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东南沿海地区新生代玄武岩中的橄榄岩包体来自岩石圈地幔 ,上地幔橄榄岩包体的岩石学及地球化学特征都记录了地幔演化的历史。普宁橄榄岩包体斜方辉石含量与太古宙克拉通地幔类似 ,但在矿物学、REE、痕量元素和Sr Nd同位素上又与太古宙岩石圈地幔不同。橄榄岩包体的岩相学、矿物学、REE、痕量元素特征都提供了含H2 O富Si流体交代橄榄岩的证据 ,这种流体可能主要是洋壳物质局部熔融而成。流体交代使橄榄岩富Si,同时富Sr、Pb和强不相容元素等大洋岩石圈物质。这表明普宁大陆岩石圈地幔既保留太古宙岩石圈地幔的特征 ,又具有大洋俯冲地幔的特征 ,它是古老岩石圈地幔向大洋岩石圈地幔转换的一部分 ,这种转换可能是大洋岩石圈与大陆岩石圈地幔相互作用的结果。
Peridotectonic inclusions in the Cenozoic basalts in the southeastern coastal region are derived from lithospheric mantle. The petrological and geochemical characteristics of the upper mantle peridotite enclose the history of mantle evolution. The Peridot ophiolite inclusions are similar to the Archean cratonic mantle except for the Archean lithospheric mantle in mineralogy, REE, trace elements and Sr-Nd isotopes. The petrographic, mineralogical, REE, and trace element characteristics of peridotite inclusions provide evidence of the substitution of perovskite-rich fluids with perovskite-type hydrothermal H 2 O. This fluid probably consists of locally melted oceanic crustal material. The fluids account for the enrichment of peridotites with Si, while being rich in Sr, Pb and strongly incompatible elements such as oceanic lithosphere material. This shows that the Puning continental lithospheric mantle not only retains the characteristics of the Archean lithospheric mantle, but also has the characteristics of ocean subduction mantle, which is part of the transition from the ancient lithospheric mantle to the oceanic lithospheric mantle, which may be the result of the interaction between the oceanic lithosphere and the mainland Lithospheric mantle interaction results.