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熊耳群火山岩中产出各种类型的金矿床,碲化物型(构造蚀变岩型)是金矿主要类型,该类型余矿以出现大量碲化物或富碲、硒为特征.硫化物δ ̄(34)S以较大的负值为特征,本文通过综合研究及与国内外行关矿床对比,认为该碲化物型金矿δ ̄(34)S负值的主要原因是地表水的渗透参与导致成矿热液物理化学条件改变,fo_2升高、pH值降低,从而引起硫同位素强烈分馏形成的。有关铅同位素组成具深源壳幔混合(染)特征,显示成矿物质来源于熊耳群富钾火山岩系。该类型金矿床成矿作用为上升岩浆与下渗地表水共同作用形成浅成热液系统,在剪切带内氧化环境下液体的稀释和冷却是金沉淀的主要原因。其成因类型应属浅成低温热液富碲化物型金矿。
Various types of gold deposits are produced in the Xiong’er Group volcanic rocks. The telluride type (structural alteration rock type) is the major type of gold deposit, and this type of ore deposit is characterized by a large amount of telluride or tellurite and selenium. Sulfide δ ~ (34) S is characterized by a large negative value. According to the comprehensive study and comparison with the ore deposits at home and abroad, the main reason for the δ ~ (34) S negative value of this telluride type gold deposit is the surface water The infiltration of hydrothermal fluids leads to the change of the physical and chemical conditions of the hydrothermal fluids, resulting in the increase of fo_2 and the decrease of pH value, resulting in intense fractionation of sulfur isotopes. The association of Pb isotopic composition with deep-source crust-mantle mixing (Dyeing) shows that the ore-forming material is derived from the Xiong’er Group of K-rich volcanic rocks. The mineralization of this type of gold deposit is caused by the fact that ascending magma and subsided surface water together form a shallow hydrothermal system. The dilution and cooling of the liquid in the shear zone are the main reasons for gold precipitation. The genetic type should be shallow epithermal hydrothermal rich telluride type gold deposit.