地质通报2018，Vol.37Issue(5)：895-907,13.
桂东北苗儿山张家花岗岩LA-ICP-MS锆石U-Pb年龄与地球化学特征
Geochronology and geochemistry of the Zhangjia granitic pluton in the Miaoershan uranium orefield, Northeastern Guangxi Province
摘要
Abstract
Two samples were collected near the Zhagutian uranium ore deposit and Zhangjia uranium ore deposit respectively to carry out LA-ICP-MS zircon U-Pb isotopic dating.The analytical result demonstrates that the formation age of the host rock in the Zhagutian uranium ore district is 218.0±1.4Ma,whereas the formation age of the host rock in the Zhangjia uranium ore district is 226.8±5.7Ma.Furthermore,the Zhangjia granite is characterized by high SiO2 (74.35％～76.29％),Al2O3 (12.54％～14.03％) and (Na2O+K2O) (6.95％～9.17％),but low MgO (0.34％～0.45％),CaO (0.68％～1.03％) and TiO2 (0.106％～0.18％),so it belongs to high-K calc-alkaline series granite.The Zhangjia granite is rich in Rb,and poor in Ba,Sr with high Rb/Sr ratio,so it belongs to low Ba-Sr granite series.The granite is rich in LREEs with negative Eu anomalies.Meanwhile,The granite is rich in U(21.5×10-6 on average) with low Th/U ratio (1.63 on average),so it is very favourable for uranium mineralization.The granite has high (87Sr/86Sr),(～0.7247),low εNd(t) (-13.95 on average) and its two-stage Nd isotopic model ages are (2.07～2.19Ga).The Zhangjia granite belongs to strongly peralurninous S-type granite.It probably originated from partial melting of Proterozoic sedimentary metamorphic rocks.关键词
产铀岩体/LA-ICP-MS锆石U-Pb年龄/地球化学/张家花岗岩Key words
U-bearing granite/LA-ICP-MS zircon U-Pb age/geochemistry/Zhangjia granitic pluton分类
天文与地球科学引用本文复制引用
王正庆,范洪海,陈东欢,谢财富,肖为,罗桥花,郑可志,管太阳,林子瑜..桂东北苗儿山张家花岗岩LA-ICP-MS锆石U-Pb年龄与地球化学特征[J].地质通报,2018,37(5):895-907,13.基金项目
中核集团项目《南方重点花岗岩型铀矿基地资源预测和扩大》和中国地质调查局项目《整装勘查区找矿预测与技术应用示范》(编号:12120114052401) （编号:12120114052401）
