矿床地质2011，Vol.30Issue(2)：349-360,12.
西藏邦铺钼(铜)矿床含矿二长花岗斑岩LA-ICP-MS锆石U-Pb定年及地质意义
LA-ICP-MS zircon U-Pb dating of ore-bearing monzogranite porphyry in Bangpu molybdenum (copper) deposit, Tibet and its significance
摘要
Abstract
The Bangpu porphyry Mo (Cu) deposit is located about 30 km northeast of the Jiama copper polymetallic deposit. The rocks related to molybdenum mineralization in this ore deposit are mainly monzogrante porphyry,with minor granodiorite porphyry and diorite (porphyrite). The age of the ore-forming rock was obtained through LA-ICP-MS precise determination of the zircon U-Ph age for the molybdenite-bearing monzogranite porphyry. 26 zircons from the monzogranite porphyry yielded the weighted average 206pb/238U age of ( 16.23 ±0.19) Ma (MSWD= 2.0, n = 26), suggesting Miocene granitic magma emplacement in the Gangdese belt.The previous dating of the molybdenite from this ore deposit had yielded a Re-Os isochron age of (15.32 ± 0.79)Ma, which is about 1 Ma later than the time of rock cooling. Thus the authors' work has improved the constraint of mineralization in time. Regional minerogenetic regularity shows that the Bangpu porphyry Mo (Cu)polymetallic deposit has an uniformity with the regional porphyry-skarn deposits (such as Jiama, Qulong and other ore deposit in this region) in the age of petrogenesis and mineralization, which shows that this ore deposit has the same tectonic and magrnic geochemical dynamic background as other ore deposits in this region, and that this ore deposit was a product of mineralization explosion during the extension phase after India-Asia continental collision.关键词
地球化学/LA-ICP-MS/锆石U-Pb定年/二长花岗斑岩/邦铺/冈底斯/西藏Key words
geochenistry/ LA-ICP-MS/ zircon U-Pb dating/ monzogrsnite porphyry/ Bangpu/ Gangdese/ Tibet分类
天文与地球科学引用本文复制引用
王立强,唐菊兴,陈毓川,罗茂澄,冷秋锋,陈伟,王焕..西藏邦铺钼(铜)矿床含矿二长花岗斑岩LA-ICP-MS锆石U-Pb定年及地质意义[J].矿床地质,2011,30(2):349-360,12.基金项目
本文为国家基础研究计划"973"项目(2011CB403103)、国土资源部公益性行业科研专项(200911007-02)和中国地质调查局青藏高原专项(1212010012005)共同资助的成果 （2011CB403103）
