Geochronology and geochemistry of late Paleozoic volcanic rocks on the western margin of the Songnen–Zhangguangcai Range Massif, NE China: Implications for the amalgamation history of the Xing'an and Songnen–Zhangguangcai Range massifs

Lithos 205 (2014) 394–410

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Geochronology and geochemistry of late Paleozoic volcanic rocks on the western margin of the Songnen–Zhangguangcai Range Massif, NE China: Implications for the amalgamation history of the Xing'an and Songnen–Zhangguangcai Range massifs Yu Li a, Wen-Liang Xu a,b,⁎, Feng Wang a, Jie Tang a, Fu-Ping Pei a, Zi-Jin Wang a a b

College of Earth Sciences, Jilin University, Changchun 130061, China State Key Laboratory of Geological Processes and Mineral Resources, China University of Geosciences, Wuhan 430074, China

a r t i c l e

i n f o

Article history: Received 1 April 2014 Accepted 14 July 2014 Available online 21 July 2014 Keywords: Late Paleozoic Volcanic rocks Geochronology Geochemistry Songnen–Zhangguangcai Range Massif Central Asian Orogenic Belt

a b s t r a c t We here elucidate the tectonic evolution of the Xing'an and Songnen–Zhangguangcai Range massifs during the early Carboniferous–early Permian, based on zircon U–Pb dating and whole-rock geochemical analyses of volcanic rocks of the Songnen–Zhangguangcai Range Massif in the Sunwu area, Heilongjiang Province, NE China. Euhedral–subeuhedral zircons from three rhyolites and one dacite from the study area display finescale oscillatory growth zoning, indicating a magmatic origin. Zircon U–Pb dating by LA–ICP–MS indicates that these acidic volcanic rocks formed in the early Carboniferous–early Permian; i.e., early Carboniferous (~ 351 Ma), early late Carboniferous (~ 319 Ma), and early Permian (295–293 Ma). The early Carboniferous rhyolites exhibit chemical affinities to A-type rhyolites, implying an extensional environment. Their positive εHf(t) values (+ 8.67 to + 13.4 except for one spot of + 1.63) and Hf two-stage model ages (TDM2 = 562–988 Ma) indicate that the primary magma was possibly derived from partial melting of newly accreted continental crust. The early late Carboniferous rhyolites and dacites (~319 Ma) exhibit calc-alkaline peraluminous signature [molar Al2O3/(CaO + K2O + Na2O) ratio, or A/CNK = 1.04–1.22]. The εHf(t) values and TDM2 ages of zircons from the 319 Ma dacites are in the range of +5.33 to +9.32 and 907–1268 Ma, respectively, suggesting that the primary magma was derived from partial melting of newly accreted crust. The early Permian rhyolites (295–293 Ma) show chemical affinities to A-type rhyolites, implying an extensional tectonic environment; their positive εHf(t) values (+8.82 to +13.8) and Hf two-stage model ages (484–743 Ma) indicate that the primary magma was derived from partial melting of newly accreted crust. Combined with the geochemical features of coeval igneous rocks from the eastern margin of the Xing'an Massif, these data reveal the late Paleozoic tectonic history and relationships of the Xing'an and Songnen–Zhangguangcai Range massifs, i.e., early Carboniferous westward subduction of the Paleo-Asian oceanic plate beneath the Xing'an Massif, followed by early late Carboniferous collision and amalgamation of microcontinental blocks, and early Permian post-collisional extension. © 2014 Elsevier B.V. All rights reserved.

1. Introduction Tectonically, northeast (NE) China has traditionally been considered as the eastern segment of the Central Asian Orogenic Belt (CAOB), located between the Siberian and the North China cratons (Jahn et al., 2000; Li, 2006; Sengör et al., 1993; Windley et al., 2007; Xiao et al., 2004). The Paleozoic tectonic evolution of NE China was dominated by the amalgamation of multiple microcontinental massifs (including, from west to east, the Erguna, Xing'an, Songnen–Zhangguangcai Range, Jiamusi,

⁎ Corresponding author at: 2199 Jianshe Street, College of Earth Sciences, Jilin University, Changchun 130061, China. Tel./fax: +86 431 88502080. E-mail addresses: [email protected] (Y. Li), [email protected] (W.-L. Xu), [email protected] (F. Wang), [email protected] (J. Tang), [email protected] (F.-P. Pei), [email protected] (Z.-J. Wang).

http://dx.doi.org/10.1016/j.lithos.2014.07.008 0024-4937/© 2014 Elsevier B.V. All rights reserved.

and Khanka massifs) (Sengör et al., 1993) and the closure of the Paleo-Asian ocean, whereas the Mesozoic tectonic evolution of the area was characterized by overprinting of the circum-Pacific system in the east and the Mongol–Okhotsk system in the northwest (Meng et al., 2010, 2011; Tang et al., 2014; Wang et al., 2012; Wu et al., 2007; Xu et al., 2009, 2013). However, the timing of the amalgamation of the massifs during the Paleozoic remains controversial (Cui et al., 2013; Li, 2006; Meng et al., 2010; Miao et al., 2007; Sorokin et al., 2004; Wang et al., 2012; Wilde et al., 2003; Windley et al., 2007; Xiao et al., 2004). For example, the amalgamation between the Xing'an and Songnen– Zhangguangcai Range massifs has been assigned to the Late Devonian (Su, 1996), the Late Devonian–early Carboniferous (Hong et al., 1994; Tang et al., 2011), the late early Carboniferous (Cui et al., 2013; Liu et al., 2012; Zhao et al., 2010a), the pre-Permian (Shi et al., 2004; Sun et al., 2000; Tong et al., 2010), and the Triassic (Chen et al., 2000;

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Miao et al., 2003). Controversies have arisen because of a lack of precise dating and detailed geochemical data for the Paleozoic igneous rocks in both the Xing'an and Songnen–Zhangguangcai Range massifs. In recent years, a large amount of geochronological and geochemical data has been obtained for intrusive rocks from NE China, especially for granites (Jahn et al., 2000; Wang et al., 2012; Wu et al., 2002, 2011; Xu et al., 1999). In contrast, few studies have examined Paleozoic volcanic rocks in the region. In the present study, therefore, we undertook zircon U–Pb dating and geochemical analyses of early Carboniferous–early Permian volcanic rocks that outcrop on the western margin of the Songnen–Zhangguangcai Range Massif, which is adjacent to the Heihe–Nenjiang suture zone. Our data, combined with data from late Paleozoic igneous rocks in the Xing'an Massif, reveal the tectonic evolution and relationships of the Xing'an and Songnen–Zhangguangcai Range massifs during the early Carboniferous–early Permian.

