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我们试验了一种Rb-Sr法,它可以利用象方解石和萤石那样的常见脉石矿物测定矿床的年龄。矿床必须满足的条件只有两条:1)有低Rb/Sr比值的矿物;2)被有高Rb/Sr比值的围岩包围着。因为热液矿物获得的锶同位素组成通常与围岩相似,具有低Rb/Sr比值的矿物应当把围岩在矿化期间具有的同位素组成记录并保存下来。该Rb/Sr比值与现在围岩的Rb/Sr
We tested a Rb-Sr method that can determine the age of a deposit using common gangue minerals such as calcite and fluorite. The deposit must meet only two conditions: 1) a mineral with a low Rb / Sr ratio; and 2) surrounded by a wall rock with a high Rb / Sr ratio. Because the strontium isotopic compositions obtained by hydrothermal minerals are generally similar to those of the surrounding rocks, minerals with a low Rb / Sr ratio should record and preserve the isotopic composition of the surrounding rock during mineralization. The Rb / Sr ratio is now related to the Rb / Sr of the surrounding rock