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

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.