Lead as a pathfinder for uranium mineralization

International Nuclear Information System (INIS)

Shouls, M.M.

1983-01-01

The theoretical aspects of the formation of radiogenic lead anomalies from uranium and thorium mineralization are discussed in the light of differing mobilities of the parent elements and the stable lead daughter. It is concluded that recognizable lead anomalies can persist in the weathered tops of ancient uranium deposits, and such anomalies can be identified from the stable lead isotope ratios. In addition, with mixed U-Th mineralization lead isotopic ratios may be identified after most of the uranium has been leached away. The theoretical models also include possible additions of entrained lead with the mineralization and its effects on the isotopic ratios. This reasoning was tested in the evaluation of a radiometric anomaly in northern Malawi where a discrepancy between the U and eU values suggested a uranium-depleted mixed U-Th deposit. However, the partly coincident lead anomaly did not fit the isotope models proposed in the first part of the paper, and they indicated an unexpectedly young age. The anomaly was therefore downgraded but the adequacy of the theory was not tested. (author)

Geophysical features of uranium mineralization in Wadi Bahiya area, southern Jordan

International Nuclear Information System (INIS)

Zhao Xigang; Liang Shanming; Deng Xiaowei; Li Shengxiang; Wang Jinping

2010-01-01

Based on comprehensive study of geologic survey, sample analysis and ground gamma spectral survey, it is concluded that the uranium mineralization in Wadi Bahiya area, southern Jordan occurs near surface and is mostly hosted in weathered gray-brown chalk marl of Muwaqqar Chalk Marl Formation of the Upper Cretaceous and Paleocene, and belongs to surficial calcrete-type which is related to modern oxidation. The ground gamma spectral survey shows that surface anomaly area is small and big gradient change of the anomalies. The trenches reveal that uranium content of the anomalies falls down from near-surface to the deep. The analytical results of the samples from the area correspond with the gamma spectral measurements, demonstrating that uranium mineralization is mainly located within the depth between 0.5 and 1.5 m. (authors)

Characterization of titanite generations from Gameleira-I deposit (U-anomaly 35) Lagoa Real Uranium Province (LRUP), Bahia state, Brazil

International Nuclear Information System (INIS)

Santos, Camila M. dos; Rios, Francisco Javier; Amorim, Lucas E.D.; Palmieri, Helena E.

2017-01-01

The Lagoa Real Uranium Province (LRUP) is located in northwest of Bahia state and is the major uranium deposit of Brazil. Titanite is a common accessory mineral in rocks of LRUP and usually is part of uranium ore assemblage. Thirty three polished thin sections of F10 drill-hole located in Gameleira I deposit (anomaly 35) were petrographically studied and used for mineral chemistry study. Petrographically, titanite can be differentiated according to texture between granular and prismatic. Granular titanite is generally associated with magmatic assemblage (alkali feldspar hypersolvus granite) and it is present in some albitites (barren magnetite albitite). Prismatic titanite is restricted to albitite (garnet and mineralized magnetite albitite) and is associated with metamorphic assemblage. Microprobe analyses shows a trend from granites to mineralized albitites and do not cluster titanite by its texture, but by its host rocks. On the other hand, trace elements can distinguish titanite generation according to texture. Granular titanite is characterized by some highest high field strength elements (HFSE) values, like Hf, Pb, Th, U and HREE+Y, and the lowest V content. Vanadium has positive correlation with Zr/Hf ratio and inverse with U. Vanadium versus U relationship is inverse to the previously found by literature in LRUP what indicates that titanite was submitted to complexes processes of uranium loss after its crystallization. In addition, hafnium loss can be related to precipitation of hydrothermal zircon as it is strongly partitioned to this mineral. (author)

Characterization of titanite generations from Gameleira-I deposit (U-anomaly 35) Lagoa Real Uranium Province (LRUP), Bahia state, Brazil

Energy Technology Data Exchange (ETDEWEB)

Santos, Camila M. dos; Rios, Francisco Javier; Amorim, Lucas E.D.; Palmieri, Helena E., E-mail: cms@cdtn.br [Centro de Desenvolvimento da Tecnologia Nuclear (CDTN/CNEN-MG), Belo Horizonte, MG (Brazil)

2017-11-01

The Lagoa Real Uranium Province (LRUP) is located in northwest of Bahia state and is the major uranium deposit of Brazil. Titanite is a common accessory mineral in rocks of LRUP and usually is part of uranium ore assemblage. Thirty three polished thin sections of F10 drill-hole located in Gameleira I deposit (anomaly 35) were petrographically studied and used for mineral chemistry study. Petrographically, titanite can be differentiated according to texture between granular and prismatic. Granular titanite is generally associated with magmatic assemblage (alkali feldspar hypersolvus granite) and it is present in some albitites (barren magnetite albitite). Prismatic titanite is restricted to albitite (garnet and mineralized magnetite albitite) and is associated with metamorphic assemblage. Microprobe analyses shows a trend from granites to mineralized albitites and do not cluster titanite by its texture, but by its host rocks. On the other hand, trace elements can distinguish titanite generation according to texture. Granular titanite is characterized by some highest high field strength elements (HFSE) values, like Hf, Pb, Th, U and HREE+Y, and the lowest V content. Vanadium has positive correlation with Zr/Hf ratio and inverse with U. Vanadium versus U relationship is inverse to the previously found by literature in LRUP what indicates that titanite was submitted to complexes processes of uranium loss after its crystallization. In addition, hafnium loss can be related to precipitation of hydrothermal zircon as it is strongly partitioned to this mineral. (author)

Link between ore bodies and biosphere concentrations of uranium

International Nuclear Information System (INIS)

Gordon, S.

1992-01-01

A literature review of uranium exploration studies was carried out to determine the size and concentration of uranium anomalies in the biosphere. Fourteen sites were studied and uranium data were obtained for rocks, water-borne sediments, surface waters, groundwaters, soils and plants. Detailed descriptions of the study areas and of their uranium anomalies are provided. No statistical analyses of the data of anomaly sizes was undertaken because of the variation in the scale of the studies and in the threshold values used and the small number of samples for each medium. The threshold values and the size of the anomaly were found to be dependent on the scale of the study and of the sampling density. Sediments and surface waters were found to have the largest uranium dispersion. Although there was a wide range in the anomaly sizes it was possible to assign typical values for each medium. Based on a typical source of 1 km 2 in the rock it was found that anomalies of similar size as the source are expected in soils and plants, anomalies twice as large are typical for sediments and surface waters and anomalies of smaller areas than the source are possible for groundwater. Some limitations to providing typical groundwater anomaly sizes are outlined. Typical maximum concentrations for the sites studied were greater than 1300 ppm for rock, 10 to 110 ppm for sediment, and 5 ppb for surface waters. No typical values were observed for groundwater, soils and plants. Susceptibility of the host rock to leaching and the presence of discharge zones were assessed for their role in biosphere anomalies

Hydrogeochemical exploration for uranium in parts of Bhiwani district, Haryana, India - a preliminary study

International Nuclear Information System (INIS)

Pande, Dheeraj; Verma, A.K.; Srinivasan, S.; Bangroo, P.N.; Manjeet Kumar; Singh, Diwakar

1998-01-01

Hydrogeochemical exploration was carried out in the soil covered areas with isolated outcrops of metaquartzites of middle-Proterozoic Alwar group (Delhi supergroup) in parts of Bhiwani district of Haryana for identifying suitable locales for uranium mineralisation and also for establishing the sub-surface extensions of outcropping mineralisation. The preliminary evaluation of hydrogeochemical data indicates that the ground waters have dominantly surface water characteristics and are modified to some extent by agricultural fertilisers. Three hydrogeochemical anomalous zones, one each of uranium, uranium-vanadium and vanadium have been identified in the area. Anomalous content of uranium in the uranium zone is most likely to be due to very high sulphate content which may be a result of either heavy application of fertilisers or presence of gypsum-like horizons. The uranium-vanadium zone lies in close proximity to surface radiometric anomalies identified in the area and show little effect of agricultural contamination. The vanadium zone exhibits the least agricultural contamination and is related to ground waters of deeper origin. The uranium-vanadium and vanadium zones are found to be significant from the point of view of uranium mineralisation. The close association of uranium and vanadium in the area and the proximity of the uranium-vanadium zone to the surface radiometric anomalies suggest that the surface anomalies may have deeper extensions. (author)

Uranium exploration in Bangladesh

International Nuclear Information System (INIS)

Faruquee, A.R.

1988-01-01

The sedimentary succession of Bangladesh has continental sandstones with lignite and organic matter which are favourable host rocks for sedimentary uranium. The shield areas around Bangladesh are considered good source areas for uranium. Encouraged by this idea, the Bangladesh Atomic Energy Commission (BAEC) started an exploration programme in 1976 with the assistance of the IAEA and the United Nations Development Programme. Preliminary reconnaissance radiometric surveys carried out in 1976-1977 in the Chittagong, Chittagong hill tract and Sylhet districts identified some anomalies with 3 to 5 times the background (XBG). This was followed by regional reconnaissance radiometric surveys which were carried out between 1977 and 1985 in some of the anticlines of the Chittagong and Sylhet districts, including an airborne (helicopter) survey over the Jaldi area. These surveys resulted in the discovery of more than 300 radiometric anomalies of 3 to 60 XBG. They occur in the medium to fine grained ferruginous sandstones of the Dupitila and Tipam Formations of Mio-Pliocene age. These anomalous beds show variation in slime and heavy mineral contents. Some samples collected from the anomalous beds contain uranium and thorium ranging from 20 to 100 ppm and 100 to 1000 ppm, respectively. Exploratory drilling to a depth of about 400 ft was carried out on a very limited scale in the northeastern part of the Sylhet district. Gamma logging of these holes indicated many subsurface anomalies (3 to 21 XBG) in the Dupitila Formation. These anomalies are linked to thin layers with restricted lateral extensions. Geochemical orientation studies and radon surveys were done in some selected areas of Sylhet to test their suitability for further surveys. 9 refs, 13 figs, 4 tabs

Uranium occurence in the Rio Cristalino area, South of Para

International Nuclear Information System (INIS)

Andrade, S.M. de; Ribeiro, E.; Camarco, P.E.N.; Puppin, C.; Santos Filho, J.L. dos.

1986-01-01

The Rio Cristalino area where occurs uranium mineralization is located in the Western part of the Santana do Araguaia Town, Para State. This area comprises 1.350 Km 2 , and was selected from the evolution of the 'Projeto Geofisico Brasil - Canada - PGBC'. According to the results obtained from this Project, 15 airbone anomalies were selected for ground check. In the anomalies AN-03 and H-09 were found the best uranium occurence. The host rocks consist of arkose and sandstone of Pre-Cambriam ages, which show a very low-grade of metamorphism. The primary mineralization occurs in arkose along the cataclastic foliation (N70 0 W / 65 0 NE). The secundary mineralization involves clay galls and fills fracture zones in sandstone of the anomaly H-09. The highest grade detected in a rock sample of the anomaly AN-03 was 6,1% U 3 O 8 , whereas in the trenches there are intervals of 6 m thickness with a grade of 0,59% U 3 O 8 . Based on some mineralization aspects and field data, the genetic conceptual model to the uranium mineralization is proposed. (author) [pt

Report about drilling works made in 13 Anomaly de Taylor and in the N- NE of its, around Fraile Muerto (Cerro Largo district): Uranium project

International Nuclear Information System (INIS)

Massa, J; Pirelli, H.

1983-01-01

The perforations were carried out to investigate in depth denominated anomaly 13 detected during the Taylor Mission (1975) and extended the punch area of study during you are suitable DINAMIGE-BRGM (Project the present report details the activities realised in the environs Fraile Muerto (Cerro Largo district) by the command team of perforations of the uranium project. Previously and contemporarily to the executed works, prospection became geophysical ground geochemistry geology and, works. (Uranium)

Use of helium in uranium exploration, Grants district

International Nuclear Information System (INIS)

DeVoto, R.H.; Mead, R.H.; Martin, J.P.; Bergquist, L.E.

1980-01-01

The continuous generation of inert helium gas from uranium and its daughter products provides a potentially useful means for remote detection of uranium deposits. The practicality of conducting helium surveys in the atmosphere, soil gas, and ground water to explore for buried uranium deposits has been tested in the Grants district and in the Powder River Basin of Wyoming. No detectable helium anomalies related to buried or surface uranium deposits were found in the atmosphere. However, reproducible helium-in-soil-gas anomalies were detected spatially related to uranium deposits buried from 50 to 800 ft deep. Diurnal and atmospheric effects can cause helium content variations (noise) in soil gas that are as great as the anomalies observed from instantaneous soil-gas samples. Cumulative soil-gas helium analyses, such as those obtained from collecting undisturbed soil samples and degassing them in the laboratory, may reveal anomalies from 5 to 100 percent above background. Ground water samples from the Grants district, New Mexico, and the Powder River Basin, Wyoming, have distinctly anomalous helium values spatially related to buried uranium deposits. In the southern Powder River Basin, helium values 20 to 200 percent above background occur 2 to 18 mile down the ground-water flow path from known uranium roll-front deposits. In the Grants district, helium contents 40 to 700 percent above background levels are present in ground waters from the host sandstone in the vicinity of uranium deposits and from aquifers up to 3,000 ft stratigraphically above the deep uranium deposits. The use of helium in soil and ground-water surveys, along with uranium and radon analyses of the same materials, is strongly recommended is expensive, deep, uranium-exploration programs such as those being conducted in the Grants district

Latest data shows long-term security of uranium supply

International Nuclear Information System (INIS)

2010-01-01

Full text: According to Uranium 2009: Resources, Production and Demand just published by the OECD Nuclear En ergy Agency (NEA) and the International Atomic Energy Agency (IAEA), uranium resources, production and demand are all on the rise. Exploration efforts have increased recently in line with the expected expansion of nuclear energy in the coming years. Total identified resources have grown but so too have costs of production. Worldwide exploration and mine development expenditures have more than doubled since the publication of the previous edition, Uranium 2007: Resources, Production and Demand. These expenditures have increased despite declining uranium market prices since mid- 2007. The uranium resources presented in this edition, reflecting the situation as of 1 January 2009, show that total identified resources amounted to 6 306 300 tU, an increase of about 15% compared to 2007, including those reported in the high-cost category (< USD 260/kgU or < USD 100/lbU O), reintroduced for the first time since the 1980s. This high-cost 3 8 category was used in the 2009 edition in response to the generally increased market prices for uranium in recent years, despite the decline since mid-2007, expectations of increasing demand as new nuclear power plants are being planned and built, and increased mining costs. Although total identified resources have increased overall, there has been a significant reduction in lower-cost resources owing to increased mining costs. At 2008 rates of consumption, total identified resources are sufficient for over 100 years of supply. The recognition by an increasing number of governments that nuclear power can produce competitively priced, baseload electricity that is essentially free of greenhouse gas emissions, coupled with the role that nuclear can play in enhancing security of energy supply, increases the prospects for growth in nuclear generating capacity, although the magnitude of that growth remains to be determined. According to

Global Uranium Supply Ensured for Long Term, New Report Shows

International Nuclear Information System (INIS)

2012-01-01

Full text: Uranium resources and production are on the rise with the security of uranium supply ensured for the long term, according to a new report by the OECD Nuclear Energy Agency (NEA) and the International Atomic Energy Agency (IAEA). Uranium 2011: Resources, Production and Demand, commonly referred to as the ''Red Book'', shows that total identified uranium resources have grown 12.5% since 2008. However, the costs of production have also increased, leading to reductions in lower cost category resources. These figures, which reflect the situation as of 1 January 2011, mean that total identified resources are sufficient for over 100 years of supply based on current requirements. Global uranium mine production increased by over 25% between 2008 and 2010 because of significantly increased production in Kazakhstan, currently the world's leading producer. The increased resource base has been achieved thanks to a 22% increase in uranium exploration and mine development expenditures between 2008 and 2010, which in 2010 totalled over $2 billion. Demand for uranium is expected to continue to rise for the foreseeable future. Although the Fukushima Daiichi nuclear accident has affected nuclear power projects and policies in some countries, nuclear power remains a key part of the global energy mix. Several governments have plans for new nuclear power plant construction, with the strongest expansion expected in China, India, the Republic of Korea and the Russian Federation. The speed and magnitude of growth in generating capacity elsewhere is still to be determined. By the year 2035, according to the joint NEA-IAEA Secretariat, world nuclear electricity generating capacity is projected to grow from 375 GWe net (at the end of 2010) to between 540 GWe net in the low demand case and 746 GWe net in the high demand case, increases of 44% and 99% respectively. Accordingly, world annual reactor-related uranium requirements are projected to rise from 63 875 tonnes of uranium metal

Fluid inclusions in minerals associated to uranium mineralization in Jazida do Engenho (anomaly 09), Lagoa Real uranium province - Bahia, Brazil; Inclusoes fluidas nos minerais associados a mineralizacao uranifera da Jazida do Engenho (Anomalia 09), provincia uranifera de Lagoa Real, BA

Energy Technology Data Exchange (ETDEWEB)

Souza, Aurelio da Silva de

2009-07-01

The Engenho deposit (anomaly 09) is south-eastern from Cachoeira Mine (anomaly 13), in the northern part of the Province. The uranium mineralization is associated to 'albitites' (over 70% of albite/oligoclase). Epidosites with uranium may also occur. The 'albitite' main minerals are pyroxene, gamet, albite/oligoclase feldspar, amphibole and biotite. Pyroxene, gamet, plagioclase, titanite and epidote are the minerals associated to the uranium mineralization. The fluids related to pyroxene, gamet and epidote are aqueous-saline, primary and with no carbonic phases and are constant, with small variations. They all present medium to high salinity (14 to 18wt% NaCl eq.), the higher values being related to pyroxene and the lower ones related to gamet and epidote. The fluids associated to albite/oligoclase, although aqua-saline and with no carbonic phases, show salinities much lower than in pyroxene, gamet and epidote, suggesting a intense dilution process indicating dilution toward the later minerals phases. The data suggest the pyroxene formation process occurring under a 3,5 kbar pressure condition which corresponds to approximately 10km depth. The dispersion on Th in albites, due probably to the overheating and non elastic increase in volume, precluded a reliable pressure calculation. The IF's microscopy m plagioclase gneiss (albitites host-rocks) suggests the probability of primary carbonic fluids associated to these minerals. The fluids with CO{sub 2} showed in the gneiss maybe also be present in the albitites, probably as late or intergranular fluids. This assumption is based on the fact that signs of carbonic gases were shown during crushing tests. These tendencies suggest the occurrence of two albitization phases in this Lagoa Real area: one associated to a fluid composed by H{sub 2}O + CO{sub 2} + salts (in the gneiss host) and another (in the albitite) formed by an aqueous-saline phase. The data indicate the Brasiliano event as a thermal

International Uranium Resources Evaluation Project (IUREP) national favourability studies: Bangladesh

International Nuclear Information System (INIS)

1978-01-01

With the exception of the exploration activities in relation with the Beach Sand Project along the eastern Bay of Bengal, no systematic exploration for uranium had been done before December 1976, when a radiometric survey was implemented by the IAEA. As a result of this survey high radioactivity up to 450 cps was detected in placer Tipam deposits, The background of the terrain made up by Tertiary sediments is 160 - 170 cps. An anomaly was found in Kalipur Chara area which coincides with concentration of heavy minerals derived from Tipam Sandstones. Another anomaly was found within a horizon of Tipam sandstone crossing Hari River. An isolated outcrop in the riverbed showed a count rate up to 4 times background. During the follow up work it was found that this steeply dipping mineralized band stretches (with interruptions) over a distance of at least 3km along a strike. Samples collected from three different spils showed concentration of uranium 50, 60 and 140 ppm. The mineralized bed varies in thickness from a few cm to 2 m. It consists of alternating altered and unaltered sandstone. Bangladesh and Australian experts have separated monazite, zircon, ilmenite, rutile and magnetite from local sands at Cox's Bazar, 96 km southeast of Dacca. Radioactive mineral content is around 3,1% and exploitation may be feasible. Concerning the present status of exploration the technical assistance mission of the IAEA in the field of uranium exploration in Bangladesh is continuing with the objective to evaluate uranium potential in Chittongong and Sylhet district. Concerning areas favourable for uranium first priority should be given to areas of Hari River and Kalipur Chara where radioactive anomalies were detected. In general the area covered by Tipam Sandstone appears to be favourable for uranium mineralization. The potential for new discoveries in Bangladesh appears to be not too bad. Speculative potential could be in the order of 1-10,000 tons uranium

On the peculiarities of subsurface uranium concentrations in the arid regions

International Nuclear Information System (INIS)

Kochenov, A.V.; Chernikov, A.A.

1976-01-01

The general features of uranium distribution in the zone of hypergenesis of the area under investigation suggest a lack of accumulations due to climatic or landscape factors alone and formed at the expense of background near-clark contents of uranium in primary rocks. The low uranium concentrations in the debris layer of weathered crusts of acidic effusive rocks and granites as well as in salt marshes are of areal distribution and, in practice, never recorded as anomalies. The processes of salt formation in the area discussed appear, in the absence of organic matter in the sediments, to be insufficient by themselves for the accumulation of uranium from its near-clark contents in the primary rocks. At the same time the arid conditions are undoubtedly favorable for the formation and persistence of accumulative diffusion aureoles emphasizing and revealing on the surface the smallest and poorest primary concentrations of uranium. It is inadmissible to extrapolate the results of a study of one area to the entire variety of geomorphological conditions of the arid zone. The data reported show that care should be taken in interpreting uranium anomalies in arid areas, by all means taking account of the geological structure of the particular anomalous area and the uranium resources of the primary rocks

Study on Kalimantan uranium province: The assessment on uranium mineralization of metamorphic and granitic rocks at Schwaner mountains

International Nuclear Information System (INIS)

Tjokrokardono, Soeprapto

2002-01-01

Uranium exploration activities done by CEA-BATAN had discovered uranium occurrences as the radiometric and uranium content anomalies at metamorphic and granite rocks of Schwaner Mountains, Kalimantan. A part of the occurrences on metamorphic rocks at Kalan basin has been evaluated and be developed onto follow-up step of prospecting by construction of some drilling holes and an exploration adit. In order to increase the national uranium resources, it is necessarily to extent the exploration activity to out side or nearby of Kalan basin. The goal of this assessment is to understand the uranium accumulation mechanism at Pinoh metamorphic rocks of Kalan Kalimantan and to delineate areas that uranium may exist. The assessment was based on the aspect of geology, anomaly of radioactivity and uranium contents, tectonics and alterations. Pinoh metamorphic rocks which is influenced by Sukadana granite intrusion are the high potential rocks for the uranium accumulation, because the intrusion contains a relatively high of U, Th, Cu, Zn, Nb, Mn, and W. The potential rock distributions are in between G. Ransa granite intrusion at the east and Kotabaru granite intrusions at the west. The mineralizations are categorized as vein type deposits of granitic association

Mapping of radiation anomalies using UAV mini-airborne gamma-ray spectrometry.

Science.gov (United States)

Šálek, Ondřej; Matolín, Milan; Gryc, Lubomír

2018-02-01

Localization of size-limited gamma-ray anomalies plays a fundamental role in uranium prospecting and environmental studies. Possibilities of a newly developed mini-airborne gamma-ray spectrometric equipment were tested on a uranium anomaly near the village of Třebsko, Czech Republic. The measurement equipment was based on a scintillation gamma-ray spectrometer specially developed for unmanned aerial vehicles (UAV) mounted on powerful hexacopter. The gamma-ray spectrometer has two 103 cm 3 BGO scintillation detectors of relatively high sensitivity. The tested anomaly, which is 80 m by 40 m in size, was investigated by ground gamma-ray spectrometric measurement in a detail rectangular measurement grid. Average uranium concentration is 25 mg/kg eU attaining 700 mg/kg eU locally. The mini-airborne measurement across the anomaly was carried out on three 100 m long parallel profiles at eight flight altitudes from 5 to 40 m above the ground. The resulting 1 s 1024 channel gamma-ray spectra, recorded in counts per second (cps), were processed to concentration units of K, U and Th, while total count (TC) was reported in cps. Increased gamma ray intensity of the anomaly was indicated by mini-airborne measurement at all profiles and altitudes, including the highest altitude of 40 m, at which the recorded intensity is close to the natural radiation background. The reported instrument is able to record data with comparable quality as standard airborne survey, due to relative sensitive detector, lower flight altitude and relatively low flight speed of 1 m/s. The presented experiment brings new experience with using unmanned semi-autonomous aerial vehicles and the latest mini-airborne radiometric instrument. The experiment has demonstrated the instrument's ability to localize size-limited uranium anomalies. Copyright © 2017 Elsevier Ltd. All rights reserved.

On the genesis of the uranium occurrence in the carboniferous sediments, wadi Intahahah area, southwest Libya

International Nuclear Information System (INIS)

Assaf, H.S.

1988-01-01

In the course of covering the southwestern part of Libya by a systematic airborne radiometric survey, a significant group of anomalies was detected in the carboniferous sediments. Ground verification of these anomalies disclosed the confinement of these anomalies to the limestone and sandstone beds of the Assedjefar Formation assigned to visean-namurian age. Uranium content as much as 1000 PPm was detected. The strong lithologic control of these uranium mineralizations together with the lack of evidences of hydrothermal activity implies an intrinsic source for the uranium. The uranium, most likely, was transported and introduced into the sediments, by geochemically active groundwater, during their deposition. Uranium, from this solution, could have been adsorbed onto organic matter or clay minerals

Particle Size Effects in Bio leaching of Uranium From Saghand Ore by Acidithiobacillus Ferroxidans (A.f.)

International Nuclear Information System (INIS)

Rashidi, A.; Roosta Azad, R.; Safdari, S. J.

2012-01-01

The effect of mineral particle size on the bio leaching of uranium from Saghand mine (anomaly 1 and 2) by acidophilic mesophile Acidithiobacillus ferroxidans was investigated in a shake flask. The findings are indicating that this strain is suitable for the uranium recovery from the mentioned ore. In the range of our studies the uranium recovery is faster in the case of d 80 =108 micron from anomaly 1, while, a comminution level of d 80 =160 micron was obtained as an appropriate size for the anomaly 2. The results showed that the particle size distribution of the mineral in this range did not considerably influence the microbial activity. Also, based on the results of bacterial oxidation, the negative effects and toxicity due to the presence of solid and solute components do not put a limit on the microbial activity, and at the tested parameters range, the grown microbial population is performing the desired process excellently.

Uranium mineralization in the central region of Cuba

International Nuclear Information System (INIS)

Valdez, M.G.; Olivera, J.; Fernandez, P.

1995-01-01

The present work shows different geological and geophysical index for uranium mineralization found at Loma Alta iron ore deposit, located in the central region of Cuba. In this deposit was carried out pull work of iron ore. The tunnels were radiometrically documented in the wall and the floor observing some anomalies of the gamma ray intensity (up to 1700 c.p.s.) associated with the poor iron ore. In those points were collected solid sample. The obtained results were very important (uranium concentrations values up to 3500 ppm)

Preliminary report on the geology and metallogenesis of uranium in Bolivia

International Nuclear Information System (INIS)

Pardo-Leyton, E.; Barron, E.

1984-01-01

The paper is a preliminary study of aspects of the geology and metallogenesis of uranium in Bolivia. It must be considered as a first study which will serve as a basis for possible future work of this type. Its purpose is to show the possible relationships of the uranium anomalies and prospects to the country's various mineralized belts and also to the Nazca tectonic plate and to lineaments and intrusive bodies. (author)

Analysis on metallogenetic conditions of sandstone-type uranium deposit in Minhe Basin

International Nuclear Information System (INIS)

Jiang Minzhong; Wang Huaiwu

2002-01-01

Little uranium prospecting has been performed so far in Minhe basin. However, at the marginal areas of the basin uranium mineralizations and lots of aero-radioactive anomalies have been found before, and the basin shows some prospecting potential. Based on the regional geological setting, by means of interpretation of high-precision aero-magnetic, aero-radiometric and Bouguer gravimetric data, and combined with hydrodynamic, lithofacies-palaeographic and paleo-climatic analyses, authors make a comprehensive evaluation of metallogenic conditions for sandstone-type uranium deposits, and propose metallogenically favourable areas in the basin

Uranium isotopic disequilibrium in ground water as an indicator of anomalies

International Nuclear Information System (INIS)

Osmond, J.K.; Cowart, J.B.; Ivanovich, M.

1983-01-01

Because of the unique elemental and isotopic properties of uranium, ground water surveys are a most appropriate approach to prospecting for surficial and secondary uranium deposits. Uranium4+ is generally immobile, but in oxidising and carbonate bearing waters U 6 + is mobile and conservative. Uranium 234 is the radiogenic daughter of 238 U. The intervening α-decay event causes recoil displacements and radioactive disequilibrium between the two isotopes in open systems such as surficial aquifers. Extreme variations in dissolved uranium composition of ground waters combined with significant variations in the ratio 234 U/ 238 U are indicative of the proximity and stage of evolution of secondary deposits. (author)

Gravity data processing and research in potential evaluation of uranium resource in China

International Nuclear Information System (INIS)

Liu Hu; Zhao Dan; Ke Dan; Li Bihong; Han Shaoyang

2012-01-01

Through data processing, anomaly extraction, geologic structure deduction from gravity in 39 uranium metallogenic zones and 29 prediction areas, the predicting factors such as tectonic units, faults, scope and depth of rocks, scope of basins and strata structure were provided for the evaluation of uranium resources potential. Gravity field features of uranium metallogenic environment were summarized for hydrothermal type uranium deposits (granite, volcanic and carbonate-siliceous-argillaceous type) as regional gravity transition from high to the low field or the region near the low field, and the key metallogenic factors as granite rocks and volcanic basins in the low gravity field. It was found that Large-scale sandstone type uranium mineralization basins are located in the high regional gravity field, provenance areas are in the low field, and the edge and inner uplift areas usually located in the high field of the residual gravity. Faults related to different type uranium mineralization occur as the gradient zones, boundaries, a string of bead anomalies and striped gravity anomalies in the gravity field. (authors)

The South Greenland regional uranium exploration programme

International Nuclear Information System (INIS)

Armour-Brown, A.; Tukiainen, T.; Nyegaard, P.; Wallin, B.

1984-02-01

This report describes the work and results of the last two field seasons (1080 and 1982) of the Syduran Project. The field work was concentrated in the Motzfeldt Centre and the Granite zone with a short reconnaissance of five uranium anomalies in the Migmatite Complex. The results from the Motzfeldt Centre show that it is composed of at least 6 syenite units which can be divided into two major phases of igneous activity. The radioactive mineralisation has been mapped by gamma-spectrometer and has proved to be very extensive. Uranium mineral occurrences found in the Granite Zone occur in the many faults and fractures, which dissect the area. A study of the fractures and fault movements in the zone makes it possible to suggest an overall structural framework in which to place the uranium occurrences in the zone. Field work on the Igaliko peninsula was confined to a small area known as Puissagtag where four pitchblende veins have been discovered. Numerous uraniferous showings, associated with fractures, have been located in the Vatnaverfi peninsula south of the Igaliko Fjord. Mineralogical studies have shown that 12 of these showings contain pitchblende, that 7 of them contain coffinite and that most of them contain brannerite. The most interesting find during the 1982 field season was in the Migmatite Complex. Five anomalously high uranium areas in the complex were explored briefly with the helicopter-borne scintillometer. Near a place called Igdlorssuit, where a particlarly high gamma-spectrometer anomaly was found during the reconnaissance gamma-spectrometer survey, a large raft of meta-sediments in rapakivi granite was found, in which radioactive mineralisation occurred. This proved to be due to fine disseminated uraninite which occurs over some 150 m of strike length with a width of 1-2 m. The results confirm that there is a good possibility of finding exploitable uranium mineral occurrences in South Greenland. (author)

Groundwater prospecting for sandstone-type uranium deposits: the merits of mineral-solution equilibria versus single element tracer methods. Volume II

Energy Technology Data Exchange (ETDEWEB)

Wanty, R.B.; Langmuir, D.; Chatham, J.R.

1981-08-01

This report presents the results of further research on the groundwater geochemistry of 96 well waters in two uraniferous aquifers in Texas and Wyoming, and is a continuation of the work presented by Chatham et al. (1981). In this study variations in concentrations of U, As, Mo, Se and V were compared with the saturation state of the groundwater with respect to mineral phases of these elements known or expected to occur in each area. The non-radiogenic trace elements exhibited strong redox dependence consistent with thermodynamic predictions, but their variations did not pinpoint existing uranium ore bodies, because of a shift in groundwater flow patterns since the time of ore emplacement. Saturation levels of trace element minerals such as realgar, native Se, and molybdenite showed broad anomalies around the ore-bearing areas, similar to patterns found for U minerals by Langmuir and Chatham (1980), and Chatham et al. (1981). The radiogenic elements Ra and Rn showed significant anomalies directly within the ore zones. Helium anomalies were displaced in the direction of groundwater flow, but by their magnitude and areal extent provided strong evidence for the existence of nearby uranium accumulations. Uranium isotope ratios showed no systematic variations within the two aquifers studied. Saturation maps for kaolinite, illite, montmorillonite and the zeolites analcime and clinoptilolite provided 1 to 2 km anomalies around the ore at the Texas site. Saturation values for the gangue minerals pyrite and calcite defined the redox interface and often suggested the position of probable uranium mineralization. When properly used, the groundwater geochemical concepts for exploration can accurately pinpoint uranium mineralization at a fraction of the cost of conventional methods that involve test drilling and geophysical and core logging.

Groundwater prospecting for sandstone-type uranium deposits: the merits of mineral-solution equilibria versus single element tracer methods. Volume II

International Nuclear Information System (INIS)

Wanty, R.B.; Langmuir, D.; Chatham, J.R.

1981-08-01

This report presents the results of further research on the groundwater geochemistry of 96 well waters in two uraniferous aquifers in Texas and Wyoming, and is a continuation of the work presented by Chatham et al. (1981). In this study variations in concentrations of U, As, Mo, Se and V were compared with the saturation state of the groundwater with respect to mineral phases of these elements known or expected to occur in each area. The non-radiogenic trace elements exhibited strong redox dependence consistent with thermodynamic predictions, but their variations did not pinpoint existing uranium ore bodies, because of a shift in groundwater flow patterns since the time of ore emplacement. Saturation levels of trace element minerals such as realgar, native Se, and molybdenite showed broad anomalies around the ore-bearing areas, similar to patterns found for U minerals by Langmuir and Chatham (1980), and Chatham et al. (1981). The radiogenic elements Ra and Rn showed significant anomalies directly within the ore zones. Helium anomalies were displaced in the direction of groundwater flow, but by their magnitude and areal extent provided strong evidence for the existence of nearby uranium accumulations. Uranium isotope ratios showed no systematic variations within the two aquifers studied. Saturation maps for kaolinite, illite, montmorillonite and the zeolites analcime and clinoptilolite provided 1 to 2 km anomalies around the ore at the Texas site. Saturation values for the gangue minerals pyrite and calcite defined the redox interface and often suggested the position of probable uranium mineralization. When properly used, the groundwater geochemical concepts for exploration can accurately pinpoint uranium mineralization at a fraction of the cost of conventional methods that involve test drilling and geophysical and core logging

Alpha spectrometry of thick sources. II. Application to the study of radioactive equilibria in uranium ores

International Nuclear Information System (INIS)

Acena Barrenechea, M.L.; Tormo Ferrero, M.J.

1977-01-01

A method for determining nuclide activities in 4n + 2 uranium series using alpha spectrometry of thick sources is described. This method has been applied to several uranium ores, showing different states of radioactive equilibria. The spectra from samples prepared by cold compression show some anomalies, due to the evolution and later decay of 219 Rn and daughters. This phenomenon must be taken in consideration when computing spectra line intensities. (author) [es

Uranium Content in the Geological Samples of Different River Valleys in the Dauki fault Belt of Jaintiapur

International Nuclear Information System (INIS)

Chowdhury, Minhaz ul Islam; Ahmed Monir; Bhuiyan Abu Daiyan; Akon Eunus

1996-01-01

Thirty four geological samples that include six radioactive rock samples, four soil samples, two ooze samples,twelve stream-sediment samples and ten water samples, collected during a field survey in Jaintiapur area of the Dauki fault belt, oriented to the study on probable mobility of uranium either as detritus or in aquatic solution through the region, have been investigated with fluorimeter so as to find out content of uranium in the samples. The investigation aims at determining geochemical significance on uranium occurrence prevailing in the area. In general, the content of uranium in the rock samples lies in average distribution of geochemical interest. However, 194 ppm of uranium content in the gross material of the rock sample, collected from Lalakhal anomaly that records 1500 cps in situ, bears geochemical significance. But, the anomaly being associated with a cross -bedding, the presence of uranium may be inferred as an accumulation in placer sediment transported from a nearby source, Despite absence of in situ radiometric anomalies in the overall geological formations other than the Tipam and the Dupitila Sandstone members as encountered in the traverse of Sari valley , the area, in general, appears to be potential for possible occurrence of uranium. The transported stream sediments ooze and surface run-off water, as collected from the Rangapani, the Sari and even the Nayagang show geochemically significant distribution of uranium. Laboratory analyses of soil samples refers to dispersion of U bearing materials in the soil along the major channels.Uranium content in the surface run-off water of the Sari, the Rangapani and the Nayagang that have originated from the uranium bearing Meghalayan hills strongly support previous inference on mobility of uranium in aquatic solution through the geological formations of the area for possible formation of secondary uranium deposits. Eventually, prevailing geological evidences advocate that the area may be brought

Radiological analysis of solids around the old uranium mine of Rosglas (Morbihan). CRIIRAD N.08-119 note

International Nuclear Information System (INIS)

2008-01-01

As uranium mines present significant radiological contaminations years after their exploitation, this document reports preliminary investigations performed around old uranium mines in Brittany. This preliminary work showed significant radiological anomalies, with gamma radiation fluxes between ten and twenty times higher than the natural level. Measurement procedures and results are presented. Sampling has been performed on surface soil, stones and waters. Sample processing is briefly described. Results are commented in terms of contamination by uranium 238 and 235

Uranium prospecting in the Iguatu and Frade basins (Brazil)

International Nuclear Information System (INIS)

Lemos, J.C.

The Mineral Exploration Department of CNEN studied the possibilities of uranium occurences in the Iguatu and Frade Basins in the preliminary research program designated 'Small Basins of the Northeast' which contitutes the object of this report. The two basins are located in the State of Ceara. The results of geologic and radiometric researches ahowed that the possibilities for uranium mineralizations were small, since the analyses of samples from the two main anomalies showed the radioactivity came from the remains of monazite. Further analysis of sedimentologic factors indicated favorable confitions for uranium concentration, taking into consideration the large variations of vertical and lateral granulometries, which permit spectulation about the flow of uraniferous solutions. radiometric measurements of surface samples were insignificant and no uranium mineral was found. The result of research of the sedimentary Frade Basin was negative for uranium mineralization. The basin was entirely eroded, remaining as an outcrop described in this report. (F.E.) [pt

Techniques Currently Used in Uranium Prospecting in Canada

Energy Technology Data Exchange (ETDEWEB)

Little, H. W.; Smith, A. Y. [Geological Survey of Canada, Ottawa, Ont. (Canada)

1969-03-15

The sequence of existing practice in the search for uranium deposits in Canada begins with the establishment of a factual classification of types of uranium deposits and the criteria for recognition of the geological environment favourable to each type. The next step is the careful appraisal of geological maps and reports to determine regions and, more specifically, rock formations in which these criteria exist. Guidelines in the selection of such areas were given in a recent Geological Survey paper by S M. Roscoe. In most areas, once a favourable region or formation is selected, initial field investigation is preceded by an airborne scintillometer or airborne gamma-ray spectrometer survey. Detailed geological mapping is usually done, particularly by the larger companies, with special attention to the cause of anomalies. The form of geological studies is dependent on the type of uranium deposit, in the Elliot Lake area sedimentological studies comprise the mam guidelines in the search for ore whereas structural interpretation is the keynote in such areas as Uranium City. Detailed scintillometer grid surveys on the ground are used subsequently to pinpoint the targets to be surface trenched or diamond drilled. The drilling pattern is also governed by the type of deposit. Down-hole scintillometer probes are used to extrapolate data obtained by more costly chemical assays. Research is being conducted, both by private industry and by the Geological Survey of Canada, into improved design and sensitivity of airborne gamma-ray spectrometry, and airborne magnetometers. The Geological Survey is testing AFMAG equipment, and plans to cover the Uranium City area, where pitchblende-bearing veins are in or close to faults. Geochemical research is being undertaken on the behaviour of uranium ions, in stream sediments, in soils, and in surface waters, relative to their use in prospecting for uranium deposits. Recent analyses for radon in surface waters has shown a closer

Extraction and analysis of reducing alteration information of oil-gas in Bashibulake uranium ore district based on ASTER remote sensing data

International Nuclear Information System (INIS)

Ye Fawang; Liu Dechang; Zhao Yingjun; Yang Xu

2008-01-01

Beginning with the analysis of the spectral characteristics of sandstone with reducing alteration of oil-gas in Bashibulake ore district, the extract technology of reducing alteration information based on ASTER data is presented. Several remote sensing anomaly zones of reducing alteration information similar with that in uranium deposit are interpreted in study area. On the basis of above study, these alteration anomaly information are further classified by using the advantage of ASTER data with multi-band in SWIR, the geological significance for alteration anomaly information is respectively discussed. As a result, alteration anomalies good for uranium prospecting are really selected, which provides some important information for uranium exploration in outland of Bashibulake uranium ore area. (authors)

Characteristics and its uranium metallogenic potential of the granite belt between Bange and Jiali county, tibet

International Nuclear Information System (INIS)

Zhao Baoguang; Wang Qin; Liu Zhipeng; Chen Yuliang; Xu Wei

2012-01-01

The granite belt between Bange and Jiali county is a composite batholith which intruded at multistage, it con- trolled by several groups of the fault system, the alteration is developed, with the alaskite, aplite, pegmatitic vein intruded, it is type Ⅰ in the beginning of forming, and change to type S in the late time. There is a large of geochemical anomalies of uranium (U>6.8 X 10 -6 ) in Gulu town and Sangba village, of which middle of the granite belt and Bianba county of which east of the granite belt, that anomalies area have 1200 km 2 , 800 km”2 and 1500 km 2 . All the anomalies is considered that its forming relate to batholith and its external contact, so it shows that it has favorite geological conditions for granite type uranium metallogenesis. (authors)

Depth study of insular shelf electric sounding Adelaida anomaly (Rivera)[Geochemical prospection of Uranium in Uruguay]; Estudio de la profundidad del zocalo por sondeos electricos Anomalia Adelaida (Rivera)

Energy Technology Data Exchange (ETDEWEB)

Cicalese, H

1983-07-01

In the framework of the Uranium prospecting programme, the DINAMIGE geophysical equipment have made a study. It was about the depth of insular shelf electric sounding on the anomalies zone of Adelaida. This equipment carried out a study of the following subjects: geographical location, geologic framework, geophysical intervention, developed works, methods and material and results.

Anomalies from aerial spectrometric and total count radiometric surveys in the southeastern United States

International Nuclear Information System (INIS)

Lee, C.H.; Lawton, D.E.

1978-01-01

Aerial radiometric reconnaissance surveys are conducted because of their cost, time, and manpower savings compared to surface studies. Two types of aerial surveys are being flown in the southeastern United States: total count gamma-ray surveys for the Coastal Plains Regional Commission and the US Geological Survey, and differential gamma-ray spectrometric surveys for the US Department of Energy. Anomalous radioactivity detected during aerial surveys is related to higher concentrations of naturally occurring uranium, or to cultural activities, natural causes, or mapping errors which simulate real uranium anomalies. Each anomaly should be ground checked; however, several types of anomalies may be eliminated by evaluation of the aerial data in the office if field time is limited

Integrated geophysical investigations for uranium : a case study from Jamiri, West Kameng district, Arunachal Pradesh

International Nuclear Information System (INIS)

Srinivas, R.; Dash, J.K.; Sethuram, S.; Tiku, K.L.; Behari, Bipan

1991-01-01

An integrated geophysical approach was attempted for uranium exploration in Jamiri area, Arunachal Pradesh, using the techniques of magnetic, self-potential (SP) and resistivity profiling, coupled with solid state nuclear track detection (SSNTD), to delineate favourable structures controlling uranium mineralisation in phyllitic quartzites and quartzites of the Precambrian Daling formation. Three promising zones of uranium mineralisation were recognised based on integrated results from these surveys. Magnetic survey identified lithologic contacts and faults in the area. A high-order SP anomaly of -900 millivolts was observed near the contact of phyllites in the east and phyllitic quartzites in the west. A very low resistivity of 1.0 ohm.m and high SSNTD values of 120 tracks/mm 2 over a background of 20 to 30 tracks/mm 2 were also recorded near this contact. These anomalies are characteristic of a fault that channelises radon and gives low resistivities. The SP anomaly may indicate sulphide mineralisation, and hence, uranium mineralisation in this contact zone may be associated with sulphides. The phyllitic quartzites west of this contact are characterised by magnetic highs ranging from 540 to 900 gammas. Here, SP anomalies are also small closures of -80 to -100 mV. The SSNTD values range between 100 and 120 tracks/mm 2 . This rock unit (phyllitic quartzite) appears to host uranium mineralisation along with sulphides at some places where radon anomalies are high. A fault in the western portion of the area interpreted from the magnetic map separates phyllitic quartzites in the east and quartzites to its west. The faulted contact is characterised by a high SP gradient and SSNTD anomalies of 100 to 140 tracks/mm 2 . This contact may also be promising for uranium mineralisation at depth. (author). 10 refs., 8 figs

National Uranium Resource Evaluation: Wichita Falls Quadrangle, Texas and Oklahoma

International Nuclear Information System (INIS)

Edwards, M.B.; Andersen, R.L.

1982-08-01

The uranium favorability of the Wichita Falls Quadrangle, Texas and Oklahoma, was determined by using National Uranium Resource Evaluation criteria; by subsurface studies of structure, facies distribution, and gamma-ray anomalies in well logs to a depth of 1500 m; and by surface studies involving extensive field sampling and radiometric surveying. These were supplemented by both aerial radiometric and hydrogeochemical and stream-sediment reconnaissance studies. Favorable environments were identified in fluviodeltaic to fan-delta sandstones in the upper Strawn, Canyon, and Cisco Groups (Pennsylvania to Lower Permian), which occur exclusively in the subsurface. Evaluation was based on the presence of a good uranium source, abundant feldspar, good hydrogeologic characteristics, association with carbonaceous shales, presence of coal and oil fields, and anomalies in gamma logs. Additional favorable environments include deltaic to alluvial sandstones in the Wichita-Albany Group (Lower Permian), which crops out widely and occurs in the shallow subsurface. Evaluation was based on high uranium values in stream-sediment samples, a small uranium occurrence located during the field survey, anomalous gamma logs, good uranium source, and hydrogeologic characteristics. Unfavorable environments include Cambrian to Permian limestones and shales. Pennsylvanian to Permian fluviodeltaic systems that have poor uranium sources, and Permian, Cretaceous, and Pleistocene formations that lack features characteristic of known uranium occurrences

A RE-INTRODUCTION TO ANOMALIES OF CRITICALITY

International Nuclear Information System (INIS)

Puigh, R.J.

2009-01-01

In 1974, a small innocuous document was submitted to the American Nuclear Society's Criticality Safety Division for publication that would have lasting impacts on this nuclear field The author was Duane Clayton, manager of the Battelle Pacific Northwest National Laboratory's Critical Mass Lab, the world's preeminent reactor critical experimenter with plutonium solutions. The document was entitled, 'Anomalies of Criticality'. 'Anomalies...' was a compilation of more than thirty separate and distinct examples of departures from what might be commonly expected in the field of nuclear criticality. Mr. Clayton's publication was the derivative of more than ten thousand experiments and countless analytical studies conducted world-wide on every conceivable reactor system imaginable: from fissile bearing solutions to solids, blocks to arrays of fuel rods, low-enriched uranium oxide systems to pure plutonium and highly enriched uranium systems. After publication, the document was commonly used within the nuclear fuel cycle and reactor community to train potential criticality/reactor analysts, experimenters and fuel handlers on important things for consideration when designing systems with critically 'safe' parameters in mind The purpose of this paper is to re-introduce 'Anomalies of Criticality' to the current Criticality Safety community and to add new 'anomalies' to the existing compendium. By so doing, it is the authors' hope that a new generation of nuclear workers and criticality engineers will benefit from its content and might continue to build upon this work in support of the nuclear renaissance that is about to occur

Strategy and perspective for uranium exploration in Egypt

International Nuclear Information System (INIS)

Hassan, M.A.; Salman, A.B.; Assaf, H.S.; Mahdy, M.M.

1995-01-01

Uranium exploration started in Egypt about three decades ago. This was performed by applying integrated airborne and ground radiometric prospecting. The latter was conducted upon selected areas having rather favorable geological criteria. These activities resulted in the discovery of great numbers of radiometric anomalies, with several uranium occurrences in various geologic environments in granitic and sedimentary rocks. Some of these uranium occurrences show good potential for developing into workable uranium deposits. Small-scale exploratory tunnelling and drilling works have been carried out at some of these occurrences. Leaching studies and pilot experiments were carried out on technological samples to evaluate ore's suitability for uranium extraction. However, no assured reserves of uranium have been reached yet. The demands for uranium to satisfy the near future Egyptian nuclear power generation necessitates some development in the national strategy for uranium exploration. This will be achieved through intense programmes for ground geophysics and drilling from surface and underground mining works, in addition to radon emanometry and logging of oil and gas wells. Moreover, non conventional procedures for uranium extraction such as heap-leaching may be followed to exploit small-scale uranium deposits. In this developed strategy, the present uranium occurrences are modellized and categorized following the IAEA classification. The characteristics of the present uranium occurrences will be utilized in prospecting new areas. Subsidiary resources in phosphorites, black sands and rare metal deposits could supply additional quantities of uranium, in addition to thorium and rare earth elements. (author). 34 refs, 4 figs, 1 tab

Relationship between the feature of gravity and magnetic fields and uranium mineralization in the south piedmont of Tianshan mountain

International Nuclear Information System (INIS)

Cui Huanmin; Luo Juecheng.

1988-01-01

The figures of Bouguer anomalies and vertical magnetic anomalies obtained at the scales of 1:1000 000, 1:500 000 and 1:100 000 were processed and the Moho depths were calculated. The feature of gravity and magnetic fields over uranium deposits was determined through interpreting cmprehensive data from uranium deposits No. 504 and No. 509 and potential areas of uranium mineralization were predicted

Reguibat calcrete uranium project, Mauritania: Beneficiation upgrades and rapid leaching. A new paradigm for “calcrete” uranium projects?

International Nuclear Information System (INIS)

Beeson, Bob; Clifford, Neil; Goodall, Will

2014-01-01

Future of the project: • Scoping Study completed in the next two weeks; • Moving into Feasibility Studies: – Measured and Indicated resources; – Detailed beneficiation testing; – Leach testing of uranium concentrates; – Water drilling; – Commence process for Exploitation Permit. • Decision to mine in 12-18 months subject to funding; • Target production early 2017; • Convert known anomalies to achieve a 100Mlb uranium resource

Studi Keberadaan Mineralisasi Uranium Di Daerah Biak Numfor, Provinsi Papua Barat

OpenAIRE

Suharji, Suharji; Subiantoro, Lilik; Syaeful, Heri; Widana, Kurnia Setiawan; Prabowo, Hery

2014-01-01

Penelitian ini dilakukan berdasarkan adanya temuan indikasi mineral radioaktif berupa anomali laju dosis radiasi bernilai relatif tinggi. Hipotesis yang mendasari keberadaan laju dosis radiasi tinggi adalah pengendapan uranium yang berasal dari batuan basal Formasi Auwea, pengkayaan uranium yang berasal dari batugamping pada tanah permukaan, dan pengendapan uranium yang berasal dari penggunaan pupuk pertanian. Penelitian yang dilakukan bertujuan untuk mendapatkan kesimpulan dari beber...

Isotopic anomalies in high Z elements: Uranium?

International Nuclear Information System (INIS)

Jovanovic, S.; Reed, G.W. Jr.; Essling, A.M.; Rauh, E.G.; Graczyk, D.G.

1989-03-01

Uranium in terrestrial volcanic ejecta from mantle-related sources has been analyzed mass spectrometrically. The objective was to seek supporting evidence for or refutation isotopic variations reported by Fried et al. (1985) for some such samples. The possibility that terrestrial U is not of constant isotopic composition is extraordinary. If true, mechanisms for creating the variation must be sought and the lack of homogenization within the earth addressed. Samples of 100 grams or more were processed in order to minimize reagent and environmental (laboratory) blank interference and to permit isolation of large amounts (several to tens of μg) of U for the mass spectrometer (MS) measurements, which utilizes aliquots of /approximately/1 μg. Aliquants from four volcanic samples gave data which indicate enrichments of 235 U ranging from 0.2% to 5.9% in the 235/238 ratio relative normal uranium ratios. These relative enrichments are consistent with, and in some cases, higher than the 0.18% enrichment reported by Fried et al. (1985) for two volcanic lava samples. However, we were not able to reproduce their results on the Kilauea lava for which they report 0.18% 235 U enrichment. The relative error in our MS ratios is 0.05% -- 0.07%. 1 tab

Application of subinterval area median contrast filtering method in the recognizing of geochemical anomalies

International Nuclear Information System (INIS)

Zhao Ningbo; Fu Jin; Zhang Chuan; Liu Huan

2012-01-01

Traditional geochemical processing method sometimes maybe loses some weak anomalies related to mineralization, the authors can avoid the influence of geology background and can solve the problem of recognizing weak anomalies in the low-background and high-background area with the subinterval area median contrast filtering method. In an area of Jiangxi Province, several new anomalies are identified by this method and uranium mineralized prospects are found among them. (authors)

Evaluation of selected geochemical anomalies in Colorado and the Southeastern US. Final report

International Nuclear Information System (INIS)

Carpenter, R.H.

1980-08-01

This study demonstrates the utility of HSSR geochemical data from stream sediment in exploration for uranium. In the southeastern US, four uraniferous occurrences and associated radiometric anomalies were identified in areas where uranium mineralization has not been previously reported. At two localities, assays of about .01% have been obtained from saprolite. There is some evidence which suggests that uranium may have been leached at these localities and that higher grades of U are likely at depth

Geochemical signatures of uranium deposits within stream sediment of humid intertropical environment example from Gabon Francevillien deposits

International Nuclear Information System (INIS)

Nganzi, C.

1983-01-01

In the frame of geochemical prospection of uranium ores, the method based on adsorption is used for interpreting anomalies in classical methods. This study shows the importance of adsorption from specific surface area determined by the B.E.T. method [fr

Radioactive and geological analysis of airborne gamma spectrometric data for locating favorable traps for uranium prospecting in the Syrian desert (Area-1), Syria

International Nuclear Information System (INIS)

Asfahani, J.; Al-Hent, R.; Aissa, M.

2012-01-01

Statistical analysis has been applied to the airborne spectrometric data for the Syrian desert (Area-1), Syria in order to characterize and isolate the anomalous uranium radioactive zones. Equivalent uranium eU values vary between a minimum of 0.01 and a maximum of 32.74 ppm. Uranium prospecting methodology recently proposed is successfully applied in order to explain the origin of the radioactive anomalies related to Area-1. The dominant geological conditions effectively contributing to the uranium radioactive anomalies in the study area have been determined through the analysis of five radioactive-geological profiles. Different favorable traps have been identified and localized for uranium prospecting. Those uranium traps merit further detailed exploration for determining their uranium potential with depth. - Highlights: ► Determine the radioactive characteristics of Area-1. ► Apply a uranium prospecting methodology for guiding uranium exploration activities in Area-1. ► Explain the origin of the radioactive anomalies in Area-1. ► Relate the structural and geological conditions with the anomalous radioactive occurrences.

Comparison of total and cold-extractable uranium in stream sediments of the southwestern Karoo supergroup, South Africa

International Nuclear Information System (INIS)

Jakob, W.R.O.; Smit, M.C.B.; Murphy, G.C.

