摘要
内蒙古中部镶黄旗哈达庙金矿床位于华北板块北缘的中亚造山带中东段,矿体受控于花岗斑岩体与围岩接触带,为斑岩型金矿床。运用激光剥蚀等离子体质谱仪(LA-ICP-MS)测定了含矿花岗斑岩中单颗粒锆石U-Pb年龄,获得15个测试点的加权平均年龄为271.8±3.3Ma(MSWD=2.3,n=15),表明花岗斑岩侵位年龄(或成矿年龄)为早二叠世。结合前人的岩相学、微量元素地球化学和同位素地球化学研究结果,认为哈达庙金矿区花岗斑岩可能形成于古生代末-三叠纪初的华北板块与西伯利亚古板块之间的大陆碰撞背景,俯冲板片部分熔融或者深熔作用形成的岩浆上侵为金矿的形成提供了成矿物质。
The Hadamiao gold deposit in Xianghuangqi, Inner Mongolia, is located at the northern margin of the North China Block. Ore bodies of this deposit are controlled by the contact zones between the Hadamiao granite-porphyry and its country rocks, indicating a porphyry gold deposit type. Zircon grains separated from the ore-bearing granite porphyry, measured by the LA-ICP-MS method, give an age of 271. 8 ± 3. 3Ma (MSWD=2. 3, n=15). This age suggests that the granite porphyry crystallized in early Permian and ore bodies formed more or less simultaneously with this magmatic process. In combination with previously reported petrographical and geochemical results, it can be proposed that the Hadamiao granite porphyry formed in relationship with the collision of the North China and Siberian Blocks during late Paleozoic to early Triassic. The subducted crustal section was partially re-melted to form the magma and magmatic hydrothermal fluid provided ore material for gold mineralization.
出处
《岩石学报》
SCIE
EI
CAS
CSCD
北大核心
2009年第10期2615-2620,共6页
Acta Petrologica Sinica
基金
973项目(编号:2006CB403500)
科技支撑计划项目(编号:2006 BAB01A02 )
中国地质调查局地质调查项目 (编号:1212010813045)资助
