华南某花岗岩型铀矿床成矿机理的铀铅同位素体系研究     

李耀菘  李喜斌 《地球化学》1985,(1):20-26

The uranium deposit studied in this paper occurs in a Precambrian (Xuefengian)granite batholith. The emplacement age of the granite is 760 m.y. The average content of uranium in the granite is 7 ppm, but the yield of leachsd U is higher With an average of about 33.8%. The granitic rocks, contain; Some uraninite. Uranium mineralization mainly takes the form of siliceous veins With an age of 47 m.y. K-feldspar. present in the granite and pyrite associated with pitchblende were massspectrometrically analyzed for Pb isotopic compositious, characterized by anomalous lead. A reasonably linear array can be seen on the ^207Pb/^206Pb--^205Pb/^204Pb plot, implying a genetic connection between the rock and the ore, and a derivation of rock-forming materials from. a uranium-rich source. According to the continuous-growth model for anomalous lead, evolution, two isochrons give the. ages-of about 764 m.y. and 708 m.y.for ore-forming materials, close to the emplacement age of .the granite batholith. This indicates that the ore-forming materials came from the granite batholith. Eight granite samples collected from the mining .area were analyzed, but no uranium-lead ages could be worked out because of the pregressive destruction of the closed U-Pb isotopic system since granite emplacement, which resulted in the loss of uranium(78%). It can be imagined that in the period of continental weathering the surface water would infiltrate downwards, leaching out large amounts of uranium from the granitic rocks to form infiltration solution. The solution was heated at great depth and then found its way upwards, on which it dissolved constantly U from the rocks to form the uranium deposit.  相似文献   

济源:筑牢资源保护新防线     

刘晓玲  张秀山 《资源导刊(河南)》2007,(4)

济源市是依托"五小工业"逐步发展壮大起来的新兴工业旅游城市.近年来,随着济源工业经济的迅猛发展,已有豫光金铅、济钢、金马焦化、豫源电力、浮法玻璃、豫港陶瓷等近15家大型企业,年需矿产品上亿吨.  相似文献   

无火焰原子吸收发光光度法测定盐样中痕量铅     

陈方正 《地质实验室》1990,6(1):18-20

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厦门-金门海域表层沉积物中重金属铜铅锌镉的含量分布   总被引：7，自引：0，他引：7  

洪丽玉  陈伟琪  洪华生  徐立  王新红 《台湾海峡》2000,19(4):441-445

1995年 1 0月调查研究了厦门 金门海域表层沉积物中重金属Cu、Pb、Zn、Cd的含量 ,Cu、Pb、Zn、Cd的平均浓度分别为 1 6 .6、5 2 .6、1 0 4、0 .2 0 5 (× 1 0 -6m/m ,干重 )。根据底质标准 ,Pb、Zn明显超标。从平面分布看 ,厦门岛南部海区(XJ1～XJ4号站 )的重金属含量高于北部海区 (XJ5～XJ7号站 ) ,北部海区又高于东部海区 (XJ9、R1、R2号站 ) ,尤其是南部海区的XJ1、XJ2、XJ3号站其含量明显较高。这一分布特征表明除了九龙江河流对该海域的贡献外 ,西海域的输入也是一个重要的因素。位于东部海区的XJ9、R1、R2号站 ,从XJ9至较靠近金门的R1、R2号站 ,重金属Cu、Pb、Zn、Cd的含量略有回升 ,其来源有待于进一步分析探讨。  相似文献   

含澄江动物群地层的Pb-Pb同位素定年   总被引：2，自引：0，他引：2  

常向阳  陈良忠  胡世学  王江海  朱炳泉 《地球学报》2004,25(2):181-184

对含澄江动物群的地层样品进行了Pb同位素定年研究。经测定未受风化作用影响的 2 0个黑色页岩样品给出了5 34± 6 0Ma左右的Pb Pb等时线年龄 ,应代表了澄江动物群的下限年龄。该年龄较以往采用Rb Sr和40 Ar 3 9Ar等定年方法所获得的年龄更为年轻。  相似文献   

藏北安多县抱布德铅多金属矿床地质特征及找矿方向          下载免费PDF全文

王维  郑占雾 《山东国土资源》2014,30(5)

抱布德铅多金属矿产于硅质岩、灰岩中,围岩主要为灰岩、少量泥岩,蚀变普遍,构造发育。通过野外地质工作,结合已有资料,从区域地质特征及构造演化成矿方面对抱布德铅多金属矿床进行分析,初步分析矿床与区域构造运动、广泛发育的NW向断裂、三叠纪地层有关,矿区断裂构造、硅质岩为以后探矿的重点区域。  相似文献   

