Abstract
Large earthquakes alter the stress in the surrounding crust, leading to triggered earthquakes and aftershocks1,2,3. A number of time-dependent processes, including afterslip, pore-fluid flow and viscous relaxation of the lower crust and upper mantle, further modify the stress and pore pressure near the fault, and hence the tendency for triggered earthquakes4,5. It has proved difficult, however, to distinguish between these processes on the basis of direct field observations, despite considerable effort6. Here we present a unique combination of measurements consisting of satellite radar interferograms7 and water-level changes in geothermal wells following two magnitude-6.5 earthquakes in the south Iceland seismic zone. The deformation recorded in the interferograms cannot be explained by either afterslip or visco-elastic relaxation, but is consistent with rebound of a porous elastic material in the first 1–2 months following the earthquakes. This interpretation is confirmed by direct measurements which show rapid (1–2-month) recovery of the earthquake-induced water-level changes. In contrast, the duration of the aftershock sequence is projected to be ∼3.5 years, suggesting that pore-fluid flow does not control aftershock duration. But because the surface strains are dominated by pore-pressure changes in the shallow crust, we cannot rule out a longer pore-pressure transient at the depth of the aftershocks. The aftershock duration is consistent with models of seismicity rate variations based on rate- and state-dependent friction laws.
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References
Harris, R. A., Simpson, R. W. & Reasenberg, P. A. Influence of static stress changes on earthquake locations in southern California. Nature 375, 221–224 (1995)
Dieterich, J. A constitutive law for rate of earthquake production and its application to earthquake clustering. J. Geophys. Res. 99, 2601–2618 (1994)
Toda, S., Stein, R. S. & Sagiya, T. Evidence from the AD 2000 Izu islands earthquake swarm that stressing rate governs seismicity. Nature 419, 58–61 (2002)
Freed, A. M. & Lin, J. Delayed triggering of the 1999 Hector Mine earthquake by viscoelastic stress transfer. Nature 411, 180–183 (2001)
Nur, A. & Booker, J. R. Aftershocks caused by pore fluid flow? Science 175, 885–887 (1972)
Pollitz, F. F., Wicks, C. & Thatcher, W. Mantle flow beneath a continental strike-slip fault: Post-seismic deformation after the 1999 Hector Mine earthquake. Science 293, 1814–1818 (2001)
Zebker, H., Rosen, P., Goldstein, R., Gabriel, A. & Werner, C. On the derivation of coseismic displacement fields using differential radar interferometry: The Landers earthquake. J. Geophys. Res. 99, 19617–19643 (1994)
Einarsson, P. Earthquakes and present-day tectonism in Iceland. Tectonophysics 189, 261–279 (1991)
Einarsson, P. & Eiríksson, J. Earthquake fractures in the Districts Land and Rangárvellir in the South Iceland Seismic Zone. Jökull 32, 113–119 (1982)
Pedersen, R., Sigmundsson, F., Feigl, K. L. & Árnadóttir, T. Coseismic interferograms of two MS = 6.6 earthquakes in the South Iceland Seismic Zone, June 2000. Geophys. Res. Lett. 28, 3341–3344 (2001)
Pedersen, R., Jónsson, S., Árnadóttir, T., Sigmundsson, F. & Feigl, K. Fault slip distribution of two June 2000 Mw = 6.5 earthquakes in South Iceland estimated from joint inversion of InSAR and GPS measurements. Earth Planet. Sci. Lett. (in the press)
Árnadóttir, T. et al. Crustal deformation measured by GPS in the South Iceland Seismic Zone due to two large earthquakes in June 2000. Geophys. Res. Lett. 28, 4031–4033 (2001)
Einarsson, P., Björnsson, S., Foulger, G., Stefánsson, R. & Skaftadóttir, Th. in Earthquake Prediction—An International Review Vol. 4 (eds Simpson, D. W. & Richards, P. G.) 141–151 (American Geophysical Union, Washington DC, 1981)
Bürgmann, R. et al. Time-space variable afterslip on and deep below the Izmit earthquake rupture. Bull. Seismol. Soc. Am. 92, 126–137 (2002)
Peltzer, G., Rosen, P., Rogez, F. & Hudnut, K. Poro-elastic rebound along the Landers 1992 earthquake surface rupture. J. Geophys. Res. 103, 30131–30145 (1998)
Sigmundsson, F. Post-glacial rebound and asthenosphere viscosity in Iceland. Geophys. Res. Lett. 18, 1131–1134 (1991)
Sigmundsson, F. & Einarsson, P. Glacio-isostatic crustal movements caused by historical volume change of the Vatnajokull ice cap, Iceland. Geophys. Res. Lett. 19, 2123–2126 (1992)
Pollitz, F. F. & Sacks, I. S. Viscosity structure beneath northeast Iceland. J. Geophys. Res. 101, 17771–17793 (1996)
Hofton, M. & Foulger, G. R. Postrifting anelastic deformation around the spreading plate boundary, north Iceland: 1. Modeling of the 1987-1992 deformation field using a visco-elastic earth structure. J. Geophys. Res. 101, 25403–25421 (1996)
Björnsson, G., Flovenz, Ó. G., Saemundsson, K. & Einarsson, E. H. in Proc. 26th Workshop on Geothermal Reservoir Engineering SGP-TR-168, 327–334 (Stanford University, Stanford, 2001)
Roeloffs, E. Poroelastic techniques in the study of earthquake-related hydrologic phenomena. Adv. Geophys. 27, 135–195 (1996)
Clifton, A. & Einarsson, P. in Autumn Meeting 2000—Abstracts (ed Jónsson, S. S.) 1 (Geoscience Society of Iceland, Reykjavík, 2000)
Segall, P. Induced stresses due to fluid extraction from axisymmetric reservoirs. Pure Appl. Geophys. 139, 535–560 (1992)
Rice, J. R. & Cleary, M. P. Some basic stress diffusion solutions for fluid-saturated elastic porous media with compressible constituents. Rev. Geophys. Space Sci. 14, 227–241 (1976)
DeMets, C., Gordon, R. G., Argus, D. F. & Stein, S. Current plate motions. Geophys. J. Int. 101, 425–478 (1990)
Dziewonski, A. M., Ekstrom, G. & Maternovskaya, N. Centroid-moment tensor solutions for April-June 2000. Phys. Earth Planet. Inter. 123, 1–14 (2001)
Chen, C. W. & Zebker, H. A. Two-dimensional phase unwrapping with use of statistical models for cost functions in nonlinear optimization. J. Opt. Soc. Am. 18, 338–351 (2001)
Wang, H. F. Theory of Linear Poro-Elasticity with Applications to Geomechanics and Hydrogeology (Princeton Univ. Press, Princeton, 2001)
Acknowledgements
We thank the European Space Agency for providing the SAR data. We also thank G. Guðmundsson and R. Stefánsson for providing preliminary earthquake locations from the South Iceland Lowland (SIL) seismic network; A. Clifton and P. Einarsson for providing data of the mapped surface ruptures; F. Sigmundsson, T. Árnadóttir, K. Ágústsson, E. Roeloffs and K. Feigl for discussions; and R. Bürgmann for comments and suggestions that improved the paper.
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Jónsson, S., Segall, P., Pedersen, R. et al. Post-earthquake ground movements correlated to pore-pressure transients. Nature 424, 179–183 (2003). https://doi.org/10.1038/nature01776
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DOI: https://doi.org/10.1038/nature01776
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