Geochronology of the Diorite Porphyrites in
详细信息
- 责任者：Fan Yu (School of Resources and Environmental Engineering ; Hefei University of Technology ; Hefei 230009 ; China) ; Zhou Taofa
- 刊名：Acta Petrologica Sinica
- 出版年：2010
- 卷期：26(9)
- 关键词：玢岩铁矿床 ; porphyrite iron deposit ; 闪长玢岩 ; diorite porphyry ; 安徽 ; Anhui Province ; 江苏 ; Jiangsu Province
- 页码：p.2715-2728
- 图表：6 illus., 1 table, 78 refs.
- 分类号：0801
- issnNo：ISSN1000-0569
- isbnNo：CN11-1922/P
摘要
Based on detailed field geological work, the authors carried out systematic geochronological study of diorite porphyrite plutons related to porphyry-like type iron deposits in Ning-Wu Basin. LA-ICP-MS zircon U-Pb dating for seven diorite porphyrite plutons such as Washan, Taocun, Heshangqiao, Dongshan, Baixiangshan, Hemushan and Gushan intrusions, has been carried out. LA-ICP-MS zircon U-Pb dating yield the ages of 130.2±2.0 Ma, 130.7±1.8 Ma, 131.1±1.5 Ma, 131.1±3.1 Ma, 130.0±1.4 Ma, 131.1±1.9 Ma and 129.2±1.7 Ma for intrusions, respectively. The dating result indicates that different diorite porphyrite plutons in Ning-Wu volcanic basin are all formed in the early stage of Early Cretaceous about 130 Ma, which can nearly represent the metallogenetic epoch of the porphyry-like type iron deposits. There are three periods（145~136 Ma, 135~127 Ma, 126~123 Ma）of ore-forming and magmatic activity in the Middle-Lower Yangtze River Valley metallogenic belt. The diorite porphyrite plutons in Ning-Wu basin were the products of the second period magmatic activity and obviously later than the high-k calc-alkaline intrusions related to skarn-porphyry Cu-Au deposits in uplift areas in the Middle-Lower Yangtze River Valley metallogenic belt.