New advances in the study of Alpine glaciations     

ShangZhe Zhou 《寒旱区科学》2014,6(1):0001-0007

The European Alps is the birthplace of glaciology and in particular Quaternary glaciology and for over one hundred years has been a model region for studying mountain glaciations. In this paper, we review the achievements from this region, which will benefit glaciological studies of the Tibetan Plateau, China. According to new evidences of glaciofluvial de- posits discovered in valleys and forelands of the Alps, researchers have progressed from an original four Pleistocene gla- ciations to seven glaciations： Biber, Donua, Gtinz, Haslach, Mindel, Riss and WOrm. The earliest one Biber possibly oc- curred between the Pliocene and Pleistocene, but the chronology before Riss is still in doubt. Recent years, Riss and Wtirm glaciations have been supported by a large numbers of cosmogenic exposure dating. In particular, cosmogenic nuclide exposure dating has been carried out for different moraine boulders in numerous valleys, which reveals a series of climatic change events, and they are comparable to post-glacial age records of northern Europe. The advancement of glaciological studies in the Alps is important in promoting glaciological research in the Tibetan Plateau.  相似文献   

安徽庐江泥河铁矿矿床地球化学特征及其对成因的制约   总被引：6，自引：2，他引：4  

张舒  吴明安  赵文广  张宜勇  李小东  汪晶 《岩石学报》2014,30(5):1382-1396

泥河铁矿位于长江中下游成矿带庐枞中生代火山岩盆地中,矿床具有典型玢岩型铁矿的地质特征,是研究玢岩型铁矿成因的良好对象。本次工作在详细的野外观察及室内研究的基础上,对泥河铁矿主成矿期矿石矿物的稀土元素、硫同位素及铅同位素进行了分析测试工作。主成矿期磁铁矿、黄铁矿稀土元素配分模式呈现LREE富集、HREE曲线平直、Eu轻微负异常的特征,与赋矿砖桥组熔岩、闪长玢岩的稀土元素配分模式较为一致,结合矿石矿物与围岩的铅同位素特征,推测成矿金属元素主要来源于赋矿的火山-次火山岩,可能有少量壳源物质的加入。黄铁矿与硬石膏的硫同位素表现出双峰式分布的特征,说明岩浆活动与三叠纪膏盐层均对硫有所贡献。三叠纪膏盐层在泥河铁矿的成矿过程中,不仅仅是重要的矿化剂,同样是铁质沉淀的氧化剂。综合矿床地质与地球化学特征,认为泥河铁矿是由次火山岩体演化产生的含矿高温热液在闪长玢岩穹窿顶部,通过交代充填作用形成的玢岩型铁硫矿床。  相似文献   

藏南扎西康锑硫盐多金属矿床成矿物质来源分析:兼论北喜马拉雅成矿带主要矿床矿质来源的差异性     

李关清  顾雪祥  程文斌  章永梅  张岩  代鸿章  吕鹏瑞  张兴国  夏抱本 《地学前缘》2014,(5)

扎西康矿床是北喜马拉雅Sb-Au成矿带上一个较为特殊的大型-超大型锑硫盐多金属矿床,赋存于下侏罗统日当组。矿床容矿围岩以黑色含炭钙质板岩为主体,矿体严格受近南北向和北东向两组断裂控制,呈脉状、透镜状产出。矿石中金属矿物除闪锌矿、方铅矿、辉锑矿等常见硫化物之外,还大量发育硫锑铅矿、脆硫锑铅矿、黝铜矿、车轮矿等硫盐矿物;非金属矿物主要为菱锰矿、菱铁矿、石英和方解石,矿床的形成经历了中低温热液期和表生期。元素地球化学和硫、铅同位素研究表明,矿床中矿石和矿化岩石除富集Sb、Pb、Zn、Ag等主成矿元素外,还富含MnO、Cu、As、Cd、Au等矿化元素;容矿地层中Sb、As、Ag、Pb、Zn、Mn等成矿元素也较为富集,具备提供成矿物质的能力;矿石硫化物的硫同位素组成与容矿地层接近,指示成矿流体在运移过程中萃取了容矿地层中的Sb、As、Ag和S等组分,日当组为硫的主要提供者;铅同位素具变质结晶岩系特征,指示变质结晶岩系及与之有亲缘关系的淡色花岗岩为成矿提供了Pb、Zn等金属组分。北喜马拉雅成矿带主要典型矿床在矿质来源上存在着明显的差异,成矿带中部和北部的Sb和Sb-Au矿床的成矿物质主要来自于容矿地层和矿区岩浆岩(包括中生代中基性岩和新生代闪长岩),而在成矿带南部的Sb(-Au)-Pb-Zn矿床中,除容矿地层和矿区岩浆岩提供Sb、As、S之外,变质结晶岩系(拉轨岗日岩群)及与之有亲缘关系的淡色花岗岩也为成矿提供了Pb、Zn等金属组分。  相似文献   

德钦佛山托罗铅锌矿地质特征及成因分析     

马安妮  李蓬博  孟志勇  李守奎 《云南地质》2014,(1):141-143

在对该区野外地质调查的基础上,本文对该铅锌矿化带的成矿构造背景、矿化体特征进行了初步分析与总结,认为该矿受区域构造断裂控制,矿床类型为中低温热液脉状铅锌多金属矿床.该区成矿地质条件优越,矿化体较多,矿体在走向和倾向延伸方向仍可有新突破,并有找到新矿体的可能.  相似文献