GYIG OpenIR  > 研究生  > 学位论文
云南都龙锡锌多金属矿床找矿矿物学与成矿年代学
王小娟
导师刘玉平、缪应理
2014
学位授予单位中国科学院研究生院
学位授予地点北京
学位名称硕士
学位专业地质工程
关键词夕卡岩 石榴子石 辉石 锡石u-pb年代学 都龙锡锌多金属矿床 云南
摘要都龙锡锌多金属矿床,位于云南省马关县都龙镇,是我国最大的锡石硫化物矿床之一。由于该矿床地质现象复杂,岩浆、构造、地层等因素均表现出一定的控矿意义,长期以来矿床成因认识存在较大争议,在一定程度上制约了深部及外围找矿。本论文在野外地质调查基础之上,通过光学显微镜对该矿床中的夕卡岩矿物及伴生金属矿物进行了详细的观察,利用电子探针、LA-ICP-MS微区原位技术对夕卡岩矿物开展了系统的定性与定量分析,以揭示夕卡岩的形成过程、矿床成因及找矿意义。在已有的成岩-成矿年代学资料基础之上,通过锡石LA-MC-ICP-MS U-Pb同位素定年,以进一步明确成矿时代、甄别矿床成因。论文取得的主要认识有: (1)都龙锡锌多金属矿床的地质地球化学特征表明,该矿床为岩浆-构造-地层复合控矿的岩浆热液成因矿床。 (2)石榴子石电子探针数据及LA-MC-ICP-MS微区原位分析数据表明,石榴子石成分与矿化关系密切。与W、Mo矿化有关的石榴子石主要为钙铝榴石,分布在矿区距深部花岗岩体约0-100m的范围内和250~300m的范围内。因此,根据石榴子石成分在垂向上的变化及与之相关的矿化规律,可以用于深部找矿。Sn元素在石榴子石中含量较高,结合面扫描图像显示,Sn主要呈微细粒锡石围绕石榴子石边部分布,部分呈类质同相分散于石榴石晶格中。根据石榴子石主-微量元素与Sn矿化的关系,推测Sn矿化主要分布在距深部花岗岩体距离为50-300m之间,80m处,锡含量最高,随后距深部花岗岩距离增加,锡含量逐渐降低,推测可以在80m附近寻找富Sn矿体。 (3)辉石电子探针及LA-ICP-MS微区原位分析数据表明,辉石成分与矿化关系复杂。随距深部花岗岩体距离的增加,Sn、Zn、Cu等金属元素的含量变化较大,且与之矿化有关的辉石,成分跨度较大,从透辉石到钙铁辉石均有,锰钙辉石含量亦变化较大,规律性不明显。 (4)石榴子石、辉石、角闪石、绿帘石、绿泥石、金云母等夕卡岩的电子探针数据表明,该矿床夕卡岩在形成过程中,早期处于一个相对还原的酸性环境,随后逐渐过渡到相对氧化的碱性环境;晚期退化蚀变阶段,氧化性增强,氧逸度具有逐渐升高的趋势。 (5)LA-MC-ICP-MS 锡石U-Pb定年结果表明,都龙矿区大规模锡矿化主要形成于72.4~96.6Ma,属晚白垩纪,与燕山晚期老君山岩浆热液活动关系密切。对比个旧、白牛厂和都龙等三个超大型锡多金属矿床的成岩-成矿年代学数据,表明滇东南地区存在燕山晚期大规模的花岗岩成岩-锡多金属成矿作用。 (6)研究表明,岩浆热液是该矿床形成的关键因素,应该围绕花岗岩体、特别是隐伏花岗岩及其接触带,结合有利的构造及地层岩性地段来展开深部及外围找矿。野外地质调查及室内研究表明,钙铝榴石、透辉石-钙铁辉石、符山石等早期夕卡岩矿物在距深部花岗岩体较远部位仍有出现,并伴随一定的金属矿化,推测都龙矿区成矿作用与多期次岩浆热液作用有关。因此,找寻W、Mo等高温矿化,不应局限于在深部隐伏岩体附近,也应重视浅部斑岩脉附近的有利部位
其他摘要The Dulong tin-zinc ploymetallic deposit, which is one of the largest cassiterite-sulfide deposits in China, locates in the Maguan county, Yunnan Province, China. Due to the complexity of this deposit geological phenomenon, the magma, tectonic, formation and other factors have showed some certain ore-controlling significance, so that the genesis has been controversial greatly for a long time, and to some extent, seriously to restrict the deep and periphery prospecting. Based on the geological survey, by optical microscopy to carry out the detailed observation of the skarn minerals and metallic minerals, taking advantage of the electron microprobe and LA-ICP-MS in-situ technique to conduct systematically qualitative and quantitative analysis, this paper is in order to reveal the formation process of skarn, ore genesis and prospecting significance. Based on the conventional rock-forming and ore-forming chronology data, the U-Pb isotopic dating of cassiterite by the method of LA-MC-ICP-MS had been used to futher define mineralization age and to distinct genesis. The main conclusions are listed below. (1)The geological and geochemical characteristics of Dulong tin-zinc ploymetallic deposit indicated that this deposit was a magmatic hydrothermal genesis deposit controlled by magma-tectonic-formation composite factors. (2)The analytical data of garnet electron probe and in-situ micro-area LA-ICP-MS showed that the composition of garnet was closely associated with mineralization. The garnet was mainly grossular related with the W, Mo mineralization, which was mainly distributed in the range of 0-100m, 250-300 from the deep granite rock, respectively. Accordingly, garnet compositional changes in the vertical and related mineralization rules can be used to deep prospect. Sn element of garnet was in higher levels. Combined with the surface scan images, Sn were