling, and permanent deformation. Tectonics 20, 161–176 (2001)
Anderson, J. G. et al. Seismicity in the western Great Basin apparently triggered by the Landers, California, earthquake 28 June 1992. Bull. Seismol. Soc. Am. 84, 863–891 (1994)
Flück, P, Hyndman, R. D. & Lowe, C. Effective elastic thickness Te of the lithosphere in western Canada. J. Geophys. Res. 108(B9), doi:1029/2002JB002201 (2003)
Seeber, L., Armbruster, J. G., Kim, W.-Y. & Barstow, N. The 1994 Cacoosing Valley earthquakes near Reading, Pennsylvania:A shallow rupture triggered by quarry unloading. J. Geophys. Res. 103, 24505–24521 (1998)
Hough, S. E., Seeber, L. & Armbruster, J. G. Intraplate triggered earthquakes: Observations and interpretation. Bull. Seismol. Soc. Am. 93, 2212–2221 (2003)
Townend, J. & Zoback, M. D. How faulting keeps the crust strong. Geology 28, 399–402 (2000)
Larson, K., Bodin, P. & Gomberg, J. Using 1 Hz GPS data to measure deformations caused by the Denali fault earthquake. Science 300, 1421–1424 (2003)
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)
Galbrielse, H., Monger, J. W. H., Wheeler, J. O. & Yorath, C. J. in Geology of the Cordilleran Orogen in Canada (eds Gabrielse, H. & Yorath, C. J.) Ch. 2, no. 4, 13–59 (Geologic Survey of Canada, Geology of Canada, Ottawa, 1991)
Gomberg, J. & Agnew, D. C. The accuracy of seismic estimates of dynamic strains from Pinon Flat Observatory, California, strainmeter and seismograph data. Bull. Seismol. Soc. Am. 86, 212–220 (1996)
The authors declare that they have no competing financial interests.
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Gomberg, J., Bodin, P., Larson, K. et al. Earthquake nucleation by transient deformations caused by the M = 7.9 Denali, Alaska, earthquake. Nature 427, 621–624 (2004) doi:10.1038/nature02335
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