Abstract
In northern Italy in 1997, two earthquakes of magnitudes 5.7 and 6 (separated by nine hours) marked the beginning of a sequence that lasted more than 30 days, with thousands of aftershocks including four additional events with magnitudes between 5 and 6. This normal-faulting sequence is not well explained with models of elastic stress transfer1,2, particularly the persistence of hanging-wall seismicity3 that included two events with magnitudes greater than 5. Here we show that this sequence may have been driven by a fluid pressure pulse generated from the coseismic release of a known deep source4 of trapped high-pressure carbon dioxide (CO2). We find a strong correlation between the high-pressure front and the aftershock hypocentres over a two-week period, using precise hypocentre locations5 and a simple model of nonlinear diffusion. The triggering amplitude (10–20 MPa) of the pressure pulse overwhelms the typical (0.1–0.2 MPa) range from stress changes in the usual stress triggering models1,6. We propose that aftershocks of large earthquakes in such geologic environments may be driven by the coseismic release of trapped, high-pressure fluids propagating through damaged zones created by the mainshock. This may provide a link between earthquakes, aftershocks, crust/mantle degassing and earthquake-triggered large-scale fluid flow.
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References
- 1
Stein, R. S. The role of stress transfer in earthquake triggering. Nature 402, 605–609 (1999)
- 2
Cocco, M., Nostro, C. & Ekstrom, G. Static stress changes and fault interaction during the 1997 Umbria-Marche earthquake sequence. J. Seismol. 4, 501–516 (2000)
- 3
Chiaraluce, L., Ellsworth, W. L., Chiarabba, C. & Cocco, M. Imaging the complexity of an active normal fault system; the 1997 Colfiorito Central Italy case study. J. Geophys. Res. B 6, 10.1029/2002JB002166 (2003)
- 4
Chiodini, R. & Cioni, G. Gas geobarometry for hydrothermal systems and its application to various Italian geothermal areas. Appl. Geochem. 4, 564–572 (1989)
- 5
Waldhauser, F. & Ellsworth, W. L. A double-difference earthquake location algorithm: Method and application to the Northern Hayward Fault, California. Bull. Seismol. Soc. Am. 90, 1353–1368 (2000)
- 6
Toda, S., Stein, R. & Saglya, T. Evidence from the AD 2000 Izu islands earthquake swarm that stressing rate governs seismicity. Nature 419, 58–61 (2002)
- 7
Collettini, C. Structural permeability control on the post-seismic fluid discharge and aftershocks triggering; hypotheses for the 1997 Colfiorito earthquakes. Boll. Soc. Geol. It. 1, 873–880 (2002)
- 8
Sibson, R. H. Fault-valve behavior and the hydrostatic-lithostatic fluid pressure interface. Earth Sci. Rev. 32, 141–144 (1992)
- 9
Cox, S. F. Faulting processes at high fluid pressures: An example of fault valve behavior from the Wattle Gully Fault, Victoria, Australia. J. Geophys. Res. 100, 12841–12859 (1995)
- 10
Miller, S. A., Nur, A. & Olgaard, D. L. Earthquakes as a coupled shear stress-high pore pressure dynamical system. Geophys. Res. Lett. 23, 197–200 (1996)
- 11
Streit, J. E. & Cox, S. F. Fluid pressures at hypocenters of moderate to large earthquakes. J. Geophys. Res. 106, 2235–2243 (2001)
- 12
Reuter, K. J., Giese, P. & Closs, H. Lithosphere split in the descending plate; observations from the Northern Apennines. Tectonophysics 64, T1–T9 (1980)
- 13
Mirabella, F. & Pucci, S. Integration of geological and geophysical data along two sections crossing the region of the 1997–98 Umbria-Marche earthquake sequence. Boll. Soc. Geol. It. 1, 891–900 (2002)
