Age and Provenance of Upper Shilidun Formation, Lintan, West Qinling Orogen: Constraints from LA-ICP-MS U-Pb Dating of Detrital Zircons

被引：4
|
作者：
Gao X. [1 ]
Pei X. [1 ,2 ]
Li Z. [1 ,2 ]
Li R. [1 ,2 ]
Wei L. [3 ]
Wang M. [1 ,2 ]
Liu C. [1 ,2 ]
Gao F. [1 ]
Liang G. [1 ]
Shao J. [1 ]
Mu K. [1 ]
机构：
[1] School of Earth Science and Resources, Chang'an University, Xi'an
[2] Key Laboratory for the Study of Focused Magmatism and Giant Ore Deposits, Ministry of Land and Resources, Xi'an
[3] No.5 Gold Geological Party of the Chinese Armed Police Force, Xi'an
来源：
Diqiu Kexue - Zhongguo Dizhi Daxue Xuebao/Earth Science - Journal of China University of Geosciences | 2019年 / 44卷 / 04期
关键词：
Lintan area; Petrology; Shilidun Formation; West Qinling orogen; Zircon LA-ICP-MS U-Pb dating;
D O I：
10.3799/dqkx.2018.122
中图分类号：
学科分类号：
摘要：
According to previous studies, there are short of standard fossils to define the formed age of Shilidun Formation, which leads to many disputes about the depositionl time, and correlation studies on the provenance of Shilidun Formation are rare. LA-ICP-MS detrital zircon U-Pb dating was conducted for clastic rocks in the upper Shilidun Formation, Lintan area, to investigate the age and provenance in this study. The results show that the weighted mean age of the youngest zircon age group in the two samples is 265.7±6.5 Ma, representing the maximum depositional age of the upper Shilidun Formation. Taking the paleontological data into consideration, it is suggested that the upper Shilidun Formation was deposited in the Middle-Late Permian. The detrital zircon ages are divided into 4 groups:① Phanerozoic age group (265-467 Ma); ② Neoproterozoic age group (564-996 Ma), with a small peak at 955 Ma; ③ Mesoproterozoic age group (1 099-1 539 Ma); ④ Paleoproterozoic-Archaean age group (1 622-3 153 Ma), which can be subdivided into two groups:the Middle and Late Paleoproterozoic age group (1 622-2 194 Ma), with an obvious peak at 1 902 Ma; the Early Paleoproterozoic age group (2 343-3 153 Ma), with an obvious peak at 2 516 Ma.According to the characteristics of the detrital zircon spectra, it is thought that the upper Shilidun Formation has multi-sources, including the southern margin of the North China block, the eastern section of the Qilian orogenic belt, the northern margin of the West Qinling tectonic zone, and ancient basement of the southern margin of the North China block is main source region. Based on the sedimentary facies, lithofacies paleogeography and regional tectonic evolution, it is proposed that the upper Shilidun Formation should be formed in the northern slope of the back arc basin formed by the subduction of the Yangtze plate and the convergence of the Mianlue Ocean. © 2019, Editorial Department of Earth Science. All right reserved.
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页码：1389 / 1405
页数：16
相关论文
共 89 条
  • [11] Dong Z.C., Gu P.Y., Chen R.M., Et al., Geochronology, Geochemistry, and Hf Isotope of Yanchangbeishan Adamellite of Lenghu Area in Qinghai, Earth Science, 40, 1, pp. 130-144, (2015)
  • [12] Dong Z.C., Xiao P.X., Gu P.Y., Et al., Geochronology, Geochemistry and Hf Isotope Characteristics of Yanchangbeishan Granodiorite of Lenghu Area in Qinghai, Northwestern Geology, 47, 4, pp. 141-155, (2014)
  • [13] Du Y.S., Sedimentary Geology and Dynamic Sedimentology of the Devonian Strata in the West Qinling Orogenic Belt: Sedimentary Characteristics and Framework of the Devonian Rift Trough and Motianling Terrane in the Southern Belt of the West Qinling Orogenic Belt, Sedimentary Facies and Palaeogeography, 15, 6, pp. 48-61, (1995)
  • [14] Du Y.S., Yin H.F., Wang Z.P., The Late Caledonian-Early Hercynian Basin's Framework and Tectonic Evolution of Qinling Orogenic Belt, Earth Science, 22, 4, pp. 401-405, (1997)
  • [15] Feng Y.M., The Fossil Chaos in the West Qinling Mountains and Its Geological Singnificance, Northwest Geoscience, 3, pp. 52-62, (1981)
  • [16] Feng Y.M., Cao X.D., Zhang E.P., Et al., Tectonic Evolution Framework and Nature of the West Qinling Orogenic Belt, Northwestern Geology, 36, 1, pp. 1-10, (2003)
  • [17] Feng Y.M., Zhu B.Q., Méanges and Tectonic Development of the West Qinling Mountains, Acta Geologica Sinica, 54, 1, (1980)
  • [18] Geng Y.S., Wan Y.S., Shen Q.H., Early Precambrian Basic Volcanism and Crustal Growth in the North China Craton, Acta Geologica Sinica, 76, 2, pp. 199-208, (2002)
  • [19] Geng Y.S., Shen Q.H., Ren L.D., Late Neoarchean to Early Paleoproterozoic Magmatic Events and Tectonothermal Systems in the North China Craton, Acta Petrologica Sinica, 26, 7, pp. 1945-1966, (2010)
  • [20] Regional Geology of Gansu Province, (1989)
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