Two episodes of orogenic gold mineralization at Chaihulanzi, NE China, in response to superimposed orogeny associated with subduction of the Paleo-Asian and Paleo-Pacific Ocean plates
作者:Lin F. Yang, Qingfei Wang, Zhao Liu, Kexin Zhao, David I. Groves, Chuan Xu, Dong Xu, Wen Li, Zhuang Zhang, Kang Wang, Jun Deng · 发表于:Geological Society of America Bulletin · 年份:2025 · DOI:10.1130/b38071.1 · 被引用次数:6 · 研究领域:Geochemistry and Geologic Mapping、Geochemistry and Geochronology of Asian Mineral Deposits、Geological and Geochemical Analysis
Abstract Detailed structural studies and dating of mineralization define two discrete gold mineralization events during formation of the Chaihulanzi gold deposit. This complexity in gold mineralization resulted from overlap of two distinct orogenic events on the northern margin of the North China Craton. The earlier gold lodes are hosted by NW-SE–trending thrusts and ENE-WSW–trending extensional faults that formed under far-field sub-horizontal NE-SW–trending compression. These lodes comprise pyrite, pyrrhotite, chalcopyrite, sphalerite, tellurides, and native gold associated with quartz-sericite alteration. The later gold veins are controlled by steeply dipping NW-SE– and NE-SW–trending faults that formed under far-field sub-horizontal E-W–trending compression. These veins comprise pyrite, pyrrhotite, and native gold associated with quartz-carbonate or quartz-sericite alteration. The quartz in the earlier and later veins has c-axes with preferred orientations that are sub-parallel and sub-perpendicular to the ore-controlling fault plane, respectively. U-Pb ages of magmatic zircons from the diorite and granite that host later gold ores are dated at ca. 265 Ma. In situ U-Pb dating of hydrothermal rutile and monazite intergrown with gold-bearing pyrite in both earlier and later auriferous quartz veins indicates that the two gold events were at ca. 290 Ma and ca. 170 Ma. These two discrete gold events are related to crustal shortening during subduction of the Paleo-Asian oceanic...