The tectonic setting of the Early Paleozoic granites in the South China Block (SCB) remains enigmatic, and it is uncertain as to whether they are related to intracontinental orogenic processes or oceanic subduction. Previous studies mostly focused on Early Paleozoic S–type granitoids in the SCB, and relatively little attention has been paid to Early Paleozoic I–type granitoids. Here we present whole–rock major and trace elemental data and LA–ICP–MS zircon U–Pb age and Lu–Hf isotopic data for hornblende monzogranites, monzogranites, and mylonitic granites of I–type granites affinities that comprise the Daning and Guiling plutons in the southwest part of the Wuyi–Yunkai orogen in the SCB. These rocks contain zircon with U–Pb ages of 422–418 Ma, taken as the age of emplacement. They are rich in LREEs and moderately depleted in Eu (δEu = 0.49–0.64), with negative Ba, Sr, Nb, and Ti anomalies, and positive in Rb, Th, U, and Pb anomalies. Our studies of these granites and their abundant enclaves indicate that they formed via complicated petrogenetic processes, including the partial melting of a mixed source of meta–sedimentary rocks and meta–basalts in the lower crust, magma mingling and mixing of crust–mantle materials, and fractional crystallization. Mantle–derived magma played an important role in the formation of these Early Paleozoic granites. Although an ancient and enriched mantle source might have made a significant contribution to these Early Paleozoic granites, the input of juvenile mantle–derived magma might have been insignificant. Taking into account all the other geological evidence from the Wuyi–Yunkai region, we suggest that the tectono–magmatic events of the Early Paleozoic took place during intraplate orogenesis rather than oceanic subduction and collision, and that these events were triggered by a far–field tectonic response to the assembly of northern East Gondwana.

华南地块（SCB）早古生代花岗岩的构造环境仍是一个谜，是否与陆内造山过程或大洋俯冲有关尚不确定。以往的研究主要集中在SCB中的早古生代S型花岗岩，而对早古生代I型花岗岩的关注相对较少。在这里，我们提供了包含大宁和桂陵岩体的角闪石二长花岗岩、二长花岗岩和糜棱花岗岩的全岩主量和微量元素数据以及 LA-ICP-MS 锆石 U-Pb 年龄和 Lu-Hf 同位素数据位于南海区武夷-云开造山带西南部。这些岩石中含有锆石，U-Pb 年龄为 422-418 Ma，作为侵位年龄。它们富含轻稀土元素并适度消耗 Eu (δEu = 0.49–0.64)，Ba、Sr、Nb 和 Ti 异常为负，Rb、Th、U 和 Pb 异常为正。我们对这些花岗岩及其丰富的飞地的研究表明，它们是通过复杂的岩石成因过程形成的，包括下地壳变质沉积岩和变质玄武岩混合源的部分熔融，岩浆混合和壳幔物质的混合，和分步结晶。地幔源岩浆在这些早古生代花岗岩的形成中发挥了重要作用。尽管古老而富集的地幔源可能对这些早古生代花岗岩做出了重大贡献，但来自年轻地幔的岩浆的输入可能微不足道。考虑到武夷-云开地区的所有其他地质证据，