Formation of magmatic oxide deposits

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Magmatic oxide deposits are important sources of titanium (Ti) and vanadium (V), extracted from oxide minerals (ilmenite and magnetite, respectively), and phosphorous (P), from apatite. The crystallization and accumulation of these minerals occurred in ancient magma chambers, termed igneous intrusions, in the Earth's crust. Yet many of the fundamental processes involved in the formation of this class of mineral deposit and their host intrusions remain unresolved and are highly debated over. My research aim is to improve our understanding of these processes using an innovative approach: the analysis of trace elements in the ore minerals themselves. Over the next 5 years I aim to (1) develop new theories to describe the trace element content of iron oxides and apatite using the new technique of laser ablation ICP-MS, (2) determine the geological processes that control and modify the trace element content of these minerals and (3) use trace element chemistry of ore minerals to enhance our understanding of oxide deposits from more complex geological settings, for example where genetic relationships between oxide mineralization and host rocks is unclear. This funding will support an early career scientist to build a new high-caliber research group and provide quality training of Highly Qualified Personnel in the fields of analytical geochemistry, igneous petrology and mineral deposits. ***Mineral chemistry provides important information on processes forming igneous rocks and their ore deposits, but it has been underexplored for trace elements due to limitations in analytical capabilities. However, it is now possible to determine, at the grain scale, a much larger number of trace elements than before using the technique of laser ablation ICP-MS. In order for this technique to become common practise it is critical to understand the processes that control the abundance of trace elements in minerals. My initial work on trace element chemistry of magnetite has demonstrated the potential of this technique for understanding, and tracking, processes involved in forming some magmatic mineral deposits. It is expected that this pioneering research program on oxide deposits will provide additional constraints on i) when and how the ore minerals formed, (ii) how they became concentrated into mineralized layers/lenses and (iii) tectonic setting of oxide deposits and their intrusions. This research will also have impact and significance on a broad range of disciplines because the chemistry of detrital grains of iron oxides and apatite can be used to `fingerprint' different rock types and thus indicate the provenance of sedimentary rocks and surficial sediments. The latter is of great interest to the Canadian economy for the exploration of new mineral resources.