Uranium Ore Deposits
(last updated 17 Jul 2010)Contents:
- Uranium Ore Deposits: Geology · Size and Grade · Recovery Cost · Known Resources
- Uranium in Phosphate Rock
- Uranium in Waste Materials
- Uranium in Oceans
- Uranium in the Interior of the Earth
- Uranium on the Moon
- References
Uranium Ore Deposits
Geology
The International Atomic Energy Agency assigns the uranium deposits according to their geological settings to 15 main categories of deposit types, arranged according to their approximate economic significance [IAEA2004]:
- Unconformity-related deposits
- Sandstone deposits
- Quartz-pebble conglomerate deposits
- Vein deposits
- Breccia complex deposits
- Intrusive deposits
- Phosphorite deposits
- Collapse breccia pipe deposits
- Volcanic deposits
- Surficial deposits
- Metasomatite deposits
- Metamorphic deposits
- Lignite
- Black shale deposits
- Other types of deposits
Surficial Uranium Deposits (Report of the Working Group on Uranium Geology), IAEA-TECDOC-322, 1985.
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, (17804 kB PDF 
).Geological Environments of Sandstone Type Uranium Deposits (Report of the Working Group on Uranium Geology), IAEA-TECDOC-328, 1985.
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(27281 kB PDF )Vein Type Uranium Deposits (Report of a Working Group on Uranium Geology), IAEA-TECDOC-361, 1986.
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(33984 kB PDF )Uranium Deposits in Proterozoic Quartz-pebble Conglomerates (Report of the Working Group on Uranium Geology), IAEA-TECDOC-427, 1987.
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(27668 kB PDF )Volcanogenic Uranium Deposits: Geology, Geochemical Processes, and Criteria for Resource Assessment, by J. Thomas Nash, USGS Open-File Report 2010-1001, U.S. Geological Survey 2010, 99 p.
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Inturgeo: the International Uranium Geology Information System (A World Atlas of Uranium Occurrences and Deposits), IAEA-TECDOC-471, 1988.
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(22757 kB PDF )Franz J. Dahlkamp: Uranium Ore Deposits, 460 p., Berlin Heidelberg 1993 [detailed description of the geology of uranium deposits]
World Distribution of Uranium Deposits (UDEPO), with Uranium Deposit Classification, 2009 Edition, IAEA-TECDOC-1629, 2009
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(2.25M PDF )Size and Grade
The International Atomic Energy Agency defines the following categories for uranium resources [IAEA2004]:
- Identified Resources (formerly Known Conventional Resources)
- Reasonable Assured Resources (RAR)
- Inferred Resources (formerly Estimated Additional Resources I (EAR-I))
- Undiscovered Resources
- Prognosticated Resources (formerly Estimated Additional Resources II (EAR-II))
- Speculative Resources (SR)
| Meaning | Losses taken into acount | |
| in-situ resources | uranium contained in ore deposit | none |
| recoverable in-situ resources | uranium contained in mineable ore | mining losses |
| recoverable quantities of uranium | uranium recoverable from mineable ore | mining and milling losses |
Various other categories are in use worldwide, for example:
Definitions by the Canadian Institute of Mining, Metallurgy and Petroleum and incorporated into National Instrument 43-101:
CIM DEFINITION STANDARDS - For Mineral Resources and Mineral Reserves
- A mineral resource is a concentration or occurrence of diamonds, natural solid inorganic material, or natural solid fossilized organic material in or on the Earth's crust in such form and quantity and of such a grade including base and precious metals, coal and industrial materials, or quality that it has reasonable prospects for economic extraction. The location, quantity, grade, geological characteristics and continuity of a mineral resource are known, estimated or interpreted from specific geological evidence and knowledge. Mineral resources are subdivided, in order of increasing geological confidence, into inferred, indicated and measured categories.
- An inferred mineral resource is that part of a mineral resource for which quantity and grade or quality can be estimated on the basis of geological evidence and limited sampling and reasonably assumed, but not verified, geological and grade continuity. The estimate is based on limited information and sampling gathered through appropriate techniques from locations such as outcrops, trenches, pits, workings and drill holes.