1979-01-01

In order to evaluate the usefullness of cold-extractable uranium as a tool of uranium prospecting in stream sediments of the southwestern Karoo, South Africa, ten orientation studies were conducted near known mineralisation jointly by the Atomic Energy Board and the Geological Survey of South Africa. These indicate that the topography determines the nature of the dispersion. In areas of moderate to high relief the total uranium content of the stream sediment gives dispersion trains up to about 500 m from the mineralisation, and peak-to-background ratios of about 3. The use of cold-extractable uranium doubles the length of the dispersion, and peak-to-background ratios are greater than 10 and may be as high as 35. In areas of low relief, the total uranium content of the sediment gives low anomalies, with short dispersion downstream. Cold-extractable uranium gives anomalies 500-1 000 m from the mineralisation. This is interpreted to be due to the longer residence time of the clay minerals in the stream. In order to test the applicability of cold-extractable uranium on a regional scale, 720 samples were collected at a density of one sample per square kilometre. Statistical treatment of the data shows the U content of the stream sediments, to be log-normally distributed. For cold-extractable uranium, polymodal distributions, apparently representing background and anomalous samples, can be separated with a high rate of success, and meaningful threshold values can be assigned. This is not the case for the total uranium content of the stream sediments [af

The Streltsovskoye uranium district

International Nuclear Information System (INIS)

Ischukova, L.P.

1997-01-01

This paper describes the geology of the Streltsovskoye uranium district located in south-eastern Zabaikalie region, Chita Province, Siberia, Russia. This district hosts Russia's only currently active uranium production centre. The uranium ore was discovered from 1963 to 1967 by drilling below fluorite veins which had minor associated uranium mineralization and radioactive anomalies. The uranium occurs as large scale vein stockwork deposits of hydrothermal origin within a volcano-tectonic caldera formed by continental volcanism of Late Mesozoic age. Rocks occurring in the caldera include basalt and trachydacite, overlain by rhyolite, and with associated interbedded sediments. The ore bodies occur in steeply dipping faults, with the greatest concentrations located where faults along the margins of the caldera intersect steeply dipping, cross cutting, northeasterly and northwesterly striking faults. The Streltsovskoye caldera extends over an area of 150 km 2 and is underlain by a large batholith. The 19 identified uranium deposits occurred in structural features that cut through the caldera sequence and extend into the basement rocks. The caldera has a maximum thickness of 1400 metres. Details of several deposits are given, including descriptions of mineralization and associated alteration. (author). 10 figs

The sedimentology of uranium-bearing sandstones on the farm Riet Kuil 307, Beaufort West area

International Nuclear Information System (INIS)

Cole, D.I.

1980-10-01

The sedimentology of four sandstones was studied in outcrop and in the subsurface on the farm Riet Kuil 307, near Beaufort West. Only two of these sandstones are mineralised. These are four surface and two subsurface uranium anomalies and one surface uranium anomaly. The sedimentological study was made by means of 47 vertical profiles measured across and adjacent to the surface anomalies as well as 11 core-logs, which intersected the subsurface anomalies. The unmineralised sandstones are included in this study. A total of 19 sedimentary facies was recognised within the fluvial sandstone sequence according to the criteria of grain-size and sedimentary structure. Transitions between the facies were subjected to a Markov chain analysis in order to delineate Markov-dependent transitions. Uranium mineralisation is almost entirely confined to the coarser-grained sedimentary facies, which probably acted as suitable aquifers for the transport of uraniferous solutions prior to the precipitation of the uranium. Horizontally bedded sandstone facies comprises 60 per cent of the total cumulative thickness of mineralisation. The nature of the bedding of this facies may have provided a more effective permeability zone for the transport of uraniferous solutions. This facies contains an abundance of carbonaceous material which acted as an important indirect reductant for the precipitation of uranium from solution. The direct reductant was most probably H 2 S produced by enaerobic bacteria acting on this carbonaceous material shortly after deposition of the sediments. Carbonaceous material also occurs in the other mineralised facies and is considered to be the major control on the mineralisation in the uranium-bearing sandstones

Inventory of uranium prospect area Rantau Prapat North Sumatra: general prospection stage

International Nuclear Information System (INIS)

Wusana, Y.; Djalil, A.; Sriyono; Sutriyono, A.; Sajiyo

2000-01-01

The research has been carried out to gain knowledge of geology, radiometry, geochemistry to bound U prospect area scale 1:50.000. Based on investigation result of preliminary prospection was obtained indication of uranium mineralization as stream sediment anomalies in meta sandstone (Perm-Carboniferous) 0.86-28.00 ppm, sandstone (Middle-Upper Miosen) 1.192-7.20 ppm, granite (Upper Permian) 10.71-12.00 ppm; The total U content in sandstone until 10.29 ppm, granite 33.24 ppm, and radiometry of stand stone 25-150 cps, granite 200-500 cps. Lithology of the prospect area consist of quartzite, phyllitte, sandstone, siltstone, clay stone, conglomerate, granite, quartz feldspatic veins, andesite, tufaceous. Strike slip fault, normal fault, foliation and folding has been obtained in these area. Uranium anomalies of stream sediments were found in Conglomerate-Stand stone (1.04-4.80) ppm, Quartzite-Phyllite (0.91-1.90) ppm and Granite units (9.81-13.20) ppm. Uranium content of Conglomerate-stand stone (2.5-5) ppm, quartzite-phyllite (3.0-46.0) ppm, tuffaceous (9.0-22.0) ppm and granite (biotite muscovite) (23.5-40.0) ppm. Granite in these area is as uranium source. Based on anomaly of stream sediments on Conglomerate-Stand stone unit only about 7.64 km 2 , Quartzite-Phyllite 12.04 km 2 , Granite 10.20 km 2 and no supported by heavy mineral anomalies, radiometry and U rock content, so it was advised to not investigate follow up. (author)

Uranium mineralization environment and prospecting potential of Dawan ore field in Nanling metallogenic belt

International Nuclear Information System (INIS)

Yang Shanghai

2011-01-01

Located in the middle part of Jiuyishan complex pluton, Nanling metallogenic belt, Dawan uranium ore field in Hunan Province is an important uranium-producing and rare metal, nonferrous metal cluster area due to the favourable mineralization environment. The Cambrian is the main uranium source bed and their contact zone to the pluton is the favorable part for mineralization. The uranium deposits which have been explored are all located in the exocontact zone of Jinjiling pluton in the middle part of Jiuyishan complex pluton which is composed of the independent eastern and western magma evolution centers. In the west center, Jinjiling pluton is closely related to uranium mineralization where the trinity geologic setting was formed with magma evolution, hydrothermal fluid action and mineralization. The deep slitted and large faults provide the pathway and thermodynamic source for circulating migration of mineralizing fluid. The uranium mineralization mainly occurred in crustal stress conversion period of Late Cretaceous and related to the tensive NW extending fault and deep originated fluid. The gravity, aero magnetic, airborne gamma-ray spectrometry anomalies and radioactivity hydrochemical anomaly are important criteria for uranium prospecting. Based on the analysis of regional uranium mineralization environment, the prospecting potential is forecasted. (authors)

Method for analysing radium in powder samples and its application to uranium prospecting

International Nuclear Information System (INIS)

Gong Xinxi; Hu Minzhi.

1987-01-01

The decayed daughter of Rn released from the power sample (soil) in a sealed bottle were collected on a piece of copper and the radium in the sample can be measured by counting α-particles with an Alphameter for uranium prospection, thus it is called the radium method. This method has many advantages, such as high sensitivity (the lowest limit of detection for radium sample per gram is 2.7 x 10 -15 g), high efficiency, low cost and easy to use. On the basis of measuring more than 700 samples taken along 20 sections in 8 deposits, the results show that the radium method is better than γ-measurement and equal to 210 Po method for the capability to descover anomalies. The author also summarizes the anomaly intensities of radium method, 210 Po method and γ-measurement respectively at the surface with deep blind ores, with or without surficial mineralization, and the figures of their profiles and the variation of Ra/ 210 Po ratios. According to the above-mentioned distinguishing features, the uranium mineralization located in deep and/or shallow parts can be distinguishd. The combined application of radium, 210 Po and γ-measurement methods may be regarded as one of the important methods used for anomaly assessment. Based on the experiments of the radium measurements with 771 stream sediments samples in an area of 100 km 2 , it is demonstrated that the radium mehtod can be used in the stages of uranium reconnaissance and prospecting

Semi-detailed uranium geochemical survey in Northwestern Samar (27 March 1979 - 4 July 1979)

International Nuclear Information System (INIS)

Santos, G. Jr.; Ogena, M.; Tauli, G.

1980-04-01

A uranium geochemical survey was conducted to delineate in detail the uranium prospective area(s) in northwestern Samar. A total of 805 stream sediments and 1.115 water samples were obtained from the target areas from uranium analysis. Geochemical anomalies were indicated in San Isidro and Mauo. Geochemical correlations between uranium and trace elements (Pb, Ag, Ni, Cu, Co, Zn and Mn) were generally poor. (ELC)

210Po measurement of borehole core and its significance for uranium exploration

International Nuclear Information System (INIS)

Chao Xiaolin

2007-01-01

210 Po survey is a tradition method in uranium exploration and has been widely applied to ground reconnaissance survey and detailed survey of uranium. However, it is seldom applied to drilling work. 210 Po measurements of borehole core for granite-type uranium deposit in Miaoershan area indicate that there are high and large range anomaly which greatly exceeds uranium orebody in uranium mineralization area. The investigation suggests that 210 Po measurements of borehole core can judge whether or not exist buried uranium orebody under the borehole depth and its surrounding in the final exploration stage. The method may be used to the exploration of granite-type uranium deposit. (authors)

Results of solid state nuclear track detector technique application in radon detection, by alpha particles tracks, for uranium prospecting in Caetite (BA-Brazil)

International Nuclear Information System (INIS)

Moraes, M.A.P.V. de; Khouri, M.T.F.C.

1988-11-01

The solid state nuclear track detector technique has been used in radon detection, by alpha particles tracks for uranium prospecting on the ground in Caetite city (Bahia-Brazil). The sensitive film to alpha particles used were CA 8015 exposed during 15 days and the results of three anomalies of this region are showed in a form of maps, made with the density of tracks obtained, and were compared with scintillation counter measurements. The technique showed to be simple and an effective auxiliary for the prospection of uranium ore bodies. The initial uranium exploration costs can be reduced by using this technique. (author) [pt

Geology and uranium occurrences in the Forez tertiary plain (in the French 'Massif Central')

International Nuclear Information System (INIS)

Duclos, P.

1967-01-01

In the first part, the observations made during the geological survey of the Forez Tertiary plain (in the French 'Massif Central') are recalled. Then, using various methods, the author lists the formations according to chronology. Finally, a reconstitution of the geological history of this subsidence basin is attempted. In the second part, the occurrence of 17 uranium bearing geochemical anomalies is commented upon. Each of these various anomalies is given a place on the stratigraphic scale. This enables the author to put the successive phases of uranium deposition into their proper perspective in the history of the plain. In conclusion, the author points out the usefulness of these uraniferous geochemical anomalies. (author) [fr

Potential uranium host rocks and structures in the central Great Plains

International Nuclear Information System (INIS)

Zeller, E.J.; Dreschhoff, G.; Angino, E.; Holdoway, K.; Hakes, W.; Jayaprakash, G.; Crisler, K.; Saunders, D.F.

1975-01-01

A preliminary study was completed of the uranium potential of the Central Great Plains. The study area extends from longitude 99 to 104 0 W and is bounded by the North Platte River on the north and the Canadian River on the south. This region has no known commercial uranium accumulations, but is an area which contains formations with similar facies that are known to have deposits in other areas. A new method of utilizing petroleum exploration gamma-ray well log data was tested in the western Kansas portion of the survey area. Gamma activities in the Dakota and Morrison formations were computer-processed by trend surface analysis, statistically analyzed, and the anomalies were compared with regional geomorphic lineaments derived from satellite imagery as well as regional geology, to draw conclusions as to their origin and significance. Conclusions are: (1) possible uraniferous provinces have been outlined in the subsurface of western Kansas; (2) the new well log data approach can be used to define potential uraniferous provinces in any well-explored petroleum region; (3) the close spatial correlation between anomalies and regional geomorphic lineaments provides strong support for the concept that the lineaments represent vertical fracture zones which can act as preferred pathways for vertical fluid migration; and (4) the location of the strongest anomalies over impervious salt bodies indicates that any uranium bearing mineralizers must have moved down through the geologic section rather than upward. Recommendations are made to extend the application of the well-log approach, to do drilling and sampling to prove whether the anomalies are really due to uranium, and to add geobotanical and emanometric measurements during future studies

Interpretation of the phosphate showings found in Uruguay. Recommendations for a a working programme

International Nuclear Information System (INIS)

Slansky, M.

1983-01-01

The radioactive anomalies put in evidence during the investigation of uranium and the mining inventory carried out in Uruguay, are due to rocks more or less strongly phosp hated of the top proterozoic and of the paleozoic. These anomalies drive to interrogating ourselves on the possibilities of existence of deposits of phosphates exploitable

Geochemical exploration for uranium

International Nuclear Information System (INIS)

Rose, A.W.

1977-01-01

The processes and types of dispersion that produce anomalies in stream water, stream sediment, and ground water, and the factors that must be considered in planning and interpreting geochemical surveys are reviewed. Examples of surveys near known deposits show the types of results to be expected. Background values depend mainly on the content of U in rocks of the drainage area. In igneous rocks, U tends to increase with potassium from ultramafic rocks (0.01 ppM) to granitic rocks (1 to 5 ppM). Some alkalic rocks have unusually high contents of U (15 to 100 ppM). Uranium-rich provinces marked by igneous rocks unusually rich in U are recognized in several areas and appear to have a deep crustal or mantle origin. In western U.S., many tertiary tuffaceous rocks have a high U content. Sandstones, limestones, and many shales approximate the crustal abundance at 0.5 to 4 ppM, but black shales, phosphates, and some organic materials are notably enriched in U. Uranium is very soluble in most oxidizing waters at the earth's surface, but is precipitated by reducing agents (organic matter, H 2 S) and adsorbed by organic material and some Fe oxides. In most surface and ground waters, U correlates approximately with the total dissolved solids, conductivity, and bicarbonate concentration of the water, and with the U content of rocks it comes into contact with. Most surveys of stream water near known districts show distinct anomalies extending a few km to tens of km downstream. A complication with water is the large variability with time, up to x 50, as a result of changes in the ratio of ground water to direct runoff, and changes in rate of oxidation and leaching. Collection and analysis of water samples also pose some difficulties

National uranium resource evaluation, Rapid City Quadrangle, South Dakota

International Nuclear Information System (INIS)

Nanna, R.F.; Milton, E.J.

1982-04-01

The Rapid City (1 0 x 2 0 ) Quadrangle, South Dakota, was evaluated for environments favorble for uranium deposits to a depth of 1500 m. Criteria used were those of the National Uranium Resource Evaluation. Field reconnaissance involved the use of hand-held scintillometers to investigate uranium occurrences reported in the literature and anomalies in aerial radiometric surveys, and geochemical samples of stream sediments and well waters. Gamma-ray logs were used to define the favorable environments in the subsurface. Environments favorable for sandstone-type uranium deposits occur in the Inyan Kara Group, the Fox Hills Sandstone, and the Hell Creek Formation. Environments considered unfavorable for uranium deposits include all Precambrian, Paleozoic, Mesozoic, and Tertiary rocks other than those identified as favorable

Report about drilling works made in 13 Anomaly de Taylor and in the N- NE of its, around Fraile Muerto (Cerro Largo district): Uranium project[Study of Uranium prospection in Uruguay]; Informe sobre los trabajos de perforacion efectuados en la Anomalia 13 de Taylor y al N-NE de la misma , en los alrededores de Fraile Muerto (Departamento de Cerro Largo). Proyecto Uranio

Energy Technology Data Exchange (ETDEWEB)

Massa, J; Pirelli, H

1983-07-01

The perforations were carried out to investigate in depth denominated anomaly 13 detected during the Taylor Mission (1975) and extended the punch area of study during you are suitable DINAMIGE-BRGM (Project the present report details the activities realised in the environs Fraile Muerto (Cerro Largo district) by the command team of perforations of the uranium project. Previously and contemporarily to the executed works, prospection became geophysical ground geochemistry geology and, works. (Uranium)

The relationship between uranium distribution and some major crustal features in Canada

International Nuclear Information System (INIS)

Darnley, A.G.

1982-01-01

The availability of reconnaissance scale geochemical maps for large areas of Canada enables spatial associations between major crustal structures and surface uranium content to be identified. Maps of the distribution of uranium for an area greater than 2 million km 2 compiled from airborne gamma-ray spectrometry data are supplemented by maps for uranium, based on stream and lake sediment and some bore hole sampling. These are examined in relation to gravity, aeromagnetic and geological maps. The radioelement distribution can be related in detail to exposed bedrock and surface geology, but in addition there is evidence of the control of uranium distribution by major structural features which are marked by granitoids containing elevated levels of radioelements; several of these granitoids are associated with large negative Bouguer gravity anomalies. The distribution of such granitoids appears to be related to 'megashears', as in the case of the South Mountain batholith in Nova Scotia, or zones of tension. A belt of uranium enrichment, the Athabasca axis which is characterized by uraniferous granitoids with negative Bouguer gravity anomalies and associated tension faulting extends 2500 km northeastward from Edmonton, Alberta to the Melville Peninsula. This structure passes under the Athabasca basin which contains many large uranium deposits. (author)

Petrography, mineral chemistry and lithochemistry of the albitite and granite-gneissics rocks of anomaly 35 from Lagoa Real uranium province

International Nuclear Information System (INIS)

Santos, Camila Marques dos

2016-01-01

albitites and gneisses are macroscopically gradational, however, in the garnet albitites replacement of granitic mineral facies by the albitite facies were observed petrographically, implying a granitic protolith for this rock. On the other hand, magnetite albitites do not have clear relationship with granites. Albitites usually have porphyroblastic texture with granoblastic polygonal matrix and chessboard texture in albite porphyroclasts. The garnet albitites comprise hedenbergite, hastingsite, garnet, magnetite and sphena. Magnetite albitites, in turn, have hedenbergite, Fe-edenite, biotite, martitized magnetite, allanite and sphene. The diopside+actinolite+eastonita association is late, and in these rocks, it is restricted to more deformed portions or filling voids. The biotite albitites comprise biotite, zircon and apatite hedenbergite (?). Mineralization occurs in magnetite albitites as thin lenses composed by sphene, magnetite, carbonate and zircon. The uranium mineral is the uraninite, which occurs filling spaces between crystals and sphene or albite granules. In comparison to granites, albitites have a higher content of Na 2 O, MgO, V, W, Zr, Pb and Sr for and lower K 2 O, SiO 2 and F. They have a geochemical REE pattern that is identical to that of granite. The similarity between macroscopic granites and albitites, the presence of vazios, feldspar hematitization and sericitization causing macroscopical reddening in transitional portions and the replacement of potassic feldspar by albite and oligoclase are suggestive of episyenitization processes. The metasomatic perthites and presence of chessboard texture in porphyroclasts indicate successive albitization processes prior to deformation. The comparison between albitite samples of different drill cores and anomalies shows that there are differences in the formation and mineralization of these rocks. The V and Mg enrichment in some albitites suggests that these rocks may result from the interaction of fluids with

Uranium, plutonium, and thorium isotopes in the atmosphere and the lithosphere

International Nuclear Information System (INIS)

Essien, I.O.

1983-01-01

Concentration of 238 U in rain and snow collected at Fayetteville (36 0 N, 94 0 W), Arkansas, showed a marked increase during the summer months of 1980, while Mount St. Helens remained active. This observed increase of 238 U can be explained as due to the fallout of natural uranium from the eruption of Mount St. Helens. Large increases in the concentration of thorium isotopes detected in rain and snow samples during the last months of 1982 and early months of 1983 probably originated from the eruption of El Chichon volcano, which occurred on 28 March 1982. About 450 Ci of 232 Th is estimated to have been injected into the atmosphere by this eruption. Isotopic anomalies were observed in atmospheric samples such as rain and snow. These anomalies can be attributed to various natural as well as man-made sources: nuclear weapon tests, nuclear accidents involving the burn-up of nuclear powered satellites, and volcanic eruptions. The variation of 234 U/ 238 U ratios in radioactive minerals when leached with nitric acid were also noticed and this variation, while 235 U/ 238 U remained fairly constant, can be explained in terms of the α-recoil effect and changes in oxidation state of uranium. Difference found in 239 Pu/ 238 U ratios in terrestrial samples and uranium minerals can be explained as due to fallout contamination

Exploration of Uranium. Report to the Government of the Eastern Republic of Uruguay

International Nuclear Information System (INIS)

Muset, J.A.

1979-01-01

The Government of Uruguay with IAEA assistance carried out the Uranium prospection project and the evolution of uraniferous minerals resources on this country soil. Several arrangement were did such as the recollection and analysis of the geologic material. The Uranium project began with radiometric anomalies and out crops

National Uranium Resource Evaluation, Llano Quadrangle, Texas

International Nuclear Information System (INIS)

Droddy, M.J.; Hovorka, S.D.

1982-04-01

The Llano 2 0 quadrangle was evaluated to a depth of 1500 m to identify environments and delineate areas favorable for the occurrence of uranium deposits. The areas were delineated according to criteria established for the National Uranium Resource Evaluation program. Surface studies included investigations of uranium occurrences described in the literature, location of aerial radiometric anomalies, carborne scintillometer surveys, outcrop investigations, and followup of hydrogeochemical and stream-sediment reconnaissance data. A radon emanometry survey and investigations of electric and gamma-ray well logs, drillers' logs, and well core samples were performed to evaluate the subsurface potential of the Llano Quadrangle. An environment favorable for pegmatitic deposits is identified in the Town Mountain Granite

Birth effects in areas of uranium mining

International Nuclear Information System (INIS)

Wiese, W.H.

1981-01-01

A study of the reproductive history of families of 26 former uranium miners and 30 controls in San Juan County, New Mexico is presented. Studies of the secondary sex ratios, cytogenetic study of human sperm, and studies of rates of congenital anomalies are reported

National Uranium Resource Evaluation, Tularosa Quadrangle, New Mexico

International Nuclear Information System (INIS)

Berry, V.P.; Nagy, P.A.; Spreng, W.C.; Barnes, C.W.; Smouse, D.

1981-12-01

Uranium favorability of the Tularosa Quadrangle, New Mexico, was evaluated to a depth of 1500 m using National Uranium Resource Evaluation criteria. Uranium occurrences reported in the literature were located, sampled, and described in detail. Areas of anomalous radioactivity, interpreted from an aerial radiometric survey, and geochemical anomalies, interpreted from hydrogeochemical and stream-sediment reconnaissance, were also investigated. Additionally, several hundred rock samples were studied in thin section, and supplemental geochemical analyses of rock and water samples were completed. Fluorometric analyses were completed for samples from the Black Range Primitive Area to augment previously available geochemical data. Subsurface favorability was evaluated using gamma-ray logs and descriptive logs of sample cuttings. One area of uranium favorability was delineated, based on the data made available from this study. This area is the Nogal Canyon cauldron margin zone. Within the zone, characterized by concentric and radial fractures, resurgent doming, ring-dike volcanism, and intracauldron sedimentation, uranium conentration is confined to magmatic-hydrothermal and volcanogenic uranium deposits

National Uranium Resource Evaluation: Bozeman Quadrangle, Montana

International Nuclear Information System (INIS)

Lange, I.M.; Fields, R.W.; Fountain, D.M.; Moore, J.N.; Qamar, A.I.; Silverman, A.J.; Thompson, G.R.; Chadwick, R.A.; Custer, S.G.; Smith, D.L.

1982-08-01

The Bozeman Quadrangle, Montana, was evaluated to identify and delineate areas containing environments favorable for uranium deposits. This evaluation was conducted using methods and criteria developed for the National Uranium Resource Evaluation program. General surface reconnaissance, mapping, radiometric traverses, and geochemical sampling were performed in all geologic environments within the quadrangle. Aerial radiometric and HSSR data were evaluated and followup studies of these anomalies and most of the previously known uranium occurrences were conducted. Detailed gravity profiling was done in the Tertiary Three Forks-Gallatin Basin and the Madison and Paradise Valleys. Also, selected well waters were analyzed. Eight areas are considered favorable for sandstone uranium deposits. They include the Tertiary Three Forks-Gallatin basin, the Madison and Paradise Valleys, and five areas underlain by Cretaceous fluvial and marginal-marine sandstones. Other environments within the quadrangle are considered unfavorable for uranium deposits when judged by the program criteria. A few environments were not evaluated due to inaccessibility and/or prior knowledge of unfavorable criteria

National Uranium Resource Evaluation: Bozeman Quadrangle, Montana

Energy Technology Data Exchange (ETDEWEB)

Lange, I.M.; Fields, R.W.; Fountain, D.M.; Moore, J.N.; Qamar, A.I.; Silverman, A.J.; Thompson, G.R.; Chadwick, R.A.; Custer, S.G.; Smith, D.L.

1982-08-01

The Bozeman Quadrangle, Montana, was evaluated to identify and delineate areas containing environments favorable for uranium deposits. This evaluation was conducted using methods and criteria developed for the National Uranium Resource Evaluation program. General surface reconnaissance, mapping, radiometric traverses, and geochemical sampling were performed in all geologic environments within the quadrangle. Aerial radiometric and HSSR data were evaluated and followup studies of these anomalies and most of the previously known uranium occurrences were conducted. Detailed gravity profiling was done in the Tertiary Three Forks-Gallatin Basin and the Madison and Paradise Valleys. Also, selected well waters were analyzed. Eight areas are considered favorable for sandstone uranium deposits. They include the Tertiary Three Forks-Gallatin basin, the Madison and Paradise Valleys, and five areas underlain by Cretaceous fluvial and marginal-marine sandstones. Other environments within the quadrangle are considered unfavorable for uranium deposits when judged by the program criteria. A few environments were not evaluated due to inaccessibility and/or prior knowledge of unfavorable criteria.

INTURGEO: The international uranium geology information system

International Nuclear Information System (INIS)

1988-09-01

The International Uranium Geology Information System (INTURGEO) is an international compilation of data on uranium deposits and occurrences. The purpose of INTURGEO is to provide a clearinghouse for uranium geological information that can serve for the better understanding of the worldwide distribution of uranium occurrences and deposits. The INTURGEO system is by no means complete for all regions of the world. Data have been available principally from the WOCA countries. INTURGEO currently covers 6,089 occurrences and deposits in 96 countries of which 4,596 occurrences in 92 countries are presented here. The information presented in this publication is a very brief, one line synopsis of deposits and occurrences, and has been collected from literature and through questionnaires sent directly to IAEA Member States. None of the information contained in the INTURGEO database was derived from confidential sources although there are many entries which come from the internal files of Member States and are not directly available in the general literature. The uniformity of the INTURGEO data presented in this report has depended heavily on the data provided by Member States. Basic information includes the deposit or occurrence name, the mining district, the tectonic setting, the geological type, status, size, host-rock type, age of mineralization and bibliographic references. The data contained in the maps of the atlas include all reported occurrences of uranium above the anomaly level. The categories of occurrence and deposit status includes: Anomaly; occurrences of unknown status; occurrences; prospects; developed prospects; subeconomic deposits; economic deposits; mines; inactive mines; depleted mines. A microcomputer version of INTURGEO on 21 Megabyte Bernoulli disks is available. 5 tabs, 102 maps

Evaluation of uranium anomalies in the Hylas zone and northern Richmond basin, east-central Virginia

International Nuclear Information System (INIS)

Baillieul, T.A.; Dexter, J.J.

1982-01-01

Conclusions from this study are: (1) Radon values in ground water from the Hylas Zone and the adjacent Richmomd Basin are anomalous and may indicate nearby uranium-enriched source rocks. (2) Pegmatites, protomylonitic granite, and the Petersburg Granite can be good sources of uranium for ground water. The pegmatites described in this report appear to be the best source rocks because of uranium values ranging from 82 to 235 ppM eU and corresponding low values of Th as well (average Th/U = 0.18). The protomylonitic granite has an average Th/U ratio of 0.5. Ground-water samples (ranging from 70 to 270 ppB uranium) from southwest Richmond are believed to have originated from a major ground-water system at the contact of the Petersburg Granite and overlying coastal plain sediments. Thus, the Petersburg Granite may be considered a possible source of uranium available to ground water entering the Richmond Basin. (3) The Richmond Basin could host uranium deposits of the sandstone class. As mentioned above, there appears to be an adequate supply of uranium in rocks surrounding the basin. The basin environment is presently classified as unevaluated. Further work is warranted on the basis of this study. (4) Pegmatites in the Hylas Zone could be favorable for the occurrence of uranium deposits of the pegmatitic class. However, it is not known how the uranium occurs in the pegmatites, and only pegmatites exposed in the Boscobel quarry were examined. Therefore, this environment remains unevaluated. 3 figures, 4 tables

Geochemistry of stream sediments, water and U-Th radiation anomaly around Neyshabour Fyrouzeh mine and its environmental impact on people living nearby villages

International Nuclear Information System (INIS)

Karimpour, M. H.; Malekzadeh Shafaroudi, A.

2013-01-01

Fyrouzeh mine is located about 55 km northwest of Neyshabour in the Province of Khorasan Razavi. The exposed rocks are mainly volcanic and intrusive with intermediate composition and all of them are altered. This mine is the first type of IOCG recognized in Iran with Cu-Au-LREE-U. Besides Cu-Au-U, this area shows As, Mo, Zn and Th anomalies. Geochemical evaluation of stream sediment with regard to environmental concern revealed high Cu anomalies. Rocks show high uranium anomalies (up to 35 ppm) higher than the standard values (1 ppm). Airborne radiometric maps show high U and Th anomalies in a broad area. Ag, Hg and Mn show anomalies within the stream sediments. Cu, Pb, Zn, Ag, Ni, Mn, Sb, Hg, and U content of both drinking and agricultural water are fortunately within the range of standard, only two samples have higher As content (more than 10 ppb). High level of U-Th radiation and contamination of stream sediment with respect to Cu, Hg, Ag, Mn and agricultural water to As are important environmental issues and people health therefore they need to be study.

Isotopic characterization of uranium in soils of the Ipanema National Forest (FLONA-Ipanema)

International Nuclear Information System (INIS)

Silva, F.B.; Marques, F.H.; Enzweiler, J.; Ladeira, F.S.B.

2015-01-01

The National Forest of Ipanema (FLONA) is situated on a geological anomaly, known as 'Domo de Aracoiaba'. The soils of the area include Oxisols, Inceptsols and Alfisols. The amount of uranium and respective isotope activities in a soil depend on the parental rock and on the pedologic processes. The aim of this study was to investigate the activities for uranium isotopes ("2"3"8U, "2"3"4U, "2"3"5U) and the activity ratio (AR) "2"3"4U/ "2"3"8U or secular equilibrium for different soil types of the area collected at horizons A and B. The amount of uranium showed no significant differences for soils generated from alkaline intrusive rocks and sandstone, however, secular equilibrium was observed for Oxisol (RA = 1), while Inceptsol presented RA> 1 and the other soils, Alfisols, presented RA values <1. (author)

Uranium, thorium and rare earth elements distribution from different iron quadrangle spring waters

International Nuclear Information System (INIS)

Ferreira, Cláudia A.; Palmieri, Helena E.L.; Menezes, Maria A. de B.C.; Rodrigues, Paulo C.H.

2017-01-01

This study was conducted to evaluate the concentrations of thorium, uranium and the rare earth elements (REE) in 26 spring waters, as well as the patterns of the REE of the samples from the Cercadinho, Moeda and Caue aquifers in different municipalities of the Iron Quadrangle (Quadrilatero Ferrifero), located in the central-southeast of Minas Gerais state. The pH value of the ground waters ranged from 3.8 to 7.0, indicating an acid nature of most of the spring waters. The investigation of REE speciation showed that all the REEs exist in the free X"3"+ ionic forms, under the prevailing Eh and pH conditions. In the studied samples the uranium concentrations ( 1000 ng L"-"1) originating from aquifers located in Sabara, Barao de Cocais, Santa Barbara, Mario Campos, Congonhas and Lavras Novas. The REEs patterns in the spring waters from the Cercadinho, Caue and Moeda aquifers are characterized by middle REE (MREE) enrichment compared to light REE (LREE) and heavy REEs (HREE), negative Ce anomalies (except for one sample) and positive Eu anomalies in all three aquifers studied. (author)

Advances in the knowledge of the mining geological anomaly uraniferous Medano Rico, Disc. Jachal, San Juan Province

International Nuclear Information System (INIS)

Matar, M.; Arroqui, A.; Wetten, A.; Banchig, P.; Iglesias, R.

2010-01-01

Preliminary results of research carried out in the area of ​​Medano Rico, Dto Jachal San Juan Province, under the project Implementation of a model for exploration of uranium in Pre cordillera describes this work. The research tasks are intended to deepen the knowledge of the area to establish a genetic model of uranium anomaly

International Uranium Resources Evaluation Project (IUREP) national favourability studies: Saudi Arabia

International Nuclear Information System (INIS)

1977-09-01

Saudi Arabia occupies most of the Arabian Peninsula and has an area of 872,722 sq miles, or 2,260,350 sq km. The ancient Arabian Shield of igneous and metamorphic rocks comprises most of the western third of the country. The shield contains many extinct volcanoes surrounded by lava beds. Sloping eastwards are the newer sedimentary areas in which rich oil fields are found. In Saudi Arabia oil is paramount and less effort has been put into searching for mineral deposits than in other countries of similar size and geology. Pour aerial radiometric surveys have been undertaken and some of the anomalies discovered in the earlier ones were ground checked by an IAEA expert in 1963-64. Two anomalies warranted more detailed work, these were the Jabal Said anomaly in the Central Shield area and the Al Ghrayyat in Wadi Sawawin about 70 miles from the Jordan border. The Jabal Said anomaly consists of a zone of altered rocks consisting largely of pegmatite and pegmatite granite= Allanite, pyrochlore, cyrtolite, xenotime and monazite are the ore minerals,, The deposit was estimated to have 2.2 million tons of ore grading 0.2 - 0.3 percent Nb 2 O 5 and 0.03 - 0,05% U 3 O 8 . The other occurrence at Al Ghrayyat is similar but with much lower grade uranium content. In view of the huge size of Saudi Arabia, the existence of many geologically favourable rock types and the poor coverage by sophisticated uranium exploration techniques, the Speculative Potential is placed between 10,000 and 50,000 Tonnes uranium. (author)

Geochemical behaviour of uranium in the cycle of alteration; Comportement geochimique de l'uranium dans le cycle d'alteration

Energy Technology Data Exchange (ETDEWEB)

Chervet, J; Coulomb, R [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires; Soudan, P [Centre d' Etude de Lalumine, Compagnie Pechiney (France)

1958-07-01

The investigation of the genesis of secondary mineralized accumulations, and the prospecting of deposits from microchemical anomalies in the surface material, is requiring a well-developed knowledge of the geochemical properties of the uranium during the alteration phase. In the present work, the authors tried to track the uranium history during a part of his natural creeping. a) They describe some most typical mineralogical observations of alteration phenomena and material migration, picked up in place on the deposits. b) They give experimental results concerning the solubilities of the uranium minerals and the factors affecting this solubility. c) They study the water circulation in granitic batholites, and the influence of the occurrence of the uranium deposits on their composition. d) They observe the amplitude of phenomena restricting the dispersions: fixations, precipitations, etc., and the behaviour of growth in uraniferous areas. e) Finally, the opposition chemical alteration-radioactive equilibrium results in an important imbalance in altered materials. The authors tried to use the measurement of this imbalance to explain geochemical processes. (author) [French] L'etude des conditions de genese des accumulations minerales secondaires, ainsi que la prospection des gisements a partir d'anomalies microchimiques dans les materiaux de surface, necessite une connaissance approfondie des proprietes geochimiques fondamentales de l'uranium dans la phase d'alteration. Nous essayons, dans ce travail, de suivre l'histoire de l'uranium dans une partie de son cheminement naturel. a) Nous decrivons quelques observations mineralogiques particulierement typiques de phenomenes d'alteration et de migration de matiere, prises 'in situ' dans les gisements. b) Nous donnons les resultats d'experiences de laboratoire sur les solubilites de mineraux d'uranium et sur les facteurs influen nt cette solubilite. c) Nous etudions les circulations d'eaux sur les massifs granitiques et

Chemical aspects of uranium behavior in soils: A review

Science.gov (United States)

Vodyanitskii, Yu. N.

2011-08-01

Uranium has varying degrees of oxidation (+4 and +6) and is responsive to changes in the redox potential of the environment. It is deposited at the reduction barrier with the participation of biota and at the sorption barrier under oxidative conditions. Iron (hydr)oxides are the strongest sorbents of uranium. Uranium, being an element of medium biological absorption, can accumulate (relative to thorium) in the humus horizons of some soils. The high content of uranium in uncontaminated soils is most frequently inherited from the parent rocks in the regions of positive U anomalies: in the soils developed on oil shales and in the marginal zone of bogs at the reduction barrier. The development of nuclear and coal-fired power engineering resulted in the environmental contamination with uranium. The immobilization of anthropogenic uranium at artificial geochemical barriers is based on two preconditions: the stimulation of on-site metal-reducing bacteria or the introduction of strong mineral reducers, e.g., Fe at low degrees of oxidation.

Investigation of aeration rate on Uranium bio leaching in internal airlift bioreactor

International Nuclear Information System (INIS)

Zolala, M. R.; Safdari, S. J.; Haghighi Asl, A.; Rashidi, A.

2012-01-01

Uranium is leached from the uranium ore of the second anomaly of Saghand by the Acidithiobacillus ferroxidans bacteria in an internal airlift bio-reactor. This study has been made to find the effect of aeration rate as well as its optimal value. The experiments have been carried out at 4 aeration rates to find the best recovery results in the least possible time duration. The results showed that the most percentage of the uranium recovery is in the superficial gas velocity of 0.010 m/s. The recovery at this aeration rate has an efficiency of more than 95 p ercent i n 11 days. Also, the best range for aeration study in the airlift bio-reactor is calculated with a minimum value of 0.0065 m/s which is the critical value of the uranium particle suspension as well as the maximum value of 0.015 m/s. The stress on the bacteria increases the recovery time process in velocities of more than 0.015 m/s.

Depth study of insular shelf electric sounding Adelaida anomaly (Rivera)

International Nuclear Information System (INIS)

Cicalese, H.

1983-01-01

In the framework of the Uranium prospecting programme, the DINAMIGE geophysical equipment have made a study. It was about the depth of insular shelf electric sounding on the anomalies zone of Adelaida. This equipment carried out a study of the following subjects: geographical location, geologic framework, geophysical intervention, developed works, methods and material and results

Airborne radiometric anomalies caused by late kinematic granite rocks in the Molson Lake-Red Sucker Lake area, east-central Manitoba

International Nuclear Information System (INIS)

Weber, W.; Schledewitz, D.C.P.; Soonawala, N.M.

1982-01-01

Geological mapping with simultaneous ground gamma ray spectrometer surveys in an area with a chain of airborne radiometric anomalies of greater than 2 ppm eU indicate uranium enrichment in late kinematic pink leucogranitic rocks including granites, alaskites, and syenites which form dykes, stocks and small plutons in a batholithic tonalite - granodiorite complex. Field geolocial evidence suggests that the potassium-rich rocks were formed by hydrothermal solutions and that at least some of them are metasomatic replacement bodies. Results of geophysical grid survey over a pronounced anomaly indicate that it is caused by a significant volume of leucogranitic rocks with an unusually high background concentration of uranium averaging 25 ppm eU. The uranium seems to be associated with hematite which coats mineral grains and fills small fractures

Analysis on uranium metallogenetic conditions of granite pluton in Ulan Uzhur

International Nuclear Information System (INIS)

Lu Yaozu

2014-01-01

Qimantage area in Qinghai province is one of the important exploration areas in the present China, Ulan Uzhur complex pluton, located in the compound tectonic magmatic belt of Qimantage, is the main cluster area with uranium mineralization. This paper describes the petrochemical, geochemical, petrophysical and Heishan uranium deposit mineralization characteristics of rocks formed at the different tectonic-magmatic cycles in Ulan Uzhur complex pluton. Uranium metallogenic conditions in Ulan Uzhur complex pluton were analyzed from uranium source, magmatic activity and structure. The research shew that the Ulan Uzhur complex pluton has the petrochemical characteristics of uranium rock and Cisuralian monzonitic granite has the most significant relationship to uranium mineralization, it has the characteristics of high background radiation, many anomalies and pronounced ore-control structure, Heishan uranium deposit was controlled by factors such as pronounced northeast and the northwest structure and alteration. To conclude, Ulan Uzhur complex pluton possesses good uranium metallogenic prospect. (author)

National Uranium Resource Evaluation: Albany Quadrangle, Massachusetts, New York, Connecticut, Vermont, and New Hampshire

Energy Technology Data Exchange (ETDEWEB)

Field, M T; Truesdell, D B

1982-09-01

The Albany 1/sup 0/ x 2/sup 0/ Quadrangle, Massachusetts, New York, Connecticut, Vermont, and New Hampshire, was evaluated to a depth of 1500 m for uranium favorability using National Uranium Resource Evaluation criteria. Areas of favorable geology and aeroradioactivity anomalies were examined and sampled. Most Triassic and Jurassic sediments in the Connecticut Basin, in the central part of the quadrangle, were found to be favorable for sandstone uranium deposits. Some Precambrian units in the southern Green Mountains of Vermont were found favorable for uranium deposits in veins in metamorphic rocks.

National Uranium Resource Evaluation: Albany Quadrangle, Massachusetts, New York, Connecticut, Vermont, and New Hampshire

International Nuclear Information System (INIS)

Field, M.T.; Truesdell, D.B.

1982-09-01

The Albany 1 0 x 2 0 Quadrangle, Massachusetts, New York, Connecticut, Vermont, and New Hampshire, was evaluated to a depth of 1500 m for uranium favorability using National Uranium Resource Evaluation criteria. Areas of favorable geology and aeroradioactivity anomalies were examined and sampled. Most Triassic and Jurassic sediments in the Connecticut Basin, in the central part of the quadrangle, were found to be favorable for sandstone uranium deposits. Some Precambrian units in the southern Green Mountains of Vermont were found favorable for uranium deposits in veins in metamorphic rocks

A coalescence model for uranium exploration

International Nuclear Information System (INIS)

Stuart-Williams, V.; Taylor, C.M.

1983-01-01

Uranium mineralization was found in the Pristerognathus-Diictodon Assemblage Zone of the Teekloof Formation, Beaufort Group, west of Beaufort West, Cape Province, South Africa. All the anomalies can be related to a single mineralization model. Mineralization is found at the termination of a silt parting between two coalescing sandstones and lies in the lower sandstone as an inclined zone dipping downflow from the termination of the silt parting. The existence of primary Eh-pH gradient is indicated by a uranium-molybdenum zonation, the molybdenum lying above the uranium mineralization. The upper sandstone was an oxidizing fluvial channel in an arid environment through which uranyl carbonate was being transported in solution. Carbonaceous material undergoing anaerobic bacterial breakdown generated a weakly reducing fluid in the lower sandstone. Carbonaceous material at the REDOX front developed between the two mixing fluids at the point of sandstone coalescence reduced uranyl carbonates in solution. Once reduced the uranium minerals remained stable because the conditions in the REDOX front were only very weakly oxidizing. As floodplain aggradation continued, the upper sandstone was buried and the entire sandstone couplet became reducing, permanently stabilizing the uranium mineralization

Uranium potential of precambrian rocks in the Raft River area of northwestern Utah and south-central Idaho. Final report

International Nuclear Information System (INIS)

Black, B.A.

1980-09-01

A total of 1214 geochemical samples were collected and analyzed. The sampling media included 334 waters, 616 stream sediments, and 264 rocks. In addition, some stratigraphic sections of Elba and Yost Quartzites and Archean metasedimentary rock were measured and sampled and numerous radiation determinations made of the various target units. Statistical evaluation of the geochemical data permitted recognition of 156 uranium anomalies, 52 in water, 79 in stream sediment, and 25 in rock. Geographically, 68 are located in the Grouse Creek Mountains, 43 in the Raft River Mountains, and 41 in the Albion Range. Interpretation of the various data leads to the conclusion that uranium anomalies relate to sparingly and moderately soluble uraniferous heavy minerals, which occur as sparse but widely distributed magmatic, detrital, and/or metamorphically segregated components in the target lithostratigraphic units. The uraniferous minerals known to occur and believed to account for the geochemical anomalies include allanite, monazite, zircon, and apatite. In some instances samarskite may be important. These heavy minerals contain uranium and geochemically related elements, such as Th, Ce, Y, and Zr, in sufficient quantities to account for both the conspicuous lithologic preference and the generally observed low amplitude of the anomalies. The various data generated in connection with this study, as well as those available in the published literature, collectively support the conclusion that the various Precambrian W and X lithostratigraphic units pre-selected for evaluation probably lack potential to host important Precambrian quartz-pebble conglomerate uranium deposits. Moreover it is also doubted that they possess any potential to host Proterozoic unconformity-type uranium deposits

International Uranium Resources Evaluation Project (IUREP) national favourability studies: Afghanistan

International Nuclear Information System (INIS)

1976-12-01

Although Afghanistan has an extent of some 650,065 square kilometres, only a very small proportion of it has been surveyed for uranium, and that only at the preliminary reconnaissance stage. Earlier work by bi-lateral teams identified a number of small uranium anomalies and occurrences and more recently (1974-75) an IAEA geologist discovered evidence of uranium mineralisation in the Neogene - Lower Pleistocene continental sediments of the Jalalabad Basin to the east of Kabul. The I.A.E.A. expert outlined three areas totalling 20,000 km where systematic uranium exploration would be justified. Up to the present no positive programme has been agreed. On very tenuous evidence a Speculative Potential of 2000 tonnes U 3 O 8 is suggested for Afghanistan. (author)

Uranium deposits of Lagoa Real uranium Province, state of Bahia, Brazil

International Nuclear Information System (INIS)

Ribeiro, C.I.; Carvalho Filho, C.A. de; Hashizume, B.K.

1984-01-01

The Uranium Province of Lagoa Real is situated in the south-central part of the state of Bahia and constitutes, at the present moment, one of the most promising uranium districts of Brazil. The first anomaly was recorded in 1977 and, since then intense exploration and evaluation has been carried out in the area, resulting in the characterization of six ore deposits until now. Simultaneously, NUCLEBRAS has performed tests to establish the beneficiation characteristics of the ore, and developed preliminary mining plans. The host rock for the ore mineralization is related to sodic metasomatism and controlled by lithology and structure. The ore exhibits granoblastic texture, fine to coarse grain size, and the principal uranium minerals are uraninite, and, in minor quantities, pitchblende and uranophane. The solubility is over 90% of the U 3 O 8 contained, with an average acid consumption of 35 Kg per ton of ore treated. This paper presents a brief description of the main ore deposits and touches on their general characterisitcs. As an example, the deposit 'Jazida Cachoeira' is dealt with in greater detail, since this deposit is considered in the present context to be the most important one in the province. (Author) [pt

Detailed geochemical survey for east-central Minnesota, geology and geochemistry of selected uranium targets

International Nuclear Information System (INIS)

Morey, G.B.; Lively, R.S.

1980-01-01

Results of a detailed geochemical survey of approximately 6820 km 2 in parts of Aitkin, Carlton, Kanabec, and Pine Counties, east-central Minnesota are reported. Geochemical data are presented for 883 groundwater samples and 200 bedrock samples. Although all of the groundwaters in the study area have similar major-element concentrations and therefore presumably a common ancestry, small differences in the minor-element concentrations serve to characterize various aquifers, both in the Quaternary deposits and in the bedrock. All of the aquifers locally yield waters having statistically anomalous concentrations of uranium or radon, but these anomalies are spatially coincident only in a few places and particularly in three geologic environments considered favorable for uranium mineralization. These include the following: (1) Thomson Formation near the unconformably overlying Fond du Lac Formation, (2) Hinckley Sandstone near a major fault system, and (3) Denham Formation near the unconformity with the McGrath Gneiss, particularly where these rocks are faulted and overlain by the Fond du Lac Formation. One additional uranium environment characterized by thin laminae of uraniferous apatite was located in the Thomson Formation during outcrop reconnaissance and sampling. The coincidence of this and other anomalously high uranium values in the bedrock with specific uranium and radon anomalies in the groundwater confirms the usefulness of the hydrogeochemical data to uranium exploration in this glaciated terrane

On the anomalous concentrations of uranium in sediments from hydrothermal mounds. A geochemical roll-type mechanism

International Nuclear Information System (INIS)

Bernat, M.; Benhassaine, A.

1987-01-01

Sediments close to the nontronite formations of hydrothermal mounds often show anomalously high concentrations of uranium. This is frequently interpreted as being due to seeping of low temperature U bearing hydrothermal water through the basal basalt and into the overlying sediments. But we think that this phenomenon is the consequence of leaching of the sediment by hydrothermal water initially depleted in uranium. The migration of U is favoured by the pH of these water which dissolve the iron oxides and hydroxides giving Fe +++ ions in solution. The location and strength of the formed U anomalies are controlled by geochemical and hydrodynamicals factors. 22 refs [fr

Geochemical reconnaissance for uranium in the Palmyrides region of central Syria

International Nuclear Information System (INIS)

Jubeli, Y.M.

1990-01-01

An account is given of the application of multielement reconnaissance rock chemistry, coupled with ground scintillation γ-ray measurements, to the investigation of the dispersion patterns of uranium and other major and trace elements in the rocks of the arid Palmyrides region of central Syria. The region is underlain by 10 km of sediments that accumulated in an interplatform depression during the Mesozoic and Caenozoic. Uranium and associated elements were syngenetically incorporated into the Upper Cretaceous and Lower Palaeogene sediments - especially phosphorites, which are well represented in the region. The oxidizing environment of the region has facilitated the subsequent geochemical redistribution of uranium. In the investigation more than 400 lithogeochemical samples collected from an area of approximately 9000 km 2 were analysed for over 30 elements. The resulting data were interpreted with the aid of univariate and multivariate statistical methods and the areal distribution of uranium, its associated elements, multivariate geochemical functions and factor scores were mapped with the use of computer graphics. Anomalies of U are accompanied by concentrations of As, Se, V, Mo, Zn, Cd, Cu, Ni and P in various combinations. The highest U concentrations are found in the Upper Cretaceous, which contains a high proportion of phosphatic rocks; younger sediments contain progressively less U. Uranium anomalies close to faults, which have provided conduits for wider U migration, are superimposed on this pattern. Lithogeochemical methods thus define geochemical dispersion patterns with good contrast and delineate areas for further investigation. (author)

Preliminary study of the uranium mineralization in the Eastern Belt, San Ramon, Oxapampa

International Nuclear Information System (INIS)

Valencia, Jacinto

2013-01-01

Permotriasic intrusive magmatic rocks of the eastern belt, consisting of San Ramon and Oxapampa granites, have a good favorability as fertile uranium rocks, one facie of red granite called monzo-granite; this condition is the result of the execution the cooperation project IPEN IAEA PER 2/16, ‘Improving the uranium potential of Peru’. The field work consisted of geological and radiometric review, with sampling of outcrop intrusive. The field radiometry and chemical analysis of the rock samples indicate the presence of radiometric and uranium anomalies, the petro-mineragraphyc study identified the presence of uranium ore, a phosphate hydrated uranium and copper, torbernite type, secondary mineral formed from leaching of primary uranium minerals in granite, the mineralization is found both in the granite and sedimentary rock contact. (author).

Uranium geochemical exploration in northwestern Luzon

International Nuclear Information System (INIS)

Santos, G. Jr.; Fernandez, L.; Ogena, M.; Tauli, G.

1980-01-01

A reconnaissance geochemical stream water and sediment survey which was conducted in northwestern Luzon was able to detect ten (10) uranium anomalous areas. These anomalous areas are located along a north-south trending zone of Miocene marine clastics and sedimentary rocks with tuffaceous sediment intercalations. In general, northwest Luzon has low radioactivity except for two anomalous areas which have 3 to 6 times background radioactivity. Radon anomalies occur in sparsely scattered locations. The anomalous zones appear to be related to major north-south faults and secondary northeast-southwest trending structures. Geochemical correlations between uranium and other elements such as copper, lead, zinc, manganese, silver, cobalt and nickel are generally very poor. (author)

Moving to world's best uranium address

International Nuclear Information System (INIS)

Noakes, Frank

2006-01-01

Most exploration dollars spent in South Australia are focused on exploiting uranium. This is for good reason as South Australia is the world's best address for uranium. Pressure to cut CO 2 emissions and the ballistic growth of the Chinese and Indian economies has heightened expectations that the worldwide use of uranium for power generation will mushroom beyond its current 17% market share. The recent Australia-China deal only seems to confirm this; hence uranium's growing popularity among miners and explorers. Such is the attractiveness of uranium-related floats, when Toro Energy sought $18m in March it was swamped with more than three times share application volume. In the north west, Southern Gold and Hindmarsh Resources are expectantly drilling for commercial uranium deposits all around the acreage that hosts the Challenger gold mine in the Gawler Craton. The first exploration drilling for uranium in quaternary-age river channels will take place in South Australia's far north in May. Red Metal says while older and deeper tertiary river channels in the area that host the Beverley uranium mine were explored for uranium, the younger near-surface channel has not had a single hole drilled for uranium. This is despite the area being one of the 'hottest radiogenic terrains in South Australia'. The company will target calcrete-style uranium mineralisation similar to the Yerrlirrie deposit in Western Australia (52,000t U308). Tasman Resources will start drilling to test seven uranium targets within 30km of Olympic Dam, the world's largest known uranium deposit, later this year. Tasman also holds tenements adjoining the Warrior uranium deposit near Tarcoola that contains known radiometric anomalies within the 40km-long Wynbring paleochannels. They are the fourth largest uranium explorer in South Australia. Alliance Resources and its JV partner Quasar Resources are exploring the Beverley 4 Mile uranium prospect at Arkaroola. Quasar is an affiliate of Heathgate Resources

Uranium exploration in Australia

International Nuclear Information System (INIS)

Battey, G.C.; Hawkins, B.W.

1977-01-01

As a result of exploration which recommenced in 1966 Australia's uranium reserves increased from 6,200 tonnes in 1967 to 227,000 tonnes uranium by June 1976. Most discoveries in the early 1950's were made by prospectors. The increase in reserves during the past decade is the result of exploration by companies utilising improved technology in areas selected as geologically favourable. These reserves were established at relatively low cost. In the Alligator Rivers Uranium Province the ''vein'' type deposits at Jabiluka, Ranger, Koongarra and Nabarlek contain 17% of the world's reserves. Most of these discoveries resulted from the investigation of airborne radiometric anomalies but cover over the prospective host rocks will necessitate the future use of costlier and more indirect exploration techniques. There was exploration for sandstone type uranium deposits in most of Australia's sedimentary basins. The greatest success was achieved in the Lake Frome Basin in South Australia. Other deposits were found in the Ngalia and Amadeus Basins in Central Australia and in the Westmoreland area, N.W. Queensland. A major uranium deposit was found in an unusual environment at Yeelirrie, Western Australia where carnotite occurs in a caliche and clay host which fills a shallow, ancient drainage channel. Although caliche occurrences are relatively widespread on the Precambrian shield no other economic deposit has been found. Recent discoveries in the Georgetown area of Queensland indicate the presence of another uranium province but it is too early to assess its potential. The ore occurs in clastic sediments at the base of a volcanic sequence overlying a Precambrian basement. Several companies which have established large uranium reserves have a number of additional attractive prospects. Exploration activity in Australia in 1975 was at a lower level than in previous years, but the potential for discovering further deposits is considered to be high

Current uranium activities in Pakistan

International Nuclear Information System (INIS)

Moghal, M.Y.

2001-01-01

The rocks of Siwaliks group in Pakistan, extending from Kashmir in the east through Potwar Plateau, Bannu Basin and Sulaiman range up to the Arabian Sea in the west have been extensively explored for uranium. The Dhok Pathan Formation, which is younger member of the middle Siwaliks has been aeroradiometrically surveyed and extensively prospected on foot. A large number of anomalies were encountered in Kashmir, Potwar Plateau, Bannu Basin and Sulaiman range. While exploratory work in Sulaiman range and Bannu Basin yielded a few workable deposits, none of the anomalous areas yielded an ore grade concentration in Potwar Plateau. As conventional exploration activities in Potwar Plateau did not yield any ore grade concentration therefore a resource potential evaluation programme through geological modeling was started under the guidance of an IAEA expert. The volcanic material found in the middle Siwaliks is considered to be the main source of uranium and siliceous cement in the sandstones. These findings have considerably increased uranium potential in Siwaliks. The tectonic deformation during and after the deposition of Siwaliks is considered to be the main reason for mobilization of uranium, while permeability barriers and upward movement of oil products may provide trappings for the mobilized uranium. Through this survey south western part of Potwar Plateau being relatively less deformed is considered to provide conducive environments for concentration of uranium. Low grade uranium concentrations have also been discovered in carbonatites in northern part of Pakistan. Preliminary exploration in Sallai Patti carbonatite through drilling supplemented by trenching, pitting and aditing, subsurface continuation of surface concentrations has been confirmed. The ore contains about 200 ppm of uranium and 3 to 4% phosphate in addition to magnetite, rare metals and rare earths. It has been demonstrated on laboratory/pilot scale that the concentrations of uranium and phosphate

National Uranium Resource Evaluation: Manhattan Quadrangle, Kansas

International Nuclear Information System (INIS)

Fair, C.L.; Smit, D.E.

