Lead supervisor: Alex Copley, Earth Sciences
Co-supervisor: Marie Edmonds, Earth Sciences; Owen Weller, Earth Sciences
Brief summary:
This project will produce a geodynamic understanding of the formation of critical metal deposits, and so pave the way to replacing empirical prospecting methods with a process-based view of the physical and chemical evolution of the lithosphere.
Importance of the area of research concerned:
The increasing need for critical metals as part of the transition to a sustainable energy supply and transport network are well known. However, one of the biggest limitations on current progress is the availability of the minerals that host these metals, in terms of both volumes being produced and the geo-political consequences of where they are currently mined. The majority of the existing deposits have been discovered by traditional prospecting methods. This project will aim to produce the unified physical and chemical understanding of critical metal cycling within the dynamically-evolving lithosphere, which will pave the way for a new process-based understanding of mineral prospectivity. In particular, this project will work at the scale of the entire lithosphere, rather than being limited to individual deposits. It will use cutting-edge techniques to study the deformation and thermal evolution of the lithosphere, and igneous and metamorphic processes. By uniting these fields, it will be possible to establish the factors that control the behaviour of critical metals, and so the conditions required to form important deposits.
Project summary :
The formation of critical mineral deposits (e.g. lithium, rare earth elements, tin; https://www.gov.uk/government/publications/uk-critical-mineral-strategy) depends on a complex interplay of igneous, metamorphic, hydrothermal, and deformation processes. Recent years have seen dramatic progress in all of these separate fields, including a new understanding of lithosphere deformation dynamics, new thermodynamic models of minerals, melts, and aqueous fluids, and new insights into the coupled igneous and metamorphic evolution of intrusions and their surroundings. This project will unite these recent advances to examine the conditions required for the formation of critical minerals in important concentrations. Specifically, the student will establish the combination of source, transport, and emplacement processes that are the prerequisites for the formation of important deposits.
What will the student do?:
The student will being by integrating existing models of deformation dynamics, temperature, and mineral/melt phase equilibria into a coherent physical and chemical model framework. It will then be possible to run a series of models, varying the governing parameters (e.g. lithosphere composition, melt transport dynamics, deformation history, etc) and examine the range of resulting outcomes. These model predications can then be compared to a compilation of the world’s important critical mineral deposits. These comparisons will reveal the combinations of governing parameters that result in significant critical mineral concentrations. The models will then be able to be used in a predictive sense, in which the history and conditions required for critical mineral formation can be defined, and therefore regional-scale prospectivity maps can be produced. This methodology has the potential to provide not only a process-based understanding of the formation of critical mineral deposits, but also could provide a new basis for future exploration targeting.
References - references should provide further reading about the project:
A. Copley, O. Weller, and H. Bain, Diapirs of crystal-rich slurry explain granite emplacement temperature and duration, Scientific Reports, doi:10.1038/s41598-023-40805-2, 2023
C. Penney and A. Copley, Lateral variations in lower crustal strength control the temporal evolution of mountain ranges: examples from south-east Tibet, Geochemistry, Geophysics, Geosystems, 22, doi:10.1029/2020GC009092, 2021
A. Whyte, O. Weller, A. Copley, and M. St-Onge, Quantifying Water Diffusivity and Metamorphic Reaction Rates Within Mountain Belts, and Their Implications for the Rheology of Cratons, Geochemistry, Geophysics, Geosystems, 22, doi:10.1029/2021GC009988, 2021
Applying
You can find out about applying for this project on the Department of Earth Sciences page.