Abstract
KNOWLEDGE of the viscosity structure of the Earth's mantle is important for constraining models of mantle convection and isostatic rebound. Here we show that seismicity around the margins of deglaciated areas provides a constraint on the viscosity of the lower mantle, in addition to those previously proposed1,2. Calculations using a spherical, viscoelastic Earth model show that the present-day magnitude of the stress fields induced in the lithosphere beneath the (now-disappeared) Laurentide and Fennoscandian ice sheets is very sensitive to the value of the lower-mantle viscosity. Stresses of ∼100 bar, sufficient to cause seismicity, can still remain in the lithosphere for lower-mantle viscosities greater than ∼1022 Pa s; for lower-mantle viscosities of ∼1021 Pa s, only a few tens of bars of stress persist in the lithosphere today. This influence of lower-mantle viscosity on the state of stress in the lithosphere also has implications for the migration of stress from earthquakes, and hence for earthquake recurrence times.
This is a preview of subscription content, access via your institution
Access options
Subscribe to this journal
Receive 51 print issues and online access
$199.00 per year
only $3.90 per issue
Buy this article
- Purchase on Springer Link
- Instant access to full article PDF
Prices may be subject to local taxes which are calculated during checkout
Similar content being viewed by others
References
Cathles, L. M. III The Viscosity of the Earth's Mantle (Princeton University Press, 1975).
Richards, M. A. & Hager, B. H. J. geophys. Res. 89, 5987–6002 (1984).
Peltier, W. R. & Tushingham, A. M. Science 244, 806–810 (1989).
Lambeck, K., Johnston, P. & Nakada, M. Geophys. J. 103, 451–468 (1990).
Gutenberg, B. & Richter, C. F. Seismicity of the Earth and Associated Phenomena (Princeton University Press, 1949).
Hasegawa, H. S. & Hermann, R. B. in Earthquakes at North-Atlantic Passive Margins: Neotectonics and Postglacial Rebound (eds Gregersen, S. & Basham, P. W.) 547–562 (Kluwer, Dordrecht, 1989).
Stein, S., Sleep, N., Geller, R., Wang, S. & Kroeger, G. Geophys. Res. Lett. 5, 537–540 (1979).
Bungum, H. in Earthquakes at North-Atlantic Passive Margins: Neotectonics and Postglacial Rebound (eds Gregersen, S. & Basham, P. W.) 501–519 (Kluwer, Dordrecht, 1989).
Hager, B. H. & O'Connell, R. J. J. geophys. Res. 8, 1031–1048 (1979).
Wu, J. & Yuen, D. A. Geophys. J. 104, 331–350 (1991).
Wahlström, R. in Earthquakes at North-Atlantic Passive Margins: Neotectonics and Postglacial Rebound (eds Gregersen, S. & Basham, P. W.) 467–482 (Kluwer, Dordrecht, 1989).
Spada, G., Yuen, D. A., Sabadini, R. C. A., Morin, P. J. & Gasperini, P. Mathematica J. 1, 65–69 (1990).
Karato, S. Phys. Earth planet. Inter. 55, 234–240 (1989).
Yuen, D. A., Sabadini, R. C. A., Gasperini, P. & Boschi, E. V. J. geophys. Res. 91, 11420–11438 (1986).
Karner, G. D., Steckler, M. A. & Thorne, J. A. Nature 304, 250–253 (1983).
Ricard, Y., Vigny, C. & Froidevaux, C. J. geophys. Res. 94, 13739–13754 (1989).
Nur, A. & Mavko, G. Science 183, 204–206 (1974).
Savage, J. C. & Prescott, W. H. J. geophys. Res. 83, 3369–3376 (1978).
Bonafede, M., Dragoni, M. & Morelli, A. J. geophys. Res. 91, 6396–6404 (1986).
Author information
Authors and Affiliations
Rights and permissions
About this article
Cite this article
Spada, G., Yuen, D., Sabadini, R. et al. Lower-mantle viscosity constrained by seismicity around deglaciated regions. Nature 351, 53–55 (1991). https://doi.org/10.1038/351053a0
Received:
Accepted:
Issue Date:
DOI: https://doi.org/10.1038/351053a0
This article is cited by
-
Crust Macrofracturing as the Evidence of the Last Deglaciation
Pure and Applied Geophysics (2023)
-
Glacial Isostatic Adjustment and Contemporary Sea Level Rise: An Overview
Surveys in Geophysics (2017)
-
Excitation of true polar wander by subduction
Nature (1992)
Comments
By submitting a comment you agree to abide by our Terms and Community Guidelines. If you find something abusive or that does not comply with our terms or guidelines please flag it as inappropriate.