1982-08-01

Surface reconnaissance and detailed subsurface studies were conducted in the Manhattan Quadrangle, Kansas, to evaluate uranium favorability using National Uranium Resource Evaluation criteria. These studies were designed in part to follow up airborne radiometric and hydrogeochemical and stream-sediment surveys. More than 600 well records were examined in the subsurface phase of the study. Results of these investigations indicate environments favorable for channel-controlled peneconcordant sandstone uranium deposits in Cretaceous rocks and for Wyoming roll-type deposits in Pennsylvanian sandstones. The Cretaceous sandstone environments exhibit such favorable characteristics as a bottom unconformity, high bed load, braided fluvial channels, large-scale cross-bedding, and one anomalous outcrop. The Pennsylvanian sandstone environments exhibit such favorable characteristics as arkosic cross-bedded sandstones, included pyrite and organic debris, interbedded shales, and gamma-ray log anomalies. Environments considered unfavorable for uranium deposits are limestone and dolomite environments, marine black shale environments, evaporative precipitate environments, and some fluvial sandstone environments. Environments considered unevaluated because not enough data were available include Precambrian plutonic, metamorphic, and sedimentary rocks, even though a large number of thin sections were available for study

Uranium hydrogeochemical and stream sediment reconnaissance of the Rawlins NTMS quadrangle, Wyoming

International Nuclear Information System (INIS)

Weaver, T.A.; Morris, W.A.; Trexler, P.K.

1978-04-01

During the spring and winter of 1976 and January and June of 1977, 570 natural water and 1281 waterborne sediment samples were collected from 1369 locations in the Rawlins, Wyoming, NTMS quadrangle. The samples obtained from this 18 700-km 2 area were analyzed at the Los Alamos Scientific Laboratory for total uranium. The uranium concentrations in waters ranged from less than the detectable limit of 0.2 parts per billion (ppB) to 448 ppB, with a mean value of 6 ppB. The concentrations in sediments ranged from 1.2 parts per million (ppM) to 60.4 ppM, with a mean value of 4.1 ppM. Based on simple statistical analyses of these data, arbitrary anomaly thresholds were set at 50 ppB for water samples and 9 ppM for sediment samples. Eleven water and 44 sediment samples were considered anomalous; 1 anomalous water and 25 anomalous sediments could be associated with four of the five major uranium occurrences in the quadrangle. Only the Ketchum Buttes area did not show up in the data. Twelve minor reported occurrences could not be identified by the data. Eleven anomalous samples (8 waters and 3 sediments) and 13 near-anomalous samples (10 waters and 3 sediments) outline a broad area in the northeast corner of the quadrangle (corresponding to the drainage area of the Medicine Bow River) where two airborne radiometric anomalies were discovered in an earlier study. This area, and perhaps others, may warrant further, more detailed geological, geophysical, and geochemical investigations

Present exploration status of the Lianshanguan uranium deposit, Northeast China

International Nuclear Information System (INIS)

Fei, Q.; Shaokang, H.

1980-01-01

During recent years surface radiometry has revealed a series of anomalies and uranium occurrences in the Lianshanguan region of Northeast China which are present in Proterozoic Formations. Several significant uranium occurrences were tested by trenching and core drilling which resulted in the discovery of the Lianshanguan uranium deposit in 1978. The ore bodies of economic significance are located at a depth of 38-250m. Potential reserves are 1000 tons of U 3 O 8 . The geological setting of the Lower Proterozoic Lianshanguan uranium deposit has a certain similarity to the Alligator Rivers Region, Northern Territory, Australia. However, the Lianshanguan deposit occurs in detrital formations (in the lower part of the Lower Proterozoic sequence), adjacent to a migmatitic zone; it is overlain by carbonate argillitic rocks. The discovery of the Lianshanguan deposit indicates a potential for further uranium discoveries in northeast China, where Proterozoic sequences are well developed. The Lianshanguan uranium deposit is located approximately 100km south of Shenyang at 40 0 59'N and 123 0 30'E

Case history of natural analogue research on sandstone type uranium occurrences, Japan

International Nuclear Information System (INIS)

Sakamaki, Y.; Kanai, Y.

1991-01-01

Previous fundamental studies on the ore genesis of uranium occurrences chiefly in Cenozoic sandstone formations in Japan, have been re-examined as the case history on natural analogue of radionuclides in high-level radioactive wastes (HLRW). Two principal mode of occurrences have been distinguished among Cenozoic uranium localities in Japan. In the Setouchi (Inland Sea) subregion, hot-spots are found in lacustrine to shallow sea facies of calm environment, corresponding to the first stage of formation of tectonic basins. As observed in Ningyo-toge and Tono area, stratabound ore bodies are generally arranged into paleo-channels. Another type of sporadic uranium indications are found within collapse basins in the 'Green-tuff' subregion, where intense volcanisms and block movements had been taken places throughout Middle miocene age. Well-developed fractures were to be favorable paths for uraniferous groundwater, as well as the suitable site for deposition of uranium. In both cases, the source material of uranium is granitic basement. Under oxidizing environment, uranium anomalies have been occasionally detected in surface- or fracture waters which passing through decomposed granite. In contrast to the behavior of uranium, one of the adequate analogues for mobile nuclides, thorium and REE are relatively immobile even under the same geologic and geochemical circumstances. In ore horizon, where reducing condition has still been kept, geochronological age of tetravalent uranium mineral is in concordance with the age of the host rock. Analysis of structural control shows that the principal factors for uranium concentration are the layout of redox front related to paleo-water tables. 234U/238U disequilibrium method has been proved to be the powerful tool for detecting mobility of uranium in the host rock throughout diagenesis and weathering process. The result of field and laboratory works on this is reported as an example. (author)

Stream sediment geochemical surveys for uranium

International Nuclear Information System (INIS)

Price, V.; Ferguson, R.B.

1979-01-01

Stream sediment is more universally available than ground and surface waters and comprises the bulk of NURE samples. Orientation studies conducted by the Savannah River Laboratory indicate that several mesh sizes can offer nearly equivalent information. Sediment is normally sieved in the field to pass a 420-micrometer screen (US Std. 40 mesh) and that portion of the dried sediment passing a 149-micrometer screen (US Std. 100 mesh) is recovered for analysis. Sampling densities usually vary with survey objectives and types of deposits anticipated. Principal geologic features that can be portrayed at a scale of 1:250,000, such as major tectonic units, plutons, and pegmatite districts, are readily defined using a sampling density of 1 site per 5 square miles (13 km 2 ). More detailed studies designed to define individual deposits require greater sampling density. Analyses for elements known to be associated with uranium in a particular mineral host may be used to estimate the relative proportion of uranium in several forms. For example, uranium may be associated with thorium and cerium in monazite, and with zirconium and hafnium in zircon. Readily leachable uranium may be adsorbed to trapped in oxide coatings on mineral particles. Soluble or mobile uranium may indicate an ore source, whereas uranium in monazite or zircon is not likely to be economically attractive. Various schemes may be used to estimate for form of uranium in a sample. Simple elemental ratios are a useful first approach. Multiple ratios and subtractive formulas empirically designed to account for the presence of particular minerals are more useful. Residuals calculated from computer-derived regression equations or factor scores appear to have the greatest potential for locating uranium anomalies

Preliminary analysis of rare earth in knowledge of uranium metallogeny in the granite from San Ramon-La Merced, Junin

International Nuclear Information System (INIS)

Valencia, Jacinto

2014-01-01

The study shows the petrogenesis of San Ramon granite by the interpretation of Rare Earth Elements (REE) analyzed from the metallogenic understanding of the presence of uranium. The preliminary results indicate that the intrusive has originated from a very distinct crustal magma source of per-aluminous alkaline composition; constituting the negative anomaly of Europium (Eu) element confirming the cortical origin of granite; accordingly, uranium mineralization represented by torbernite, from a source of per-aluminous alkaline composition. The REE help to establish a genetic relationship with granite, which was placed in the late stages of magmatism, while uranium has originated from the same granite by hydrothermal incipient process. SR-1.1 sample presents the largest partition of REE in the diagram and is related to the Th and U amounts in facie red granite. (author).

Notes on the geochemical survey for uranium in Mindoro Island, Philippines

International Nuclear Information System (INIS)

Santos, G. Jr.; Fernandez, L.G.; Villamater, D.T.; Seguis, J.E.; Ibe, M.G.

1981-03-01

Geochemical reconnaisance using stream sediment and heavy-mineral concentrates panned from coarse alluvium has been carried out in Mindoro Island, one of the oldest and diverse geologic terrains in the Philippines. A total of 135 selected sampling points situated near accessible areas along the periphery of the island were sampled. The samples were collected at a density of one sample per 53 sq. km. A set minus 80 mesh stream sediment fraction and heavy-mineral concentrates was obtained from each sampling point. Mobile or extractable and total uranium were determined. A large uranium anomaly was delineated over the Carboniferous Mindoro Metamorphics as well as in areas underlain by Early Tertiary sedimentary formations. Another group of anomalies were outlined in the southern part of the island underlain by Jurassic Mansalay Formation and Early to Middle Tertiary sedimentary rocks with associated limestone and coal measures. (author)

Automated electron microprobe identification of minerals in stream sediments for the national uranium resources evaluation program

International Nuclear Information System (INIS)

Mosley, W.C. Jr.

1979-01-01

Over 500 stream sediment particles have been analyzed. About 96% have been identified as distinct minerals. Most of the others appeared to be mixtures. Only zinc-bearing gahnite had to be analyzed further for positive identification. Monazite and zircon were the only minerals with concentrations of uranium significantly above the detection limit. The Frantz Isodynamic Magnetic Separator isolated the monazite into the 1.0 fraction. Monazite particles in anomalous sediments contained up to 3.7 wt % uranium. This uranium concentration is unusually high for monazite, which normally has about 0.5 wt % uranium, and may be the cause of the anomaly

International Uranium Resources Evaluation Project (IUREP) national favourability studies: Guatemala

International Nuclear Information System (INIS)

1977-08-01

Before 1959 a private individual (Mr. Rene Abularach) is reported to have made an airborne radiometric survey of the Sierra de las Minas and Sierra Madre Ranges. Although many anomalies were detected by this survey, none were verified in the ground survey followup, despite apparently adequate flight control. In 1968 a United Nations Special Fund Mineral Survey Project completed over 1,000 km of carborne radiometric survey with geiger counter readings at 500 m intervals. No anomalies were detected, but background radioactivity for several formations and geologic environments was established. In 1969 the Guatemalan government solicited the IAEA for technical assistance In conducting a preliminary uranium favorability study designed to formulate recommendations for a national radioactive ore prospecting program. A carborne radiometric survey was made of environments theoretically favorable for uranium deposition, with spot geological and radiometric examinations being .conducted in the more favorable areas. All Important mining regions of Guatemala except the leterites and the ultrabasics were visited. No evidence of a uranium province was observed 1n these field investigations and the recommendation was made that the government not embark on a more detailed national prospecting program at that time. At the time of completion of the IAEA-Guatemalan government (GOG) reconnaissance program in 1971, no uranium reserves or resources were known. More recent information on uranium occurrences and resources 1n Guatemala does not appear to be available. Information on more recent uranium reconnaissance than that undertaken during 1971 IAEA-GOG study is lacking. However, in more recent years the country's mineral potential has been generally evaluated with the aid of the UN and ICAITI (Central American Research Institute for Industry). Except for quarry materials, the state owns all minerals. The state has priority on purchase of any mineral production needed for the country

Anomaly-free models for flavour anomalies

Science.gov (United States)

Ellis, John; Fairbairn, Malcolm; Tunney, Patrick

2018-03-01

We explore the constraints imposed by the cancellation of triangle anomalies on models in which the flavour anomalies reported by LHCb and other experiments are due to an extra U(1)^' gauge boson Z^' . We assume universal and rational U(1)^' charges for the first two generations of left-handed quarks and of right-handed up-type quarks but allow different charges for their third-generation counterparts. If the right-handed charges vanish, cancellation of the triangle anomalies requires all the quark U(1)^' charges to vanish, if there are either no exotic fermions or there is only one Standard Model singlet dark matter (DM) fermion. There are non-trivial anomaly-free models with more than one such `dark' fermion, or with a single DM fermion if right-handed up-type quarks have non-zero U(1)^' charges. In some of the latter models the U(1)^' couplings of the first- and second-generation quarks all vanish, weakening the LHC Z^' constraint, and in some other models the DM particle has purely axial couplings, weakening the direct DM scattering constraint. We also consider models in which anomalies are cancelled via extra vector-like leptons, showing how the prospective LHC Z^' constraint may be weakened because the Z^' → μ ^+ μ ^- branching ratio is suppressed relative to other decay modes.

Preliminary study of uranium in Pennsylvanian and lower Permian strata in the Powder River Basin, Wyoming and Montana, and the Northern Great Plains

International Nuclear Information System (INIS)

Dunagan, J.F. Jr.; Kadish, K.A.

1977-11-01

Persistent and widespread radiometric anomalies occur in Pennsylvanian and Lower Permian strata in the subsurface of the northern Great Plains and the Powder River Basin. The primary host lithology of these anomalies is shale interbedded with sandstone, dolomite, and dolomitic sandstone. Samples from the project area indicate that uranium is responsible for some anomalies. In some samples there seems to be a correlation between high uranium content and high organic-carbon content, which possibly indicates that carbonaceous material acted as a trapping mechanism in some strata. The Pennsylvanian and Permian rocks studied are predominantly marine carbonates and clastics, but there are rocks of fluvial origin in the basal Pennsylvanian of Montana, North Dakota, and South Dakota and in the Pennsylvanian and Permian deposits on the east flank of the Laramie Mountains. Fine-grained clastic rocks that flank the Chadron arch in western Nebraska are possibly of continental origin. The trend of the Chadron arch approximately parallels the trend of radiometric anomalies in the subsurface Permian-Pennsylvanian section. Possible source areas for uranium in the sediments studied were pre-Pennsylvanian strata of the Canadian Shield and Precambrian igneous rocks of the Ancestral Rocky Mountains

Geological and environmental observations in the Sunchales Creek and Tonco River , Don Otto uranium mine, Salta Province

International Nuclear Information System (INIS)

Gorustovich, S.; Guidi, F.; Bárbaro, N.; Nievas, H.; Tomellini, G.

2013-01-01

Results of geological and environmental observations made by professionals of the Comisión Nacional de Energía Atómica (CNEA) down streams Don Otto uranium mine on the Sunchales creek, from Los Guanacos strait down to the Tonco river mouth, and from river mouth down to narrow pass named Salto Grande, are presented in this report. La Yesera, Las Curtiembres and Los Blanquitos Formations of the Pirgua Subgroup, and Lecho and Yacoraite Formations of the Balbuena Subgroup crops out in that area (Salta Group, Cretaceous- Middle Eocene). Water stream analyses have given uranium contents between 890 μg/L and 1,100 μg/L, and uranium in stream sediments between 4 μg/g and 14 μg/g; radimetric anomalias up to 1,500 c/s in discoloured facies of the Las Curtiembres Formation, and 2,000 c/s in dark pelitic sediments of the Yacoraite Formation. A new zone with uranium traces in Curtiembres Formation belonging to the Pirgua Subgroup has been identified in the Alemanía cretaceous basin, which is stratigraphically similar to Cajoncillo, Las Abritas and El Fraile deposits. Those traces in addition to the other ones localized in the upper third of the Yacoraite Formation would have been originated by the geochemical uranium anomalies in waters and stream sediments by uranium leaching of rocks. The geochemical uranium anomalies in water and sediments are not a consequence of the antropic activity of the uranium mining carried out in Don Otto mine (1961-1982). (authors) [es

Application of soil radon survey to searching for sandstone-type uranium deposit at western margin of Ordos basin

International Nuclear Information System (INIS)

Liu Hanbin; Yin Jinshuang; Cui Yonghui

2006-01-01

On the basis of condition tests of soil radon survey at certain uranium deposit in Ordos basin, regional soil radon survey was carried but in a study area of western margin of Ordos basin. By processing of soil radon survey data, five anomalous areas with certain metallogenic potential have been delineated. Then, discovered anomalies have been interpreted and evaluated for providing important reference for further drilling work. Research results indicate that by soil radon survey, anomalies may be distinguished in a basin, and soil radon survey could be an important geochemical prospecting method for rapid evaluation of sandstone-type uranium deposit in basin areas. (authors)

Global gravitational anomalies

International Nuclear Information System (INIS)

Witten, E.

1985-01-01

A general formula for global gauge and gravitational anomalies is derived. It is used to show that the anomaly free supergravity and superstring theories in ten dimensions are all free of global anomalies that might have ruined their consistency. However, it is shown that global anomalies lead to some restrictions on allowed compactifications of these theories. For example, in the case of O(32) superstring theory, it is shown that a global anomaly related to π 7 (O(32)) leads to a Dirac-like quantization condition for the field strength of the antisymmetric tensor field. Related to global anomalies is the question of the number of fermion zero modes in an instanton field. It is argued that the relevant gravitational instantons are exotic spheres. It is shown that the number of fermion zero modes in an instanton field is always even in ten dimensional supergravity. (orig.)

Uranium resource assessment through statistical analysis of exploration geochemical and other data. Final report

International Nuclear Information System (INIS)

Koch, G.S. Jr.; Howarth, R.J.; Schuenemeyer, J.H.

1981-02-01

We have developed a procedure that can help quadrangle evaluators to systematically summarize and use hydrogeochemical and stream sediment reconnaissance (HSSR) and occurrence data. Although we have not provided an independent estimate of uranium endowment, we have devised a methodology that will provide this independent estimate when additional calibration is done by enlarging the study area. Our statistical model for evaluation (system EVAL) ranks uranium endowment for each quadrangle. Because using this model requires experience in geology, statistics, and data analysis, we have also devised a simplified model, presented in the package SURE, a System for Uranium Resource Evaluation. We have developed and tested these models for the four quadrangles in southern Colorado that comprise the study area; to investigate their generality, the models should be applied to other quandrangles. Once they are calibrated with accepted uranium endowments for several well-known quadrangles, the models can be used to give independent estimates for less-known quadrangles. The point-oriented models structure the objective comparison of the quandrangles on the bases of: (1) Anomalies (a) derived from stream sediments, (b) derived from waters (stream, well, pond, etc.), (2) Geology (a) source rocks, as defined by the evaluator, (b) host rocks, as defined by the evaluator, and (3) Aerial radiometric anomalies

Uranium recovery from slags of metallic uranium

International Nuclear Information System (INIS)

Fornarolo, F.; Frajndlich, E.U.C.; Durazzo, M.

2006-01-01

The Center of the Nuclear Fuel of the Institute of Nuclear Energy Research - IPEN finished the program of attainment of fuel development for research reactors the base of Uranium Scilicet (U 3 Si 2 ) from Hexafluoride of Uranium (UF 6 ) with enrichment 20% in weight of 235 U. In the process of attainment of the league of U 3 Si 2 we have as Uranium intermediate product the metallic one whose attainment generates a slag contend Uranium. The present work shows the results gotten in the process of recovery of Uranium in slags of calcined slags of Uranium metallic. Uranium the metallic one is unstable, pyrophoricity and extremely reactive, whereas the U 3 O 8 is a steady oxide of low chemical reactivity, what it justifies the process of calcination of slags of Uranium metallic. The calcination of the Uranium slag of the metallic one in oxygen presence reduces Uranium metallic the U 3 O 8 . Experiments had been developed varying it of acid for Uranium control and excess, nitric molar concentration gram with regard to the stoichiometric leaching reaction of temperature of the leaching process. The 96,0% income proves the viability of the recovery process of slags of Uranium metallic, adopting it previous calcination of these slags in nitric way with low acid concentration and low temperature of leaching. (author)

International Uranium Resources Evaluation Project (IUREP) orientation phase mission report: Venezuela. Draft

International Nuclear Information System (INIS)

Hetland, Donald L.; Obellianne, Jean-marie

1981-04-01

The IUREP Orientation Phase Mission to Venezuela believes that the Speculative Uranium Resources of that country fall between 2,000 and 42,000 tonnes. This assumes that a part of the Speculative Resources would be extracted as by-product uranium from wet-process phosphoric acid production. Past exploration in Venezuela has resulted in the discovery of very few uranium occurrences and radioactive anomalies except for the many airborne anomalies recorded on the Guayana Shield. To date no economic deposits or significant uranium occurrences have been found in Venezuela except for the uraniferous phosphorites in the Cretaceous Navey Formation which are very low grade. The uranium occurrences and radioactive anomalies can be divided according to host rock into: (1) Precambrian crystalline and sedimentary rocks, (2) Cretaceous phosphorite beds, (3) continental sandstone, and (4) granitic rocks. The greatest geological potential for further uranium resources is believed to exist in the crystalline and sedimentary Precambrian rocks of the Guayana Shield, but favorable geological potential also exist in younger continental sandstones. Since the Guayana Shield is the most promising for the discovery of economic uranium deposits most of the proposed exploration effort is directed toward that area. Considerable time, effort and capital will be required however, because of the severe logistical problems of exploration in this vast, rugged and inaccessable area, Meager exploration work done to date has been relatively negative suggesting the area is more of a thorium rather than a uranium province. However because of the possibility of several types of uranium deposits and because so little exploration work has been done, the Mission assigned a relatively small speculative potential to the area, i.e. 0 to 25,000 tonnes uranium. A small speculative potential (0 to 2,000 tonnes) was assigned to the El Baul area in Cojedes State, in the Llanos Province. This potential is postulated

Uranium Hydrogeochemical and Stream Sediment Reconnaissance in southwestern Montana

Energy Technology Data Exchange (ETDEWEB)

Broxton, D.E.

1978-02-01

The Los Alamos Scientific Laboratory conducted a Hydrogeochemical and Stream Sediment Reconnaissance in southwestern Montana from early August to mid-October of 1976. A total of 1240 water and 1933 sediment samples were collected from 1994 locations at a nominal density of one location per 10 km/sup 2/. The water samples were collected from streams, wells, and springs; sediment samples were taken at streams and springs. All samples were analyzed at Los Alamos for total uranium by fluorometry or delayed-neutron counting. The uranium content of water samples ranges from below the detection limit (less than 0.3 ppB) to 45.30 ppB and has a mean value of 1.40 ppB. The uranium content of the sediment samples ranges between 0.20 and 206.80 ppM and averages 6.12 ppM. The chosen uranium anomaly threshold value was 7 ppB for surface waters (streams), 9 ppB for groundwaters (wells and springs), and 25 ppM for all sediment samples. The study area consists of the following lithologic groups: Precambrian basement complex, Precambrian Belt metasediments, Paleozoic and Mesozoic shelf sediments, Cretaceous and early Tertiary volcanic and plutonic rocks, Laramide orogenic clastic sediments, and middle to late Tertiary volcanic rocks and intermontane basin sediments. Most of the anomalous water and sediment samples with well-developed dispersion trains occur in areas underlain by or adjacent to silicic plutonic rocks of the Idaho and Boulder batholiths. These anomalies may indicate the presence of uraniferous veins and pegmatites similar to those already known to exist in the area. Fewer anomalous water samples occur in areas underlain by Precambrian basement complex and Tertiary basin fill.

Uranium Hydrogeochemical and Stream Sediment Reconnaissance in southwestern Montana

International Nuclear Information System (INIS)

Broxton, D.E.

1978-02-01

The Los Alamos Scientific Laboratory conducted a Hydrogeochemical and Stream Sediment Reconnaissance in southwestern Montana from early August to mid-October of 1976. A total of 1240 water and 1933 sediment samples were collected from 1994 locations at a nominal density of one location per 10 km 2 . The water samples were collected from streams, wells, and springs; sediment samples were taken at streams and springs. All samples were analyzed at Los Alamos for total uranium by fluorometry or delayed-neutron counting. The uranium content of water samples ranges from below the detection limit (less than 0.3 ppB) to 45.30 ppB and has a mean value of 1.40 ppB. The uranium content of the sediment samples ranges between 0.20 and 206.80 ppM and averages 6.12 ppM. The chosen uranium anomaly threshold value was 7 ppB for surface waters (streams), 9 ppB for groundwaters (wells and springs), and 25 ppM for all sediment samples. The study area consists of the following lithologic groups: Precambrian basement complex, Precambrian Belt metasediments, Paleozoic and Mesozoic shelf sediments, Cretaceous and early Tertiary volcanic and plutonic rocks, Laramide orogenic clastic sediments, and middle to late Tertiary volcanic rocks and intermontane basin sediments. Most of the anomalous water and sediment samples with well-developed dispersion trains occur in areas underlain by or adjacent to silicic plutonic rocks of the Idaho and Boulder batholiths. These anomalies may indicate the presence of uraniferous veins and pegmatites similar to those already known to exist in the area. Fewer anomalous water samples occur in areas underlain by Precambrian basement complex and Tertiary basin fill

Geochemical drainage surveys for uranium: sampling and analytical methods based on trial surveys in Pennsylvania

International Nuclear Information System (INIS)

Rose, A.W.; Keith, M.L.; Suhr, N.H.

1976-01-01

Geochemical surveys near sandstone-type uranium prospects in northeastern and north-central Pennsylvania show that the deposits can be detected by carefully planned stream sediment surveys, but not by stream water surveys. Stream waters at single sites changed in U content by x10 to 50 during the 18 months of our studies, and even near known prospects, contain less than 0.2 ppB U most of the time. Uranium extractable from stream sediment by acetic acid--H 2 O 2 provides useful contrast between mineralized and nonmineralized drainages of a square mile or less; total U in sediment does not. High organic material results in increased U content of sediments and must be corrected. Changes in U content of sediment with time reach a maximum of x3 and appear to be of short duration. A sediment of about 200 mi 2 near Jim Thorpe detects anomalies extending over several square miles near known occurrences and a second anomaly about two miles northeast of Penn Haven Jct. A similar survey in Lycoming-Sullivan Counties shows anomalous zones near known prospects of the Beaver Lake area and northwest of Muncy Creek. As, Mn, Pb, and V are enriched in the mineralized zones, and perhaps in surrounding halo zones, but do not appear to be pathfinder elements useful for reconnaissance exploration

Uranium occurrence at Sao Teodosio farm, Currais Novos, Rio Grande do Norte, Brazil

International Nuclear Information System (INIS)

Favali, J.C.; Leal, J.R.L.V.

1974-01-01

The areas of certain radiometric anomalies discovered in Serido geosyncline were selected for intensive study because of the similarity of the geology to that of known uranium deposits in other parts of the world. The uranium mineralization at Sao Teodosio farm, near Currais Novos, RN, on the Serrinha anticline axis, occurs in alaskite similar to that at Rossing in Southwest Africa. The Rossing deposit is the best example of the model proposed by Armstrong (1974) as 'porphyry' uranium deposits. That uranium deposit presents low grade of uranium content, about 0,030% U 3 O 8 and hundred thousands tons of uranium oxide. At Sao Teodosio occurs 550 m.y. alaskitic pegmatitic granite and garnet-quartz-biotite-schists of Serido formation, Upper Precambrian. These older rocks are cut by diabases dykes of Upper Terciary age. Uranium mineralization is associated with pegmatitic granite bodies similar to dykes and sills. The most common uranium minerals are: uraninite, meta-autunite and uranophane. Oligoclase, microline and quartz are the most frequent minerals. Acessory minerals are magnetite, titanite and zircon. Uranium oxide content at Sao Teodosio is 0,023% and average thickness is 2,80 m [pt

Evolution of uranium distribution and speciation in mill tailings, COMINAK Mine, Niger.

Science.gov (United States)

Déjeant, Adrien; Galoisy, Laurence; Roy, Régis; Calas, Georges; Boekhout, Flora; Phrommavanh, Vannapha; Descostes, Michael

2016-03-01

This study investigated the evolution of uranium distribution and speciation in mill tailings from the COMINAK mine (Niger), in production since 1978. A multi-scale approach was used, which combined high resolution remote sensing imagery, ICP-MS bulk rock analyses, powder X-ray diffraction, Scanning Electron Microscopy, Focused Ion Beam--Transmission Electron Microscopy and X-ray Absorption Near Edge Spectroscopy. Mineralogical analyses showed that some ore minerals, including residual uraninite and coffinite, undergo alteration and dissolution during tailings storage. The migration of uranium and other contaminants depends on (i) the chemical stability of secondary phases and sorbed species (dissolution and desorption processes), and (ii) the mechanical transport of fine particles bearing these elements. Uranium is stabilized after formation of secondary uranyl sulfates and phosphates, and adsorbed complexes on mineral surfaces (e.g. clay minerals). In particular, the stock of insoluble uranyl phosphates increases with time, thus contributing to the long-term stabilization of uranium. At the surface, a sulfate-cemented duricrust is formed after evaporation of pore water. This duricrust limits water infiltration and dust aerial dispersion, though it is enriched in uranium and many other elements, because of pore water rising from underlying levels by capillary action. Satellite images provided a detailed description of the tailings pile over time and allow monitoring of the chronology of successive tailings deposits. Satellite images suggest that uranium anomalies that occur at deep levels in the pile are most likely former surface duricrusts that have been buried under more recent tailings. Copyright © 2015 Elsevier B.V. All rights reserved.

Aspects of uranium mineralization in the Beaufort West Karoo

Energy Technology Data Exchange (ETDEWEB)

Pretorius, L E

1977-01-01

The distribution and controlling factors of uranium mineralization in the sedimentary rocks of the Lower Beaufort Group have been investigated in the Beaufort West area between 22/sup 0/O' and 24/sup 0/O'E longitude and 32/sup 0/O' and 32/sup 0/45'S latitude. The mineralization is classified as 'primary' or 'secondary', depending on the time of emplacement and not on the oxidation state of the uranium minerals present. Petrographic and geochemical aspects of primary uranium deposition point to a syngenetic origin. Reconstruction of the paleodepositional environment suggests that the primary mineralization is restricted to paleo-pools or -meander cut-offs where stagnant reducing conditions existed. From geological mapping done to the south of Beaufort West it appears that this uranium mineralization is located in an 'intermediate' paleo-depositional zone between the true fluvial and delta front environments. The indications of secondary uranium distribution and epigenetic concentration in 'rolls' within the area were studied along with various other aspects of such mineralization. The permeability of the arenaceous rocks in the area seems to be too low to host large uranium deposits of this kind. Detail geochemical soil sampling suggests that Zn, P, Co and As could be used as pathfinder elements for uranium. Although regional anomalies were investigated no meaningful pattern could be developed.

Geology and uranium occurrences in the Forez tertiary plain (in the French 'Massif Central'); Geologie et mineralisations uraniferes de la plaine tertiaire du Forez (Massif Central francais)

Energy Technology Data Exchange (ETDEWEB)

Duclos, P [Commissariat a l' Energie Atomique, Fontenay-aux-Roses - 92 (France). Centre d' Etudes Nucleaires

1967-01-01

In the first part, the observations made during the geological survey of the Forez Tertiary plain (in the French 'Massif Central') are recalled. Then, using various methods, the author lists the formations according to chronology. Finally, a reconstitution of the geological history of this subsidence basin is attempted. In the second part, the occurrence of 17 uranium bearing geochemical anomalies is commented upon. Each of these various anomalies is given a place on the stratigraphic scale. This enables the author to put the successive phases of uranium deposition into their proper perspective in the history of the plain. In conclusion, the author points out the usefulness of these uraniferous geochemical anomalies. (author) [French] Dans la premiere partie, l'auteur rappelle les observations faites au cours de l'etude geologique de la plaine tertiaire du Forez (Massif Central francais). Puis se servant de differentes methodes, il etablit une chronologie des formations. Enfin, il termine par un essai de reconstitution de l'histoire geologique de ce bassin de subsidence. Dans la deuxieme partie, il commente la decouverte de 17 anomalies geochimiques uraniferes. Il situe ces differentes anomalies dans la serie stratigraphique. Ceci lui permet de replacer les depots successifs de l'uranium dans l'histoire de la plaine. Enfin, il indique l'interet de ces anomalies geochimiques uraniferes. (auteur)

Orientation geochemical survey for uranium exploration using 230Th

International Nuclear Information System (INIS)

Xia Dingliang.

1985-01-01

The distribution of 230 Th in soils, rocks and ores and its relationship with respect to uranium ore formation are discussed for its possible use in geochemical exploration for U. 230 Th, U and Ra, being members of the same decay series, are different in their geochemical behavior upon which the study is orientated. Twenty uranium deposits and occurrences located in western and southern Hunan province are tested. Geochemical data obtained are comprehensively correlated. It is suggested that 230 Th is useful not only in U-Ra disequilibrium study but also in understanding the geochemical evolution of U ores. The data aid to interpret the genesis of uranium deposits and to assess the radioactive anomalies and uranium-bearing zones. Therefore, it can be adopted as a tool for searching in deep-buried uranium ores. The field procedure is rather simple and flexible to meet any geological environment. It is easy to read out and is less influnced by any kind of interference. In case of disequilibrium caused by oxidation and reduction during the period of ore formation it still gives good indication compared with that of radiometry, radonmetry and geochemical sampling for U

National Uranium Resource Evaluation Program. Hydrogeochemical and stream sediment reconnaissance basic data for Beeville NTMS Quadrangle, Texas. Uranium resource evaluation project

Energy Technology Data Exchange (ETDEWEB)

1979-10-31

Results of a reconnaissance geochemical survey of the Beeville Quadrangle, Texas are reported. Field and laboratory data are presented for 373 groundwater and 364 stream sediment samples. Statistical and areal distributions of uranium and possible uranium-related variables are displayed. A generalized geologic map of the survey area is provided, and pertinent geologic factors which may be of significance in evaluating the potential for uranium mineralization are briefly discussed. The groundwater data indicate that the northwestern corner of the quadrangle is the most favorable for potential uranium mineralization. Favorability is indicated by high uranium concentrations; high arsenic, molybdenum, and vanadium concentrations; and proximity and similar geologic setting to the mines of the Karnes County mining district. Other areas that appear favorable are an area in Bee and Refugio Counties and the northeastern part of the quadrangle. Both areas have water chemistry similar to the Karnes County area, but the northeastern area does not have high concentrations of pathfinder elements. The stream sediment data indicate that the northeastern corner of the quadrangle is the most favorable for potential mineralization, but agricultural practices and mineralogy of the outcropping Beaumont Formation may indicate a false anomaly. The northwestern corner of the quadrangle is considered favorable because of its proximity to the known uranium deposits, but the data do not seem to support this.

National Uranium Resource Evaluation Program. Hydrogeochemical and stream sediment reconnaissance basic data for Beeville NTMS Quadrangle, Texas. Uranium resource evaluation project

International Nuclear Information System (INIS)

1979-01-01

Results of a reconnaissance geochemical survey of the Beeville Quadrangle, Texas are reported. Field and laboratory data are presented for 373 groundwater and 364 stream sediment samples. Statistical and areal distributions of uranium and possible uranium-related variables are displayed. A generalized geologic map of the survey area is provided, and pertinent geologic factors which may be of significance in evaluating the potential for uranium mineralization are briefly discussed. The groundwater data indicate that the northwestern corner of the quadrangle is the most favorable for potential uranium mineralization. Favorability is indicated by high uranium concentrations; high arsenic, molybdenum, and vanadium concentrations; and proximity and similar geologic setting to the mines of the Karnes County mining district. Other areas that appear favorable are an area in Bee and Refugio Counties and the northeastern part of the quadrangle. Both areas have water chemistry similar to the Karnes County area, but the northeastern area does not have high concentrations of pathfinder elements. The stream sediment data indicate that the northeastern corner of the quadrangle is the most favorable for potential mineralization, but agricultural practices and mineralogy of the outcropping Beaumont Formation may indicate a false anomaly. The northwestern corner of the quadrangle is considered favorable because of its proximity to the known uranium deposits, but the data do not seem to support this

National Uranium Resource Evaluation Program. Hydrogeochemical and stream sediment pilot survey of Llano area, Texas

International Nuclear Information System (INIS)

Nichols, C.E.; Kane, V.E.; Minkin, S.C.; Cagle, G.W.

1976-01-01

A pilot geochemical survey of the Llano, Texas, area was conducted during February and March 1976. The purpose of this work was to prepare for a subsequent reconnaissance geochemical survey of uranium in Central Texas. Stream sediment, stream water, well water, and plant ash from five geologic areas were analyzed in the laboratory for approximately 25 parameters. Examples of anomalous values in stream sediment and stream water indicate the usefulness of both sample types in identifying anomalies at a regional reconnaissance-scale station spacing of approximately 5 km (3 mi). Groundwater samples, which generally best indicate the geochemistry of formations at depth in a survey of this type, represent another important tool in detecting uranium mineralization. Anomalies in San Saba County are associated with the Marble Falls-Smithwich Formations and the Strawn Series (Pennsylvanian), the Houy Formation (Devonian and lower Mississippian), and the Hickory Sandstone Member of the Riley Formation (Cambrian). In Burnet County anomalous values are due to the influence of the Valley Spring Formation (Precambrian); and in Blanco County anomalies are found associated with the Riley Formation

National uranium resource evaluation. Raton Quadrangle New Mexico and Colorado. Final report

International Nuclear Information System (INIS)

Reid, B.E.; Griswold, G.B.; Jacobsen, L.C.; Lessard, R.H.

1980-12-01

Using National Uranium Resource Evaluation criteria, the Raton Quadrangle (New Mexico and Colorado) contains one environment favorable for uranium deposits, the permeable arkosic sandstone members of the Pennsylvanian-Permian Sangre de Cristo Formation for either peneconcordant or roll-type deposits. The favorable parts of the Sangre de Cristo lie mostly in the subsurface in the Raton and Las Vegas Basins in the eastern part of the quadrangle. An area in the Costilla Peak Massif was investigated for uranium by determining geochemical anomalies in stream sediments and spring waters. Further work will be required to determine plutonic environment type. Environments unfavorable for uranium deposits include the Ogallala, Raton, and Vermejo Formations, the Trinidad Sandstone, the Pierre Shale, the Colorado Group, the Dakota Sandstone, the Morrison Formation, the Entrada and Glorieta Sandstones, Mississippian and Pennsylvanian rocks, quartz-pebble conglomerates, pegmatities, and Tertiary granitic stocks

Geochemical characteristics of trace and rare earth elements in Xiangyangping uranium deposit of Guangxi

International Nuclear Information System (INIS)

Chen Qi; Xiao Jianjun; Fan Liting; Wen Cheng

2013-01-01

The trace and rare earth elements analysis were performed on two kinds ore-hosting rocks (Xiangcaoping granite and Douzhashan granite), alternated cataclastic granite and uranium ores in Xiangyangping uranium deposit of Guangxi. The results show that both of the two kinds granites display similar maturity features of highly evolved crust with the enrichment of Rb, Th, U, Ta and Pb, the depletion of Ba and Sr, high Rb/Sr and low Nb/Ta ratio, moderately rich light rare earth elements, strong negative Eu anomaly. Moreover, Douzhashan granite have higher Rb/Sr ratio and U content, which indicate it experienced more sufficient magma evolution and have higher potential of uranium source. There are almost no change in the content of trace and rare earth elements and distribution patterns during chloritization, hydromicazation and potash feldspathization of granite, but there occurred uranium enrichment and mineralization and REE remobilization while hematitization was superposed. This suggest that hematitization is most closely correlated with uranium mineralization in the working area. Because Most hematitization cataclastic rocks and uranium ore display similar geochemical characteristics to Douzhashan granite with relative high Rb/Sr and low Nb/Ta, Zr/Hf, ΣREE, LREE/HREE ration, and the trace and rare earth elements content and distribution patterns of some Xiangcaoping hematitization cataclastic rocks are between the two kinds of granite, therefore it can be concluded that the mineralization materials were mainly from Douzhashan granite and partly from Xiangcaoping granite. (authors)

Brief analysis on uranium metallogenic potential in Wunikeng area

International Nuclear Information System (INIS)

Wang Binghua

2010-01-01

Through the geological mapping, gamma total equivalent weight survey in Wunikeng area, the tectonics and gamma anomalies discovered in this area are analyzed, uranium metallogenic potential is analyzed by combining the regional metallogenic condition, contrasting the metallogenic geological background, massif condition, tectonic framework from these aspects of the regional geological background, massif condition on the work area, tectonic framework, etc.. (authors)

Radioactive equilibrium of uranium-bearing ores in some problems of applied geology

International Nuclear Information System (INIS)

Coulomb, R.; Girard, Ph.; Goldsztein, M.

1964-01-01

The state of equilibrium between several nuclides in radioactive relationship is determined with accuracy by the fundamental equations of radioactivity. It can be measured physically and expressed in suitable and internationally adopted units; Equilibrium - disequilibrium of uranium-bearing ores is a fairly complex phenomenon but the problem can be much simplified by well-chosen approximations in various practical field cases. The results of radiometric and radiochemical measurements lead to the interpretation of geochemical anomalies and may be used in the qualitative and quantitative estimation of uranium bearing deposits. (authors) [fr

Geochemical behaviour of uranium in the cycle of alteration

International Nuclear Information System (INIS)

Chervet, J.; Coulomb, R.

1958-01-01

The investigation of the genesis of secondary mineralized accumulations, and the prospecting of deposits from microchemical anomalies in the surface material, is requiring a well-developed knowledge of the geochemical properties of the uranium during the alteration phase. In the present work, the authors tried to track the uranium history during a part of his natural creeping. a) They describe some most typical mineralogical observations of alteration phenomena and material migration, picked up in place on the deposits. b) They give experimental results concerning the solubilities of the uranium minerals and the factors affecting this solubility. c) They study the water circulation in granitic batholites, and the influence of the occurrence of the uranium deposits on their composition. d) They observe the amplitude of phenomena restricting the dispersions: fixations, precipitations, etc., and the behaviour of growth in uraniferous areas. e) Finally, the opposition chemical alteration-radioactive equilibrium results in an important imbalance in altered materials. The authors tried to use the measurement of this imbalance to explain geochemical processes. (author) [fr

Preliminary research on finite difference method to solve radon field distribution over sandstone-type uranium ore body

International Nuclear Information System (INIS)

Li Bihong; Shuang Na; Liu Qingcheng

2006-01-01

The principle of finite difference method is introduced, and the radon field distribution over sandstone-type uranium deposit is narrated. The radon field distribution theory equation is established. To solve radon field distribution equation using finite difference algorithm is to provide the value computational method for forward calculation about radon field over sandstone-type uranium mine. Study on 2-D finite difference method on the center of either high anomaly radon fields in view of the character of radon field over sandstone-type uranium provide an algorithm for further research. (authors)

Estimation of the radiological background and dose assessment in areas with naturally occurring uranium geochemical anomalies—a case study in the Iberian Massif (Central Portugal)

International Nuclear Information System (INIS)

Pereira, A.J.S.C.; Neves, L.J.P.F.

2012-01-01

Naturally occurring uranium geochemical anomalies, representative of the several thousand recognized in the Portuguese section of the Iberian Massif and outcropping in three target areas with a total of a few thousand square metres, were subjected to a detailed study (1:1000 scale) to evaluate the radiological health-risk on the basis of a dose assessment. To reach this goal some radioactive isotopes from the uranium, thorium and potassium radioactive series were measured in 52 samples taken from different environmental compartments: soils, stream sediments, water, foodstuff (vegetables) and air; external radiation was also measured through a square grid of 10 × 10 m, with a total of 336 measurements. The results show that some radioisotopes have high activities in all the environmental compartments as well as a large variability, namely for those of the uranium decay chain, which is a common situation in the regional geological setting. Isotopic disequilibrium is also common and led to an enrichment of several isotopes in the different pathways, as is the case of 226 Ra; maximum values of 1.76 Bq L −1 (water), 986 Bq kg −1 (soils) and 18.9 Bq kg −1 (in a turnip sample) were measured. On the basis of a realistic scenario combined with the experimental data, the effective dose from exposure to ionizing radiation for two groups of the population (rural and urban) was calculated; the effective dose is variable between 8.0 and 9.5 mSv year −1 , which is 3–4 times higher than the world average. Thus, the radiological health-risk for these populations could be significant and the studied uranium anomalies must be taken into account in the assessment of the geochemical background. The estimated effective dose can also be used as typical of the background of the Beiras uranium metalogenetic province and therefore as a “benchmark” in the remediation of the old uranium mining sites. - Highlights: ► The importance of small-sized naturally occurring uranium

National Uranium Resource Evaluation: Providence Quadrangle, Connecticut, Rhode Island, and Massachusetts

International Nuclear Information System (INIS)

Zollinger, R.C.; Blauvelt, R.P.; Chew, R.T. III.

1982-09-01

The Providence Quadrangle, Connecticut, Rhode Island, and Massachusetts, was evaluated to a depth of 1500 m to identify environments and delineate areas favorable for uranium deposits. Criteria for this evaluation were developed by the National Uranium Resource Evaluation program. Environments were recognized after literature research, surface and subsurface geologic reconnaissance, and examination of known uranium occurrences and aeroradioactivity anomalies. Environments favorable for authigenic uranium deposits were found in the Quincy and Cowesett Granites. An environment favorable for contact-metasomatic deposits is in and around the borders of the Narragansett Pier Granite where it intrudes the Pennsylvanian sediments of the Narragansett Basin. An environment favorable for authigenic deposits in metamorphic rocks is in a migmatite on the eastern edge of the Scituate Granite Gneiss batholith. Environments favorable for contact-metasomatic deposits occur at the contacts between many of the granitic rocks and metamorphic rocks of the Blackstone Series. Results of this study also indicate environments favorable for sandstone-type uranium deposits are present in the rocks of the Narragansett Basin. Environments unfavorable for uranium deposits in the quadrangle include all granites not classified as favorable and the metamorphic rocks of eastern Connecticut. Glacial deposits and Cretaceous-Tertiary sediments remain unevaluated

MAGSAT anomaly map and continental drift

Science.gov (United States)

Lemouel, J. L. (Principal Investigator); Galdeano, A.; Ducruix, J.

1981-01-01

Anomaly maps of high quality are needed to display unambiguously the so called long wave length anomalies. The anomalies were analyzed in terms of continental drift and the nature of their sources is discussed. The map presented confirms the thinness of the oceanic magnetized layer. Continental magnetic anomalies are characterized by elongated structures generally of east-west trend. Paleomagnetic reconstruction shows that the anomalies found in India, Australia, and Antarctic exhibit a fair consistency with the African anomalies. It is also shown that anomalies are locked under the continents and have a fixed geometry.

Geophysical and geochemical regional evaluation and geophysical model for uranium exploration in the western part of Yanliao region

International Nuclear Information System (INIS)

Liu Tengyao; Cui Huanmin; Chen Guoliang; Zhai Yugui

1992-01-01

The western part of Yanliao region is an important uranium metallogenic region. This paper summarizes the regional geophysical model for uranium exploration composed of prediction model for favourable area of mineralization and evaluation model for anomalies on the basis of aeromagnetic and aeroradiometric data interpretation and analysis of the data from carborane and ground gamma spectrometric survey, high accurate magnetic survey, VLF survey and α-collected film survey in mult-displiary research work. The prospective prediction for uranium metallogenesis in this region was also conducted

Geology and uranium occurrences in the Forez tertiary plain (in the French 'Massif Central'); Geologie et mineralisations uraniferes de la plaine tertiaire du Forez (Massif Central francais)

Energy Technology Data Exchange (ETDEWEB)

Duclos, P. [Commissariat a l' Energie Atomique, Fontenay-aux-Roses - 92 (France). Centre d' Etudes Nucleaires

1967-01-01

In the first part, the observations made during the geological survey of the Forez Tertiary plain (in the French 'Massif Central') are recalled. Then, using various methods, the author lists the formations according to chronology. Finally, a reconstitution of the geological history of this subsidence basin is attempted. In the second part, the occurrence of 17 uranium bearing geochemical anomalies is commented upon. Each of these various anomalies is given a place on the stratigraphic scale. This enables the author to put the successive phases of uranium deposition into their proper perspective in the history of the plain. In conclusion, the author points out the usefulness of these uraniferous geochemical anomalies. (author) [French] Dans la premiere partie, l'auteur rappelle les observations faites au cours de l'etude geologique de la plaine tertiaire du Forez (Massif Central francais). Puis se servant de differentes methodes, il etablit une chronologie des formations. Enfin, il termine par un essai de reconstitution de l'histoire geologique de ce bassin de subsidence. Dans la deuxieme partie, il commente la decouverte de 17 anomalies geochimiques uraniferes. Il situe ces differentes anomalies dans la serie stratigraphique. Ceci lui permet de replacer les depots successifs de l'uranium dans l'histoire de la plaine. Enfin, il indique l'interet de ces anomalies geochimiques uraniferes. (auteur)

Airborne gamma anomalies in the Elbe Valley near Koenigstein, Germany - Origin and variation with time

International Nuclear Information System (INIS)

Ruhrmann, G.; Schmeling, B.; Schauer, M.; Gatzweiler, R.

1997-01-01

In 1982, an airborne gamma spectrometer survey was undertaken by SDAG WISMUT which was directed at the detection of further uranium mineralization in Saxony and Thuringia. Anomalies outlined along the Elbe river near the existing Koenigstein uranium mine were attributed to one or a combination of the following causes: radioactive residues from uranium processing facilities located upstream, temporary accumulation of Rn-decay products attached to dust particles in the atmosphere at the time of the survey, and radioactive waters emerging from uraniferous rocks along tectonic structures. In 1994, WISMUT GmbH re-evaluated the survey to determine the need for implementing cleanup measures. Subsequent to the verification of the original airborne data, ground surveys were undertaken that included gamma spectrometry, percussion probing and river sediment sampling. The new results did not confirm the magnitude of most of the 1982 airborne anomalies. The general decline of the radioactivity pointed out by the 1994 ground measurements is interpreted to be a result of the partial erosion and dilution of radionuclides in fluvial sediments as well as burial by additional river sediments since. Additional anomalous copper and zinc concentrations are attributed to sources other than mining. The ground follow-up delineated a new anomalous zone that is caused by radionuclides discharged with treated process and mine water. It is the only area, which may require further investigations and possible remedial action. (author)

Investigation on distribution of paleo-channels and prospect of uranium metallogenesis in Erlian basin, inner mongolia

International Nuclear Information System (INIS)

Dong Tingkuan; Kang Xiuping

2001-01-01

According to the characteristics of paleo-channel sedimentary evolution in Erlian Basin, the authors investigate the geomorphological forms, regional hydrogeological conditions, the distribution of recent and paleo-stream channels and alluvial-proluvial fans, the hydrodynamic conditions of recharge-run off-discharge for phreatic water and interlayer ground water, as well as the spatial distribution of local discharge areas applying the satellite image analysis techniques. Guided by the theory of hydrogenetic uranium deposit, and using geological, geophysical, hydrogeological data and materials of uranium occurrences and anomalies obtained by previous researchers the environmental relation between the distribution of paleo-channels-alluvial proluvial fans and the dispersion-concentration of uranium are synthesized and analysed. As a result, 19 uranium metallogenic prospective areas are delineated, and the direction for further uranium prospecting is proposed

Synthesis on Biology and Uranium Mineralization of Rabau Hulu Sector Kalan, Kalimantan Barat

International Nuclear Information System (INIS)

Bambang-Soetopo; Retno-Witjahyanti; Yanu-Wusana

2004-01-01

The results of previous research on Rabau Hulu sector consist of geology, geophysics and drilling data show that the area prospect for finding U mineralization. Goal of this synthesis is to know geological and U mineralization of Rabau sector in order to develop further followup program. In general geology the area consists of biotite micro quartzite, muscovite micro quartzite, muscovite quartzite, leopard quartzite, horn fels and granite. The directions of stratification is NE-SW of the dipping is NW. Prominent fault is NE-SW sinistral fault, NNE-SSW and NW-SE dextral fault. Uranium mineralization as a uraninite fill in the space between minerals and fractures system ENE-WSW, its associated with pyrite, pyrrhotite, chalcopyrite, molybdenite, sphalerite, magnetite, tourmaline and quartz. With radiometric anomalies values are about 1.000-15.000 c/s. Uranium mineralization process is connected with the granite intrusion as the hydrothermal magnetic process. (author)

National Uranium Resource Evaluation: Greensboro Quadrangle, North Carolina and Virginia

International Nuclear Information System (INIS)

Dribus, J.R.; Hurley, B.W.; Lawton, D.E.; Lee, C.H.

1982-07-01

The Greensboro Quadrangle, North Carolina and Virginia, was evaluated to identify and delineate areas favorable for the occurrence of uranium deposits. General surface reconnaissance and geochemical sampling were carried out in all geologic environments within the quadrangle. Aerial radiometric and hydrogeochemical and stream-sediment reconnaissance data were analyzed, and ground-truth followup studies of anomalies were conducted. Detailed surface investigations, log and core studies, and a radon emanometry survey were conducted in selected environments. The results of this investigation suggest environments favorable for allogenic uranium deposits in metamorphic rocks adjacent to the intrusive margins of the Rolesville, Castalia, Redoak, and Shelton granite plutons, and sandstone-type deposits in the sediments of the Durham and Dan River Triassic basin systems. Environments in the quadrangle considered unfavorable for uranium deposits are pegmatites and metamorphic rocks and their included veins associated with fault and shear zones

International Uranium Resources Evaluation Project (IUREP) national favourability studies: Iraq

International Nuclear Information System (INIS)

1977-11-01

Iraq consists of a lowland trough lying between asymmetrical and very different upland massifs to the east, north and west and continuing southeastwards to the Persian Gulf. The region is one of crustal weakness and subsidence with relatively young plastic sedimentary rocks engulfed in downwarped, ancient, rigid and highly resistant blocks. Exploration in the 1954-55 period found some minor radioactive anomalies and very low uranium contents in limestones and phosphates. The results of an aerial radiometric survey in 1973-74 are not known to IAEA. Iraq has no reported uranium resources but there are several favourable formations which warrant a detailed survey. In view of the size of the country and the small amount of systematic exploration carried out up to the present time, the Speculative Potential is considered to lie in the 1,000 to 10,000 tonnes uranium category. (author)

International Uranium Resources Evaluation Project (IUREP) national favourability studies: United Arab Emirates

International Nuclear Information System (INIS)

1977-11-01

While most of the rocks in the United Arab Emirates are of sedimentary marine origin there are also some granites and metamorphic rock areas. It is understood that Hunting Geology and Geophysics Ltd were contracted in 1975 to carry out a mineral survey over 11,500 square kilometres utilising, among others, gamma-ray spectrometry. The results of this survey are not known. A report in 1974 of a large occurrence of uranium in Fujairah was later discredited but at least two radioactive anomalies are known in the country. The existence of granitic rocks and the appropriate conditions for calcareous duricrust formations may indicate some slight potential for uranium. The Speculative Potential may be in the 1000 to 10,000 tonnes uranium category. (author)

Radon measurements in soils of Lagoa Real Uranium Province, BA: preliminary results

International Nuclear Information System (INIS)

Alves, James V.; Rocha, Zildete; Fuzikawa, Kazuo; Neves, J.M. Correia; Matos, Evando C. de

2007-01-01

The Cachoeira U mine in the Lagoa Real Uranium Province is the sole uranium producing mine in Brazil today. The necessity to increase ore reserves in the area is a reality, making any exploration efforts worthwhile to reach this objective. An exploration method based on radon detection in soil gas using the AlphaGUARD PQ2000PRO equipment was tested on two radiometric anomalies (no. 31 and no. 35) in the neighborhood of the mine. The results obtained indicated the technique as a helpful method for exploration of buried radioactive deposits. The method can not only discriminate thoron from radon but as a consequence indicate the original emanation source as well, making the method still more valuable in the search for uranium deposits. (author)

International training course on uranium exploration

International Nuclear Information System (INIS)

Barretto, P.M.C.

