The role of elastic stored energy in controlling the long term rheological behaviour of the lithosphere

Regenauer-Lieb, Klaus, Weinberg, Roberto F. and Rosenbaum, Gideon (2012) The role of elastic stored energy in controlling the long term rheological behaviour of the lithosphere. Journal of Geodynamics, 55 66-75. doi:10.1016/j.jog.2011.08.003

Author Regenauer-Lieb, Klaus
Weinberg, Roberto F.
Rosenbaum, Gideon
Title The role of elastic stored energy in controlling the long term rheological behaviour of the lithosphere
Journal name Journal of Geodynamics   Check publisher's open access policy
ISSN 0264-3707
Publication date 2012-04-01
Year available 2011
Sub-type Article (original research)
DOI 10.1016/j.jog.2011.08.003
Open Access Status Not Open Access
Volume 55
Start page 66
End page 75
Total pages 10
Place of publication Kidlington, Oxford, United Kingdom
Publisher Pergamon
Language eng
Formatted abstract
The traditional definition of lithospheric strength is derived from the differential stresses required to form brittle and ductile structures at a constant strain rate. This definition is based on dissipative brittle and ductile deformation and does not take into account the ability of the lithosphere to store elastic strain. Here we show the important role of elasticity in controlling the long-term behaviour of the lithosphere. This is particularly evident when describing deformation in a thermodynamic framework, which differentiates between stored (Helmholtz free energy) and dissipative (entropy) energy potentials. In our model calculations we stretch a continental lithosphere with a wide range of crustal thickness (30–60 km) and heat flow (50–80 mW/m2) at a constant velocity. We show that the Helmholtz free energy, which in our simple calculation describes the energy stored elastically, converges for all models within a 25% range, while the dissipated energy varies over an order of magnitude. This variation stems from complex patterns in the local strain distributions of the different models, which together operate to minimize the Helmholtz free energy. This energy minimization is a fundamental material behaviour of the lithosphere, which in our simple case is defined by its elastic properties. We conclude from this result that elasticity (more generally Helmholtz free energy) is an important regulator of the long-term geological strength of the lithosphere.
Keyword Lithosphere
Numerical modelling
Continental strength
Q-Index Code C1
Q-Index Status Confirmed Code
Grant ID DP1094050
Institutional Status UQ
Additional Notes Available online 7 September 2011

Document type: Journal Article
Sub-type: Article (original research)
Collections: School of Earth Sciences Publications
Official 2012 Collection
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Citation counts: TR Web of Science Citation Count  Cited 9 times in Thomson Reuters Web of Science Article | Citations
Scopus Citation Count Cited 10 times in Scopus Article | Citations
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