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本文研究的闽西南地区晚中生代花岗质岩体中莒舟花岗岩体单颗粒锆石U-Pb年龄为136．0Ma,133．9Ma,黑云母Ar-~(39)Ar年龄为132．3Ma,菜刀岐石英斑岩单颗粒锆石U-Pb年龄为117．4Ma,太华花岗岩体全岩Rb-Sr年龄为114．9Ma,都属早白垩世。莒舟花岗岩富Si、K、Rb-Th,Y含量高,铝弱过饱和,贫Sr、Ba、P、Ti、Eu,过渡元素显著亏损而具壳源型花岗岩特征,菜刀岐石英斑岩是其高程度分异演化的产物,并为锡矿床的形成提供了物质基础。莒舟岩体是在岩石圈伸展的底侵作用下所形成的,岩石中有少量幔源组分加入,岩石的ε_(Nd)(t)偏低(-7．21),t_(DM)偏高(1．52Ga)。太华花岗岩体的ε_(Nd)(t)稍高(-3．60～-3．68),t_(DM)稍低(1．21Ga),岩石中有较多幔源组分加入,是壳幔混合源花岗岩。过铝质壳源型花岗岩可以在与岩石圈伸展作用相关的张性构造环境中形成,壳幔相互作用对锡矿床的形成具有重要的贡献。
The zircon U-Pb ages of the Qiongzhou granite in the Late Mesozoic granitic rocks in the southwestern Fujian Province are 136.0Ma and 133.9Ma, and the Ar- 39Ar ages of the biotite are 132.3Ma. The U-Pb age of the single-particle zircon of the Chikui quartz porphyry is 117.4Ma, and the Rb-Sr age of the whole rock of the Taihua granite is 114.9Ma, both belonging to the Early Cretaceous. Si Zhou granite rich in Si, K, Rb-Th, Y content is high, weakly supersaturated aluminum, depleted in Sr, Ba, P, Ti, Eu significant loss of transitional elements with shell-sourced granite features, Its high degree of differentiation and evolution of the product, and for the formation of the tin deposit provides a material basis. The rock mass is formed under the outcrop of lithosphere extension. A small amount of mantle source components are added into the rock. The ε_ (Nd) (t) of the rock is low (-7.21), t_ (DM) High (1.52Ga). The ε_ (Nd) (t) of Taihua granite body is slightly higher (-3.60 ~ -3.68) and the t_ (DM) is slightly lower (1.21Ga), and more mantle source components are added in the rocks, Crust mixed mantle source granite. Pergoloid crust-derived granites can be formed in an extensional tectonic setting associated with lithospheric extension, and crust-mantle interaction plays an important role in the formation of the tin deposit.