自然界酸性溶液的形成和向成矿溶液演化机理──表生循环水向成矿溶液演变机理之(二)  

FORMATION OF ACIDIC SOLUTIONS IN NATURE AND MECHANISM OF THEIR EVOLUTION TOWARD ORE-FORMING SOLUTIONS──Ⅱ. A STUDY ON THE MECHANISM OF TRANSFORMATION OF HYPERGENE CYCLING WATER INTO ORE FLUIDS

作　　者：陈福[1] 王中刚[1] 朱笑青[1] 

机构地区：[1]中国科学院地球化学研究所,贵阳550002

出　　处：《矿物学报》1997年第4期386-398,共13页Acta Mineralogica Sinica

基　　金：中国科学院矿床地球化学开放研究实验室资助

摘　　要：对成矿溶液性质的认识是矿床成因和预测矿床的理论基础。到目前为止，讨论“酸性成矿溶液成矿机理”的报导甚少。作者认为，既然火山气体冷暖水是强酸性的，地壳中的岩浆气液冷凝水必然也是强酸性的，其pH接近于零，由岩浆气液冷凝水演变成的合矿溶液及其成矿作用在地质中可能是相当普遍的现象。本文讨论了岩浆气液冷凝水向含矿溶液转变的条件和机理、含矿溶液成矿的条件和机理，以及随后溶液又向近中性卤水成分演变的规律。本文以扬子地块西南缘低温热液交代改造型矿床为例，揭示地壳中酸性含矿溶液成矿的普遍规律及地质证据。The knowledge of the properties of ore-forming solutions is the theoretical basis for metallogenetic theory and ore deposit diagnosis. Immersing-dissolving experiments at elevated temperature were done on the source rocks of different lithological characters from the region of Southwest China by using seven hypergene waters including volcanic hot spring water from Tengchong,Yunnan, hoevellite brine from Mengye Well, oil/gas-bearing water from Chishui, Guizhou, oceanic water from Qingdao, natural rain water from Guiyang, Guizhou, humic acid-bearing water extracted from soil samples taken from the Guiyang Forest Park, and artificially prepared Cl-bearing acidic water. In addition, simulating experiments were also done on the weathering-leaching of the four types of source rocks by three kinds of meteoric water. The experimental results show that acidic water is most favorable to the formation of ore-forming element-high solutions; humic acid-bearing water is also, in some cases, favorable to the formation of polymetal-high ore-forming solutionsl but modern rain water, volcanic hot spring water from Tengchong, hoevellite brine from Mengye Well, oil/gas-bearing water from Chishui, Guizhou, and oceanic water from Qingdao are nearly neutral and slightly acidic waters seam impossible to be transformed into major metal (Fe,Mn,Cu,Pb, Zn, etc.)-high ore-forming solutions. The presence of strong complexing agents in certain amounts in the solutions may play an important role in the transport and mineralization of some precious metals, rare and dispersed elements.

关 键 词：表生循环水 溶解实验 矿床成矿 成矿溶液 

分 类 号：P611[天文地球—矿床学]