Discovery Of Uranium Research Articles

Uranium deposits of Mongolia, their exploration and mine development

Most of the known uranium deposits in Mongolia are related to volcano-tectonic structures of the Late Mesozoic and permeable sandstone aquifers of terrigenous sedimentary rocks in Late Mesozoic-Cenozoic basins. A young uranium deposit has been recently discovered at the surface in Quaternary alluvial sediments. Uranium deposits are classified here according to the International Atomic Energy Agency (IAEA) classification scheme. Beside of supergene and hydrothermal uranium discoveries, uranium mineralization can also be found in the Lower Cretaceous lignite seams, in Mesozoic alkaline intrusive rock related REE, Th, U enriched mineral systems and in metasomatic rocks, as well as in migmatites and pegmatites localized in Precambrian metamorphic rocks. Currently, no uranium can be produced in Mongolian facilities except pilot testing being done first. A pilot test was carried out at the Khairhan and Kharaat deposits in Mongolia and these experiments have demonstrated the ore to be amenable to acid leach (sulphuric acid) with the addition of an oxidizing agent. These tests confirmed that hydraulic control can be maintained and that the uranium solubilization and mobilization can be controlled. The results of the test were encouraging, with the well production rate, uranium concentration in produced solutions, chemical usage, and estimated uranium recovery all within ranges expected for normal commercial operations. There are a number of Mongolian uranium deposits are in the stage of mine development. The Government of Mongolia has approved the agreement of mine development of the Zuuvch ovoo and Dulaan uul deposits. Pilot testing on these deposits is underway and uranium will be extracted by in-situ leaching soon.

Uranium mining and sense of community in the Great Karoo: Insights from local narratives

Since the discovery of uranium in commercial quantities in the Great Karoo, plans have been in place to carry out large-scale uranium mining in the region. One of the justifications for doing so is the belief that it will catalyze socio-economic development in the region. However, some stakeholders have maintained that the proposed mining operations would threaten the social fabric of the communities in the Great Karoo region where the proposed mining operations will take place. The aim of this study is to broaden understanding of the likely impacts of the proposed mining activities on the social fabric of the surrounding communities in Beaufort West. Drawing on findgins from qualitative research, the study concludes that while the proposed mining will indeed alter the existing social fabric, it will also facilitate the human diversity required for addressing some of the developmental challenges the region faces

English

The paper presents a summary of mineral resources available in the newly formed Telangana state and associated aspects for socio-economic development of the State in time to come. The region was not given much attention in past decades for large scale exploration though it has rich mineral wealth and production is present is limited to coal, limestone, dolomites, quartz, feldspar and building stones. The hidden mineral wealth requires systematic investigations to obtain reliable data on uniform pattern for making policy and plans, through professional agencies in terms of terrain consideration, quantity and quality assessment of the mineral deposits; exploration techniques and its environmental impact assessment; policy and legal framework etc. The recent discovery of uranium is economically very promising which can be utilised for electric power generation. There is a substantial scope for other premier minerals like zinc, base metal sulphides, and platinoid group in the State. The coal deposits need to be further investigated for CBM and gasification. Investigations are vital to discover new deposits in Telangana with existing mineral occurrences as path finders, in light of modern technology. It is suggested to set up mineral based industries/plants, such as fertilizer, cement and calcium carbide, coking plants, refractory and abrasive units and cutting and polishing units for state’s socio-economic growth.

Origin of uranium deposits revealed by their rare earth element signature

Terra Nova, 23, 264–269, 2011AbstractUranium deposits form in a wide range of geological settings, including deep magmatic to surficial conditions, and range in age from Archaean to recent. These temporal and spatial variations have given rise to an extreme diversity of ore deposits. However, understanding their conditions of formation has remained challenging. This article reports rare earth element (REE) abundances, measured by microbeam methods in uranium oxides, for a series of worldwide uranium occurrences. The REE patterns are very specific to each deposit type and directly reflect the conditions of their genesis. We propose an evaluation of the first‐order parameters controlling the REE behaviour in each mineralised system. This study demonstrates that the REE pattern is the most efficient tool for constraining the geological models of uranium deposits and for genetically discriminating new uranium discoveries. This approach may form the starting point for a new procedure in the fight against nuclear trafficking.Terra Nova, 00, 1–6, 2011

