Zircon U-Pb Dating,Tectonic Setting and Ore-bearing Properties Evaluation of the Caledonian Yangbu Pluton in South Jiangxi

The Yangbu pluton is one of the famous Rare earth element granitoid plutons in South Jiangxi,but it lacks precise isotopic chronological data.In this paper,we present research for the zircon U-Pb chronology of the Yangbu pluton by using Laser Ablation-Multicollector Inductively Coupled Plasma-Mass Spectrometry(LA-MC-ICPMS).The yield weighted average 206Pb/238U age is(461.1±1.3) Ma,which illustrates that the Yangbu pluton formed in the Middle Ordovician period.Granitic plutons,Yangbu,Shanzhuang(in the Wugong Mountains),Shangyou(in South Jiangxi) and Yunkai Mountain,have the same zircon U-Pb ages,which are products of the first peak period of magmatism during the Late Caledonian period in southern China,indicating a new cycle of folding and orogeny.Geochemical dates of Caledonian granitoids in Jiangxi Province show that most of them with higher ∑REEs content have a major necessary condition of mineralization mother rock of weathered-crust type REEs deposits.Therefore,they should be considered during ore-bearing properties evaluation and ore prospecting.