2. Geological background and sample descriptions NE China, located in the eastern section of the CAOB, includes the Erguna and Xing'an massifs in the northeast, the Songnen– Zhangguangcai Range Massif in the center, and the Jiamusi and Khanka massifs in the east, with the various massifs separated by major faults. The present study area is situated on the western edge of the Songnen–Zhangguangcai Range Massif; geographically, the region is in the Sunwu area, Heilongjiang Province, NE China, which is adjacent to the Heihe–Nenjiang suture zone, which represents the final amalgamation between the Xing'an and Songnen–Zhangguangcai Range massifs. The Songnen–Zhangguangcai Range Massif is made up mainly of the Songliao Basin and the Lesser Xing'an–Zhangguangcai Ranges. The Songliao Basin formed during the late Mesozoic, based on the geochronology of basement rocks in the basin, which consist of weakly deformed and metamorphosed Phanerozoic granites and Paleozoic strata (Meng et al., 2011; Wang et al., 2014; Wu et al., 2011). The strata outcropping on the western margin of the Songnen–Zhangguangcai Range Massif include the Middle Devonian Fuxingtun Formation (D2f), lower Carboniferous Kunaerhe Formation (C1k), upper Carboniferous Hetaoshan Formation (C3h), middle Permian Wudaoling Formation (P2w), upper Jurassic Tamulangou (J3t) and Shangkuli (J3sh) formations, and lower Cretaceous Jiufengshan (K1j) and Ganhe (K1g) formations. In addition, voluminous Paleozoic and Mesozoic granitoids, known as the “granite ocean”, occur in the study area and adjacent areas (HBGMR, 1987, 1991, 1993; Wu et al., 2011). The volcanic rocks in this study were collected from the Kunaerhe, Hetaoshan, and Wudaoling formations (Fig. 1b–d). The Kunaerhe Formation (C1k), previously thought to be early Carboniferous in age, is composed mainly of intermediate–acidic volcanic rocks, silty slate, and fine sandstone. The Hetaoshan Formation (C3h), previously thought to be late Carboniferous in age, consists mainly of rhyolites and dacites. The Wudaoling Formation (P2w), previously thought to be middle Permian in age, is composed mainly of rhyolites, dacites, and silty slate (HBGMR, 1987, 1991). In the present study, samples HSW10 (13HSW3), HSW4, HSW5, 12HSW4 (13HSW5), and HSW8 (13HSW1) are from volcanic rocks previously mapped as Carboniferous–Permian in age. Note that sample numbers (e.g., HSW5) represent locations; if more than one sample was collected from a given location, the samples are labeled with a sequence of numbers (e.g., HSW5-1); some samples in parentheses were collected in the same location in different years [e.g., HSW10 (13HSW3)]. The summary of the early Carbiniferous–early Permian volcanic rocks is shown in Table 1. Sample HSW10 (13HSW3) was collected from rocks previously mapped as the early Carboniferous Kunaerhe Formation in a 1:200,000 regional geological survey (HBGMR, 1991). The sample was collected from near Qilingang (49°58′41.3″N, 127°06′59.8″E). The rhyolites have porphyritic textures and rhyolitic structures (Fig. 2a, b). The phenocrysts (25% by volume, vol) consist of quartz (~6%), sanidine (~12%), and

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plagioclase (~7%); the groundmass (75% by vol) is composed of aphanitic felsic minerals with minor opaque minerals. Rhyolite sample HSW4 and dacite sample HSW5 were collected from the Wudaoling Formation, which was previously mapped as middle Permian in age during a 1:200,000 regional geological survey (HBGMR, 1987). The samples were collected from near Chenqing (49°02′24.7″N, 127°02′14.0″E and 49°02′51.9″N, 127°02′14.0″E, respectively). Sample HSW4 is dark gray in color and exhibits porphyritic textures and rhyolitic structures. The phenocrysts (35% by vol) consist of quartz (~ 8%), sanidine (13%–15%), and plagioclase (12%–14%); the groundmass (65% by vol) is composed of aphanitic felsic material. Sample HSW5 is also dark gray in color and exhibits porphyritic textures and rhyolitic structures. The phenocrysts (30% by vol) consist of quartz (~8%), sanidine (8%), and plagioclase (~14%); the groundmass (70% by vol) is composed of aphanitic felsic minerals (Fig. 2c, d). Sample 12HSW4 (13HSW5) was collected from the Wudaoling Formation, which was previously mapped as middle Permian in age during a 1:200,000 regional geological survey (HBGMR, 1987). The sample was collected from the south of Qingxi (49°19′32.0″N, 127°08′ 32.6″E). The rhyolite is dark gray in color with spherulitic textures and rhyolitic structures (Fig. 2e, f). The phenocrysts (20% by vol) are quartz (~5%), sanidine (~9%), and plagioclase (~6%); the groundmass (80% by vol) is composed of aphanitic felsic minerals with opaque minerals. Sample HSW8 (13HSW1) was collected from the Hetaoshan Formation, which was mapped previously as late Carboniferous in age (HBGMR, 1991). The sample was collected from a site ~ 12 km along the highway from Songshugou to Qilingang (49°58′32.8″N, 127°10′58.0″E). The sample is gray in color and with porphyritic texture and massive structure. The phenocrysts (20% by vol) are quartz (~ 5%), sanidine (~ 9%), and plagioclase (~ 6%); the groundmass (80% by vol) is composed of aphanitic felsic minerals with minor opaque minerals. 3. Analytical methods 3.1. Zircon U–Pb dating Zircons were separated from whole-rock samples using the conventional heavy liquid and magnetic techniques, and then by handpicking under a binocular microscope, at the Langfang Regional Geological Survey, Hebei Province, China. The handpicked zircons were examined under transmitted and reflected light with an optical microscope. To reveal their internal structures, cathodoluminescence (CL) images were obtained using a JEOL scanning electron microscope housed at the State Key Laboratory of Continental Dynamics, Northwest University, Xi'an, China. Distinct domains within the zircons were selected for analysis, based on the CL images. LA-ICP-MS zircon U–Pb analyses were performed using an Agilent 7500a ICP-MS equipped with a 193 nm laser, housed at the State Key Laboratory of Geological Processes and Mineral Resources, China University of Geosciences, Wuhan, China. The zircon 91500 was used as an external standard for age calibration, and the NIST SRM 610 silicate glass was applied for instrument optimization. The crater diameter was 32 μm during the analyses. The instrument parameter and detail procedures were described by Yuan et al. (2004). The ICPMSDataCal (Ver. 6.7; Liu et al., 2008, 2010) and Isoplot (Ver. 3.0; Ludwig, 2003) programs were used for data reduction. Correction for common Pb was made following Anderson (2002). Errors on individual analyses by LA-ICP-MS are quoted at the 1σ level, while errors on pooled ages are quoted at the 95% (2σ) confidence level. The dating results are presented in Supplementary Table 1. 3.2. Major and trace element determinations For geochemical analysis, whole-rock samples, after the removal of altered surfaces, were crushed in an agate mill to ~ 200 mesh. X-ray

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Table 1 Summary of the early Carboniferous–early Permian volcanic rocks. Sample No.

