粤北产铀与不产铀花岗岩中黑云母和绿泥石矿物化学特征及其与铀成矿的关系

发布时间：2018-05-12 21:50

  本文选题：黑云母 + 绿泥石　； 参考：《地学前缘》2017年05期

【摘要】：长江岩体和九峰岩体同为粤北诸广山复式岩体中的燕山期花岗岩体,它们的矿化特征具有显著差异,是诸广山地区典型的产铀岩体和不产铀岩体。本文利用电子探针对两岩体中黑云母和绿泥石开展了详细的矿物化学研究。结果显示,长江岩体中黑云母富铁贫镁,为铁叶云母,黑云母绿泥石化较为严重,绿泥石类型主要是蠕绿泥石和铁镁绿泥石,偏铁质绿泥石,主要形成于较还原环境;九峰岩体中黑云母为铁质黑云母,绿泥石化较弱,绿泥石类型多为蠕绿泥石、铁镁绿泥石和密绿泥石,偏镁质绿泥石。黑云母的成分特征显示,长江岩体结晶温度为600~650℃,氧逸度lgf(O2)为-16~-17,挥发分组成显示出相对高F、低Cl的特征;九峰岩体结晶温度为680~720℃,氧逸度lgf(O2)为-14~-15,挥发分组成显示出相对低F、高Cl的特征。综合地质特征和矿物化学特征可知,较低的温度和氧逸度、较高的挥发分F含量是岩体产铀的有利因素。
[Abstract]:The Yangtze and Jiufeng intrusions are both Yanshanian granitic bodies in the Guangshan complex in northern Guangdong Province. Their mineralization characteristics are different and they are typical uranium-producing and non-uranium-producing rocks in Zhuguangshan area. In this paper, detailed mineralogical studies of biotite and chlorite in the two rock masses have been carried out by using electron probe. The results show that biotite is rich in iron and magnesium in the Yangtze River, which is Ironite. Biotite green mud is more serious. The chlorite types are mainly vermicular chlorite and ferric chlorite, which are mainly formed in the reduction environment. In Jiufeng rock mass, biotite is ferric biotite, and green clay is weak. The chlorite types are vermicular chlorite, ferric magnesium chlorite and dense chlorite, and magnesite chlorite. The composition characteristics of biotite show that the crystallization temperature of the Yangtze rock mass is 600 ~ 650 鈩，

本文编号：1880291