Petrochemistry and Tectonic Setting of the Middle Triassic Arc-Like Volcanic Rocks in the Sayabouli Area, NW Laos

摘要：

　　The volcanic rocks from the Sayabouli area in northwestern Laos have been poorly studied.These volcanic rocks are traditionally mapped as the Permian-Early Triassic sequences on the geological map.One basaltic-andesite from the Sayabouli area yields a zircon U-Pb age of 237.7±1.7 Ma, suggesting a Middle Triassic origin.All basalt and basaltic-andesite samples from the Sayabouli area show depletions in HFSEs (e.g., Nb, Ta, Ti) and have high LILE/HFSE ratios, and exhibit the geochemical affinity to the continental arc volcanic rocks and are geochemically similar to the continental arc volcanic rocks from the Phetchabun belt in northeastern Thailand, suggesting a Late Permian-Middle Triassic continental margin in the Sayabouli area of northwestern Laos and Phetchabun area of northeastern Thailand.Our data indicate that the Phetchabun arc volcanic belt through the western Loei sub-belt can be linked to the Sayabouli area in northwestern Laos.

关键词： volcanic rock geochemical characteristics zircon U-Pb age Middle Triassic Sayabouli northwestern Laos

作者: Xin Qian Qinglai Feng Yuejun Wang Wenqiang Yang Chongpan Chonglakmani Denchok Monjai

作者单位: State Key Laboratory of Geological Processes and Mineral Resources, China University of Geosciences, School of Earth Science and Geological Engineering, Sun Yat-sen University, Guangzhou 510275, China; State Key Laboratory of Geological Processes and Mineral Resources, China University of Geosciences, School of Geotechnology, Suranaree University of Technology, Nakhon Ratchasima 30000, Thailand

会议类型: 国际会议

会议名称: 第二届亚洲特提斯造山与成矿国际学术研讨会

会议地点: 武汉

会议语种:英文

页码: 365-377

在线出版日期: 2015-10-16（万方平台首次上网日期，不代表论文的发表时间）