【摘要】 石英是自然界三大类岩石(岩浆岩、沉积岩和变质岩)和地壳中广泛分布的一种矿物,由于其具广泛分布性和化学稳定性,可以用于示踪地质历史并解释地质过程,因此近些年来引起了地质学家和矿物学家们的关注。本文结合实际科研就沉积岩、变质岩、岩浆岩以及一些热液矿床中石英的微量元素分布情况、石英在CL探测器耦合扫描电子显微镜(SEM-CL)和光学显微镜(OM-CL)下的颜色、发光强度及构造形貌特征等进行了探讨,并对石英中微量元素与CL颜色、发光强度及构造之间的关系进行了阐述,以此来提供研究石英的一个基础,最后简单论述了如何应用石英的CL特征来示踪或鉴定不同成因的含石英的岩石。更多还原

【Abstract】 Quartz,one of the most abundant minerals in the earth crust and also a very important mineral,occurs in large quantities in igneous,sedimentary and metamorphic rocks as well as in some hydrothermal systems.Petrogenesis,oxygen-isotope and trace element geochemistry,physical properties and defect microstructures of quartz and chalcedony have been studied by mineralogists and geologists in the past two decades,but some related problems are still in controversy.Due to wide distribution and highly stable nature of quartz,a variety of petrologic,isotopic and geochemical provenance techniques have been developed over the past two decades to study the provenance of detrital quartz.Integrated scanning electron microscope CL,electron microprobe CL and optical microscopy analysis of single quartz grains are fairly simple and inexpensive techniques and are efficient methods for visualizing microtextures in minerals that are invisible in conventional transmitted-bight microscopy.Quartz cathodoluminescene is commonly applied to decipher complex histories of geological process;however,the causes of quartz cathodoluminescence remain poorly understood,which may involve the variations in trace element concentrations in quartz.Different mechanisms of trace element uptake into the quartz lattice are discussed.For example,some trace elements in quartz may generally be incorporated into the crystal structure or bound in microinclusions(fluid mineral inclusions),and only a small amount of "foreign" elements can be incorporated into the crystal lattice;the substitutional incorporation of Al,Ge,Ti,Ga,Fe,H and P into Si position is well established.Cathodoluminescene may help establish the succession of paragenetic associations in minerals and a wide variety of rocks,such as growth zoning,randomly oriented microcracks and healed microfractures,homogeneous patchy or mottled CL,deformed lamelae,grain shattering and dissolution or alteration features.The distinguishable characteristics among volcanic rock,pluton,sedimentation,metamorphism and quartz in veins are systematically summarized on the basis of the authors’ recent research and literature reviews.The relationship between trace element geochemistry,cathodoluminescence texture and characteristics of cathodoluminescence are discussed.In the end of this paper,the authors attempt to provide a flow chart to illustrate the identification of various kinds of quartz in nature.更多还原