Tracing differentiation processes through siderophile elements, from meteorites to giant ore deposits

The siderophile (iron-loving) elements represent a group of transition metals which largely partitioned into the Earth’s core during planetary differentiation. Because siderophile elements are typically depleted in the crust and mantle by several orders of magnitude relative to their solar abundances, they are also known as precious metals. Mineable deposits of these metals usually result from the erosion of (ultra)mafic rocks that may sample distinct mantle domains.
The DESIRED project aims to trace the source and study the distribution of (partially) siderophile elements (including gold [Au] and the platinum group elements [PGE]) in terrestrial rocks and meteorites to better constrain planetary differentiation processes and the formation of (giant) ore deposits. By combining siderophile element abundances (Cr, Co, Ni, Mo, PGE, W, Re, Au) and isotope ratios (Cr, Ni, Mo, Ru, Os, W), we wish to (1) determine the origin of the world-class Au and PGE deposits in the Kaapvaal Craton (South Africa) by studying a selection of mafic magmatic rocks (and related shales) with ages spanning from ~3.5 to ~2 Ga, (2) characterize a small number of rare meteorites to test what specific information is carried by the applied isotopic proxies, and (3) study rare Ni enrichments in Devonian limestone deposits from Belgium to assess whether isotopic signatures linked to meteorite bombardments can be preserved over time. By integrating these objectives, we aim to better constrain the processes leading to siderophile element enrichments and link mantle heterogeneity to early differentiation processes or late accretion.