- An indicated mineral resource is that part of a mineral resource for which quantity, grade or quality, densities, shape and physical characteristics, can be estimated with a level of confidence sufficient to allow the appropriate application of technical and economic parameters, to support mine planning and evaluation of the economic viability of the deposit. The estimate is based on detailed and reliable exploration and testing information gathered through appropriate techniques from locations such as outcrops, trenches, pits, workings and drill holes that are spaced closely enough for geological and grade continuity to be reasonably assumed.
- A measured mineral resource is that part of a mineral resource for which quantity, grade or quality, densities, shape and physical characteristics are so well established that they can be estimated with confidence sufficient to allow the appropriate application of technical and economic parameters, to support production planning and evaluation of the economic viability of the deposit. The estimate is based on detailed and reliable exploration, sampling and testing information gathered through appropriate techniques from locations such as outcrops, trenches, pits, workings and drill holes that are spaced closely enough to confirm both geological and grade continuity.
- A mineral reserve is the economically mineable part of a measured or indicated mineral resource demonstrated by at least a preliminary feasibility study. This study must include adequate information on mining, processing, metallurgical, economic and other relevant factors that demonstrate, at the time of reporting, that economic extraction can be justified. A mineral reserve includes diluting materials and allowances for losses that may occur when the material is mined. Mineral reserves are subdivided in order of increasing confidence into probable mineral reserves and proven mineral reserves.
- A probable mineral reserve is the economically mineable part of an indicated and, in some circumstances, a measured mineral resource demonstrated by at least a preliminary feasibility study. This study must include adequate information on mining, processing, metallurgical, economic and other relevant factors that demonstrate, at the time of reporting, that economic extraction can be justified.
- A proven mineral reserve is the economically mineable part of a measured mineral resource demonstrated by at least a preliminary feasibility study. This study must include adequate information on mining, processing, metallurgical, economic and other relevant factors that demonstrate, at the time of reporting, that economic extraction can be justified.
An ore grade of 1% U3O8 is equivalent to 0.848% U.
(see also Unit Converter: Uranium concentration (wt.) · Uranium contents in ore)
1 million lbs U3O8 are equivalent to approx. 385 metric tonnes of U. (see also Unit Converter: Uranium weight)
Recovery Cost
The International Atomic Energy Agency uses the following cost categories for uranium resources [IAEA2004]:
- $40/kgU or less (= $15.38/lb U3O8 or less)
- $80/kgU or less (= $30.77/lb U3O8 or less)
- $130/kgU or less (= $50/lb U3O8 or less)
- $260/kgU or less (= $100/lb U3O8 or less)
Uranium Mine Feasibility Calculator
(see also Unit Converter: Uranium price · Uranium weight <-> cost)
Known Resources
| Resource Category | Cost Ranges | ||||
|---|---|---|---|---|---|
| < 40$/kgU | < 80$/kgU | < 130$/kgU | |||
| Reasonably Assured Resources (RAR) | 1,766,400 | 2,598,000 | 3,338,300 | ||
| Inferred Resources | 1,203,600 | 1,858,400 | 2,130,600 | ||
| TOTAL | 2,970,000 | 4,456,400 | 5,468,800 | ||
"t" stands for metric tonne.
Not all countries report separate figures for the two lowest cost categories.
The figures are adjusted to account for mining and milling losses.
World Uranium Resources: data and interactive map (Java required) · static map
World Atlas of Uranium Deposits (UDEPO)
(iNFCIS, IAEA)World Distribution of Uranium Deposits (UDEPO), with Uranium Deposit Classification, 2009 Edition, IAEA-TECDOC-1629, 2009
> Download Full text
(2.25M PDF )> Calculate lifespan of the world uranium resources with the Nuclear Fuel Supply Calculator
> See also: Uranium Mines · Uranium Market
Uranium in Phosphate Rock
The world average uranium content in phosphate rock is estimated at 50 - 200 ppm. World uranium resources in phosphate rock are estimated at approx. 9 million t U.
