砂岩型铀矿床中SiO2/Al2O3比值与含矿性的关系研究:以库捷尔太和乌库尔其铀矿床为例

对库捷尔太和乌库尔其铀矿床进行了详细的层间氧化带的分带研究,在此基础上分析了主要元素Si,Al,Fe在层间氧化带各亚带中的迁移规律。研究表明,被认为稳定元素的So,Al在砂岩层间氧化过程中具有明显的变化规律：Si在氧化带具迁出特征,并随氧化作用的减弱而迁出的份额有规律的减少;而Al的地球化学行为则相反。不同的SiO2／Al2O3比值能够反映层问氧化带的含矿性。     

REE/trace element characteristics of sandstone-type uranium deposits in the Ordos Basin

1 Introduction The Ordos Basin is the second largest sedimentary basin in China. During the last 10 years, a great progress has been achieved in the aspects of tectonic evolution, dynamics process, inner and outer geological processes during Mesozoic-Cen…     

某花岗岩型铀矿田断裂构造的分形特征

基于分形理论,提出了一种快速测量多区断裂分维值的方法,并获得了研究区断裂分维值的平面等值图。研究结果表明,断裂分维值的大小较好地反映了断裂构造复杂程度的高低,它们之间存在着正相关关系。研究区花岗岩型铀矿田内约有86%的铀矿床位于断裂分维值D偏高(D>1.18)的区域内,表明断裂分维值越大,越有利于花岗岩型铀矿成矿,为建立该区花岗岩型铀矿新的预测标志提供了参考依据。     

浙西北火山岩型铀矿床的成矿条件及成矿规律研究

本文根据广泛的野外调查研究和大量的分析统计数据,讨论了浙西北火山岩型铀矿床形成的地质条件和物理化学条件。重点探讨了劳村组、黄尖组和寿昌组的含铀性及岩性、岩相、构造和岩浆活动对成矿的控制作用。探讨了成矿溶液的成分、性质、温度和铀的迁移形式,以及成矿物质来源和成矿机理,并在此基础上总结出铀成矿的时空规律。     

世界核电发展及铀供需态势展望

以权威机构发布的最新资料数据为基础,介绍了世界核电近期至中长期的发展态势,归纳了当前世界铀生产的主要特点,初步分析了至2030年铀的供需关系。认为从世界层面看,铀资源对于近期和中长期的世界铀生产和核电铀需求是有充分保障的,世界铀生产可以满足近期的核电铀需求,但至2015年以后核电的快速发展时期又会出现较大的供需缺口。如果世界新铀矿山的投产和老铀矿山的扩产计划都能如期悉数实现,铀生产满足长期核电铀需求是完全可能的。     

松辽盆地东北缘白垩系砂岩型铀矿成矿条件与找矿方向

通过松辽盆地东北缘蚀源区铀源条件、中生代构造演化、白垩系沉积建造研究,结合石油部门地震连井剖面等资料,综合分析了松辽盆地东北部砂岩型铀矿的成矿条件研究,认为盆缘的富铀花岗岩体提供了丰富的铀源,中生代后期反转构造形成的剥蚀天窗为含铀含氧水的渗入渗出提供了通道.研究结果显示,松辽盆地东北部绥棱地区为最有利的砂岩型铀矿找矿部位,主要找矿目标层为上白垩统泉头组兼顾浅部姚家组,找矿类型为层间氧化带型.     

大坪里—向阳坪地区铀成矿条件分析

从岩体特征、构造条件、围岩蚀变,以及矿石类型等方面总结了大坪里—向阳坪地区铀成矿特征,开展了铀成矿条件分析。并与沙子江铀矿床铀成矿特征相比较,确定找矿类型为受脆-韧性走滑断裂带控制的硅质脉型热液铀矿,为今后的工作奠定了基础。     