Bragg, Mawson and Brown, and the Early Uranium Discoveries in South Australia

The discovery of uranium at Radium Hill in the Olary region in 1906 excited much public interest in South Australia as well as the attention of three of its most prominent scientists: W.H. Bragg, D. Mawson and H.Y.L. Brown. At the same time, radioactivity was recognised in the Moonta mines. The reaction of each was different with Bragg being revealed as more of a pure (rather than applied) scientist who was held in the highest public esteem, whilst Mawson quickly became the entrepreneur. Brown shows himself as the trustworthy, yet cautious, Government advisor. As the youngest of the three, Mawson continued his pioneering interest for the rest of his life. With the discovery of uranium at Mount Painter in 1910, his entrepreneurial acumen was enhanced, supported not only by intensive geological investigations, but also by skills in accessing the resource, sourcing development capital and envisaging mining development. His rising status as a heroic Antarctic explorer was presumably an advantage. Reduced Government and public interest in the Mount Painter discovery initially is reflected by delayed involvement from Brown, who was then approaching retirement. In 1909, Bragg left South Australia to pursue his academic career and further scientific research on radioactivity and X rays in the United Kingdom. This led to the award of the Nobel Prize in 1915 (jointly with his son), yet no ongoing involvement in South Australian uranium.

A progressive geophysical exploration strategy at the Shea Creek uranium deposit

The Athabasca Basin is a large Paleo- to Mesoproterozoic quartz arenite sandstone basin that occupies most of the northernmost quarter of Sas-katchewan and a smaller portion of northeastern Alberta. The locations of the basin and the uranium discoveries discussed in this paper are shown in Figure 1. The majority of the unconformity-type uranium deposits of the Athabasca Basin are sandstone-hosted and are associated with post-Hudsonian, reactivated graphitic faults within Aphebian metasedimentary gneisses of the Wollaston Domain and the Wollaston-Mudjatik transition zone in the eastern portion of the Athabasca Basin. However, the Shea Creek deposit, consisting of the Anne, Kianna, and Colette zones, occurs in the western portion of the basin and is associated with the transition between the granitic Clearwater Domain and the Lloyd Domain.

The search for uranium in ‘nuclear‐free’ New Zealand: Prospecting on the West Coast, 1940s to 1970s

Abstract: In a government search for uranium in 1944–1946, uneconomic deposits of radioactive minerals were found concentrated in dredge tailings on the West Coast. In 1954 a new search was initiated, leading to the 1955 discovery of uranium in the Buller Gorge. In the 25‐year investigation programme that followed, prospectors were assisted by staff from the Mines Department and the Geological Survey and were funded by grants from the New Zealand and UK governments. The prospecting continued unchallenged by the media or peace or environmental movements until 1979 when it ended for economic rather than philosophical reasons.

Uranium ores and depleted uranium in the environment, with a reference to uranium in the biosphere from the Erzgebirge/Sachsen, Germany

The Erzgebirge (‘Ore Mountains’) area in the eastern part of Germany was a major source of uranium for Soviet nuclear programs between 1945 and 1989. During this time, the former German Democratic Republic became the third largest uranium producer in the world. The high abundance of uranium in the geological formations of the Erzgebirge are mirrored in the discovery of uranium by M. Klaproth close to Freiberg City in 1789 and the description of the so-called ‘Schneeberg’ disease, lung cancer caused in miners by the accumulation of the uranium decay product, radon, in the subsurfaces of shafts. Since 1991, remediation and mitigation of uranium at production facilities, rock piles and mill tailings has taken place. In parallel, efforts were initiated to assess the likely adverse effects of uranium mining to humans. The costs of these activities amount to about 6.5 10 9 Euro. A comparison with concentrations of depleted uranium at certain sites is given.

