Base metal deposits of the Northern Territory

Abstract

This Report describes the major base metal deposits of the Northern Territory. There are currently 826 base metal deposits or occurrences in the Northern Territory (NT), including the McArthur River Mine, one of the world's largest lead-zinc operations. Based on the history of discoveries, prospective geology and the relatively low level of exploration, there is potential for new discoveries of significant base metal mineralisation in the Northern Territory.

Base metal deposits in this Report are defined as deposits or occurrences containing copper (Cu), lead (Pb), zinc (Zn), nickel (Ni) and cobalt (Co) mineralisation or various combinations of the same (polymetallic), and often including precious metals; that is, gold (Au) and silver (Ag).

The Northern Territory Geological Survey (NTGS) Mineral Occurrence Database (MODAT) records all the known mineral occurrences of the NT. MODAT currently lists 3471 mineral occurrences of which 24% (826) are base metal occurrences

Base metals were first mined in 1875 from a copper discovery made in 1869 in the Rum Jungle area in the Pine Creek Orogen (PCO). Towards the end of the nineteenth century, lead-zinc-silver mineralisation was also discovered in the PCO at Mount Evelyn and several other localities. Since then, the total recorded production of major base metals in the NT to June 2024 is 1 976 605 tonnes (t) of copper, 1 400 552 t of lead and 5 712 347 t of zinc. Nickel and cobalt have only been mined as byproducts from two operations, Home of Bullion and Whites.

Older Proterozoic geological units host the majority of the base metal occurrences. The PCO, McArthur Basin, and the Aileron and Warumpi provinces host most of these with most of the base metal production coming from the PCO and McArthur Basin deposits.

Historically, base metal exploration has been mainly focused in the PCO and McArthur Basin. Lesser exploration effort has been made in the greenfield areas, such as the Amadeus Basin and the Aileron, Warumpi and Irindina provinces. However, modern exploration techniques, such as helicopter or drone electromagnetic surveys, have led to the discovery of significant base metal mineralisation in newly explored areas, eg Cu-Au-Bi mineralised ironstone deposits in the Tennant Creek mineral field. Future base metal discoveries, both in historically worked and greenfield areas, will be a function of ongoing exploration activity combined with advanced exploration techniques.