Abstract
The episode of climate warming during the 20th century is documented by an ablation of the Vatnajökull ice cap, south-eastern Iceland. Due to the small thickness of the elastic lithosphere and the low viscosity of the asthenosphere below Iceland, the ablation resulted in a retarded land uplift of about 3–8 mm/a in the vicinity of the ice cap. This is confirmed by GPS campaigns carried out south of the ice cap in 1992 and 1996 (Sjöberg et al, 1999). Furthermore, a relative uplift of 12.4 cm along Lake Langisjór south-west of the ice cap was observed between 1959 and 1991 (Sigmundsson & Einarsson, 1992). In the present study, we use a compressible, self-gravitating, spherical earth model with Maxwell viscoelasticity and a load model parabolic in cross section and elliptic in plan view to interpret the observations in terms of viscosity stratification. Our results show that the lithosphere is 10 to 20 km in thickness and the asthenosphere is 7 × 1016 to 3 × 1018 Pas in viscosity.
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References
Dziewonski A. & Anderson D. Preliminary reference earth model. Physics of the Earth and Planetary Interiors, 25, 297–356, 1981.
Einarsson P., Sigmundsson F., Hofton M.A., Foulger G.R. & Jacoby W. An experiment in glacio-isostasy near Vatnajökull, Iceland, 1991. Jökull, 44, 29–39, 1996.
Einarsson P. Earthquakes and present-day tectonism in Iceland. Tectonophysics, 189, 261–279, 1991.
Foulger G.R., Jahn C.H., Seeber G., Einarsson P., Julian B.R. & Heki K. Post-rifting stress relaxation at the divergent plate boundary in Northeast Iceland. Nature, 358, 488–490, 1992.
Haskell N.A. The motion of a viscous fluid under a surface load. Physics, 6, 265–269, 1935.
Hofton M.A. & Foulger G.R. Postrifting anelastic deformation around the spreading plate boundary, north Iceland. 1. Modeling of the 1987–1992 deformation field using a viscoelastic Earth structure. Journal of Geophysical Research, 101, 25403–25421, 1996a.
Hofton M.A. & Foulger G.R. Postrifting anelastic deformation around the spreading plate boundary, north Iceland. 2. Implications of the model derived from the 1987–1992 deformation field. Journal of Geophysical Research, 101, 25423–25436, 1996b.
Malberg H. Meteorologie und Klimatologie. Springer-Verlag, Berlin, 1994.
Martinec Z. & Wolf D. Explicit form of the propagator matrix for a multi-layered, incompressible viscoelastic sphere. Tech. Rep. STR98/08, GeoForschungsZentrum Potsdam, 1998.
Menke W. Crustal isostasy indicates anomalous densities beneath Iceland. Geophysical Research Letters, 26, 1215–1218, 1999.
Paterson W.S.B. The Physics of Glaciers, 3rd edn. Elsevier Science, Oxford, 1994.
Pollitz F.F. & Sacks LS. Viscosity structure beneath northeast Iceland. Journal of Geophysical Research, 101, 17771–17793, 1996.
Sigmundsson F. Post-glacial rebound and asthenosphere viscosity in Iceland. Geophysical Research Letters, 18, 1131–1134, 1991.
Sigmundsson F. & Einarsson P. Glacio-isostatic crustal movements caused by historical volume change of the Vatnajökull ice cap, Iceland. Geophysical Research Letters, 19, 2123–2126, 1992.
Sjöberg L.E., Pan M., Asenjo E. & Erlingsson S. Glacial rebound at Vatnajökull, Iceland, studied by GPS campaigns in 1992 and 1996. Journal of Geodynamics, 29, 63–70, 2000.
Wolf D., Barthelmes F. & Sigmundsson F. Predictions of deformation and gravity changes caused by recent melting of the Vatnajökull ice cap, Island. In Segawa J., Fujimoto H. & Okubo S., eds., Gravity, Geoid and Marine Geodesy, Springer-Verlag, Berlin, pp. 311–319, 1997a.
Wolf D., Barthelmes F. & Sigmundsson F. Predictions of deformation and gravity variation caused by recent change of the Vatnajökull ice cap, Island. Compt. Rend. J. Luxemb. Geodyn., 82, 36–42, 1997b.
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Thoma, M., Wolf, D., Neumeyer, J. (2001). Inverting land uplift near Vatnajökull, Iceland, in terms of lithosphere thickness and viscosity stratification. In: Sideris, M.G. (eds) Gravity, Geoid and Geodynamics 2000. International Association of Geodesy Symposia, vol 123. Springer, Berlin, Heidelberg. https://doi.org/10.1007/978-3-662-04827-6_16
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DOI: https://doi.org/10.1007/978-3-662-04827-6_16
Publisher Name: Springer, Berlin, Heidelberg
Print ISBN: 978-3-642-07634-3
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