摘要
唐家沟金矿床是胶东地区牟平-乳山金矿带内一典型石英脉型金矿床。矿体产出于昆嵛山岩体与古元古代荆山群变质岩接触带附近的昆嵛山岩体中,受唐家沟断裂及其次级北东向断裂控制。矿体呈串珠状等间距分布,沿走向分支复合、膨胀夹缩现象明显。围岩昆嵛山二长花岗岩锆石LA-ICP-MS U-Pb测年结果为157.57±0.82Ma,含金石英脉中热液独居石LA-ICP-MS U-Pb测年结果为122.1±2.8Ma,代表了金矿的成矿时代。结合近年来已有成果,认为昆嵛山岩体是陆陆挤压碰撞环境下,地壳部分熔融形成的,与金成矿无直接关系,为成矿前构造-岩浆活动的产物;早白垩世,古太平洋板块向欧亚板块俯冲,构造体制由挤压向伸展转换,形成一套壳幔混合型花岗岩,成矿作用发生于岩浆作用晚期,时代集中于117-122Ma,为牟平-乳山成矿带成矿期构造-岩浆活动的代表;110-120Ma,胶东地区岩石圈强烈减薄,在伸展的构造环境下发育的三佛山岩体,与成矿无直接关系。
The Tangjiagou gold deposit is a quartz vein type deposit in the Muping-Rushan metallogenic belt, Jiaodong Peninsula. The orebody occurs in the Kunyushan rock mass near the contact zone between the Kunyushan monzogranite and the Jingshan Group metamorphic rock of the Paleoproterozoic, and is controlled by the Tangjiagou fault and its NE secondary faults. The orebodies are distributed in equidistant bead-like pattern and characterized by branching and recombination as well as expansion and pinch-out. As measuredby zircon LA-ICP-MS U-Pb method, the Kunyushan monzogranite was formed at 157.57±0.82 Ma. Monazite in quartz vein bearing Au of Tangjiagou gold deposit was formed at 122.1±2.8 Ma, which indicates the metallogenic epoch. Combined with previous data, it is proposed that the Kunyushan monzograniteare unrelated to gold deposits and belong to tectonomagmatic activity before mineralization, which formed in the partial melting of crust at the Continental compressional collision environment. The Paleo-Pacific Plate subducted Eurasian Plate in early Cretaceous Epoch, the structural system transforming from compression to extension and the crust and mantle interaction formed mixed magma. The activities were associated with gold deposits of the Muping-Rushan metallogenic belt and belong to tectonomagmatic activity in mineralization, of which the metallogenic Epoch occurred between 117-122 Ma. The lithospheric thinning occurred strongly in Jiaodong areas between 110-120 Ma, the crust and mantle mixed magma formed the Sanfoshan rocks, which are unrelated to gold deposits.
作者
唐文龙
付超
邹键
何江涛
席宏
田杰鹏
党智财
TANG Wenlong;FU Chao;ZOU Jian;HE Jiangtao;XI Hong;TIAN Jiepeng;DANG Zhicai(Tianjin center,China Geology Survey,Tianjin,300170;North China Center for Geoscience Innovation,Tianjin,300170;No.3 Exploration Institute of Geology and Mineral Resources,Yantai,Shandong,264004;China University of Geosciences,Beijing,100083;China Academy of Geological Sciences,Beijing,100037)
出处
《地质学报》
EI
CAS
CSCD
北大核心
2021年第3期809-821,共13页
Acta Geologica Sinica
基金
国家重点研发计划“深地资源勘查开采”重点专项(编号2016YFC0600107、2018YFC0603805)
中国地质调查局项目(编号DD20160044、DD20190155)联合资助成果。
