Northern Territory Government Creating Opportunities for Resource Exploration

Zinc-lead-silver

The Northern Territory contains a variety of zinc-lead-silver mineral deposits that have produced over 3.2 Mt of zinc, 0.94 Mt of lead and ~30 million ounces of silver. The majority of production has come of the world-class McArthur River mine, which is currently the only mine for these commodities in the Northern Territory.

The McArthur River mine is situated about 70 km southwest of Borroloola, in the McArthur Basin. It is operated by McArthur River Mining Pty Ltd (MRM), a subsidiary of Glencore PLC. It opened as an underground mine in 1995 and has since converted to open cut. In 2014, production from McArthur River totalled 224,000t of zinc, 46,200t of lead and 1.46 million ounces of silver. The McArthur River mine has a total resource of 202.3 Mt @ 10% Zn, 4.06% Pb, 46 g/t Ag. The deposit is regarded as a sedimentary exhalative (SEDEX) deposit, comprising fine-grained thinly bedded sulfide ore hosted in the HYC Pyritic Shale Member of the Barney Creek Formation. Another large SEDEX style zinc deposit was discovered in 2013 at Teena, 10 km west of McArthur River, by a Teck Australia-Rox Resources joint venture. Teena is a very similar style of high-grade mineralisation to McArthur River, with drill intersections including 38.8m @ 16.9% Zn+Pb. The Birrindudu Basin and Lawn Hill Platform also have high potential for shale-hosted zinc-lead deposits.

A number of base metal deposits occur in the Rum Jungle Mineral Field of the Pine Creek Orogen, including the polymetallic Browns deposit and the Woodcutters Pb-Zn-Ag deposit. Woodcutters is a vein-style deposit hosted by carbonaceous shales and was mined from 1984-99, producing 4.65 Mt ore averaging 12.28% Zn, 5.65% Pb and 87 g/t Ag. Polymetallic VMS-style deosits also occur at Iron Blow and Mount Bonnie north of Pine Creek.

Other provinces with high potential for zinc-lead-silver deposits are the Arunta Region, where the Jervois deposit has a resource containing 22.5 million ounces of silver and 143,000t of lead associated with a large copper resource, and the Warrumunga Province, where a zinc-lead resource has been defined at the Explorer 108 deposit in the Rover field. Neoproterozoic to Palaeozoic basins such as the Amadeus, Georgina, Daly and Bonaparte basins have potential for Mississippi Valley-style and other carbonate-hosted deposits.

Last updated: 29 Sep 2017