1978-01-01

radiometric control of uranium ores, and the advantages and disadvantages of different methods. The second week was spent entirely on reconnaissance level sampling of stream sediment and surface water in an area of approximately 300 km 2 . About 900 stream sediments and water samples were collected during this period by 12 groups of participants, each group consisting of two trainees. Their work was supervised by three field instructors. The third week was used to carry out a detailed survey over areas with newly discovered uranium anomalies. The work included line cutting for sampling, measurement of radon-222 concentration in soil-gas, soil sampling, total counts and gamma-ray spectrometnc readings at more than 200 sites. Spring and stream water were also sampled for radon determination and heavy minerals were collected for uranium analysis. Mr Barretto is a member of the Nuclear Materials and Fuel Cycle Section, Division of Nuclear Power and Reactors. In the last week, a visit was made to Joseph Stephan Institute's reactor and analytical laboratory facilities in Ljubljana The participants also visited the Regional Computing Centre in Ljubljana, where they were introduced to various procedures of computer data processing of geochemical data and its interpretation. The last day of the training course was used in analysing the results of the reconnaissance and detailed exploration phases with the help of manually, as well as computer-drawn, maps. In addition to the above programme, informal lectures were given during the course of the field work and on several evenings. The planning of the survey was discussed every day before going to the field. Training course certificates were presented to the participants at the end of the course. All the proposed objectives were reached. The work accomplished reflected the genuine interest and enthusiasm of the heterogeneous group of participants in carrying out the various tasks. The atmosphere was that of close co-operation and

International Uranium Resources Evaluation Project (IUREP) orientation phase mission report: Turkey. September to November 1980

International Nuclear Information System (INIS)

Ziehr, H.; Komura, A.

1985-02-01

The IUREP Orientation Phase Mission to Turkey estimates the Speculative Resources of the country to lie between 21 000 and 55 000 tonnes uranium. Past exploration in Turkey, dating from 1953, has indicated a very high number of uranium occurrences and radioactive anomalies, but ore deposits of significant size and grade have not been found. Present reserves amount to 4 600 tonnes uranium which can be allocated to approximately 15 sandstone type deposits in Neogene continental sediments. Several hundreds of other occurrences and radioactive anomalies exist where ore reserves have not been delineated. The uranium occurrences and radioactive anomalies can be divided according to host rock into (a) crystalline massif and (b) Tertiary continental sediment. The greatest geological potential for further resources is estimated to exist in the above mentioned two geological terrains. The most favourable geological potential exists in Neogene continental sedimentary basins near the crystalline massifs. Because surface exploration in the known favourable areas such as the Koepruebasi Basin has been so systematic, extensive, and successful, it is improbable that additional surface work will have much effect in increasing the number of new radioactive anomalies or uranium occurrences detected at the surface in these areas. Surface survey work in these areas should be mainly designed to assist the understanding of structures at depth. Surface reconnaissance survey work is, however, required in other parts of the above mentioned two geological terrains in this country. Before starting such a reconnaissance survey in new areas, the Mission suggests that a careful and extensive library study be conducted in close co-operation with sedimentologists, petrologists, and remote sensing specialists. The Mission suggests that in the medium term, 8 to 10 years, some 85 - 110 million U.S. Dollars be spent on airborne and ground surveys, including geological, radiometric, geochemical, and

Bernabe Montano uranium deposit, Sandoval County

International Nuclear Information System (INIS)

Kozusko, R.G.; Saucier, A.E.

1980-01-01

Uranium mineralization was discovered on the Bernabe Montano Grant early in 1971. This old land grant, which is part of the Laguna Indian Reservation, is approximately 25 mile northwest of Albuquerque, New Mexico. About 2,000 holes have been drilled on this property to date, and an ore reserve of 10 to 20 million lbs of uranium oxide has been delineated in the Westwater Canyon Member of the Morrison Formation. The mineralization consists of multiple, stacked blankets of mineralized humate which appear to be localized in an area of slightly thicker and more laterally continuous sandstones. The blankets occur along a relatively straight mineral trend about a half mile wide and several miles in length. Holes drilled on-trend usually encounter gamma anomalies, whereas holes drilled off-trend are barren. The uranium is believed to have been carried through the Westwater Canyon Member by ground water that followed the palochannel systems shortly after burial in Late Jurassic time. This discovery once again confirms the trend-ore concept, and it probably represents the present eastern economic limit of the Grants mineral belt. The orebody is unusual because it occurs in a structurally deformed area called the Rio Puerco fault zone. The mineralization, which does not conform to a roll-front model, represents an important addition to the ore reserves of the Grants uranium region

Study of reactions between uranium-plutonium mixed oxide and uranium nitride and between uranium oxide and uranium nitride; Etude des reactions entre l`oxyde mixte d`uranium-plutonium et le nitrure d`uranium et entre l`oxyde d`uranium et le nitrure d`uranium

Energy Technology Data Exchange (ETDEWEB)

Lecraz, C

1993-06-11

A new type of combustible elements which is a mixture of uranium nitride and uranium-plutonium oxide could be used for Quick Neutrons Reactors. Three different studies have been made on the one hand on the reactions between uranium nitride (UN) and uranium-plutonium mixed oxide (U,Pu)O{sub 2}, on the other hand on these between UN and uranium oxide UO{sub 2}. They show a sizeable reaction between nitride and oxide for the studied temperatures range (1573 K to 1973 K). This reaction forms a oxynitride compound, MO{sub x} N{sub y} with M=U or M=(U,Pu), whose crystalline structure is similar to oxide`s. Solubility of nitride in both oxides is studied, as the reaction kinetics. (TEC). 32 refs., 48 figs., 22 tabs.

Uranium project in Cerro Largo south orientation

International Nuclear Information System (INIS)

Pradier, B.

1982-01-01

This study of orientation was realized with the purpose of recognizing the extension of the anomalies from a known source , and of being able to determine the choice of the places and the quality of the material to sampling to obtain an ideal response. We have chosen the introduction of this study in a place that offers a source in power of Uranium located accurately and that presents a sequence pedology that group the main types of soils

Uranium Resources Inventory at Jumbang III West Kalimantan Systematic Prospection

International Nuclear Information System (INIS)

Soetopo, B; Wusana Y; Paimin; Sudjiman, FX

1998-01-01

Systematic prospection at jumbang III sector, west kalimantan has been carried out for identifying characteristic occurrence of the U mineralization and inventorying U resources potential area. The investigation has been based on U indication discovered in the form of a radiometric anomaly outcrop as high as 9000c/s. The possibility the U occurrence potential at the investigated may be resulted from granitic magma intrusion which produced an allogeneic type of uranium controlled by tectonic force. The method of the investigation includes systematic geological mapping and the result of the investigation shows that the lithology at the area is metamorphic rocks, intruded by biotite granite and dyke biotite adamelite and kersantite. Geological structure is NE-SW N-S and ESE- WNW strike slip faults. The uranium mineralization includes uraninite associated with magnetite, ilmenite, pyrite, pyrhotite, molybdenite, chalcopyrite, rutile, tourmaline, and quarts by magmatic hydrothermal process of allogeneic type U. The total U content of rock area is 7,57-4197,67 ppm U potential of the estimation result is 187.920 ton reserve and 25.3812 ton metallic U

Uranium project in Cerro Largo south orientation[Geochemical prospection of Uranium in Uruguay]; Proyecto uranio: orientacion Cerro Largo Sur

Energy Technology Data Exchange (ETDEWEB)

Pradier, B

1982-07-01

This study of orientation was realized with the purpose of recognizing the extension of the anomalies from a known source , and of being able to determine the choice of the places and the quality of the material to sampling to obtain an ideal response. We have chosen the introduction of this study in a place that offers a source in power of Uranium located accurately and that presents a sequence pedology that group the main types of soils.

Study on Regional Geology and Uranium Mineralization of Schwaner Mountains West and Central Kalimantan

International Nuclear Information System (INIS)

Soepradto-Tjokrokardono; Djoko-Soetarno; MS; Liliek-Subiantoro; Retno-Witjahyati

2004-01-01

Uranium occurrences indication in Kalimantan has been discovered at metamorphic and granites rocks of Schwaner Mountains as the radioactivity and geochemical anomalies. A regional geology of Schwaner Mountains show a watershed of West and East Kalimantan consist of Pinoh metamorphic rocks that was intruded by tonalitic and granitic batholite. The goal of this study is to observe the mechanism of the Uranium occurrences related to the regional tectonic, metamorphic rocks, tonalite and granitic batholite. Permokarbonaferrous metamorphic rocks as the big masses of roof pendant within tonalite mass. The metamorphic rocks originally as the big masses of roof pendant within tonalite mass. The metamorphic rocks originally derived from sedimentary process that produce a high content of uranium as well as a fine grained volcanic material. This uranium is deposited within neritic facies. Those sediments have been metamorphosed by low grade Abukuma regional metamorphism at the condition about 540 o C and 2000 bar. In early Cretaceous Tonalite of Sep auk intruded the rock and both metamorphics and tonalites. Those rocks were intruded by Late Cretaceous alkalin granite of Sukadana. Those crystalline rocks overlaid by an unconformity-related Kampari and Tebidah Formations that including within Melawi Group of Tertiary age. Uranium mineralization as the centimetric-metric veins related to tectonic N 100 o -110 o E and N 50 o E lineaments. Uranium was interpreted as a volcanic sedimentary origin, than it re mobilized by low grade regional metamorphism process. This enuchment process was carried out by fluor, boron and other metalliferous mineral within hydrothermal solutions of Sukadana granite. (author)

Uranium hydrogeochemical and stream sediment reconnaissance of the Cheyenne NTMS Quadrangle, Wyoming

International Nuclear Information System (INIS)

Trexler, P.K.

1978-06-01

Between June 1976 and October 1977, 1138 water and 600 sediment samples were systematically collected from 1498 locations in the Cheyenne NTMS quadrangle of southeast Wyoming. The samples were analyzed for total uranium at the Los Alamos Scientific Laboratory. The uranium concentration in waters ranged from 0.01 to 296.30 parts per billion (ppB), with a median of 3.19 ppB and a mean of 8.34 ppB. The uranium in sediments ranged from 0.8 to 83.0 parts per million (ppM) with a median of 3.4 ppM and a mean of 4.5 ppM. Arbitrary anomaly thresholds were selected to isolate those water and sediment samples containing uranium concentrations above those of 98% of the population sampled. Using this procedure, 23 water samples above 54.50 ppB and 12 sediment samples above 14.0 ppM were considered anomalous. Several areas appear favorable for further investigation for possible uranium mineralization. High uranium concentrations were detected in waters from the northeast corner of the Cheyenne quadrangle. High uranium concentrations were detected in sediments from locations in the southern and central Laramie Mountains and along the southeast and east-central edges of the study area

Calc-sodic zoning in rocks from Lagoa Real uranium Province, state of Bahia, Brazil

International Nuclear Information System (INIS)

Raposo, C.; Matos, E.C. de; Brito, W. de

1984-01-01

Preliminary studies of the lithogeochemistry, carried out on various deposits from the Uranium Province of Lagoa Real, show that in relation to the complex and multiphased processes of metasomatism, the sodic metasomatites are younger and were superposed on the potassic metasomatites. Such metasomatites developed in zones of extended and rejuvenated faults, after the transformation of the gnaisses, granitic rocks, amphibolites and ferruginous quartzites into various tectonites (mylonites, blastomylonites and protomylonites). The calcic metasomatism, subsequent to those phases, took place during the course of tectonothermal reactivations marking the termination of the principal metasomatic processes which aftected the rocks of Lagoa Real. The uranium deposit 'Jazida Laranjeiras', centrally situated in the Uranium Province of Lagoa Real is the only deposit in which the uranium mineralization is not intimately associated with the calcic metasomatism. Here, the ratio Na 2 O/CaO in the albitites is in the vicinity of 7,5 whereas in the other deposits this ratio decreases to values of about 1,5. The authors suggest calcic zoning (in the post-albitite phase) along the sigmoidal structure which localizes the uranium deposits, with an increase of the CaO content in the extreme parts of the structure - deposit 'Jazida Cachoeira' in the north and anomaly No. 02/12 in the south. Also suggested is the vertical zoning of calcium, whereby the intensity of the metasomatic phenomenon is increased towards the hanging wall side of the mieral parcel. (Author) [pt

Hamiltonian Anomalies from Extended Field Theories

Science.gov (United States)

Monnier, Samuel

2015-09-01

We develop a proposal by Freed to see anomalous field theories as relative field theories, namely field theories taking value in a field theory in one dimension higher, the anomaly field theory. We show that when the anomaly field theory is extended down to codimension 2, familiar facts about Hamiltonian anomalies can be naturally recovered, such as the fact that the anomalous symmetry group admits only a projective representation on the Hilbert space, or that the latter is really an abelian bundle gerbe over the moduli space. We include in the discussion the case of non-invertible anomaly field theories, which is relevant to six-dimensional (2, 0) superconformal theories. In this case, we show that the Hamiltonian anomaly is characterized by a degree 2 non-abelian group cohomology class, associated to the non-abelian gerbe playing the role of the state space of the anomalous theory. We construct Dai-Freed theories, governing the anomalies of chiral fermionic theories, and Wess-Zumino theories, governing the anomalies of Wess-Zumino terms and self-dual field theories, as extended field theories down to codimension 2.

Holographic entanglement entropy and gravitational anomalies

NARCIS (Netherlands)

Castro, A.; Detournay, S.; Iqbal, N.; Perlmutter, E.

2014-01-01

We study entanglement entropy in two-dimensional conformal field theories with a gravitational anomaly. In theories with gravity duals, this anomaly is holographically represented by a gravitational Chern-Simons term in the bulk action. We show that the anomaly broadens the Ryu-Takayanagi minimal

High-temperature thermal conductivity of uranium chromite and uranium niobate

International Nuclear Information System (INIS)

Fedoseev, D.V.; Varshavskaya, I.G.; Lavrent'ev, A.V.; Oziraner, S.N.; Kuznetsova, D.G.

1979-01-01

The technique of determining thermal conductivity coefficient of uranium niobate and uranium chromite on heating with laser radiation is described. Determined is the coefficient of free-convective heat transfer (with provision for a conduction component) by means of a standard specimen. The thermal conductivity coefficients of uranium chromite and niobate were measured in the 1300-1700 K temperature range. The results are presented in a diagram form. It has been calculated, that the thermal conductivity coefficient for uranium niobate specimens is greater in comparison with uranium chromite specimens. The thermal conductivity coefficients of the materials mentioned depend on temperature very slightly. Thermal conductivity of the materials considerably depends on their porosity. The specimens under investigation were fabricated by the pressing method and had the following porosity: uranium chromite - 30 %, uranium niobate - 10 %. Calculation results show, that thermal conductivity of dense uranium chromite is higher than thermal conductivity of dense uranium niobate. The experimental error equals approximately 20 %, that is mainly due to the error of measuring the temperature equal to +-25 deg, with a micropyrometer

Exploration of Uranium. Report to the Government of the Eastern Republic of Uruguay; Prospeccion de uranio. Informe al gobierno de la Republica Oriental del Uruguay

Energy Technology Data Exchange (ETDEWEB)

Muset, J A [International Atomic Energy Agency, Vienna (Austria)

1979-07-01

The Government of Uruguay with IAEA assistance carried out the Uranium prospection project and the evolution of uraniferous minerals resources on this country soil. Several arrangement were did such as the recollection and analysis of the geologic material. The Uranium project began with radiometric anomalies and out crops.

Using EVT for Geological Anomaly Design and Its Application in Identifying Anomalies in Mining Areas

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Feilong Qin

2016-01-01

Full Text Available A geological anomaly is the basis of mineral deposit prediction. Through the study of the knowledge and characteristics of geological anomalies, the category of extreme value theory (EVT to which a geological anomaly belongs can be determined. Associating the principle of the EVT and ensuring the methods of the shape parameter and scale parameter for the generalized Pareto distribution (GPD, the methods to select the threshold of the GPD can be studied. This paper designs a new algorithm called the EVT model of geological anomaly. These study data on Cu and Au originate from 26 exploration lines of the Jiguanzui Cu-Au mining area in Hubei, China. The proposed EVT model of the geological anomaly is applied to identify anomalies in the Jiguanzui Cu-Au mining area. The results show that the model can effectively identify the geological anomaly region of Cu and Au. The anomaly region of Cu and Au is consistent with the range of ore bodies of actual engineering exploration. Therefore, the EVT model of the geological anomaly can effectively identify anomalies, and it has a high indicating function with respect to ore prospecting.

An integrated geological, geochemical, and geophysical investigation of uranium metallogenesis in selected granitic plutons of the Miramichi Anticlinorium, New Brunswick

International Nuclear Information System (INIS)

Hassan, H.H.; McAllister, A.L.

1992-01-01

Integrated geological, geochemical, and geophysical data for the post-tectonic granitic rocks of the North Pole, Burnthill, Dungarvon, Trout Brook, and Rocky Brook plutons and surrounding areas were examined to assess their potential for uranium mineralization. Geological, geochemical, and geophysical criteria that are thought to be useful guides for uranium exploration were also established for the host granites. The granitic plutons were emplaced discordantly, late in the tectonomagmatic sequence and at shallow depths within the metasedimentary rocks of the Miramichi Anticlinorium. Geochemically, the host granites are highly evolved (Si0 2 > 75 wt. %), peraluminous and have strong similarities with ilmenite-series 'S-type' and 'A-type' granitoids. Uranium occurrences are spatially and perhaps temporally associated with late-phase differentiates of the plutons where elevated levels of other lithophile elements such as Sn, W, Mo, and F were also detected. Geophysically, the granitic plutons are associated with distinctively high aeroradiometric eU, eTh, and K anomalies that coincide with strong negative Bouguer anomalies and low magnetic values. Conceptual models involving magmatic and hydrothermal processes have been adopted to explain the concentration of uranium and associated metals in the granitic plutons

Radioactivity and uranium potentialities of wadi hammad area, north eastern desert, Egypt. Vol. 3

Energy Technology Data Exchange (ETDEWEB)

Salman, A B; Shalaby, M H; Khamis, H A [Nuclear Material Authority, Cairo, (Egypt)

1996-03-01

Late proterozoic, pan-african rocks exposed at Wadi Hammad area are represented by metamorphosed and un metamorphosed sediments and volcanics in addition to different types of intensive rocks. Systematic radiometric survey is conducted at W.Hammad area in order to reveal the distribution of radioactivity and uranium potentialities. Statistical analysis of the field data collected indicate that, high level of {delta}-radioactivity is linked to the younger granites compared with the other rock types. The tree types of younger granites recorded in the area namely: porphyritic granites, biotite granites, and perthitic leucogranites differ among each other in their ground radioactivity. The increase in ground {delta}- radioactivity from the porphyritic to biotite granites to perthitic leucogranites corresponds to the increase in the uranium content of these granites. Four radioactive anomalies were discovered in the younger granites of the area of W.Hammad. The genetic relation between certain set of fractures and the distribution of {delta}- radioactivity in G. El Gulf granites indicates that the area of anomalous radioactivity are structurally controlled by joint sets trending N-S, NNE-SSW and NNW-SSE. The presence of intensive hematitization episyenitization, red and milky silica veins, aplites and pegmatite veins indicate the presence of hydrothermal activities along these fractures. It is worth to mention that, the presence of episyentizied zone associated with radioactive anomaly, represents a good indication for the possibility of hosting uranium deposits in deeper horizon. Moreover, the presence of high back-ground of magnetic uranium in the perthitic leucogranites increases studied the possibility of concentration of uranium by leaching from the granites. 12 figs., 1 tab.

Radioactivity and uranium potentialities of wadi hammad area, north eastern desert, Egypt. Vol. 3

International Nuclear Information System (INIS)

Salman, A.B.; Shalaby, M.H.; Khamis, H.A.

1996-01-01

Late proterozoic, pan-african rocks exposed at Wadi Hammad area are represented by metamorphosed and un metamorphosed sediments and volcanics in addition to different types of intensive rocks. Systematic radiometric survey is conducted at W.Hammad area in order to reveal the distribution of radioactivity and uranium potentialities. Statistical analysis of the field data collected indicate that, high level of δ-radioactivity is linked to the younger granites compared with the other rock types. The tree types of younger granites recorded in the area namely: porphyritic granites, biotite granites, and perthitic leucogranites differ among each other in their ground radioactivity. The increase in ground δ- radioactivity from the porphyritic to biotite granites to perthitic leucogranites corresponds to the increase in the uranium content of these granites. Four radioactive anomalies were discovered in the younger granites of the area of W.Hammad. The genetic relation between certain set of fractures and the distribution of δ- radioactivity in G. El Gulf granites indicates that the area of anomalous radioactivity are structurally controlled by joint sets trending N-S, NNE-SSW and NNW-SSE. The presence of intensive hematitization episyenitization, red and milky silica veins, aplites and pegmatite veins indicate the presence of hydrothermal activities along these fractures. It is worth to mention that, the presence of episyentizied zone associated with radioactive anomaly, represents a good indication for the possibility of hosting uranium deposits in deeper horizon. Moreover, the presence of high back-ground of magnetic uranium in the perthitic leucogranites increases studied the possibility of concentration of uranium by leaching from the granites. 12 figs., 1 tab

Uranium occurrences in the Gordonia and Kuruman districts

International Nuclear Information System (INIS)

Levin, M.

1978-11-01

This report highlights uranium occurrences discovered by the author in the Kuruman and Gordonia Districts. These discoveries are the result of follow-up work of the regional geological, hydrological and hydrochemical studies of the area, undertaken by the Geology Division of the Atomic Energy Board since 1974. A surficial uranium deposit was discovered on the farm Rus en Vrede in the Kuruman District, at the junction of a palaeo-river with the Kuruman River. Uranium occurs in carbonaceous diatomaceous earth, with surface samples assaying up to 308 ppm U 3 O 8 . As uranium is also present in calcrete 18 km south of this deposit, there is a distinct possibility that significant surficial deposits may occur under the Kalahari sand cover in this area. In the Gordonia District an interesting discovery was made on the farm Tsongnapan where four boreholes, drilled for water, intersected radioactive bands in the Dwyka Tillite Formation. These rocks, which outcrop in the northeast corner of the Tsongnapan, also proved to be radioactive. Some 35 km to the east of this occurrence, borehole logging indicated the existence of an anomalous zone near the base of the Dwyka. In some of these boreholes uranium anomalies were also found in the calcrete and gravel of the Kalahari Formation. It is evident, therefore, that the Gordonia District has the potential of becoming an economically important uranium province. A radiometric ground survey of one of the pans indicated that wind and water action is possibly responsible for the local dispersion and segregation of radioactive minerals [af

Reconnaissance of promising areas for sandstone type uranium deposits in the Urmia-Naqadeh-Mahabad basin, NW Iran

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Mohammad Reza Hezareh

2018-04-01

mineralization and the same as the 8th subbasin there are known deposits of orogenic gold mineralization. 10. Charkeh (104 Km2. The rock units have the NW to SE trend. The anomalies of Zn, Mo, Sn, V, Ni, Au, As and Pb are reported but there is no evidence of mineralization. 11. Sheikh Ebrahim (38 Km2. The anomalies of Mo, Au, As and Pb are reported. The integration of the different layers shows that the prospecting area is suitable for future exploration of blind deposits. Geophysical data was processed and revealed those areas which have data. They can be classified into 5 different classes based on U and Th concentrations. The Hydrogeological data consist of EC, pH, Eh, DO and salinity. And the temperature was measured at the field by Sension 156 multimeter and was sent for ICP-MS analysis to the AMDEL and Applied Geological Research Center (Karaj laboratories. Two samples were obtained from each well by Widel et al.’s (1998 method. One sample was analyzed for Ca2+، Mg2+، Na+، K+، CO32-، HCO3-، SO42-and Cl- and the other samples were analyzed for major and trace elements. At each basin charge, the discharge and the trend of underground water were defined. Results The results revealed that this basin contains alkaline magmatic rocks such as alkaline rhyolite and tuff which are situated in reduced shale and continental volcanic clastic rocks and can be the source of uranium at the study area. Besides these rocks, tuffaceous sandstone, metamorphose sandstone and young alluvial by the reduction condition can be the suitable hosts for mineralization. Based on geological, geochemical, hydrogeological and geophysical data, the western basin is suitable for sandstone type uranium deposit and also there is some evidence of mineralization.

Uranium prospecting; La prospection de l'uranium

Energy Technology Data Exchange (ETDEWEB)

Roubault, M [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

1955-07-01

This report is an instruction book for uranium prospecting. It appeals to private prospecting. As prospecting is now a scientific and technical research, it cannot be done without preliminary studies. First of all, general prospecting methods are given with a recall of fundamental geologic data and some general principles which are common with all type of prospecting. The peculiarities of uranium prospecting are also presented and in particular the radioactivity property of uranium as well as the special aspect of uranium ores and the aspect of neighbouring ores. In a third part, a description of the different uranium ores is given and separated in two different categories: primary and secondary ores, according to the place of transformation, deep or near the crust surface respectively. In the first category, the primary ores include pitchblende, thorianite and rare uranium oxides as euxenite and fergusonite for example. In the second category, the secondary ores contain autunite and chalcolite for example. An exhaustive presentation of the geiger-Mueller counter is given with the presentation of its different components, its functioning and utilization and its maintenance. The radioactivity interpretation method is showed as well as the elaboration of a topographic map of the measured radioactivity. A brief presentation of other detection methods than geiger-Mueller counters is given: the measurement of fluorescence and a chemical test using the fluorescence properties of uranium salts. Finally, the main characteristics of uranium deposits are discussed. (M.P.)

Investigation of Alaska's uranium potential. Part 1. Reconnaissance program, West-Central Alaska and Copper River basin. Part 2. Uranium and thorium in granitic and alkaline rocks in Western Alaska

International Nuclear Information System (INIS)

Eakins, G.R.; Jones, B.K.; Forbes, R.B.

1977-02-01

A 6-week reconnaissance program was conducted in west-central Alaska and in the Copper River basin--Chitina River valley area to aid in determining the uranium potential of the state. Division personnel also submitted samples from the Healy, Eagle, and Charley River quadrangles. Collected were 916 stream-sediment samples and 427 bedrock samples for uranium, thorium, and potassium oxide determinations, and 565 water samples for uranium analyses. A statistical analysis of the determinations was made using a computer at the University of Alaska. Thresholds, anomalies, and U:Th ratios were calculated for eight separate regions. Anomalous values of the U, Th, and K 2 O, and radiometric measurements are discussed. A combination of all uranium exploration techniques is needed to locate potential uranium deposits in Alaska. Correlations between aerial and ground radiometric surveys and geochemical surveys were often lacking, indicating that each method may or may not be effective, depending on local conditions. One hundred and eight rock samples were selected from traverses across five plutons in western Alaska and analyzed for uranium, thorium, and potassium. The highest uranium concentrations detected were 86 and 92 ppM from a mineralized dike intrusion zone in the Selawik Lake Complex. Analysis of individual plutons yields strong correlations between mineralogy and radioactivity. The mineralogical variable that correlates with uranium or thorium varies from one pluton to the next. Based on these correlations, mineralogical guidelines are offered for the selection of uranium enriched variants in four of the five plutons

Preliminary study of the uranium favorability of Malheur County, Oregon

International Nuclear Information System (INIS)

Erikson, E.H.

1977-11-01

A reconnaissance study of middle and upper Tertiary volcaniclastic sedimentary and silicic volcanic rocks in Malheur County, Oregon, indicates that, based upon the data available: (1) it is unlikely that sandstone-type uranium deposits exist in sedimentary rocks of north-central Malheur County; and (2) favorable uranium environments are more likely to exist in and adjacent to uraniferous silicic eruptive centers and plugs. Some rhyolites in the northern part of the county contain marginally anomalous uranium abundances (6 to 8 +- 2 ppM U 3 O 8 ), compared with similar rocks in southeastern Oregon. Available uranium from these rocks, as determined by nitric-acid leaching, approaches 50 to 75 percent of the total chemical U 3 O 8 present. One Pliocene rhyolite vitrophyre sample from Duck Butte in western Malheur County contains 9 +- 2 ppM U 3 O 8 . The uranium contents of these rhyolites approach those found in silicic plugs spatially related to uranium deposits in the Lakeview district, Oregon (Erikson and Curry, 1977). It is possible that undiscovered epithermal and (or) supergene uranium deposits may exist in favorable wall rocks subjacent to uraniferous silicic eruptive centers (Duck Butte), calderas (McDermitt caldera to the south and others identified in western Owyhee County, Idaho), and silicic plugs (as in the Lakeview district). With the exception of one small uranium anomaly found in unconsolidated sands in the Grassy Mountain Formation, the sedimentary rocks observed in the study area did not possess abnormal radioactivity or exhibit evidence of uranium mobility and enrichment. Carbonaceous trash is uncommon in these rocks. Gently dipping sandstone members of the Deer Butte Formation (upper Miocene) and local channel sands in the Grassy Mountain Formation (Pliocene) may have once been the most permeable rocks in the Tertiary section; but, there is no evidence to suggest that they were conduits for uranium-bearing solutions

Issues in uranium availability

International Nuclear Information System (INIS)

Schanz, J.J. Jr.; Adams, S.S.; Gordon, R.L.

1982-01-01

The purpose of this publication is to show the process by which information about uranium reserves and resources is developed, evaluated and used. The following three papers in this volume have been abstracted and indexed for the Energy Data Base: (1) uranium reserve and resource assessment; (2) exploration for uranium in the United States; (3) nuclear power, the uranium industry, and resource development

National Uranium Resource Evaluation: Hutchinson Quadrangle, Kansas

International Nuclear Information System (INIS)

Fair, C.L.; Smit, D.E.; Gundersen, J.N.

1982-08-01

Surface reconnaissance and detailed subsurface studies were done within the Hutchinson Quadrangle, Kansas, to evaluate uranium favorability in accordance with National Uranium Resource Evaluation criteria. These studies were designed in part to follow up prior airborne radiometric, hydrogeochemical, and stream-sediment surveys. Over 4305 well records were examined in the subsurface phase of this study. The results of these investigations indicate environments favorable for channel-controlled peneconcordant sandstone deposits in rocks of Cretaceous age and for Wyoming and Texas roll-type deposits in sandstones of Pennsylvanian age. The Cretaceous sandstone environments exhibit favorable characteristics such as a bottom unconformity; high bedload; braided, fluvial channels; large-scale cross-bedding; and an anomalous outcrop. The Pennsylvanian sandstone environments exhibit favorable characteristics such as arkosic cross-bedded sandstones, included pyrite and organic debris, interbedded shales, and gamma-ray log anomalies. Environments considered unfavorable for uranium deposits are limestone and dolomite environments, marine black shale environments, evaporative precipitate environments, and some fluvial sandstone environments. Environments considered unevaluated due to insufficient data include Precambrian plutonic, metamorphic, and sedimentary rocks, even though a large number of thin sections were available for study

222Rn levels in Kingsville, Texas, and vicinity near an in situ uranium mine

International Nuclear Information System (INIS)

McGehee, T.L.; Martino, M.R.; Harr, T.L.; Samudio, A.

1994-01-01

An investigation of the 222 Rn levels in ground water, soils, and indoor air has disclosed two 222 Rn ground-water anomalies in the Kingsville, Texas, area from uranium-enriched sandstones of the Evangeline aquifer. Indoor air 222 Rn levels were measured in summer 1991 (from undetectable to 3.2 pCi/l) and winter 1991-1992 (0.01 to 3.98 pCi/l) to determine seasonal extremes and risk to the public. Soil 222 Rn concentration maps ranging from undetectable to 75.4 pCi/l correlate to the low levels found in homes. Results of this study are based on analyses of 218 water samples, 52 in situ soil samples, and 104 indoor air samples. Water samples were injected into a scintillation mix (EPA/EERF-Manual-78-1) and analyzed by liquid scintillation techniques. Indoor air and soil samples were collected using passive charcoal canisters and analyzed by gamma-ray detection techniques (EPA 520/5-87-005). One ground-water 222 Rn anomaly lies near the permitted boundary of a large uranium deposit that is being mined. Private wells near the ore body yielded, 1,023 to 23,256 pCi/l at the well head. A second anomaly is located 2.5 mi (4 km) north of the uranium ore body near Naval Air Station, Kingsville. Private water wells in this area yielded 442 to 1,950 pCi/l 222 Rn at the well head. The radon anomalies are related to subsurface mineralization, which is one of the known natural geologic hazards of this area. Indoor air 222 Rn levels are well below the U.S. Environmental Protection Agency (US/EPA) action limit of 4 pCi/l. However, the high levels of 222 RN in ground water should be mitigated before entry into the home environment. High 222 Rn levels in ground water were reduced to background levels in household waters by use of a pre-introduction large-capacity holding tank

Uranium speciation in plants

International Nuclear Information System (INIS)

Guenther, A.; Bernhard, G.; Geipel, G.; Reich, T.; Rossberg, A.; Nitsche, H.

2003-01-01

Detailed knowledge of the nature of uranium complexes formed after the uptake by plants is an essential prerequisite to describe the migration behavior of uranium in the environment. This study focuses on the determination of uranium speciation after uptake of uranium by lupine plants. For the first time, time-resolved laser-induced fluorescence spectroscopy and X-ray absorption spectroscopy were used to determine the chemical speciation of uranium in plants. Differences were detected between the uranium speciation in the initial solution (hydroponic solution and pore water of soil) and inside the lupine plants. The oxidation state of uranium did not change and remained hexavalent after it was taken up by the lupine plants. The chemical speciation of uranium was identical in the roots, shoot axis, and leaves and was independent of the uranium speciation in the uptake solution. The results indicate that the uranium is predominantly bound as uranyl(VI) phosphate to the phosphoryl groups. Dandelions and lamb's lettuce showed uranium speciation identical to lupine plants. (orig.)

Interpretation of the phosphate showings found in Uruguay. Recommendations for a a working programme; Interpretacion de los indicios de fosfato encontrados en Uruguay: recomendaciones para un programa de trabajo

Energy Technology Data Exchange (ETDEWEB)

Slansky, M

1983-07-01

The radioactive anomalies put in evidence during the investigation of uranium and the mining inventory carried out in Uruguay, are due to rocks more or less strongly phosp hated of the top proterozoic and of the paleozoic. These anomalies drive to interrogating ourselves on the possibilities of existence of deposits of phosphates exploitable.

Anomalies and gravity

International Nuclear Information System (INIS)

Mielke, Eckehard W.

2006-01-01

Anomalies in Yang-Mills type gauge theories of gravity are reviewed. Particular attention is paid to the relation between the Dirac spin, the axial current j5 and the non-covariant gauge spin C. Using diagrammatic techniques, we show that only generalizations of the U(1)- Pontrjagin four-form F and F = dC arise in the chiral anomaly, even when coupled to gravity. Implications for Ashtekar's canonical approach to quantum gravity are discussed

Imaging the Formation of High-Energy Dispersion Anomalies in the Actinide UCoGa_{5}

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Tanmoy Das

2012-11-01

Full Text Available We use angle-resolved photoemission spectroscopy to image the emergence of substantial dispersion and spectral-weight anomalies in the electronic renormalization of the actinide compound UCoGa_{5} that was presumed to belong to a conventional Fermi-liquid family. Kinks or abrupt breaks in the slope of the quasiparticle dispersion are detected both at low (approximately 130 meV and high (approximately 1 eV binding energies below the Fermi energy, ruling out any significant contribution of phonons. We perform numerical calculations to demonstrate that the anomalies are adequately described by coupling between itinerant fermions and spin fluctuations arising from the particle-hole continuum of the spin-orbit-split 5f states of uranium. These anomalies resemble the “waterfall” phenomenon of the high-temperature copper-oxide superconductors, suggesting that spin fluctuations are a generic route toward multiform electronic phases in correlated materials as different as high-temperature superconductors and actinides.

Characteristics of Chongan ring structure and its controlling role on uranium mineralization

International Nuclear Information System (INIS)

Liu Linqing

2001-01-01

A large ring structure has been discovered in Chong'an region on the basis of geological interpretation of remote sensing images. The data acquired from analysis of regional geology and in-situ investigation indicate that the ring structure is initiated during caledonian and activated for several times afterwards; It displays the highest activity during Yanshanian. Under the effect of this structure, Gulou-Masha lenticular geological body was firmed, controlling the regional distribution of uranium mineralization and anomalies occur in forms of central and bilateral symmetry. The data indicate that it is prospective to prospect uranium deposit in this region; therefore, more work should be placed on the deep levels

Stream-sediment geochemical prospecting for uranium in the Paleozoic of the Belgian Ardennes

International Nuclear Information System (INIS)

Martin, H.; Lefin, J.P.; Dejonghe, L.; Henry, J.

1983-01-01

Orientation studies showed that a positive geochemical response for uranium in the Belgium Ardennes could be obtained with bank sampling, which consists of collecting colluvium and alluvium on both sides of the rivers. This necessitates a large sampling density of about one sample per km 2 (10 205 samples from an area of 11 000 km 2 ). Anomalies (> 3 ppm) are found that fall into three main areas each in a different geological setting: (1) at the periphery of the Cambro-Silurian Massif of Stavelot; (2) within the transition beds between the Visean and Namurian; and (3) in the lower Devonian of the central Ardennes. (Auth.)

Dental Anomalies: An Update

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Fatemeh Jahanimoghadam

2016-01-01

Full Text Available Dental anomalies are usual congenital malformation that can happen either as isolated findings or as a part of a syndrome. Developmental anomalies influencing the morphology exists in both deciduous and permanent dentition and shows different forms such as gemination, fusion, concrescence, dilaceration, dens evaginatus (DE, enamel pearls, taurodontism or peg-shaped laterals. All These anomalies have clinical significance concerning aesthetics, malocclusion and more necessary preparing of the development of dental decays and oral diseases. Through a search in PubMed, Google, Scopus and Medline, a total of eighty original research papers during 1928-2016 were found with the keywords such as dental anomaly, syndrome, tooth and hypodontia. One hundred review titles were identified, eighty reviews were retrieved that were finally included as being relevant and of sufficient quality. In this review, dental anomalies including gemination, fusion, concrescence, dilaceration, dens invaginatus, DE, taurodontism, enamel pearls, fluorosis, peg-shaped laterals, dentinal dysplasia, regional odontodysplasia and hypodontia are discussed. Diagnosing dental abnormality needs a thorough evaluation of the patient, involving a medical, dental, familial and clinical history. Clinical examination and radiographic evaluation and in some of the cases, specific laboratory tests are also needed. Developmental dental anomalies require careful examination and treatment planning. Where one anomaly is present, clinicians should suspect that other anomalies may also be present. Moreover, careful clinical and radiographical examination is required. Furthermore, more complex cases need multidisciplinary planning and treatment.

Classification of Uranium deposits

International Nuclear Information System (INIS)

Dahlkamp, F.J.

1978-01-01

A listing of the recognized types of uranium mineralization shows nineteen determinable types out of which only six can be classified as of economic significance at present: Oligomiitic quartz pebble conglomerates, sandstone types, calcretes, intra-intrusive types, hydrothermal veins, veinlike types. The different types can be genetically related to prevalent geological environments, i.e. 1. the primary uranium occurrences formed by endogenic processes, 2. the secondary derived from the primary by subsequent exogenic processes, 3. the tertiary occurrences are assumed to be formed by endogenic metamorphic processes, although little is known about the behaviour of the uranium during the metamorphosis and therefore the metallogenesis of this tertiary uranium generation is still vague. A metallotectonic-geochronologic correlation of the uranium deposits shows a distinct affinity of the uranium to certain geological epochs: The Upper Archean, Lower Proterozoic, the Hercynian and, in a less established stage, the Upper Proterozoic. (orig.) 891 HP/orig. 892 MKO [de

Anomalies of Nuclear Criticality, Revision 6

International Nuclear Information System (INIS)

Clayton, E.D.; Prichard, Andrew W.; Durst, Bonita E.; Erickson, David; Puigh, Raymond J.

2010-01-01

This report is revision 6 of the Anomalies of Nuclear Criticality. This report is required reading for the training of criticality professionals in many organizations both nationally and internationally. This report describes many different classes of nuclear criticality anomalies that are different than expected. An anomaly is defined as something not in keeping with expected notions of fitness and order, a departure from the regular arrangement or general rule. In reviewing the literature and experimental data on nuclear criticality and the conditions under which a fission chain reaction can be achieved, a number of anomalies have come to light. The actinide group is composed of the fourteen elements beginning with thorium, Atomic No. 90, and ending with lawrencium, Atomic No. 103. There are about 220 known actinide isotopes, most of which are believed capable of supporting neutron chain reactions. Although every element in the actinide group has at least one isotope believed capable of supporting a chain reaction, from a practical point of view regarding the time for chemical processing, only those nuclides with half-lives more than several weeks are of obvious concern in criticality safety. Forty-six of the nuclides are known to have half-lives greater than six weeks. The selection of six weeks is somewhat arbitrary. There may well be shorter-lived nuclides of concern in criticality safety. These 46 nuclides are identified in Figure 44. Of the 46 nuclides, 4 are known and 37 are believed to be capable of supporting chain reactions, and 5 are known or believed to not support a chain reaction. Figure 44 was constructed in the format used for the Chart of the Nuclides.(1) Figure 44 also shows the distinction between fissile and fissible nuclides. The actinides derive their name from actinium (Atomic No. 89) because they tend to maintain an actinium-like electron structure as the fourteen inner electrons are added to the 5f electron shell. Actually, electrons do

Novel geochemical techniques integrated in exploration for uranium deposits at depth

International Nuclear Information System (INIS)

Kyser, K.

2014-01-01

Mineral deposits are in fact geochemical anomalies, and as such their detection and assessment of their impact on the environment should be facilitated using geochemical techniques. Although geochemistry has been used directly in the discovery of uranium deposits and more indirectly in shaping deposit models, the novel applications of geochemistry and integration with other data can be more effective in formulating exploration and remediation strategies. Recent research on the use of geochemistry in detecting uranium deposits at depth include: (1) more effective integration of geochemical with geophysical data to refine targets, (2) revealing element distributions in and around deposits to adequately assess the total chemical environment associated with the deposit, (3) the use of element tracing using elemental concentrations and isotopic compositions in the near surface environment to detect specific components that have migrated to the surface from uranium deposits at depth, (4) understand the effects of both macro- and micro-environments on element mobility across the geosphere-biosphere interface to enhance exploration using select media for uranium at depth. Geophysical data used in exploration can identify areas of conductors where redox contrasts may host mineralization, structures that act to focus fluids during formation of the deposits and act as conduits for element migration to the surface, and contrasts in geology that are required for the deposits. However, precision of these data is greatly diminished with depth, but geochemical data from drill core or surface media can enhance target identification when integrated with geophysical data. Geochemical orientation surveys over known unconformity-related deposits at depth clearly identify mineralization 900m deep. Drill core near the deposit, clay-size fractions separated from soil horizons and vegetation over and far from the deposit record element migration from the deposit as radiogenic He, Rn and Pb

Uranium prospecting; La prospection de l'uranium

Energy Technology Data Exchange (ETDEWEB)

Roubault, M. [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

1955-07-01

This report is an instruction book for uranium prospecting. It appeals to private prospecting. As prospecting is now a scientific and technical research, it cannot be done without preliminary studies. First of all, general prospecting methods are given with a recall of fundamental geologic data and some general principles which are common with all type of prospecting. The peculiarities of uranium prospecting are also presented and in particular the radioactivity property of uranium as well as the special aspect of uranium ores and the aspect of neighbouring ores. In a third part, a description of the different uranium ores is given and separated in two different categories: primary and secondary ores, according to the place of transformation, deep or near the crust surface respectively. In the first category, the primary ores include pitchblende, thorianite and rare uranium oxides as euxenite and fergusonite for example. In the second category, the secondary ores contain autunite and chalcolite for example. An exhaustive presentation of the geiger-Mueller counter is given with the presentation of its different components, its functioning and utilization and its maintenance. The radioactivity interpretation method is showed as well as the elaboration of a topographic map of the measured radioactivity. A brief presentation of other detection methods than geiger-Mueller counters is given: the measurement of fluorescence and a chemical test using the fluorescence properties of uranium salts. Finally, the main characteristics of uranium deposits are discussed. (M.P.)

Isotopic characterization of uranium in soils of the Ipanema National Forest (FLONA-Ipanema); Caracterizacao isotopica de uranio em solos da Floresta Nacional de Ipanema (FLONA-Ipanema)

Energy Technology Data Exchange (ETDEWEB)

Silva, F.B.; Marques, F.H., E-mail: fernandobaliani@yahoo.com.br, E-mail: fernando_henrique06@hotmail.com [Laboratorio de Pocos de Caldas (LAPOC/CNEN-MG), Pocos de Caldas, MG (Brazil); Enzweiler, J.; Ladeira, F.S.B., E-mail: Jacinta@ige.unicamp.br, E-mail: fsbladeira@ige.unicamp.br [Universidade Estadual de Campinas (UNICAMP), Campinas, SP (Brazil). Instituto de Geociencias

2015-07-01

The National Forest of Ipanema (FLONA) is situated on a geological anomaly, known as 'Domo de Aracoiaba'. The soils of the area include Oxisols, Inceptsols and Alfisols. The amount of uranium and respective isotope activities in a soil depend on the parental rock and on the pedologic processes. The aim of this study was to investigate the activities for uranium isotopes ({sup 238}U, {sup 234}U, {sup 235}U) and the activity ratio (AR) {sup 234}U/ {sup 238}U or secular equilibrium for different soil types of the area collected at horizons A and B. The amount of uranium showed no significant differences for soils generated from alkaline intrusive rocks and sandstone, however, secular equilibrium was observed for Oxisol (RA = 1), while Inceptsol presented RA> 1 and the other soils, Alfisols, presented RA values <1. (author)

Bhima Basin, Karnataka, India uranium mineralisation in the Neoproterozoic

International Nuclear Information System (INIS)

Achar, K.K.; Pandit, S.A.; Natarajan, V.; Kumar, M.K.; Dwivedy, K.K.

2001-01-01

Based on the geological analogy of known uranium mineralisation in other Proterozoic basins of India, the Bhima basin in northern Karnataka, covering an area of 5200 sq km, was taken up for uranium exploration. An integrated approach involving exploration techniques such as terrain analysis using satellite imageries, jeep-borne radiation survey, regional hydrogeochemical sampling and ground radiometric surveys were used. In addition gamma-ray logging of borewells drilled for water have enabled delineation of subsurface mineralisation at Gogi. Uranium mineralisation is associated with: (1) altered phosphatic limestone along the cherty limestone-shale boundary as at Ukinal, (2) brecciated non-phosphatic limestone as at Gogi, and (3) basic enclaves in the basement granites, as at Gogi East. Uranium occurs essentially as adsorbed phase on limonite and absorbed in collophane in the phosphatic limestone as at Ukinal. Mineralisation at Gogi is characterised by intense fracturing and brecciation apparently related to E-W trending Kurlagere-Gogi fault and is essentially low temperature (c.200 deg. C) hydrothermal nature represented by coffinite (thin veins and globular aggregates) along with pitchblende, pyrite (both framboidal and euhedral), pyrrhotite, haematite and anatase. Mineralisation is both syngenetic - remobilised as in the phosphatic limestones (Ukinal) and epigenetic hydrothermal (Gogi). The spatial relation of the unconformity, basement faults, and uranium - bearing basic enclaves within the basement points to the importance of the unconformity as a surface for fluid transport and fixation in conducive hosts. Presence of labile uranium in the basement granites with significant groundwater anomalies (up to 309 ppb U) enhances such possibilities. (author)

Report on the geological-geochemical research carried out within the area of geochemical anomaly P7, Vathyrema, Drama Department

International Nuclear Information System (INIS)

Stavropoulos, Athanasios.

1982-08-01

The investigated area covering about 30 km 2 is situated in the crystalline massive of Rhodope (north of Drama deparment, E. Macedonia) where granitoids constitute its main petrological type. The geological-geochemical and radiometric investigations carried out so far in the area have localized a large number of places with high values of γ-radiation (1.000 - 15.000 c/s), as well as high concentrations of uranium (50-500 ppm). The uranium mineralization within the zone of oxidation is expressed by the uranium mineral autunite, accompanied by intensive hematitization-limonitization and chloritization-kaolinization, and additionally by small spots and veinlets of pyrite and galena. It seems that tectonic control exists on the uranium mineralization, since most of the anomalous concentrations of uranium are sitting along mylonite zones rich in chlorite and kaolin. There have been discerned seven more anomalous part areas which will have to be covered by geochemical stream sediment sampling (phase 3), as well as geological mapping (scale 1:5.000). The results from the research conducted within the concerned anomaly lead us to the conclusion that this area is very promising and possibilities of localization of uranium payable concentrations are very high. (N.Ch.)

Remote Sensing, Geology and Geochemistry on the GVIII Uranium Mineralization, Gabal Gattar, North Eastern Desert, Egypt

International Nuclear Information System (INIS)

Elkholy, D.M.; Elhusseiny, M.O.; Saleh, W.H.; Elzalaky, M.A.

2012-01-01

GVIII- uranium occurrence of Gabal Gattar is located at the intersection of Lat. 27° 05' 56 a nd Long. 33° 16' 33 t o the south of GH-uranium occurrence. This occurrence is hosted in the alkali feldspar granite of Gabal Gattar. It is dissected by NNE-SSW, ENE-WSW and NW-SE faults and fractures. The granite is strongly altered in the zones of these faults and fractures. This granite is composed of K-feldspars, quartz, plagioclase and biotite as essential minerals and zircon, apatite, fluorite as accessories. The secondary minerals are chlorite, sericite, muscovite and iron oxides. The main alterations along the fault and fracture zones are hematitization, silicification, kaolintiization, chloritization and fluoritization that increase at the zones of intersection.The Advanced Spacebome Thermal Emission and Reflection Radiometer (ASTER) discriminated and mapped the hematitized zones in the studied granitic rocks predicting iron oxides as pathfinder minerals that be helpful in localizing high uranium concentration. The compilated and integrated data as alteration zones, geological and structural features using Geographic Information System (GIS) played an important role in correlating, manipulating, visualizing and extracting the information getting a better result for interpretation and evaluation of this occurrence. The study granite is geochemically, alkali- feldspar granite to syenogranite originated from weakly peraluminous magma of alkaline affinity and of within plate tectonic setting due to crustal relaxation. This granite shows many geochemical characterestics similar to the A-type granite, high contents of SiO 2 , (Na 2 O + K 2 O), Rb, Nb, Y, low contents of MgO, CaO and Sr and apparently F-rich granite.Radiometric measurements of GVIII U-occurrence show that the study granite records uranium values between 15 and 28 ppm, while the anomalies record uranium values range from 400 to more than 30000 ppm. Surfacial yellow secondary uranium

Heavy mineral survey for uranium in the Philippines

International Nuclear Information System (INIS)

Tauchid, M.; Santos, G. Jr.; Hernandez, E.; Bernido, C.

1983-01-01

A reconnaissance geochemical survey for uranium was carried out in the island of Samar in the Philippines covering an area of about 13,000 km 2 . The survey represents the first practical demonstration in the country of the use of geochemical techniques to outline large possibly interesting areas within a short period and with modest monetary expenditure. The survey entailed the systematic collection of 1530 heavy mineral concentrates, stream sediments and water samples, and the measurement of radioactivity at 510 stations along the major drainage system of Samar. The average sampling density was 1/20-25 km 2 . All solid samples were analysed for U, Cu, Pb, Zn, Mn, Ag, Co and Ni. Uranium, radon, conductivity and pH were measured in most of the water samples collected. More than 9000 chemical determinations were made. Results of the survey clearly point to the usefulness of heavy mineral sampling at the low density level of observation. The non-magnetic fraction of the heavy mineral concentrates outlined strong and well defined areas of interest for most of the elements analysed. Stream sediment sampling at this sampling density indicated weaker, less clearly defined anomalies. Uranium and radon analyses performed on stream water samples and ground scintillometer readings provided invaluable complementary information relevant to the evaluation of the island's uranium potential. (author)

National uranium resource evaluation, Hot Springs Quadrangle, South Dakota and Nebraska

International Nuclear Information System (INIS)

Truesdell, D.B.; Daddazio, P.L.; Martin, T.S.

1982-06-01

The Hot Springs Quadrangle, South Dakota and Nebraska, was evaluated to a depth of 1500 m to identify environments and delineate areas favorable for the occurrence of uranium deposits. The evaluation used criteria developed by the National Uranium Resource Evaluation program. Surface reconnaissance was conducted using a portable scintillometer and a gamma spectrometer. Geochemical sampling was carried out in all geologic environments accessible within the quadrangle. Additional investigations included the followup of aerial radiometric and hydrogeochemical anomalies and a subsurface study. Environments favorable for sandstone-type deposits occur in the Inyan Kara Group and Chadron Member of the White River Group. Environments favorable for marine black-shale deposits occur in the Hayden Member of the Minnelusa Formation. A small area of the Harney Peak Granite is favorable for authigenic deposits. Environments considered unfavorable for uranium deposits are the Precambrian granitic and metasedimentary rocks and Paleozoic, Mesozoic, and Tertiary sedimentary rocks other than those previously mentioned

Hydrogeochemical and stream sediment sampling for uranium in the sandstone environment

International Nuclear Information System (INIS)

Wenrich, K.J.

1985-01-01

Sandstone terranes commonly host uranium occurrences in the western United States. In addition, because sedimentary terranes, particularly shales and immature, not well cemented sandstone, contribute more sediment and soluble material than do plutonic, volcanic, or metamorphic terranes they are an excellent regime for hydrogeochemical and stream-sediment prospecting. Because of higher conductivity, and hence higher uranium content, of waters draining such environments the sampling need not be as precise nor the analytical detection limit as low as in other terranes to yield a successful survey. Nevertheless, reasonable preparation and care of the samples is recommended: (1) The water samples should be filtered through 0.45 μm membranes and acidified to a pH of less than 1. (2) Because the adsorption of uranium by organic material is so significant it is recommended that the reasonable finest stream-sediment fraction, 4 , conductivity, etc.) are useful in the data reduction towards the elimination of false anomalies. (author)

Uranium geology of the eastern Baker Lake basin, District of Keewatin, Northwest Territories

International Nuclear Information System (INIS)

Miller, A.R.

1980-01-01

Proterozoic sequences associated with major unconformities are potential uranium metallogenic provinces. Late Aphebian to Paleohelikian Dubawnt Group contintental clastic sedimentary and subaerial alkaline volcanic rocks and underlying Archean gneisses, District of Keewatin, Northwest Territories, represent one such uraniferous metallogenic province. Three types of uranium mineralization are present in the eastern Baker Lake basin, which extends from Christopher Island at the eastern end of Baker Lake southwestwards to the western limit of Thirty Mile Lake. The three uranium associations are: 1) fracture controlled mineralization in the Dubawnt Group and basement gneisses (U-Cu-Ag-Au-Se or U-Cu-Pb-Mo-Zn), 2)diatreme breccia mineralization in basement gneisses (U-Cu-Zn), and 3) impregnation and microfracture mineralization in altered arkose peripheral to lamprophyre dykes(U-Cu-Ag). Hydrothermal fracture related mineralization is controlled by northwest- and east-northeast-trending fault-fracture zones. Diatreme breccia mineralization results from the channelling of groundwaters through highly permeable brecciated gneiss. Mineralization within the altered Kazan arkose peripheral to alkaline dyke complexes formed by a two stage process. Iron and copper sulphides and silver were deposited within the outer portions of the thermal aureole in response to a temperature and Eh gradient across a convective cell created by the thermal anomaly of the dyke complex. The epigenetic sulphide mineralization subsequently provided the reducing environment for precipitation of uranium from groundwater. All three uranium associations show a close spatial distribution to the basal Dubawnt unconformity. The lithological and structural relationships of the Dubawnt Group rocks, types of mineralization and associated alteration assemblages are strikingly similar to the Beaverlodge district, Saskatchewan. (author)

Case history of the discovery of the Jabiluka uranium deposits, East Alligator River region, Northern Territory of Australia

International Nuclear Information System (INIS)

Rowntree, J.C.; Mosher, D.V.

