Speaker: Thorsten W Becker
I present results from mantle flow modeling of the Tethyan margin on a range of spatial scales. These models speak to the dynamics of mobile belts in the Mediterranean and the protracted convergence of the Indian plate with respect to Eurasia. By analyzing micro-plate motions and dynamic topography, we can explore how upper and whole mantle convection is expressed tectonically at the surface. Based on this analysis and related work, we propose that mountain belts can be classified between two end-members. Firstly, those of \u201cslab pull\u201d type, where subduction is mainly confined to the upper mantle, and rollback trench motion leads to moderately thick crustal stacks, such as in the Mediterranean. Secondly, those of \u201cslab suction\u201d type, where whole mantle convection cells (\u201cconveyor belts\u201d) lead to the more extreme expressions of orogeny, such as the largely thickened crust and high plateaux of present-day Tibet and the Altiplano. If our model is correct, the available geological records of orogeny can be used to decipher time-dependent mantle convection, with implications for plate tectonic heat transport and the super-continental cycle.<\/p>\n","protected":false},"excerpt":{"rendered":"