Li H.,China University of Geosciences |
Zhang D.,China University of Geosciences |
Zhou Z.,China University of Geosciences |
Liu C.,China University of Geosciences |
And 3 more authors.
Jilin Daxue Xuebao (Diqiu Kexue Ban)/Journal of Jilin University (Earth Science Edition) | Year: 2016
Hexigten Qi is located to the north of Xar Moron River, tectonically on the south margin of Xilinhot massif. The authors conduct the analysis on the detrital zircon LA-ICP-MS U-Pb dating for the metasiltstones of Linxi Formation from a ca.5 km outcrop in the northeastern Hexigten Qi. The samples yield 4 groups of ages principally at: 258-298 Ma (peak at 285 Ma), 377-474 Ma (peak at 430 Ma), 1261-1727 Ma, and 1853-2513 Ma. Besides, two zircons yield the age of 321 Ma and 937 Ma respectively. Zirons aged 258-298 Ma show oscillatory zones in CL images, reflecting the magmatic events in Late Paleozoic along Xing'an-Mongolia orogenic belt. Zircons with 377-474 Ma ages are featured by both magmatic and metamorphic origins, suggesting that the provenances of Linxi Formation in Hexigten Qi probably were from Ordovician-Devonian magmatic and Paleozoic metamorphic rocks. Zircons yielded ages of 1261-1727 Ma are dominated by magmatic zircons, with some metamorphic zircons; indicating that the Mesoproterozoic magmatic and metamorphic rocks are also the provenances of Linxi Formation. Most of the Zircons aged 1853-2513 Ma are of magmatic origin, showing the old age information from North China Craton (NCC). The youngest age from this metasiltstone is 258 Ma, which constrains the deposition age of Linxi Formation to Late Permian. The broad scope of ages reflects the tectono-magmatic events both in NCC and Xing'an-Mongolia orogenic belt, and indicates that Linxi Formation has two provenances, and also implies that NCC and Siberia plate had amalgamated before Linxi Formation deposited. © 2016, Jilin University Press. All right reserved.