HSW10 and 13HSW3 HSW4 HSW5 12HSW4 and 13HSW5 HSW8 and 13HSW1

Location

49°58′41.3″N 127°06′59.8″E 49°02′24.7″N 127°02′14.0″E 49°02′51.9″N 127°02′14.0″E 49°19′32.0″N 127°08′32.6″E 49°58′32.8″N 127°10′58.0″E

Lithology

Formation

Texture/structure

Rhyolite

Kunaerhe Formation

Rhyolite

Wudaoling Formation

Dacite

Wudaoling Formation

Rhyolite

Wudaoling Formation

Rhyolite

Hetaoshan Formation

Porphyritic texture rhyolitic structure Porphyritic texture rhyolitic structure Porphyritic texture rhyolitic structure Spherulitic texture rhyolitic structure Porphyritic texture rhyolitic structure

Phenocryst (vol.%)

Groundmass (vol.%)

Q

San

Pl

6

12

7

75

8

13–15

12–14

65

8

8

14

70

5

9

6

80

5

9

6

80

Note: Pl—plagioclase; Q—quartz; San—sanidine.

fluorescence (XRF; Rigaku RIX 2100 spectrometer) using fused-glass disks and ICP-MS (Agilent 7500a with a shield torch) was used to measure the major and trace element compositions, respectively, at the State Key Laboratory of Geological Processes and Mineral Resources, China University of Geosciences (Wuhan), after acid digestion of samples in Teflon bombs. Analytical uncertainties are in the range 1%–3%. The analytical results for the BHVO-1 (basalt), BCR-2 (basalt), and AGV-1 (andesite) standards indicate that the analytical precision for major elements is better than 5%, and for trace elements, generally better than 10% (Rudnick et al., 2004). The analytical results of major and trace elements of the early Carboniferous to early Permian volcanic rocks are listed in Table 2. 3.3. Hf isotope analyses In situ zircon Hf isotope analyses were conducted using a Neptune Plus MC-ICP-MS (Thermo Fisher Scientific, Germany) in combination with a Geolas 2005 excimer ArF laser ablation system (193 nm) that was hosted at the state Key Laboratory of Geological Processes and Mineral Resources, China University of Geosciences in Wuhan. We used a simple Y junction downstream from the sample cell to add small amounts of nitrogen (4 ml min−1) to the argon makeup gas flow (Hu et al., 2008a,b). Compared with the standard arrangement, the addition of nitrogen in combination with the use of a newly designed X skimmer cone and Jet sample cone in Neptune Plus, improved the signal intensities of Hf, Yb, and Lu by factors of 5.3, 4.0, and 2.4, respectively. All data were acquired on zircon in single spot ablation mode with a spot size of 44 μm. Each measurement consisted of 20 s of acquisition of the background signal followed by 50 s of acquisition of the ablation signal. For details of the operating conditions for the laser ablation system and the MC-ICP-MS instrument, as well as the analytical method, see Hu et al. (2012). Present-day chondritic ratios of 176Hf/177Hf = 0.282772 and 176 Lu/177 Hf = 0.0332 (Blichert-Toft and Albarède, 1997) were used to calculate εHf(t) values, and Hf model ages were calculated using the methods of Amelin et al. (2000), Griffin et al. (2000), and Nowell et al. (1998). The results of Hf isotope analyses for the early Carboniferous to early Permian volcanic rocks are presented in Table 3. 4. Analytical results 4.1. Zircon U–Pb dating The zircons selected for analysis are euhedral–subhedral and display fine-scale oscillatory growth zoning in cathodoluminescence

(CL) images (Fig. 3). These properties, together with their high Th/U ratios (0.10–1.71; Supplementary Table 1), indicate that the zircons are of magmatic origin (Koschek, 1993; Pupin, 1980). Sample HSW10, a rhyolite, was collected from the Kunaerhe Formation, previously mapped as early Carboniferous in age (HBGMR, 1991). The 206Pb/238U ages of 11 analytical spots range from 350 to 352 Ma, yielding a weighted mean 206Pb/238U age of 351 ± 3 Ma [mean square weighted deviation (MSWD) = 0.04, n = 11] (Fig. 4a), which is interpreted to represent the crystallization age of the rhyolite. Sample HSW4-1, a rhyolite, was collected from the Wudaoling Formation, previously mapped as middle Permian in age. Zircons from this sample are euhedral–subhedral in shape, and exhibit an inherited core overgrown by a rim with oscillatory growth zoning (Fig. 3b). The 206 Pb/238U ages of 22 analytical spots from the rhyolite (HSW4) range from 317 to 352 Ma, yielding three groups of concordant ages: 319 ± 3 Ma (MSWD = 0.05, n = 6), 335 ± 2 Ma (MSWD = 0.17, n = 13), and 351 ± 4 Ma (MSWD = 0.02, n = 3) (Fig. 4b). The youngest age (319 Ma) represents the crystallization age of the rhyolite (i.e., early late Carboniferous, rather than middle Permian as previously reported by HBGMR, 1987, 1993). Other ages (335 and 351 Ma) represent the crystallization age of inherited or captured zircons entrained by the rhyolite. Sample HSW5-5, a dacite, was collected from the Wudaoling Formation, previously mapped as middle Permian in age. The 206 Pb/238U ages of 24 analytical spots from the rhyolite (HSW5-5) range from 319 to 354 Ma, yielding three groups of concordant ages (Fig. 4c): 319 ± 2 Ma (MSWD = 0.18, n = 10), 335 ± 2 Ma (MSWD = 0.42, n = 7), and 349 ± 3 Ma (MSWD = 0.72, n = 7), which are the same as the ages of the rhyolite (HSW4). The youngest age (319 Ma) represents the crystallization age of the rhyolite (i.e., early late Carboniferous, rather than middle Permian as reported by HBGMR, 1987, 1993). Other ages (335 and 351 Ma) represent the crystallization ages of inherited or captured zircons entrained by the dacite. Sample 12HSW4, a rhyolite, was collected from the Wudaoling Formation, previously mapped as middle Permian in age. The 206Pb/238U ages of 23 analytical spots from the rhyolite (12HSW4) range from 287 to 320 Ma, yielding two groups of concordant ages (Fig. 4d): 295 ± 2 Ma (MSWD = 0.12, n = 18) and 318 ± 5 Ma (MSWD = 0.08, n = 5). The age of 295 Ma represents the crystallization age of the rhyolite (i.e., early Permian, rather than middle Permian as reported by HBGMR, 1987, 1993), while the age of 318 Ma represents the crystallization age of inherited or captured zircons entrained by the rhyolite.

