云南个旧成矿区锡石-硫化物矿床原生金属分带形成的动力学机制  

THE DYNAMIC MECHANISMS OF PRIMARY METAL-ZONING OF CASSITERITE-SULFIDE DEPOSITS IN THE GEJIU ORE DISTRICT YUNNAN PROVINCE

作　　者：於崇文[1] 蒋耀淞[1] 

机构地区：[1]中国地质大学

出　　处：《地质学报》1990年第3期226-237,共12页Acta Geologica Sinica

摘　　要：个旧成矿区锡石-硫化物矿床内铜、锡密切共生,具有特殊的原生金属分带。本文采用动力学方法,利用计算机技术对该分带进行数值模拟。研究指出,矿床分带可能是由于多次矿化活动间歇、脉动式地相继发生而产生的。伴随成矿脉动所析离的含多种金属的成矿溶液,在其中的金属浓度与围岩中的浓度的特定比差下,依次沿断裂通道的差速输运继之以分异沉淀是个旧成矿区锡石-硫化物矿床内特殊原生金属分带形成的一种可能的动力学机制。Cassiterite-sulfide deposit is the principal type of ore deposits in the Gejiu ore district. In various ore fields of this ore district copper is closely associated with tin. From the center of ore formation outward and from bottom to top, a peculiar zoning of copper, tin-copper, tin-lead anti lead-zinc appears which is distinct from the zoning in Cornwall, England, and the typical geothermic zoning of Emmons. Metal-zoning of ore deposits is regarded as the spatio-temporal structure generated by dynamics of ore-forming processes. It is a 'self-organization' phenomenon in geochemical dynamic systems taking place under far-from-equilibrium conditions. Thereby a dynamic approach is taken to reveal the mechanisms of ore zoning. The authors set up a dynamic model for ore formation according to the physico-chemical conditions of ore formation, and then made use of computer techniques to simulate numerically the zoning of ore deposits. Investigation shows that the regular spatial zoning of copper, tin and lead appearing commonly in various ore fields in Gejiu probably resulted from multiple, intermittent and pulsatory mineralizations. The successive transports with diverse velocities along channelways of the ore-forming solutions containing different metals separated by processes accompanying pulsations, taking place under conditions of definite difference between metal concentrations in solutions and wallrocks, followed by differential deposition constitute possible dynamic mechanisms for the peculiar, primary patterns of metal-zoning of cassiterite-sulfide deposits in Gejiu ore district.

关 键 词：成矿区 锡石 硫化物矿床 金属 分带 

分 类 号：P618.205[天文地球—矿床学]