Zircon U-Pb and Molybdenite Re-Os Dating and Geological Implications of the Shimadong Porphyry Molybdenum Deposit in Eastern Yanbian, NE China
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Canadian Journal of Earth Sciences Zircon U-Pb and Molybdenite Re-Os Dating and Geological Implications of the Shimadong Porphyry Molybdenum Deposit in Eastern Yanbian, NE China Journal: Canadian Journal of Earth Sciences Manuscript ID cjes-2019-0014.R2 Manuscript Type: Article Date Submitted by the 29-May-2019 Author: Complete List of Authors: Nie, Xi-Tao; Jilin University, College of Earth Sciences Sun, Jing-Gui; Jilin University, College of Earth Sciences; Sun, Feng-Yue; Jilin University, College of Earth Sciences Li, Bi-Le; JilinDraft University, College of Earth Sciences Zhang, Ya-Jing; Jilin University, College of Earth Sciences Liu, Wan-Zhen; Jilin Institute of Geological Survey zircon U-Pb dating, molybdenite Re-Os dating, Geochemistry, Hf isotope, Keyword: Shimadong porphyry Mo deposit Is the invited manuscript for consideration in a Special Not applicable (regular submission) Issue? : https://mc06.manuscriptcentral.com/cjes-pubs Page 1 of 59 Canadian Journal of Earth Sciences 1 Zircon U-Pb and Molybdenite Re-Os Dating and Geological 2 Implications of the Shimadong Porphyry Molybdenum 3 Deposit in Eastern Yanbian, NE China 4 5 Xitao Nie1,2, Jinggui Sun1, Fengyue Sun1,*, Bile Li1, Yajing Zhang1, and Wanzhen 6 Liu2 7 8 1 College of Earth Sciences, Jilin University, Changchun 130061, China; 9 10 2 Jilin Institute of Geological Survey, Changchun 130061, China 11 12 * Corresponding author: Feng-Yue Sun, College of Earth Sciences, Jilin University, 13 No. 2166, Jianshe Street, Changchun 130061, China 14 15 E-mail: [email protected] 16 17 Tel.:+86 431 88502055 Draft 18 19 ABSTRACT 20 The Shimadong porphyry Mo deposit is located in eastern Yanbian, in the eastern part 21 of the north margin of the North China craton (NCC), NE China. Here, we present the 22 whole-rock major and trace elements, zircon U-Pb and Hf isotope data, and 23 molybdenite Re-Os data for the Shimadong deposit. The porphyry was emplaced at 24 163.7 ± 0.9 Ma and the mineralization at 163.1 ± 0.9 Ma, suggesting that the 25 mineralization was associated with the emplacement of the Shimadong porphyritic 26 monzogranite. The porphyritic monzogranite had high SiO2 (70.09–70.55 wt%) and 27 K2O + Na2O (7.98–8.27 wt%) contents and low MgO (0.51–0.53 wt%), TFeO 28 (2.4–2.47 wt%), CaO (2.19–2.26 wt%), and K2O/Na2O (0.8–0.82) contents. The 29 porphyry was rich in large ion lithophile elements Rb, Ba, K, and Sr, depleted in https://mc06.manuscriptcentral.com/cjes-pubs Canadian Journal of Earth Sciences Page 2 of 59 30 high-field strength elements Y, Nb, Ta, P, and Ti, without significant Eu anomaly 31 (δEu = 0.86-1.00), and depleted in heavy REE (HREEs) with LREE/HREE = 32 18.25–20.72 and (La/Yb)N =27.10–34.67. These features are similar to those of 33 adakitic rocks derived from a thickened lower crust. Zircon εHf(t) values for the 34 porphyritic monzogranite ranged from −19.2 to 6.3, and the two-stage Hf model ages 35 (TDM2) was 811–2421 Ma. These data indicate that the primary magma of the 36 Shimadong porphyritic monzogranite was mainly derived from partial melting of the 37 thickened lower crust consisting of juvenile crust and pre-existing crust. Combined 38 with the results of previous studies, our data suggest that the Shimadong porphyry Mo 39 deposit was emplaced along an activeDraft continental margin related to the westward 40 subduction of the paleo-Pacific Plate. 41 Keywords: Zircon U-Pb dating, Molybdenite Re-Os dating, Geochemistry, Hf isotope, 42 Shimadong porphyry Mo deposit, NE China. 43 1 Introduction 44 One of the largest molybdenum metallogenic belts in NE China, the east Xingmeng 45 orogenic belt (EXOB) is a segment of the east Central Asian orogenic belt (CAOB) 46 (Mao et al., 2011; Zeng et al., 2012a, 2013). The Paleozoic tectonic evolution of the 47 EXOB was dominated by the closure of the Paleo-Asian Ocean and consisted of 48 collisions of microcontinental blocks between the Siberian craton and the North China 49 craton (NCC). These blocks include the Khanka, Jiamusi, Songnen, Yanbian, Erguna, 50 Xing’an and Zhangguangcai massifs, all of which are separated from each other by https://mc06.manuscriptcentral.com/cjes-pubs Page 3 of 59 Canadian Journal of Earth Sciences 51 major faults (Wu et al.,2000, 2001, 2004, 2007a, 2007b, 2011; Sun, 2001; Sun et al., 52 2005a,b, 2013; Zhang et al., 2010; Meng et al., 2010, 2011; Zhou et al., 2010a,b,c; 53 Cao et al., 2012, 2013; Tang et al., 2013; Li et al., 2014; Wang et al., 2015a, 2015b; 54 Yang et al., 2017) (Fig. 1). The Mesozoic and Cenozoic tectonic evolutions were 55 caused by subduction of the paleo-Pacific plate beneath the East Asian continent, 56 superimposed on the EXOB and NCC (Li et al., 1999, 2009; Wu et al., 2007b, 2011; 57 Yu et al., 2012; Xu et al., 2013; Guo et al., 2015). 