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通过对云南老王寨金矿区新鲜、蚀变、矿比煌斑岩主元素对比,初步讨论了该区煌斑岩在蚀变、矿化过程中主元素的迁移规律,提出了三种煌斑岩主元素的判别方法;主元素对比结果对探讨煌斑岩与金矿化的成因关系有重要意义。 相似文献
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南镇沅金矿位于哀牢山变质带北段,夹持在哀牢山深大断裂带和九甲—墨江断裂带之间,偏向后者。矿田呈北西—南东向展布,由浪泥塘、老王寨、冬瓜林、搭桥箐和库独木五个矿段组成,其中冬瓜林矿段金属储量达大型。矿段内煌斑岩特别发育,同位素年龄证实煌斑岩与金矿化均为喜马拉雅期产物,煌斑岩型金矿石占矿段总储量的47％～48％,在国内外很具典型性。本文初步探讨了煌斑岩与金矿化的关系,总结出利用煌斑岩的找矿标志。 相似文献
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花岗岩成因分类简介与有关概念 总被引：2，自引：0，他引：2
花岗岩成因三级分类:第一级以形成方式(物理条件)分出不同花岗岩建造;第二级以物质来源(化学条件)分出不同花岗岩系列;第三级以地质环境(地质构造条件)分出不同花岗岩类型,并对有关术语涵义作了解释。 相似文献
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南岭诸广山花岗岩体的多次侵入活动和某些地球化学特征 总被引：7，自引：0，他引：7
The eleven successive magmatic activities of the southern mass of the Zhuguangshan granitic batholith can be divided into four intrusive episodes: Calidonian, Late Hercynian, Yenshanian and one of younger age, based on intrusive contact observations in the field, isotope ages and petrological-geochemical evidences, Genetically, rocks of each of the four episodes have their own features. The Yenshanian granites are characterized by a strong tendency toward differenciation. Variation in oxygen fugacity and in lithofacil character of the rocks indicates that the two earlier phases of the Yenshanian granites are emplaced in greater depth in a tectonick stable environment,while the later two phases are of relatively hypobyssal character under more active geological conditions. 相似文献
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REE Geochemical Indicatrices of Li—F Granite Liquid Segregation 总被引：1，自引：1，他引：0
The results of 118 REE analyses of Li-F granites from South China and other countries indicate that there are three variation types of REE pattern curves with different evolution trends from early to late stages of Li-F granite complex of from lower to upper petrofacies of the Li-F granite body;(1) the decreasing,(2) the increasing,and (3) the saltatory variation types.The first variation type is called the positive evolution type,attributed to crystallization differentiation.The second is called the reversion evolution type.which represents liquid segreation dominated by vapor-liquid distillation.The third is called the saltatory variation type,which is formed from liquid segregation dominated by immiscibilty,Therefore,the indicatices of liquid segregation dominated by immiscibility are the saltatory variation type of REE pattern evolution and the separation of the main evolution trend lines either from the sub-evolution trend lines or from the composition points of Li-F granites in the diagrams of REE-(La-Yb)N and La/Sm-La,The indicatrices of liquid segregation dominated by vapor-liquid fractional distillation are the reverstion evolution type of REE pattern curves and the main evolution trend lines of Li-F granites directing to the upper right-hand on the REE-La/Yb)N and La/Sm-La diagrams. 相似文献
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研究"钾质和钠质两个地幔富碱岩浆体系"的刍议 总被引：5，自引：1，他引：5
钾质富碱岩浆岩组成的岩带研究表明,这类岩石普遍富碱和CaO,高钾,富Rb,Sr,Ba和放射性元素Th,U等,Rb/Sr相对较低;稀土元素总量较高,强烈富轻稀土,δEu较小;ISr多数介于0.705～0.706之间;INd较低,铅同位素较均一.Sr-Nd-Pb同位素特征表明,该岩类岩石的岩浆来源于EMⅡ型地幔源区,岩浆很可能直接来源于钾质富碱地幔.钠质富碱岩浆岩带岩石具富碱、高钠(Na2O＞K2O)的特点,同时富钛及大离子亲石元素和相对富集Nb,Ta,Zr以及Rb/Sr偏高等;ISr相对低,而INd稍高.这类岩石起源于钠质的富碱地幔源区.这些异常地幔源的形成与地幔流体交代作用有关.而超深大断裂作为岩浆上升的通道,是钾质和钠质地幔富碱岩系形成的重要条件. 相似文献
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从云母微量元素特征探讨华南花岗岩的成因和演化 总被引：5，自引：1，他引：5
云母中微量元素可分为浅源指示元素和深源指示元素。浅源指示元素Nb、Ta、Sn、Li、Rb在南岭系列云母中的含量高于长江系列,而深源指示元素Co、Ni的含量长江系列大于南岭系列。云母中Nb、Ta、Sn、Li、Rb变化特征是自身成矿演化的直接示踪剂,而Co、Ni变化特征是Fe、Cu、Au、Mo(W)、Pb、Zn成矿演化的重要示踪剂。云母中Cu、Zn、W、Mo、U、Th等元素呈波动性变化,不能灵敏指示花岗岩的成因与演化。微量元素在云母中的选择分布主要受岩浆物源化学背景的制约,同时也受岩浆侵位和分异演化程度高低以及结晶的物理化学条件变化等因素的影响。 相似文献