1976-01-01

Pancontinental Mining Limited acquired exploration rights over an area in the East Alligator River Region, Northern Territory, Australia, in 1970. Subsequently, Getty Oil Development Company Limited acquired a substantial minority interest in the property. The Jabiluka deposits were discovered during the course of exploration and are currently the largest of the four major uranium deposits in the East Alligator River Region. This region at present contains 24% of the western world's reasonably assured resources of uranium. The exploration techniques employed during primary and secondary exploration on the property between 1971 and 1975 and during the delineation of the Jabiluka deposits are discussed in detail. The case history illustrates the exploration philosophy which was successfully employed on the Jabiluka property. The philosophy encompasses the following points: The need for an assessment on the limits of airborne radiometric surveys; the necessity for detection and evaluation of point source anomalies; the necessity for exploration along extensions of favourable lithologies; and the desirability of modification of exploration techniques on different types of anomalies. Some aspects of this philosophy may be useful in exploration for similar stratabound uranium deposits in other areas. (author)

Geologic-radiometric techniques applied for uranium prospection at the Hierro-Cayo Largo area

International Nuclear Information System (INIS)

Gongora, L.E.; Olivera, J.

1995-01-01

Using geologic-radiometric techniques uraniferous anomalies were evaluated at the Hierro-Cayo Largo area located in Pinar del Rio province. During the uranium prospection works at most promising areas, geologic itineraries and gamma ray, radon emanation spectrometric survey were done. Trenches were made and some boreholes were drilled (up to 20-30 m depth). In addition a lot of samples were taken in order to determine the amount of U, Ra, Th, y K by spectrometric techniques. As result of this investigation, a geological placing, a mineralogical and geochemical characteristic of uraniferous mineralization was possible to find out. The appropriate prospection indications for uranium exploration at Esperanza geologic zone were defined

Uranium enrichment

International Nuclear Information System (INIS)

1989-01-01

GAO was asked to address several questions concerning a number of proposed uranium enrichment bills introduced during the 100th Congress. The bill would have restructured the Department of Energy's uranium enrichment program as a government corporation to allow it to compete more effectively in the domestic and international markets. Some of GAO's findings discussed are: uranium market experts believe and existing market models show that the proposed DOE purchase of a $750 million of uranium from domestic producers may not significantly increase production because of large producer-held inventories; excess uranium enrichment production capacity exists throughout the world; therefore, foreign producers are expected to compete heavily in the United States throughout the 1990s as utilities' contracts with DOE expire; and according to a 1988 agreement between DOE's Offices of Nuclear Energy and Defense Programs, enrichment decommissioning costs, estimated to total $3.6 billion for planning purposes, will be shared by the commercial enrichment program and the government

Uranium production from phosphates

International Nuclear Information System (INIS)

Ketzinel, Z.; Folkman, Y.

1979-05-01

According to estimates of the world's uranium consumption, exploitation of most rich sources is expected by the 1980's. Forecasts show that the rate of uranium consumption will increase towards the end of the century. It is therefore desirable to exploit poor sources not yet in use. In the near future, the most reasonable source for developing uranium is phosphate rock. Uranium reserves in phosphates are estimated at a few million tons. Production of uranium from phosphates is as a by-product of phosphate rock processing and phosphoric acid production; it will then be possible to save the costs incurred in crushing and dissolving the rock when calculating uranium production costs. Estimates show that the U.S. wastes about 3,000 tons of uranium per annum in phosphoric acid based fertilisers. Studies have also been carried out in France, Yugoslavia and India. In Israel, during the 1950's, a small plant was operated in Haifa by 'Chemical and Phosphates'. Uranium processes have also been developed by linking with the extraction processes at Arad. Currently there is almost no activity on this subject because there are no large phosphoric acid plants which would enable production to take place on a reasonable scale. Discussions are taking place about the installation of a plant for phosphoric acid production utilising the 'wet process', producing 200 to 250,000 tons P 2 O 5 per annum. It is necessary to combine these facilities with uranium production plant. (author)

On the geology of the uranium mineralization in the Swiss Alps

International Nuclear Information System (INIS)

Gillieron, F.

1988-01-01

Numerous radiometric anomalies and several uranium occurrences were found in the Swiss Alps by systematic prospecting of selected areas carried out between 1957 and 1984. Most of the uranium indications lie in a rather narrow belt that follows roughly the valleys of the Rhone und of the Rhine Anterior, from Martigny onto Ilanz and extending northwards towards the Lake of Walenstadt. The uranium occurrences were found in the following geological environments: - permocarboniferous continental, variably metamorphosed series, belonging either to the formation of the 'Verrucano' or to the Penninic St. Bernhard nappe; - muscovite-chlorite-albite gneisses belonging to the pre-Westphalian basement of the St. Bernhard nappe; - muscovite-chlorite gneisses and phyllites of the Hercynian Tavetsch massiv; - muscovite-biotite gneisses within the southern border of the Aar massif; - Vallorcine granite of the Auguilles-Rouges massiv and polymetamorphic biotite gneisses along its northwestern contact zone. The possible geological (or 'in situ') resources are estimated to be 50-250 tonnes uranium in each one of the investigated mineralization zones of some importance; the respective estimated grades are 50-250 ppm U. Therefore the occurrences are actually of no economic value. (author) 25 figs., 1 tab., refs

Uranium and the use of depleted uranium in weaponry; L'uranium et les armes a l'uranium appauvri

Energy Technology Data Exchange (ETDEWEB)

Roussel, R

2000-07-01

In this brief report the author shows that the use of shells involving a load of depleted uranium might lead to lasting hazards to civil population and environment. These hazards come from the part of the shell that has been dispersed as contaminating radioactive dusts. The author describes some features of radioactivity and highlights the role of Uranium-238 as a provider of energy to the planet. (A.C.)

Technique of uranium exploration in tropical rain forests as applied in Sumatra and other tropical areas

International Nuclear Information System (INIS)

Hahn, L.

1983-01-01

The technique of uranium prospecting in areas covered by tropical rain forest is discussed using a uranium exploration campaign conducted from 1976 to 1978 in Western Sumatra as an example. A regional reconnaissance survey using stream sediment samples combined with radiometric field measurements proved ideal for covering very large areas. A mobile field laboratory was used for the geochemical survey. Helicopter support in diffult terrain was found to be very efficient and economical. A field procedure for detecting low uranium concentrations in stream water samples is described. This method has been successfully applied in Sarawak. To distinguish meaningful uranium anomalies in water from those with no meaning for prospecting, the correlations between U content and conductivity of the water and between U content and Ca and HCO 3 content must be considered. This method has been used successfully in a geochemical survey in Thailand. (author)

Gravitational Anomaly and Transport Phenomena

International Nuclear Information System (INIS)

Landsteiner, Karl; Megias, Eugenio; Pena-Benitez, Francisco

2011-01-01

Quantum anomalies give rise to new transport phenomena. In particular, a magnetic field can induce an anomalous current via the chiral magnetic effect and a vortex in the relativistic fluid can also induce a current via the chiral vortical effect. The related transport coefficients can be calculated via Kubo formulas. We evaluate the Kubo formula for the anomalous vortical conductivity at weak coupling and show that it receives contributions proportional to the gravitational anomaly coefficient. The gravitational anomaly gives rise to an anomalous vortical effect even for an uncharged fluid.

International Uranium Resources Evaluation Project (IUREP) national favourability studies: Iran

International Nuclear Information System (INIS)

1977-12-01

Iran is on the southern flank of the Alpine-Himalayan mountain system and has within its extensive boundaries rocks ranging from crystalline metamorphics and igneous rocks of Precambrian age to sediments of Tertiary - Pleistocene age, some of which could be considered as potentially favourable for uranium deposits. The search for uranium started about 1959 and in the following years some 40 radioactive anomalies and a small number of uranium occurrences were identified. In 1977 the Atomic Energy Organization of Iran greatly expanded its exploration activities and contracted for 895,000 line kilometres to be flown by three contractors in an aerial spectrometric survey designed to cover almost the two fifths of the whole country. The follow-up of this survey will continue for several years. Purely on the basis of its size (1,648,004 km 2 ), its several favourable host rock areas, its location on the flank of the Alpine-Himalayan system and the relatively small amount of systematic exploration coverage completed to date the Speculative Potential could be placed in the 50,000 - 100,000 tonnes category. (author)

Epithermal uranium deposits in a volcanogenic context: the example of Nopal 1 deposit, Sierra de Pena Blanca, Mexico

Science.gov (United States)

Calas, G.; Angiboust, S.; Fayek, M.; Camacho, A.; Allard, T.; Agrinier, P.

2009-12-01

The Peña Blanca molybdenum-uranium field (Chihuahua, Mexico) exhibits over 100 airborne anomalies hosted in tertiary ignimbritic ash-flow tuffs (44 Ma) overlying the Pozos conglomerate and a sequence of Cretaceous carbonate rocks. Uranium occurrences are associated with breccia zones at the intersection of two or more fault systems. Periodic reactivation of these structures associated with Basin and Range and Rio Grande tectonic events resulted in the mobilization of U and other elements by meteoric fluids heated by geothermal activity. Trace element geochemistry (U, Th, REE) provides evidence for local mobilization of uranium under oxidizing conditions. In addition, O- and H-isotope geochemistry of kaolinite, smectite, opal and calcite suggests that argillic alteration proceeded at shallow depth with meteoric water at 25-75 °C. Focussed along breccia zones, fluids precipitated several generations of pyrite and uraninite together with kaolinite, as in the Nopal 1 mine, indicating that mineralization and hydrothermal alteration of volcanic tuffs are contemporaneous. Low δ34S values (~ -24.5 ‰) of pyrites intimately associated with uraninite suggest that the reducing conditions at the origin of the U-mineralization arise from biological activity. Later, the uplift of Sierra Pena Blanca resulted in oxidation and remobilization of uranium, as confirmed by the spatial distribution of radiation-induced defect centers in kaolinites. These data show that tectonism and biogenic reducing conditions can play a major role in the formation and remobilization of uranium in epithermal deposits. By comparison with the other uranium deposits at Sierra Pena Blanca and nearby Sierra de Gomez, Nopal 1 deposit is one of the few deposits having retained a reduced uranium mineralization.

Evolution of uranium distribution and speciation in mill tailings, COMINAK Mine, Niger

International Nuclear Information System (INIS)

Déjeant, Adrien; Galoisy, Laurence; Roy, Régis; Calas, Georges; Boekhout, Flora; Phrommavanh, Vannapha; Descostes, Michael

2016-01-01

This study investigated the evolution of uranium distribution and speciation in mill tailings from the COMINAK mine (Niger), in production since 1978. A multi-scale approach was used, which combined high resolution remote sensing imagery, ICP-MS bulk rock analyses, powder X-ray diffraction, Scanning Electron Microscopy, Focused Ion Beam — Transmission Electron Microscopy and X-ray Absorption Near Edge Spectroscopy. Mineralogical analyses showed that some ore minerals, including residual uraninite and coffinite, undergo alteration and dissolution during tailings storage. The migration of uranium and other contaminants depends on (i) the chemical stability of secondary phases and sorbed species (dissolution and desorption processes), and (ii) the mechanical transport of fine particles bearing these elements. Uranium is stabilized after formation of secondary uranyl sulfates and phosphates, and adsorbed complexes on mineral surfaces (e.g. clay minerals). In particular, the stock of insoluble uranyl phosphates increases with time, thus contributing to the long-term stabilization of uranium. At the surface, a sulfate-cemented duricrust is formed after evaporation of pore water. This duricrust limits water infiltration and dust aerial dispersion, though it is enriched in uranium and many other elements, because of pore water rising from underlying levels by capillary action. Satellite images provided a detailed description of the tailings pile over time and allow monitoring of the chronology of successive tailings deposits. Satellite images suggest that uranium anomalies that occur at deep levels in the pile are most likely former surface duricrusts that have been buried under more recent tailings. - Highlights: • The evolution of U distribution and speciation in mill tailings is investigated. • High resolution satellite images provide useful information on tailings evolution. • U and many other elements are enriched in a sulfate-rich duricrust. • Formation of

Evolution of uranium distribution and speciation in mill tailings, COMINAK Mine, Niger

Energy Technology Data Exchange (ETDEWEB)

Déjeant, Adrien, E-mail: adrien.dejeant@normalesup.org [Institut de Minéralogie, de Physique des Matériaux et de Cosmochimie, Case 115, 4 place Jussieu, 75005 Paris (France); Université Paris Diderot — Paris VII, 5 rue Thomas Mann, 75013 Paris (France); Galoisy, Laurence [Institut de Minéralogie, de Physique des Matériaux et de Cosmochimie, Case 115, 4 place Jussieu, 75005 Paris (France); Université Pierre et Marie Curie — Paris VI, 4 place Jussieu, 75005 Paris (France); Roy, Régis [AREVA Mines — Geoscience Department, Tour AREVA, 1 place Jean Millier, 92084 Paris, La Défense (France); Calas, Georges; Boekhout, Flora [Institut de Minéralogie, de Physique des Matériaux et de Cosmochimie, Case 115, 4 place Jussieu, 75005 Paris (France); Université Pierre et Marie Curie — Paris VI, 4 place Jussieu, 75005 Paris (France); Phrommavanh, Vannapha; Descostes, Michael [AREVA Mines — R& D Department, BAL 0414C-2, Tour AREVA, 1 place Jean Millier, 92084 Paris, La Défense (France)

2016-03-01

This study investigated the evolution of uranium distribution and speciation in mill tailings from the COMINAK mine (Niger), in production since 1978. A multi-scale approach was used, which combined high resolution remote sensing imagery, ICP-MS bulk rock analyses, powder X-ray diffraction, Scanning Electron Microscopy, Focused Ion Beam — Transmission Electron Microscopy and X-ray Absorption Near Edge Spectroscopy. Mineralogical analyses showed that some ore minerals, including residual uraninite and coffinite, undergo alteration and dissolution during tailings storage. The migration of uranium and other contaminants depends on (i) the chemical stability of secondary phases and sorbed species (dissolution and desorption processes), and (ii) the mechanical transport of fine particles bearing these elements. Uranium is stabilized after formation of secondary uranyl sulfates and phosphates, and adsorbed complexes on mineral surfaces (e.g. clay minerals). In particular, the stock of insoluble uranyl phosphates increases with time, thus contributing to the long-term stabilization of uranium. At the surface, a sulfate-cemented duricrust is formed after evaporation of pore water. This duricrust limits water infiltration and dust aerial dispersion, though it is enriched in uranium and many other elements, because of pore water rising from underlying levels by capillary action. Satellite images provided a detailed description of the tailings pile over time and allow monitoring of the chronology of successive tailings deposits. Satellite images suggest that uranium anomalies that occur at deep levels in the pile are most likely former surface duricrusts that have been buried under more recent tailings. - Highlights: • The evolution of U distribution and speciation in mill tailings is investigated. • High resolution satellite images provide useful information on tailings evolution. • U and many other elements are enriched in a sulfate-rich duricrust. • Formation of

Stream-sediment geochemical exploration for uranium in Narigan area Central Iran

International Nuclear Information System (INIS)

Yazdi, M.; Khoshnoodi, K.; Kavand, M.; Ashteyani, A. R.

2009-01-01

Uranium deposits of Iran occur mainly in the Central Iran zone. Several uranium deposits have been discovered in this zone. The Narigan area is one of the most important uranium mineralized area in this zone. The uranium bearing sequences in this area are contained in the plutonic to volcanic rocks of Narigan which intruded to the Pre-Cambrian pyroclastics rocks. Plutonic and volcanic rocks are granite, rhyolite and volcanoclastic. Diabasic dykes have been intruded to these igneous rocks. The plutonic and volcanic rocks have been covered by Cretaceous limestones which seem to be youngest the rocks in this area. The aim of our project is to develop a regional exploration strategy for uranium in these igneous rocks. A grid-based sampling was planned following the results of the previous geochemical mapping at a scale of 1:100,000, integrated with geophysical data and alteration zones and outcrop of intrusive rocks. The following results are based on geological, and stream geochemical explorations in 1:20000 scale of this area. During this study 121 samples were collected from the stream sediments of <80 mesh for final sampling. Ten percent of the samples were used for checking laboratories errors. The samples were collected according to conventional methods from 30-40 cm depth of stream sediments. Finally, geochemical and radiometric data were combined and the results introduced 3 anomalies in the Narigan area

International Uranium Resources Evaluation Project (IUREP) orientation phase mission report: Colombia. February - March 1980

International Nuclear Information System (INIS)

Cameron, J.; Meunier, A.R.; Tauchid, M.

1980-01-01

The basic objective of IUREP is to 'review the present body of knowledge pertinent to the existence of uranium resources, to review and evaluate the potential for discovery of additional uranium resources, and to suggest new exploration efforts which might be carried out in promising new areas in collaboration with the countries concerned'. Following the initial bibliographic study, which formed Phase I of IUREP, it was envisaged that a further assessment in co-operation with the country in question would lead to a better delineation of areas of high potential and a more reliable estimate as to the degree of favourability for the discovery of additional uranium resources. It was planned that such work would be accomplished through field missions to the country and that these field missions and the resulting report would constitute the IUREP Orientation Phase. The purpose of the Orientation Mission to Colombia was (i) to develop a better understanding of the uranium potential of the country, (ii) to delineate areas favourable for the discovery of speculative uranium resources, (iii) to make recommendations, as appropriate, on the best methods for evaluating the favourable areas, operating procedures and estimated possible costs, (iv) to develop the logistical data required to carry out any possible further work, and (v) to compile a report that would be immediately available to the Colombian authorities. Uranium exploration in Colombia is of very recent date, with the majority of activities getting under way only after 1970. In spite of the limited work that has been done, however, over 1300 radioactive anomalies have been recorded. The total number of uranium mineral occurrences resulting from follow-up work is still very small, and some are unusual in world terms. Topographic and geographic conditions in Colombia make geological and exploration work very difficult and costly, especially in the Cordilleras and the Interior Zone (Llanos Orientales). There are, at

Uranium

International Nuclear Information System (INIS)

Hamdoun, N.A.

2007-01-01

The article includes a historical preface about uranium, discovery of portability of sequential fission of uranium, uranium existence, basic raw materials, secondary raw materials, uranium's physical and chemical properties, uranium extraction, nuclear fuel cycle, logistics and estimation of the amount of uranium reserves, producing countries of concentrated uranium oxides and percentage of the world's total production, civilian and military uses of uranium. The use of depleted uranium in the Gulf War, the Balkans and Iraq has caused political and environmental effects which are complex, raising problems and questions about the effects that nuclear compounds left on human health and environment.

Global anomalies in chiral gauge theories on the lattice

International Nuclear Information System (INIS)

Baer, O.; Campos, I.

2000-01-01

We discuss the issue of global anomalies in chiral gauge theories on the lattice. In Luescher's approach, these obstructions make it impossible to define consistently a fermionic measure for the path integral. We show that an SU(2) theory has such a global anomaly if the Weyl fermion is in the fundamental representation. The anomaly in higher representations is also discussed. We finally show that this obstruction is the lattice analogue of the SU(2) anomaly first discovered by Witten. (orig.)

Drawing of uranium in {gamma} phase; Filage de l'uranium en phase gamma

Energy Technology Data Exchange (ETDEWEB)

Stohr, J A [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires; Chevigny, R [Conpagnie, Pechiney, 73 - Chambery (France)

1955-07-01

It describes the study of working and drawing of uranium in {gamma} phase. In a first part, the forgeable characteristics of uranium metal in the three different phases ({alpha}, {beta} and {gamma}) are compared by using BASTIEN-PORTEVIN method. The different experiments are testing the behaviour metal in each phase under different stresses and a temperature gradient as slow and shock traction, slow and shock compression, resilience, flexibility. Results show that optimum conditions for uranium drawing is uranium in phase {gamma}. In a second part, it described the drawing method and process. The uranium rods obtained by this technique are of very good quality. In addition, the material wear is very low which permits a low production cost. Finally, the uranium rod physical properties are studied. (M.P.)

Uranium extraction from gold-uranium ores

Energy Technology Data Exchange (ETDEWEB)

Laskorin, B.N.; Golynko, Z.Sh.

1981-01-01

The process of uranium extraction from gold-uranium ores in the South Africa is considered. Flowsheets of reprocessing gold-uranium conglomerates, pile processing and uranium extraction from the ores are presented. Continuous counter flow ion-exchange process of uranium extraction using strong-active or weak-active resins is noted to be the most perspective and economical one. The ion-exchange uranium separation with the succeeding extraction is also the perspective one.

International Uranium Resources Evaluation Project (IUREP) national favourability studies: Turkey

International Nuclear Information System (INIS)

1977-08-01

Turkey has an area of 296 185 sq mi or 767 120 square kilometers. The geology is dominated lay Tertiary and post-Tertiary rocks which are very widespread but extensive outcrops of Mesozoic rocks also occur. Paleozoic rocks, mainly gneisses, mica schists and quartzites occur in the ancient massifs, principally the Istranca massif in Thrace, the Merideres massif in western Anatolia and the Karrshir massif in central Anatolia. Prospecting for uranium began in Turkey in 1953 and the Atomic Energy Raw Materials Division of the Maden Tetkikive Arama Enstitusu (M.T.A.) was founded in 1956. By 1962 a total of 78% of the whole country had been covered by serial radiometric reconnaissance prospecting. Uranium was discovered at Kasar in western Anatolia in 1961 and several hundred tons of reserves estimated two years later. Uranium prospecting was largely recessed from 1963 to 1967. IAEA/UNDP assistance was provided in 1962-63 and 1965 and between 1974 and 1977 in a detailed exploration programme in the Kasar area. In the whole country nearly 600 anomalies and occurrences had been identified by 1963. Several occurrences principally in Western Anatolia had been assigned a small reserve. A recent official estimate places the total national reserve at 3150 tonnes uranium in the less than 30% category of reasonably assured resources. A speculative Potential of between 30,000 and 50,000 tonnes uranium is considered to be reasonable. (author)

Purification of uranium metal

International Nuclear Information System (INIS)

Suzuki, Kenji; Shikama, Tatsuo; Ochiai, Akira.

1993-01-01

We developed the system for purifying uranium metal and its metallic compounds and for growing highly pure uranium compounds to study their intrinsic physical properties. Uranium metal was zone refined under low contamination conditions as far as possible. The degree of the purity of uranium metal was examined by the conventional electrical resistivity measurement and by the chemical analysis using the inductive coupled plasma emission spectrometry (ICP). The results show that some metallic impurities evaporated by the r.f. heating and other usual metallic impurities moved to the end of a rod with a molten zone. Therefore, we conclude that the zone refining technique is much effective to the removal of metallic impurities and we obtained high purified uranium metal of 99.99% up with regarding to metallic impurities. The maximum residual resistivity ratio, the r.r.r., so far obtained was about 17-20. Using the purified uranium, we are attempting to grow a highly pure uranium-titanium single crystals. (author)

Method for converting uranium oxides to uranium metal

International Nuclear Information System (INIS)

Duerksen, W.K.

1988-01-01

A method for converting uranium oxide to uranium metal is described comprising the steps of heating uranium oxide in the presence of a reducing agent to a temperature sufficient to reduce the uranium oxide to uranium metal and form a heterogeneous mixture of a uranium metal product and oxide by-products, heating the mixture in a hydrogen atmosphere at a temperature sufficient to convert uranium metal in the mixture to uranium hydride, cooling the resulting uranium hydride-containing mixture to a temperature sufficient to produce a ferromagnetic transition in the uranium hydride, magnetically separating the cooled uranium hydride from the mixture, and thereafter heating the separated uranium hydride in an inert atmosphere to a temperature sufficient to convert the uranium hydride to uranium metal

Thermodynamic mechanism of density anomaly of liquid water

Directory of Open Access Journals (Sweden)

Makoto eYasutomi

2015-03-01

Full Text Available Although density anomaly of liquid water has long been studied by many different authors up to now, it is not still cleared what thermodynamic mechanism induces the anomaly. The thermodynamic properties of substances are determined by interparticle interactions. We analyze what characteristics of pair potential cause the density anomaly on the basis of statistical mechanics and thermodynamics using a thermodynamically self-consistent Ornstein-Zernike approximation (SCOZA. We consider a fluid of spherical particles with a pair potential given by a hard-core repulsion plus a soft-repulsion and an attraction. We show that the density anomaly occurs when the value of the soft-repulsive potential at hard-core contact is in some proper range, and the range depends on the attraction. Further, we show that the behavior of the excess internal energy plays an essential role in the density anomaly and the behavior is mainly determined by the values of the soft-repulsive potential, especially near the hard core contact. Our results show that most of ideas put forward up to now are not the direct causes of the density anomaly of liquid water.

National Uranium Resource Evaluation. Groundwater prospecting for sandstone-type uranium deposits: the merits of mineral-solution equilibria versus single element tracer methods. Final report

International Nuclear Information System (INIS)

Chatham, J.R.; Wanty, R.B.; Langmuir, D.

1981-02-01

Groundwaters from aquifers in two different sandstone-type uranium mining districts in Texas and Wyoming were collected and chemically analyzed. The data were used to compare the merits of using the computed saturation state of the groundwater with respect to uranium minerals, to that of single-element tracers in the groundwater for geochemical prospecting. Chemical properties of the Texas waters were influenced locally by preferred groundwater flow within buried fluvial channel deposits; upward leakage of brines along growth faults into the aquifer; and the establishment of a redox interface (Eh = 0 volts) within the aquifer. Chemical characteristics of aquifer waters in Wyoming changed gradually downdip, reflecting regional homogeneity in groundwater flow and a more gradual downdip reduction of Eh values than in Texas. The most reliable indicator of reduced uranium ore in both study sites was the saturation state of groundwater with respect to uraninite or coffinite. For both minerals, this saturation state increased from 15 to 20 log units as reduced ore deposits were approached over distances of 3 to 4.5 km in both sites. Tyuyamunite and carnotite approached or exceeded saturation in some oxidized waters of the Texas site reflecting possible occurrences of these minerals. The radiogenic elements Ta and Rn were excellent indicators of ore directly within the deposits, where anomalous values were 2 to 3 orders of magnitude above background. Helium also increased near the ore, although anomalies were generally displaced in the direction of groundwater flow. Uranium and uranium isotope values did not individually pinpoint ore, but may be used together to classify groundwater samples in terms of their position relative to uranium mineralization

Preliminary evaluation of the uranium favorability in the Kaiparowits Plateau Region, Garfield and Kane Counties, Utah

International Nuclear Information System (INIS)

Dubyk, W.S.; Young, P.

1978-05-01

The basal sandstone of the Chinle Formation (Upper Triassic) and the Salt Wash Member of the Morrison Formation (Upper Jurassic) in the Kaiparowits Plateau, southcentral Utah, were evaluated in terms of uranium potential. Both surface and subsurface data were utilized. Favorability of the basal Chinle sandstone was based on (1) presence of intermediate-size sandstone-filled channels cut into the Moenkopi; (2) presence of carbonaceous material; (3) an adequate source of uranium; and (4) gamma-ray anomalies from test-hole logs. Favorability of the Salt Wash Member of the Morrison Formation was based on (1) sandstone-mudstone ratios that approach equality, and (2) presence of thick sandstone lenses, carbonaceous material, and halos of light-tan to brown limonite staining. Although the basal Chinle sandstone and the Salt Wash Member of the Morrison contain sizable uranium deposits throughout much of the Colorado Plateau, both units lack characteristics that are favorable for significant uranium deposits in the Kaiparowits Plateau

Uranium exploration status in Bangladesh: Conceptual feasibility studies

International Nuclear Information System (INIS)

Majumder, R.; Khalil, M.; Rashid, M.

2014-01-01

. As Bangladesh is drained by the Padma-Meghna-Jamuna systems, there are numerous sand bars in those river channels. These sand bars are the prospective locations for uranium bearing minerals. In Bangladesh a regional reconnaissance survey was carried out in more than 2000 sq. km areas of greater Chittagong and Chittagong Hill Tracts and Sylhet districts that has resulted in the identification of more than 150 surface radiometric anomalies. Most of the samples collected from anomalous beds contain uranium ranging from 10 - 300 ppm. The highest radiometric counts occurred in Phooltala Reserve Forest within the Harargaj anticline of Moulavi bazar district, which was about 6000 cps (60 times the background counts). Chemical analysis of this sample has indicated the presence of 1020 ppm total uranium and two uranium bearing minerals namely uranothorite and thorianite have been discovered in the rock samples. Besides, anomalous reading of 25 times higher than the background was observed in the crystalline basement rocks at Mitapukur in Rangpur district. Moreover, in recent studies conducted by the Geological Survey of Bangladesh (GSB), higher radiometric counts have been observed in sand bar deposits of the Brahmaputra River. (author)

Anomaly mediation deformed by axion

Energy Technology Data Exchange (ETDEWEB)

Nakayama, Kazunori, E-mail: kazunori@hep-th.phys.s.u-tokyo.ac.jp [Department of Physics, University of Tokyo, Bunkyo-ku, Tokyo 113-0033 (Japan); Kavli Institute for the Physics and Mathematics of the Universe, University of Tokyo, Kashiwa 277-8583 (Japan); Yanagida, Tsutomu T. [Kavli Institute for the Physics and Mathematics of the Universe, University of Tokyo, Kashiwa 277-8583 (Japan)

2013-05-13

We show that in supersymmetric axion models the axion supermultiplet obtains a sizable F-term due to a non-supersymmetric dynamics and it generally gives the gaugino masses comparable to the anomaly mediation contribution. Thus the gaugino mass relation predicted by the anomaly mediation effect can be significantly modified in the presence of axion to solve the strong CP problem.

Advances in the exploration model for Athabasca unconformity uranium deposits

International Nuclear Information System (INIS)

Wheatley, K.; Murphy, J.; Leppin, M.; Cutts, C.; Climie, J.A.

1997-01-01

This paper covers the genetic model of ore formation and exploration techniques Uranerz Exploration and Mining is presently using to explore for unconformity uranium deposits in the deeper parts of the Athabasca Basin. The main objectives of this paper are: 1) to present a genetic model for unconformity uranium deposits which is being used in our current exploration strategy, and 2) to present the sequence of exploration techniques used by Uranerz to explore for uranium in areas of the Athabasca Basin with up to 1000 m of sandstone cover. The Athabasca unconformity deposits are located in northern Saskatchewan, Canada. Within the Precambrian Athabasca Basin, exploration companies have discovered 18 uranium deposits. These contain more than 500 million kilograms of uranium, with average grades ranging from 0.3 to 12%. Uranerz discovered the Key Lake deposits in 1975, currently the largest and richest open pit uranium mine in the world. Uranerz also holds interests in the Rabbit Lake, Midwest Lake and McArthur River deposits, all in Saskatchewan, and is also actively exploring for uranium worldwide. The first discovery in the eastern Athabasca Basin was in 1968 at Rabbit Lake, followed by Key Lake in 1975. Both deposits had surficial indicators, such as radioactive boulders, strong geochemical anomalies in the surrounding lakes and swamps, and well-defined geophysical signatures. After the Key Lake discovery, an exploration model was devised which incorporated the underlying graphitic horizon and its strong electro-magnetic signature. Since then, there have been numerous new discoveries made by systematically drilling along these electro-magnetic conductors. The advancements in geophysical and geochemical techniques have led to discoveries at increasing depths. In 1988, the McArthur River deposit was discovered at a depth of 500 m. (author). 6 refs

Low Risk Anomalies?

DEFF Research Database (Denmark)

Schneider, Paul; Wagner, Christian; Zechner, Josef

. Empirically, we find that option-implied ex-ante skewness is strongly related to ex-post residual coskewness and alphas. Beta- and volatility-based low risk anomalies are largely driven by a single principal component, which is in turn largely explained by skewness. Controlling for skewness renders the alphas......This paper shows that stocks' CAPM alphas are negatively related to CAPM betas if investors demand compensation for negative skewness. Thus, high (low) beta stocks appear to underperform (outperform). This apparent anomaly merely reflects compensation for residual coskewness ignored by the CAPM...... of betting-against-beta and -volatility insignificant....

Global anomalies in chiral lattice gauge theories

International Nuclear Information System (INIS)

Baer, O.

2000-07-01

We study global anomalies in a new approach to chiral gauge theories on the lattice, which is based on the Ginsparg-Wilson relation. In this approach, global anomalies make it impossible to define consistently a fermionic measure for the functional integral. We show that a global anomaly occurs in an SU(2) theory if the fundamental representation is used for the fermion fields. The generalization to higher representations is also discussed. In addition we establish a close relation between global anomalies and the spectral flow of the Dirac operator and employ it in a numerical computation to prove the existence of the global SU(2) anomaly in a different way. This method is inspired by an earlier work of Witten who first discovered this type of anomalies in continuum field theory. (orig.)

Gravitational anomalies

Energy Technology Data Exchange (ETDEWEB)

Leutwyler, H; Mallik, S

1986-12-01

The effective action for fermions moving in external gravitational and gauge fields is analyzed in terms of the corresponding external field propagator. The central object in our approach is the covariant energy-momentum tensor which is extracted from the regular part of the propagator at short distances. It is shown that the Lorentz anomaly, the conformal anomaly and the gauge anomaly can be expressed in terms of the local polynomials which determine the singular part of the propagator. (There are no coordinate anomalies). Except for the conformal anomaly, for which we give explicit representations only in dless than or equal to4, we consider an arbitrary number of dimensions.

Regional magnetic and gravity surveys: an aid for uranium exploration - case study from Renigunta and surrounding areas, Chitoor district, Andhra Pradesh, India

International Nuclear Information System (INIS)

Narasimha Rao, B.; Rama Krishna, P.; Markandeyulu, A.; Dwivedy, K.K.

1998-01-01

Regional magnetic and gravity data of Papanaidupet area, Chitoor district, are discussed in the light of bore hole information for selection of target areas for uranium exploration. The low-pass filtered magnetic data shows a 'smooth' picture suppressing the high frequency components in the original data. The amplitude maxima of analytic signal outline the magnetic source at depth. The Bouguer gravity residual anomaly corresponding to a double sill-like model beneath is used to explain the borehole intercepts, after petro-physical studies of the borehole samples. (author)

National Uranium Resource Evaluation: Crystal City Quadrangle, Texas

International Nuclear Information System (INIS)

Greimel, T.C.

1982-08-01

The uranium resources of the Crystal City Quadrangle, Texas, were evaluated to a depth of 1500 m using surface and subsurface geologic information. Uranium occurrences reported in the literature, in reports of the US Atomic Energy Commission and the US Geological Survey Computerized Resources Information Bank, were located, described, and sampled. Geochemical anomalies interpreted from hydrogeochemical and stream-sediment reconnaissance were also investigated and sampled in detail. Areas of uranium favorability in the subsurface were located through interpretation of lithofacies patterns and structure derived from electric-log data. Gamma-ray well logs and results of geochemical sample analyses were used as supportive data in locating these areas. Fifteen surface and subsurface favorable areas were delineated in the quadrangle. Eight are in fluvial and genetically associated facies of the Pliocene Goliad Sandstone, Miocene Oakville Sandstone, Miocene Catahoula Tuff, and Oligocene Frio Clay. One area encompasses strand plain-barrier bar, fluvial-deltaic, and lagoonal-margin facies of the Eocene Jackson Group. Two areas are in strand plain-barrier bar and probable fluvial facies of the Eocene Yegua Formation. Four areas are in fluvial-deltaic, barrier-bar, and lagoonal-margin facies of the Eocene Queen City Formation and stratigraphically equivalent units. Seventeen geologic units are considered unfavorable, and seven are unevaluated due to lack of data

Water-borne radon and hydrogeochemical based uranium exploration in Rajamundry sandstone, W. Godavari district, Andhra Pradesh

International Nuclear Information System (INIS)

Jeyagopal, A.V.; Rajaraman, H.S.; Som, Anjan

2010-01-01

The lithology and sedimentary structures of the Rajamundry Formation of the Mio-Pliocene age covering an area of 1100 sq.km. indicate that it may be a typical valley fill sediment. It is about 600 m thick comprising sandstone and clay with lignite as the main lithounits. It is continental in onshore and marine in the offshore and is in contact with Gondwana sediments and Rajamundry traps. Tertiary sandstones are important hosts for uranium mineralisation. The reducing gas (Methane or other volatile hydrocarbon) moving to uraniferous oxidising water has precipitated uranium in the sediments in South Texas and Northwest Colorado, USA: (a) along faults, (b) above petroliferous aquifers, (c) vertically above hydrocarbon accumulations and (d) oil-water interface at hydrocarbon accumulations i.e., at the points of introduction of reducent into oxidising ground waters. In this context, Rajamundry sandstone lying above the natural gas and petroleum bearing Krishna Godavari basin with faults is an important geological setting for uranium mineralisation. The exploration strategies of hydrogeochemical survey and water-borne Radon (Rn) surveys were selected in this soil-covered area. Hydrogeochemical survey carried out in the Rajamundry sandstone has brought out four hydro-uranium anomalous zones with water samples (10-45ppb) falling around Kadiyadda, Madhavaram, Erramalla and Chinna Malapalle areas of West Godavari district, Andhra Pradesh. The zones vary from 9 to 24 sq km area. Water-borne Radon was utilized as a tool for exploration of uranium in this soil covered terrain. Rn contours cluster around two zones around Kadiyadda and SW of Gollagudem wherein the Rn value is >60 counts/50 sec/500 ml. These Rn anomalies fall within the above mentioned hydrouranium anomalous zones. Gamma-ray logging of private bore wells has recorded relatively higher radioactivity in Kommugudem, which also falls in the high hydrouranium - high waterborne radon zone. These data and

Uranium XAFS analysis of kidney from rats exposed to uranium.

Science.gov (United States)

Kitahara, Keisuke; Numako, Chiya; Terada, Yasuko; Nitta, Kiyohumi; Shimada, Yoshiya; Homma-Takeda, Shino

2017-03-01

The kidney is the critical target of uranium exposure because uranium accumulates in the proximal tubules and causes tubular damage, but the chemical nature of uranium in kidney, such as its chemical status in the toxic target site, is poorly understood. Micro-X-ray absorption fine-structure (µXAFS) analysis was used to examine renal thin sections of rats exposed to uranyl acetate. The U L III -edge X-ray absorption near-edge structure spectra of bulk renal specimens obtained at various toxicological phases were similar to that of uranyl acetate: their edge position did not shift compared with that of uranyl acetate (17.175 keV) although the peak widths for some kidney specimens were slightly narrowed. µXAFS measurements of spots of concentrated uranium in the micro-regions of the proximal tubules showed that the edge jump slightly shifted to lower energy. The results suggest that most uranium accumulated in kidney was uranium (VI) but a portion might have been biotransformed in rats exposed to uranyl acetate.

Exploration on relationship between uranium and organic materials in carbonate-siliceous pelite type uranium ore deposits

International Nuclear Information System (INIS)

Dong Yongjie

1996-01-01

The author determines the content of uranium and organic carbon of part specimen of surrounding rocks and ores, which sampled from carbonate and black shale type uranium deposits in Xiushui, Jiangxi Province, and Tongcheng, Hubei Province. According to the analytical operation regulations of organic materials, extraction and separation of chloroform pitch is carried out. Internal relationships between uranium and organic derivative is discussed. The conclusion shows that: (1) certain co-relationship between U and organic carbon and chloroform extract is detected; (2) evolutionary processes of organic materials in the exogenetic uranium deposits are not all the same; (3) non-hydrocarbon is closely related to uranium, so it can be regarded as indicator of uranium gathering in exogenetic uranium deposits

Uranium in soil, forest litter and living plant material above three uranium mineralizations in Northern Sweden

International Nuclear Information System (INIS)

Ek, John

1982-01-01

In order to investigate the feasibility of biogeochemical sampling media in uranium exploration, samples from the most common trees and low bushes together with forest litter were collected over the areas of three uranium mineralizations in Northern Sweden and analyzed for uranium. The results were compared with uranium content of the till and its radioactivity. The average uranium content was low for all sample types and considerably lower in the ash of the organic sample types compared to that of the till. No sample type showed any tendency of having higher uranium concentration above mineralizations compared to background areas. These results suggest that, under conditions prevailing in Sweden, the investigated sample types are not suitable for uranium exploration

Uranium-enriched granites in Sweden

International Nuclear Information System (INIS)

Wilson, M.R.; Aakerblom, G.

1980-01-01

Granites with uranium contents higher than normal occur in a variety of geological settings in the Swedish Precambrian, and represent a variety of granite types and ages. They may have been generated by the anatexis of continental crust or processes occurring at a much greater depth. They commonly show enrichment in F, Sn, W and/or Mo. Only in one case is an important uranium mineralization thought to be directly related to a uranium-enriched granite, while the majority of epigenetic uranium mineralizations with economic potential are related to hydrothermal processes in areas where the bedrock is regionally uranium-enhanced. (author)

Uranium enriched granites in Sweden

International Nuclear Information System (INIS)

Wilson, M.R.; Aakerblom, G.

1980-01-01

Granites with uranium contents higher than normal occur in a variety of geological settings in the Swedish Precambrian, and represent a variety of granite types and ages. They may have been generated by (1) the anatexis of continental crust (2) processes occurring at a much greater depth. They commonly show enrichement in F, Sn, W and/or Mo. Only in one case is an important uranium mineralization thought to be directly related to a uranium-enriched granite, while the majority of epigenetic uranium mineralizations with economic potential are related to hydrothermal processes in areas where the bedrock is regionally uranium-enhanced. (Authors)

Method for converting uranium oxides to uranium metal

Science.gov (United States)

Duerksen, Walter K.

1988-01-01

A process is described for converting scrap and waste uranium oxide to uranium metal. The uranium oxide is sequentially reduced with a suitable reducing agent to a mixture of uranium metal and oxide products. The uranium metal is then converted to uranium hydride and the uranium hydride-containing mixture is then cooled to a temperature less than -100.degree. C. in an inert liquid which renders the uranium hydride ferromagnetic. The uranium hydride is then magnetically separated from the cooled mixture. The separated uranium hydride is readily converted to uranium metal by heating in an inert atmosphere. This process is environmentally acceptable and eliminates the use of hydrogen fluoride as well as the explosive conditions encountered in the previously employed bomb-reduction processes utilized for converting uranium oxides to uranium metal.

Dazai super-large uranium-bearing germanium deposit in western Yunnan region metallogenic geological conditions and prospect

International Nuclear Information System (INIS)

Han Yanrong; Yuan Qingbang; Li Yonghua; Zhang Ling; Dai Jiemin

1995-05-01

The Dazai super-large uranium-bearing germanium deposit is located in Bangmai Fault Basin, Western Yunnan, China. The basin basement is migmatitic granite and the cover is miocene coal-bearing clastics, Bangmai Formation. The basin development had undergone faulted rhombus basin forming, synsedimentary structure-developing and up-lifted-denuded stages. Synsedimentary faults had controlled distribution of sedimentary formation and lithofacies, and uranium and germanium mineralization. Germanium ore-bodies occur mainly in master lignite-bed of lower rhythmite. Hosted germanium-lignite is taken as main ore-type. Germanium occurs in vitrinite of lignite in the form of metal-organic complex. The metallogenetic geological conditions of the deposit are that ground preparation is uplift zone-migmatitic granite-fault basin-geothermal anomaly area, rich and thick ore-body is controlled by synsedimentary fault, peat-bog phase is favorable to accumulation for ore-forming elements, and unconformity between overlying cover and underlying basement is a channel-way of mineralizing fluid. A multiperiodic composite, being regarded sedimentation and diagenesis as a major process, uranium and germanium ore deposit has been formed through two mineralization. Four prospecting areas have been forecasted and two deposits have been accordingly discovered again. Technical-economic provableness shows that the deposit is characterized by shallow-buried, rich grade, large scale, easy mining and smelting. (9 figs.)

Uranium and the use of depleted uranium in weaponry

International Nuclear Information System (INIS)

Roussel, R.

2000-01-01

In this brief report the author shows that the use of shells involving a load of depleted uranium might lead to lasting hazards to civil population and environment. These hazards come from the part of the shell that has been dispersed as contaminating radioactive dusts. The author describes some features of radioactivity and highlights the role of Uranium-238 as a provider of energy to the planet. (A.C.)

National Uranium Resource Evaluation. Aerial gamma ray and magnetic survey, Tawas City and Flint quadrangles, Michigan. Final report

International Nuclear Information System (INIS)

1981-07-01

The Tawas City and Flint quadrangles of Michigan cover a land area of 6500 square miles, and an additional water surface area of 7200 square miles. Extremely thick Paleozoic deposits overlie a regional downwarp of the Precambrian basement called the Michigan Basin. These Paleozoic deposits shoal to only 1500 feet in the northeast corner. The entire survey area is covered by a mantle of Quaternary glacial material. A search of available literature revealed no economically feasible uranium deposits. Thirty-five uranium anomalies were detected and are discussed briefly. All appear to have cultural, and/or locally unsaturated associations, and none appear to contain significant measured quantities of uranium. Magnetic data appear to be in good agreement with existing structural interpretations of the area

Sandstone-type uranium deposits

International Nuclear Information System (INIS)

Austin, S.R.; D'Andrea, R.F. Jr.

1978-01-01

Three overall factors are necessary for formation of uranium deposits in sandstone: a source of uranium, host rocks capable of transmitting uranium-bearing solutions, and a precipitant. Possible sources of uranium in sandstone-type deposits include groundwaters emanating from granitic highlands, arkosic sediments, tuffaceous material within or overlying the host rocks, connate fluids, and overlying black shales. The first three sources are considered the most likely. Host rocks are generally immature sandstones deposited in alluvial-fan, intermontane-basin or marginal-marine environments, but uranium deposits do occur in well-winnowed barrier-bar or eolian sands. Host rocks for uranium deposits generally show coefficients of permeability on the order of 1 to 100 gal/day/ft 2 . Precipitants are normally agents capable of reducing uranium from the uranyl to the uranous state. The association of uranium with organic matter is unequivocal; H 2 S, a powerful reductant, may have been present at the time of formation of some deposits but may go unnoticed today. Vanadium can serve to preserve the tabular characteristics of some deposits in the near-surface environment, but is considered an unlikely primary precipitant for uranium. Uranium deposits in sandstone are divided into two overall types: peneconcordant deposits, which occur in locally reducing environments in otherwise oxidized sandstones; and roll-type deposits, which occur at the margin of an area where an oxidized groundwater has permeated an otherwise reduced sandstone. Uranium deposits are further broken down into four subclasses; these are described

Holonomy anomalies

International Nuclear Information System (INIS)

Bagger, J.; Nemeschansky, D.; Yankielowicz, S.

1985-05-01

A new type of anomaly is discussed that afflicts certain non-linear sigma models with fermions. This anomaly is similar to the ordinary gauge and gravitational anomalies since it reflects a topological obstruction to the reparametrization invariance of the quantum effective action. Nonlinear sigma models are constructed based on homogeneous spaces G/H. Anomalies arising when the fermions are chiral are shown to be cancelled sometimes by Chern-Simons terms. Nonlinear sigma models are considered based on general Riemannian manifolds. 9 refs

Uranium

International Nuclear Information System (INIS)

Cuney, M.; Pagel, M.; Leroy, J.

1992-01-01

First, this book presents the physico-chemical properties of Uranium and the consequences which can be deduced from the study of numerous geological process. The authors describe natural distribution of Uranium at different scales and on different supports, and main Uranium minerals. A great place in the book is assigned to description and classification of uranium deposits. The book gives also notions on prospection and exploitation of uranium deposits. Historical aspects of Uranium economical development (Uranium resources, production, supply and demand, operating costs) are given in the last chapter. 7 refs., 17 figs

Uranium, thorium and rare earth elements distribution from different iron quadrangle spring waters

Energy Technology Data Exchange (ETDEWEB)

Ferreira, Cláudia A.; Palmieri, Helena E.L.; Menezes, Maria A. de B.C.; Rodrigues, Paulo C.H., E-mail: cferreiraquimica@yahoo.com.br, E-mail: help@cdtn.br, E-mail: menezes@cdtn.br, E-mail: pchr@cdtn.br [Centro de Desenvolvimento da Tecnologia Nuclear (CDTN/CNEN-MG), Belo Horizonte, MG (Brazil)

2017-11-01

This study was conducted to evaluate the concentrations of thorium, uranium and the rare earth elements (REE) in 26 spring waters, as well as the patterns of the REE of the samples from the Cercadinho, Moeda and Caue aquifers in different municipalities of the Iron Quadrangle (Quadrilatero Ferrifero), located in the central-southeast of Minas Gerais state. The pH value of the ground waters ranged from 3.8 to 7.0, indicating an acid nature of most of the spring waters. The investigation of REE speciation showed that all the REEs exist in the free X{sup 3+} ionic forms, under the prevailing Eh and pH conditions. In the studied samples the uranium concentrations (<2.3-1176 ng L{sup -1}) were below the guideline level set by Brazilian legislation (Ministry of Health 518- 03/2004). Thorium concentrations ranged from <0.39-11.0 ng L{sup -1} and the sum of the REE ranged from 6.0 to 37657 ng L{sup -1}. As there are no permissible limits related for the REE and thorium for different water quality standards in Brazil, more attention must be paid to the local residents' health risk caused by spring waters (REEs were > 1000 ng L{sup -1}) originating from aquifers located in Sabara, Barao de Cocais, Santa Barbara, Mario Campos, Congonhas and Lavras Novas. The REEs patterns in the spring waters from the Cercadinho, Caue and Moeda aquifers are characterized by middle REE (MREE) enrichment compared to light REE (LREE) and heavy REEs (HREE), negative Ce anomalies (except for one sample) and positive Eu anomalies in all three aquifers studied. (author)

Drawing of uranium in {gamma} phase; Filage de l'uranium en phase gamma

Energy Technology Data Exchange (ETDEWEB)

Stohr, J.A. [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires; Chevigny, R. [Conpagnie, Pechiney, 73 - Chambery (France)

1955-07-01

It describes the study of working and drawing of uranium in {gamma} phase. In a first part, the forgeable characteristics of uranium metal in the three different phases ({alpha}, {beta} and {gamma}) are compared by using BASTIEN-PORTEVIN method. The different experiments are testing the behaviour metal in each phase under different stresses and a temperature gradient as slow and shock traction, slow and shock compression, resilience, flexibility. Results show that optimum conditions for uranium drawing is uranium in phase {gamma}. In a second part, it described the drawing method and process. The uranium rods obtained by this technique are of very good quality. In addition, the material wear is very low which permits a low production cost. Finally, the uranium rod physical properties are studied. (M.P.)

Uranium

International Nuclear Information System (INIS)

Poty, B.; Cuney, M.; Bruneton, P.; Virlogeux, D.; Capus, G.

2010-01-01

With the worldwide revival of nuclear energy comes the question of uranium reserves. For more than 20 years, nuclear energy has been neglected and uranium prospecting has been practically abandoned. Therefore, present day production covers only 70% of needs and stocks are decreasing. Production is to double by 2030 which represents a huge industrial challenge. The FBR-type reactors technology, which allows to consume the whole uranium content of the fuel, is developing in several countries and will ensure the long-term development of nuclear fission. However, the implementation of these reactors (the generation 4) will be progressive during the second half of the 21. century. For this reason an active search for uranium ores will be necessary during the whole 21. century to ensure the fueling of light water reactors which are huge uranium consumers. This dossier covers all the aspects of natural uranium production: mineralogy, geochemistry, types of deposits, world distribution of deposits with a particular attention given to French deposits, the exploitation of which is abandoned today. Finally, exploitation, ore processing and the economical aspects are presented. Contents: 1 - the uranium element and its minerals: from uranium discovery to its industrial utilization, the main uranium minerals (minerals with tetravalent uranium, minerals with hexavalent uranium); 2 - uranium in the Earth's crust and its geochemical properties: distribution (in sedimentary rocks, in magmatic rocks, in metamorphic rocks, in soils and vegetation), geochemistry (uranium solubility and valence in magmas, uranium speciation in aqueous solution, solubility of the main uranium minerals in aqueous solution, uranium mobilization and precipitation); 3 - geology of the main types of uranium deposits: economical criteria for a deposit, structural diversity of deposits, classification, world distribution of deposits, distribution of deposits with time, superficial deposits, uranium

Study of uranium leaching from industrial residues of Industrias Nucleares do Brazil S.A. (INB), Caetite, Bahia, Brazil

International Nuclear Information System (INIS)

Formiga, Thiago S.; Morais, Carlos A.; Gomiero, Luiz A.

2011-01-01

The uraniferous district of Lagoa Real, located in the south-central region of the state of Bahia, has reserves estimated at 100,000 tons of uranium, which is enough to supply Angra I, II and III for 100 more years. The process adopted for the beneficiation of the uranium ore from Lagoa Real is heap leaching, a static process in which the ore is crushed, disposed in heaps and irrigated with a sulfuric acid solution to remove the uranium. This technique has a relatively low cost of implementation, although the yield of uranium recovery is low, with an uranium content in the leached residue of 700 μg/g U 3 O 8 for ores with an initial content of 2,700 μg/g U 3 O 8 . With the deepening of the mine pit, an increase in the carbonate content in the ore was noted, which required a higher acid consumption in the leaching. In order to reduce the concentration of carbonates, a study of the ore concentration by flotation column was accomplished. The flotation reject had high carbonate content, with a uranium content of about 2,300 μg/g U 3 O 8 for flotation in one column and 1,100 μg/g U 3 O 8 for flotation in two columns. This paper presents the study of the leaching process for the recovery of the uranium present in the residue of the heap leaching and in the carbonated residue from the flotation of the anomaly 13 ore. The results indicate the feasibility of treating the waste of the heap leaching through dynamic leaching. The study of the uranium leaching from the flotation residue through acid leaching technique indicated a recovery of 96% of uranium, however with a high consumption of acid, around 450 kg/t, showing that for this case, the most suitable technique for the process is alkaline leaching. (author)

Study of uranium leaching from industrial residues of Industrias Nucleares do Brazil S.A. (INB), Caetite, Bahia, Brazil

Energy Technology Data Exchange (ETDEWEB)

Formiga, Thiago S.; Morais, Carlos A., E-mail: cmorais@cdtn.b [Centro de Desenvolvimento da Tecnologia Nuclear (CDTN/CNEN-MG), Belo Horizonte, MG (Brazil); Gomiero, Luiz A., E-mail: gomiero@inb.gov.b [Industrias Nucleares do Brasil S/A (INB), Caetite, BA (Brazil)

2011-07-01

The uraniferous district of Lagoa Real, located in the south-central region of the state of Bahia, has reserves estimated at 100,000 tons of uranium, which is enough to supply Angra I, II and III for 100 more years. The process adopted for the beneficiation of the uranium ore from Lagoa Real is heap leaching, a static process in which the ore is crushed, disposed in heaps and irrigated with a sulfuric acid solution to remove the uranium. This technique has a relatively low cost of implementation, although the yield of uranium recovery is low, with an uranium content in the leached residue of 700 {mu}g/g U{sub 3}O{sub 8} for ores with an initial content of 2,700 {mu}g/g U{sub 3}O{sub 8}. With the deepening of the mine pit, an increase in the carbonate content in the ore was noted, which required a higher acid consumption in the leaching. In order to reduce the concentration of carbonates, a study of the ore concentration by flotation column was accomplished. The flotation reject had high carbonate content, with a uranium content of about 2,300 {mu}g/g U{sub 3}O{sub 8} for flotation in one column and 1,100 {mu}g/g U{sub 3}O{sub 8} for flotation in two columns. This paper presents the study of the leaching process for the recovery of the uranium present in the residue of the heap leaching and in the carbonated residue from the flotation of the anomaly 13 ore. The results indicate the feasibility of treating the waste of the heap leaching through dynamic leaching. The study of the uranium leaching from the flotation residue through acid leaching technique indicated a recovery of 96% of uranium, however with a high consumption of acid, around 450 kg/t, showing that for this case, the most suitable technique for the process is alkaline leaching. (author)

Anomalies

International Nuclear Information System (INIS)

Bardeen, W.A.

