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对美国亚利桑那州50个矿床的矿石研究表明,铅同位素组分和Th/U比模式(根据亚利桑那州的地壳形成年龄170Ma),按~(208)Pb/~(204)Pb与~(206)Pb/~(204)Pb关系图可分为3组。此图可借助美国西南部下元古界的全岩分析结果来模似区域铅同位素的变化趋势。根据下元古界全岩(和矿石)分析可以确定出富银矿和富金矿的地壳成矿省的情况。亚利桑那州西部和Mojave西部:Th/U>4;亚利桑那州中部:Th/U 2和亚利桑那州东南部:Th/U 4。
Ore studies on 50 deposits in the United States of Arizona in the United States showed that the Pb isotopic composition and Th / U ratio (~ 208 Pb / 204 Pb) and ~ (206) Pb isotopes and Th / U ratios (based on the crustal age 170 Ma in Arizona) Pb / ~ (204) Pb can be divided into three groups. This map can be used to simulate the trend of Pb isotope variation in the region with the help of the rock analysis results of the Lower Proterozoic in the southwestern United States. Based on the analysis of the whole Lower Proterozoic whole rock (and ore), we can determine the crustal metallogenic province of rich silver and gold-rich ore. Western Arizona and western Mojave: Th / U> 4; Central Arizona: Th / U 2 and southeastern Arizona: Th / U 4.