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Depositional age and geological implications of the Ruyang Group in the southwestern margin of the North China Craton: Evidence from detrital zircon U-Pb ages

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Abstract

The Ruyang Group distributes in the southwestern margin of the North China Craton, mainly locating in the border of Henan-Shaanxi-Shanxi Province. The Group, covering on the Xiong'er Group with angular unconformity and being overlain consistently by the Luoyu Group, is mainly composed of unmetamorphosed clastic and carbonate strata. In this paper, the authors reports LA-ICP-MS U-Pb ages from four quartz sandstones of the Baicaoping Formation of the Ruyang Group. The youngest 207Pb/206Pb ages are1 817±22 Ma, 1838±23 Ma, 1924±17 Ma and 1829±28 Ma, respectively. Those ages combined with the high-precise dates 1611±8 Ma in the Luoyu Group overlying on the Ruyang Group indicate that the Ruyang Group should be early Mesoproterozoic. The207Pb/206Pb ages of the detrital zircon range from 3000 Ma to 1800 Ma, with 67% between 2600 Ma to 2400 Ma and the main peak of ages(2550~2500 Ma), meaning that sedimentary materials mainly sourced from Paleoproterozoic geologic bodies.

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... The authors declared that there is no conflict of interest. (Zhou et al., 2008;Hu et al., 2009Hu et al., , 2012aHu et al., , 2012bHu et al., , 2014aHu et al., , 2014bGao et al., 2011;Ying et al., 2011;Zhu et al., 2011;Wan et al., 2011;Yang et al., 2012;Li et al., 2013;Lan et al., 2014;Liu et al., 2014Liu et al., , 2017aLiu et al., , 2017cMa et al., 2014;Zhong et al., 2015;Zhang et al., 2016;Dong et al., 2017;Li et al., 2018;Meng et al., 2018); (b) the Xuhuai Basin (Zhou et al., 2008;Gao et al., 2011;Hu et al., 2012a;Yang et al., 2012;He et al., 2016); (c) the Zhaertai-Bayan Obo-Huade Basin (Hu et al., 2009(Hu et al., , 2014aMa et al., 2014;Liu et al., 2014Liu et al., , 2017cZhong et al., 2015;Li et al., 2018); (d) the Yanliao Basin (Gao et al., 2011;Wan et al., 2011;Ying et al., 2011;Wang et al., 2017); (e) the Xiong'er Basin (Zhu et al., 2011;Hu et al., 2012bHu et al., , 2014bLi et al., 2013;Lan et al., 2014;Zhang et al., 2016;Dong et al., 2017;Liu et al., 2017a;Meng et al., 2018). and editorial guidance are greatly appreciated. ...
... The authors declared that there is no conflict of interest. (Zhou et al., 2008;Hu et al., 2009Hu et al., , 2012aHu et al., , 2012bHu et al., , 2014aHu et al., , 2014bGao et al., 2011;Ying et al., 2011;Zhu et al., 2011;Wan et al., 2011;Yang et al., 2012;Li et al., 2013;Lan et al., 2014;Liu et al., 2014Liu et al., , 2017aLiu et al., , 2017cMa et al., 2014;Zhong et al., 2015;Zhang et al., 2016;Dong et al., 2017;Li et al., 2018;Meng et al., 2018); (b) the Xuhuai Basin (Zhou et al., 2008;Gao et al., 2011;Hu et al., 2012a;Yang et al., 2012;He et al., 2016); (c) the Zhaertai-Bayan Obo-Huade Basin (Hu et al., 2009(Hu et al., , 2014aMa et al., 2014;Liu et al., 2014Liu et al., , 2017cZhong et al., 2015;Li et al., 2018); (d) the Yanliao Basin (Gao et al., 2011;Wan et al., 2011;Ying et al., 2011;Wang et al., 2017); (e) the Xiong'er Basin (Zhu et al., 2011;Hu et al., 2012bHu et al., , 2014bLi et al., 2013;Lan et al., 2014;Zhang et al., 2016;Dong et al., 2017;Liu et al., 2017a;Meng et al., 2018). and editorial guidance are greatly appreciated. ...
... The Baicaoping and Beidajian formations of the Ruyang Group are dominated by fine-grained rocks and lack effective detrital zircon ages. The youngest detrital zircon Pb-Pb concordant age of 1817 ± 22 Ma has been reported from the quartz sandstone of the Baicaoping Formation (Li et al., 2013b). A zircon U-Pb age of 1648.4 ± 6.5 Ma obtained from the tuffaceous layer in the lower part of Cuizhuang Formation of the Luoyu Group in the Yongji section, Shanxi Province , limited the minimum age of Ruyang Group to ca. 1.65 Ga. ...
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According to the isotopic age data of inherited zircons in igneous and metamorphic rocks which occur at the surface and are derived from deep crust of the North China, Yangtze blocks and Qinling - Dabie orogenic belt, the paper is mainly reports some new information of Archean rocks (basement) and briefly discusses its geological significance. The deep crust of 6 areas on the northeastern, southeastern, northern and northwestern margin of the North China Block all show new information of Neoarchean, Mesoarchean and Paleoarchean magmatic events, and the deep crust of the southern margin demonstrates the existence of Paleoarchean magmatic event. In the histogram of isotopic data of early Precambrian of the North China Block, the highest peak is between 2.45 Ga and 2.6 Ga, where the 2.5-2.55 Ga culmination is most striking, suggesting that the magmatic event is strongest at the time span and the there was a possible important continent collision event then. While the other minor peaks at 2.7 Ga, 2.8-2.85 Ga, 2.95-3.0 Ga, 3.1-3.15 Ga, 3.3-3.4 Ga, 3.45-3.5 Ga, 3.6 Ga and 3.8 Ga may reflect the different stages of the evolving magmatic activity. Information of Archean materials similar to that of the North China Block can be found on the surface and in the deep crust of the northern margin of the Yangtze Block. New data of Neoarchean and/or Paleoarchean from inherited magmatic zircons can be obtained from rocks derived from the deep crust in the middle - lower reaches of the Yangtze River, southeastern margin of the Yangtze block (corresponding to the former Jiangnan paleocontinent) and region of the southwestern margin of the Yangtze block. In the Qinling - Dabie orogenic belt, the rocks which are mainly out of the deep crust at many localities from east to west have given Neo-Mesoarchean evidence by the inherited magmatic zircons.
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