1985-08-01

Anomalies have a diverse impact on many aspects of physical phenomena. The role of anomalies in determining physical structure from the amplitude for π 0 decay to the foundations of superstring theory will be reviewed. 36 refs

Uranium mineralization at Lagoa Real, BA, Brazil: the role of fluids in its genesis

International Nuclear Information System (INIS)

Prates, Sonia Pinto; Neves, Jose Marques Correia; Fuzikawa, Kazuo

2009-01-01

The Lagoa Real uranium province is situated in the central-south of Bahia state . Brazil and it is presently by far the most important and best known uranium occurrence in Brazil. Nowadays 34 anomalies are known in a 30 Km long and 5 km wide area. An open pit mine was open in Cachoeira Mine, in the north portion of the area, and it is the only uranium mine in operation in Brazil and even in South America as well. The uranium mineralization in the Lagoa Real uranium province occurs in metamorphic rocks named albitites, due to their albite content (over 70%). Uraninite is the main uranium mineral, followed by pechblende, uranophane, torbernite and other uranyl minerals. Uraninite occurs as tiny round and irregular crystals (20 a 30 μm) included or associated to mafic minerals, mainly pyroxene and garnet, and also to amphibole and biotite and sometimes to albite. Some secondary minerals such as, for instance, uranophane, torbernite and tyuyamunite are also found. The main albitites minerals from the Cachoeira mine (plagioclase, garnet, biotite, pyroxene, amphibole and titanite) were studied by means of Infrared Spectroscopy Techniques. Good results were obtained from small quantities of material (around 2 mg) and allowed the minerals identification, and also to know their composition (from the peak position) and to detect the presence of water molecules, which indicates an aqueous phase during the uranium formation, probably rich in Fluorine. (author)

Investigation of the application of 4He/36Ar ratio and 222Rn measurements to the exploration for uranium mineral deposits. Final report

International Nuclear Information System (INIS)

Schutz, D.F.

1981-06-01

The sites of three uranium ore deposits of diverse geologic settings have been studied by a limited sampling of near-surface and subsurface soil gas, soil, and core materials to determine whether the uranium decay products 226 Ra, 222 Rn, 210 Pb, and 4 He may be useful as indicators of subsurface uranium mineralization. It was concluded that in the near-surface environment of all three sites, the 222 Rn levels were less than would be expected from closed system equilibrium with the soil itself and any anomalies with the underlying ore is fortuitous and does not provide a basis for guiding an exploration drilling operation. In contrast to the results for 222 Rn, the results for adsorbed 210 Pb show a number of locations with 210 Pb concentrations in the near-surface environment in excess of that expected from closed systems accumulations. However, the value of 210 Pb measurements as indicators of subsurface uranium deposits is considered inconclusive by the author. Radium-226 distributions in the near-surface samples at the three sites do not show significant patterns that are related to underlying ore. Most soil-gas samples have 4 He/ 36 Ar ratios significantly in excess of atmospheric levels. However, the lack of consistent relation to uranium mineralization either in areal or vertical distribution, coupled with the ability to measure excess 4 He in soils not associated in any way with uranium mineralization leads to the interpretation that much, if not all of the excess 4 He measured in soil gas is the result of in situ formation and not from allogenic sources

Preliminary evaluations of social and environmental impacts from mine-industrial project - uranium of Lagoa Real, Bahia, Brazil

International Nuclear Information System (INIS)

Negrao, F.I.; Oliveira, G.G. de; Zanetti, J.C.; Cunha, R.P.P. da.

1990-01-01

The Uranium Province of Lagoa Real is situated in the central south of the State of Bahia and constitutes at the moment the second uranium resource of Brazil, containing, in several anomalies, as available resource, 93.850 ton. of U sub(3) O sub(8). The Uranio do Brasil S.A. develops a mine-industrial complex in this Province with the aim to extract and benefit uranium and intending to improve in 1992. The project is considered with high hazard, because involves te management of radioactive material, and becomes necessary an available of environmental impact, in accordance with CONAMA 001/86 and an active participation of the society. This paper aims to indentify the social and environmental impacts of this process, as a contribution of this important discussion. (author)

The opportunities for uranium development in South Australia

International Nuclear Information System (INIS)

Jackson, N.

1979-07-01

The opportunities for uranium development in South Australia are discussed. The author outlines the likely development of three known uranium deposits, shows the world energy and uranium requirements and makes some observations on uranium enrichment

Intracranial developmental venous anomaly: is it asymptomatic?

Science.gov (United States)

Puente, A Bolívar; de Asís Bravo Rodríguez, F; Bravo Rey, I; Romero, E Roldán

2018-03-16

Intracranial developmental venous anomalies are the most common vascular malformation. In the immense majority of cases, these anomalies are asymptomatic and discovered incidentally, and they are considered benign. Very exceptionally, however, they can cause neurological symptoms. In this article, we present three cases of patients with developmental venous anomalies that presented with different symptoms owing to complications derived from altered venous drainage. These anomalies were located in the left insula, right temporal lobe, and cerebellum. The exceptionality of the cases presented as well as of the images associated, which show the mechanism through which the symptoms developed, lies in the low incidence of symptomatic developmental venous anomalies reported in the literature. Copyright © 2018 SERAM. Publicado por Elsevier España, S.L.U. All rights reserved.

Uranium control in phosphogypsum

International Nuclear Information System (INIS)

Hurst, F.J.; Arnold, W.D.

1980-01-01

In wet-process phosphoric acid plants, both previous and recent test results show that uranium dissolution from phosphate rock is significantly higher when the rock is acidulated under oxidizing conditions than under reducing conditions. Excess sulfate and excess fluoride further enhance the distribution of uranium to the cake. Apparently the U(IV) present in the crystal lattice of the apatite plus that formed by reduction of U(IV) by FE(II) during acidulation is trapped or carried into the crystal lattice of the calcium sulfate crystals as they form and grow. The amount of uranium that distributes to hemihydrate filter cake is up to seven times higher than the amount that distributes to the dihydrate cake. About 60% of the uranium in hemihydrate cakes can be readily leached after hydration of the cake, but the residual uranium (20 to 30%) is very difficult to remove economically. Much additional research is needed to develop methods for minimizing uranium losses to calcium filter cakes

Uranium resources and supply

International Nuclear Information System (INIS)

Cameron, J.

1973-01-01

The future supply of uranium has to be considered against a background of forecasts of uranium demand over the next decades which show increases of a spectacular nature. It is not necessary to detail these forecasts, they are well known. A world survey by the Joint NEA/IAEA Working Party on 'Uranium Resources, Production and Demand', completed this summer, indicates that from a present production level of just over 19,000 tonnes uranium per year, the demand will rise to the equivalent of an annual production requirement of 50,000 tonnes uranium by 1980, 100,000 by 1985 and 180,000 by 1990. Few, if any, mineral production industries have been called upon to plan for a near tenfold increase in production in a space of about 15 years as these forecasts imply. This might possibly mean that, perhaps, ten times the present number of uranium mines will have to be planned and engineered by 1990

The migration of uranium through sandstone

International Nuclear Information System (INIS)

Bennett, D.G.; Read, D.; Lawless, T.A.; Sims, R.J.

1992-01-01

Three column experiments are described in which the migration of uranium through Clashach Sandstone was studied. A priori predictions of uranium migration in the experiments were made using an equilibrium chemical transport model. The experimental results showed that, even under oxidising conditions, the migration of uranium is strongly retarded owing to the affinity of uranium for mineral surfaces. For the relatively simple chemical system investigated, the chemical transport model was successful in predicting the migration of uranium and its distribution along the column. (author)

Uranium Processing Research in Australia [Processing of Low-Grade Uranium Ores

Energy Technology Data Exchange (ETDEWEB)

Stewart, J R [Australian Atomic Energy Commission, Coogee, N.S.W. (Australia)

1967-06-15

Uranium processing research in Australia has included studies of flotation, magnetic separation, gravity separation, heavy medium separation, atmospheric leaching, multi-stage leaching, alkali leaching, solar heating of leach pulps, jigged-bed resin-in-pulp and solvent-in-pulp extraction. Brief details of the results obtained are given. In general, it can be said that gravity, magnetic and flotation methods are of limited usefulness in the treatment of Australian uranium ores. Alkali leaching seldom gives satisfactory recoveries and multi-stage leaching is expensive. Jigged-bed resin-in-pulp and packed tower solvent-in-pulp extraction systems both show promise, but plant-scale development work is required. Bacterial leaching may be useful in the case of certain low-grade ores. The main difficulties to be overcome, either singly or in combination, in the case of Australian uranium ores not currently considered economically exploitable, are the extremely finely divided state of the uranium mineral, the refractory nature of the uranium mineral and adverse effects due to the gangue minerals present. With respect to known low-grade ores, it would be possible in only a few cases to achieve satisfactory recovery of uranium at reasonable cost by standard treatment methods. (author)

Continued Multicolumns Bioleaching for Low Grade Uranium Ore at a Certain Uranium Deposit

OpenAIRE

Gongxin Chen; Zhanxue Sun; Yajie Liu

2016-01-01

Bioleaching has lots of advantages compared with traditional heap leaching. In industry, bioleaching of uranium is still facing many problems such as site space, high cost of production, and limited industrial facilities. In this paper, a continued column bioleaching system has been established for leaching a certain uranium ore which contains high fluoride. The analysis of chemical composition of ore shows that the grade of uranium is 0.208%, which is lower than that of other deposits. Howev...

Uranium conversion

International Nuclear Information System (INIS)

Oliver, Lena; Peterson, Jenny; Wilhelmsen, Katarina

2006-03-01

FOI, has performed a study on uranium conversion processes that are of importance in the production of different uranium compounds in the nuclear industry. The same conversion processes are of interest both when production of nuclear fuel and production of fissile material for nuclear weapons are considered. Countries that have nuclear weapons ambitions, with the intention to produce highly enriched uranium for weapons purposes, need some degree of uranium conversion capability depending on the uranium feed material available. This report describes the processes that are needed from uranium mining and milling to the different conversion processes for converting uranium ore concentrate to uranium hexafluoride. Uranium hexafluoride is the uranium compound used in most enrichment facilities. The processes needed to produce uranium dioxide for use in nuclear fuel and the processes needed to convert different uranium compounds to uranium metal - the form of uranium that is used in a nuclear weapon - are also presented. The production of uranium ore concentrate from uranium ore is included since uranium ore concentrate is the feed material required for a uranium conversion facility. Both the chemistry and principles or the different uranium conversion processes and the equipment needed in the processes are described. Since most of the equipment that is used in a uranium conversion facility is similar to that used in conventional chemical industry, it is difficult to determine if certain equipment is considered for uranium conversion or not. However, the chemical conversion processes where UF 6 and UF 4 are present require equipment that is made of corrosion resistant material

Round robin 'Impurities in uranium matrix': a success for CETAMA and IAEA

International Nuclear Information System (INIS)

Granier, Guy; Roudil, Daniele; Balsley, Steven Devry; Bulyha, Siarhei; Aregbe, Yetunde

2012-01-01

The safeguard of nuclear material is of paramount importance to the IAEA which increasingly uses this information for characterization purposes in order to strengthen the verification of declared nuclear material and to identify the origin of samples from mines. IAEA tasked CETAMA to conduct a round robin with objective to evaluate the capability of laboratories to measure impurities in uranium with concentration levels between 1 and 500 ppm relative to uranium. This round robin was attended by 17 international laboratories from the nuclear industry and safeguards community. The results are mainly obtained by ICP-MS and ICP-AES. The synthesis of this round robin were helpful in identifying anomalies and will allow the IAEA to better set realistic measurement performance targets for ICP-MS and ICP-AES. (authors)

The significance of zircon characteristic and its uranium concentration in evaluation of uranium metallogenetic prospect

International Nuclear Information System (INIS)

Li Yaosong; Zhu Jiechen; Xia Yuliang

1992-02-01

Zircon characteristic and its relation to uranium metallogenetic process have been studied on the basis of physics properties and chemical compositions. It is indicated that the colour of zircon crystal is related to uranium concentration; on the basis of method of zircon population type of Pupin J.P., the sectional plan of zircon population type has been designed, from which result that zircon population type of uranium-producing rock body is distributed mainly in second section, secondly in fourth section; U in zircon presents synchronous increase trend with Th, Hf and Ta; the uranium concentration in zircon from uranium-producing geologic body increases obviously and its rate of increase is more than that of the uranium concentration in rock; the period, in which uranium concentration in zircon is increased, is often related to better uranium-producing condition in that period of this area. 1785 data of the average uranium concentration in zircon have been counted and clear regularity has been obtained, namely the average uranium concentrations in zircon in rich uranium-producing area, rock, geologic body and metallogenetic zone are all higher than that in poor or no uranium-producing area, rock, geologic body and metallogenetic zone. This shows that the average uranium concentration in zircon within the region in fact reflects the primary uranium-bearing background in region and restricts directly follow-up possibility of uranium mineralization. On the basis of this, the uranium source conditions of known uranium metallogenetic zones and prospective provinces have been discussed, and the average uranium concentrations in zircon from magmatic rocks for 81 districts have been contrasted and graded, and some districts in which exploration will be worth doing further are put forward

Machining of uranium and uranium alloys

International Nuclear Information System (INIS)

Morris, T.O.

1981-01-01

Uranium and uranium alloys can be readily machined by conventional methods in the standard machine shop when proper safety and operating techniques are used. Material properties that affect machining processes and recommended machining parameters are discussed. Safety procedures and precautions necessary in machining uranium and uranium alloys are also covered. 30 figures

Spectral anomaly methods for aerial detection using KUT nuisance rejection

International Nuclear Information System (INIS)

Detwiler, R.S.; Pfund, D.M.; Myjak, M.J.; Kulisek, J.A.; Seifert, C.E.

2015-01-01

This work discusses the application and optimization of a spectral anomaly method for the real-time detection of gamma radiation sources from an aerial helicopter platform. Aerial detection presents several key challenges over ground-based detection. For one, larger and more rapid background fluctuations are typical due to higher speeds, larger field of view, and geographically induced background changes. As well, the possible large altitude or stand-off distance variations cause significant steps in background count rate as well as spectral changes due to increased gamma-ray scatter with detection at higher altitudes. The work here details the adaptation and optimization of the PNNL-developed algorithm Nuisance-Rejecting Spectral Comparison Ratios for Anomaly Detection (NSCRAD), a spectral anomaly method previously developed for ground-based applications, for an aerial platform. The algorithm has been optimized for two multi-detector systems; a NaI(Tl)-detector-based system and a CsI detector array. The optimization here details the adaptation of the spectral windows for a particular set of target sources to aerial detection and the tailoring for the specific detectors. As well, the methodology and results for background rejection methods optimized for the aerial gamma-ray detection using Potassium, Uranium and Thorium (KUT) nuisance rejection are shown. Results indicate that use of a realistic KUT nuisance rejection may eliminate metric rises due to background magnitude and spectral steps encountered in aerial detection due to altitude changes and geographically induced steps such as at land–water interfaces

Uranium, depleted uranium, biological effects; Uranium, uranium appauvri, effets biologiques

Energy Technology Data Exchange (ETDEWEB)

NONE

2001-07-01

Physicists, chemists and biologists at the CEA are developing scientific programs on the properties and uses of ionizing radiation. Since the CEA was created in 1945, a great deal of research has been carried out on the properties of natural, enriched and depleted uranium in cooperation with university laboratories and CNRS. There is a great deal of available data about uranium; thousands of analyses have been published in international reviews over more than 40 years. This presentation on uranium is a very brief summary of all these studies. (author)

Recovery of uranium and molybdenum from a carbonate type uranium-molybdenum ore

International Nuclear Information System (INIS)

Zhou Genmao; Zeng Yijun; Tang Baobin; Meng Shu; Xu Guolong

2014-01-01

Based on the results of process mineralogical research of a carbonate type uranium-molybdenum ore, leaching behaviors of the uranium-molybdenum ore were studied by alkali agitation leaching, conventional alkali column leaching and alkali curing column leaching processes. The results showed that using the alkali curing column leaching process, the leaching rate of molybdenum increased to more than 90%, and the leaching rate of uranium was about 85%, Compared with the conventional alkali column leaching process, the leaching time of the alkali curing column leaching process decreased by 60 days. (authors)

The concentrations of uranium in marine organisms

Energy Technology Data Exchange (ETDEWEB)

Matsuba, Mitsue; Ishii, Toshiaki; Nakahara, Motokazu; Nakamura, Ryoichi; Watabe, Teruhisa; Hirano, Shigeki [National Inst. of Radiological Sciences, Hitachinaka, Ibaraki (Japan). Laboratory for Radioecology

2000-07-01

Determination of uranium in sixty-one species of marine organisms was carried out by inductively coupled plasma mass spectrometry to obtain concentration factors and to estimate the internal radiation dose. The concentrations of uranium in soft tissues of marine animals were ranged from 0.077 to 5040 ng/g wet wt. Especially, the branchial heart of cephalopod molluscs showed the specific accumulation of uranium. The concentration factor of the branchial heart of Octopus vulgaris, which indicated the highest value, was calculated to be about 1.6 x 10{sup 3}, comparing with that (3.1 ng/ml) in coastal seawaters of Japan. The concentrations of uranium in hard tissues of marine invertebrates such as clam and sea urchin were similar to those in soft tissues. In contrast, hard tissues like bone, scale, fin, etc. of fishes showed much higher concentrations of uranium than soft tissues like muscle. The concentrations of uranium of twenty-two species of algae were ranged from 2 to 310 ng/g wet wt. Particularly, the brown alga Undaria pinnatifida showed the highest value of the uranium content in the algae and its concentration factor was calculated to be 10{sup 2}. (author)

The concentrations of uranium in marine organisms

International Nuclear Information System (INIS)

Matsuba, Mitsue; Ishii, Toshiaki; Nakahara, Motokazu; Nakamura, Ryoichi; Watabe, Teruhisa; Hirano, Shigeki

2000-01-01

Determination of uranium in sixty-one species of marine organisms was carried out by inductively coupled plasma mass spectrometry to obtain concentration factors and to estimate the internal radiation dose. The concentrations of uranium in soft tissues of marine animals were ranged from 0.077 to 5040 ng/g wet wt. Especially, the branchial heart of cephalopod molluscs showed the specific accumulation of uranium. The concentration factor of the branchial heart of Octopus vulgaris, which indicated the highest value, was calculated to be about 1.6 x 10 3 , comparing with that (3.1 ng/ml) in coastal seawaters of Japan. The concentrations of uranium in hard tissues of marine invertebrates such as clam and sea urchin were similar to those in soft tissues. In contrast, hard tissues like bone, scale, fin, etc. of fishes showed much higher concentrations of uranium than soft tissues like muscle. The concentrations of uranium of twenty-two species of algae were ranged from 2 to 310 ng/g wet wt. Particularly, the brown alga Undaria pinnatifida showed the highest value of the uranium content in the algae and its concentration factor was calculated to be 10 2 . (author)

Development of on-line uranium enrichment monitor of gaseous UF6 for uranium enrichment plant

International Nuclear Information System (INIS)

Lu Xuesheng; Liu Guorong; Jin Huimin; Zhao Yonggang; Li Jinghuai; Hao Xueyuan; Ying Bin; Yu Zhaofei

2013-01-01

An on-line enrichment monitor was developed to measure the enrichment of UF 6 , flowing through the processing pipes in uranium enrichment plant. A Nal (Tl) detector was used to measure the count rates of the 185.7 keV γ-ray emitted from 235 U, and the total quantity of uranium was determined from thermodynamic characteristics of gaseous uranium hexafluoride. The results show that the maximum relative standard deviation is less than 1% when the measurement time is 120 s or more and the pressure is more than 2 kPa in the measurement chamber. Uranium enrichment of gaseous uranium hexafluoride in the output end of cascade can be monitored continuously by using the device. It should be effective for nuclear materials accountability verifications and materials balance verification at uranium enrichment plant. (authors)

Comparison of estimation and simulation methods for modeling block 1 of anomaly no.3 in Narigan Uranium mineral deposit

International Nuclear Information System (INIS)

Jamali Esfahlan, D.; Madani, H.

2011-01-01

Geostatistical methods are applied for modeling the mineral deposits at the final stage of the detailed exploration. By applying the results of these models, the technical and economic feasibility studies are conducted for the deposits. The geostatistical modeling methods are usually consist of estimation and simulation methods. The estimation techniques, such as Kriging, construct spatial relation (geological continuation model) between data, by providing the best unique guesses for unknown features. However, when applying this technique for a grid of drill-holes over a deposit, an obvious discrepancy exists between the real geological features and the Kriging estimation map. Because of the limited number of sampled data applied for Kriging, it could not appear as the same as the real features. Also the spatial continuity estimated by the Kriging maps, are smoother than the real unknown features. On the other hand, the objective of simulation is to provide some functions or sets of variable values, to be compatible with the existing information. This means that the simulated values have an average and the variance similar to the raw data and may even be the same as the measurements. we studied the Anomaly No.3 of Narigan uranium mineral deposit, located in the central Iran region and applied the Kriging estimation and the sequential Gaussian simulation methods, and finally by comparing the results we concluded that the Kriging estimation method is more reliable for long term planning of a mine. Because of the reconstructing random structures, the results of the simulation methods indicate that they could also be applied for short term planning in mine exploitation.

Global gravitational anomalies and transport

Energy Technology Data Exchange (ETDEWEB)

Chowdhury, Subham Dutta; David, Justin R. [Centre for High Energy Physics, Indian Institute of Science,C. V. Raman Avenue, Bangalore 560012 (India)

2016-12-21

We investigate the constraints imposed by global gravitational anomalies on parity odd induced transport coefficients in even dimensions for theories with chiral fermions, gravitinos and self dual tensors. The η-invariant for the large diffeomorphism corresponding to the T transformation on a torus constraints the coefficients in the thermal effective action up to mod 2. We show that the result obtained for the parity odd transport for gravitinos using global anomaly matching is consistent with the direct perturbative calculation. In d=6 we see that the second Pontryagin class in the anomaly polynomial does not contribute to the η-invariant which provides a topological explanation of this observation in the ‘replacement rule’. We then perform a direct perturbative calculation for the contribution of the self dual tensor in d=6 to the parity odd transport coefficient using the Feynman rules proposed by Gaumé and Witten. The result for the transport coefficient agrees with that obtained using matching of global anomalies.

Research on uranium and thorium elements exploration through the study of petrography, petrology and geophysical method in the Saghand Area (Central Iran) Islamic Republic of Iran

International Nuclear Information System (INIS)

Iranmanesh, J.; Fattahi, V.; Raziani, S.

2014-01-01

This study is a research on uranium and thorium exploration by use of the petrography, petrology and radiometric data in the Saghand area, Central Iran plateau. The lithologies of this area comprise of granite and metasomatized granite. As a result of metasomatic process, uranium and thorium bearing minerals such as davidite and alanite were formed. Sericitization and albitization are the main alterations detected in the study area and thorium mineralization is more common in albitization. By investigation of the chemical classification, non-radioactive specimens, rock types include: diorite and granodiorite, while radioactive specimens consist of gabbroic rocks (basalt). According to the magma source graphs, these rocks formed by calc-alkaline series magma. A scintillometer and spectrometer (MGS-150) were used for radiometric data acquisition. 1001 data points have been obtained from 11 profiles and total counts for, K, U, Th were measured. After primary data processing, data logarithms were calculated for normalizing, and the radiometric data show that uranium and thorium enrichment is more than potassium, while thorium and uranium enrichment are approximately equal. After data integration, two probable anomalies were determined in northwest and northeast parts of the study area. (author)

Developments in uranium in 1986

International Nuclear Information System (INIS)

Chenoweth, W.L.

1987-01-01

Imported uranium and low prices continued to plague the domestic uranium industry and, as a result, the Secretary of Energy declared the domestic industry to be nonviable for the second straight year. Uranium exploration expenditures in the US declined for the eighth consecutive year. In 1986, an estimated $19 million was spent on uranium exploration, including 1.9 million ft of surface drilling. This drilling was done mainly in producing areas and in areas of recent discoveries. Production of uranium concentrate increased in 1986, when 13.8 million lb of uranium oxide (U 3 O 8 ) were produced, a 22% increase over 1985. Uranium produced as the result of solution mining and as the by-product of phosphoric acid production accounted for about 37% of the total production in the US. At the end of 1986, only 6 uranium mills were operating in the US. Canada continued to dominate the world market. The development under way at the huge Olympic Dam deposit in Australia will increase that country's production. US uranium production is expected to show a small decrease in 1987. 3 figures, 2 tables

Evaluation of Uranium depositional system in sedimentary rocks of Sibolga formation, Tapanuli Tengah

International Nuclear Information System (INIS)

I Gde Sukadana; Heri Syaeful

2016-01-01

Uranium in nature formed in various deposit type, depends on its sources, process, and depositional environments. Uranium occurrence in Sibolga, hosted in sedimentary rocks of Sibolga Formation, is properly potential to develop; nevertheless, the depositional pattern and uranium mineralization process so far had not been recognized. The research aim is to determine the rock distribution patterns and the existence of uranium grade anomalies based on surface geology and borehole log data. Mineralization occurrences from borehole log data distributed from basalt conglomerate unit (Kgl 1), sandstone 1 unit (Bp 1), conglomerate 2 unit (Kgl 2), and sandstone 2 unit (Bp 2) with their distribution and thickness are thinning to the top. Mineralization distribution in the eastern area, mainly on Kgl 1 unit, dominated by detritus materials from epi-genetic depositional in the form of monazite which is formed along with the formation of granite as its source rock. Meanwhile, mineralization on the upper rocks units formed a channel pattern trending northeast-southwest, which formed in syn-genetic process consist of uraninite, carnotite, and coffinite. Sibolga Formation deposition originated from east to west and uranium deposit formed because of the differences of depositional environment from oxidation in the east to the more reductive in the southwest. The increasing of organic materials in southwest basin caused the reduction condition of depositional environment. (author)

Distribution of uranium supply and enrichment

International Nuclear Information System (INIS)

Bamford, F.W.

1982-01-01

Uranium supply and demand is examined from the perspective of companies in the uranium hexafluoride (UF6) conversion business whose main interest is their sources of uranium supply and UF6 destinations because of transportation costs. Because of the variations in yellowcake transport, charges for conversion, and UF6 transport costs, most converters don't have standard prices. Companies try to look ahead to determine patterns of supplies and delivery points when they analyze the market and estimate future prices. Market analyses must take into account the purchasing policies of utilities around the world. The presentation shows North America supplying about 40% of world uranium, with about 13% of the enrichment done elsewhere. It also shows North American converters getting 53% of the business, but that will require importing uranium from outside North America. 6 tables

Multi-column bioleaching of a uranium ore

International Nuclear Information System (INIS)

Meng Yunsheng; Zheng Ying; Liu Hui; Cheng Hao

2014-01-01

The technology of bioleaching uranium ore can increase the uranium leaching rate and shorten the leaching uranium period, save consumption of acid and oxidant, lower production costs. An experiment on multi-column bioleaching of a uranium ore was done using mesophilic bacteria, the average uranium recovery of 90% was achieved in 39 days. Compared with traditional process, leaching period was shortened to 39 d from 59 d, acid consumption and liquid-solid ratio were also reduced. The results showed it is suitable to bioleach the uranium ore. (authors)

Recovery and treatment of uranium from uranium-containing solution by liquid membrane emulsion technology

International Nuclear Information System (INIS)

Xia Liangshu; Zhou Yantong; Xiao Yiqun; Peng Anguo; Xiao Jingshui; Chen Wei

2014-01-01

The recovery and treatment of uranium from uranium-containing solution using liquid membrane emulsion (LME) technology were studied in this paper, which contained the best volume ratio of membrane materials, stirring speed during emulsion process, the conditions of extracting, such as temperature, pH, initial concentration of uranium. Moreover, the mechanism for extracting uranium was also discussed. The best experimental conditions of emulsifying were acquired. The volume fractions of P 204 and liquid paraffin are 0.1 and 0.05, the volume ratios of Span80 and sulphonated kerosene to P 204 are 0.06 and 0.79 respectively, stirring speed is controlled in 2 000 r/min, and the concentration of inner phase is 4 mol/L. The recovery rate of uranium is up to 99% through the LME extracted uranium for 0.5 h at pH 2.5 and room temperature when the initial concentration is less than 400 mg/L and the volume ratio is 5 between the uranium-containing waste water and LME. The calculation results of Gibbs free energy show that the reaction process is spontaneous. (authors)

Preliminary study of uranium favorability of the Wilcox and Claiborne Groups (Eocene) in Texas

International Nuclear Information System (INIS)

Wilbert, W.P.; Templain, C.J.

1978-01-01

Rocks of the Wilcox and Claiborne Groups crop out in the Texas Gulf Coastal Plain and are represented by a series of sands and shales which reflect oscillation of the strandline. The Wilcox Group (lower Eocene), usually undifferentiated in Texas, consists of very fine sands and clays and abundant lignite. The Claiborne Group (middle Eocene) comprises, in ascending order, Carrizo Sand, Reklaw Formation (clay), Queen City Sand, Weches Formation (clay), Sparta Sand, Cook Mountain Formation (clay), and Yegua Formation (sand). Fluvial systems of the Wilcox and Claiborne Groups exist in east Texas and trend perpendicular to the present coastline. In central Texas, sand bodies are parallel to the present coastline and are strand-plain, barrier-bar systems. Since the time of deposition of the Queen City Sand, a significant fluvial sand buildup occurred in the area of the present Rio Grande embayment where the marine clays pinch out. Known occurrences of mineral matter in the Wilcox and Claiborne (up to the Yegua) are limited to lignite (particularly in the Wilcox), cannel coal in the upper Claiborne, and hydrocarbons throughout. No uranium mineralization is known, and no uranium is likely to be discovered in the Claiborne and Wilcox. Approximately 50 surface samples and many gamma-ray logs showed no significant anomalies. The sands are very good potential host rocks, but no uranium source was discovered. During deposition of the Wilcox and Claiborne Groups, there was no volcanism to serve as a source of uranium (as with the prolific occurrences in the younger rocks of south Texas); also, Precambrian crystalline rocks in the Llano uplift were not exposed

Possible uranium sources of Streltsovsky uranium ore field

International Nuclear Information System (INIS)

Zhang Lisheng

2005-01-01

The uranium deposit of the Late Jurassic Streltsovaky caldera in Transbaikalia of Russia is the largest uranium field associated with volcanics in the world, its uranium reserves are 280 000 t U, and it is the largest uranium resources in Russia. About one third of the caldera stratigraphic pile consists of strongly-altered rhyolites. Uranium resources of the Streltsovsky caldera are much larger than any other volcanic-related uranium districts in the world. Besides, the efficiency of hydrothermal alteration, uranium resources appear to result from the juxtaposition of two major uranium sources; highly fractionated peralkaline rhyolites of Jurassic age in the caldera, and U-rich subalkaline granites of Variscan age in the basement in which the major uranium-bearing accessory minerals were metamict at the time of the hydrothermal ore formation. (authors)

Dimensional reduction in anomaly mediation

International Nuclear Information System (INIS)

Boyda, Ed; Murayama, Hitoshi; Pierce, Aaron

2002-01-01

We offer a guide to dimensional reduction in theories with anomaly-mediated supersymmetry breaking. Evanescent operators proportional to ε arise in the bare Lagrangian when it is reduced from d=4 to d=4-2ε dimensions. In the course of a detailed diagrammatic calculation, we show that inclusion of these operators is crucial. The evanescent operators conspire to drive the supersymmetry-breaking parameters along anomaly-mediation trajectories across heavy particle thresholds, guaranteeing the ultraviolet insensitivity

Anomaly depth detection in trans-admittance mammography: a formula independent of anomaly size or admittivity contrast

International Nuclear Information System (INIS)

Zhang, Tingting; Lee, Eunjung; Seo, Jin Keun

2014-01-01

Trans-admittance mammography (TAM) is a bioimpedance technique for breast cancer detection. It is based on the comparison of tissue conductivity: cancerous tissue is identified by its higher conductivity in comparison with the surrounding normal tissue. In TAM, the breast is compressed between two electrical plates (in a similar architecture to x-ray mammography). The bottom plate has many sensing point electrodes that provide two-dimensional images (trans-admittance maps) that are induced by voltage differences between the two plates. Multi-frequency admittance data (Neumann data) are measured over the range 50 Hz–500 kHz. TAM aims to determine the location and size of any anomaly from the multi-frequency admittance data. Various anomaly detection algorithms can be used to process TAM data to determine the transverse positions of anomalies. However, existing methods cannot reliably determine the depth or size of an anomaly. Breast cancer detection using TAM would be improved if the depth or size of an anomaly could also be estimated, properties that are independent of the admittivity contrast. A formula is proposed here that can estimate the depth of an anomaly independent of its size and the admittivity contrast. This depth estimation can also be used to derive an estimation of the size of the anomaly. The proposed estimations are verified rigorously under a simplified model. Numerical simulation shows that the proposed method also works well in general settings. (paper)

Process for continuous production of metallic uranium and uranium alloys

Science.gov (United States)

Hayden, Jr., Howard W.; Horton, James A.; Elliott, Guy R. B.

1995-01-01

A method is described for forming metallic uranium, or a uranium alloy, from uranium oxide in a manner which substantially eliminates the formation of uranium-containing wastes. A source of uranium dioxide is first provided, for example, by reducing uranium trioxide (UO.sub.3), or any other substantially stable uranium oxide, to form the uranium dioxide (UO.sub.2). This uranium dioxide is then chlorinated to form uranium tetrachloride (UCl.sub.4), and the uranium tetrachloride is then reduced to metallic uranium by reacting the uranium chloride with a metal which will form the chloride of the metal. This last step may be carried out in the presence of another metal capable of forming one or more alloys with metallic uranium to thereby lower the melting point of the reduced uranium product. The metal chloride formed during the uranium tetrachloride reduction step may then be reduced in an electrolysis cell to recover and recycle the metal back to the uranium tetrachloride reduction operation and the chlorine gas back to the uranium dioxide chlorination operation.

Process for continuous production of metallic uranium and uranium alloys

Science.gov (United States)

Hayden, H.W. Jr.; Horton, J.A.; Elliott, G.R.B.

1995-06-06

A method is described for forming metallic uranium, or a uranium alloy, from uranium oxide in a manner which substantially eliminates the formation of uranium-containing wastes. A source of uranium dioxide is first provided, for example, by reducing uranium trioxide (UO{sub 3}), or any other substantially stable uranium oxide, to form the uranium dioxide (UO{sub 2}). This uranium dioxide is then chlorinated to form uranium tetrachloride (UCl{sub 4}), and the uranium tetrachloride is then reduced to metallic uranium by reacting the uranium chloride with a metal which will form the chloride of the metal. This last step may be carried out in the presence of another metal capable of forming one or more alloys with metallic uranium to thereby lower the melting point of the reduced uranium product. The metal chloride formed during the uranium tetrachloride reduction step may then be reduced in an electrolysis cell to recover and recycle the metal back to the uranium tetrachloride reduction operation and the chlorine gas back to the uranium dioxide chlorination operation. 4 figs.

Uranium update

International Nuclear Information System (INIS)

Steane, R.

1997-01-01

This paper is about the current uranium mining situation, especially that in Saskatchewan. Canada has a unique advantage with the Saskatchewan uranium deposits. Making the most of this opportunity is important to Canada. The following is reviewed: project development and the time and capital it takes to bring a new project into production; the supply and demand situation to show where the future production fits into the world market; and our foreign competition and how we have to be careful not to lose our opportunity. (author)

Uranium fluoride and metallic uranium as target materials for heavy-element experiments at SHIP

Energy Technology Data Exchange (ETDEWEB)

Kindler, Birgit [Gesellschaft fuer Schwerionenforschung (GSI), Planckstrasse 1, D-64291 Darmstadt (Germany)], E-mail: b.kindler@gsi.de; Ackermann, Dieter; Hartmann, Willi; Hessberger, Fritz Peter; Hofmann, Sigurd; Huebner, Annett; Lommel, Bettina; Mann, Rido; Steiner, Jutta [Gesellschaft fuer Schwerionenforschung (GSI), Planckstrasse 1, D-64291 Darmstadt (Germany)

2008-06-01

In this contribution we describe the production and application of uranium targets for synthesis of heavy elements. The targets are prepared from uranium fluoride (UF{sub 4}) and from metallic uranium with thin carbon foils as backing. Targets of UF{sub 4} were produced by thermal evaporation in a similar way as the frequently applied targets out of Bi, Bi{sub 2}O{sub 3}, Pb, PbS, SmF{sub 3}, and NdF{sub 3,} prepared mostly from isotopically enriched material [Birgit Kindler, et al., Nucl. Instr. and Meth. A 561 (2006) 107; Bettina Lommel, et al., Nucl. Instr. and Meth. A 561 (2006) 100]. In order to use more intensive beams and to avoid scattering of the reaction products in the target, metallic uranium is favorable. However, evaporation of metallic uranium is not feasible at a sustainable yield. Therefore, we established magnetron sputtering of metallic uranium. We describe production and properties of these targets. First irradiation tests show promising results.

The role of solutions and uranium geochemistry in the geological formations of Jabal Abou-Rejmain-Northern Palmyrides

International Nuclear Information System (INIS)

Jubeli, Y.; Aissa, M.; Al-Hilall, M.

1999-09-01

The equivalent concentration of potassium, uranium, thorium and total radioactivity of various geological outcrops, along the major wadis of the southern and northern flanks of Jabal Abou-Rejmain, were determined. The radiometric anomalies found to be closely related to either phosphate beds of Companion age, or to spots of yellow secondary uranium minerals precipitated on very soft gray marly limestone rocks of Maestrichtian age. The present work indicates that phosphat deposition in the northern palmy rides seems to be widely distributed in the northern Patmyrides more than it was known earlier. The occurrences of secondary uranium mineralization coincide with the presence of evaporates, such as gypsum, which indicates that the precipitation occurs out of uranium enriched solution which were subjected to aridity and evaporation. The soft marly limestone rocks contains the highest percentage of clay fraction. This fraction is responsible for razing and absorbing the solutions, which were leached out of the Companion facies leading to precipitation of uranium minerals on the surface, as well as, within the pores of the rocks. However, transportation of these solutions, in the study area, seems not to extent for a long distance. (author

232Th/238U in a uranium mobility estimate in an agricultural area in the municipality of Pedra-Pernambuco - Brazil

International Nuclear Information System (INIS)

Santos Junior, Jose Araujo dos; Amaral, Romilton dos Santos; Bezerra, Jairo Dias; Damascena, Kennedy Francys Rodrigues; Oliveira, Jose Valdez Monterazo de; Bispo, Rodrigo Cesar Bezerra; Silva, Cleomacio Miguel da; Rocha, Edilson Accioly

2011-01-01

The mobility of the radionuclides in soil depends primarily on the physic-chemical parameters. The uranium is easily oxidized in aqueous environment, which allows its characterization with higher mobility. The Thorium is practically insoluble, mainly if the environment has organic matter and sulfates. The geochemical characteristics of the rocks, associated with the weather and metamorphism produce alterations in the concentration diagrams of the natural radionuclides in different types of soil. The ratio 232 Th/ 238 U has been used as an indicator of oxidizing and reducing conditions. Th/U less than 2 suggests that the uranium is in its concentrated form abundantly when compared to the thorium. In reducing conditions, the value Th/U higher than 7 indicates a removal of the uranium. In this work it was possible to analyze the agricultural soil in the municipality of Pedra, Pernambuco, Brazil where there are uranium anomaly and thorium in rocky outcrops. Sixty-two samples of the horizon C soil were collected, in an area of 2 km 2 , where the main uranium occurrences are located. The analyses were done by High-Resolution Gamma-Spectroscopy. In the analyses the secular equilibrium was assumed and the 238 U and the 232 Th specific activities were used to estimate the oxidizing and reducing conditions defining the uranium mobility in the soil. The obtained findings show that the ratio Th/U varied from 0.3 to 13.4, with average of 4.6. The biggest 238 U fraction was fix (80.3%), with low mobility; the smallest fraction concentrated (6.6%) and a lixiviated intermediate fraction (13.1%). (author)

Exploration of Uranium in Simpang Kanan, East Aceh, Preliminary Prospecting Stages

International Nuclear Information System (INIS)

Djalil, A; Sutriyono, A; Sajiyo

1998-01-01

Exploration of uranium in simpang kanan, east aceh, preliminary prospecting stages. The research has been carried out to obtain the knowledge of geology, radiometry and geochemistry in relation with U prospect development. Based on the similarity of lithology in takengon sector which indicates the existence of uranium mineralization. Research method consist of geological observation, radiometric measurements of outcrops, boulders and stream sediment and heavy mineral samples. Laboratory analysis consist of petrography, autoradiography and uranium content analysis of stream sediment and rock samples. The lithology consist of slate, quartzite, marble, granite, dacite, limestone, carbonaceous sandstone, black claystone, sandstone, siltstone, carbonaceous siltstone. This area found, has been folded with the folding axis direction of NW-SE. Fault structures are generally formed as strike slip fault and several location as normal fault and heavy minerals anomalous was interpreted from granite and sandstone- siltstone. Occurrences of the geochemical anomaly, lithology and geological structures, there has been shown that few location is being the prospect area covered about 70 km of 1800km prospecting area, so it is suggested that in those related prospect area should be performed further observation

Uranium prospect inventory on general prospection stage at Sigli sector Aceh

International Nuclear Information System (INIS)

Soetopo, Bambang; Sutriyono, Agus; Sajiyo

2002-01-01

This study based on the considering of the existence of reductive sedimentary rock and acid igneous rocks. The rocks could be favorable for uranium accumulation and source rocks respectively. The aim of this study is to understand the uranium geology, radiometric and geochemical anomalies distribution and it to delineate the prospective area to uranium accumulation. Method of this study field geological observations, radiometric measurements, stream sediment and heavy mineral concentrate sampling, mineralogical and geochemical laboratory analysis. Litho logically, the area composed of slate (Early Yurassic), schist and phyllite (Triassic) and meta calcareous marl (Cretaceous). Those rocks un conformably overly by black siltstone and sandstone (Eocene) conglomerate sandstone (Late Oligocene-Early Miocene) siltstone (Middle Miocene). Some intrusions have been identified as biotite granodiorite (Cretaceous) porphyritic granodiorite (Eocene) and Olivine basalt (Middle Miocene-late Miocene). The rock have been faulted by dextral strike slip fault NW-SE, thrust fault NW-SE, sinistral; strike slip fault NE-SW, and normal faults WNW-ESE. Radioactivity value of rocks range between 40-100 cps SPP2NF and it contains is range about 0.36-150.84 ppm U. The geochemical prospect area has been defined at the area of 93.186 km 2

The uranium potential of the continental Cretaceous of Patagonia

International Nuclear Information System (INIS)

Olsen, H.; Berizzo, J.

1980-01-01

The geological features of the fluvial sedimentation of the Cretaceous of Patagonia - the Grupo Chubut Formation in the provinces of Chubut and Santa Cruz, underlined this environment as one of high favourability for discovering uranium deposits. The area has been explored by the CNEA who found two outstanding levels of fluvial sediments that are today the target of further studies to find new deposits. The general geological features are given, together with the results of the exploration up to date, distribution of radiometric anomalies, deposits discovered and an estimation of the uraniferous potential of the Formation. (author)

Kohn anomaly in phonon driven superconductors

International Nuclear Information System (INIS)

Das, M P; Chaudhury, R

2014-01-01

Anomalies often occur in the physical world. Sometimes quite unexpectedly anomalies may give rise to new insight to an unrecognized phenomenon. In this paper we shall discuss about Kohn anomaly in a conventional phonon-driven superconductor by using a microscopic approach. Recently Aynajian et al.'s experiment showed a striking feature; the energy of phonon at a particular wave-vector is almost exactly equal to twice the energy of the superconducting gap. Although the phonon mechanism of superconductivity is well known for many conventional superconductors, as has been noted by Scalapino, the new experimental results reveal a genuine puzzle. In our recent work we have presented a detailed theoretical analysis with the help of microscopic calculations to unravel this mystery. We probe this aspect of phonon behaviour from the properties of electronic polarizability function in the superconducting phase of a Fermi liquid metal, leading to the appearance of a Kohn singularity. We show the crossover to the standard Kohn anomaly of the normal phase for temperatures above the transition temperature. Our analysis provides a nearly complete explanation of this new experimentally discovered phenomenon. This report is a shorter version of our recent work in JPCM.

Euro-African MAGSAT anomaly-tectonic observations

Science.gov (United States)

Hinze, W. J.; Olivier, R.; Vonfrese, R. R. B.

1985-01-01

Preliminary satellite (MAGSAT) scalar magnetic anomaly data are compiled and differentially reduced to radial polarization by equivalent point source inversion for comparison with tectonic data of Africa, Europe and adjacent marine areas. A number of associations are evident to constrain analyses of the tectonic features and history of the region. The Precambrian shields of Africa and Europe exhibit varied magnetic signatures. All shields are not magnetic highs and, in fact, the Baltic shield is a marked minimum. The reduced-to-the-pole magnetic map shows a marked tendency for northeasterly striking anomalies in the eastern Atlantic and adjacent Africa, which is coincident to the track of several hot spots for the past 100 million years. However, there is little consistency in the sign of the magnetic anomalies and the track of the hot spots. Comparison of the radially polarized anomalies of Africa and Europe with other reduced-to-the-pole magnetic satellite anomaly maps of the Western Hemisphere support the reconstruction of the continents prior to the origin of the present-day Atlantic Ocean in the Mesozoic Era.

Uranium leaching analysis (IAEA method) and total uranium determination in caldasite by the fluorometric method

International Nuclear Information System (INIS)

Sardela, I.A.; Fujimori, K.

1980-10-01

Caldasite is a radioactive mineral known mostly for its high radioactive content (U and Th). It is found only at the Pocos de Caldas Alkaline Complex, States of Minas Gerais. Samples colected at Campos do Serrote, Taquari and Brigrada located in the alkaline complex were submitted to the fluorometric method of uranium analysis. The results show a good precision and close agreement with those obtained with gamma ray spectroscopy. IAEA uranium leaching analysis has also been applied to this mineral, but only 0,4% of the total content was dissolved. The uranium leaching was more intense on the samples that have smaller equivalent uranium than total uranium and it may be attributed to a higher range Rn gas escape from this mineral. (Author) [pt

Study on geochronology and uranium source of sandstone-type uranium deposit in Dongsheng area

International Nuclear Information System (INIS)

Liu Haibin; Xia Yuliang; Tian Shifeng

2007-01-01

This paper studied the geochronology of sandstone-type uranium deposit in the Dongsheng area of Ordos Basin. In eastern segment, ages of mineralization at the wing of the ore-roll are found to be 120 ± 5 Ma and 80 ± 5 Ma, and at the front of the ore-roll are 20 ± 2 Ma and 8 ± 1 Ma; While in middle segment, ages of mineralization are 124 ± 6 Ma and 80 ± 5 Ma. This means that the main mineralization in Dongsheng area were formed at early Jurassic and late Cretaceous, and correspondent to the time of structure uplift. Mineralization of roll-front (rich ore) which formed in Miocene and Pliocene may related to tectonic-thermal event taken place at that time and reformed the early mineralization in this area. The isochron line age of sample with uranium grade 0 ) in the sandbody is 24.64 x 10 -6 also shows the uranium pre-concentration in the strata. The even value of ΔU of rocks in Zhiluo formation is -70.2%, this shows that non-mineralized rocks have migrated uranium and acted as important metallogenic uranium sources. (authors)

Airborne gamma-ray spectrometer and magnetometer survey, Bend quadrangle (Oregon). Final report

International Nuclear Information System (INIS)

1981-01-01

Eight uranium anomalies meet the minimum statistical requirements as defined in Volume I. These anomalies are listed and are shown on the Uranium Anomaly Interpretation Map. Potassim (%K), equivalent Uranium (ppM eU), equivalent Thorium (ppM eT), eU/eT, eU/K, eT/K, and Magnetic Pseudo Contour Maps are presented in Appendix E. Stacked Profiles showing geologic strip maps along each flight-line, together with sensor data, and ancillary data are presented in Appendix F. All maps and profiles were prepared on a scale of 1:250,000, but have been reduced to 1:500,000 for presentation in Volume II

Re-examining uranium supply and demand: New insights

International Nuclear Information System (INIS)

Kahouli, Sondes

2011-01-01

In this paper, we derive a simultaneous system of equations which aims at analysing the uranium supply and demand. In addition to reviewing and updating previous studies dealing with the uranium market analysis, in particular , the contribution of the paper lies in putting attention to some questions which are still either controversial or unanswered. They are especially related to the controversial hypothesis of the interdependence between uranium market and other commodities markets, both, with respect to the demand side, i.e. oil and coal markets, and the supply side, i.e. gold market. The paper also casts lights on electricity and uranium price effects on uranium demand as well as on the simultaneous interdependencies that may exist between nuclear consumption and nuclear installed capacity. The model is estimated for three different time periods which takes into account the major events that have influenced the nuclear-uranium development, that is, that have constrained the growth rate of nuclear generating capacity, i.e. oil crisis and nuclear accidents. This permits to show if uranium market reaction is independent or it is correlated with specific events associated with each time periods. The model was estimated by using the 3SLS method that correct for the presence of contemporaneously error terms correlation and for the existence of simultaneity bias in the model. Main results give evidence of significant correlation between uranium price and competing fossil fuel prices. They also point-out that uranium price is significantly correlated with the supply forces where supply is significantly dependent on gold prices. Moreover, results show that the electricity prices have a significant effect on the uranium demand only in the post-1990 period, probably following the worldwide electricity prices increasing trend. Further, our estimations show that uranium demand is significantly correlated with uranium price only in the period of nuclear major expansion. As

Re-examining uranium supply and demand: New insights

Energy Technology Data Exchange (ETDEWEB)

Kahouli, Sondes, E-mail: sondes.kahouli@univ-nantes.f [Universite de Nantes, Laboratoire d' Economie et de Management de Nantes Atlantique (LEMNA), Institut d' Economie et de Management de Nantes-I.A.E., Chemin de la Censive du Tertre-B.P. 52231, 44322 Nantes Cedex 3 (France)

2011-01-15

In this paper, we derive a simultaneous system of equations which aims at analysing the uranium supply and demand. In addition to reviewing and updating previous studies dealing with the uranium market analysis, in particular , the contribution of the paper lies in putting attention to some questions which are still either controversial or unanswered. They are especially related to the controversial hypothesis of the interdependence between uranium market and other commodities markets, both, with respect to the demand side, i.e. oil and coal markets, and the supply side, i.e. gold market. The paper also casts lights on electricity and uranium price effects on uranium demand as well as on the simultaneous interdependencies that may exist between nuclear consumption and nuclear installed capacity. The model is estimated for three different time periods which takes into account the major events that have influenced the nuclear-uranium development, that is, that have constrained the growth rate of nuclear generating capacity, i.e. oil crisis and nuclear accidents. This permits to show if uranium market reaction is independent or it is correlated with specific events associated with each time periods. The model was estimated by using the 3SLS method that correct for the presence of contemporaneously error terms correlation and for the existence of simultaneity bias in the model. Main results give evidence of significant correlation between uranium price and competing fossil fuel prices. They also point-out that uranium price is significantly correlated with the supply forces where supply is significantly dependent on gold prices. Moreover, results show that the electricity prices have a significant effect on the uranium demand only in the post-1990 period, probably following the worldwide electricity prices increasing trend. Further, our estimations show that uranium demand is significantly correlated with uranium price only in the period of nuclear major expansion. As

Re-examining uranium supply and demand. New insights

Energy Technology Data Exchange (ETDEWEB)

Kahouli, Sondes [Universite de Nantes, Laboratoire d' Economie et de Management de Nantes Atlantique (LEMNA), Institut d' Economie et de Management de Nantes - I.A.E., Chemin de la Censive du Tertre - B.P. 52231, 44322 Nantes Cedex 3 (France)

2011-01-15

In this paper, we derive a simultaneous system of equations which aims at analysing the uranium supply and demand. In addition to reviewing and updating previous studies dealing with the uranium market analysis, in particular, the contribution of the paper lies in putting attention to some questions which are still either controversial or unanswered. They are especially related to the controversial hypothesis of the interdependence between uranium market and other commodities markets, both, with respect to the demand side, i.e. oil and coal markets, and the supply side, i.e. gold market. The paper also casts lights on electricity and uranium price effects on uranium demand as well as on the simultaneous interdependencies that may exist between nuclear consumption and nuclear installed capacity. The model is estimated for three different time periods which takes into account the major events that have influenced the nuclear-uranium development, that is, that have constrained the growth rate of nuclear generating capacity, i.e. oil crisis and nuclear accidents. This permits to show if uranium market reaction is independent or it is correlated with specific events associated with each time periods. The model was estimated by using the 3SLS method that correct for the presence of contemporaneously error terms correlation and for the existence of simultaneity bias in the model. Main results give evidence of significant correlation between uranium price and competing fossil fuel prices. They also point-out that uranium price is significantly correlated with the supply forces where supply is significantly dependent on gold prices. Moreover, results show that the electricity prices have a significant effect on the uranium demand only in the post-1990 period, probably following the worldwide electricity prices increasing trend. Further, our estimations show that uranium demand is significantly correlated with uranium price only in the period of nuclear major expansion. As

Uranium occurences in the Gorotire Formation quartzites, state of Para, Brazil

International Nuclear Information System (INIS)

Santos, L.C.S. dos

1984-01-01

Seventeen anomalies aligned in a NW/SE structural direction coinciding with teh so called 'Serra do Matao, Southeast Para', were selected for ground-check purposes through the analysis and interpretation of the 'Projeto Geofisico Brasil-Canada' (Brazil-Canada Geophysical Project) results. The mineralized rock is an orthoquartzite with more than 95% silica, fine grained and extremely silicified, with sulphides (pyrite and galena). Uranium is present as fine uraninite crystals associated with the sulphides. It occurs in a disseminated fashion or in small veinlets protected form leaching by late silicification. The uranium appears to be syngenetic in origin being remobilized and reprecipitated as uraninite in veinlets. Values up to 5.800 ppm U 3 O 8 were detected with low values of thorium (usually less than 30 ppm). So far, within the studied areas, no promising targets have been found deserving further investments and investigations. (Author) [pt

Heap leaching procedure for the Uranium extraction

International Nuclear Information System (INIS)

Shishahbore, M. R.

2002-01-01

Heap leaching of Uranium ores is currently in use in several countries. Before taking any decision for construction of heap in industrial scale, it is necessary to obtain the main factors that influence the heap leaching process, such as acid construction, acid solution flowrate, temperature of reaction, or size, ration of liquid to solid, permeability and suitable oxidant. To achieve the above parameters, small scale column leaching is usually recommended. In this project column leaching were carried out in 6 plexiglass column with 43.5 cm an height and 7.4 cm inner diameter. In each column closely 2.00 kg Uranium ore were leached by sulfuric acid. Leaching operation on Iranian ores from two different anomalies from the same area were investigated. In this project, six column were leached at different flowrate of eluent and effect of oxidant were investigated. Acid consumption were in the range of 60 - 144 kg per ton ore and recovery between 73.07% - 99.97%. Finally according to the results obtained, investigated that over are suitable to heap leaching technique. Al tough, to enforce of heap leaching project need to more experiments

Winter to winter recurrence of atmospheric circulation anomalies over East Asia and its impact on winter surface air temperature anomalies.

Science.gov (United States)

Zhao, Xia; Yang, Guang

2017-01-01

The persistence of atmospheric circulation anomalies over East Asia shows a winter to winter recurrence (WTWR) phenomenon. Seasonal variations in sea level pressure anomalies and surface wind anomalies display significantly different characteristics between WTWR and non-WTWR years. The WTWR years are characterized by the recurrence of both a strong (weak) anomalous Siberian High and an East Asian winter monsoon over two successive winters without persistence through the intervening summer. However, anomalies during the non-WTWR years have the opposite sign between the current and ensuing winters. The WTWR of circulation anomalies contributes to that of surface air temperature anomalies (SATAs), which is useful information for improving seasonal and interannual climate predictions over East Asia and China. In the positive (negative) WTWR years, SATAs are cooler (warmer) over East Asia in two successive winters, but the signs of the SATAs are opposite in the preceding and subsequent winters during the non-WTWR years.

Continued Multicolumns Bioleaching for Low Grade Uranium Ore at a Certain Uranium Deposit

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Gongxin Chen

2016-01-01

Full Text Available Bioleaching has lots of advantages compared with traditional heap leaching. In industry, bioleaching of uranium is still facing many problems such as site space, high cost of production, and limited industrial facilities. In this paper, a continued column bioleaching system has been established for leaching a certain uranium ore which contains high fluoride. The analysis of chemical composition of ore shows that the grade of uranium is 0.208%, which is lower than that of other deposits. However, the fluoride content (1.8% of weight is greater than that of other deposits. This can be toxic for bacteria growth in bioleaching progress. In our continued multicolumns bioleaching experiment, the uranium recovery (89.5% of 4th column is greater than those of other columns in 120 days, as well as the acid consumption (33.6 g/kg. These results indicate that continued multicolumns bioleaching technology is suitable for leaching this type of ore. The uranium concentration of PLS can be effectively improved, where uranium recovery can be enhanced by the iron exchange system. Furthermore, this continued multicolumns bioleaching system can effectively utilize the remaining acid of PLS, which can reduce the sulfuric acid consumption. The cost of production of uranium can be reduced and this benefits the environment too.

