【作者】 隋延辉；

【导师】 戚长谋；

【作者基本信息】 吉林大学 ， 地球探测与信息技术， 2005， 博士

【摘要】 铬、镍属特种金属,在机械、化工、耐火材料等工业中具有特殊广泛的需求。本文从地质地球化学的角度,研究了全球范围内两类矿床的资源概况、时空分布及其成矿与幔源Si—O系统的关系。研究重点主要在后者。 铬、镍矿床与幔源岩石之间的关系密切,表现为矿体与岩体紧密伴生,矿体赋存于岩体内部,二者均属同源岩浆演化的不同产物。 长期以来,已有文献在论述两类矿床与幔源岩石关系时,常模糊岩石用词的概念。地壳中幔源岩石的存在分属3种不同产出单元,即岩区、岩体和岩相（为岩体的基本组成单元）。本文提出了以岩石产出的不同自然组合,来研究两类矿床与幔源岩石关系,奠定了坚实的理论基础。研究得出:对岩区而言,铬矿床的产出专属于超镁铁质岩区;镍矿床则专属于镁铁质岩区。对岩体和岩相而言,铬的成矿亦专属于超镁铁质岩体和岩相;在镁铁质岩区中,镍既可于超镁铁质岩体或岩相中成矿,亦可在镁铁质岩体或岩相中产出工业矿体。后者,镍的富集均优选于岩体岩石化学参数M/F比值最高的部位。本文对含矿载体造岩矿物和副矿物研究得出:载铬岩体和岩相中,造岩矿物橄榄石属于镁橄榄石;而载镍岩体和岩相的橄榄石均为贵橄榄石。区分两种可能含矿的副矿物标志信息为尖晶石类。岩体和岩相可能产出铬矿床的铬尖晶石富Cr和Mg;而可能产出镍矿床的尖晶石则相对富Fe、Al,贫Mg和Cr。 从Si—O系统和Cr³⁺、Ni²⁺离子能量的角度分析了镍优选于镁铁Si—O系统;铬优选于超镁铁Si—O系统的必然性。指出了两类矿床成矿的幔壳部更多还原

【Abstract】 Cr and Ni are two kinds of special metal. They are used widely in machine industry, chemicalindustry and refectory materials. In the paper, the general situation, distribution and the relation of the mineralization to the mantle-originating Si-0 system about two types of mineral deposits in the world are studied. And the main is the later.There is closed relation of Cr and Ni deposits to the mantle-originating rocks. The ore body occurs closely with intrusive body or in it. Both of them are the products of magma evolution in different phase.When discussing the relation of the two types of deposits to the mantle-originating rocks,someterms about rocks has been used indistinctly for a long time. Mantle-originating rocks in the crust can be divided into 3 types according to their occur unit: petrographic province, intrusive body and petrographic facies (basic compositional unit of a intrusive body). In the paper, we put out a new method to study the relation of the two types of deposits to mantle-originating rocks based on natural petrographic composition. According this study we have obtained following conclusion: 1) Petrographic province: Cr deposit occurs specially in ultmafic petrographic province and Ni deposit occurs specially in mafic petrographic province; 2) Intrusive body and petrographic facies: Cr deposit occurs specially in ultmafic intrusive body and ultmafic petrographic facies and Ni deposit occurs not only in mafic petrographic province but also in mafic intrusive body and petrographic facies. For the later, Ni deposit mainly exists in the position with the best M/F value. The study on rock-forming minerals and accessory minerals of ore-bearing intrusive bodies has revealed that the更多还原