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鲁西中生代金岭岩体闪长岩中含有众多的深源捕虏体,主要为纯橄岩和辉石岩.其中纯橄岩又可分为两亚类,一类具板状结构,橄榄石的Mg#值(93-94)高;另一类具变质变形结构,并叠加有矿物反应结构,橄榄石的Mg#值(86-87)低.矿物化学表明前者可能来源于古老的岩石圈地幔,后者曾遭受过富硅钾质熔体的改造.辉石岩中矿物出溶结构的存在、辉石较高的Mg#值以及较高的平均衡温度均暗示该类捕虏体可能为中生代幔源岩浆在上地幔顶部或壳幔边界附近形成的堆积体.
The Mesozoic Jinling pluton in Luxi contains many deep-source xenoliths, mainly dunite and pyroxene, in which dunites can be divided into two subclasses, one with plate-like structure and the other with olive The other is a metamorphic deformed structure with superimposed mineral reaction structure, and the Mg # value of olivine is low (86-87) .Moral chemistry shows that the former probably originated from the ancient rock The latter mantle, which has undergone a transformation of the Si-rich potash melt.The existence of mineral-dissolving structures in pyroxenes, higher Mg # values of pyroxene and higher equilibrium temperatures suggest that these types of xenoliths It may be a sedimentary body formed by the Mesozoic mantle magma at the top of the upper mantle or near the crust and mantle boundary.