Plate reconstruction context for variations in geodynamic, magmatic and mineralisation processes

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Repeated amalgamation and splitting apart of continental crust through time via the 'supercontinent' cycle have influenced and/or controlled most aspects of earth’s evolution. Episodic occurrences of different mineral deposit types, igneous petrological associations and sediment basins are influenced by a variety of geodynamic controls, all of which appear to be interrelated but our understanding of the processes, spatial and temporal variations is limited, particularly as we move back in time. Quality of life in our modern lifestyles is dependent on the continued availability of natural resources which requires the discovery of additional mineral deposits, including ones in crustal domains not previously explored ('greenfields' terrains). A better representation of the interplay of geodynamic setting, mineralisation and sedimentary depositional environment is thus required. I and my students will utilise major compilations of data now available in various international databases and GIS data sets to address time intervals for which reconstructions are currently least well constrained and to assess new ways to work with data so as to refine plate reconstructions. An ultimate objective for my research is the development of a reconstruction model from present day to the Late Archaean. Specific components proposed for the next five years are: OBJECTIVE 1) Assess newly developed criteria for measurement of reconstruction quality by applying them to selected existing plate models. OBJECTIVE 2) Investigate the geographic, temporal and geodynamic setting of igneous rock lithogeochemistry to better delineate changing sources and processes which ought to help inform plate reconstruction models. OBJECTIVE 3) Develop an improved plate reconstruction model for parts of the Central Asian Orogenic Belt by ‘unfolding’ several major Palaeozoic oroclines. Current plate models over-simplify the geometry of plates from this region which limits our ability to reconstruct earlier time intervals. OBJECTIVE 4) Develop an improved plate reconstruction model for Meso- to Neo-Proterozoic time to link an existing model for Palaeoproterozoic ‘Nuna’ with models for Phanerozoic earth evolution. Data collated within the context of these topics will be compiled and made available for future research via existing international databases such as StratDB and DateView, both previously designed and developed by myself. Successful completion will require extensive collaboration with several international researchers with regional or discipline-specific expertise. A network of collaborators has been developed to assist with this and will be extended where necessary, particularly within the context of the recently approved IGCP 648 project of which I am a co-leader.