TCD The Cryosphere Discussions TCD The Cryosphere Discuss. 1994-0440 Göttingen, Germany 10.5194/tcd-4-1635-2010 Do crustal deformations observed by GPS in Tierra del Fuego (Argentina) reflect glacial-isostatic adjustment? Mendoza L. 1 3 Richter A. 1 2 Hormaechea J. L. 1 3 Perdomo R. 1 3 Del Cogliano D. 1 3 Dietrich R. 2 Fritsche M. 2 Departamento de Astrometría, Facultad de Ciencias Astronómicas y Geofísicas, Universidad Nacional de La Plata, La Plata, Argentina Institut für Planetare Geodäsie, Technische Universität Dresden, Dresden, Germany CONICET, Argentina 10 09 2010 4 3 1635 1645 Copyright: © 2010 L. Mendoza et al. 2010 This work is licensed under the Creative Commons Attribution 3.0 Unported License. To view a copy of this licence, visit https://creativecommons.org/licenses/by/3.0/ This article is available from https://tc.copernicus.org/preprints/4/1635/2010/tcd-4-1635-2010.html The full text article is available as a PDF file from https://tc.copernicus.org/preprints/4/1635/2010/tcd-4-1635-2010.pdf

Vertical site velocities determined by geodetic GPS observations in the Lago Fagnano area, Tierra del Fuego main island, are interpreted with respect to their potential relation with the glacial-isostatic crustal response to ice mass changes. The spatial pattern of the uplift rates, in combination with the horizontal crustal deformation pattern, point towards a fault-tectonic rather than glacial-isostatic origin of the determined vertical crustal deformations. This implies rather small GIA effects pointing towards relatively small Holocene ice-mass changes in Tierra del Fuego. However, these findings are considered to be preliminary. They should be confirmed by additional observations covering an extended area with GPS sites.

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