Offshore Mineral Resources
Australia has jurisdiction over a wide variety of offshore mineral deposits within its continental shelf and 200 nautical mile economic exclusion zone. These deposits include:
- Heavy mineral sands (containing zircon, rutile and ilmenite)
- Alluvium containing diamonds, topaz, tin and gold
- Manganese nodules and crusts
- Phosphorite deposits
- Shell limestone
- Coal (black and brown coals)
Of these deposits, iron (Yampi Sound), and tungsten (King Island) have been mined under areas covered, or previously covered by the sea. Sand has been dredged from South Australia, New South Wales, and Queensland waters and used to replenish beaches or for building materials. In Western Australia, shell limestone has been dredged for the production of lime. The map of Australian Offshore Mineral Locations depicts the location of many known deposits and shows the position of Australia's Marine Jurisdictions and its remote offshore territories. Data on the deposits can be viewed on line using Geoscience Australia’s Australian Marine Spatial Information System (AMSIS) which contains many layers of information that provide context for the deposits.
The States and Northern Territory hold the respective mineral rights out to three nautical miles from the low tide mark around the continent while the Commonwealth territory extends from the three nautical mile boundary out to the Exclusive Economic Zone boundary and is administered in collaboration with the Designated Authority of the relevant State or Territory. More detail of the Commonwealth Offshore Minerals Act 1994 is provided in the Geoscience Australia Publication Australia’s Identified Mineral Resources. This publication and the Offshore Minerals Fact Sheet also provide additional information on the deposits and exploration activities.