- 责任者：Wang Yuli (School of Earth Sciences ; Jilin University ; Changchun 130061 ; China) ; Sun Fengyue
- 刊名：Geology and Resources
- 出版年：2013
- 卷期：22(2)
- 关键词：铁矿 ; iron ores ; 铀—铅计时 ; U-Pb dating ; 新疆 ; Xinjiang
- 页码：p.114-119,137
- 图表：illus., 2 tables, 20 refs.
- 分类号：1001
- issnNo：ISSN1671-1947
- isbnNo：CN21-1458/P
The Mengku iron deposit in Fuyun County,Xinjiang is located in the Maizi volcanic-sedimentary basin along the southern margin of Altai metallogenic belt.Its main ore bodies are genetically of volcanism-related hydrothermal spout sedimentation type.The ore bodies occur mainly in Kangbutiebao Formation with leucogranulite,granulitite and amphibolite.The protolith recovery displays marine volcanic rocks of mainly spilite-keratophyre and quartz keratophyre,with minus rhyolite-tuff.The sedimentary rocks involve calcareous tuffaceous sandstone intercalated with crystalline limestone.By zircon LA-ICP-MS U-Pb dating of the leucogranulite in Mengku iron deposit,the age of Kangbutiebao Formation and the deposit is defined.The contents of Th range from 29.5×10^-6-82.7×10^-6 to 32.1×10^-6-109.3×10^-6;while of U,from 35.7×10^-6-132.1×10^-6to 47.6×10^-6-140.6×10^-6,with Th/U ratio between 0.41-1.19 and 0.51-0.85,showing typical features of magmatic zircons.The zircon ages of the leucogranulite in Mengku deposit are 397.5±2.5 Ma and 389.0±4.7 Ma.Combined with regional geochronological data,it is concluded that the Kangbutiebao Formation was formed in the Early Devonian,with a ceiling age of 389±4.7 Ma.The main ore bodies of the deposit are dated at 397.5±2.5 Ma.