Fig. 1. (a) Tectonic sketch map of northeast China, modified after Wu et al. (2007). 1: Mudanjiang Fault; 2: Dunhua–Mishan Fault; 3: Yitong–Yilan Fault; 4: Solonker–Xra Moron– Changchun Fault; 5: Hegenshan–Heihe Fault; 6: Xiguitu–Tayuan Fault; 7: Mongol–Okhotsk suture belt. (b) Detailed geological map of the study area in the Songnen–Zhangguangcai Range Massif. (c) and (d) Enlargement of an area in (b), showing the locations of samples examined in this paper.

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Sample HSW8, a rhyolite, was collected from the Hetaoshan Formation, previously mapped as late Carboniferous in age. The 206Pb/ 238 U ages of 24 analytical spots from the rhyolite (HSW8) range from 293 to 362 Ma, yielding two groups of concordant ages (except for one spot, 362 Ma; Fig. 4e): 293 ± 2 Ma (MSWD = 0.45, n = 18) and 317 ± 4 Ma (MSWD = 0.15, n = 5). The former (293 Ma) represents the crystallization age of the rhyolite (i.e., early Permian, rather than late Carboniferous as reported by

HBGMR, 1991, 1993), while the latter age (317 Ma) represents the crystallization age of inherited or captured zircons entrained by the rhyolite. The LA-ICP-MS zircon U–Pb dating results indicate that early Carboniferous–early Permian magmatic events in our study area can be subdivided into at least three stages (Fig. 4f): early Carboniferous (~ 351 Ma), early late Carboniferous (~ 319 Ma), and early Permian (295–293 Ma).

Fig. 2. Representative photographs of early Carboniferous–early Permian volcanic rocks from the Songnen–Zhangguangcai Range Massif, NE China, showing textures and internal structures. (a) early Carboniferous rholite (Sample HSW10-2, single polarized light); (b) early Carboniferous rhyolite (Sample HSW10-2, crossed polarized light); (c) early late Carboniferous rholite (Sample HSW4-2, single polarized light); (d) early late Carboniferous dacite (Sample HSW5-4, crossed polarized light); (e) early Permian rhyolite (Sample 12HSW4, crossed polarized light); (f) early Permian rhyolite (Sample 12HSW4, crossed polarized light). Pl — plagioclase; San — sanidine.

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4.2. Major and trace elements The major and trace element geochemical data for early Carboniferous–early Permian volcanic rocks in the study area are listed in Table 2. 4.2.1. Early Carboniferous volcanic rocks The compositions of early Carboniferous volcanic rocks are: SiO2 = 75.76–79.18 wt.%, TiO2 = 0.17–0.26 wt.%, Al2O3 = 11.691– 3.29 wt.%, total Fe 2 O3 = 1.49–2.62 wt.%, CaO = 0.64–1.52 wt.%, Na 2O = 0.95–2.00 wt.%, K 2O = 4.45–5.62 wt.%, and Na 2 O/K 2O = 0.17–0.45 (Table 2). On a TAS diagram of total alkalis versus SiO 2 (Fig. 5a; Irvine and Baragar, 1971), the samples plot in the sub-alkaline series. On a K2O versus SiO2 diagram (Fig. 5b; Peccerillo and Taylor, 1976), the sample plot in a high-K calc-alkaline series; their A/CNK ratios of 1.16–1.42 correspond to peraluminous rocks on an A/NK versus A/CNK diagram (Fig. 5c; Maniar and Piccoli, 1989). The early Carboniferous volcanic rocks are enriched in light rare earth elements (LREEs) and large ion lithophile elements (LILEs; e.g., Rb, Ba, and K), depleted in heavy rare earth elements (HREEs) (LREE/HREE = 5.54–6.84, (La/Yb) N = 4.81–6.46) and high field strength elements (HFSEs), such as Nb, Ta, Ti, and P, and exhibit strongly negative Eu anomalies (δEu = 0.16–0.24) (Fig. 6a, b; Table 2). 4.2.2. Early late Carboniferous volcanic rocks The compositions of early late Carboniferous volcanic rocks are: SiO2 = 69.05–80.13 wt.%, TiO2 = 0.14–0.59 wt.%, Al2O3 = 11.92– 16.24 wt.%, total Fe2O3 = 0.56–3.08 wt.%, CaO = 0.20–2.01 wt.%, Na2O = 3.05–5.77 wt.%, K2O = 1.73–6.09 wt.%, and Na2O/K2O = 0.50–3.33 (Table 2). Chemically, these rocks belong to a sub-alkaline series (Fig. 5a) and a medium- to high-K calc-alkaline series. Their A/ CNK ratios of 1.04–1.22 correspond to peraluminous on an A/NK versus A/CNK diagram (Fig. 5c; Maniar and Piccoli, 1989). The early late Carboniferous volcanic rocks are enriched in LREEs and LILEs, depleted in HREEs and HFSEs, and exhibit weakly negative Eu anomalies (Fig. 6c, d). Their LREE/HREE ratios range from 10.9 to 13.4, and their (La/Yb)N and δEu values range from 9.66 to 16.0 and 0.60 to 1.04, respectively. 4.2.3. Early Permian volcanic rocks The compositions of early Permian volcanic rocks are: SiO2 = 66.34–76.33 wt.%, TiO2 = 0.14–0.41 wt.%, Al2O3 = 13.28–17.29 wt.%, total Fe2O3 = 0.24–3.99 wt.%, CaO = 0.21–1.77 wt.%, Na2O = 3.74–6.55 wt.%, K2O = 2.63–4.80 wt.%, and Na2O/K2O = 0.81–1.95 (Table 2). Chemically, the rocks belong to a high-K calc-alkaline series (Fig. 5a; Irvine and Baragar, 1971; Fig. 5b; Peccerillo and Taylor, 1976). Their A/CNK ratios of 0.99–1.48 correspond to metaluminous to peraluminous on an A/NK versus A/CNK diagram (Fig. 5c; Maniar and Piccoli, 1989). The early Permian volcanic rocks are enriched in LREEs and LILEs, depleted in HREEs and HFSEs, and exhibit negative Eu anomalies (δEu = 0.24–1.08). Their LREE/HREE and (La/Yb) N ratios range from 5.74 to 9.18 and 4.79 to 8.27, respectively (Fig. 6e, f; Table 2). 4.3. Zircon Hf isotopes Some of the U–Pb dating spots on zircons from samples HSW10-1, HSW5-5, 12HSW4-1, and HSW8-1 were chosen for in situ Hf isotope analysis; analytical results are given in Table 3 and are shown in Fig. 7. 4.3.1. Early Carboniferous volcanic rocks The initial 176Hf/177Hf ratios of zircons from the early Carboniferous rhyolite (sample HSW10-1, 351 Ma) range from 0.282608 to 0.282948. The εHf(t) values and two-stage modal ages (TDM2) range

