稀有气体同位素示踪成矿古流体研究进展

ADVANCES IN TRACING THE ORE-FORMING FLUIDS USING RARE GAS ISOTOPES

稀有气体(特别是He、Ar)是一种研究成矿古流体来源的灵敏示踪剂。地球不同圈层的稀有气体同位素具有不同的特征同位素比值。测试样品流体包裹体中的稀有气体同位素值,从测试值中排除掉包裹体形成后各种后生过程对流体初始同位素组成的影响。把得到的结果与前人研究总结的特征值进行比较分析,可以示踪成矿流体来源,从而探讨各种矿床的成矿机制与成矿作用。归纳了近年来用稀有气体同位素来示踪成矿流体的研究进展,概括了其在不同类型矿床中的应用现状,并指出当前该方法存在的问题及发展趋势。

Rare gas isotopes, especially helium and argon isotopes, are sensitive to trace the origin of the ancient ore-forming fluids. Rare gases in different spheres of the earth have different characteristic isotopic ratios. The rare gas isotopic ratio in the fluid inclusions of the samples is determined, and the influence caused by all kinds of latter processes from the measured data is ruled out. Comparing the above result with the characteristic values in different reservoirs in Earth, we can trace the origin of ore-forming fluids and further discuss the mineralization mechanism for some deposits. The progresses of tracing ore-forming fluids in different kinds of ore deposits using rare gas isotopes are summarized, and some problems and the developing tendency about this method are also discussed.