Convergent margin metallogenic cycling in the Eastern Goldfields Superterrane and Tasman Element

Over 900 Australian mineral deposits, location and age data, combined with deposit classifications, have been used to assess temporal and spatial patterns of mineral deposits associated with convergent margins and allow assessment of the potential of poorly exposed or undercover mineral provinces and identification of prospective tracts within known mineral provinces. Here we present results of this analysis for the Eastern Goldfields Superterrane and the Tasman Element, which illustrate end-members of the spectrum of convergent margin metallogenic provinces. Combining our Australian synthesis with global data suggest that after ~3000 Ma these provinces are characterised by a reasonably consistent temporal pattern of deposit formation, termed the convergent margin metallogenic cycle (CMMC): volcanic-hosted massive sulfide – calc-alkalic porphyry copper – komatiite-associated nickel sulfide → orogenic gold → alkalic porphyry copper – granite-related rare metal (Sn, W and Mo) – pegmatite. Between ca 3000 Ma and ca 800 Ma, virtually all provinces are characterised by a single CMMC, but after ca 800 Ma, provinces mostly have multiple CMMCs. We interpret this change in metallogeny to reflect secular changes in tectonic style, with single-CMMC provinces associated with warm, shallow break-off subduction, and multiple-CMMC provinces associated with modern-style cold, deep break-off subduction. These temporal and spatial patterns can be used to infer potential for mineralisation outside well-established metallogenic tracts. <b>Citation:</b> Huston D. L., Doublier M. P., Eglington B., Pehrsson S., Mercier-Langevin P. & Piercey S., 2022. Convergent margin metallogenic cycling in the Eastern Goldfields Superterrane and Tasman Element. In: Czarnota, K. (ed.) Exploring for the Future: Extended Abstracts, Geoscience Australia, Canberra, https://dx.doi.org/10.26186/147037