South Australia
Under South Australia
Companies that drill for minerals in South Australia report their results to the State, and the Geological Survey of South Australia keeps them in one database, SA Geodata. Each year it releases a copy of the drillholes and their assays as open data.
That gives {holes} mineral drill holes you can see here, each one a place where somebody went looking for metal. This tour flies you through the places and stories behind them, then hands you the controls.
1880 to today
A century and a half of looking
Watch the holes arrive year by year. Only about 6,000 of them are dated before 1960. Then the numbers climb: {d1990} holes in the 1990s, {d2000} in the 2000s and {d2010} in the 2010s.
About three in four holes here were drilled before 2010, by companies that have mostly moved on, merged or closed. The 2020s look quiet ({d2020} so far) because new results take years to reach the open database. Another {d0} holes have no usable date.
1842 to 1877
The copper colony
South Australia was a young and nearly broke colony when copper turned up. Francis Dutton and Charles Bagot found ore at Kapunda in 1842, and mining began there in 1844. In June 1845 a shepherd, William Streair, brought rich copper ore from Burra to Adelaide. Burra soon became known as the Monster Mine and produced about 50,000 tonnes of copper before it closed in 1877.
Burra reopened as an open cut in 1971 for about a decade. Kanmantoo, in the Adelaide Hills, was first mined from 1846. The holes below Burra were drilled long after the old miners left. {site}
1859 to 1923
Moonta, Wallaroo and the Cornish miners
Copper was found on northern Yorke Peninsula near Kadina in 1859, and in 1861 a shepherd, Patrick Ryan, found it at Moonta. Large numbers of Cornish miners came to work the lodes, and the area became known as Little Cornwall. The main Moonta mines stopped in 1923.
The Cornish mining sites at Burra and Moonta were added to the National Heritage List in 2017. Later explorers came back to test the old field with modern drilling. {site}
Gold
Gold on the Gawler Craton
Colour the holes by gold and the old heart of the State lights up. The Gawler Craton is a block of very old rock covering much of the west, mostly hidden under sand and calcrete. {Au} of the holes here were assayed for gold. Each column's height is the number of holes in it, and its colour is a high but typical gold grade there.
Gold was found at Tarcoola in 1893. The big rush came in the 1990s, after the Challenger find in 1995 and Tunkillia in 1996: about 30,000 holes from that decade were assayed for gold, more than eight times as many as in the 1980s.
1995
Challenger: gold under the calcrete
Dominion Mining found Challenger in early 1995 by sampling calcrete, the hard white crust that covers much of the outback, and drilling where it held traces of gold. Mining began in 2002 as an open pit and moved underground in 2005. The mine is now in care and maintenance.
This is the most densely drilled patch in the State's open data. {site}
1975
Olympic Dam: the hole that changed the State
Western Mining Corporation geologists reasoned that copper might sit where magnetic and gravity highs lined up deep under the Stuart Shelf. In July 1975 they drilled hole RD1 near Roxby Downs station. Copper minerals were noticed in its core in September 1975, and in 1976 hole RD10 cut 170 metres at 2.12 per cent copper.
Olympic Dam opened in 1988 and is now run by BHP. It produces copper, uranium, gold and silver. Most of its drilling is not in the open data, so fewer than a hundred deep holes show here. {site}
Copper
The copper belt on the craton's edge
Olympic Dam showed explorers what to look for: iron oxide copper gold deposits, formed about 1,590 million years ago, when granites and volcanoes heated the eastern edge of the Gawler Craton. Switch to copper and you can follow that belt from Prominent Hill in the north to Carrapateena and down to Yorke Peninsula.
{Cu} holes were assayed for copper, spread over the Curnamona Province in the east, the Flinders Ranges, the Gawler Craton and Yorke Peninsula. On Yorke Peninsula, around the old Moonta and Wallaroo mines and Hillside, a quarter of the holes reached 0.1 per cent copper.
2001
Prominent Hill
In 2001 the Adelaide explorer Minotaur Exploration drilled into copper and gold at Prominent Hill, south-east of Coober Pedy, under cover with nothing showing at the surface. Oxiana bought Minotaur in 2005, and the mine opened in February 2009. BHP took it over with OZ Minerals in 2023.
The holes below were drilled by Minotaur, Oxiana and earlier explorers. {site}
2005
Carrapateena
Explorer Rudie Gomez found Carrapateena in 2005, about 160 kilometres north of Port Augusta. Like Olympic Dam, the ore lies deep under younger rocks and was found by drilling a geophysical anomaly. OZ Minerals bought the project in 2011, and the first copper concentrate came out in December 2019.
Most holes here are deep diamond holes drilled to outline the ore body. {site}
2008
Hillside and the hunt for the next copper mine
In 2008 Rex Minerals drilled a gravity high on Yorke Peninsula, about 12 kilometres south of Ardrossan, and found copper, gold and iron in rocks like those at Olympic Dam. The search for copper kept going through the 2010s: about 21,000 holes from that decade were assayed for copper, about as many as in the 2000s.
Rex drilled more than 850 holes within 3 kilometres of Hillside between 2006 and 2013. {site}
Uranium
Uranium in the sands of Lake Frome
East of the northern Flinders Ranges, uranium sits in old river sands about 100 to 150 metres down. Beverley was found in 1969 and opened in 2001 as Australia's first in-situ recovery mine, where solutions pumped through wells dissolve the uranium. Four Mile, a few kilometres away, was found in 2005 and began production in 2014.
{U} holes in the State were assayed for uranium, four in five of them since 2000. Uranium explorers often measure grade with gamma probes lowered down the hole, and those probe readings are left out of this map. {site}
Curnamona
Kalkaroo and the far east
Near the New South Wales border, the Curnamona Province is the same old crust that holds Broken Hill. Kalkaroo, found in 1992, is a large copper-gold deposit close to the surface that Havilah Resources has drilled since the late 1990s. Nearby are the Portia and White Dam gold mines and the Mutooroo copper-cobalt deposit, first worked in the 1880s.
The holes below are mostly shallow reverse circulation holes, coloured by copper. {site}
1899
Iron Knob and the Middleback Range
BHP pegged the first claim at Iron Knob in 1897 and began mining in 1900, first as flux for its lead smelter at Port Pirie. A tramway to Hummock Hill, later Whyalla, followed in 1901. Iron Knob and Iron Monarch were quarried until 1998, and Iron Monarch was reopened in 2012.
To the south lie Iron Baron, Iron Duke and the other deposits of the Middleback Range, which have supplied the Whyalla steelworks. The holes below are coloured by iron. {site}
2004 to today
Drilling with the State's help
In April 2004 the State launched PACE, the Plan for Accelerating Exploration. Its drilling collaborations shared the cost of new holes with explorers: from 2004 to 2009, 168 successful proposals shared $10 million. Later rounds such as PACE Copper and PACE Minerals kept the idea going, and the database flags about 6,500 PACE drill holes.
Since 2016 the Federal Government's Exploring for the Future program has added new geoscience data, and in 2020 it was extended to the whole country. Most of the holes on this map still come from companies that drilled before these programs began.
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 only basic unit checks, and most holes were drilled by earlier holders of the ground. 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.