Method for preparation of uranium hydride

International Nuclear Information System (INIS)

Gorski, M.S.; Goncalves, Miriam; Mirage, A.; Lima, W. de.

1985-01-01

A method for preparation of Uranium Hydride starting from Hidrogen and Uranium is described. In the temperature range of 250 0 up to 350 0 C, and pressures above 10torr, Hydrogen reacts smoothly with Uranium turnings forming a fine black or dark gray powder (UH 3 ). Samples containing a significant amount of oxides show a delay before the reaction begging. (Author) [pt

Uranium abundance in some sudanese phosphate ores

International Nuclear Information System (INIS)

Adam, A.A.; Eltayeb, M.A.H.

2009-01-01

This work was carried out mainly to analysis of some Sudanese phosphate ores, for their uranium abundance and total phosphorus content measured as P 2 O 5 %. For this purpose, 30 samples of two types of phosphate ore from Eastern Nuba Mountains, in Sudan namely, Kurun and Uro areas were examined. In addition, the relationship between uranium and major, and trace elements were obtained, also, the natural radioactivity of the phosphate samples was measured, in order to characterize and differentiate between the two types of phosphate ores. The uranium abundance in Uro phosphate with 20.3% P 2 O 5 is five time higher than in Kurun phosphate with 26.7% P 2 O 5 . The average of uranium content was found to be 56.6 and 310 mg/kg for Kurun and Uro phosphate ore, respectively. The main elements in Kurun and Uro phosphate ore are silicon, aluminum, and phosphorus, while the most abundant trace elements in these two ores are titanium, strontium and barium. Pearson correlation coefficient revealed that uranium in Kurun phosphate shows strong positive correlation with P 2 O 5 , and its distribution is essentially controlled by the variations of P2O5 concentration, whereas uranium in Uro phosphate shows strong positive correlation with strontium, and its distribution is controlled by the variations of Sr concentration. Uranium behaves in different ways in Kurun phosphate and in Uro phosphate. Uro phosphate shows higher concentrations of all the estimated radionuclides than Kurun phosphate. According to the obtained results, it can be concluded that Uro phosphate is consider as secondary uranium source, and is more suitable for uranium recovery, because it has high uranium abundance and low P 2 O 5 %, than Kurun phosphate. (authors) [es

FOETAL ULTRASOUND - NEUROECTODERMAL ANOMALIES IN RURAL PREGNANT WOMEN

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Mala Venkata

2016-06-01

Full Text Available BACKGROUND A prospective clinical study to know the various types of congenital Neuroectodermal Anomalies on obstetric Ultrasound, in rural pregnant women. To reduce the maternal morbidity and mortality by early detection of these Congenital Neuroectodermal Anomalies. To calculate the incidence and prevalence of different types of Congenital Neuroectodermal Anomalies, in these rural pregnant women. To assist the obstetrician in taking decisions regarding the termination or continuation of the pregnancy in relation to the type of malformation and its prognosis. METHODS A prospective clinical study of Congenital Neuroectodermal Anomalies in 22,000 rural pregnant women coming to the Santhiram Medical College, Radiology Department for a routine obstetric scan. 44 cases of neuroectodermal anomalies were detected out of the 22000 cases, within an incidence of 2 per 1000 cases. Approximately 1 in every 500 cases showed an anomaly. RESULTS The most common lesions detected were hydrocephalus, and spina bifida followed by anencephaly. Association of these lesions with consanguinity, previous history of similar anomaly and intake of iron and folic acid tablets was noted. CONCLUSION Ultrasound is an excellent modality for the diagnosis and characterisation of the neuroectodermal anomalies. Its multiplanar imaging property along with real time image visualisation make it an excellent tool for the diagnosis and characterisation of these anomalies

International Uranium Resources Evaluation Project (IUREP) national favourability studies: Indonesia

International Nuclear Information System (INIS)

1977-10-01

Indonesia is a country of south east Asia comprising a large island group extending east-west for over 3000 miles. The geology of Indonesia is fairly well known but is extremely complicated. Successive mountain movements took place around an ancient crustal area. The oldest, of Permian-Triassic age formed northeast Sumatra, northern Java and western Kalimantan. This was followed by the Sumatra orogenesis and finally in Cretaceous and Tertiary times the southern half of Java and the islands as far as New Guinea were formed. Geological studies tend to indicate that the most favourable uranium areas are likely to be in West Sumatra and West Kalimantan. Exploration by the Directorate of Survey and Geology of the National Atomic Energy Agency has been carried out on a small scale since 1961. Exploration concession have been granted to French, German and Japanese organisations. No uranium reserve or resource figures have ever been stated but small occurrences and radioactive anomalies have been found in West and South Sumatra, West and Central Kalimantan and in West Irian. Although the geology of some areas appears to be favourable, little success has attended exploration efforts to date and thus the Speculative Potential is noted as between 1,000 and 10,000 tonnes uranium. (author)

Gamma-Dose rate above uranium mineralization areas in western sudan

International Nuclear Information System (INIS)

Sam, A.K; Sirelkhatim, D.A; Hassona, R.K.

2003-01-01

Absorbed dose rate received from natural external irradiation in uranium mineralisation areas at Uro, Kurun and Jebel Mun was evaluated from the measured activity concentrations of 238 U, 232 Th and 40 K in rock samples.The analyses were performed using alpha-spectrometry and high-resolution gamma-ray spectrometry. A great spatial variability was observed in activity concentration of the primordial radionuclides indicating complexity in geological features. Converses to Jebel Mun, Uro and Kurun deposits exhibit very high U:Th mass ratio. The resulting absorbed dose rate in air as estimated using DRCF's fall within the range of 70-522 (Mun), 569-349 (Uro) and 84-320 n Gy/h (Kurun). At maximum, they correspond to annual effective dose of 0.64, 7.78 and 0.39 mSv, respectively. Uranium is the principal producer of the surface radioactivity at Uro and Kurun as it contributes 99.6% and 95% of the total absorbed dose whereas, in Jebel Mun the cause of radioactive anomaly is due to 40 K and 232 Th. In Uro and Kurun deposits, daughter/parent activity ratios along uranium series, Viz. 234 U: 238 U, 230 Th:U, 210 Po:U, are not differ from the equilibrium value of unity.(Author)

Recovery of uranium from crude uranium tetrafluoride

Energy Technology Data Exchange (ETDEWEB)

Ghosh, S K; Bellary, M P; Keni, V S [Chemical Engineering Division, Bhabha Atomic Research Centre, Mumbai (India)

1994-06-01

An innovative process has been developed for recovery of uranium from crude uranium tetrafluoride cake. The process is based on direct dissolution of uranium tetrafluoride in nitric acid in presence of aluminium hydroxide and use of solvent extraction for removal of fluorides and other bulk impurities to make uranium amenable for refining. It is a simple process requiring minimum process step and has advantage of lesser plant corrosion. This process can be applied for processing of uranium tetrafluoride generated from various sources like uranium by-product during thorium recovery from thorium concentrate, first stage product of uranium recovery from phosphoric acid by OPPA process and off grade uranium tetrafluoride material. The paper describes the details of the process developed and demonstrated on bench and pilot scale and its subsequent modification arising out of bulky solid waste generation. The modified process uses a lower quantity of aluminium hydroxide by allowing a lower dissolution of uranium per cycle and recycles the undissolved material to the next cycle, maintaining the overall recovery at high level. This innovation has reduced the solid waste generated by a factor of four at the cost of a slightly larger dissolution vessel and its increased corrosion rate. (author). 4 refs., 1 fig., 3 tabs.

Recovery of uranium from crude uranium tetrafluoride

International Nuclear Information System (INIS)

Ghosh, S.K.; Bellary, M.P.; Keni, V.S.

1994-01-01

An innovative process has been developed for recovery of uranium from crude uranium tetrafluoride cake. The process is based on direct dissolution of uranium tetrafluoride in nitric acid in presence of aluminium hydroxide and use of solvent extraction for removal of fluorides and other bulk impurities to make uranium amenable for refining. It is a simple process requiring minimum process step and has advantage of lesser plant corrosion. This process can be applied for processing of uranium tetrafluoride generated from various sources like uranium by-product during thorium recovery from thorium concentrate, first stage product of uranium recovery from phosphoric acid by OPPA process and off grade uranium tetrafluoride material. The paper describes the details of the process developed and demonstrated on bench and pilot scale and its subsequent modification arising out of bulky solid waste generation. The modified process uses a lower quantity of aluminium hydroxide by allowing a lower dissolution of uranium per cycle and recycles the undissolved material to the next cycle, maintaining the overall recovery at high level. This innovation has reduced the solid waste generated by a factor of four at the cost of a slightly larger dissolution vessel and its increased corrosion rate. (author)

Uranium-series disequilibria as a means to study recent migration of uranium in a sandstone-hosted uranium deposit, NW China

International Nuclear Information System (INIS)

Min Maozhong; Peng Xinjian; Wang Jinping; Osmond, J.K.

2005-01-01

Uranium concentration and alpha specific activities of uranium decay series nuclides 234 U, 238 U, 230 Th, 232 Th and 226 Ra were measured for 16 oxidized host sandstone samples, 36 oxic-anoxic (mineralized) sandstone samples and three unaltered primary sandstone samples collected from the Shihongtan deposit. The results show that most of the ores and host sandstones have close to secular equilibrium alpha activity ratios for 234 U/ 238 U, 230 Th/ 238 U, 230 Th/ 234 U and 226 Ra/ 230 Th, indicating that intensive groundwater-rock/ore interaction and uranium migration have not taken place in the deposit during the last 1.0 Ma. However, some of the old uranium ore bodies have locally undergone leaching in the oxidizing environment during the past 300 ka to 1.0 Ma or to the present, and a number of new U ore bodies have grown in the oxic-anoxic transition (mineralized) subzone during the past 1.0 Ma. Locally, uranium leaching has taken place during the past 300 ka to 1.0 Ma, and perhaps is still going on now in some sandstones of the oxidizing subzone. However, uranium accumulation has locally occurred in some sandstones of the oxidizing environment during the past 1 ka to 1.0 Ma, which may be attributed to adsorption of U(VI) by clays contained in oxidized sandstones. A recent accumulation of uranium has locally taken place within the unaltered sandstones of the primary subzone close to the oxic-anoxic transition environment during the past 300 ka to 1.0 Ma. Results from the present study also indicate that uranium-series disequilibrium is an important tool to trace recent migration of uranium occurring in sandstone-hosted U deposits during the past 1.0 Ma and to distinguish the oxidation-reduction boundary

Analysis on Space Environment from the Anomalies of Geosynchronous Satellites

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Jaejin Lee

2009-12-01

Full Text Available While it is well known that space environment can produce spacecraft anomaly, defining space environment effects for each anomalies is difficult. This is caused by the fact that spacecraft anomaly shows various symptoms and reproducing it is impossible. In this study, we try to find the conditions of when spacecraft failures happen more frequently and give satellite operators useful information. Especially, our study focuses on the geosynchronous satellites which cost is high and required high reliability. We used satellite anomaly data given by Satellite News Digest which is internet newspaper providing space industry news. In our analysis, 88 anomaly cases occurred from 1997 to 2008 shows bad corelation with Kp index. Satellite malfunctions were likely to happen in spring and fall and in local time from midnight to dawn. In addition, we found the probability of anomaly increase when high energy electron flux is high. This is more clearly appeared in solar minimum than maximum period.

Exploration for uranium in Argentina: New policies of reactivation

International Nuclear Information System (INIS)

Bianchi, R.E.

2009-01-01

Full text: The policy established by the National Government of Argentina in August 2006 related to resuming the Nuclear activity in the country, lead the CNEA trough the Exploration of Raw Materials Manager (ERMM) to establish working strategies for the next 10 years. These strategies together with the assignment of an adequate budget will contribute to define new uranium resources, which together with the already known ones, will be used to supply the requirements of Nuclear Power and Research Plants in the future. Thus, the ERMM is applying a policy of human resources hiring new personnel in order to count with the minimum necessary workforce to reach these tasks. In Argentina known U resources are related to sedimentary, igneous and metamorphic environments. Considering the geology of the different regions, Argentina has been divided into 57 units in which the geological, geochemical, mineralogical and structural information is evaluated in order to estimate the uranium geological favorability of each unit. The final pursuit of this regional study is to circumscribe new areas with anomalous uranium contents in which prospection and exploration should be carried out. These studies together with prospection and exploration works are performed in the country by four exploration centers based in Salta (RN), Cordoba (R.Ce), Mendoza (R.Cu) and Trelew (RP). The works planned for each exploration center includes: Regional Noroeste, Mina Franca Deposit: peri-granitic vein- type mineralization: 25% of surface exploration has been performed. Mineralized areas: Istataco and San Buenaventura correspond to an igneous-metamorphic environment, Sierra de Vaqueria to a sedimentary one: Prospection stage. Regional Centro, Mineralized areas: El Gallo: drilling stage and Donato: prospection stage, correspond to an igneous-metamorphic environment with intra and peri-granitic anomalies. Noya: prospection stage, sedimentary environment. Regional Cuyo, Mineralized area: Western Sierra

Drawing of uranium in γ phase

International Nuclear Information System (INIS)

Stohr, J.A.

1955-01-01

It describes the study of working and drawing of uranium in γ phase. In a first part, the forgeable characteristics of uranium metal in the three different phases (α, β and γ) are compared by using BASTIEN-PORTEVIN method. The different experiments are testing the behaviour metal in each phase under different stresses and a temperature gradient as slow and shock traction, slow and shock compression, resilience, flexibility. Results show that optimum conditions for uranium drawing is uranium in phase γ. In a second part, it described the drawing method and process. The uranium rods obtained by this technique are of very good quality. In addition, the material wear is very low which permits a low production cost. Finally, the uranium rod physical properties are studied. (M.P.)

Acidic aqueous uranium electrodeposition for target fabrication

International Nuclear Information System (INIS)

Saliba-Silva, A.M.; Oliveira, E.T.; Garcia, R.H.L.; Durazzo, M.

2013-01-01

Direct irradiation of targets inside nuclear research or multiple purpose reactors is a common route to produce 99 Mo- 99m Tc radioisotopes. The electroplating of low enriched uranium over nickel substrate might be a potential alternative to produce targets of 235 U. The electrochemistry of uranium at low temperature might be beneficial for an alternative route to produce 99 Mo irradiation LEU targets. Electrodeposition of uranium can be made using ionic and aqueous solutions producing uranium oxide deposits. The performance of uranium electrodeposition is relatively low because a big competition with H 2 evolution happens inside the window of electrochemical reduction potential. This work explores possibilities of electroplating uranium as UO 2 2+ (Uranium-VI) in order to achieve electroplating uranium in a sufficient amount to be commercially irradiated in the future Brazilian RMB reactor. Electroplated nickel substrate was followed by cathodic current electrodeposition from aqueous UO 2 (NO 3 ) 2 solution. EIS tests and modeling showed that a film formed differently in the three tested cathodic potentials. At the lower level, (-1.8V) there was an indication of a double film formation, one overlaying the other with ionic mass diffusion impaired at the interface with nickel substrate as showed by the relatively lower admittance of Warburg component. (author)

An improved FT-TIMS method of measuring uranium isotope ratios in the uranium-bearing particles

International Nuclear Information System (INIS)

Chen, Yan; Wang, Fan; Zhao, Yong-Gang; Li, Li-Li; Zhang, Yan; Shen, Yan; Chang, Zhi-Yuan; Guo, Shi-Lun; Wang, Xiao-Ming; Cui, Jian-Yong; Liu, Yu-Ang

2015-01-01

An improved method of Fission Track technique combined with Thermal Ionization Mass Spectrometry (FT-TIMS) was established in order to determine isotope ratio of uranium-bearing particle. Working standard of uranium oxide particles with a defined diameter and isotopic composition were prepared and used to review the method. Results showed an excellent agreement with certified values. The developed method was used to analyze isotope ratio of single uranium-bearing particle in swipe samples successfully. The analysis results of uranium-bearing particles in swipe samples accorded with the operation history of the origin. - Highlights: • The developed method was successfully applied in the analysis of real swipe sample. • Uranium-bearing particles were confined in the middle of track detector. • The fission tracks of collodion film and PC film could be confirmed each other. • The thickness of collodion film should be no more than about 60 μm. • The method could avoid losing uranium-bearing particles in the etching step.

Kohn anomalies in superconductors

International Nuclear Information System (INIS)

Flatte, M.E.

1994-01-01

The detailed behavior of phonon dispersion curves near momenta which span the electronic Fermi sea in a superconductor is presented. An anomaly, similar to the metallic Kohn anomaly, exists in a superconductor's dispersion curves when the frequency of the photon spanning the Fermi sea exceeds twice the superconducting energy gap. This anomaly occurs at approximately the same momentum but is stronger than the normal-state Kohn anomaly. It also survives at finite temperature, unlike the metallic anomaly. Determination of Fermi-surface diameters from the location of these anomalies, therefore, may be more successful in the superconducting phase than in the normal state. However, the superconductor's anomaly fades rapidly with increased phonon frequency and becomes unobservable when the phonon frequency greatly exceeds the gap. This constraint makes these anomalies useful only in high-temperature superconductors such as La 1.85 Sr 0.15 CuO 4

Behaviour of uranium during late-Hercynian and alpine metamorphisms in the Aiguilles rouges and Belledonne (Valorcine, Lauziere) massifs. Western Alps

International Nuclear Information System (INIS)

Negga, H.S.

1984-01-01

The purpose of this research thesis is to define the origin of numerous uranium anomalies in the external crystalline Alpine massifs, more precisely the massif of the Aiguilles Rouges and the massif of Belledonne. The primary cause of uranium mineralization in the first massif appears to have been the retrograde metamorphism events of the late-Hercynian age. In the second massif, the same conditions of uranium mineralization appear to have been realised, but with a much higher calcium activity in the fluids. After having explained the choice of the selected areas, the sampling and the chemical analysis performed, the author describes the geological and structural framework of Western Alps: geological history of the paleozoic platform, regional geology of the studied massifs. The next part reports the petrographic and geochemical study, the analysis of the mineral chemistry, of the alteration and the metamorphism. Then the author describes the geochemistry of uranium and thorium within the studied structures

Potentiometric determination of hexavalent uranium in uranium silicide samples

International Nuclear Information System (INIS)

Arlegui, Oscar

1999-01-01

The Chilean Nuclear Energy Commission's Department of Nuclear Materials has among its projects the production of fuels elements for nuclear reactors, and, therefore, the Chemical Analysis Laboratory must have a rapid and reliable method for uranium analysis, to control the uranium concentration during each stage of the production process. For this reason the Chilean Nuclear Energy Commission's Chemical Analysis Laboratory has validated a potentiometric method, which is a modification of the Davies and Gray method proposed by A.R. Eberle. This method uses the Potentiometric Titration Technique and is based on the direct and rapid reduction of uranium (VI) to Uranium (IV), in a concentrated phosphoric acid medium, with excess iron (II) used as a reducing agent. In this medium the excess iron (II) selectively oxidizes to iron (III) with nitric acid, using molybdenum (IV) as a catalyzer, the nitrous acid that is produced is eliminated by adding amidosulfuric acid. The solution is diluted with 1M sulfuric acid and the uranium (IV) obtained is titrated potentiometrically with potassium dichromate in the presence of vanadilic sulfate to obtain a better defined final titration point. The samples were softened with hydrochloric acid and nitric acid and later 50 ml were estimated in a 20% sulfuric acid medium. The analytical method was validated by comparing it with Certified Reference Material (C.R.M.) from the New Brunswick Laboratory (NBL), Metallic Uranium, CRM 112-A. The F Test and the T Test show that the value calculated is less than the tabulated value so the result is traceable to the reference material. The quantification limit, sensitivity, precision and accuracy were quantified for the method

Analysis of renal anomalies in VACTERL association.

Science.gov (United States)

Cunningham, Bridget K; Khromykh, Alina; Martinez, Ariel F; Carney, Tyler; Hadley, Donald W; Solomon, Benjamin D

2014-10-01

VACTERL association refers to a combination of congenital anomalies that can include: vertebral anomalies, anal atresia, cardiac malformations, tracheo-esophageal fistula with esophageal atresia, renal anomalies (typically structural renal anomalies), and limb anomalies. We conducted a description of a case series to characterize renal findings in a cohort of patients with VACTERL association. Out of the overall cohort, 48 patients (with at least three component features of VACTERL and who had abdominal ultrasound performed) met criteria for analysis. Four other patients were additionally analyzed separately, with the hypothesis that subtle renal system anomalies may occur in patients who would not otherwise meet criteria for VACTERL association. Thirty-three (69%) of the 48 patients had a clinical manifestation affecting the renal system. The most common renal manifestation (RM) was vesicoureteral reflux (VUR) in addition to a structural defect (present in 27%), followed by unilateral renal agenesis (24%), and then dysplastic/multicystic kidneys or duplicated collected system (18% for each). Twenty-two (88%) of the 25 patients with a structural RM had an associated anorectal malformation. Individuals with either isolated lower anatomic anomalies, or both upper and lower anatomic anomalies were not statistically more likely to have a structural renal defect than those with isolated upper anatomic anomalies (p = 0.22, p = 0.284, respectively). Given the high prevalence of isolated VUR in our cohort, we recommend a screening VCUG or other imaging modality be obtained to evaluate for VUR if initial renal ultrasound shows evidence of obstruction or renal scarring, as well as ongoing evaluation of renal health. © 2014 Wiley Periodicals, Inc.

Analytical method of uranium (IV) and uranium (VI) in uranium ores and uranium-bearing rocks

International Nuclear Information System (INIS)

Shen Zhuqin; Zheng Yongfeng; Li Qingzhen; Zhong Miaolan; Gu Dingxiang

1995-11-01

The best conditions for keeping the original valences of uranium during the dissolution and separation procedure of geological samples (especially those micro uranium-bearing rock) were studied. With the exist of high concentration protectants, the sample was decomposed with concentration HF at 40 +- 5 degree C. The U(VI) was dissolved completely and formed stable complex UO 2 F 2 , the U(IV) was precipitated rapidly and carried by carrier. Quantitative separation was carried out immediately with suction. The decomposition of sample and separation of solid/liquid phases was completed within two minutes. After separation, the U(IV) and U(VI) were determined quantitatively with laser fluorescence or voltametry respectively according to the uranium content. The limit of detection for this method is 0.7 μg/g, RSD is 10.5%, the determinate range of uranium is 2 x 10 -6 ∼10 -1 g/g. The uranium contents and their valence state ratio were measured for more than one hundred samples of sand stone and granite, the accuracy and precision of these results are satisfactory for uranium geological research. (12 tabs.; 11 refs.)

Reduction of uranium hexafluoride to uranium tetrafluoride

International Nuclear Information System (INIS)

Chang, I.S.; Do, J.B.; Choi, Y.D.; Park, M.H.; Yun, H.H.; Kim, E.H.; Kim, Y.W.

1982-01-01

The single step continuous reduction of uranium hexafluoride (UF 6 ) to uranium tetrafluoride (UF 4 ) has been investigated. Heat required to initiate and maintain the reaction in the reactor is supplied by the highly exothermic reaction of hydrogen with a small amount of elemental fluorine which is added to the uranium hexafluoride stream. When gases uranium hexafluoride and hydrogen react in a vertical monel pipe reactor, the green product, UF 4 has 2.5g/cc in bulk density and is partly contaminated by incomplete reduction products (UF 5 ,U 2 F 9 ) and the corrosion product, presumably, of monel pipe of the reactor itself, but its assay (93% of UF 4 ) is acceptable for the preparation of uranium metal with magnesium metal. Remaining problems are the handling of uranium hexafluoride, which is easily clogging the flowmeter and gas feeding lines because of extreme sensitivity toward moisture, and a development of gas nozzel for free flow of uranium hexafluoride gas. (Author)

Uranium uptake and accumulation in plants from soil contaminated with uranium in different concentrations

International Nuclear Information System (INIS)

Zhao Luxue; Tang Yongjin; Luo Xuegang

2014-01-01

The plants of Medicago sativa L., Hibiscus esulentus L, Waterspinach, Amaranthus retroflexus and Abutilon theophrasti Medic were employed as the indicator to investigate the uranium uptake and accumulation from soils contaminated with uranium (UO_2 (CH_3COO)_2 · 2H_2O) of 25 mg · kg"-"l, 75 mg · kg"-"1, 125 mg · kg"-"l, 175 mg · kg"-"l respectively, in a pot experiment. The result shows that, U concentration in the aerial part and underground part of the whole plant increased with the rise of uranium concentration in the soils. In the contaminated soils with 25∼125 mg · kg"-"l concentrations of uranium, U content of Medicago sativa L is the highset (6.78 mg · kg"-"l, 61.53 mg · kg"-"l, 74.06 mg · kg"-"l separately). While in the 175 mg · kg"-"l concentration of uranium contaminated soils, U content of Hibiscus esulentus L is the highest (86.72 mg · kg"-"1), which is mainly because of U concentration in its roots have higher level of uranium (388.16 mg · kg"-"l). Comprehensive analysis shows that Medicago sativa L. is a good plant for phytoextraction and Hibiscus esulentus L is a good immobilizing plant for phytoremediation. The results can provide some theoretical basis and technical support for remedying U-contaminated soils in different areas of our country. (authors)

Precise coulometric titration of uranium in a high-purity uranium metal and in uranium compounds

International Nuclear Information System (INIS)

Tanaka, Tatsuhiko; Yoshimori, Takayoshi

1975-01-01

Uranium in uranyl nitrate, uranium trioxide and a high-purity uranium metal was assayed by the coulometric titration with biamperometric end-point detection. Uranium (VI) was reduced to uranium (IV) by solid bismuth amalgam in 5M sulfuric acid solution. The reduced uranium was reoxidized to uranium (VI) with a large excess of ferric ion at a room temperature, and the ferrous ion produced was titrated with the electrogenerated manganese(III) fluoride. In the analyses of uranium nitrate and uranium trioxide, the results were precise enough when the error from uncertainty in water content in the samples was considered. The standard sample of pure uranium metal (JAERI-U4) was assayed by the proposed method. The sample was cut into small chips of about 0.2g. Oxides on the metal surface were removed by the procedure shown by National Bureau of Standards just before weighing. The mean assay value of eleven determinations corrected for 3ppm of iron was (99.998+-0.012) % (the 95% confidence interval for the mean), with a standard deviation of 0.018%. The proposed coulometric method is simple and permits accurate and precise determination of uranium which is matrix constituent in a sample. (auth.)

31 CFR 540.317 - Uranium feed; natural uranium feed.

Science.gov (United States)

2010-07-01

... 31 Money and Finance: Treasury 3 2010-07-01 2010-07-01 false Uranium feed; natural uranium feed... (Continued) OFFICE OF FOREIGN ASSETS CONTROL, DEPARTMENT OF THE TREASURY HIGHLY ENRICHED URANIUM (HEU) AGREEMENT ASSETS CONTROL REGULATIONS General Definitions § 540.317 Uranium feed; natural uranium feed. The...

Uranium exploration

International Nuclear Information System (INIS)

De Voto, R.H.

1984-01-01

This paper is a review of the methodology and technology that are currently being used in varying degrees in uranium exploration activities worldwide. Since uranium is ubiquitous and occurs in trace amounts (0.2 to 5 ppm) in virtually all rocks of the crust of the earth, exploration for uranium is essentially the search of geologic environments in which geologic processes have produced unusual concentrations of uranium. Since the level of concentration of uranium of economic interest is dependent on the present and future price of uranium, it is appropriate here to review briefly the economic realities of uranium-fueled power generation. (author)

Uranium

International Nuclear Information System (INIS)

1982-01-01

The development, prospecting, research, processing and marketing of South Africa's uranium industry and the national policies surrounding this industry form the headlines of this work. The geology of South Africa's uranium occurences and their positions, the processes used in the extraction of South Africa's uranium and the utilisation of uranium for power production as represented by the Koeberg nuclear power station near Cape Town are included in this publication

Uranium removal from soils: An overview from the Uranium in Soils Integrated Demonstration program

International Nuclear Information System (INIS)

Francis, C.W.; Brainard, J.R.; York, D.A.; Chaiko, D.J.; Matthern, G.

1994-01-01

An integrated approach to remove uranium from uranium-contaminated soils is being conducted by four of the US Department of Energy national laboratories. In this approach, managed through the Uranium in Soils Integrated Demonstration program at the Fernald Environmental Management Project, Fernald, Ohio, these laboratories are developing processes that selectively remove uranium from soil without seriously degrading the soil's physicochemical characteristics or generating waste that is difficult to manage or dispose of. These processes include traditional uranium extractions that use carbonate as well as some nontraditional extraction techniques that use citric acid and complex organic chelating agents such as naturally occurring microbial siderophores. A bench-scale engineering design for heap leaching; a process that uses carbonate leaching media shows that >90% of the uranium can be removed from the Fernald soils. Other work involves amending soils with cultures of sulfur and ferrous oxidizing microbes or cultures of fungi whose role is to generate mycorrhiza that excrete strong complexers for uranium. Aqueous biphasic extraction, a physical separation technology, is also being evaluated because of its ability to segregate fine particulate, a fundamental requirement for soils containing high levels of silt and clay. Interactions among participating scientists have produced some significant progress not only in evaluating the feasibility of uranium removal but also in understanding some important technical aspects of the task

Airborne gamma-ray spectrometer and magnetometer survey, Salem quadrangle (Oregon). Final report

International Nuclear Information System (INIS)

1981-01-01

Five uranium anomalies meet the minimum statistical requirements as defined in Volume I. These anomalies are tabulated and are shown on the Uranium Anomaly Interpretation Map. Potassium (%K), equivalent Uranium (ppM eU), equivalent Thorium (eT), eU/eT, eU/K, eT/K, and magnetic pseudo-contour maps are presented in Appendix E. Stacked Profiles showing geologic strip maps along each flight-line, together with sensor data, and ancillary data are presented in Appendix F. All maps and profiles were prepared on a scale of 1:250,000, but have been reduced to 1:500,000 for presentation in Volume II. Each of the anomalies occurs over the Eocene Tyee and Burpee formation (Teme), a rhythmically banded, feldspathic and micaceous, massive bedded sandstone, and siltstone. Anomalies 1, 2, 3, and 4 are in the northwest corner of the map. Anomalies 2 and 3 are near faults, so may be due to radon leaking from the faults. Anomaly No. 5 is in the southwest corner of the map

Controlled Source Audio Magneto Telluric (CSAMT) studies for uranium exploration in Durgi area, Palnad sub-basin, Cuddapah basin, India

International Nuclear Information System (INIS)

Kumar, Indresh; Kumar, S. Vijaya; Ramesh Babu, V.; Kumar, B.V.L.; Dash, J.K.; Chaturvedi, A.K.

2017-01-01

Cuddapah basin is known for hosting unconformity proximal uranium deposits viz., Lambapur, Peddagattu, Chitirial and Koppunuru along the northern margin of the basin. It is well known that these deposits are mostly associated with basement granitoids in Srisailam Sub-basin, and with cover sediments in Palnad subbasin where basement topography and fault/fracture system influence the fluid flow causing basement alteration and ore deposition. Geological setup, surface manifestation of uranium anomalies and association of the hydro-uranium anomalies near Durgi area in southern part of the Palnad sub-basin, have prompted detail investigation by geophysical methods to probe greater depths. Controlled Source Audio Magneto Telluric (CSAMT) survey conducted over five decades of frequency (0.1-9600 Hz) delineated the various lithounits of Kurnool and Nallamalai Groups along with their thicknesses as there exist an appreciable resistivity contrast. Interpretation of CSAMT sounding data are constrained by resistivity logs and litholog data obtained from the boreholes drilled within the basin indicated three to four layered structure. Sub-surface 2-D and 3-D geo-electrical models are simulated by stitching 1-D layered inverted resistivity earth models. Stitched 1-D inverted resistivity sections revealed the unconformity between the Kurnool Group and Nallamalai Group along with basement undulations. The faults/fractures delineated from the CSAMT data corroborated well with the results of gravity data acquired over the same area. Simulated 3-D voxel resistivity model helped in visualising the faults/fractures, their depth extent, thickness of the Banganapalle quartzite and basement configuration. Integrated interpretation of CSAMT, gravity and borehole data facilitated in delineating the unconformity and the structural features favourable for uranium mineralisation in deeper parts of the Palnad sub-basin. (author)

Influence of uranium hydride oxidation on uranium metal behaviour

International Nuclear Information System (INIS)

Patel, N.; Hambley, D.; Clarke, S.A.; Simpson, K.

2013-01-01

This work addresses concerns that the rapid, exothermic oxidation of active uranium hydride in air could stimulate an exothermic reaction (burning) involving any adjacent uranium metal, so as to increase the potential hazard arising from a hydride reaction. The effect of the thermal reaction of active uranium hydride, especially in contact with uranium metal, does not increase in proportion with hydride mass, particularly when considering large quantities of hydride. Whether uranium metal continues to burn in the long term is a function of the uranium metal and its surroundings. The source of the initial heat input to the uranium, if sufficient to cause ignition, is not important. Sustained burning of uranium requires the rate of heat generation to be sufficient to offset the total rate of heat loss so as to maintain an elevated temperature. For dense uranium, this is very difficult to achieve in naturally occurring circumstances. Areas of the uranium surface can lose heat but not generate heat. Heat can be lost by conduction, through contact with other materials, and by convection and radiation, e.g. from areas where the uranium surface is covered with a layer of oxidised material, such as burned-out hydride or from fuel cladding. These rates of heat loss are highly significant in relation to the rate of heat generation by sustained oxidation of uranium in air. Finite volume modelling has been used to examine the behaviour of a magnesium-clad uranium metal fuel element within a bottle surrounded by other un-bottled fuel elements. In the event that the bottle is breached, suddenly, in air, it can be concluded that the bulk uranium metal oxidation reaction will not reach a self-sustaining level and the mass of uranium oxidised will likely to be small in relation to mass of uranium hydride oxidised. (authors)

Influence of uranium hydride oxidation on uranium metal behaviour

Energy Technology Data Exchange (ETDEWEB)

Patel, N.; Hambley, D. [National Nuclear Laboratory (United Kingdom); Clarke, S.A. [Sellafield Ltd (United Kingdom); Simpson, K.

2013-07-01

This work addresses concerns that the rapid, exothermic oxidation of active uranium hydride in air could stimulate an exothermic reaction (burning) involving any adjacent uranium metal, so as to increase the potential hazard arising from a hydride reaction. The effect of the thermal reaction of active uranium hydride, especially in contact with uranium metal, does not increase in proportion with hydride mass, particularly when considering large quantities of hydride. Whether uranium metal continues to burn in the long term is a function of the uranium metal and its surroundings. The source of the initial heat input to the uranium, if sufficient to cause ignition, is not important. Sustained burning of uranium requires the rate of heat generation to be sufficient to offset the total rate of heat loss so as to maintain an elevated temperature. For dense uranium, this is very difficult to achieve in naturally occurring circumstances. Areas of the uranium surface can lose heat but not generate heat. Heat can be lost by conduction, through contact with other materials, and by convection and radiation, e.g. from areas where the uranium surface is covered with a layer of oxidised material, such as burned-out hydride or from fuel cladding. These rates of heat loss are highly significant in relation to the rate of heat generation by sustained oxidation of uranium in air. Finite volume modelling has been used to examine the behaviour of a magnesium-clad uranium metal fuel element within a bottle surrounded by other un-bottled fuel elements. In the event that the bottle is breached, suddenly, in air, it can be concluded that the bulk uranium metal oxidation reaction will not reach a self-sustaining level and the mass of uranium oxidised will likely to be small in relation to mass of uranium hydride oxidised. (authors)

Nonrelativistic trace and diffeomorphism anomalies in particle number background

Science.gov (United States)

Auzzi, Roberto; Baiguera, Stefano; Nardelli, Giuseppe

2018-04-01

Using the heat kernel method, we compute nonrelativistic trace anomalies for Schrödinger theories in flat spacetime, with a generic background gauge field for the particle number symmetry, both for a free scalar and a free fermion. The result is genuinely nonrelativistic, and it has no counterpart in the relativistic case. Contrary to naive expectations, the anomaly is not gauge invariant; this is similar to the nongauge covariance of the non-Abelian relativistic anomaly. We also show that, in the same background, the gravitational anomaly for a nonrelativistic scalar vanishes.

Uranium concentrations in fossils measured by SIMS

International Nuclear Information System (INIS)

Uyeda, Chiaki; Okano, Jun

1988-01-01

Semiquantitative analyses of uranium in fossil bones and teeth were carried out by SIMS. The results show a tendency that uranium concentrations in the fossils increase with the ages of the fossils. It is noticed that fossil bones and teeth having uranium concentration of more than several hundred ppm are not rare. (author)

Uranium conversion; Urankonvertering

Energy Technology Data Exchange (ETDEWEB)

Oliver, Lena; Peterson, Jenny; Wilhelmsen, Katarina [Swedish Defence Research Agency (FOI), Stockholm (Sweden)

2006-03-15

FOI, has performed a study on uranium conversion processes that are of importance in the production of different uranium compounds in the nuclear industry. The same conversion processes are of interest both when production of nuclear fuel and production of fissile material for nuclear weapons are considered. Countries that have nuclear weapons ambitions, with the intention to produce highly enriched uranium for weapons purposes, need some degree of uranium conversion capability depending on the uranium feed material available. This report describes the processes that are needed from uranium mining and milling to the different conversion processes for converting uranium ore concentrate to uranium hexafluoride. Uranium hexafluoride is the uranium compound used in most enrichment facilities. The processes needed to produce uranium dioxide for use in nuclear fuel and the processes needed to convert different uranium compounds to uranium metal - the form of uranium that is used in a nuclear weapon - are also presented. The production of uranium ore concentrate from uranium ore is included since uranium ore concentrate is the feed material required for a uranium conversion facility. Both the chemistry and principles or the different uranium conversion processes and the equipment needed in the processes are described. Since most of the equipment that is used in a uranium conversion facility is similar to that used in conventional chemical industry, it is difficult to determine if certain equipment is considered for uranium conversion or not. However, the chemical conversion processes where UF{sub 6} and UF{sub 4} are present require equipment that is made of corrosion resistant material.

Conformal anomaly actions for dilaton interactions

Directory of Open Access Journals (Sweden)

Rose Luigi Delle

2014-01-01

Full Text Available We discuss, in conformally invariant field theories such as QCD with massless fermions, a possible link between the perturbative signature of the conformal anomaly, in the form of anomaly poles of the 1-particle irreducible effective action, and its descrip- tion in terms of Wess-Zumino actions with a dilaton. The two descriptions are expected to capture the UV and IR behaviour of the conformal anomaly, in terms of fundamental and effective degrees of freedom respectively, with the dilaton effective state appearing in a nonlinear realization. As in the chiral case, conformal anomalies seem to be related to the appearance of these effective interactions in the 1PI action in all the gauge-invariant sectors of the Standard Model. We show that, as a consequence of the underlying anomalous symmetry, the infinite hierarchy of recurrence relations involving self-interactions of the dilaton is entirely determined only by the first four of them. This relation can be generalized to any even space-time dimension.

Introduction to anomalies

International Nuclear Information System (INIS)

Alvarez-Gaume, L.

1986-01-01

These lectures are dedicated to the study of the recent progress and implications of anomalies in quantum field theory. In this introduction the author recapitulates some of the highlights in the history of the subject. The outline of these lectures is as follows: Section II contains a quick review of spinors in Euclidean and Minkowski space, some other group theory results relevant for the computation of anomalies in various dimensions, and an exposition of the index theorem. Section III starts the analysis of fermion determinants and chiral effective actions by deriving the non-Abelian anomaly from index theory. Using the results of Section II, the anomaly cancellation recently discovered by Green and Schwarz will be presented in Section IV as well as the connection of these results of Section III with the descent equations and the Wess-Zumino-Witten Lagrangians. Section V contains the generalization of anomalies to σ-models and some of its application in string theory. Section VI will deal with the anomalies from the Hamiltonian point of view. An exact formula for the imaginary part of the effective action for chiral fermions in the presence of arbitrary external gauge and gravitational fields will be derived in Section VII, and used in Section VIII for the study of global anomalies. 85 references

Inventory of uranium resources potency at Kawat area, upper Mahakam, East Kalimantan detailed prospecting stage

International Nuclear Information System (INIS)

Ngadenin; I Gde Sukadana; Adi Gunawan Muhammad; Suripto

2011-01-01

Result of the general prospecting in East Kalimantan has found several radioactivity outcrop anomalies at upper Mahakam in the acid volcanic rock area which is approximately 25 km 2 in wide. The objective of the research is to know detailed geological information and characteristic of uranium mineralization. Method of this research are detailed geological, radiometric and geochemical mapping 1:10.000 on scale. The lithology of Kawat area is composed of seven units of rock. They are black clay unit, feldspatic sandstone unit, Nyaan rhyolite unit, lower andesite unit, Kawat rhyolite unit, upper andesite unit and tuffaceous sandstone unit. Evolving fault is dextral fault and normal fault. The trending of dextral fault is west-east and southwest-northeast, meanwhile the trending of normal faults is west-east and southwest northeast. There are two period of uranium mineralization occurrences in the area, the first is connected with the eruption of Nyaan rhyolite magma and the second is connected with the eruption of Kawat rhyolite magma. Uranium mineralization occurred in the stage of hydrothermal process and including in the pneumatogenic class of volcanogenic uranium deposits. This investigation has yielded two sites of potential uranium sector are the Nyaan sector with an area of about 6 km 2 and Kawat sector with an area of about 10 km 2 . (author)

Algebraic structure of chiral anomalies

International Nuclear Information System (INIS)

Stora, R.

1985-09-01

I will describe first the algebraic aspects of chiral anomalies, exercising however due care about the topological delicacies. I will illustrate the structure and methods in the context of gauge anomalies and will eventually make contact with results obtained from index theory. I will go into two sorts of generalizations: on the one hand, generalizing the algebraic set up yields e.g. gravitational and mixed gauge anomalies, supersymmetric gauge anomalies, anomalies in supergravity theories; on the other hand most constructions applied to the cohomologies which characterize anomalies easily extend to higher cohomologies. Section II is devoted to a description of the general set up as it applies to gauge anomalies. Section III deals with a number of algebraic set ups which characterize more general types of anomalies: gravitational and mixed gauge anomalies, supersymmetric gauge anomalies, anomalies in supergravity theories. It also includes brief remarks on σ models and a reminder on the full BRST algebra of quantized gauge theories

A Correlation between Renal Anomalies and Vesicoureteral Reflux

International Nuclear Information System (INIS)

Kim, Seung Soo; Kim, Young Tong; Kim, Il Young; Shin, Hyeong Cheol

2011-01-01

To investigate the frequency of vesicoureteral reflux (VUR) in children with renal anomalies a evaluate the correlation between renal anomalies and VUR. Eighty-one children (1 day-8 years) with renal anomalies underwent voiding cystourethrogram between 2006 and 2009 were reviewed. This study included ureteropelvic junction stenosis (n = 32), ureteropelvic duplication (n = 20), multicystic dysplastic kidney (n = 12), fusion anomaly (n = 11), renal agenesis (n = 3), unilateral renal hypoplasia (n = 2), and ectopic kidney (n = 1). The frequency, grade, and location of VUR were evaluated. The grade of VUR according to age and anomaly type was statistically analyzed, and the patients with VUR were followed. The VUR was present in 14 (17.3%); ipsilateral VUR was present in 8 (57.1%), bilateral VUR in 4 (28.6%), and contralateral VUR in 2 (14.2%). VUR was detected in 9 patients under the age of one. There was no statistical correlation between VUR grade and either age or anomaly type of the nine patients showed continuous VUR on up. The frequency of VUR in children with renal anomalies was 17.3%. VUR was most frequently detected in children under the age of one, and VUR grade was not related to age and anomaly type.

A Correlation between Renal Anomalies and Vesicoureteral Reflux

Energy Technology Data Exchange (ETDEWEB)

Kim, Seung Soo; Kim, Young Tong; Kim, Il Young; Shin, Hyeong Cheol [Dept. of Radiology, Cheonan Hospital, Soonchunhyang University College of Medicine, Cheonan (Korea, Republic of)

2011-12-15

To investigate the frequency of vesicoureteral reflux (VUR) in children with renal anomalies a evaluate the correlation between renal anomalies and VUR. Eighty-one children (1 day-8 years) with renal anomalies underwent voiding cystourethrogram between 2006 and 2009 were reviewed. This study included ureteropelvic junction stenosis (n = 32), ureteropelvic duplication (n = 20), multicystic dysplastic kidney (n = 12), fusion anomaly (n = 11), renal agenesis (n = 3), unilateral renal hypoplasia (n = 2), and ectopic kidney (n = 1). The frequency, grade, and location of VUR were evaluated. The grade of VUR according to age and anomaly type was statistically analyzed, and the patients with VUR were followed. The VUR was present in 14 (17.3%); ipsilateral VUR was present in 8 (57.1%), bilateral VUR in 4 (28.6%), and contralateral VUR in 2 (14.2%). VUR was detected in 9 patients under the age of one. There was no statistical correlation between VUR grade and either age or anomaly type of the nine patients showed continuous VUR on up. The frequency of VUR in children with renal anomalies was 17.3%. VUR was most frequently detected in children under the age of one, and VUR grade was not related to age and anomaly type.

Chiral anomalies and differential geometry

International Nuclear Information System (INIS)

Zumino, B.

1983-10-01

Some properties of chiral anomalies are described from a geometric point of view. Topics include chiral anomalies and differential forms, transformation properties of the anomalies, identification and use of the anomalies, and normalization of the anomalies. 22 references

Uranium from seawater

International Nuclear Information System (INIS)

Gregg, D.; Folkendt, M.

1982-01-01

A novel process for recovering uranium from seawater is proposed and some of the critical technical parameters are evaluated. The process, in summary, consists of two different options for contacting adsorbant pellets with seawater without pumping the seawater. It is expected that this will reduce the mass handling requirements, compared to pumped seawater systems, by a factor of approximately 10 5 , which should also result in a large reduction in initial capital investment. Activated carbon, possibly in combination with a small amount of dissolved titanium hydroxide, is expected to be the preferred adsorbant material instead of the commonly assumed titanium hydroxide alone. The activated carbon, after exposure to seawater, can be stripped of uranium with an appropriate eluant (probably an acid) or can be burned for its heating value (possible in a power plant) leaving the uranium further enriched in its ash. The uranium, representing about 1% of the ash, is then a rich ore and would be recovered in a conventional manner. Experimental results have indicated that activated carbon, acting alone, is not adequately effective in adsorbing the uranium from seawater. We measured partition coefficients (concentration ratios) of approximately 10 3 in seawater instead of the reported values of 10 5 . However, preliminary tests carried out in fresh water show considerable promise for an extraction system that uses a combination of dissolved titanium hydroxide (in minute amounts) which forms an insoluble compound with the uranyl ion, and the insoluble compound then being sorbed out on activated carbon. Such a system showed partition coefficients in excess of 10 5 in fresh water. However, the system was not tested in seawater

Developmental anomaly of the hyoid bone: an unusual cause of dysphagia; Anomalie de developpement de l'os hyoide: une cause inhabituelle de dysphagie

Energy Technology Data Exchange (ETDEWEB)

Bayadjian, A.; Marsot-Dupuch, K.; Schmitt, E.; Chouard, Ch.; Tubiana, J.M. [Hopital Saint Antoine, 75 - Paris (France)

2001-04-01

We report the case of a hyoid syndrome caused by a developmental anomaly of the second branchial cleft, presenting at adult age by dysphagia without any abnormality detected at the barium swallow and at naso-pharyngeal endoscopy, first examinations to perform in case of dysphagia. The MRI findings of this anomaly showed a hyperintense well-limited vallecular mass syndrome. The diagnosis of hyoid bone anomaly was established at spiral CT with 3-D reconstructions showing an incurvated and elongated lesser cornua causing persistent impingement on the lateral wall of the oropharynx. CT scan performed during Valsalva maneuver showed the persistence of the compression during pharyngeal insufflation. (author)

International Uranium Resources Evaluation Project (IUREP) national favourability studies: Bolivia

International Nuclear Information System (INIS)

1977-08-01

Bolivia has an area of 1,098,580 square kilometers. Its capital is La Paz. The western part of the country is dominated by two ranges of the Andes Mountains, the Cordillera Occidental on the vest flank of the high plateau (Altiplano) and the Cordillera Real (or Oriental) on the east flank. The northern Andes average 5,486 meters in elevation; the southern Andes are not as lofty. The Altiplano is 3,658 to A,267 meters high and 129 km. in average width; it is the largest basin of inland drainage in South America and contains the renowned Lake Titicaca on the Peruvian-Bolivian border. The eastern tropical lowlands or pampas (Oriente) comprise about two-thirds of the country, with rain forest in the northern portion. An intermediate zone of valleys and basins lies between the eastern Andes and Oriente. Bolivia differs from other Andean countries, like Chile, Peru and Ecuador, in having large areas of Preeambrian schists, gneisses, migmatites and granites. These crop out in the eastern part of the country. Parts of these rocks contain banded iron formations (i.e., in the Muttin region) and are probably early Precambrian in age. Little systematic exploration for uranium was undertaken in Bolivia until the late 1960's. In 1967, 1968 and 1969 technical assistance was requested from, and provided by, the IAEA. This work led to evaluation of radioactive anomalies in veins of northeast Bolivia and in sandstones in the extreme southern part of the country. Although no uranium reserves are now credited to Bolivia, the geologic possibilities for several kinds of uranium deposits coupled with the relatively limited work done to date suggest that uranium orebodies will be discovered. It is estimated that the potential resources of Bolivia are in the range of 10,000 to 100,000 tonnes uranium

Uranium

International Nuclear Information System (INIS)

Mackay, G.A.

1978-01-01

The author discusses the contribution made by various energy sources in the production of electricity. Estimates are made of the future nuclear contribution, the future demand for uranium and future sales of Australian uranium. Nuclear power growth in the United States, Japan and Western Europe is discussed. The present status of the six major Australian uranium deposits (Ranger, Jabiluka, Nabarlek, Koongarra, Yeelerrie and Beverley) is given. Australian legislation relevant to the uranium mining industry is also outlined

Airborne gamma-ray spectrometer and magnetometer survey: Mariposa quadrangle (California, Nevada). Final report

International Nuclear Information System (INIS)

1980-01-01

A total of 15 uranium anomalies meet the minimum statistical requirements as defined in Volume I. These anomalies are shown on the Uranium Anomaly Interpretation Map, together with interpretation of the magnetic data. Potassium (K), equivalent uranium (eU), equivalent thorium (eTh), eU/eTh, eU/K, eTh/K, and magnetic Pseudo Contour Maps are presented in Appendix E. Stacked Profiles showing geologic strip maps along each flight line together with sensor data, and ancillary data are presented in Appendix F. All maps and profiles were prepared on a scale of 1:250,000, but have been reduced to 1:500,000 for presentation in Volume II. The anomaly map shows postulated magnetic discontinuities, the outline of shallow magnetic bodies responsible for short wavelength anomalies, and the outline of deep magnetic bodies responsible for the longer wavelength anomalies. The predominant trend in the magnetic discontinuities is north to northwest, which correlates well with the trend of mapped faults in the area. These magnetic discontinuities are interpreted as faults. A second set of east-northeast trending discontinuities off-sets the north to northwest trending set, and are interpreted as faults. The sources of several short wavelength anomalies are Quaternary and Jurassic/Triassic basic volcanic rocks. Longer wavelength anomalies present in the magnetic data are attributed to deep-seated basic igneous rocks

Clustering and Recurring Anomaly Identification: Recurring Anomaly Detection System (ReADS)

Science.gov (United States)

McIntosh, Dawn

2006-01-01

This viewgraph presentation reviews the Recurring Anomaly Detection System (ReADS). The Recurring Anomaly Detection System is a tool to analyze text reports, such as aviation reports and maintenance records: (1) Text clustering algorithms group large quantities of reports and documents; Reduces human error and fatigue (2) Identifies interconnected reports; Automates the discovery of possible recurring anomalies; (3) Provides a visualization of the clusters and recurring anomalies We have illustrated our techniques on data from Shuttle and ISS discrepancy reports, as well as ASRS data. ReADS has been integrated with a secure online search

Uranium - the nuclear fuel

International Nuclear Information System (INIS)

Smith, E.E.N.

1976-01-01

A brief history is presented of Canadian uranium exploration, production, and sales. Statistics show that Canada is a good customer for its own uranium due to a rapidly expanding nuclear power program. Due to an average 10 year lag between commencement of exploration and production, and with current producers sold out through 1985, it is imperative that exploration efforts be increased. (E.C.B.)

Czechoslovak uranium

International Nuclear Information System (INIS)

Pluskal, O.

1992-01-01

Data and knowledge related to the prospecting, mining, processing and export of uranium ores in Czechoslovakia are presented. In the years between 1945 and January 1, 1991, 98,461.1 t of uranium were extracted. In the period 1965-1990 the uranium industry was subsidized from the state budget to a total of 38.5 billion CSK. The subsidies were put into extraction, investments and geologic prospecting; the latter was at first, ie. till 1960 financed by the former USSR, later on the two parties shared costs on a 1:1 basis. Since 1981 the prospecting has been entirely financed from the Czechoslovak state budget. On Czechoslovak territory uranium has been extracted from deposits which may be classified as vein-type deposits, deposits in uranium-bearing sandstones and deposits connected with weathering processes. The future of mining, however, is almost exclusively being connected with deposits in uranium-bearing sandstones. A brief description and characteristic is given of all uranium deposits on Czechoslovak territory, and the organization of uranium mining in Czechoslovakia is described as is the approach used in the world to evaluate uranium deposits; uranium prices and actual resources are also given. (Z.S.) 3 figs

Uranium in Niger; L'uranium au Niger

Energy Technology Data Exchange (ETDEWEB)

Gabelmann, E

1978-03-15

This document presents government policy in the enhancement of uranium resources, existing mining companies and their productions, exploitation projects and economical outcome related to the uranium mining and auxiliary activities. [French] Le document presente la politique de l'Etat dans le cadre de la mise en valeur des ressources d'uranium, les societes minieres existantes et leurs productions, les projets d'exploitation d'uranium et les retombees economiques liees aux activites uraniferes et connexes.

Tracheobronchial Branching Anomalies

International Nuclear Information System (INIS)

Hong, Min Ji; Kim, Young Tong; Jou, Sung Shick; Park, A Young

2010-01-01

There are various congenital anomalies with respect to the number, length, diameter, and location of tracheobronchial branching patterns. The tracheobronchial anomalies are classified into two groups. The first one, anomalies of division, includes tracheal bronchus, cardiac bronchus, tracheal diverticulum, pulmonary isomerism, and minor variations. The second one, dysmorphic lung, includes lung agenesis-hypoplasia complex and lobar agenesis-aplasia complex

Tracheobronchial Branching Anomalies

Energy Technology Data Exchange (ETDEWEB)

Hong, Min Ji; Kim, Young Tong; Jou, Sung Shick [Soonchunhyang University, Cheonan Hospital, Cheonan (Korea, Republic of); Park, A Young [Soonchunhyang University College of Medicine, Asan (Korea, Republic of)

2010-04-15

There are various congenital anomalies with respect to the number, length, diameter, and location of tracheobronchial branching patterns. The tracheobronchial anomalies are classified into two groups. The first one, anomalies of division, includes tracheal bronchus, cardiac bronchus, tracheal diverticulum, pulmonary isomerism, and minor variations. The second one, dysmorphic lung, includes lung agenesis-hypoplasia complex and lobar agenesis-aplasia complex

Mise en solution et précipitation de l'uranium et du thorium dans les conditions de moyenne et haute température (résumé Solution and Precipitation of Uranium and Thorium under Average and High-Temperature (Summary

Directory of Open Access Journals (Sweden)

Moreau M.