> See: Uranium Recovery from Phosphates
Uranium in Waste Materials
A variety of waste materials may contain elevated concentrations of uranium that might be recoverable in certain circumstances, for example gold and/or uranium mill tailings, coal ash, and other waste materials.> See current issues: Uranium recovery from waste materials
Uranium in Oceans
Sea water contains approximately 3 ppb of uranium (= 3 mg/t).
> See current proposals for uranium recovery from sea water: USA · Japan · India
Uranium in the Interior of the Earth
Biggest uranium deposit ever detected - though a little bit hard to come by
The observation of geo-neutrinos at the Borexino detector at the Laboratori Nazionali del Gran Sasso (Italy) proves that a significant fraction, if not the majority of the geothermal heat power of the Earth of 40 Tera-Watt (TW = 1012 W) is generated from the decay of uranium and thorium. (Max-Planck-Institut für Kernphysik, Mar. 15, 2010)If this geothermal power is solely attributed to the decay heat of uranium and its progeny, this would indicate an amount of 400 trillion (400 • 1012) tonnes of uranium in the interior of the Earth. This would be sufficient to meet the current world requirements of 69,110 t U (2007) for approx. 5.8 billion years.1 g Unat in secular equilibrium with its progeny (U-238 and U-235 series) produces approx. 600 GeV/s of decay power (550 GeV/s from alpha, 27 GeV/s from beta, and 23 GeV/s from gamma decay, see Uranium Decay Calculator).New geoneutrino measurements found that decay of uranium-238 and thorium-232 together contribute 20 +8.8/-8.6 TW to Earth's total heat flux of 44.2 ±1.0 TW, while the neutrinos emitted from the decay of potassium-40 are known to contribute 4 TW.
600 GeV/s is equivalent to 9.613 • 10-8 W, or roughly 0.1 microWatt, so 10 t of Unat are required to generate a power of 1 W (see Unit Converter).
The total heat flux from the Earth is 40 TW. If all of this were from decay of Unat and its progeny, then 400 Tt (= 400 • 1012 t) Unat would be required to generate this heat flux.
> Partial radiogenic heat model for Earth revealed by geoneutrino measurements
, by The KamLAND Collaboration, in: Nature Geoscience, Published online 17 July 2011This means that there would be "only" max. 200 trillion tonnes of uranium in the interior of the Earth.
Uranium on the Moon
Scientists find first conclusive signature for lunar uranium
Robert C. Reedy, a senior scientist at the Tucson-based Planetary Science Institute, is mapping the moon's surface elements using data gathered by an advanced gamma-ray spectrometer (GRS) that rode aboard the Japanese Kaguya spacecraft. The data promise to show chemical elements on the moon that have never been identified before, and Reedy and the Kaguya GRS team already have found uranium signatures in the data, an element not seen in previous moon-mapping efforts. (Planetary Science Institute June 26, 2009)New moon map shows uranium in short supply
A new map of uranium on the moon has revealed the lunar surface to be a poor source of the radioactive stuff, but it could help solve mysteries as to how the moon formed. This new moon uranium map dampens hopes of a nuclear power industry on the lunar surface, researchers said. Proponents of lunar bases and future lunar colonies have long pointed to many of the moons minerals, along with water, as being useful to support such efforts. "Forget things like uranium mines or nuclear reactors," said cosmochemist Robert Reedy, a member of the Kaguya science team and a senior scientist at the Tucson-based Planetary Science Institute. "The concentrations are very far from being of commercial levels." The new map was created using data from Japan's Kaguya spacecraft, which launched in 2007. The spacecraft found uranium on the moon, along with other radioactive elements, with its advanced gamma-ray spectrometer. The new moon uranium map clearly shows the element is not abundant on the moon. In moon rock, it appears in quantities less than in many Earth granites. The scientists detailed their findings online May 20 in the journal Geophysical Research Letters. (Space.com June 22, 2010)Yamashita, N., et al. (2010), Uranium on the Moon: Global distribution and U/Th ratio, Geophys. Res. Lett., 37, L10201, doi:10.1029/2010GL043061.
References
[IAEA2008] Uranium 2007 - Resources, Production and Demand, OECD Nuclear Energy Agency
and International Atomic Energy Agency , Paris 2004Source: WISE
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