孟素红宝石矿床的矿物学特征研究

发布时间：2018-04-06 00:03

  本文选题：孟素红宝石　切入点：矿物组成　出处：《昆明理工大学》2016年硕士论文

【摘要】：缅甸孟素红宝石矿区发现于1991年,是已知大理岩型红宝石矿区中较新的矿床,目前国内对孟素红宝石矿床系统研究的较少。因此,系统研究该矿床矿物特征、矿物结构构造和成因,有助于深化对缅甸红宝石矿床的认识,对探讨大理岩型红宝石矿床有着重要意义。本文利用偏光显微镜、X射线粉晶衍射、红外光谱及激光拉曼光谱对孟素红宝石矿床的矿物结构及组分进行研究,运用电子探针分析技术测试矿床的化学元素成分。结果表明：(1)矿物结构主要为碎屑结构和粒状变晶结构。(2)矿床主体以白云石为主含有少量的磁黄铁矿和方解石,属于镁质大理岩；而围岩的矿物成分以方解石、云母为主,含有少量的石英、钠长石、透闪石、磁黄铁矿、绿泥石、石榴石等变质岩,变质岩相归属为绿片岩相。(3)电探结果显示外围围岩均为方解石含微量的Mg,主体矿床为白云石。在矿床的的围岩和主体矿床中都含有丰富的A1元素,在围岩中含有多种微量元素Si、Cl、K、Cr、Zn、Ti、Nb等。(4)依据显微结构和微量元素的分析,将孟素红宝石矿床的形成过程划分为区域变质成岩阶段和热动力作用成矿阶段。矿床主体白云石形成于区域变质作用早期中低温度和压力的变质环境中,随着温度升高到390℃-400℃左右时,方解石和白云石之间发生Mg2+交换,矿床围岩都转化为方解石：①原岩中所含的水及其他具挥发性的组分被分离出来,②岩石孔隙和裂隙中以水为主的溶剂也挥发出来,③从地壳中分泌出来含K、Na及Si02等化学物质的热液,通过以上三种途径析出的以H2O和CO2为主的化学活动性流体会进入方解石矿物中并赋存在其晶格缺陷或者包裹体内。之后在矿体与围岩的接触带上发生过多期次强烈的动力变质作用,使红宝石矿床的围岩受到强烈挤压,形成粒度小于0.5mm的矿物碎屑,并且形成新的矿物绢云母,同时在这一过程中交代生成钠长石。
[Abstract]:The Mengsu ruby deposit in Myanmar was discovered in 1991 and is a relatively new deposit in the known marble ruby deposit. At present, there is little systematic research on the Mengsu ruby deposit in China.Therefore, a systematic study of the mineral characteristics, mineral structure and genesis of the deposit is helpful to deepen the understanding of the ruby deposit in Myanmar and is of great significance to the exploration of the marble ruby deposit.In this paper, the mineral structure and composition of Mengsu ruby deposit are studied by means of X-ray powder diffraction, infrared spectroscopy and laser Raman spectroscopy. The chemical element composition of the deposit is measured by electron probe analysis (EPMA).The results show that the main mineral structure of the deposit is clastic structure and granular metamorphic structure. The main body of the deposit is dolomite, which contains a small amount of pyrrhotite and calcite, which belongs to magnesite marble, while the mineral composition of surrounding rock is calcite and mica.It contains a small amount of quartz, albite, tremolite, pyrrhotite, chlorite, garnet and other metamorphic rocks, and the metamorphic facies belong to greenschist facies.There are abundant A1 elements in the surrounding rock and main deposit of the deposit, and a variety of trace elements, such as SiClClC, K, Zn, TiNb, etc., in the surrounding rock.) based on the analysis of microstructure and trace elements,The forming process of Mengsu ruby deposit is divided into regional metamorphic diagenetic stage and thermodynamic metallogenic stage.The dolomite was formed in the metamorphic environment of low temperature and low temperature in the early stage of regional metamorphism. With the increase of temperature to about 390 鈩，

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