Through the combination of rare historical sea level observations collected during Sir Douglas Mawson’s 1911-1914 Australasian Antarctic Expedition, together with modern sea level data, space geodetic estimates of crustal displacement and modeling of coseismic and postseismic earthquake deformation, we present a contemporary analysis to constrain sea level and land level change over the twentieth century at Macquarie Island. We refine the source parameters of the Mw ~8.0 great earthquake of 23 December 2004 using estimates of coseismic displacements at regional GPS sites including HOB2 in Hobart. Modelling four years of post-2004.98 deformation constrains the oceanic upper mantle rheology. The 2000-2005 Macquarie Island GPS vertical velocity of -2.46 ± 0.64 mm/y is explained by ongoing postseismic deformation from Macquarie Ridge great earthquakes of 1989 and 1924. The twentieth century observed relative sea level rise of +4.8 ± 0.6 mm/y is consistent with an absolute sea level rise of +2.0 ± 0.8 mm/y.

Item Type:	Conference Extract
Keywords:	Macquarie Island, sea level rise, plate boundaries
Research Division:	Engineering
Research Group:	Geomatic engineering
Research Field:	Photogrammetry and remote sensing
Objective Division:	Expanding Knowledge
Objective Group:	Expanding knowledge
Objective Field:	Expanding knowledge in the environmental sciences
UTAS Author:	Burgette, RJ (Dr Reed Burgette)
ID Code:	65545
Year Published:	2010
Deposited By:	Geography and Environmental Studies
Deposited On:	2010-11-22
Last Modified:	2010-11-22
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