摘要
花岗岩内热液交代充填型铀矿床，根据现有的认识大致可以分成两个系列。一是酸性蚀变交代充填系列，形成铀-微晶石英型、铀-萤石型、铀-粘土型铀矿床。另一是碱性蚀变交代系列，形成碱交代(岩)铀矿床。前者从成矿前岩石蚀变到成矿后脉体充填，均不同程度地发育有黄铁矿。此外，尚有少量方铅矿、白铁矿、闪锌矿、辉铝矿、黄铜矿等。
Researches on sulphur isotopes for hydrothermal uranium deposits with acid alterations shed some light on the genetic aspect of hydrothermal uranium deposits. Based on studies on uranium deposits of different genesis, it is concluded that δS34 of sulfide in hydrothermal uranium deposits derived from residual magma is within the range of +2‰- - 2.6‰, approximately the same as sulfur from meteorite. δS34 of sulfide for polygenetic hydrothermal uranium deposits is slightly lighter than sulfur from meteorite and varies within a restricted range (6.7‰), averaging -10.15‰. Two intervals can be recognized with respect to sulphur isotopic compositions in palin-genetic hydrothermal uranium deposits. δS34 of sulfide from diagenesis, autometamor-phism and hypothermal stages are similar to sulfur from meteorite. On the other hand, for the stage starting from the alteration of uranium mineralization to the formation of uranium deposits and postmineralization the average sulfide isotopes is - 7.89‰, with a wider range of δS34 variation (13.7‰), which can be attributed to the enrichment of δS34 in palingenetic hydrothermal solutions.
出处
《地球化学》
CAS
1982年第3期322-327,共6页
Geochimica
