Northern Territory
Under the Northern Territory
Explorers in the Northern Territory must report their drilling to the Territory Government. When a report's confidential period ends it becomes open file, and the Northern Territory Geological Survey keeps the collars and assays from those reports in one geochemical database.
That gives {holes} open-file drill holes you can see here, each one a place where somebody went looking for metal. Most of them were drilled by earlier explorers, often decades ago, and not by whoever holds the ground today. This tour flies you through the places and stories behind them, then hands you the controls.
1950s to today
Seventy years of looking
Watch the holes arrive year by year. Where the completion date was not recorded, the year is the year the company report was lodged. The early decades are thin, then the 1990s bring a flood: {d1990} holes, many of them shallow vacuum and RAB holes across the Tanami and the Tennant Creek field. The 2000s add {d2000} and the 2010s {d2010}.
The 2020s look quiet ({d2020} so far) because recent drilling is mostly still confidential or not yet loaded. Another {d0} holes have no usable date, so they only show when the year filter is open.
1870 to 1872
The Overland Telegraph and the Pine Creek rush
The Overland Telegraph Line from Adelaide to Darwin was finished in August 1872, linking Australia to the world by cable. Men digging holes for its poles found gold near Pine Creek in 1871, and the rush that followed brought the first big wave of miners to the Top End.
Pine Creek has been mined on and off ever since, most recently from open pits. Here are the open-file holes around the old field, coloured by gold. {site}
Gold
Where the gold drilling went
Colour the holes by gold. {Au} of the open-file holes were assayed for it, more than for any other element. Each column's height is the number of holes in it, and its colour is a high but typical gold grade there (9 in 10 of its holes are below it), so one lucky hole doesn't paint a whole district.
Three clusters stand out: the Pine Creek field south of Darwin, the Tennant Creek field in the middle of the Territory, and the Tanami desert out west near the border with Western Australia.
1932
Tennant Creek: the last gold rush
Gold was found at Tennant Creek in 1932, and the rush that followed is often called the last great gold rush in Australia. Jack Noble and the blind prospector Bill Weaber pegged Nobles Nob in the early 1930s. It became one of the richest gold mines for its size in the world.
Tennant Creek gold sits in small, rich ironstone bodies under flat country, so finding them took a lot of drilling. These are the open-file holes around Nobles Nob, Juno and Peko, coloured by gold. {site}
Copper and bismuth
The ironstones of the Tennant field
The same ironstones that hold gold also carry copper and bismuth. Peko and Warrego were worked for copper and gold for decades, and the field was drilled again and again by a long line of companies.
Switch to copper and the Tennant field fills with columns. Most of these holes are shallow vacuum and RAB holes used to sample the ground under the soil.
1949
Rum Jungle and the uranium rush
In 1949 the prospector Jack White found uranium at Rum Jungle, south of Darwin. With government rewards on offer for uranium finds, it became Australia's first big uranium mine, worked from 1954 to 1971 to supply the British and American atomic programmes.
The pits left behind became a long clean-up project. Nearby Browns was later drilled for lead, zinc, copper and cobalt. {site}
1955
McArthur River: Here's Your Chance
In 1955 geologists from Mount Isa Mines found zinc and lead near the McArthur River, south of Borroloola. The HYC deposit, short for Here's Your Chance, is one of the largest zinc and lead deposits in the world, but its ore is so fine grained that it took until 1995 to mine it.
Most of the open-file holes here were drilled by Mount Isa Mines. Teena, a few kilometres west, was found much later. {site}
1969 to 2021
Ranger, Jabiluka and Kakadu
Airborne surveys in the late 1960s found a cluster of uranium deposits east of Darwin, including Ranger, Jabiluka and Nabarlek. The Ranger Uranium Environmental Inquiry of 1975 to 1977 weighed mining against Aboriginal land rights and conservation, and Kakadu National Park was declared in 1979 around the Ranger lease.
Ranger produced uranium from 1981 until January 2021. Jabiluka was never mined, and in 2024 its lease was not renewed so that it could become part of Kakadu. Very little of the drilling on these leases is in the open file, so the map is sparse right where the famous deposits sit.
Arnhem Land
Nabarlek
Nabarlek, in western Arnhem Land, was found in 1970 and mined in a single short campaign in 1979. Its ore was stockpiled and milled over the following years, and the site has since been rehabilitated.
The ground around it has been drilled again since then by later explorers looking for more uranium. {site}
1900 to today
Gold in the Tanami
Allan Davidson's expedition found gold at The Granites and in the Tanami in 1900, and small rushes followed, but water and distance beat most of the miners. Modern mining at The Granites began in the 1980s, and in the early 1990s drilling at Dead Bullock Soak found Callie, now one of Australia's largest underground gold mines.
Callie is deep, so this is one of the few places in the Territory with holes more than two kilometres long. {site}
1988 to today
Mount Todd
The Batman gold deposit at Mount Todd, north of Katherine, was found in 1988. Pegasus Gold began production in 1993, but low gold prices and poor recoveries closed the mine in late 1997, leaving the Territory with the clean-up when the company failed.
Later explorers drilled the deposit again in the 2010s. {site}
1960s to today
Groote Eylandt and Gove
Two of the Territory's biggest mines sit on the coast of the Gulf of Carpentaria. On Groote Eylandt, BHP's geologists recognised a major manganese deposit in the early 1960s, and the first ore was shipped in 1966. Across the water at Gove, bauxite has been mined near Nhulunbuy since the early 1970s.
Both are shallow, flat-lying ores, so they are drilled on tight grids of short holes, which shows up as dense carpets of points. {site}
2000s to today
The critical minerals era
In the last two decades the search has widened to the metals used in batteries, magnets and steel alloys. Molyhil, northeast of Alice Springs, holds tungsten and molybdenum, and Mount Peake vanadium. Nolans Bore, found in 1995 during uranium exploration, is a rare earths deposit, though little of its drilling is in the open file yet.
Near Darwin the old Bynoe tin field became the Finniss lithium project, and phosphate was drilled out at Wonarah and Ammaroo on the Barkly. This is the tungsten at Molyhil. {site}
2020
Drilling for everyone: East Tennant
Most holes on this map were drilled by companies. In 2020 MinEx CRC drilled ten stratigraphic holes, about 4,000 metres in all, under the Barkly Tableland east of Tennant Creek for Geoscience Australia's Exploring for the Future programme.
The cores and data were released to everyone, to test whether the Tennant Creek copper and gold belt carries on under the cover. They are the scattered deep holes in this view.
Your turn
How to read this map
Each point is one open-file hole, coloured by the best assay in that hole for the element you pick. The assays are as companies reported them, with no quality checks, and most holes were drilled by earlier explorers, not by today's owners. The company shown is the holder of the title the hole was reported on. Treat it as history, not a resource.
Use Explore to pick an element, set a minimum grade, slide through the years, search for a company or place, and dive into 20 deposits in 3D.
