eCite Digital Repository

Steps in lithospheric thickness within eastern Australia, evidence from surface wave tomography


Fishwick, S and Heintz, M and Kennett, BLN and Reading, AM and Yoshizawa, K, Steps in lithospheric thickness within eastern Australia, evidence from surface wave tomography, Tectonics, 27, (4) pp. TC4009 . ISSN 0278-7407 (2008) [Refereed Article]

DOI: doi:10.1029/2007TC002116


A series of steps in the lithospheric thickness of eastern Australia are revealed by the latest seismic surface wave tomographic model and calculations of the horizontal gradient of shear wave speed. The new images incorporate data from the recent Tasmal experiment, improving resolution in continental Australia. Through comparisons with surface geology and geochemical studies, it is possible to infer that the steps in lithospheric thickness are related to boundaries between blocks of different age. The westernmost boundary marks the edge of the Archaean to Early-Proterozoic core of the continent. A second lithospheric boundary is observed in the central part of east Australia. To the west of this line, geochemical evidence suggests that there is Proterozoic lithospheric mantle, and this boundary may therefore represent the change from Proterozoic to Phanerozoic basement. The structure on the eastern margin of the continent is dominated by slow velocities, suggesting that in this area the continental lithosphere is very thin. There is a strong correlation between the slow wave speeds and the location of both the highest topography and recent volcanic activity. Inland of the continental margin, a zone of strong gradients in the seismic wave speed is observed, indicating a distinct step in lithospheric structure. If the step in lithospheric thickness was in place prior to volcanism, it may have acted as a boundary, with volcanism mainly occurring beneath the thinner lithosphere to the east. Copyright 2008 by the American Geophysical Union.

Item Details

Item Type:Refereed Article
Research Division:Earth Sciences
Research Group:Geophysics
Research Field:Seismology and seismic exploration
Objective Division:Expanding Knowledge
Objective Group:Expanding knowledge
Objective Field:Expanding knowledge in the earth sciences
UTAS Author:Reading, AM (Professor Anya Reading)
ID Code:53061
Year Published:2008
Web of Science® Times Cited:108
Deposited By:Centre for Ore Deposit Research - CODES CoE
Deposited On:2008-10-23
Last Modified:2011-11-28

Repository Staff Only: item control page