2006-11-01

Full Text Available Les études tant analytiques qu'expérimentales réalisées au cours des vingt dernières années ont bien montré le rôle joué par les complexes d'uranylcarbonates dans le transport de l'uranium en milieu hydrothermal oxydant ou faiblement réducteur. Les travaux expérimentaux actuels sur la mobilité de U et Th, à haute température et haute pression, montrent la très grande différence de solubilité entre UO2 et ThO2, comme l'influence des ions complexants et celles de fO2 et aH+. Ces résultats expérimentaux sont comparés aux données recueillies sur les leucogranites et les granites calcoalcalins (France et divers gisements ou anomalies en uranium (Québec, Rössing, Madagascar, etc.. Dans la catazone U et Th précipitent sous forme de solutions solides d'uranothorianite dans les milieux déficitaires en silice, et sous forme d'uranothorite dans les granites et les syénites La précipitation d'uraninite non thorifère dans les leucogranites français s'explique d'abord par la faible concentration en thorium des solutions aqueuses durant la phase deutérique. Au cours du métamorphisme progressif on peut observer un retard dans la mobilisation de l'uranium en conditions relativement oxydantes, quand U est associé à Ti et OH. Dans le domaine mésozonal la brannérite stabilise l'uranium en présence de titane jusqu'à l'anatexie. Au-delà elle se dissocie en donnant de l'uraninite non thorifère et du rutile. Both analytic and experimental research done over the Iast twenty years has revealed the role played by uranylcarbonate complexes in the transfer of uranium in an oxidant or slightly reducing hydrothermal medium. Recent experimental research on the mobility of U and Th, at high temperature and high pressure, shows the great difference in solubility between UO2 and ThO2, like the influence of complexing ions and of fO2 and aH+. These experimental findings are compared to data gathered on leucogranites and colcoalkaline granites

Branchial anomalies in children.

Science.gov (United States)

Bajaj, Y; Ifeacho, S; Tweedie, D; Jephson, C G; Albert, D M; Cochrane, L A; Wyatt, M E; Jonas, N; Hartley, B E J

2011-08-01

Branchial cleft anomalies are the second most common head and neck congenital lesions seen in children. Amongst the branchial cleft malformations, second cleft lesions account for 95% of the branchial anomalies. This article analyzes all the cases of branchial cleft anomalies operated on at Great Ormond Street Hospital over the past 10 years. All children who underwent surgery for branchial cleft sinus or fistula from January 2000 to December 2010 were included in this study. In this series, we had 80 patients (38 female and 42 male). The age at the time of operation varied from 1 year to 14 years. Amongst this group, 15 patients had first branchial cleft anomaly, 62 had second branchial cleft anomaly and 3 had fourth branchial pouch anomaly. All the first cleft cases were operated on by a superficial parotidectomy approach with facial nerve identification. Complete excision was achieved in all these first cleft cases. In this series of first cleft anomalies, we had one complication (temporary marginal mandibular nerve weakness. In the 62 children with second branchial cleft anomalies, 50 were unilateral and 12 were bilateral. In the vast majority, the tract extended through the carotid bifurcation and extended up to pharyngeal constrictor muscles. Majority of these cases were operated on through an elliptical incision around the external opening. Complete excision was achieved in all second cleft cases except one who required a repeat excision. In this subgroup, we had two complications one patient developed a seroma and one had incomplete excision. The three patients with fourth pouch anomaly were treated with endoscopic assisted monopolar diathermy to the sinus opening with good outcome. Branchial anomalies are relatively common in children. There are three distinct types, first cleft, second cleft and fourth pouch anomaly. Correct diagnosis is essential to avoid inadequate surgery and multiple procedures. The surgical approach needs to be tailored to the type

Geophysical exploration for uranium in Champaner group of rocks, Panchmahals district, Gujarat, India: a case study

International Nuclear Information System (INIS)

Narasimha Rao, R.L.; Sethuram, S.; Markandeyulu, A.; Chakraborty, K.; Tiku, K.L.

1997-01-01

Geophysical investigations comprising gravity, magnetic, resistivity and induced polarization methods were carried out at Garumal, Panchmahals district, Gujarat, where uranium mineralisation occurs in Champaner group of rocks as fracture controlled veins along the axial zone of a WNW-ESE plunging fold. The distinct break in the Bouguer gravity contour map signifies a lineament within the Champaner group of rocks and this probably represents a mega-fracture. Sharp magnetic anomalies forming a ring and the associated high resistivity characterize an acidic intrusive body, the probable source for the uranium mineralisation occurring in this area. Resistivity contour map delineates the lithic boundaries distinctly. The linear magnetic feature observed over a strike length of 2.5 km represents a small scale skarn-type iron ore deposit. (author)

Exploration of the Key Lake uranium deposits, Saskatchewan, Canada

International Nuclear Information System (INIS)

Gatzweiler, R.; Schmeling, B.; Tan, B.

1981-01-01

In 1969, one year after the discovery of the Rabbit Lake uranium deposit, exploration started in the Key Lake area as part of a major uranium rush into Northern Saskatchewan, and within the frame of a joint venture. The area was not chosen on the basis of a particular metallogenetic concept. The lack of exploratory success in 1969 and 1970, together with the introduction in March 1970 of foreign ownership restrictions for uranium mining in Canada, discouraged six of the nine companies forming the original joint venture. In 1971 the three remaining companies decided to continue under a redefined concept, based on the knowledge obtained from the Rabbit Lake deposit (Uranerz had acquired a 49% share in 1970) and from the newly discovered uranium deposits in the Pine Creek Geosyncline, Australia. In the same year, exploration work resulted in the discovery of two high-grade mineralized boulders and significant radioactive and geochemical anomalies 5 km SW of Key Lake deposits. Subsequent exploration, aimed at finding the source of the mineralized boulders, comprised geological, glacial geological and ground radiometric surveys, boulder tracing, air-photo interpretation, lake sediment and muskeg sampling surveys, radon surveys, ground magnetic, gravity, electromagnetic and IP surveys, and drilling. The systematic exploration efforts resulted in the discovery of the Gaertner ore body in July 1975 and the Deilmann ore body in June 1976, where glacial geology, lake sediment sampling, magnetic and electromagnetic surveys were the key methods in defining the drilling targets. Three further years and a total of about 2400 drillholes were needed to fully delineate the two ore bodies. (author)

Uranium favorability of tertiary sedimentary rocks of the western Okanogan highlands and of the upper Columbia River valley, Washington. [Measurement and sampling of surface sections, collection of samples from isolated outcrops, and chemical and mineralogical analyses of samples; no known uranium deposits

Energy Technology Data Exchange (ETDEWEB)

Marjaniemi, D.K.; Robins, J.W.

1975-08-01

Tertiary sedimentary rocks in the northern portions of the western Okanogan highlands and in the upper Columbia River valley were investigated during a regional study to determine the favorability for potential uranium resources of the Tertiary sedimentary rocks of northeastern Washington. This project involved measurement and sampling of surface sections, collection of samples from isolated outcrops, and chemical and mineralogical analyses of samples. No portion of the project area of this report is rated of high or of medium favorability for potential uranium resources. Low favorability ratings are given to Oroville, Tonasket, and Pine Creek areas of the Okanogan River valley; to the Republic graben; and to the William Lakes, Colville, and Sheep Creek areas of the upper Columbia River valley. All these areas contain some fluvial, poorly sorted feldspathic or arkosic sandstones and conglomerates. These rocks are characterized by very low permeability and a consistently high siliceous matrix suggesting very low initial permeability. There are no known uranium deposits in any of these areas, and low level uranium anomalies are rare.

Uranium ores

International Nuclear Information System (INIS)

Poty, B.; Roux, J.

1998-01-01

The processing of uranium ores for uranium extraction and concentration is not much different than the processing of other metallic ores. However, thanks to its radioactive property, the prospecting of uranium ores can be performed using geophysical methods. Surface and sub-surface detection methods are a combination of radioactive measurement methods (radium, radon etc..) and classical mining and petroleum prospecting methods. Worldwide uranium prospecting has been more or less active during the last 50 years, but the rise of raw material and energy prices between 1970 and 1980 has incited several countries to develop their nuclear industry in order to diversify their resources and improve their energy independence. The result is a considerable increase of nuclear fuels demand between 1980 and 1990. This paper describes successively: the uranium prospecting methods (direct, indirect and methodology), the uranium deposits (economical definition, uranium ores, and deposits), the exploitation of uranium ores (use of radioactivity, radioprotection, effluents), the worldwide uranium resources (definition of the different categories and present day state of worldwide resources). (J.S.)

Environmental monitoring of uranium mining wastes using geophysical techniques-Phase 1

International Nuclear Information System (INIS)

Koch, R.R.

1996-08-01

Monitoring of contaminants, from uranium mine waste management facilities, is primarily done by drilling test holes and installing piezometers to sample the subsurface soil and the groundwater. Protocols using geophysical methods of monitoring the migration of acidic leachate from uranium mine waste rock piles and tailings facilities need to be developed. Shallow surface geophysics that include methods such as Electromagnetic (conductivity) and DC Resistivity surveys are less expensive, can locate contaminant plumes both laterally and with depth, providing an areal 'snapshot' of the site at any given time. Cluff Lake Mine, a wholly owned Cogema Resources Inc. of Sakatoon was selected as the research demonstration site. To study the effects of acidic mine drainage a multi-year program is envisioned. The first phase, the subject of this report, involved the testing of various off-the-shelf elctromagnetic and restivity equipment over several site locations. Additional phases are required to monitor temporal changes by carrying out repeat surveys to verify the first phase results. Other methods such as ground penetrating radar may be used to supplement the conductivity and restivity surveys. Electromagnetic surveys identified three conductive zones in the vicinity of the Claude waste rock pile. These anomalies appear to be confined to within 100-150 meters of the pile. A significant area of high conductivity was identified adjacent to the liquid tailings pond on the ED-TDAM-1 grid. Conductivity zones were not detected on grids in the vicinity of the OP waste rock pile and the STS ponds site. The imaged pseudosections of apparent resistivity not only correlate well with the apparent conductivity data at the same locations, but supply information with the anomalies in the third (depth) dimension. On Line 25W of EV-TDAM-1 site the restivity survey indicates that the main anomaly A (450N) has a depth of > 6 metres. Computer assisted inversion and interpretation of sounding

Calcium isotopic anomalies in the Allende meteorite

International Nuclear Information System (INIS)

Lee, T.; Papanastassiou, D.A.; Wasserburg, G.J.

1978-01-01

We report isotopic anomalies in Ca which were found in two Ca-Al-rich inclusions of the Allende meteorite. These inclusions previously had been shown to contain special anomalies for Mg and O which were attributed to fractionation and unknown nuclear effects. The Ca data, when corrected for mass fractionation by using 40 Ca/ 44 Ca as a standard, show nonlinear isotopic effects in 48 Ca of +13.5 per mil and in 42 Ca of +1.7 per mil for one sample. The second sample shows a 48 Ca depletion of -2.9 per mil, but all other isotopes are normal. Samples with large excesses in 26 Mg show no Ca anomalies. The effects demonstrate that isotopic anomalies exist for higher-atomic-number refractory elements in solar-system materials and do not appear to be readily explainable by a simple model. The correlation of O, Mg, and Ca results on the same inclusions requires the addition and preservation in the solar system of components from idverse nucleosynthetic sources. Observed anomalous Mg and Ca compositions for coexisting mineral phases are uniform within each inclusion, and require initial isotopic homogeneity within an inclusion but the preservation of wide variations between inclusions. Assuming formation of these inclusions by condensation from a gaseous part of the solar nebula, this implies isotopic heterogeneity on a scale of 10-10 2 km within the nebula

Uranium association with halophilic and non-halophilic bacteria and archaea

International Nuclear Information System (INIS)

Francis, A.J.; Gillow, J.B.; Dodge, C.J.; Harris, R.; Beveridge, T.J.; Papenguth, H.W.

2004-01-01

We determined the association of uranium with bacteria isolated from the Waste Isolation Pilot Plant (WIPP), Carlsbad, New Mexico, and compared this with known strains of halophilic and non-halophilic bacteria and archaea. Examination of the cultures by transmission electron microscopy (TEM) and energy dispersive X-ray spectroscopy (EDS) showed uranium accumulation extracellularly and/or intracellularly to a varying degree. In Pseudomonas fluorescens and Bacillus subtilis uranium was associated with the cell surface and in the latter it was present as irregularly shaped grains. In Halobacterium halobium, the only archeon studied here, uranium was present as dense deposits and with Haloanaerobium praevalens as spikey deposits. Halomonas sp. isolated from the WIPP site accumulated uranium both extracellularly on the cell surface and intracellularly as electron-dense discrete granules. Extended X-ray absorption fine structure (EXAFS) analysis of uranium with the halophilic and non-halophilic bacteria and archaea showed that the uranium present in whole cells was bonded to an average of 2.4 ± 0.7 phosphoryl groups at a distance of 3.65 ± 0.03 Aa. Comparison of whole cells of Halomonas sp. with the cell wall fragments of lysed cells showed the presence of a uranium bidentate complex at 2.91 ± 0.03 Aa with the carboxylate group on the cell wall, and uranyl hydroxide with U-U interaction at 3.71 ± 0.03 Aa due to adsorption or precipitation reactions; no U-P interaction was observed. Addition of uranium to the cell lysate of Halomonas sp. resulted in the precipitation of uranium due to the inorganic phosphate produced by the cells. These results show that the phosphates released from bacteria bind a significant amount of uranium. However, the bacterially immobilized uranium was readily solubilized by bicarbonate with concurrent release of phosphate into solution. (orig.)

Uranium favorability of tertiary sedimentary rocks of the western Okanogan highlands and of the upper Columbia River valley, Washington

International Nuclear Information System (INIS)

Marjaniemi, D.K.; Robins, J.W.

1975-08-01

Tertiary sedimentary rocks in the northern portions of the western Okanogan highlands and in the upper Columbia River valley were investigated during a regional study to determine the favorability for potential uranium resources of the Tertiary sedimentary rocks of northeastern Washington. This project involved measurement and sampling of surface sections, collection of samples from isolated outcrops, and chemical and mineralogical analyses of samples. No portion of the project area of this report is rated of high or of medium favorability for potential uranium resources. Low favorability ratings are given to Oroville, Tonasket, and Pine Creek areas of the Okanogan River valley; to the Republic graben; and to the William Lakes, Colville, and Sheep Creek areas of the upper Columbia River valley. All these areas contain some fluvial, poorly sorted feldspathic or arkosic sandstones and conglomerates. These rocks are characterized by very low permeability and a consistently high siliceous matrix suggesting very low initial permeability. There are no known uranium deposits in any of these areas, and low level uranium anomalies are rare

Symmetric scaling properties in global surface air temperature anomalies

Science.gov (United States)

Varotsos, Costas A.; Efstathiou, Maria N.

2015-08-01

We have recently suggested "long-term memory" or internal long-range correlation within the time-series of land-surface air temperature (LSAT) anomalies in both hemispheres. For example, an increasing trend in the LSAT anomalies is followed by another one at a different time in a power-law fashion. However, our previous research was mainly focused on the overall long-term persistence, while in the present study, the upward and downward scaling dynamics of the LSAT anomalies are analysed, separately. Our results show that no significant fluctuation differences were found between the increments and decrements in LSAT anomalies, over the whole Earth and over each hemisphere, individually. On the contrary, the combination of land-surface air and sea-surface water temperature anomalies seemed to cause a departure from symmetry and the increments in the land and sea surface temperature anomalies appear to be more persistent than the decrements.

Uranium leads political stakes

International Nuclear Information System (INIS)

James, D.

2009-01-01

Until the announcement by the federal Environment Minister Peter Garrett that the government would permit uranium mining at Beverly Four Mile, South Australia, there had been little news flow from the sector over the past year. Uranium was the first to turn down, even before the United States sub-prime mortgage crisis began to cause shock waves through the global economy, a report by BGF Equities analyst Warwick Grigor shows.

Uranium uptake by hydroponically cultivated crop plants

Energy Technology Data Exchange (ETDEWEB)

Soudek, Petr; Petrova, Sarka [Laboratory of Plant Biotechnologies, Joint Laboratory of Institute of Experimental Botany AS CR, v.v.i. and Crop Research Institute, v.v.i., Rozvojova 263, 162 05 Prague 6 (Czech Republic); Benesova, Dagmar [Laboratory of Plant Biotechnologies, Joint Laboratory of Institute of Experimental Botany AS CR, v.v.i. and Crop Research Institute, v.v.i., Rozvojova 263, 162 05 Prague 6 (Czech Republic); Faculty of Environment Technology, Institute of Chemical Technology, Technicka 5, 166 28 Prague 6 (Czech Republic); Dvorakova, Marcela [Laboratory of Plant Biotechnologies, Joint Laboratory of Institute of Experimental Botany AS CR, v.v.i. and Crop Research Institute, v.v.i., Rozvojova 263, 162 05 Prague 6 (Czech Republic); Vanek, Tomas, E-mail: vanek@ueb.cas.cz [Laboratory of Plant Biotechnologies, Joint Laboratory of Institute of Experimental Botany AS CR, v.v.i. and Crop Research Institute, v.v.i., Rozvojova 263, 162 05 Prague 6 (Czech Republic)

2011-06-15

Hydroponicaly cultivated plants were grown on medium containing uranium. The appropriate concentrations of uranium for the experiments were selected on the basis of a standard ecotoxicity test. The most sensitive plant species was determined to be Lactuca sativa with an EC{sub 50} value about 0.1 mM. Cucumis sativa represented the most resistant plant to uranium (EC{sub 50} = 0.71 mM). Therefore, we used the uranium in a concentration range from 0.1 to 1 mM. Twenty different plant species were tested in hydroponic solution supplemented by 0.1 mM or 0.5 mM uranium concentration. The uranium accumulation of these plants varied from 0.16 mg/g DW to 0.011 mg/g DW. The highest uranium uptake was determined for Zea mays and the lowest for Arabidopsis thaliana. The amount of accumulated uranium was strongly influenced by uranium concentration in the cultivation medium. Autoradiography showed that uranium is mainly localized in the root system of the plants tested. Additional experiments demonstrated the possibility of influencing the uranium uptake from the cultivation medium by amendments. Tartaric acid was able to increase uranium uptake by Brassica oleracea and Sinapis alba up to 2.8 times or 1.9 times, respectively. Phosphate deficiency increased uranium uptake up to 4.5 times or 3.9 times, respectively, by Brassica oleracea and S. alba. In the case of deficiency of iron or presence of cadmium ions we did not find any increase in uranium accumulation. - Highlights: > The uranium accumulation in twenty different plant species varied from 0.160 to 0.011 mg/g DW. > Uranium is mainly localized in the root system. > Tartaric acid was able to increase uranium uptake by Brassica oleracea and Sinapis alba. > The phosphates deficiency increase the uranium uptake.

Uranium uptake by hydroponically cultivated crop plants

International Nuclear Information System (INIS)

Soudek, Petr; Petrova, Sarka; Benesova, Dagmar; Dvorakova, Marcela; Vanek, Tomas

2011-01-01

Hydroponicaly cultivated plants were grown on medium containing uranium. The appropriate concentrations of uranium for the experiments were selected on the basis of a standard ecotoxicity test. The most sensitive plant species was determined to be Lactuca sativa with an EC 50 value about 0.1 mM. Cucumis sativa represented the most resistant plant to uranium (EC 50 = 0.71 mM). Therefore, we used the uranium in a concentration range from 0.1 to 1 mM. Twenty different plant species were tested in hydroponic solution supplemented by 0.1 mM or 0.5 mM uranium concentration. The uranium accumulation of these plants varied from 0.16 mg/g DW to 0.011 mg/g DW. The highest uranium uptake was determined for Zea mays and the lowest for Arabidopsis thaliana. The amount of accumulated uranium was strongly influenced by uranium concentration in the cultivation medium. Autoradiography showed that uranium is mainly localized in the root system of the plants tested. Additional experiments demonstrated the possibility of influencing the uranium uptake from the cultivation medium by amendments. Tartaric acid was able to increase uranium uptake by Brassica oleracea and Sinapis alba up to 2.8 times or 1.9 times, respectively. Phosphate deficiency increased uranium uptake up to 4.5 times or 3.9 times, respectively, by Brassica oleracea and S. alba. In the case of deficiency of iron or presence of cadmium ions we did not find any increase in uranium accumulation. - Highlights: → The uranium accumulation in twenty different plant species varied from 0.160 to 0.011 mg/g DW. → Uranium is mainly localized in the root system. → Tartaric acid was able to increase uranium uptake by Brassica oleracea and Sinapis alba. → The phosphates deficiency increase the uranium uptake.

Pengaruh Kandungan Uranium Dalam Umpan Terhadap Efisiensi Pengendapan Uranium

OpenAIRE

Torowati

2010-01-01

PENGARUH KANDUNGAN URANIUM DALAM UMPAN TERHADAP EFISIENSI PENGENDAPAN URANIUM. Setiap aktivitas analisis di Laboratorium Kendali Kualitas, Bidang Bahan Bakar Nuklir selalu dihasilkan limbah radioaktif cair. Limbah radioaktif cair di laboratorium masih mengandung uranium yang cukup besar ± 0,600 g U/l dengan keasamaan yang cukup besar pula. Karena uranium mempunyai nilai ekonomis yang cukup tinggi maka perlu USAha untuk mengambil kembali uranium tersebut. Pada kegiatan ini telah dilak...

Actual and Idealized Crystal Field Parameterizations for the Uranium Ions in UF 4

Science.gov (United States)

Gajek, Z.; Mulak, J.; Krupa, J. C.

1993-12-01

The crystal field parameters for the actual coordination symmetries of the uranium ions in UF 4, C2 and C1, and for their idealizations to D2, C2 v , D4, D4 d , and the Archimedean antiprism point symmetries are given. They have been calculated by means of both the perturbative ab initio model and the angular overlap model and are referenced to the recent results fitted by Carnall's group. The equivalency of some different sets of parameters has been verified with the standardization procedure. The adequacy of several idealized approaches has been tested by comparison of the corresponding splitting patterns of the 3H 4 ground state. Our results support the parameterization given by Carnall. Furthermore, the parameterization of the crystal field potential and the splitting diagram for the symmetryless uranium ion U( C1) are given. Having at our disposal the crystal field splittings for the two kinds of uranium ions in UF 4, U( C2) and U( C1), we calculate the model plots of the paramagnetic susceptibility χ( T) and the magnetic entropy associated with the Schottky anomaly Δ S( T) for UF 4.

Glances on uranium. From uranium in the earth to electric power

International Nuclear Information System (INIS)

Valsardieu, C.

1995-01-01

This book is a technical, scientific and historical analysis of the nuclear fuel cycle from the origin of uranium in the earth and the exploitation of uranium ores to the ultimate storage of radioactive wastes. It comprises 6 chapters dealing with: 1) the different steps of uranium history (discovery, history of uranium chemistry, the radium era, the physicists and the structure of matter, the military uses, the nuclear power, the uranium industry and economics), 2) the uranium in nature (nuclear structure, physical-chemical properties, radioactivity, ores, resources, cycle, deposits), 3) the sidelights on uranium history (mining, prospecting, experience, ore processing, resources, reserves, costs), 4) the uranium in the fuel cycle, energy source and industrial product (fuel cycle, fission, refining, enrichment, fuel processing and reprocessing, nuclear reactors, wastes management), 5) the other energies in competition and the uranium market (other uranium uses, fossil fuels and renewable energies, uranium market), and 6) the future of uranium (forecasting, ecology, economics). (J.S.)

Thermal Expansion Anomaly Regulated by Entropy

Science.gov (United States)

Liu, Zi-Kui; Wang, Yi; Shang, Shunli

2014-11-01

Thermal expansion, defined as the temperature dependence of volume under constant pressure, is a common phenomenon in nature and originates from anharmonic lattice dynamics. However, it has been poorly understood how thermal expansion can show anomalies such as colossal positive, zero, or negative thermal expansion (CPTE, ZTE, or NTE), especially in quantitative terms. Here we show that changes in configurational entropy due to metastable micro(scopic)states can lead to quantitative prediction of these anomalies. We integrate the Maxwell relation, statistic mechanics, and first-principles calculations to demonstrate that when the entropy is increased by pressure, NTE occurs such as in Invar alloy (Fe3Pt, for example), silicon, ice, and water, and when the entropy is decreased dramatically by pressure, CPTE is expected such as in anti-Invar cerium, ice and water. Our findings provide a theoretic framework to understand and predict a broad range of anomalies in nature in addition to thermal expansion, which may include gigantic electrocaloric and electromechanical responses, anomalously reduced thermal conductivity, and spin distributions.

THE PREVALENCE OF DENTAL ANOMALIES IN A TURKISH POPULATION

Directory of Open Access Journals (Sweden)

Gamze Aren

2015-10-01

Full Text Available Purpose: The aim of the present study was to investigate the prevalence of dental anomalies in a Turkish population according to the gender and age. Materials and Methods: A retrospective study was performed using panoramic radiographs of 2025 patients (885 males and 1140 females ranging in age from 9 to 35 (mean age 25.61±10.04 years attending Department of Oral Radiology, University of Istanbul, Faculty of Dentistry. These patients were examined to determine the presence of developmental dental anomalies involving hypodontia, hyperdontia, microdontia, taurodontism and other root anomalies. The incidence of these anomalies were assessed according to the gender and age. Results: Among the 2025 subjects, a total of 96 individuals (42 males and 54 females showed at least one of the selected dental anomalies (4.74%. Tooth agenesis was the most common dental abnormality (1.77% followed by taurodontism (1.18%, hyperdontia (0.79%, microdontia (0.54% and root anomalies (0.44%, respectively. Conclusion: Tooth agenesis is the most common developmental dental anomaly in the studied Turkish population followed by taurodontism.

The prevalence of dental anomalies in a turkish population.

Science.gov (United States)

Aren, Gamze; Guven, Yeliz; Guney Tolgay, Ceren; Ozcan, Ilknur; Bayar, Ozlem Filiz; Kose, Taha Emre; Koyuncuoglu, Gulhan; Ak, Gulsum

2015-01-01

The aim of the present study was to investigate the prevalence of dental anomalies in a Turkish population according to the gender and age. A retrospective study was performed using panoramic radiographs of 2025 patients (885 males and 1140 females) ranging in age from 9 to 35 (mean age 25.61±10.04) years attending Department of Oral Radiology, University of Istanbul, Faculty of Dentistry. These patients were examined to determine the presence of developmental dental anomalies involving hypodontia, hyperdontia, microdontia, taurodontism and other root anomalies. The incidence of these anomalies were assessed according to the gender and age. Among the 2025 subjects, a total of 96 individuals (42 males and 54 females) showed at least one of the selected dental anomalies (4.74%). Tooth agenesis was the most common dental abnormality (1.77%) followed by taurodontism (1.18%), hyperdontia (0.79%), microdontia (0.54%) and root anomalies (0.44%), respectively. Tooth agenesis is the most common developmental dental anomaly in the studied Turkish population followed by taurodontism.

The uranium provinces of the Lagoa Real District-Bahia (Brazil)

International Nuclear Information System (INIS)

Geisel Sobrinho, E.; Raposo, C.; Alves, J.V.; Brito, W. de; Vasconcelos, T.G.

1980-01-01

The Lagoa Real Project from NUCLEBRAS represents one of the most important uranium provinces in Brazil today. The project is limited by the 42 0 00' - 42 0 30'W and 13 0 30' - 14 0 15'S geographic coordinates, covering an area of 4,540 square kilometres in the South-Central part of Bahia State. Since 1977, 13 radiometric anomalies have been detected. As part of the Archean basement, metasomatized and cataclastic metamorphic rocks outcrop in the area. The uranium mineralization occurs in albitite bodies parallel to its foliation and is represented by fine grained uraninite. Lying roughly in N-S direction the albitite bodies are tabular and elongated. Each albitite body may reach over 1 Km of extensoin, 100m of width, and 350m of depth. 207 Pb/ 206 Pb age determination indicated 820 my as the age of uraninite crystallization. An ore reserve of 27,000 ton of U 3 O 8 at an average grade of 0.15% U 3 O 8 has been determined following geologic, topographic, and radiometric survey over an area of 700 hectares and the completion of 160 drill-holes totalizing 23,000 metres. The potential uranium reserve of the Lagoa Real District has not as yet been properly evaluated because from the known orebodies only six have been sistematically investigated to date. (Author) [pt

Fission track method for uranium ore exploration

International Nuclear Information System (INIS)

Guo Shilun; Deng Xinlu; Sun Shengfen; Meng Wu; Zhang Pengfa; Hao Xiuhong

1986-01-01

The uranium concentrations in natural water collected in the fields of uranium ore exploration with fission track method have been determined. It shows that the results of fission track method are consistent with that of fluoro-colorimetry and laser fluorometry for the same samples of water with uranium concentration in the region of 10 -4 to 10 -8 g/l. For water samples with lower uranium concentration (≤10 -8 g/l), the fission track method can still give accurate or referential results, but the other two methods failed. The reproducibility of fission track method was checked and discussed by using samples collected in the same fields of uranium ore exploration. The effects of the concentration of the impurities in natural water on determination of uranium concentration were analysed and discussed as well

Treatment of uranium-containing effluent in the process of metallic uranium parts

International Nuclear Information System (INIS)

Yuan Guoqi

1993-01-01

The anion exchange method used in treatment of uranium-containing effluent in the process of metallic parts is the subject of the paper. The results of the experiments shows that the uranium concentration in created water remains is less than 10 μg/l when the waste water flowed through 10000 column volume. A small facility with column volume 150 litre was installed and 1500 m 3 of waste water can be cleaned per year. (1 tab.)

Translocation of uranium from water to foodstuff while cooking

International Nuclear Information System (INIS)

Krishnapriya, K.C.; Baksi, Ananya; Chaudhari, Swathi; Gupta, Soujit Sen; Pradeep, T.

2015-01-01

Highlights: • Rice can efficiently uptake uranium from water contaminated with uranyl nitrate hexahydrate (UO 2 (NO 3 ) 2.6 H 2 O), while cooking. • Unusual uranium uptake to the extent of about 1000 ppm is observed when rice is cooked in highly concentrated uranium contaminated water (1240 ppm). • Nature of interaction of uranium with carbohydrates is probed using small monosaccharides like glucose and mannose. • Electrospray ionization mass spectrometry showed UO 2 2+ to be the most stable species in water in such solutions which can form complexes with sugars. • The species (UO 2 2+ ) is also observed in the case of water exposed to the common mineral, uranium oxide (UO 2 ) and similar type of complexation is observed with sugars. - Abstract: The present work report the unusual uranium uptake by foodstuff, especially those rich in carbohydrates like rice when they are cooked in water, contaminated with uranium. The major staple diet in South Asia, rice, was chosen to study its interaction with UO 2 2+ , the active uranium species in water, using inductively coupled plasma mass spectrometry. Highest uptake limit was checked by cooking rice at very high uranium concentration and it was found to be good scavenger of uranium. To gain insight into the mechanism of uptake, direct interaction of UO 2 2+ with monosaccharides was also studied, using electrospray ionization mass spectrometry taking mannose as a model. The studies have been done with dissolved uranium salt, uranyl nitrate hexahydrate (UO 2 (NO 3 ) 2 ·6H 2 O), as well as the leachate of a stable oxide of uranium, UO 2 (s), both of which exist as UO 2 2+ in water. Among the eight different rice varieties investigated, Karnataka Ponni showed the maximum uranium uptake whereas unpolished Basmati rice showed the minimum. Interaction with other foodstuffs (potato, carrot, peas, kidney beans and lentils) with and without NaCl affected the extent of chemical interaction but was not consistent with the

Flavorful hybrid anomaly-gravity mediation

International Nuclear Information System (INIS)

Gross, Christian; Hiller, Gudrun

2011-01-01

We consider supersymmetric models where anomaly and gravity mediation give comparable contributions to the soft terms and discuss how this can be realized in a five-dimensional brane world. The gaugino mass pattern of anomaly mediation is preserved in such a hybrid setup. The flavorful gravity-mediated contribution cures the tachyonic slepton problem of anomaly mediation. The supersymmetric flavor puzzle is solved by alignment. We explicitly show how a working flavor-tachyon link can be realized with Abelian flavor symmetries and give the characteristic signatures of the framework, including O(1) slepton mass splittings between different generations and between doublets and singlets. This provides opportunities for same flavor dilepton edge measurements with missing energy at the Large Hadron Collider (LHC). Rare lepton decay rates could be close to their current experimental limit. Compared to pure gravity mediation, the hybrid model is advantageous because it features a heavy gravitino which can avoid the cosmological gravitino problem of gravity-mediated models combined with leptogenesis.

Uranium

International Nuclear Information System (INIS)

Stewart, E.D.J.

1974-01-01

A discussion is given of uranium as an energy source in The Australian economy. Figures and predictions are presented on the world supply-demand position and also figures are given on the added value that can be achieved by the processing of uranium. Conclusions are drawn about Australia's future policy with regard to uranium (R.L.)

Uranium, depleted uranium, biological effects

International Nuclear Information System (INIS)

2001-01-01

Physicists, chemists and biologists at the CEA are developing scientific programs on the properties and uses of ionizing radiation. Since the CEA was created in 1945, a great deal of research has been carried out on the properties of natural, enriched and depleted uranium in cooperation with university laboratories and CNRS. There is a great deal of available data about uranium; thousands of analyses have been published in international reviews over more than 40 years. This presentation on uranium is a very brief summary of all these studies. (author)

Uranium determination in dental ceramics

International Nuclear Information System (INIS)

Jacobson, I.; Gamboa, I.; Espinosa, G.; Moreno, A.

1984-01-01

There are many reports of high uranium concentration in dental ceramics, so they require to be controlled. The SSNTD is an optional method to determine the uranium concentration. In this work the analysis of several commercial dental ceramics used regularly in Mexico by dentists is presented. The chemical and electrochemical processes are used and the optimal conditions for high sensitivity are determined. CR-39 (allyl diglycol polycarbonate) was used as detector. The preliminary results show some materials with high uranium concentrations. Next step will be the analysis of equivalent dose and the effects in the public health. (author)

Translocation of uranium from water to foodstuff while cooking.

Science.gov (United States)

Krishnapriya, K C; Baksi, Ananya; Chaudhari, Swathi; Gupta, Soujit Sen; Pradeep, T

2015-10-30

The present work report the unusual uranium uptake by foodstuff, especially those rich in carbohydrates like rice when they are cooked in water, contaminated with uranium. The major staple diet in South Asia, rice, was chosen to study its interaction with UO2(2+), the active uranium species in water, using inductively coupled plasma mass spectrometry. Highest uptake limit was checked by cooking rice at very high uranium concentration and it was found to be good scavenger of uranium. To gain insight into the mechanism of uptake, direct interaction of UO2(2+) with monosaccharides was also studied, using electrospray ionization mass spectrometry taking mannose as a model. The studies have been done with dissolved uranium salt, uranyl nitrate hexahydrate (UO2(NO3)2·6H2O), as well as the leachate of a stable oxide of uranium, UO2(s), both of which exist as UO2(2+) in water. Among the eight different rice varieties investigated, Karnataka Ponni showed the maximum uranium uptake whereas unpolished Basmati rice showed the minimum. Interaction with other foodstuffs (potato, carrot, peas, kidney beans and lentils) with and without NaCl affected the extent of chemical interaction but was not consistent with the carbohydrate content. Uranium interaction with D-mannose monitored through ESI-MS, under optimized instrumental parameters, identified the peaks corresponding to uranyl adduct with mannose monomer, dimer and trimer and the species were confirmed by MS/MS studies. The product ion mass spectra showed peaks illustrating water loss from the parent ion as the collision energy was increased, an evidence for the strong interaction of uranium with mannose. This study would constitute the essential background for understanding interaction of uranium with various foods. Extension of this work would involve identification of foodstuff as green heavy metal scavengers. Copyright © 2015. Published by Elsevier B.V.

Uranium induces oxidative stress in lung epithelial cells

International Nuclear Information System (INIS)

Periyakaruppan, Adaikkappan; Kumar, Felix; Sarkar, Shubhashish; Sharma, Chidananda S.; Ramesh, Govindarajan T.

2007-01-01

Uranium compounds are widely used in the nuclear fuel cycle, antitank weapons, tank armor, and also as a pigment to color ceramics and glass. Effective management of waste uranium compounds is necessary to prevent exposure to avoid adverse health effects on the population. Health risks associated with uranium exposure includes kidney disease and respiratory disorders. In addition, several published results have shown uranium or depleted uranium causes DNA damage, mutagenicity, cancer and neurological defects. In the current study, uranium toxicity was evaluated in rat lung epithelial cells. The study shows uranium induces significant oxidative stress in rat lung epithelial cells followed by concomitant decrease in the antioxidant potential of the cells. Treatment with uranium to rat lung epithelial cells also decreased cell proliferation after 72 h in culture. The decrease in cell proliferation was attributed to loss of total glutathione and superoxide dismutase in the presence of uranium. Thus the results indicate the ineffectiveness of antioxidant system's response to the oxidative stress induced by uranium in the cells. (orig.)

Anomalies, conformal manifolds, and spheres

Energy Technology Data Exchange (ETDEWEB)

Gomis, Jaume [Perimeter Institute for Theoretical Physics,Waterloo, Ontario, N2L 2Y5 (Canada); Hsin, Po-Shen [Department of Physics, Princeton University,Princeton, NJ 08544 (United States); Komargodski, Zohar; Schwimmer, Adam [Weizmann Institute of Science,Rehovot 76100 (Israel); Seiberg, Nathan [School of Natural Sciences, Institute for Advanced Study,Princeton, NJ 08540 (United States); Theisen, Stefan [Max-Planck-Institut für Gravitationsphysik, Albert-Einstein-Institut,14476 Golm (Germany)

2016-03-04

The two-point function of exactly marginal operators leads to a universal contribution to the trace anomaly in even dimensions. We study aspects of this trace anomaly, emphasizing its interpretation as a sigma model, whose target space M is the space of conformal field theories (a.k.a. the conformal manifold). When the underlying quantum field theory is supersymmetric, this sigma model has to be appropriately supersymmetrized. As examples, we consider in some detail N=(2,2) and N=(0,2) supersymmetric theories in d=2 and N=2 supersymmetric theories in d=4. This reasoning leads to new information about the conformal manifolds of these theories, for example, we show that the manifold is Kähler-Hodge and we further argue that it has vanishing Kähler class. For N=(2,2) theories in d=2 and N=2 theories in d=4 we also show that the relation between the sphere partition function and the Kähler potential of M follows immediately from the appropriate sigma models that we construct. Along the way we find several examples of potential trace anomalies that obey the Wess-Zumino consistency conditions, but can be ruled out by a more detailed analysis.

Solubility measurement of uranium in uranium-contaminated soils

International Nuclear Information System (INIS)

Lee, S.Y.; Elless, M.; Hoffman, F.

1993-08-01

A short-term equilibration study involving two uranium-contaminated soils at the Fernald site was conducted as part of the In Situ Remediation Integrated Program. The goal of this study is to predict the behavior of uranium during on-site remediation of these soils. Geochemical modeling was performed on the aqueous species dissolved from these soils following the equilibration study to predict the on-site uranium leaching and transport processes. The soluble levels of total uranium, calcium, magnesium, and carbonate increased continually for the first four weeks. After the first four weeks, these components either reached a steady-state equilibrium or continued linearity throughout the study. Aluminum, potassium, and iron, reached a steady-state concentration within three days. Silica levels approximated the predicted solubility of quartz throughout the study. A much higher level of dissolved uranium was observed in the soil contaminated from spillage of uranium-laden solvents and process effluents than in the soil contaminated from settling of airborne uranium particles ejected from the nearby incinerator. The high levels observed for soluble calcium, magnesium, and bicarbonate are probably the result of magnesium and/or calcium carbonate minerals dissolving in these soils. Geochemical modeling confirms that the uranyl-carbonate complexes are the most stable and dominant in these solutions. The use of carbonate minerals on these soils for erosion control and road construction activities contributes to the leaching of uranium from contaminated soil particles. Dissolved carbonates promote uranium solubility, forming highly mobile anionic species. Mobile uranium species are contaminating the groundwater underlying these soils. The development of a site-specific remediation technology is urgently needed for the FEMP site

Distribution of natural uranium in groundwater around Kudankulam

International Nuclear Information System (INIS)

Selvi, B.S.; Vijayakumar, B.; Rana, B.K.; Ravi, P.M.

2016-01-01

A systematic study was carried out to estimate the uranium concentration in the ground water around Kudankulam in Southern Tamil Nadu. The uranium concentration in ground water varies from 0.2 to 6.6 μg/l, with a mean value of 2.0 μg/l. The Quantalase uranium analyzer was used to measure the uranium concentration. These groundwater samples were analyzed for the water quality parameters such as pH, conductance, total dissolved solids (TDS), salinity, chloride, and sulfate. An attempt has been made to correlate the uranium concentration with the water quality parameters. It is observed that conductance, TDS, salinity, chloride, and sulfate show positive correlation with uranium concentration. (author)

Uranium complex recycling method of purifying uranium liquors

International Nuclear Information System (INIS)

Elikan, L.; Lyon, W.L.; Sundar, P.S.

1976-01-01

Uranium is separated from contaminating cations in an aqueous liquor containing uranyl ions. The liquor is mixed with sufficient recycled uranium complex to raise the weight ratio of uranium to said cations preferably to at least about three. The liquor is then extracted with at least enough non-interfering, water-immiscible, organic solvent to theoretically extract about all of the uranium in the liquor. The organic solvent contains a reagent which reacts with the uranyl ions to form a complex soluble in the solvent. If the aqueous liquor is acidic, the organic solvent is then scrubbed with water. The organic solvent is stripped with a solution containing at least enough ammonium carbonate to precipitate the uranium complex. A portion of the uranium complex is recycled and the remainder can be collected and calcined to produce U 3 O 8 or UO 2

Uranium in bone: metabolic and autoradiographic studies in the rat

International Nuclear Information System (INIS)

Priest, N.D.; Haines, J.W.; Howells, G.R.; Green, D.

1982-01-01

The distribution and retention of intravenously injected hexavalent uranium-233 in the skeleton of the female rat has been investigated using a variety of autoradiographic and radiochemical techniques. These showed that approximately one third of the injected uranium is deposited in the skeleton where it is retained with an initial biological half-time of approximately 40 days. The studies also showed that: 1) Uranium is initially deposited on to all types of bone surface, but preferentially on to those that are accreting. 2) Uranium is deposited in the calcifying zones of skeletal cartilage. 3) Bone accretion results in the burial of surface deposits of uranium. 4) Bone resorption causes the removal of uranium from surfaces. 5) Resorbed uranium is not retained by osteoclasts and macrophages in the bone marrow. 6) Uranium removed from bone surfaces enters the bloodstream where most is either redeposited in bone or excreted via the kidneys. 7) The recycling of resorbed uranium within the skeleton tends to produce a uniform level of uranium contamination throughout mineralized bone. These results are taken to indicate that uranium deposition in bone shares characteristics in common with both the 'volume-seeking radionuclides' typified by the alkaline earth elements and with the 'bone surface-seeking radionuclides' typified by plutonium. (author)

Uranium in bone: metabolic and autoradiographic studies in the rat.

Science.gov (United States)

Priest, N D; Howells, G R; Green, D; Haines, J W

1982-03-01

The distribution and retention of intravenously injected hexavalent uranium-233 in the skeleton of the female rat has been investigated using a variety of autoradiographic and radiochemical techniques. These showed that approximately one third of the injected uranium is deposited in the skeleton where it is retained with an initial biological half-time of approximately 40 days. The studies also showed that: 1 Uranium is initially deposited onto all types of bone surface, but preferentially onto those that are accreting. 2 Uranium is deposited in the calcifying zones of skeletal cartilage. 3 Bone accretion results in the burial of surface deposits of uranium. 4 Bone resorption causes the removal of uranium from surfaces. 5 Resorbed uranium is not retained by osteoclasts and macrophages in the bone marrow. 6 Uranium removed from bone surfaces enters the bloodstream where most is either redeposited in bone or excreted via the kidneys. 7 The recycling of resorbed uranium within the skeleton tends to produce a uniform level of uranium contamination throughout mineralized bone. These results are taken to indicate that uranium deposition in bone shares characteristics in common with both the 'volume-seeking radionuclides' typified by the alkaline earth elements and with the 'bone surface-seeking radionuclides' typified by plutonium.

Uranium,Radium and Iron Absorption from Liquid Waste Uranium Ore Processing by Zeolite

International Nuclear Information System (INIS)

Wismawati, T; Sorot sudiro, A; Herjati, T

1998-01-01

The aim of this work is to determine zeolites sorption capacity and the distribution coefficient of uranium, radium, and iron in zeolite-liquid waste system. Mineralogical composition of zeolite used in the experiment has been determine by examining the thin sections of zeolite grains under a microscope. Zeolite has ben activated by the dilute sulfuric acid or sodium hydroxide solution. The results show that the use of 0.25 N sodium hydroxide solution could be optimizing the zeolite for uranium and iron ions sorption and that of 0.1 N sulfuric acid solution is for radium sorption. The re-activation process has been carried out in three hours. Under such a condition, the sorption efficiency of zeolite to those ions have been known to be 45.85% for uranium, 96.63 % for iron and 87.80 % for radium. The distribution coefficients of uranium, radium and iron ion in zeolite-liquid waste system have been calculated 0.85, 7.02, and 28.65 ml/g respectively

Magnetic and elastic properties of the antiferromagnet uranium mononitride

International Nuclear Information System (INIS)

Van Doorn, C.F.

1976-10-01

The magnetic and elastic properties of antiferromagnetic uranium mononitride single crystals are studied in the thesis from the measurements of the temperature dependences of the magnetic susceptibility, electrical resistivity and elastic constants. The elastic constants C 11 , C 12 and C 44 were determined in the temperature interval 4 to 300 K by ultrasonic measurements of the five possible wave velocities in the [100] and [110] directions. A test for internal consistency was also made. A dip of about 9 percent occurs in C 11 at a temperature of 5 to 6 K lower than the Neel temperature T(N) (equals about 53 K). Starting at T(N), a renormalization in C 44 is proportional to the square of the sublattice magnetization also occurs. Both these results agree with model calculations which include spin-phonon interactions. The investigation of this anomaly was extended by measuring the electrical resistivity of a sample cut from the same crystal as that on which the elasticity was measured. No anomalous behavior was observed at the temperature where C 11 displays its anomaly. However, a discontinuity in the temperature derivative of the resistance was found at T(N). The possible effect of a magnetic field on the resistivity, as well as on the elasticity, was investigated without any measurable effect. The magnetic susceptibility was measured with a Foner magnetometer between 4 and 1 000 K. It was found that above the Neel temperature the paramagnetic susceptibility followed a revised Curie-Weiss law. In an attempt to ascertain the ionic state of the 5f-uranium ion in UN, use was made of the experimentally determined Weiss constant, spin disorder resistivity and Knight shift. A calculation was made that gave a good representation of the ratio of the experimental susceptibilities along the [100] and [110] directions in the ordered region [af

Uranium content in soils, vegetables, cereals and fruits

International Nuclear Information System (INIS)

Frindik, O.

1988-01-01

As compared to other vegetable samples, parsley leaves showed a much higher uranium content, presumably due to tightly adhering dust which could not be removed by washing. Uranium transfer factors from the soil to the plants were calculated; these factors always include the total uranium concentration and not only the 'soluble' uranium. As compared to U-238 the activity of U-234 is nearly always higher in vegetable samples, but lower in soil samples. (orig./HP) [de

Uranium refining by solvent extraction

International Nuclear Information System (INIS)

Kraikaew, J.; Srinuttrakul, W.

2014-01-01

The solvent extraction process to produce higher purity uranium from yellowcake was studied in laboratory scale. Yellowcake, which the uranium purity is around 70% and the main impurity is thorium, was obtained from monazite processing pilot plant of Rare Earth Research and Development Center in Thailand. For uranium re-extraction process, the extractant chosen was Tributylphosphate (TBP) in kerosene. It was found that the optimum concentration of TBP was 10% in kerosene and the optimum nitric acid concentration in uranyl nitrate feed solution was 4 N. An increase in concentrations of uranium and thorium in feed solution resulted in a decrease in the distribution of both components in the extractant. However, the distribution of uranium into the extractant was found to be more than that of thorium. The equilibration study of the extraction system, UO_2(NO_3)/4N HNO_3 – 10%TBP/Kerosene, was also investigated. Two extraction stages were calculated graphically from 100,000 ppm uranium concentration in feed solution input with 90% extraction efficiency and the flow ratio of aqueous phase to organic phase was adjusted to 1.0. For thorium impurity scrubbing process, 10% TBP in kerosene was loaded with uranium and minor thorium from uranyl nitrate solution prepared from yellowcake and was scrubbed with different low concentration nitric acid. The results showed that at nitric acid normality was lower than 1 N, uranium distributed well to aqueous phase. As conclusion, optimum nitric acid concentration for scrubbing process should not less than 1 N and diluted nitric acid or de-ionized water should be applied to strip uranium from organic phase in the final refining process. (author)

Uranium

International Nuclear Information System (INIS)

Toens, P.D.

1981-03-01

The geological setting of uranium resources in the world can be divided in two basic categories of resources and are defined as reasonably assured resources, estimated additional resources and speculative resources. Tables are given to illustrate these definitions. The increasing world production of uranium despite the cutback in the nuclear industry and the uranium requirements of the future concluded these lecture notes

Uranium: the nuclear fuel. [Canada

Energy Technology Data Exchange (ETDEWEB)

Smith, E E.N. [Eldorado Nuclear Ltd., Ottawa, Ontario (Canada)

1976-05-01

A brief history is presented of Canadian uranium exploration, production, and sales. Statistics show that Canada is a good customer for its own uranium due to a rapidly expanding nuclear power program. Due to an average 10 year lag between commencement of exploration and production, and with current producers sold out through 1985, it is imperative that exploration efforts be increased.

Sorption of uranium by cellulose derivatives

International Nuclear Information System (INIS)

Muroi, M.; Imai, S.; Hamaguchi, A.

1985-01-01

The sorption behaviour of uranium was investigated by batch and column methods using four cellulose derivatives, two having an amino group and two having an amino group plus a dithiocarboxylate group. All four derivatives showed maximum uranium sorption from pure water in the neutral region or from artificial sea water in the acidic region. In the batch method, quantitative removal of 100 μg of uranium from 50 ml of water at pH 5.0 was achieved by equilibration with 50 mg of any of the four sorbents. The percentage removal under these conditions decreased gradually with increasing concentration of uranium above 100 μg per 50 ml. A similar high percentage removal of uranium was achieved using artificial sea water. In the column method, quantitative removal of 5 μg of uranium from 1l of water at pH 6.7 was achieved with 200 mg of either of the two sorbents. Similar quantitative removal of uranium was achieved from 1l of artificial sea water at pH 5.4 with 500 mg of either of the two sorbents. (author)

A DBN based anomaly targets detector for HSI

Science.gov (United States)

Ma, Ning; Wang, Shaojun; Yu, Jinxiang; Peng, Yu

2017-10-01

Due to the assumption that Hyperspectral image (HSI) should conform to Gaussian distribution, traditional Mahalanobis distance-based anomaly targets detectors perform poor because the assumption may not always hold. In order to solve those problems, a deep learning based detector, Deep Belief Network(DBN) anomaly detector(DBN-AD), was proposed to fit the unknown distribution of HSI by energy modeling, the reconstruction errors of this encode-decode processing are used for discriminating the anomaly targets. Experiments are implemented on real and synthesized HSI dataset which collection by Airborne Visible Infra-Red Imaging Spectrometer (AVIRIS). Comparing to classic anomaly detector, the proposed method shows better performance, it performs about 0.17 higher in Area Under ROC Curve (AUC) than that of Reed-Xiaoli detector(RXD) and Kernel-RXD (K-RXD).

Quantum machine learning for quantum anomaly detection

Science.gov (United States)

Liu, Nana; Rebentrost, Patrick

2018-04-01

Anomaly detection is used for identifying data that deviate from "normal" data patterns. Its usage on classical data finds diverse applications in many important areas such as finance, fraud detection, medical diagnoses, data cleaning, and surveillance. With the advent of quantum technologies, anomaly detection of quantum data, in the form of quantum states, may become an important component of quantum applications. Machine-learning algorithms are playing pivotal roles in anomaly detection using classical data. Two widely used algorithms are the kernel principal component analysis and the one-class support vector machine. We find corresponding quantum algorithms to detect anomalies in quantum states. We show that these two quantum algorithms can be performed using resources that are logarithmic in the dimensionality of quantum states. For pure quantum states, these resources can also be logarithmic in the number of quantum states used for training the machine-learning algorithm. This makes these algorithms potentially applicable to big quantum data applications.

Recovery of uranium from uranium bearing black shale

International Nuclear Information System (INIS)

Das, Amrita; Yadav, Manoj; Singh, Ajay K.

2016-01-01

Black shale is the unconventional resource of uranium. Recovery of uranium from black shale has been carried out by the following steps: i) size reduction, ii) leaching of uranium in the aqueous medium, iii) fluoride ion removal, iv) solvent extraction of uranium from the aqueous leach solution, v) scrubbing of the loaded solvent after extraction to remove impurities as much as possible and vi) stripping of uranium from the loaded organic into the aqueous phase. Leaching of black shale has been carried out in hydrochloric acid. Free acidity of the leach solution has been determined by potentiometric titration method. Removal of fluoride ions has been done using sodium chloride. Solvent extraction has been carried out by both tributyl phosphate and alamine-336 as extractants. Scrubbing has been tried with oxalic acid and sulphuric acid. Stripping with sodium carbonate solution has been carried out. Overall recovery of uranium is 95%. (author)

Uranium resources, 1983

International Nuclear Information System (INIS)

1983-01-01

The specific character of uranium as energy resources, the history of development of uranium resources, the production and reserve of uranium in the world, the prospect regarding the demand and supply of uranium, Japanese activity of exploring uranium resources in foreign countries and the state of development of uranium resources in various countries are reported. The formation of uranium deposits, the classification of uranium deposits and the reserve quantity of each type are described. As the geological environment of uranium deposits, there are six types, that is, quartz medium gravel conglomerate deposit, the deposit related to the unconformity in Proterozoic era, the dissemination type magma deposit, pegmatite deposit and contact deposit in igneaus rocks and metamorphic rocks, vein deposit, sandstone type deposit and the other types of deposit. The main features of respective types are explained. The most important uranium resources in Japan are those in the Tertiary formations, and most of the found reserve belongs to this type. The geological features, the state of yield and the scale of the deposits in Ningyotoge, Tono and Kanmon Mesozoic formation are reported. Uranium minerals, the promising districts in the world, and the matters related to the exploration and mining of uranium are described. (Kako, I.)

Uranium management activities

International Nuclear Information System (INIS)

Jackson, D.; Marshall, E.; Sideris, T.; Vasa-Sideris, S.

2001-01-01

One of the missions of the Department of Energy's (DOE) Oak Ridge Office (ORO) has been the management of the Department's uranium materials. This mission has been accomplished through successful integration of ORO's uranium activities with the rest of the DOE complex. Beginning in the 1980's, several of the facilities in that complex have been shut down and are in the decommissioning process. With the end of the Cold War, the shutdown of many other facilities is planned. As a result, inventories of uranium need to be removed from the Department facilities. These inventories include highly enriched uranium (HEU), low enriched uranium (LEU), normal uranium (NU), and depleted uranium (DU). The uranium materials exist in different chemical forms, including metals, oxides, solutions, and gases. Much of the uranium in these inventories is not needed to support national priorities and programs. (author)

Thermodynamic properties of α-uranium

International Nuclear Information System (INIS)

Ren, Zhiyong; Wu, Jun; Ma, Rong; Hu, Guichao; Luo, Chao

2016-01-01

The lattice constants and equilibrium atomic volume of α-uranium were calculated by Density Functional Theory (DFT). The first principles calculation results of the lattice for α-uranium are in agreement with the experimental results well. The thermodynamic properties of α-uranium from 0 to 900 K and 0–100 GPa were calculated with the quasi-harmonic Debye model. Volume, bulk modulus, entropy, Debye temperature, thermal expansion coefficient and the heat capacity of α-uranium were calculated. The calculated results show that the bulk modulus and Debye temperature increase with the increasing pressure at a given temperature while decreasing with the increasing temperature at a given pressure. Volume, entropy, thermal expansion coefficient and the heat capacity decrease with the increasing pressure while increasing with the increasing temperature. The theoretical results of entropy, Debye temperature, thermal expansion coefficient and the heat capacity show good agreement with the general trends of the experimental values. The constant-volume heat capacity shows typical Debye T"3 power-law behavior at low temperature limit and approaches to the classical asymptotic Dulong-Petit limit at high temperature limit. - Highlights: • Thermodynamic properties of α-U were predicted systematically with quasi-harmonic Debye model. • Summarizations of the corresponding experimental and theoretical results have been made for the EOS and other thermodynamic parameters. • The calculated thermodynamic properties show good agreement with the experimental results in general trends.