Getting the Most Out of Radon Geochemistry: ABSTRACT

Radon and radium are specific indicators of uranium. Radon in particular is easily analyzed in the field or in a portable lab. For this reason and because of its mobility as a soluble noble gas, radon has received considerable attention in exploration. The mobility of radon is complicated by its short half-life (3.8 days) and by movements of earlier members of the decay series. Claims of the successful application of radon geochemistry to detect uranium deposits beneath several tens of meters of cover (including shale and coal beds) seem extravagant but may warrant further study. In areas of shallow overburden, radon in soil gas can extend evaluation to depths beyond reach of the scintillometer. Radon to thoron ratios are useful in this work as well as radon content itself. Day-to-day variations of radon content in soil gas are confusing, but seldom obscure trends and anomalies. Lake-water radon anomalies are associated with two recent major uranium discoveries in the Canadian Shield. In both discoveries, the radon anomalies were detected in the earliest stages of exploration in the area. Radium, the parent of radon, also can be readily determined in a portable laboratory. In an example from southeast Texas, a dramatic reduction in radium values has been measured in groundwater within a few hundred feet of an orebody. Anomalous radium measurements other than those associated with uranium mineralization or geothermal waters are extremely rare. End_of_Article - Last_Page 754------------

Major Uranium Discovery in Volcaniclastic Sediments, Basin and Range Province, Yavapai County, Arizona

The Anderson Mine uranium deposit in west-central Arizona is one of the first significant uranium discoveries in the Basin and Range province. The deposit occurs in gently dipping Miocene lacustrine sediments near the northeastern margin of the Date Creek basin. Mineralized units are primarily carbonaceous mudstones and siltstones interbedded with fine tuffaceous sedimentary rocks, freshwater marlstones and limestones, and a few thin sandstones. The sequence is underlain by Eocene(?) andesitic volcanic rocks and overlain by Miocene sedimentary rocks and basalt. The uranium deposit has a tabular or blanket-type configuration with minimum dimensions of approximately 1,000 by 1,500 m. Mineralization extends at least 1,000 m farther downdip to the south. The mineralized zone is composed of several beds that are generally 1 to 3 m thick, but range up to 11 m. The mineralization is stacked in most areas and aggregate thicknesses greater than 15 m are common. Mineral grades range from 0.03 to 0.10% U3O8, with an average grade of approximately 0.07%. Molybdenum, sulfur, vanadium, and organic carbon are concentrated with the uranium mineralization. Other elements which are anomalous in much of the Anderson Mine strata include manganese, lithium, and fluorine. In parts of the orebody, there are variations in the disequilibrium fa tor; however, the overall factor is approximately 1.00. The uranium-bearing tuffaceous sediments were deposited during periods of felsic volcanism in sheltered backwater areas marginal to an expanding Miocene lake. During subsequent compaction and dewatering of these uranium-rich lake sediments, the expelled alkaline fluids came in contact with strongly reducing paludal sediments causing the precipitation and fixation of uranium. Associated zeolitization, silicification, and argillic alteration indicate an early diagenetic origin for the primary coffinite(?) mineralization. Some remobilization and precipitation of uranium minerals in fractures have occurred in recent geologic time.

Exploration and Development of Uranium Reserves: ABSTRACT

Nuclear fuel consumption in the United States is dependent on the demand for electrical energy. Domestic electric-power-generating capacity is growing at an annual rate of 7-8%. The nuclear power growth rate will be substantially higher if nuclear energy is to become the major fuel source for electric power generation by the end of this century. Proved and potential domestic uranium reserves are sufficient to fill the anticipated demand for nuclear fuel through 1980. Beyond that point new reserves must be brought into production at an increasing rate, with new reserves of 175,000 tons required for the period from 1981-1985. New production facilities for these reserves must be committed beginning in 1976. The first discoveries of new uranium reserves in the United States must be made in 1972, and the entire 175,000 tons should be proved before the end of the decade. The cost of exploration to assure the new reserves required in the 1981-1985 period is estimated to be $315 million or about $79 million annually. This is in addition to the expenditures required to bring over 100,000 tons, now carried as potential reserves, into the proved category. The problem now facing the domestic uranium industry is how to meet the demands of the late 1970s and 1980s through investments which must be made today. The large expenditures required for exploration and expanded production capacity cannot be made from current below-replacement-cost uranium sales. The reserves required to support the needed expansion of the nuclear power industry will be assured when there is sufficient incentive established through long-term purchase agreements at realistic prices. The annual discovery requirement needed for a 10-year forward reserve quickly reaches 100,000 tons/year beyond 1980. This means that a district equivalent in size to Ambrosia Lake, New Mexico, the largest in the United States, must be discovered every other year. Far more exploration than presently is contemplated must be performed in the vicinity of established districts and increased emphasis must be placed on the discovery of uranium in environments not presently recognized. Large sums of money for exploration must be committed End_Page 606------------------------------ in the near future to meet the demands of the nuclear power industry. End_of_Article - Last_Page 607------------

