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本文讨论了大兴安岭由于中生代底侵作用形成的两种类型的陆壳增生方式： １） 来自地壳底部壳幔混源岩浆房的花岗岩和火山岩对上部陆壳的增生， 岩浆的侵位和喷发集中在１４５～１１５ Ｍａ， 它们具明显的幔源岩石同位素特征， 如正的εＮｄ （ｔ）值（０～４），低的８７Ｓｒ／８６ Ｓｒ 初始比值（０．７０４～０．７０８）等； ２）早中生代形成的镁铁－超镁铁质堆晶岩（２４１～２１４ Ｍａ）对下部陆壳的增生。
In this paper, we discuss two types of continental crust hyperplasia caused by the Mesozoic underplating in the Greater Hinggan Mountains: 1) granite and volcanic rocks from the crust-mantle mixed-source magmatic chamber at the bottom of the crust are responsible for the uplifting of the upper continental crust, emplacement and eruption of magma 145 ~ 115 Ma, which have obvious isotopic characteristics of mantle source rocks, such as positive εNd (t) values (0-4) and low initial 87Sr / 86 Sr ratios (0.704-0.708) Early Mesozoic formation of mafic-ultramafonic pluton (241 ~ 214 Ma) on the lower continental crustal hyperplasia.