- 14
Chiodini, G., Frondini, F., Cardellini, C., Parello, F. & Peruzzi, L. Rate of diffuse carbon dioxide Earth degassing estimated from carbon balance of regional aquifers: The case of central Apennine, Italy. J. Geophys. Res. 105, 8423–8434 (2000)
- 15
Quattrocchi, F. In search of evidence of deep fluid discharges and pore pressure evolution in the crust to explain the seismicity style of the Umbria-Marche, 1997–1998 seismic sequence (Central Italy). Ann. Geophys. 42, 609–636 (1999)
- 16
Bräuer, K., Kämpf, H., Strauch, G. & Weise, S. M. Isotopic evidence (3He/4He, 13 C CO 2 ) of fluid-triggered intraplate seismicity. J. Geophys. Res. 108, 10.1029/2002JB002077 (2003)
- 17
Baisch, S. & Harjes, H.-P. A model for fluid-injection-induced seismicity at the KTB, Germany. Geophys. J. Int. 152, 160–170 (2003)
- 18
Rice, J. R. in Fault Mechanics and Transport Properties of Rock (eds Evans, B. & Wong, T.-f.) 476–503 (Academic, San Diego, 1992)
- 19
Revil, A. & Cathles, L. M. III Fluid transport by solitary waves along growing faults. A field example from the South Eugene Island Basin, Gulf of Mexico. Earth Planet. Sci. Lett. 202, 321–335 (2002)
- 20
Manning, C. E. & Ingebritsen, S. E. Permeability of the continental crust: Implications of geothermal data and metamorphic systems. Rev. Geophys. 37, 127–150 (1999)
- 21
Noir, J., Jacques, E., Bèkri, S., Adler, P. M. & King, G. C. P. Fluid flow triggered migration of events in the 1989 Dobi earthquake sequence of Central Afar. Geophys. Res. Lett. 24, 2335–2338 (1997)
- 22
Lee, H. S. & Cho, T. F. Hydraulic characteristics of rough fractures in linear flow under normal and shear load. Rock Mech. Rock Eng. 35, 299–318 (2002)
- 23
Segall, P. & Rice, J. R. Dilatancy, compaction, and slip instability of a fluid infiltrated fault. J. Geophys. Res. 100, 22155–22171 (1995)
- 24
Dieterich, J. A constitutive law for rate of earthquake production and its application to earthquake clustering. J. Geophys. Res. 99, 2601–2618 (1994)
- 25
Nur, A. & Booker, J. R. Aftershocks caused by pore fluid flow? Science 175, 885–887 (1972)
- 26
Bosl, W. J. & Nur, A. Aftershocks and pore fluid diffusion following the 1992 Landers earthquake. J. Geophys. Res. 107, 10.1029/2001JB000155 (2002)
- 27
Cocco, M. & Rice, J. R. Pore pressure and poroelasticity in Coulomb analysis of earthquake interactions. J. Geophys. Res. 107, 10.1029/2000JB000138 (2002); correction 10.1029/2002JB002319 (2003)
- 28
Wong, T.-f., Ko, S.-c. & Olgaard, D. L. Generation and maintenance of pore pressure excess in a dehydrating system, 2, Theoretical analysis. J. Geophys. Res. 102, 841–852 (1997)
- 29
Miller, S. A., van der Zee, W., Olgaard, D. L. & Connolly, J. A. D. A fluid-pressure controlled feedback model of dehydration reactions: Experiments, modelling, and application to subduction zones. Tectonophysics 370, 241–251 (2003)
- 30
Jaeger, J. C. & Cook, N. G. W. Rock Mechanics (Chapman and Hall, London, 1979)
Acknowledgements
We thank C. H. Scholz for comments, and D. Giardini, Y. Y. Podladchikov, J. A. D. Connolly, T. Kohl, K. Evans, G. Hillers and N. Deichmann for discussions.Authors' contributions C.C., structural geology and concept development; L.C. and M.C., aftershock data; M.B., structural geology; B.J.P.K., numerical model development.
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Miller, S., Collettini, C., Chiaraluce, L. et al. Aftershocks driven by a high-pressure CO2 source at depth. Nature 427, 724–727 (2004). https://doi.org/10.1038/nature02251
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