Based on the results of four regional geological surveys of 1:50000 including Shulan County map in Jilin, taking Shulan area as the study area,the authors re-delineated the rock type assemblages, e.g. metamorphic rhyolite, metamorphic tuffaceous breccia lava, sericite-quartz schist and tremolite altered rock, etc., and the structural contacts between them. With the help of in-situ LA-ICP-MS U-Pb dating for zircons, it is concluded that the zircon crystallization ages of the metamorphic rhyolite, the metamorphic andesitic tuff breccia lava and the tremolite altered rock are 339.1±1.3 Ma(n=27,MSWD=0.78),351.8±1.7 Ma(n=21,MSWD=0.82),and 362.0±1.8 Ma(n=43, MSWD=2.2) respectively. The metamorphic complex is actually a set of tectonic melange which comprises the rocks in different types, sources, times, or tectonic settings, and was formed by tectonism.
Key words
central Jilin /
Jifanggou metamorphic complex /
zircon LA-ICP-MS U-Pb age /
tectonic melange
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Funding
Supported by projects of China Geological Survey (Nos.DD20160049, 12120114029101)
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