LA-ICP-MS zircon U-Pb dating and geological features of Changxing intrusion in the Hebaoshan gold deposit, Taining County, Fujian Province

Abstract: The Changxing potash feldspar migmatitic granite is related to the mineralization in the Hebaoshan gold deposit. The mineralization in the Hebaoshan gold deposit shows multi-period and multi-stage characteristics, and the intrusion activities of Changxing potash feldspar migmatitic granite in the late Caledonian promoted the?early?period migration and enrichment of the ore-forming elements in the gold deposit and the tectonic-magmatic activity of the late Indosinian to early Yanshanian superimposed mineralization. The authors made a detailed chronological study of the main intrusive rocks formed in the Caledonian period. In-situ zircon U-Pb dating was performed with LA?ICP?MS, and reliable n(206Pb)/n(238U) age data of zircons were obtained. The results yielded concordant age of (437.1±1.3) Ma for potash feldspar migmatitic granite, (436.6±1.1) Ma for biotite quartz diorite and (427.1±1.4) Ma for biotite granite diorite vein. The age data constrain the upper limitation of the metallogenic period, thus having great geological implications for further mineralization research.