399

from + 8.67 to + 13.4 and 562 to 988 Ma, respectively (except for one spot with an ε Hf(t) value of + 1.63 and a T DM2 of 1622 Ma; Table 3). 4.3.2. Early late Carboniferous volcanic rocks The initial 176Hf/177Hf ratios of zircons from the early late Carboniferous dacite (Sample HSW5-5, 319 Ma) vary from 0.282734 to 0.282832. The εHf(t) values and TDM2 ages range from +5.33 to +9.32 and 907 to 1268 Ma, respectively. The εHf(t) values of captured zircons with an age of 335 Ma range from +6.60 to +7.58, and the corresponding TDM2 age ranges from 1075 to 1164 Ma. The εHf(t) values and TDM2 ages of captured zircons with an age of 349 Ma in this sample range from +6.55 to +8.13 and 1035 to 1178 Ma, respectively (Table 3). 4.3.3. Early Permian volcanic rocks The initial 176 Hf/ 177 Hf ratios for primary zircons with ages of 295–293 Ma from samples 12HSW4-1 and HSW8-1 range from 0.282845 to 0.282999. Their ε Hf (t) values and T DM2 ages range from +8.82 to +13.8 and 484 to 743 Ma, respectively. The εHf(t) values of the captured zircons with ages of 318–317 Ma range from +8.84 to + 13.6, and their corresponding TDM2 ages range from 520 to 712 Ma. The εHf(t) value and TDM2 age of a captured zircon with an age of 362 Ma from sample HSW8-1 are +13.3 and 575 Ma, respectively (Table 3). 5. Discussion 5.1. Early Carboniferous to early Permian magmatic events in the Xing'an and Songnen–Zhangguangcai Range massifs The samples analyzed in this study (including the rhyolites and dacites) were collected from the previously mapped lower Carboniferous Kunaerhe Formation, upper Carboniferous Hetaoshan Formation, and middle Permian Wudaoling Formation; the ages of these units were originally assigned on the basis of lithostratigraphic relationships and regional comparisons (HBGMR, 1987, 1991, 1993). However, the ages of these strata have been controversial due to a lack of precise geochronological data, and later over-printing by multiple tectonic– magmatic thermal events. Recently, the application of new zircon U– Pb dating methods, such as LA-ICP-MS, sensitive high-resolution ion microprobe (SHRIMP) analysis, and secondary ion mass spectrometry (SIMS), has yielded information that terranes previously identified as early Paleozoic or Precambrian in age are actually late Paleozoic or early Mesozoic in age (Wang et al., 2012; Wu et al., 2011). The revised ages based on these precise zircon U–Pb dating methods suggest that zircon U–Pb dating is currently the best approach for determining the ages of igneous rocks in the study area. Zircons from the studied samples exhibit oscillatory growth zoning and high Th/U ratios (0.10–1.71), indicative of a magmatic origin, suggesting that the U–Pb ages obtained from the zircons represent the timing of crystallization of the zircon host rocks. Fig. 4a–e shows that most of the 207Pb/235U ages of these zircons plot away from the concordia, which may reflect errors in the 207Pb measurements due to low 207Pb contents. In contrast, the consistent 206Pb/238U ages yield a very low MSWD, indicating that these ages are reliable and represent the timing of extrusion of the volcanic rocks. Zircon U–Pb dating indicates that early Carboniferous–early Permian magmatic events in the study area can be subdivided into three stages: early Carboniferous (~ 351 Ma), early late Carboniferous (~ 319 Ma), and early Permian (295–293 Ma). In addition to the early Carboniferous rhyolites of the Songnen– Zhangguangcai Range Massif examined in this study, early Carboniferous magmatic events are also widespread in the Xing'an Massif along the Heihe–Nenjiang suture zone. Early Carboniferous volcanic rocks with zircon U–Pb ages of 355–351 Ma are dominant on the eastern margin of the Xing'an Massif (Liu et al., 2012; Zhao

400

Y. Li et al. / Lithos 205 (2014) 394–410

Table 2 Major (wt.%) and trace elements (ppm) data for the early Carboniferous–early Permian volcanic rocks. Sample

HSW10-2

Age

Early Carboniferous

HSW10-3

SiO2 TiO2 Al2O3 TFe2O3 MnO MgO CaO Na2O K2O P2O5 LOI Total Na2O + K2O Na2O/K2O A/CNK Sc V Cr Co Ni Ga Rb Sr Y Zr Nb Ba La Ce Pr Nd Sm Eu Gd Tb Dy Ho Er Tm Yb Lu Hf Ta Pb Th U δEu ∑LREE/∑HREE (La/Yb)N

77.51 0.20 11.44 1.46 0.05 0.10 0.77 1.95 4.36 0.05 1.92 99.81 6.45 0.45 1.23 5.88 1.46 1.29 0.27 0.34 14.8 95.6 179 55.2 481 21.7 320 42.7 89.1 11.0 43.3 8.58 0.54 8.65 1.51 9.29 1.87 5.31 0.81 5.62 0.81 11.7 1.44 12.7 13.5 4.48 0.19 5.76 5.12

74.63 0.16 11.95 1.77 0.04 0.12 0.61 0.91 5.37 0.04 3.96 99.56 6.57 0.17 1.42 4.67 4.23 1.42 0.14 0.32 26.6 134 140 72.0 454 24.2 385 50.1 97.1 11.9 46.3 9.19 0.49 9.10 1.58 10.36 2.23 6.44 1.03 7.02 1.04 11.4 1.52 5.24 14.4 5.12 0.16 5.54 4.81

13HSW3-1

13HSW3-2

13HSW3-4

13HSW3-7

HSW4-1

HSW4-2

HSW4-4

HSW5-4

HSW5-5

Early late Carboniferous 73.50 0.24 12.38 2.37 0.08 0.17 1.25 1.40 4.84 0.03 3.34 99.60 6.48 0.29 1.26 7.25 3.37 1.88 0.23 0.43 18.6 108 244 47.8 414 22.5 362 43.1 95.2 10.7 40.9 8.42 0.66 8.26 1.36 8.52 1.71 4.86 0.71 4.82 0.73 10.5 1.46 8.44 13.4 4.46 0.24 6.42 6.03

