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171.
A review of Australian salt lakes and associated mineral systems   总被引:1,自引:0,他引:1  
This study reviews the available information for over 1200 Australian salt lakes including in areas that have little or unreliable data. Publicly available groundwater hydrogeochemical datasets for the Australian arid zone are particularly sparse, inconsistent and of variable quality. Many datasets in the vicinity of salt lakes only report salinity or total dissolved solids, with no data for constituent cations and anions, and no appreciation of the hydrological and geomorphic evolution of the lakes. To overcome these limitations and to provide a broad-scale context, we developed mineral systems models to assess the potential of Australian salt lakes for potash, lithium and boron deposits. These models show that an important control on the potential of salt lake systems to form economic deposits of potash, lithium or boron is hydrogeological connectivity between leachable source rocks and the lakes. The assessment of the mineral potential was carried out in two stages. The first stage selection was based on the presence of favourable source rocks in the salt lakes’ catchments. The mean values of concentration in each catchment were derived from whole rock, sediment and groundwater geochemical datasets by averaging the values in samples (separately for each of the three datasets) located in the catchment and assigning this value to the catchment's salt lakes. The second stage selection was carried out by analysing available chemical data of groundwater in proximity to the salt lake systems delineated in the first stage. As a result, six regions were identified as having the highest potential, for potash in particular, but also for lithium and/or boron deposits. These are: the Lake Frome/Central Gawler Region of South Australia; two regions in the Northern Territory: the central western region extending into Western Australia, and the Lake Woods region; and, in Western Australia, the Lake Disappointment region, the north east Yilgarn and south east Yilgarn regions.  相似文献   
172.
四川省阿坝州党坝伟晶岩型锂辉石矿床是可尔因稀有金属矿集区内的典型矿床。通过对党坝锂辉石矿物流体包裹体研究结果表明:1)锂辉石矿物中富集气液两相水溶液包裹体、含CO2三相包裹体,见少量含子矿物三相包裹体;流体包裹体均一温度为260℃-314℃,盐度为w(NaCl,eqv)=2.96%~9.08%,指示党坝矿床成矿流体具中温、低盐度特征。2)激光拉曼光谱分析气相成分主要为H2O,CO2次之,见少量的CH4、N2;液相成分以H2O为主,含少量CO2、CH4;含子矿物包裹体的子晶矿物为方解石。3)成矿流体应属H2O-NaCl±CO2±CaCl2±CH4±N2体系,流体密度为0.72~0.88g/cm3,认为在成矿流体主要来源于岩浆热液。4)气液两相水溶液包裹体、含CO2三相包裹体以及含子矿物三相包裹体共存于同一视域中,且均一温度相近,表明流体发生沸腾或不混溶作用导致相分离并发生锂辉石聚集沉淀是党坝锂辉石矿床形成的主要原因。  相似文献   
173.
针对广西晚二叠世聚煤盆地中锂、镓元素地球化学异常问题,选取扶绥和贤按两个典型晚二叠世煤田,通过系统取样测试,研究煤系中锂、镓丰度,并结合成矿地质背景,分析煤中锂、镓的富集控制因素。结果表明:研究区锂和镓均有一定的工业前景,扶绥煤田锂和镓的平均丰度分别为83.5 μg/g和30.8 μg/g;贤按煤田锂、镓丰度分别为199.1 μg/g和33.4 μg/g。锂主要富集于合山组底部K1煤层、炭质泥岩及铝土岩段,而镓在合山组底部各岩性中的丰度并无明显差异。云开古陆及周边中酸性火山岩是锂、镓物质的基础来源,合山组底部高铝沉积岩系可能是合山组K1煤层中锂、镓的直接物源。镓元素在各岩体之间的迁移比较活跃,其物源区的含量水平起主导作用,而锂元素的富集除了受控于物源外,沉积环境及后期地质作用的影响更为明显。研究成果为广西煤系中锂、镓资源的勘查预测及其综合利用提供科学依据。   相似文献   
174.
光学遥感在识别花岗伟晶岩型锂矿床中的应用   总被引:2,自引:2,他引:0  
花岗伟晶岩型锂矿是一种重要的锂矿资源,近年来,光学遥感技术在花岗伟晶岩型锂矿找矿应用中效果显著,开启了遥感找锂矿的研究热潮.本文基于对全球及国内花岗伟晶岩型锂矿空间分布特征、成矿地质特征的综合分析,归纳总结了目前伟晶岩型锂矿识别的光学遥感数据源及技术方法:ASTER、Landsat-8等中等分辨率影像具有较高的光谱分辨率,可利用锂矿独特的光谱特征,通过信息增强方法来识别锂矿;而WorldView-2、WorldView-3等高分辨率影像具有较高的空间分辨率,可以通过图像色彩增强方法提取到细小的伟晶岩型锂矿露头.提取技术方法包括RGB组合、波段比值、主成分分析、辐射增强等,RGB组合方法虽然能在锂矿提取中起到一定作用,但主观因素影响较大,且提取出的伟晶岩是否含有锂矿需要进一步研究;主成分变换以及波段比值主要依据锂矿的光谱特征信息,得出的结果具有客观性和科学性,但提取精度还需要提高;辐射增强通过改变影像的像元灰度值来突出花岗伟晶岩型锂矿信息,能够很好的解决花岗伟晶岩型锂矿和围岩光谱信息差异细微的技术瓶颈.最后,本文指出了多源遥感数据协同应用、自动化及智能化算法的引入等将是开展花岗伟晶岩型锂矿遥感找矿的发展趋势.  相似文献   
175.
