Abstract
A weakened zone in the lithosphere plunging into the mantle can lead to an earthquake after the application of a shear stress only in the case if the effective viscosity of this zone is very low. At low viscosity, in the short time that elapses after the application of stress, significant displacements of the walls of the zone emerge causing high-amplitude seismic waves. The Andrade law describing the transient creep under constant stress applied at the initial time instant leads to very low effective viscosity a few first seconds after the initial time instant. The effective viscosity also decreases due to the temperature rise in the weakened zone caused by the dissipative release of heat. However, this process is not rapid enough to noticeably change the temperature and effective viscosity in a short time.
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REFERENCES
Berckhemer, H., Auer, F., and Drisler, J., High-temperature anelasticity and elasticity of mantle peridotite, Phys. Earth Planet. Inter., 1979, vol. 20, pp. 48–59.
Birger, B.I., Rheology of the Earth and thermoconvective mechanism for sedimentary basins formation, Geophys. J. Int., 1998, vol. 134, pp. 1–12.
Birger, B.I., Excitation of thermoconvective waves in the continental lithosphere, Geophys. J. Int., 2000, vol. 140, pp. 24–36.
Birger, B.I., Attenuation of seismic waves and the universal rheological model of the Earth’s mantle, Izv., Phys. Solid Earth, 2007, vol. 43, no. 8, pp. 635–641.
Birger, B.I., Transient creep and convective instability of the lithosphere, Geophys. J. Int., 2012, vol. 191, pp. 909–922.
Birger, B.I., Temperature-dependent transient creep and dynamics of cratonic lithosphere, Geophys. J. Int., 2013, vol. 195, pp. 695–705.
Birger, B.I., Dinamika litosfery Zemli (Dynamics of the Earth’s Lithosphere), Moscow: Lenand, 2016.
Goetze, C., High temperature rheology of westerly granite, J. Geophys. Res., 1971, vol. 76, pp. 1223–1230.
Goetze, C. and Brace, W.F., Laboratory observations of high-temperature rheology of rocks, Tectonophysics, 1972, vol. 13, pp. 583–600.
Hobbs, B.E. and Ord, A., Plastic instabilities: implications for the origin of intermediate and deep focus earthquakes, J. Geophys. Res., 1988, vol. 89, pp. 10521–10540.
Jeffreys, H., A modification of Lomnitz’s law of creep in rocks, Geophys. J. R. Astron. Soc., 1958, vol. 1, pp. 92–95.
Karato, S., Deformation of Earth Materials. An Introduction to the Rheology of Solid Earth, Cambridge: Cambridge Univ. Press, 2008.
Lomnitz, C., Linear dissipation in solids, J. Appl. Phys., 1957, vol. 28, pp. 201–205.
Murrell, S.A.F., Rheology of the lithosphere—experimental indications, Tectonophysics, 1976, vol. 36, pp. 5–24.
Murrell, S.A.F. and Chakravarty, S., Some new rheological experiments on igneous rock at temperatures up to 1120°C, Geophys. J. R. Astron. Soc., 1973, vol. 34, pp. 211–250.
Turcotte, D.L. and Schubert, J., Geodynamics, New York: Wiley, 1982.
Weertman, J., Creep laws for the mantle of the Earth, Philos. Trans. R. Soc. London, 1978, vol. A288, pp. 9–26.
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Translated by M. Nazarenko
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Birger, B.I. Rapid Growth of the Shear Strain in Weakened Zones of the Lithosphere. Izv., Phys. Solid Earth 55, 397–402 (2019). https://doi.org/10.1134/S1069351319030029
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DOI: https://doi.org/10.1134/S1069351319030029