73.11 0.25 12.82 2.53 0.08 0.17 1.12 1.56 4.84 0.02 3.26 99.76 6.63 0.32 1.30 7.93 3.60 2.03 0.18 0.44 19.3 108 223 50.5 443 23.6 338 46.2 99.0 11.6 44.8 10.0 0.71 9.17 1.44 8.96 1.81 4.80 0.72 4.82 0.71 10.9 1.51 9.31 13.6 4.47 0.22 6.55 6.46

73.95 0.24 12.15 2.07 0.08 0.15 1.47 1.48 4.86 0.03 3.36 99.83 6.57 0.30 1.17 7.74 3.42 2.24 0.40 0.74 17.4 105 275 51.3 443 23.2 355 48.0 113 12.7 50.8 11.5 0.84 10.0 1.56 9.36 1.84 5.14 0.77 5.16 0.78 11.0 1.54 10.3 13.5 4.91 0.23 6.84 6.27

74.38 0.23 12.04 2.24 0.07 0.15 1.18 1.94 4.64 0.03 2.94 99.84 6.79 0.42 1.16 7.20 3.16 2.25 0.38 0.56 15.9 99.2 252 51.0 423 22.5 363 45.0 101 11.7 44.6 9.36 0.69 8.75 1.42 8.91 1.78 5.08 0.74 4.83 0.74 11.0 1.45 11.4 13.5 5.01 0.23 6.58 6.28

77.73 0.14 11.56 0.54 0.04 0.24 0.19 3.73 2.79 0.04 3.03 100.03 6.72 1.34 1.22 1.58 2.97 0.50 0.30 1.06 11.4 82.7 130 12.9 118 16.5 883 21.6 43.2 4.45 14.4 2.33 0.50 2.15 0.33 1.88 0.40 1.22 0.20 1.45 0.22 3.36 1.43 9.01 11.8 2.65 0.67 11.0 10.1

78.23 0.15 13.26 0.64 0.04 0.52 0.34 5.33 2.23 0.03 0.01 100.78 7.50 2.39 1.12 1.66 3.12 0.51 0.44 1.41 14.1 78.7 165 13.3 120 18.1 457 20.9 41.3 4.28 13.2 2.03 0.39 1.88 0.30 1.82 0.41 1.25 0.21 1.46 0.23 3.50 1.55 8.17 12.8 2.76 0.60 10.9 9.66

75.85 0.16 13.47 0.67 0.03 0.20 0.24 3.04 6.07 0.02 0.21 99.96 9.13 0.50 1.12 1.70 3.18 0.32 0.53 2.35 14.8 133 192 13.8 140 20.1 1348 32.3 53.7 5.29 16.5 2.43 0.60 2.06 0.34 2.04 0.43 1.32 0.23 1.61 0.26 4.04 1.73 12.0 14.2 3.94 0.80 13.4 13.5

12HSW4-1

12HSW4-3

Early Permian 69.05 0.57 15.45 2.95 0.09 0.97 1.98 5.69 1.71 0.16 1.08 99.70 7.50 3.33 1.04 6.27 46.4 9.03 8.35 9.41 13.5 42.8 410 14.2 152 16.5 412 32.5 53.5 5.68 19.5 3.37 0.99 3.01 0.44 2.53 0.49 1.35 0.20 1.37 0.20 3.84 1.44 12.9 10.4 2.70 0.93 12.0 16.0

67.88 0.58 15.96 3.03 0.08 1.02 1.38 5.48 2.73 0.16 1.42 99.72 8.35 2.01 1.10 6.48 56.5 8.18 8.95 10.3 14.8 74.3 379 13.1 141 16.5 768 26.3 48.2 5.06 17.9 3.21 1.04 2.76 0.42 2.37 0.47 1.29 0.22 1.36 0.21 3.60 1.47 14.0 10.4 3.02 1.04 11.2 13.0

67.53 0.40 15.54 3.76 0.11 0.68 1.67 5.36 3.52 0.10 0.76 99.43 9.00 1.52 0.99 23.5 24.20 4.72 3.17 1.39 19.3 67.8 158 30.8 274 10.8 2233 27.6 59.3 7.20 28.6 6.50 1.99 5.49 0.84 5.13 1.06 3.06 0.48 3.30 0.48 6.55 0.68 19.0 7.57 2.46 0.99 6.61 5.64

73.20 0.17 13.71 2.24 0.08 0.29 0.94 4.52 3.86 0.03 0.76 99.79 8.46 1.17 1.03 8.88 10.4 2.75 1.47 1.18 20.6 94.3 68.7 40.5 361 13.5 463 37.1 77.8 9.22 36.2 7.72 0.70 6.71 1.08 6.60 1.38 4.05 0.61 4.25 0.65 9.01 0.88 21.3 11.0 3.22 0.29 6.66 5.89

Note: LOI: Loss on ignition; A/CNK = mole [Al 2O 3 /(CaO + Na 2O + K 2O)]; δEu = (Eu)cn/[(Gd)cn + (Sm)cn]/2.LREE = La + Ce + Pr + Nd + Sm + Eu; HREE = Gd + Tb + Dy + Ho + Er + Tm + Yb + Lu; (La/Yb)N = (La/0.310)/(Yb/0.209).

et al., 2010a). In addition, early Carboniferous granodiorite (354 Ma, Rb–Sr isochron method) in the Wunuer area (Xu et al., 1999), adamellite (352 Ma, SHRIMP) and syengranite (345 Ma) in the Huolongmen area (Li et al., 2013), and quartz diorite (351 Ma) in the Yinhe area (Zhao et al., 2010b) have also been recognized in the Xing'an Massif. Early late Carboniferous magmatic events occur mainly in the Xing'an Massif, aside from minor rhyolites that occur in the Songnen– Zhangguangcai Range Massif (Wang et al., 2014). For example, early late Carboniferous intrusive rocks include granitic mylonite (325 Ma) in Nenjiang (Wang et al., 2013), granodiorite (319 Ma) and adamellite (316 Ma) in the Longzhen area (Zhang et al., 2010), syenogranite (322 Ma) in the Quanshenglinchang area (Cui et al., 2013), and granitic gneiss (320 Ma) and syenogranite (322 Ma) in the Zhalantun area (Gao et al., 2013).

