PRECISE AGE CONSTRAINTS FOR THE WOXI Au-Sb-W DEPOSIT, SOUTH CHINA
PRECISE AGE CONSTRAINTS FOR THE WOXI Au-Sb-W DEPOSIT, SOUTH CHINA
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DOI：
10.5382/econgeo.4971
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发表时间：
2022-08
期刊：
影响因子：
5.8
通讯作者：
Wei Li;Guiqing Xie;J. Mao;N. Cook;Han-Tao Wei;Yunhao Ji;B. Fu
中科院分区：
文献类型：
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作者：
Wei Li;Guiqing Xie;J. Mao;N. Cook;Han-Tao Wei;Yunhao Ji;B. Fu
准确确定变质沉积岩中金锑钨矿床的形成时间一直是广泛研究的目标，但也引起了争议。采用高精度激光烧蚀-电感耦合等离子体质谱（LA-ICP-MS）对沃溪金锑钨存款矿床中的热液磷灰石和黑钨矿进行了U-Pb定年。矿脉主要由石英、自然金、含金黄铁矿、毒砂、辉锑矿、白钨矿、黑钨矿和磷灰石组成。黑钨矿颗粒的U-Pb年龄为144.8 ± 1.5Ma（2s）和140.3 ± 1.4Ma，与磷灰石年龄148.7 ± 2.4 ~ 144.1 ± 2.7Ma重叠。总的来说，新的数据证实了沃溪存款的年龄完全是晚侏罗世-早白垩世，尽管以前使用其他同位素系统的年龄是志留纪。本文通过对江南带西段金锑钨矿床地质特征、构造背景和成矿年代学的综合研究，认为该区金锑钨成矿作用存在两期。这些事件发生在晚三叠世和晚侏罗世-早白垩世，分别与三叠纪陆内造山作用后的伸展背景和与伊那木板块回滚相关的晚侏罗世-早白垩世伸展有关。
Accurately resolving the timing of formation of Au-Sb-W deposits hosted in metasedimentary rocks has been the aim of extensive research but has also led to controversy. In this study, we present high-precision laser ablation-inductively coupled plasma-mass spectrometry (LA-ICP-MS) U-Pb dating of hydrothermal apatite and wolframite from the Woxi Au-Sb-W deposit, South China. Veins are dominated by quartz, native gold, auriferous pyrite, arsenopyrite, stibnite, scheelite, wolframite, and apatite. Wolframite grains yield U-Pb ages of 144.8 ± 1.5 Ma (2s) and 140.3 ± 1.4 Ma, which overlap with apatite ages of 148.7 ± 2.4 to 144.1 ± 2.7 Ma. Collectively, the new data confirm the Woxi deposit is solely Late Jurassic-Early Cretaceous in age, despite previous dates using other isotopic systems that were as old as Silurian. Our compilation of geologic characteristics, tectonic setting, and geochronology of Au-Sb-W deposits from the western part of the Jiangnan belt shows there were two episodes of Au-Sb-W metallogenesis. These events in the Late Triassic and Late Jurassic-Early Cretaceous related to an extensional setting following Triassic intracontinental orogeny and to Late Jurassic-Early Cretaceous extension associated with Izanagi plate rollback, respectively.