| Title | Zircon trace elements and magma fertility: insights from porphyry (-skarn) Mo deposits in NE China |
| Authors | Shu, Qihai Chang, Zhaoshan Lai, Yong Hu, Xinlu Wu, Huaying Zhang, Yong Wang, Pin Zhai, Degao Zhang, Cheng |
| Affiliation | China Univ Geosci, State Key Lab Geol Proc & Mineral Resources, Beijing 100083, Peoples R China China Univ Geosci, Sch Earth Sci & Resources, Beijing 100083, Peoples R China James Cook Univ, Coll Sci & Engn, EGRU, Townsville, Qld 4811, Australia James Cook Univ, Acad Grp Geosci, Townsville, Qld 4811, Australia Colorado Sch Mines, Dept Geol & Geol Engn, Golden, CO 80401 USA Peking Univ, Sch Earth & Space Sci, Key Lab Orogen Belt & Crustal Evolut, Beijing 100871, Peoples R China China Univ Geosci, Fac Earth Resources, Wuhan 430074, Hubei, Peoples R China China Met Geol Bur, Inst Mineral Resources Res, Beijing 100025, Peoples R China Chinese Acad Geol Sci, Inst Mineral Resources, MLR Key Lab Metallogeny & Mineral Assessment, Beijing, Peoples R China |
| Keywords | Zircon trace elements Ce and Eu anomalies Magma oxidation states Mo deposits NE China |
| Issue Date | 2019 |
| Publisher | MINERALIUM DEPOSITA |
| Abstract | It has been widely accepted that magmas genetically linked to porphyry (-skarn) Cu (Mo) deposits are commonly oxidized. Recently, using laser ablation-inductively coupled plasma-mass spectrometry (LA-ICP-MS) techniques, zircon Ce4+/Ce3+, Ce-N/Ce-N*, Eu-N/Eu-N*, and Ce/Nd ratios, and magma FMQ values (departure from the fayalite-magnetite-quartz oxygen buffer) based on zircon trace element compositions, have been used as proxies to quantify magma oxidation state. Here we present the zircon trace element compositions of 13 Mesozoic porphyry (-skarn) Mo deposits in NE China of various sizes to examine the relationship between magma Mo fertility and magma oxidation state. Generally, the studied deposits with >0.3Mt Mo have Ce4+/Ce3+>100, Ce-N/Ce-N* >100, Ce/Nd >10, and Eu-N/Eu-N* >0.3, whereas those containing <0.3Mt Mo have Ce4+/Ce3+<100, Ce-N/Ce-N* <100, Ce/Nd <10, and Eu-N/Eu-N* <0.3. The calculated magma FMQ values do not show significant correlation with metal tonnage, probably due to the large uncertainties of the estimated FMQ data. Among these proxies, Ce4+/Ce3+ and Ce-N/Ce-N* ratios show the strongest correlation with Mo tonnage, followed by Ce/Nd and Eu-N/Eu-N*. The above results confirm the previous proposal that zircon Ce and Eu anomalies can represent an intrusion's oxidation state and indicate that the Mo endowment of magmatic-hydrothermal deposits is positively correlated with the magma oxidation state. Compared with Mo-bearing intrusions, the trends for Cu-bearing intrusions are similar but are more complicated, especially for those deposits with >10Mt Cu. The findings in this study can be used to evaluate an intrusion's potential to produce Mo mineralization. |
| URI | http://hdl.handle.net/20.500.11897/548028 |
| ISSN | 0026-4598 |
| DOI | 10.1007/s00126-019-00867-7 |
| Indexed | SCI(E) EI |
| Appears in Collections: | 地球与空间科学学院 造山带与地壳演化教育部重点实验室 |
