LA-ICP-MS Zircon U-Pb Dating and its Geological Implications of the Middle-high Grade Metamorphic Rocks in the Diaoluoshan Area,Southeastern Hainan Island
LI Sunxiong;WEI Changxin;WANG Yanhua;HU Zailong;CHEN Fangying;Hainan Institute of Geological Survey;
The mesometamorphic rocks in the Diaoluoshan area are composed of granulite and gneiss occurring as discrete patches in the Permian granite. Based on lithological comparison, the metamorphic rocks were classified as the Mesoproterozoic Baoban Group in the previous literatures. Our LA-ICP-MS zircon U-Pb results of the granulite and gneiss yielded ages of 255?9 Ma and 247?8 Ma, respectively. The zircon U-Pb ages of the metamorphic rocks demonstrated that the metamorphism of the rocks took place in Hercynian-Indo-Chinese Epoch rather than the previously believed Mesoproterozoic Period.