mainly distributed around the edge of garnet in the form of fine grain of cassiterite and some were isomorphously scattered in garnet lattice isomorphism. According of the relationship between garnet major- trace elements and Sn mineralization, it was suggested that Sn mineralization is mainly distributed in the range of 50-300m from the deep granite rock. At 80m, tin content was the highest, then gradually reduced with the increase of distance from deep granite, so we can looking for the rich Sn orebody near 80m. (3) The analytical data of pyroxene electron probe and in-situ micro-area LA-ICP-MS showed that the relationship between pyroxene composition and mineralization was complex. With the increase of distance from deep granite, the content of metal elements such Sn, Zn, Cu changed greatly and the pyroxene component associated with relevant mineralization had larger span, from diopside to hedenbergite. At the same time, manganese content of calcium pyroxene also changed greatly, regularity is not obvious. (4)Electron probe data of skarn minerals such as garnet, pyroxene, hornblende, epidote, chlorite and phlogopite indicated that the early skarn had been in an acidic environment of relative reduction, then gradually moved to the alkaline environment of relative oxidation. In the later alteration stage of degeneration, oxidation enhanced and oxygen fugacity had gradually increased. (5)The U-Pb dating results of cassiterite by the method of LA-MC-ICP-MS indicated that the large-scale tin mineralization of the Dulong orefield had mainly formed in 72.4~96.6Ma regarded as the late Cretaceous, which related closely to the later Yanshanian magmatic hydrothermal events. Compared to the data of the rock-forming and ore-forming chronology from the three super large tin polymetallic deposits of Gejiu, Bainiuchang, Dulong, it was further suggested that there were the Late Yanshanian large-scale granitic magmatism and relative tin polymetallic mineralization in the southeastern Yunnan. (6)Studies showed that magmatic hydrothermalism was the crucial factor for the formation of this deposit, so we should be around the granite, especially concealed granite and the contact zone, to expand the deep and periphery prospecting combined with a favorable structure and the stratigraphic lithology. Geological survey and laboratory study revealed that the early skarn minerals such as grossular, diopside-hedenbergite, vesuvianite still appeared away from areas of deep granite and was followed with certain metals. Hence, it was supposed that the mineralization of Dulong orefield was related to the multiphase magmatic hydrothermalism. So looking for the high-temperature mineralization such as W, Mo, we should not be limited to the area near the deep concealed granite and also should pay attention to the advantageous parts near the shallow granite porphyry vein.
学科领域矿床地球化学
语种英语
文献类型学位论文
条目标识符http://ir.gyig.ac.cn/handle/352002/5918
专题研究生_研究生_学位论文
推荐引用方式
GB/T 7714
王小娟. 云南都龙锡锌多金属矿床找矿矿物学与成矿年代学[D]. 北京. 中国科学院研究生院,2014.
条目包含的文件
文件名称/大小 文献类型 版本类型 开放类型 使用许可
云南都龙锡锌多金属矿床找矿矿物学与成矿年(9868KB) 暂不开放使用许可请求全文
个性服务
推荐该条目
保存到收藏夹
查看访问统计
导出为Endnote文件
谷歌学术
谷歌学术中相似的文章
[王小娟]的文章
百度学术
百度学术中相似的文章
[王小娟]的文章
必应学术
必应学术中相似的文章
[王小娟]的文章
相关权益政策
暂无数据
收藏/分享
所有评论 (0)
暂无评论
 

除非特别说明,本系统中所有内容都受版权保护,并保留所有权利。