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最近十年的研究成果令人信服地证明了地球上地幔的同位素的不均匀性。已能够拟定一些方法,用来确定具有一定特征的地幔“块段”的规模及这些“块段”在纵向和横向的分布。发表了对一些事件年代的估算结果,这些事件乃是壳下带同位素不均匀性的原因。关于上地幔不均匀的思想也在稀有和分散元素方面发展着。业已证明,富含Rb-Sr Sm-Nd,U-Th-Ph 系列放射性同位素的地幔块段,通常其特征是稀有亲石元素的浓度增高。推测上
The results of the last ten years have convincingly demonstrated the isotopic heterogeneity of the Earth’s mantle. It has been possible to devise methods for determining the size of the “block” of mantle with certain characteristics and the distribution of these “blocks” in the longitudinal and transverse directions. Published estimates of the age of events that are responsible for the heterogeneity of the isotopes beneath the crust. The idea of unevenness in the upper mantle has also developed in rare and scattered elements. It has been shown that mantle blocks rich in Rb-Sr Sm-Nd and U-Th-Ph series of radioisotopes are often characterized by increased concentrations of rare lithophile elements. Speculated on