|Wosnitza, E. 2002. Data Analysis in Thermomechanical Analogue Modelling. Schellart, W. P. and Passchier, C. 2002. Analogue modelling of large-scale tectonic processes. Journal of the Virtual Explorer.|
Data Analysis in Thermomechanical Analogue Modelling
Elmar M. Wosnitza
Institut der Universität Freiburg,
Thermomechanical analogue modelling can offer new types of data, providing a way to reconstruct the stress field within the model. Recording the experiments with an infrared camera allows the thermal field of during deformation to be analysed. The materials used in thermomechanical analogue experiments were chosen to demonstrate temperature-dependent viscosities, to allow the required rheological profile due to the thermal gradient applied by the machine.
Extending known data-analysis procedures to account for irregular domains and sparse marker distributions, various strain parameters are extracted from the optical photographs, including the strain rate tensor. The viscosity distribution is obtained from the temperature field and from rheological material properties. Together with the strain-rate tensor, the viscosity allows the calculation of the stress field in the model.
Although the main purpose of this work was to set up the apparatus and to develop experimental working-procedures and data analysis, first experiments modelled simple orogenic scenarios. A modelled megathrust geometry corresponds well to seismic data from the Urals. Further models including an orogenic wedge are compared with Structures known from the Himalayas.
Keywords: Thermomechanical analogue modelling, data analysis