Carbonatites host the main REE deposits in the world, with bastnaesite being the main REE-bearing mineral of interest. However, the nature of the enrichment process, magmatic vs hydrothermal, is still debated. This study aims to experimentally determine the behaviour of REE elements during carbonatite crystallisation, and if bastnaesite can be directly crystallised from a carbonate melt. Crystallisation experiments have been done from 900 to 600°C at 1 kbar on a REE-rich calciocarbonatitic composition. Calcite (Ca,REE)CO3...

Ultramafic-hosted mineralized systems commonly form massive sulphides at the seafloor which are enriched in base (Cu, Zn, Ni), critical (Co) and precious (Au, Ag) metals. In present-day settings, the limited conditions of observation at the seafloor prevents a complete understanding of these hydrothermal systems, especially concerning deep hydrothermal processes. A way to unravel deep hydrothermal processes that occur in these systems is to focus on fossil analogues preserved on-land which noticeably well crop out in...

As technology evolves, so does the way Canadians make payments. The Bank of Canada is therefore interested in researching the potential need for a digital alternative to cash. In a 2020 speech, Deputy Governor Tim Lane highlighted two scenarios that could warrant the launch of a central bank digital currency: - a decline in the use of cash - a rise in the use of cryptocurrencies. The Bank conducts regular surveys to monitor trends in...

Efficient fluid flow and circulation are important for an economically viable geothermal reservoir. One type of underexplored reservoir for high-temperature geothermal exploitation is a crustal fault zone, where hot fluids from depths corresponding to the brittle-ductile transition are brought to the surface via crustal-scale, permeable fault zones. To better understand the evolving permeability of reservoir rock during deformation in the brittle regime—fault formation and sliding on the fault—we performed triaxial experiments on samples of well-characterised...

Apatite is a pivotal mineral in carbonate rocks, because it can incorporate all of the major magmatic volatile species (H, P, F, S, Cl), as well as REE and HFSE into its structure. To quantify the effects of fractional crystallization of apatite crystals on the (H, P, F, S, Cl) volatiles and metal budget in the residue melt, the partition coefficients of a broad range of elements (F, Cl, S, REE, HFSE, Co, Ni, Sr,...