Deformation of the lithosphere is characterised by elastic, non-linear
viscous and plastic material behaviour. The representation of this complex
rheology is a challenge for numerical models of tectonic processes and it is
important, therefore, to test rheology assumptions and implementations. A
comparison of results run with different codes for a well-defined and
constrained setup may help to establish code-independent results and
improve codes by learning from any differences.
No benchmark exists to date of Earth Science codes for plasticity implementations. In 2005*, we proposed to design a Mohr-Coulomb plasticity experiment for comparing results of different numerical codes with different numerical techniques.
The experiment should:
All participating codes would first be required to pass some rheology (viscous, viscoelastic or elastoplastic) tests to ensure that all codes have the same common basis before continuing to more complex setups.
*Susanne Buiter, Boris Kaus, and Neil Mancktelow, 2005, Discussion on designing a plasticity benchmark experiment, 9th International workshop on Numerical Modeling of Mantle Convection and Lithosphere Dynamics, Erice, Italy.
Example test: Circular inclusion
|Example of experimental setup||Gango - Boris Kaus, PhD thesis, 2005|
Analytical solutions for pure and simple shear are available for
elastic, viscous and viscoelastic rheologies from Schmid and
Podladchikov , 2003, Geophys J Int 155.
The circular geometry of the inclusion may be difficult to implement in
codes with quadrilateral elements.
05.07.2016: This has not been followed up so far, but suggestions and especially volunteers for organising a plasticitiy benchmark are very welcome! Just drop an e-mail to Susanne Buiter (susanne.buiter-at-ngu.no).