2016—2018年中国地质调查局天津地质调查中心联合西藏自治区地质矿产勘查开发局第五地质大队组建盐湖调查队伍,针对西藏羌塘盆地西段泽错盐湖开展调查评价工作,探获大型锂(硼)矿产地1处。泽错湖表水体长16.3 km,宽3.3~11.3 km,湖表面积113.8 km2。湖水深度变化较大,四周水较浅,逐渐向中间变深,最深处达44 m,湖水平均深度为24 m,湖面海拔4940 m。泽错盐湖位于藏北羌塘—三江复合板块内,矿区第四纪地层可划分为更新统湖积,全新统现代湖水,全新统冲洪积,全新统冲积和全新统湖积。湖盆可划分基岩裂隙水层、亚砂土孔隙含水层、亚黏土孔隙含水层和湖表卤水4个水文地质单元。经计算直接补充到湖盆表面的大气降水量为1.081×107m3/a,地表水补给湖水量为8.262×107m3/a,地下水补给量为2.052×107m3/a,泽错年补给水量为11.395×107m3/a左右。自然蒸发为泽错湖盆的主要排泄方式,泽错湖水年蒸发量为12.745×107m3/a,年均水量变化值为1.35×107m3/a,地表水补给湖水带入的总盐量为7.8×104t/a。泽错湖盆卤水中主要成盐元素有Cl-、Na+、SO42-、K+、CO32-、HCO3-、B2O3、Mg2+、Li+等,平均矿化度41.57 g/L,pH值为9.31,泽错湖水为高矿化度盐水,水化学类型为硫酸钠亚型。泽错盐湖LiCl平均品位为376.02 mg/L,LiCl资源量为102.68×104t,远景规模达到大型;B2O3平均品位为840 mg/L,B2O3资源量为229.38×104t,远景规模达到大型。在综合分析锂、硼资源需求、提锂技术、盐田建设、气候条件、经济价值等方面的基础上,对泽错盐湖的开发利用前景进行了展望。  相似文献   
176.
运用热红外反射光谱技术建立花岗伟晶岩型锂矿识别方法,可以用来对目标靶区开展含矿性快速评价工作.锂辉石在热红外波段主要存在四个吸收峰,波长位置分别位于8 600 nm,9 150 nm,9 350 nm和11 670 nm处附近,其中11 670 nm处的吸收峰是锂辉石矿物的特征吸收峰,吸收深度为0.021 9~0.04...  相似文献   
177.
Two tracer experiments have been carried out at an enclosed catchment in southern Norway. The catchment was brought to steady state with respect to rainfall and runoff prior to the tracer addition. A known concentration of lithium bromide was then added to the rainfall for the duration of each event. The tight control on tracer concentration and rainfall amount enabled assessment of the contribution of old and new water to runoff, the dominant flow pathways and soil water residence times during a storm event. A significant volume of ‘old’ water contributes to runoff despite the hydrologically responsive nature of the catchment and several hours of tracer injected rainfall are required before ‘new’ water becomes the dominant runoff source. After 34 h of tracer injection, ‘new’ water apparently contributes c. 83% to instantaneous flow and c. 55% of the total tracer input to the catchment has been lost in runoff. Recovery of the tracer from soil water indicates that the organic soil surface layer is the dominant flow pathway for rainwater through the catchment and that a significant pathway also exists at the soil–bedrock interface. New water is retained in deep pockets of soil for several days. Assessment of the conservative behaviour of the tracer suggests that 10–14% of the input Br is retained in the soil and the tracer is not conservative. Laboratory experiments indicate that sorption of Br to organic soil is the likely mechanism of retention. This process is probably concentration dependent and will have occurred predominantly during the initial period of tracer application. Copyright © 2000 John Wiley & Sons, Ltd.  相似文献   
178.
金属锂提取工艺比较分析   总被引:8,自引:0,他引:8       下载免费PDF全文
简述了金属锂的应用以及熔盐电解法和真空热还原法提取金属锂的技术特点,评述了两种方法的优缺点并提出了改进方法,对金属锂冶炼的未来发展进行了展望。  相似文献   
179.
ABSTRACT

The objective of the article is to show how the demonstration project and battery ferry Ampere has contributed to a greening of public ferry procurement in Norway. Building on theories on demonstration projects in transition studies and institutional work, the author argues for a more integrated focus than hitherto on the dynamic interplay of materiality, organization, and discourse in demonstration projects, and how the agency of actor networks and the materiality connected to demonstration projects can affect institutional change accompanying transition processes. This is done by conceptualizing Ampere as a ‘performing project’: a complex of discursive and organizational strategies of framing and lobbying deployed by the actor networks connected to it and its materiality. Methodically, the author draws on semi-structured interviews and document analysis. The results suggest that Ampere’s ‘performance’ has contributed to changes in national and regional ferry procurement practices and been vital for an emerging maritime battery niche.  相似文献   
180.
7Li由于其中子反应截面较小,可以用作核工业中的中和剂、载热剂,其自然丰度为92.5%,为达到核工业应用需要的丰度(99.99%),必然要进行7Li的富集。β-双酮及其衍生物为常见的具有富集7Li效应的螯合剂。以含有季铵盐和1-羟基-4-对甲苯胺基蒽醌的苯甲醚溶液作为有机相,碱性锂盐溶液作为水相,两相振荡混合得到富集7Li的沉淀,并对其分离性能进行考察。研究发现随着少量季铵盐的引入,在高碱性的条件下螯合剂利用率以及沉淀相7Li丰度得到了很大的提升。还优化了反应条件,计算了同位素交换的热力学参数。  相似文献   
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