湘东北金鸡金矿床岩体成岩机制 |
|
关键词:granite granodiorite petrogeochemistry geochronology Jinji Au deposit Jiangnan orogenic belt |
基金项目:国家重点研发计划“深地资源勘查开采”重点专项课题(编号: 2017YFC0601501);中南大学创新驱动计划(编号: 1053320180985) |
|
摘要点击次数: 4141 |
全文下载次数: 2360 |
摘要: |
Petrogenesis of the Granitoids in the Jinji Au Deposit, Northeastern Hunan Province |
The Middle–Early Paleozoic granitoids in Hunan section of the Jiangnan orogenic belt are of great significance for the study of the Early Paleozoic tectonic evolution and gold mineralization. Two types of granitoids, i.e., granite and granodiorite, were recently found in the Jinji gold deposit, which is located in the central section of the orogenic belt. Two types of rock samples were dated by zircon La-ICPMS U-Pb technique, and the results show that the granite and granodiorite yielded U-Pb zircon ages of (425.2±1.5) Ma and (430.6±1.5) Ma, respectively. The geochemical data showes that the granite belongs to I-type granite, which was derived from partial melting of metapelitic rocks in the crust; the granodiorite belongs to adakite, which was derived from partial melting of metasandy rocks in the crust. The Sr-Nd isotopic analysis shows that the granodiorite has higher (87Sr/86Sr)i values of 0.722 369 and 0.722 488, lower (143Nd/144Nd)i values of 0.511 941 and 0.511 990 and lower εNd(t) values of 8.2 and 7.2, and the two-stage Nd model ages of the granodiorite are 1.75 Ga and 1.84 Ga, which are consistent with the ages of metamorphic basement in the Jiangnan orogenic belt (1.65~2.14 Ga). The petrogeochemical, geochronologic and Sr-Nd isotopic characteristics of granites and granodiorites in the Jinji gold deposit indicate that they were produced by Early Paleozoic intracontinental orogenic events in South China, and the results help to investigate the geodynamic mechanism for Au mineralization in northeastern Hunan Province. |
WEI Han-tao,SHAO Yong-jun,WANG Cheng,LIU Qing-quan,LIU Zhong-fa,XIAO Ke-yan.2020.Petrogenesis of the Granitoids in the Jinji Au Deposit, Northeastern Hunan Province[J].Acta Geoscientica Sinica,41(2):253-266. |
查看全文 查看/发表评论 下载PDF阅读器 |
|
|
|
|
|