El Sherana is an abandoned

uranium Uranium is a chemical element with the symbol U and atomic number 92. It is a silvery-grey metal in the actinide series of the periodic table. A uranium atom has 92 protons and 92 electrons, of which 6 are valence electrons. Uranium is weak ...

mine in the South Alligator River Valley of the

Northern Territory The Northern Territory (commonly abbreviated as NT; formally the Northern Territory of Australia) is an states and territories of Australia, Australian territory in the central and central northern regions of Australia. The Northern Territory ...

Australia Australia, officially the Commonwealth of Australia, is a Sovereign state, sovereign country comprising the mainland of the Australia (continent), Australian continent, the island of Tasmania, and numerous List of islands of Australia, sma ...

. The deposit was discovered in 1954 by a United Uranium NL exploration team, led by Joe Fischer, with a ground radiometric survey. The site was named after the daughters of a team staff member, William 'Bluey' Halpin Kay - Elvira, Sherryl and Lana. El Sherana operated from 1958 to 1959 and El Sherana West from 1961 to 1964. El Sherana was the largest producer of high grade uranium ore (with minor gold and silver) amongst the mines along the South Alligator River Valley. It had underground and open-cut operations. Production from El Sherana was 38,437 long tons at a grade of 12.42 lb U₃O₈ per long ton (0.55% U₃O₈). From El Sherana West, 21,316 long tons at a grade of 18.35 lb U₃O₈ per long ton (0.82% U₃O₈) were produced. At El Sherana and El Sherana West, uranium-gold mineralisation occurs in two general settings: at or near the shallow-dipping Koolpin Formation/Coronation Sandstone unconformity, where it is cut by normal and reverse faults (El Sherana pit). The host rocks are

chert Chert () is a hard, fine-grained sedimentary rock composed of microcrystalline or cryptocrystalline quartz, the mineral form of silicon dioxide (SiO2). Chert is characteristically of biological origin, but may also occur inorganically as a prec ...

-banded

siltstone Siltstone, also known as aleurolite, is a clastic sedimentary rock that is composed mostly of silt. It is a form of mudrock with a low clay mineral content, which can be distinguished from shale by its lack of fissility.Blatt ''et al.'' 1980, p ...

and carbonaceous shale adjacent to

sandstone Sandstone is a clastic sedimentary rock composed mainly of sand-sized (0.0625 to 2 mm) silicate grains. Sandstones comprise about 20–25% of all sedimentary rocks. Most sandstone is composed of quartz or feldspar (both silicates) ...

(Coronation Sandstone) and altered volcanics (Pul Pul Rhyolite), in irregular zones along the contacts between cherty ferruginous shale and carbonaceous shale (El Sherana West). The ore consisted of massive pods and disseminated veinlets of

pitchblende Uraninite, formerly pitchblende, is a radioactive, uranium-rich mineral and ore with a chemical composition that is largely UO2 but because of oxidation typically contains variable proportions of U3O8. Radioactive decay of the uranium causes th ...

, with secondary

metatorbernite Metatorbernite (or meta-torbernite) is a radioactive phosphate mineral, and is a dehydration pseudomorph of torbernite. Chemically, it is a copper uranyl phosphate and usually occurs in the form of green platy deposits. It can form by direct depos ...

autunite Autunite (hydrated calcium uranyl phosphate), with formula Ca(UO2)2(PO4)2·10–12H2O, is a yellow-greenish fluorescent phosphate mineral with a hardness of 2–. Autunite crystallizes in the orthorhombic system and often occurs as tabular square ...

, gummite and gold, with minor

pyrite The mineral pyrite (), or iron pyrite, also known as fool's gold, is an iron sulfide with the chemical formula Iron, FeSulfur, S2 (iron (II) disulfide). Pyrite is the most abundant sulfide mineral. Pyrite's metallic Luster (mineralogy), lust ...

galena Galena, also called lead glance, is the natural mineral form of lead(II) sulfide (PbS). It is the most important ore of lead and an important source of silver. Galena is one of the most abundant and widely distributed sulfide minerals. It cryst ...

and

chalcopyrite Chalcopyrite ( ) is a copper iron sulfide mineral and the most abundant copper ore mineral. It has the chemical formula CuFeS2 and crystallizes in the tetragonal system. It has a brassy to golden yellow color and a hardness of 3.5 to 4 on the Mo ...

. Gold occurred as veinlets within pitchblende or as separate zones of mineralisation. Gold distribution extends beyond the high grade pitchblende pods that in places contain visible gold and forms an envelope around the poddy high grade uranium mineralisation, with grades of up to 0.2 ounce per ton (5.5 g/tonne).

Political importance

El Sherana was included in the 1988 proposal of

BHP BHP Group Limited (formerly known as BHP Billiton) is an Australian multinational mining, metals, natural gas petroleum public company that is headquartered in Melbourne, Victoria, Australia. The Broken Hill Proprietary Company was founded ...

to mine at the nearby

Coronation Hill Coronation Hill is a sandstone outcrop within Kakadu National Park in the Northern Territory of Australia. The area had been briefly mined for uranium at El Sherana in the 1950s and in 1988 proposals for new mining of gold were made. When min ...

which also had been briefly mined for uranium in the 1950s. Opposed environmental campaigns came from many organisations including the

Kakadu Action Group Kakadu is the German word for cockatoo Kakadu may refer to: Places Australia * Kakadu National Park, a protected area * Kakadu Highway, a highway in the Northern Territory * Kakadu, Northern Territory, a locality Plants and animals Australia ...

founded by

Lindsay Mollison Lindsay Clifford Mollison is a retired Consultant Physician in Gastroenterology and Infectious Diseases. He was the founding member of the Kakadu Action Group (KAG) that led a campaign to prevent mining in the Coronation Hill area of the Norther ...

, part of the

Australian Conservation Foundation The Australian Conservation Foundation (ACF) is Australia's national environmental organisation, launched in 1965 in response to a proposal by the World Wide Fund for Nature for a more co-ordinated approach to sustainability. One high-profil ...

. After some years of community debate the proposal was vetoed in a Cabinet Meeting, despite internal disagreement, by then Prime Minister,

Bob Hawke Robert James Lee Hawke (9 December 1929 – 16 May 2019) was an Australian politician and union organiser who served as the 23rd prime minister of Australia from 1983 to 1991, holding office as the leader of the Australian Labor Party (A ...

, in May 1991. His actions in Cabinet that day were regarded by some as important in his ultimately being replaced later that year. The El Sherana site was rehabilitated between 1988 and 1992. The area was added to

Kakadu National Park Kakadu National Park is a protected area in the Northern Territory of Australia, southeast of Darwin. It is a World Heritage Site. Kakadu is also gazetted as a locality, covering the same area as the national park, with 313 people recorded liv ...

after the proposal was defeated.

References

External links

El Sherana Deposit Summary Report
{{Coord, 13.5094, S, 132.5209, E, display=title Uranium mines in the Northern Territory 1954 establishments in Australia 1964 disestablishments in Australia Kakadu National Park Bob Hawke Nature conservation in Australia

Political importance

References

Further reading

External links