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根据对晚前寒武纪火山岩重新分类结果,原先由Bielski在以色列南部和西奈半岛东北部、由Lenz等人在约旦西南部的个别地点测定年龄(较好的Rb-Sr等时线年龄),主要为535±15Ma至523±9Ma,这是从碱性流纹岩组合取得的。这些可解释为火山作用的年龄,以值得重视的高初始~(8-)Sr/~(86)Sr比值0.7099±0.0013至0.7132±0.0032为特征,它可能混染有地壳物质而形成的。附近的流纹英安岩组合产生含有低初始比值
Based on the reclassification of late Precambrian volcanic rocks, the age (better Rb-Sr isochron age) was previously determined by Bielski in southern Israel and northeastern Sinai, by Lenz et al. At individual sites in southwestern Jordan, Mainly 535 ± 15Ma to 523 ± 9Ma, which is obtained from the combination of alkaline rhyolite. These ages, which can be interpreted as volcanism, are characterized by the high initial ~ (8-) Sr / ~ (86) Sr ratio of 0.7099 ± 0.0013 to 0.7132 ± 0.0032, which may be mixed with crustal matter. The nearby rhyolite dacite assemblages produce low initial ratios