Genesis of Early Paleozoic Adakic Rocks from Dehua Puyang and Pucheng Xianyang in Fujian Province and its Geological Implications
The mechanism of Caledonian orogeny in South China is still controversial.The main argument focuses on the issue that whether there existed Ocean subduction orogeny in the Gallidon period.According to the chronology and geochemical characteristics of monzonitic granites from Puyang granodiorite in Dehua,Fujian Province,and Huangdun and Xianyang in Pucheng,Fujian Province,the rocks have the characteristics of Adakic rocks,and the diagenetic age is 450～455 Ma.Their emplacement time were well corresponding to the subduction stage of the Yunkai orogeny in the southwestern part of Cathaysia block during the Early Paleozoic(460～440 Ma).Combined with the regional data,it is believed that the origin of oceanic subduction plate partial melting,which provides important evidence for the existence of oceanic subduction orogeny in the South China Plate during this period,and indicates that the initial subduction time is no later than 455 Ma.
early Paleozoicadakic rocksoceanic slab subductionCaledonian orogenyzircon U-Pb datingWuyi area
NETL
NSTL
万方数据
