关键词: 德化－尤溪－永泰矿集区, 基底构造格局, 破火山口, 推覆－滑覆复合构造, 金铜成矿系统

Abstract: The Wuyishan metallogenic belt exists widespread Mesozoic epithermal-porphyry gold-copper metallogenic system, where mineralization closely related to ancient basement and volcanism. The composite ore-controlling of basement tectonics and volcanic structure is not enough understood. This paper reviews recent advances on Neoproterozoic-early Paleozoic basement rocks and their tectonic attributes, as well as Mesozoic volcanism-metallogeny in the Wuyishan metallogenic belt, and then focuses on the basement and caldera of the Dexi-Yixi-Yongtai ore concentration area in central Fujian Province. The results show that multi-stage Au-Cu mineralizations in the study area were jointly controlled by basement and volcanic structures. The basement is dominated by Neoproterozoic accretionary complexes and Early Paleozoic intrusions, which made up large composite thrust-gliding nappe system in mid-late Jurassic (170-168 Ma). The Leitan caldera is identified as the most completely preserved mid-late Jurassic caldera in South China, and spatially outward, its diagenesis and mineralization become younger from middle to late Jurassic, with epithermal Au- Cu deposits transitioning from intermediate- to low- sulfidation. This study can provide valuable insights for tectonic evolution and ore prospecting in volcanic areas of the belt.

Key words: Dehua-Youxi-Yongtai ore concentration area, basement tectonics, caldera, thrust-gliding nappe system, gold-copper
metallogenic system