Dating of copper mineralization in Jingbian deposit and its prospecting significance in Luzong basin, Anhui Province.
安徽庐枞盆地井边铜矿床的成矿时代及其找矿指示意义

Luzong basin is one of the most important metallogenic district in the mineralization belt of the Middle and Lower Reaches of the Yangtze River area, where occurs many vein-type copper deposits with various scales. Nevertheless, little research work has been done on the timing and tectonic setting of these deposits. In this paper we present the LA-ICP-MS zircon U-Pb dating results of andesite porphyry and fluid inclusions Ar-Ar dating results of quartz from Jingbian vein-type copper deposit. LA-ICP-MS zircon U-Pb dating yield the age of 133.2±1.7Ma, and fluid inclusions in quartz yield an isochronal age of 133.3±8.3Ma and an inverse isochronal age of 133.3±8.2Ma respectively. These results coincident with the geological characteristics of deposits and the available highly precise dating of related magmatic rocks. So the Jingbian vein-type copper deposit took place in Early Cretaceous and related to the intrusive activity of Zhuanqiao Formation. This mineralization event in Luzong basin were consistent with the second period (135~127Ma) magmatic and metallogenic activity in the Middle and Lower Reaches of the Yangtze River area, and corresponding to an extension tectonic environment. This contribution is not only providing evidence for a comprehensive understanding the magnetism and mineralization of the Luzong basin, but also shows the prospecting potential to find cooper deposit in this area.