1. 合肥工业大学资源与环境工程学院 合肥 230009;
2. Centre of Excellence in Ore Deposit(CODES), University of Tasmania Private Bag 79, Hobart, Australia
Diagenetic age of the intrusions in southern part of the Lu-Zong Basin and its significance
Fan Yu1, Qiu Hong1, Zhang Lejun1,2
1. School of Resources and Environmental Engineering, Hefei University of Technology, Hefei 230009;
2. Centre of Excellence in Ore Deposit(CODES), University of Tasmania, Private Bag 79, Hobart, Australia
Abstract：
LA-ICP MS zircon U-Pb dating for the hidden intrusions: such as Shadun intrusion, Chuanshaoshi intrusion, Qingshan intrusion, Hejiaao intrusion, Meilin intrusion, Gutangchong intrusion, Zhoujiashan intrusion in the south of the Lu-Zong Basin was carried out in this paper. These intrusions consist of alkali-feldspar granite and quartz syenite which contain a lot of K-feldspar. LA-ICP MS zircon U-Pb dating yields the ages of 126.5±1.1 Ma, 126.2±1.2 Ma、126.7±1.3 Ma, 126.9±1.4 Ma, 125.9±1.3 Ma, 126.7±1.4 Ma, 124.9±1.3 Ma for five intrusions, respectively. The results indicate that all the hidden intrusions in the south of Lu-Zong Basin formed in the Early Cretaceous. These intrusions are characterized by relative high silica and alkalis, ascribed to metaluminous or peraluminous, moderate REE and strong Eu depletion with a slightly right-inclined sea-gull REE patterns. These data, together with other accuracy dating data of volcanic rocks and intermediate-acid high-K calc-alkalic plutons in the middle and lower reaches of the Yangtze River area, support the intrusions formed in a within-plate tensional tectonic environment. The results of the study are important for discussing the geodynamic settings of these intrusions in the middle and lower reaches of the Yangtze River area.
2014, Vol. 49 
