地质通报2016，Vol.35Issue(8)：1291-1303,13.
桂东南大容山晚二叠世花岗岩锆石U-Pb年龄和Sr-Nd-Hf同位素特征及其地质意义
Late Triassic zircon U-Pb ages and Sr-Nd-Hf isotopes of Darongshan gran- ites in southeastern Guangxi and their geological implications
摘要
Abstract
The petrogenesis and geodynamic processes of the Darongshan granite have been a subject of much controversy. In this paper, the authors report U-Pb ages and Sr-Nd-Hf isotopes for the Darongshan granite in southeastern Guangxi. LA-ICP-MS U-Pb zircon analysis yielded 206Pb/238U weighted mean age of 253.6±2.1Ma, 256.4±1.8Ma and 256.8±2.8Ma for three granite sam⁃ples respectively, indicating that these granites are of Late Permian origin rather than the Early-Middle Triassic origin. They have relatively high εNd(t) values (-9.18~-13.4) and younger Nd model ages (tDMc=1.55~1.84Ga), which are consistent with εHf(t) val⁃ues (-5.5~-6.7) and Hf model ages (TDM2=1.64~1.71Ga), suggesting an lower crustal source mixed with the Paleo-Mesoproterozoic materials. Combined with previous studies, the authors hold that the Darongshan granitic magmatism might have been related to anatexis of the lower crust due to the subduction/collision between Indosinian block and South China plate during the Hercynian to Indosinian period.关键词
锆石U-Pb/Sr-Nd-Hf同位素/花岗岩/大容山/桂东南地区Key words
zircon U-Pb/Sr-Nd-Hf isotope/granite/Darongshan/southeastern Guangxi分类
天文与地球科学引用本文复制引用
王磊,龙文国,周岱,徐旺春,金鑫镖..桂东南大容山晚二叠世花岗岩锆石U-Pb年龄和Sr-Nd-Hf同位素特征及其地质意义[J].地质通报,2016,35(8):1291-1303,13.基金项目
中国地质调查局项目（编号1212011085416、12120113063000）和国家自然科学基金项目 （）
