Geology of the Fuding inlier in Southeastern China: implication for late Paleozoic Cathaysian paleogeography

The age and composition of the basement rocks underlying the Mesozoic volcanic rocks in southeastern China have been long debated. New field investigation, stratigraphical and sedimentological studies of the Fuding inlier in eastern Cathaysian block have identified the presence of three stratigraphic units. The Upper Carboniferous carbonate unit, composed of silicified limestone, deposited on carbonate platform in a continental shelf environment. The Lower Permian siliciclastic unit, consisting of slate and phyllite with minor arenites, deposited on shallow semi-restricted shelf. The third unit is a suite of Jurassic conglomerates and sandstones deposited in alluvial fan environment. Provenance data indicate that the Fuding inlier was part of the Wuyishan terrane in the eastern Cathaysian block. The U-Pb age and Hf isotope of detrital zircons indicate that extensive magmatic activity happened during 280-360Ma in the source area. The ε _Hf values of detrital zircons point to magmatic mixing of juvenile material and Precambrian crust. The similarities in rock compositions and detrital zircon ages among the Yeongnam massif in the Korean Peninsula, the Tananao complex in Taiwan and the Fuding inlier have led to the conclusion that these three regions most likely belonged to the Wuyishan terrane, eastern Cathaysia during the late Paleozoic.