Re-Os and U-Pb geochronology for the Xiaorequanzi VMS deposit in the Eastern Tianshan, NW China: Constraints on the timing of mineralization and stratigraphy
Autor: | Jingbin Wang, Qigui Mao, Xiaoqiang Lü, Mingjie Yu, Xiao-Hua Deng, Songjian Ao, Yuechen Li |
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Rok vydání: | 2020 |
Předmět: |
Isochron
Mineralization (geology) Paleozoic 020209 energy Geochemistry Geology 02 engineering and technology 010502 geochemistry & geophysics Dacite 01 natural sciences Geochemistry and Petrology Carboniferous Geochronology 0202 electrical engineering electronic engineering information engineering Island arc Economic Geology 0105 earth and related environmental sciences Zircon |
Zdroj: | Ore Geology Reviews. 122:103473 |
ISSN: | 0169-1368 |
Popis: | The Xiaoriquanzi volcanogenic massive sulfide (VMS) Cu-Zn deposit occurs at the western part of the Paleozoic Dananhu-Haerlik arc in the eastern Tianshan, Xinjiang, China. Due to a lack of precise mineralization ages, the metallogenesis of the deposit has long been debated. In this study, systematic geochronological methods are used to constrain the mineralization age of the deposit. The deposit is hosted in the Xiaorequanzi Formation volcanic-sedimentary rocks. The orebodies occur as clusters of lenticular bodies with or without banding, and they are controlled by the NW-trending acticline. The ore types contain massive, banded, laminated and chlorite-enriched ores as well as vein-type, veinlet-dissemination and dissemination ores. In this study, Re-Os dating of the chalcopyrite from the Xiaorequanzi deposit yields an isochron age of 354 ± 11 Ma and initial 187Os/188Os ratios of 0.39 ± 0.14, which is consistent with the zircon U-Pb ages of ore-hosted tuff sandstone and dacite at 357.3 ± 2.4 Ma and 359.5 ± 3.4 Ma, respectively. Zircon U-Pb dating reveals that the mineralized granite porphyry formed at 354.7 ± 3.2 Ma, and this age is similar to the exhalative syn-sedimentary mineralization age (354 ± 11 Ma). Thus, precise geochronologic studies reveal that the seafloor volcanic hydrothermal system formed exhalative syn-sedimentary mineralization in the local extensional basin of the Dananhu-Haerlik arc during the Early Carboniferous (354–357 Ma). From Early Silurian to Carboniferous, two epochs VMS and porphyry deposits alternately formed in Dananhu-Haerlik long-lived arc. This reveals complicated arcs-basins tectonic transformation at the island arc setting. |
Databáze: | OpenAIRE |
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