Wed 20th September @ noon, Rm 312.222

Abstract:

If we accept that an assumption of thermodynamic equilibrium is reasonable for melt-bearing rocks (> or >>650 °C), phase equilibria modelling provides a powerful tool for the investigation of the processes and geodynamic environment in which they formed and evolved. Until now, quantitative constraints on such high-temperature processes using phase equilibria have mainly been confined to the realm of crustal metamorphism, and used siliciclastic source rocks (mudstone, greywacke, etc.), due to the availability of appropriate thermodynamic models for solid solution phases, including melt. The recent development of solution models for minerals and melt in ultramafic and mafic systems represents a huge advance, allowing consideration of more fundamental questions, including the origin and evolution of basaltic primary (’oceanic’) crust from melting of the mantle, and thereby more evolved (‘granitic’) primitive continental crust from the melting of primary mafic crust. This talk gives a couple of examples of the potential utility of these new models, combining phase equilibria calculations on mafic source rocks with trace element modelling to investigate early Earth processes.

Bio:

Tim joined the Department of Applied Geology in January 2014. Prior to arriving at Curtin he worked for six years as a post-doctoral scientist at the University of Mainz in Germany. Before that he co-owned and ran a pub in Graz, Austria. Tim obtained his Honours degree in 1992 from the University of Derby in England. He was awarded his PhD in 1999 from the same institution for a thesis entitled “Partial melting of Dalradian pelitic migmatites from the Fraserburgh–Inzie Head area of Buchan, north-east Scotland”.