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Over a period of some 100 years it has gradually been accepted that the human skeletal remains found in the late nineteenth century in ancient gravels at Galley Hill, Kent are not those of early man, but are of much more recent date. This conclusion was finally verified by means of relative (N, F) and absolute (14C) dating. Here we present the results of further analysis of the remains from Galley Hill for their uranium content by a method having general application to the relative dating of fossil human and other mammalian bone.  相似文献   
2.
Drawing together insights from neo‐Innisian geography and environmental history, this paper explores the landscape and environmental changes engendered by ‘cyclonic’ patterns of development associated with uranium production at Uranium City, Saskatchewan. Strong postwar demand for uranium led to the establishment and rapid expansion of Uranium City on the north shore of Lake Athabasca as a ‘yellowcake town’, dedicated to producing uranium oxide concentrate to supply federal government contracts with the US military. In spite of optimistic assessments for the region's industrial future, the new settlement remained inherently unstable, tied to shifting institutional arrangements and external markets, and haunted by the spectre of resource depletion. The planning and development of the townsite at Uranium City reflected both neocolonial desires to open the north to Euro‐Canadian settlement and efforts by the state to buffer the stormy effects of resource dependency. Ultimately, however, quixotic government efforts to implant an outpost of industrial modernity in the Athabasca Region failed to forestall the inevitable winds of change, which left in their wake destructive legacies of social dislocation and environmental degradation, already evident with the near‐collapse of the uranium export market by the early 1960s.  相似文献   
3.
In June 1975, Helmut Schmidt's government in West Germany sanctioned the sale of a complete nuclear fuel cycle to Brazil, including uranium enrichment and reprocessing technology. US observers in Congress, government, and the media reacted with alarm to this apparent setback to global non-proliferation efforts as spearheaded by the Nuclear Suppliers Group. Using material from US, British, and German archives, this article examines how structural disparities in the US-German relationship augmented mutual suspicions and led both parties to behave uncooperatively.

Focused narrowly on commercial rivalry with the US, politicians and industry representatives in Bonn brushed aside the concerns of non-proliferation experts, who had a weak institutional base. Jimmy Carter came to office in 1977 determined to block the consummation of the Brazil deal; he also pressed the G-7 to discontinue nuclear fuel reprocessing. Carter's abrupt unilateralism offended US allies, but together the US and France put pressure on West Germany to renounce sensitive nuclear exports. Schmidt grudgingly agreed to show more caution, but few lessons were learned; many Germans came away feeling that US-led export restrictions were overbearing, hypocritical and self-serving. While cooperative within NATO and European frameworks, West Germans remained ambivalent on global problems of proliferation until the 1990s.  相似文献   
4.
This article examines the role played by gendered constructions and categories in Canadian cold war appropriations of Aboriginal lands for nuclear production. Focusing primarily on the ways in which gendered tropes were mobilized by wives and companions of uranium workers recently arrived in the Serpent River watershed (home of the Serpent River Anishinabe) at the end of the first global uranium boom in which uranium production in the watershed was severely threatened, I explore how gendered constructions and categories provided important cartographies and reference points with which to order and maintain possession of the lands of the Serpent River watershed as a singular, Canadian, nuclear space. Drawing on Kaika's (2004) work on the discursive production of ‘home’, I argue that representations of the watershed as home in the wilderness and as imperilled domestic space, as well as the important ways in which they worked to secure discursive rights to space within the broader registers of white Canadian post war gender difference, relied on the near-complete erasure of Aboriginal presence and culture from the land for continuity. I conclude that while this erasure facilitated (morally and practically) the further incorporation of the watershed into Canadian geographies of nuclear production, it also worked to obscure the ways in which the industry and uranium economy were able to capitalize on Aboriginal lands, labour and their subordinate position in Canadian society.  相似文献   
5.