Early Permian magmatism is widespread in both the Xing'an and Songnen–Zhangguangcai Range massifs. Early Permian magmatic events produced mainly bimodal volcanic rocks with minor rhyolites in the Sunwu area in the Songnen–Zhangguangcai Range Massif (Meng et al., 2011), whereas coeval magmatic events in the Xing'an Massif produced mainly A-type granites with minor basaltic rocks (Hong et al., 1994; Shi et al., 2004; Sun et al., 2000; Wu et al., 2002, 2011; Zhang et al., 2013; Zhu et al., 2001). 5.2. Magma sources for early Carboniferous to early Permian volcanic rocks Major and trace element data, along with Hf isotopic compositions of zircons from these volcanic rocks, are the main clues to the nature of the magma source. Some of the present samples have high A/CNK ratios (1.16–1.42; Table 2; Fig. 5c) that are inconsistent with the absence of

Y. Li et al. / Lithos 205 (2014) 394–410

401

Table 2 Major (wt.%) and trace elements (ppm) data for the early Carboniferous–early Permian volcanic rocks. 12HSW4-6

13HSW5-2

13HSW5-4

13HSW5-8

HSW8-1

HSW8-3

HSW8-4

HSW8-5

13HSW1-1

13HSW1-2

13HSW1-5

13HSW1-7

13HSW1-8

67.55 0.41 15.47 3.94 0.12 0.73 1.75 5.29 3.47 0.11 0.84 99.68 8.86 1.52 0.99 24.3 25.7 5.82 3.71 1.53 20.5 68.8 163 30.8 273 10.7 2179 27.4 58.6 7.03 28.5 6.23 2.11 5.51 0.87 5.24 1.06 2.95 0.47 3.25 0.48 6.52 0.69 18.4 7.55 2.40 1.08 6.55 5.68

73.73 0.22 13.74 2.24 0.07 0.37 1.33 3.71 3.81 0.04 0.82 100.08 7.58 0.97 1.09 8.88 11.8 3.02 1.59 0.74 17.3 91.6 113 37.7 297 11.7 810 34.2 71.9 8.35 32.7 6.76 1.12 6.56 0.99 6.46 1.30 3.54 0.60 3.89 0.56 7.90 0.85 28.1 10.0 3.30 0.51 6.49 5.93

74.22 0.17 13.21 2.16 0.06 0.27 0.99 4.52 3.82 0.02 0.62 100.07 8.39 1.18 0.99 8.53 10.0 3.48 1.28 0.73 19.5 90.5 61.9 40.6 340 13.1 429 35.9 75.5 8.98 34.5 7.58 0.67 6.49 1.07 6.64 1.34 3.83 0.64 4.08 0.64 8.67 0.87 16.6 10.9 3.44 0.29 6.60 5.93

74.84 0.14 13.34 1.81 0.05 0.15 0.63 3.87 4.78 0.01 0.48 100.10 8.68 0.81 1.05 7.72 5.09 2.04 0.68 0.43 19.2 108 65.7 40.9 361 13.4 501 39.3 78.2 9.62 37.8 8.27 0.62 7.16 1.10 6.94 1.37 3.91 0.60 4.34 0.63 9.14 0.91 17.1 11.1 3.85 0.24 6.67 6.11

72.61 0.24 14.16 0.97 0.01 0.11 0.21 4.42 4.01 0.07 3.04 99.85 8.71 1.10 1.18 4.06 8.03 0.70 0.59 2.03 16.6 88.0 175 40.5 172 11.7 711 32.0 60.8 7.43 28.3 5.47 1.01 5.29 0.86 5.17 1.05 3.11 0.48 3.36 0.48 4.98 0.86 10.7 9.01 3.47 0.57 6.82 6.42

72.56 0.26 14.34 0.81 0.01 0.14 0.20 5.12 3.91 0.05 2.48 99.88 9.27 1.31 1.10 4.13 9.57 3.18 0.68 3.28 16.7 83.0 181 26.8 168 11.7 703 32.3 59.6 7.39 27.7 5.30 0.95 4.59 0.72 4.35 0.86 2.58 0.42 2.82 0.41 4.84 0.83 11.0 8.98 3.39 0.58 7.95 7.73

74.84 0.26 14.05 0.73 0.01 0.15 0.28 4.37 3.92 0.02 1.14 99.77 8.41 1.11 1.18 3.79 11.1 7.87 1.59 1.86 16.4 83.6 174 24.6 182 11.4 671 31.3 61.0 7.29 27.1 5.06 0.86 4.46 0.64 3.93 0.78 2.40 0.36 2.63 0.41 5.43 0.89 8.63 9.17 2.63 0.54 8.50 8.02

73.98 0.27 14.34 0.52 0.01 0.10 0.24 5.27 3.97 0.06 1.15 99.91 9.36 1.33 1.07 4.33 8.44 1.61 0.48 1.31 16.5 84.7 195 29.7 168 11.8 694 32.9 60.6 7.34 27.9 5.29 0.93 4.68 0.75 4.34 0.91 2.65 0.40 2.88 0.44 4.94 0.86 9.46 8.87 3.37 0.56 7.92 7.71

74.84 0.13 14.93 0.94 0.01 0.20 0.21 4.19 2.58 0.02 1.82 99.86 6.91 1.62 1.48 4.40 3.79 3.07 0.94 1.78 24.7 102 90.2 48.1 207 11.3 345 36.5 76.7 9.47 36.9 8.01 0.73 7.27 1.22 7.66 1.64 4.81 0.76 5.14 0.80 6.80 0.89 4.70 11.9 2.61 0.29 5.74 4.79

70.64 0.37 17.03 0.24 0.00 0.10 0.31 6.45 3.30 0.07 1.00 99.51 9.90 1.95 1.16 5.38 12.4 2.06 0.40 0.53 17.5 67.6 192 33.9 268 17.0 504 46.0 94.5 10.8 39.2 7.51 1.19 6.00 0.91 5.59 1.12 3.25 0.51 3.75 0.58 7.63 1.28 7.47 13.0 4.61 0.52 9.18 8.27

73.18 0.30 15.73 0.24 0.00 0.14 0.27 5.16 3.53 0.03 1.10 99.69 8.81 1.46 1.23 4.86 11.6 1.25 0.21 0.52 21.2 89.3 196 30.9 251 14.9 637 38.2 76.6 8.94 33.2 6.36 0.99 5.04 0.82 5.00 1.04 3.02 0.51 3.44 0.55 7.13 1.18 8.90 11.8 3.94 0.52 8.46 7.49

74.35 0.28 14.38 0.84 0.01 0.15 0.38 4.73 3.73 0.04 1.04 99.93 8.55 1.27 1.15 3.74 8.86 1.84 0.60 1.59 16.4 76.8 207 22.9 181 11.3 652 29.4 58.1 6.78 24.9 4.78 0.85 3.71 0.61 3.77 0.78 2.32 0.38 2.56 0.40 5.21 0.85 8.49 8.97 3.11 0.60 8.59 7.74