Integrated Exploration Economics in Wyoming: Viewpoint of Geologist: ABSTRACT

Wyoming's general economy is dependent on its exploration geologists and the half-billion-dollar productivity of its minerals industry. Extraordinary uranium discoveries in sedimentary rocks, broad-scale leasing for coal, and an abnormally high, record-setting, wildcat success ratio of 10:1 in the petroleum industry have been contributing factors. Integration of mining and petroleum activities in Wyoming have prompted modifications in exploration programs and resulted in improved evaluation techniques. Increased intercompany communication and improved industrial-related services have helped to broaden the economic perspective. Although economics continues to influence the ebb and flow of exploration at the individual company level, it plays only a subordinate role in the overall statewide picture. Geologic prospects rejected by 1 company as not economic are quickly absorbed by another. Marginal prospects have become successful ventures End_Page 860------------------------------ because of flexibility and concessions on the part of management. Companies with stereotyped exploration policies regarding fixed ROI formulas, minimum size of land holdings, exploration procedures, and partnership arrangements, find it difficult to compete. Examples of exploration geologists' influence on corporate decisions show how the merits of a prospect can change. They illustrate the disadvantages of restricting the geologist prematurely with economic limitations and suggest that the premonitions and innermost thoughts of the explorer should be included in geologic reports. There seems to be no substitute for exploration experience in dealing with important but intangible parameters. End_of_Article - Last_Page 861------------

Stratigraphy of Jackson Group (Eocene), South-Central Texas

Discovery of uranium and renewed exploratory activity for oil and gas in the outcrop area of the Jackson group of Eocene age in south-central Texas require setting up a standard nomenclature for rocks of the group in that area. In general, the names which Ellisor proposed in 1933 have been used, but modified to agree with current usage by most geologists. The Jackson group, as proposed, consists of four formations, in descending order: Whitsett, McElroy, Wellborn sandstone, and Caddell. The Whitsett formation, comprising the Fashing clay, Calliham sandstone, Dubose, and Stones Switch sandstone members, consists chiefly of bentonitic clays and tuff near the top and sandstones near the base. The McElroy formation consists of the Conquista clay (a new name substituted for the pre-empted name Falls City shale of Ellisor, 1933), the Dilworth sandstone, and the Manning clay members. The Wellborn sandstone and the clayey Caddell formation are indivisible into members in south-central Texas.

Geology of the Dakota Formation uraninite deposit near Morrison, Colorado

Several significant uranium discoveries have been made since 1953 along the front range of Colorado. Uranium ore has been found both in Precambrian rocks and sedimentary rocks. The Precambrian rocks consist of metasediments and intrusive batholithic granites. The sediments range from Pennsylvanian to Tertiary in age. Uranium ore is found in the upper (Muddy) sandstone member of the Dakota formation in close association with asphalt, pyrite, and ilsmenite (molybdenum oxide) and is controlled by a west dipping strike-slip fault. The ore body occupies a position adjacent to and in the footwall side of the fault, and traces of uranium are found on the hanging wall side. Uranium is also found in the lower sandy portion of the Dakota shale.The uraninite is believed to be a primary ore of hydrothermal origin. It is further suggested that uranium-bearing hydrothermal solutions originated in the Precambrian complex and migrated eastward along the Golden thrust fault. The Golden thrust fault, which underlies the area, therefore served as a conduit for the solutions. The solutions then migrated into minor shear zones that intersect the main Golden thrust fault, and where these minor faults traversed permeable sandstone, the solutions impregnated the sandstone. Uranium was then precipitated from the hydrothermal solutions when favorable conditions for deposition, such as asphaltum, were encountered.