Uranium/thorium (U/Th)‐rich bitumen has been discovered within both Palaeoproterozoic black pelites and the Archean granitic basement of the Rum Jungle Mineral Field, Northern Territory, Australia. Granite‐hosted bitumen occurs as small (up to 400‐µm diameter) discrete individual nodules, which exhibit many morphological similarities to those observed in Phanerozoic siliciclastic rocks. Thorium, the dominant radioelement, occurs primarily as a hydrated Th–Y–Si–P phase. Uranium‐rich inclusions are rare, and correspond to a hydrated U–Th–Y–Si–P phase, identified as coffinite–thorogummite. Metasediment‐hosted bitumen is more variable in morphology, occurring as massive (<2 cm in width) veins that cross‐cut all foliations, as discrete individual nodules or as elongate seams (up to 500 µm in length), interpreted to represent a series of coalesced individual nodules. In all examples, uranium, the dominant radioelement in the metasediment‐hosted bitumen, is present as Th‐poor uraninite, with variable Y2O3 contents (up to 3.21 wt.%). Raman investigation of all types of bitumen indicates that it is a poorly organized carbonaceous matter, which has not been subjected to metamorphism. Consequently, a post‐metamorphic timing for hydrocarbon emplacement can be inferred and a magmatic origin can be precluded. Potential source rocks for the bitumen are black shales of the Whites Formation (up to 8 wt.% total organic carbon (TOC)) and the Koolpin Formation (approximately 13 wt.% TOC). Post‐metamorphic sericitization of rocks within the Whites Formation is accompanied by a near‐complete removal of organic matter. Alteration was possibly the catalyst for hydrocarbon generation. The Th–Y–Si–P phase within the granite‐hosted nodules is interpreted to be the result of the alteration of antecedent monazite. During this alteration, U, LREE and P were fractionated and removed, while Th, Y and Si remained immobile, and recombined to form a hydrated Th–Y–Si phase. This pervasive alteration within the basement U/Th‐rich granites is proposed as a genetic model for the formation of uranium deposits in the Rum Jungle Mineral Field and possibly unconformity associated uranium deposits on a global scale.  相似文献   
6.
The Dongsheng uranium deposit, the largest in situ leach uranium mine in the Ordos Basin, geometrically forms a roll‐front type deposit that is hosted in the Middle Jurassic Zhiluo Formation. The genesis of the mineralization, however, has long been a topic of great debate. Regional faults, epigenetic alterations in surface outcrops, natural oil seeps, and experimental findings support a reducing microenvironment during ore genesis. The bulk of the mineralization is coffinite. Based on thin‐section petrography, some of the coffinite is intimately intergrown with authigenic pyrite (ore‐stage pyrite) and is commonly juxtaposed with some late diagenetic sparry calcite (ore‐stage calcite) in primary pores, suggesting simultaneous precipitation. Measured homogenization temperatures of greater than 100°C from fluid inclusions indicate circulation of low‐temperature hydrothermal fluids in the ore zone. The carbon isotopic compositions of late calcite cement (δ13CVPDB = ?31.0 to ?1.4‰) suggest that they were partly derived from sedimentary organic carbon, possibly from deep‐seated petroleum fluids emanating from nearby faults. Hydrogen and oxygen isotope data from kaolinite cement (δD = ?133 to ?116‰ and δ18OSMOW = 12.6–13.8‰) indicate that the mineralizing fluids differed from magmatic and metamorphic fluids and were more depleted in D (2H) than modern regional meteoric waters. Such a strongly negative hydrogen isotopic signature suggests that there has been selective modification of δD by CH4±H2S±H2 fluids. Ore‐stage pyrite lies within a very wide range of δ34S (?39.2 to 26.9‰), suggesting that the pyrite has a complex origin and that bacterially mediated sulfate reduction cannot be precluded. Hydrocarbon migration and its role in uranium reduction and precipitation have here been unequivocally defined. Thus, a unifying model for uranium mineralization can be established: Early coupled bacterial uranium mineralization and hydrocarbon oxidation were followed by later recrystallization of ore phases in association with low‐temperature hydrothermal solutions under hydrocarbon‐induced reducing conditions.  相似文献   
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8.
World‐class unconformity‐related U deposits in the Athabasca Basin (Saskatchewan, Canada) are generally located within or near fault zones that intersect the unconformity between the Athabasca Group sedimentary basin rocks and underlying metamorphic basement rocks. Two distinct subtypes of unconformity‐related uranium deposits have been identified: those hosted primarily in the Athabasca Group sandstones (sediment‐hosted) and those hosted primarily in the underlying basement rocks (basement‐hosted). Although significant research on these deposits has been carried out, certain aspects of their formation are still under discussion, one of the main issues being the fluid flow mechanisms responsible for uranium mineralization. The intriguing feature of this problem is that sediment‐hosted and basement‐hosted deposits are characterized by oppositely directed vectors of fluid flow via associated fault zones. Sediment‐hosted deposits formed via upward flow of basement fluids, basement‐hosted deposits via downward flow of basinal fluids. We have hypothesized that such flow patterns are indicative of the fluid flow self‐organization in fault‐bounded thermal convection (Transport in Porous Media, 110, 2015, 25). To explore this hypothesis, we constructed a simplified hydrogeologic model with fault‐bounded thermal convection of fluids in the faulted basement linked with fluid circulation in the overlying fault‐free sandstone horizon. Based on this model, a series of numerical experiments was carried out to simulate the hypothesized fluid flow patterns. The results obtained are in reasonable agreement with the concept of fault‐bounded convection cells as an explanation of focused upflow and downflow across the basement/sandstone unconformity. We then discuss application of the model to another debated problem, the uranium source for the ore‐forming basinal brines.  相似文献   
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