Neighbouring orogenic gold deposits may be the products of unrelated mineralizing events

Gold metallogeny of the northern Capricorn Orogen

“…Monazite intergrown with ore-stage alteration minerals and euhedral xenotime crystals interlocking with auriferous pyrite provides an age for primary gold mineralization at c. 2400 Ma (Fielding et al, 2017a). This age is synchronous with a Pilbarawide cryptic orogenic event where widespread hydrothermal activity is recorded by the growth of hydrothermal monazite throughout the western Pilbara (Rasmussen et al 2005), hydrothermal xenotime growth at the nearby Belvedere prospect (Fielding et al, 2018), resetting of high-U zircons in the Hamersley Group (Pickard 2002), as well as extensive uplift and erosion of the southern Pilbara region (Takehara et al, 2010). The second mineralization event at Paulsens is recorded by the brecciation of former c. 2400 Ma-aged pyrite accompanied by new xenotime growth and deposition of gold along fractures and grain boundaries at c. 1680 Ma (Fielding et al, 2017a).…”

“…Gold deposits in the northern Capricorn Orogen are intimately associated with the major crustal-scale structures identified in the seismic reflection survey (Johnson et al, 2013). In particular, the Nanjilgardy and Baring Downs Faults appear to be the most important as they both extend to the mantle and show a close association with gold mineralization ( Figure. 1 and 2; Fielding et al, 2017a, 2018, 2019, under review, Johnson et al, 2013. The largest gold deposits are associated with the Nanjilgardy Fault, and include orogenic gold mineralization at the Paulsens deposit, and Carlin-like gold mineralization at the Mount Olympus deposit, both with endowments of >1 Moz (Fielding et al, 2017a(Fielding et al, , 2019.…”

“…The largest gold deposits are associated with the Nanjilgardy Fault, and include orogenic gold mineralization at the Paulsens deposit, and Carlin-like gold mineralization at the Mount Olympus deposit, both with endowments of >1 Moz (Fielding et al, 2017a(Fielding et al, , 2019. Numerous smaller orogenic gold deposits occur throughout the Ashburton Basin and Wyloo Inlier ( Figure 1; Seymour 1991, Thorne andTrendall 2001) and include the Belvedere (Fielding et al, 2018) and Star of the West gold deposits (Fielding et al, under review). These deposits have formed parallel to the youngest regional fabric and are interpreted to have occurred during hydrothermal activity associated with the Mangaroon Orogeny.…”

“…Şener et al, 2005). Finally, the c. 1680 Ma event represents widespread hydrothermal activity and gold mineralization throughout the northern Capricorn Orogen and the southern Pilbara region associated with the early stages of the intracratonic 1680-1620 Ma Mangaroon Orogeny (Fielding et al, 2017a(Fielding et al, , 2018.…”

“…Belvedere is an orogenic, vein-hosted gold deposit located in the Wyloo Inlier approximately 6.5 km to the southeast of the Paulsens deposit adjacent to the Hardey Fault (Fielding et al, 2018). Mineralized quartz-carbonate-arsenopyrite veins occur in the c. 2082 Ma Belvedere dolerite (Fielding et al, 2018) which intrudes vesicular basalt, polymictic conglomerate, sandstone and siltstone of the c. 2775 Ma Mount Roe Basalt (Thorne and Trendall 2001).…”