Geochronology and Its Geological Implications of LA-ICP-MS Zircon U-Pb Dating of Granodiorite Porphyries in Dabaoshan Polymetallic Ore Deposit,North Guangdong Province

• 责任者：Wang Lei (Faculty of Earth Resources ; China University of Geosciences ; Wuhan 430074 ; China) ; Hu Mingan
• 刊名：Earth Science
• 出版年：2010
• 卷期：35(2)
• 关键词：花岗闪长斑岩 ; granodiorite porphyry ; 铀—铅计时 ; U-Pb dating ; 广东 ; Guangdong Province
• 页码：p.175-185
• 图表：3 illus., 2 tables, 44 refs.
• 分类号：0801
• issnNo：ISSN1000-2383
• isbnNo：CN42-1233/P

The dating of LA-ICP-MS zircon U-Pb was carried out for granodiorite porphyries at Dabaoshan polymetallic ore deposit in North Guangdong Province. In cathodoluminescence (CL) image, most zircons in two granodiorite porphyry samples exhibit oscillatory zoning, which is typical for magmatic zircon. The dating of LA-ICP-MS zircon U-Pb of two samples shows the results that 12 points of oscillatory zoned domains of Dabaoshan granodiorite porphyry sample yields a group of weighted mean ²⁰⁶Pb/²³⁸U ages at (175.8±1.5) Ma (MSWD=0.037) and 16 points of oscillatory zoned domains of Chuandu granodiorite porphyry yields a group of weighted mean ²⁰⁶Pb/²³⁸U ages at (175.0±1.7) Ma (MSWD=0.41). So the epoch of granodiorite porphyry emplacement is nearly 175 Ma, belonging to the first stage of the early Yanshanian (180~170 Ma).