会议专题

U-Pb Geochronology of Detrital and Inherited Zircons in the Yidun Arc Belt, Eastern Tibet Plateau and Its Tectonic Implications

  This paper reports geochronological data of detrital zircons from the country rock and sedimentary xenoliths of the Cilincuo pluton (79±0.7 Ma) in the southern Yidun arc belt and the inherited zircons from the Late Triassic granites in the eastern Yidun arc belt, eastern Tibet Plateau.Detrital zircons ages from the sedimentary xenoliths have four prominent peaks at 2.5-2.4 Ga, 1.9-1.8 Ga, 480-400 Ma, and 350-300 Ma, whereas those from the country rock exhibit another four prominent peaks at 1.9-1.8 Ga, 850-700 Ma, 480-400 Ma, and 300-250 Ma.Based on comparison with age data from previous studies, we suggest that the sedimentary xenoliths are from the Lanashan Formation and the major provenance of them is Qiangtang Block, Zhongza massif and South China Block, whereas the country rock belongs to the Lamaya Formation and the major provenance of them is similar to those of the neighbouring Songpan-Garzê terrane.In addition, the inherited zircons from the Late Triassic granites in the eastern Yidun arc belts have a prominent Neoproterozoic age population (900-700 Ma), which suggests that there is an old basement with west Yangtze Craton affinity beneath the Triassic sediments.Combining with previous studies, we propose that the provenances of the formations vary from the Lanashan Formation to the Lamaya Formation which may indicate a record of the final closure of the Garzê-Litang Ocean.

Yidun arc belt Garze-Litang Ocean basement detrital zircon inherited zircon

Tao Wu Long Xiao Changqian Ma

School of Earth Sciences, Zhejiang University, Hangzhou 310027, China;School of Earth Sciences, Chin School of Earth Sciences, China University of Geosciences, Wuhan 430074, China School of Earth Sciences, China University of Geosciences, Wuhan 430074, China;State Key Laboratory

国际会议

第二届亚洲特提斯造山与成矿国际学术研讨会

武汉

英文

461-473

2015-10-16(万方平台首次上网日期,不代表论文的发表时间)