58 In the EXOB region, super-giant Mo deposits, such as the Chalukou, Luming and 59 Daheishan deposits, giant and medium scale Mo deposits, such as the Fuanpu, Jidetun, 60 Dongfeng, and Shimadong deposits,Draft and small-scale Mo deposits, such as the 61 Liushengdian and Sancha (Fig. 1) occur. 62 These Mo deposits are mainly porphyry type, followed by skarn or hydrothermal 63 vein types (Chen et al., 2012, 2017; Zhang, 2013b; Zhao, 2016; Zeng et al., 2018a). In 64 recent years, some studies have been conducted on molybdenum mines in the Jilin 65 Province, primarily focusing on three aspects of the system: (1) the mineralization 66 periods mainly concentrated between 163-195 Ma (Ge et al., 2007; Wang et al., 2009; 67 Wang, 2011; Di, 2011; Ju, 2012; Zhang, 2013a; Song, 2016; Guo et al., 2018; Zeng et 68 al., 2018; Zhou et al., 2018) and 110-128Ma (Sun et al., 2001; Zeng et al., 2010a, 69 2012b; Huang, 2014; Zhao, 2016), (2) the ore-forming materials derived from a 70 crustal source (Sun et al., 2001; Zhang, 2013a; Ju et al., 2012) or a mixed crustal and 71 mantle source (Sun et al., 2001; Li et al., 2009; Wang et al., 2009; Zhou et al., 2013; 72 Zhang, 2013a), and (3) magma originating in the ancient crust (Farmer and DePaolo, https://mc06.manuscriptcentral.com/cjes-pubs Canadian Journal of Earth Sciences Page 4 of 59 73 1984; Carten et al., 1993; Chen et al., 2000), partial melting of the lithospheric mantle 74 by percolated of subduction fluids (Westra and Keith, 1981; Pettke et al., 2010), and 75 partial melting of a thickened lower crust (Petford and Atherton, 1996; Kay and Kay, 76 2002; Hou et al., 2009; Chen et al., 2009; Guo et al., 2018). The Shimadong Mo 77 deposit is newly discovered medium scale deposit with 100,000 tons of ores at an 78 average grade of 0.08% Mo (Pei, 2012). However, the nature of the magma and the 79 mineralization constraints remain undetermined and the metallogenic tectonic 80 background is unknown. In order to solve the above problems, this paper presents the 81 zircon U-Pb ages, in-situ Hf isotopic, and whole-rock elemental compositions of the 82 porphyritic monzogranites as wellDraft as the molybdenite Re-Os ages in the Shimadong 83 Mo deposit. 84 2 Regional geologic setting 85 Composed of a basement and cover layer, the eastern Yanbian region is located in 86 the EXOB and NCC. The basement was formed by the late Archean Jiapigou Group 87 (2.5 Ga; Wu, 2017), granitic gneiss, and the Permian Qinglongcun Group (Jia, 1994; 88 Zhang, 2003; Qiu et al., 2004). The former two units are distributed on the NCC, and 89 the main lithologies are amphibole and amphibole plagioclase gneiss, metamorphic 90 hornblende diorite, metamorphic monzogranite, and other similar rock types. The 91 latter unit is distributed in the EXOB and includes marble of the Changren Formation 92 and griotte and gneiss from the Xindongcun Formation (274-250 Ma; Zhang et al., 93 2007; Zhou et al., 2013b; Zhou, 2017). The cover layer consists of Mesozoic https://mc06.manuscriptcentral.com/cjes-pubs Page 5 of 59 Canadian Journal of Earth Sciences 94 sedimentary rocks (Lei, 2015). The Mesozoic rift basin is mainly composed of the 95 Cretaceous Changcai Formation, Quanshuicun Formation, Dalazi Formation, and 96 Longjing Formation (Lei, 2015; Chen, 2017). The rocks in the rift basin constitute a 97 set of river-lake face clastic rocks and volcanic-volcaniclastic rocks. The distribution 98 of the rocks is fault controlled. The Cenozoic basalt of the Chuandishan Formation is 99 the youngest stratum exposed in the region and is found on the west side of the area. 100 Intrusive rocks in the region are widely distributed, and the shape and spatial 101 distribution of the rocks are observably controlled by the regional fault. The 102 distribution of the Archean tonalite and the Paleozoic complex rocks are limited and 103 scattered. The rocks have developedDraft schistosity, and the schistosity direction is 104 consistent with the regional tectonic line. A small number of mafic-ultramafic dikes 105 formed from 255–217 Ma are mainly related to copper nickel sulfide deposits (Wu et 106 al., 2004; Xie et al., 2007; Zhou, 2017; Wang, 2018). The Mesozoic granites that are 107 exposed over a large range, are mainly was divided into two periods: 166–195 Ma 108 (Sun, 2010; Zhang, 2013b; Zhang, 2014; Zhou et al., 2013; Zeng et al., 2018), and 109 111–128 Ma (Sun et al., 2012; Zhao, 2016).