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(三)关于大陆岩浆岩地球化学特征的结论在第(二)部分中指出,大陆壳的主要部分来源于沿俯冲带下插的大洋壳。这部分的目的是,从这一认识出发,推导出“原生”大陆岩浆岩特征的同位素地球化学和元素地球化学判据,从而为可靠区分原生的岩浆岩及次生演变的和再生的岩浆岩创造前提,并为解释这种次生演变(包括有关矿床成因)作出贡献。进行本项研究的一个重要动机在于,区分原生岩浆岩和其他成因岩浆岩的常用判据,即有关岩石中的~(67)Sr/~(86)Sr、~(143)Nd/~(144)Nd 和请下载后查看，本文暂不支持在线获取查看简介。(208)Pb/~(204)Pb 初始比值与上地幔中相应比值的对比,只是对于一些年青岩浆岩才较为可靠。
(III) Conclusions on the Geochemical Characteristics of Continental Magmatic Rocks In part (b), it is pointed out that the major part of the continental crust originates from the oceanic crust inserted along the subduction zone. The purpose of this section is to derive from this understanding the isotope geochemical and elemental geochemical criteria for “native” continental magmatic rocks to provide reliable discrimination between primary magmatic rocks and secondary evolved and regenerated magmatic rocks Create the premises and contribute to explain this secondary evolution (including the cause of the deposit). An important motivation for carrying out this study lies in the common criteria for distinguishing primary magmatic rocks from other genetic magmatic rocks, namely, ~ (67) Sr / ~ (86) Sr, ~ (143) Nd / ~ ) Nd and Please download to view, this article does not support online view profile. (208) The initial ratio of Pb / ~ (204) Pb to the corresponding ratio in the upper mantle is only reliable for some young magmatic rocks.