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湘南早白垩世（１３２～１３５）Ｍａ基性火山岩中含有橄榄岩类、辉长岩类、角闪麻粒岩相酸性岩包体，这三类包体的岩石学特征及地球物理参数（ｖｐ，ρ），分别与岩石圈地球物理模型中的上地幔，下地壳及中地壳相吻合。包体的岩相学、主要元素、ＲＥＥ及稀有元素地球化学特征及同位素年龄的研究结果表明，现在的岩石圈中的下地壳部分是元古代（１１４１Ｍａ±６７Ｍａ）由底板垫托垂直增生形成的；中地壳与世界范围内的中地壳和中国华北及扬子克拉通相比偏酸性，而下地壳则偏基性，以富Ａｌ２Ｏ３为其特征。这一富Ａｌ２Ｏ３的下地壳包体除了在美国亚利桑那以外，在世界范围内还未曾见过报道。
The Late Cretaceous (132 ~ 135) Ma basic volcanic rocks in Hunan Province contain peridotites, gabbro and hornblende magmatism acidic rock inclusions. The petrological characteristics and geophysical parameters (vp , Ρ) coincide with the upper mantle, the lower crust and the middle crust in the lithosphere geophysical model respectively. The lithofacies, major elements, REE, geochemistry of rare earth elements and age of isotopes indicate that the lower crust in the lithosphere is formed by vertical accretion of the Proterozoic (1141Ma ± 67Ma) . The middle crust is more acidic than the world-wide crust and North China and Yangtze craton in China, while the lower crust is more alkaline and rich in Al2O3. This Al2O3-rich lower crust enclave has not been reported in the world except Arizona in the United States.