秦岭主峰太白山北麓降水化学特征分析

利用太白山北麓2011年12月-2013年7月共39次降水样品数据资料, 定量分析了该区域降水化学的特征和时间变化规律. 结果表明: 太白山北麓地区降水中, 除常量离子Na⁺、NH₄⁺、K⁺、Mg²⁺、Ca²⁺、F^-、Cl^-、SO₄^2-、NO₃^-外, CO₃^2-、HCO₃^-、PO₄^3-及低分子有机酸也占有相当比例. 研究区降水常量离子浓度的顺序依次为: NH₄⁺ > SO₄^2- > Ca²⁺ > NO₃^- > Na⁺ > Cl^- > Mg²⁺ > K⁺ > F^-, 离子总浓度表现出明显的季节变化: 夏季(轻度污染) < 秋季(中等污染) < 春季(严重污染) < 冬季(极重污染). 利用因子分析法得出太白山北麓地区降水组分主要有三种来源; Na⁺、Cl^-、Mg²⁺、Ca²⁺主要来自地壳源, SO₄^2-、NO₃^-、NH₄⁺主要来自人为源, K⁺和F^-主要由海盐源和人为源共同贡献. 根据Hysplit 后向气流轨迹分析, 得出不同路径气团降水离子组分不同: 受地形等因素影响, 北方路径的气团比南方路径气团离子总浓度较高; 受土壤类型影响, 西北方向气团降水Na⁺、Mg²⁺、Ca²⁺浓度较高; 受人为活动影响, 东北方向SO₄^2-、NO₃^-、NH₄⁺浓度较高.     

The composition of nutrient fluxes from contrasting UK river basins

Accurate estimates of N and P loads were obtained for four contrasting UK river basins over a complete annual cycle. The fractionation of these loads into dissolved and particulate, and inorganic and organic components allowed a detailed examination of the nutrient load composition and of the factors influencing both the relative and absolute magnitude of these components. The particulate phosphorus (TPP) loads account for 26–75% of the annual total phosphorus (TP) transport and are predominantly inorganic. The inorganic (PIP) and organic (POP) fractions of the TPP loads represent 20–47% and 6–28% of the annual TP transport, respectively. In contrast, the particulate nitrogen loads (TPN) represent 8% or less of the annual total nitrogen (TN) loads and are predominately organic. For dissolved P transport, the dissolved inorganic fraction (DIP) is more important, representing 15–70% of the TP loads, whereas the dissolved organic fraction (DOP) represents only 3–9% of the TP loads. The TN loads are dominated by the dissolved component and more particularly the total oxidized fraction (TON), which is composed of nitrate and nitrite and represents 76–82% of the annual TN transport. The remaining dissolved N species, ammonium (NH₄-N) and organic N (DON) account for 0·3–1·2% and 13–16% of the annual TN transport, respectively. The TPN and TPP fluxes closely reflect the suspended sediment dynamics of the study basins, which are in turn controlled by basin size and morphology. The dissolved inorganic nutrient fluxes are influenced by point source inputs to the study basins, especially for P, although the TON flux is primarily influenced by diffuse source contributions and the hydrological connectivity between the river and its catchment area. The dissolved organic fractions are closely related to the dissolved organic carbon (DOC) dynamics, which are in turn influenced by land use and basin size. The magnitude of the NH₄-N fraction was dependent on the proximity of the monitoring station to point source discharges, because of rapid nitrification within the water column. However, during storm events, desorption from suspended sediment may be temporarily important. Both the magnitude and relative contribution of the different nutrient fractions exhibit significant seasonal variability in response to the hydrological regime, sediment mobilization, the degree of dilution of point source inputs and biological processes. © 1998 John Wiley & Sons, Ltd.     

钒酸铵容量法测定岩石矿物中铀的不确定度评定

根据核工业行业标准"硫酸亚铁还原/钒酸铵氧化滴定法测铀"(EJ267.2-84)进行不确定度评定。通过不确定度来源识别,不确定度分量的量化,并以标定好的钒酸铵溶液滴定铀质量分数,得出方法本身带来数据的不确定度。对整个过程的不确定度来源和大小进行分析研究,应用统计学基础对数据进行科学处理。报告出了不同铀质量分数的合成标准不确定度和扩展不确定度。