73.93 0.28 14.49 1.11 0.01 0.17 0.34 4.49 3.93 0.07 1.12 99.94 8.52 1.14 1.18 4.32 9.49 3.00 1.14 1.97 17.4 83.8 207 25.7 205 11.8 696 31.9 62.9 7.30 27.1 5.17 0.83 4.73 0.70 4.28 0.88 2.58 0.40 2.78 0.45 5.65 0.92 12.0 9.46 3.34 0.50 8.05 7.74

aluminum-rich minerals, and this discrepancy could be related to the effects of multiple thermal events in the study area (Hong et al., 1994; Tang et al., 2014; Wu et al., 2011; Xu et al., 2013). The volcanic rocks are easily affected by later thermal events, and the alkali elements such as K and Na could have been mobilized during such events, resulting in the depletion of alkalis and an erroneous classification of the rocks as peraluminous. Therefore, the A/CNK ratios of some of the samples (e.g., 1.16–1.42) do not reflect the geochemical nature of the rocks. 5.2.1. Early Carboniferous rhyolites Early Carboniferous rhyolites exhibit high SiO2 and Al2O3, and low total FeO (FeOT) and MgO concentrations, implying that the primary magma was derived from partial melting of lower crust (Barbarin, 1999; Zen, 1986). In addition, negative Eu anomalies (δEu = 0.16–0.24) suggest that plagioclase was a residual phase in the magma source. The

εHf(t) values (+8.67 to +13.4) and TDM2 ages (562 to 988 Ma) (except for one spot with an εHf(t) value of +1.63 and TDM2 age of 1622 Ma) suggest that the primary magma could be derived from partial melting of newly accreted continental crust (Fig. 7), consistent with the Hf isotopic compositions of Phanerozoic igneous rocks in the CAOB (Yang et al., 2006). 5.2.2. Early late Carboniferous rhyolites The early late Carboniferous rhyolites and dacites exhibit high SiO2 and Al2O3 concentrations, suggesting that the primary magma was originated from partial melting of lower continental crust. However, as compared with early Carboniferous rhyolites, the early late Carboniferous rhyolites exhibit lower HREE abundances and smaller negative Eu anomalies, implying that the magma source was thickened lower crust. Combined with their εHf(t) values (+ 5.33 to + 9.32) and TDM2

402

Y. Li et al. / Lithos 205 (2014) 394–410

Table 3 Lu–Hf isotopic data for the early Carboniferous–early Permian volcanic rocks. Sample no.

t (Ma)

176

Yb/177Hf

176

Lu/177Hf

HSW10-1 HSW10-1-01 HSW10-1-02 HSW10-1-03 HSW10-1-04 HSW10-1-05 HSW10-1-06 HSW10-1-07 HSW10-1-08

351 351 351 351 351 351 351 351

0.097794 0.105739 0.020620 0.033669 0.073949 0.061609 0.064604 0.050943

0.003293 0.003579 0.000744 0.001211 0.002652 0.002423 0.002538 0.001904

HSW5-5 HSW5-5-01 HSW5-5-03 HSW5-5-06 HSW5-5-07 HSW5-5-08 HSW5-5-11 HSW5-5-02 HSW5-5-04 HSW5-5-05 HSW5-5-09 HSW5-5-12 HSW5-5-10 HSW5-5-13 HSW5-5-14

319 319 319 319 319 319 335 335 335 335 335 349 349 349

0.050993 0.024775 0.045521 0.024541 0.021317 0.047188 0.048779 0.047872 0.032724 0.030676 0.026325 0.028104 0.023708 0.025225

12HSW4-1 12HSW4-1-01 12HSW4-1-02 12HSW4-1-04 12HSW4-1-05 12HSW4-1-06 12HSW4-1-07 12HSW4-1-03 12HSW4-1-08 12HSW4-1-09 12HSW4-1-10

295 295 295 295 295 295 318 318 318 318

HSW8-1 HSW8-1-01 HSW8-1-03 HSW8-1-04 HSW8-1-07 HSW8-1-09 HSW8-1-10 HSW8-1-02 HSW8-1-05 HSW8-1-06 HSW8-1-08 HSW8-1-12 HSW8-1-11

293 293 293 293 293 293 317 317 317 317 317 362

176

Hf/177Hf

2σm

εHf(t)

2σ

TDM1 (Hf) (Ma)

TDM2 (Hf) (Ma)

fLu/Hf

0.282860 0.282834 0.282827 0.282608 0.282816 0.282948 0.282893 0.282819

0.000034 0.000034 0.000022 0.000022 0.000028 0.000064 0.000031 0.000030

10.1 9.07 9.47 1.63 8.67 13.4 11.4 8.94

1.2 1.2 0.8 0.8 1.0 2.2 1.1 1.1

592 636 599 917 646 448 531 629

863 951 915 1622 988 562 741 963

−0.90 −0.89 −0.98 −0.96 −0.92 −0.93 −0.92 −0.94

0.002195 0.001034 0.001965 0.001011 0.000851 0.001785 0.002112 0.002040 0.001340 0.001243 0.001097 0.001163 0.000960 0.001019

0.282832 0.282761 0.282734 0.282787 0.282765 0.282822 0.282771 0.282726 0.282777 0.282789 0.282844 0.282754 0.282764 0.282743

0.000031 0.000018 0.000048 0.000020 0.000019 0.000027 0.000041 0.000032 0.000017 0.000017 0.000017 0.000019 0.000017 0.000017

8.80 5.56 8.48 6.90 5.33 9.32 6.65 7.58 6.93 7.38 6.60 8.13 7.28 6.55

1.1 0.7 1.7 0.7 0.7 1.0 1.4 1.1 0.6 0.6 0.6 0.7 0.6 0.6

610 730 621 676 737 585 711 672 692 673 703 654 686 716

955 1247 984 1126 1268 907 1160 1075 1134 1093 1164 1035 1112 1178

−0.93 −0.97 −0.94 −0.97 −0.97 −0.95 −0.94 −0.94 −0.96 −0.96 −0.97 −0.96 −0.97 −0.97

0.032790 0.033539 0.058371 0.047425 0.039369 0.051674 0.062424 0.050872 0.061213 0.059840

0.001028 0.000996 0.001690 0.001397 0.001297 0.001503 0.002219 0.001481 0.002087 0.002102

0.282877 0.282865 0.282893 0.282850 0.282845 0.282874 0.282894 0.282853 0.282855 0.282837

0.000020 0.000024 0.000024 0.000026 0.000028 0.000032 0.000027 0.000028 0.000031 0.000033

10.0 9.59 10.4 8.96 8.82 9.82 10.9 9.56 9.49 8.84

1.3 1.4 1.4 1.4 1.4 1.6 1.5 1.5 1.6 1.6

533 548 519 576 581 542 524 572 580 606

626 648 602 683 691 636 596 668 672 708

−0.97 −0.97 −0.95 −0.96 −0.96 −0.95 −0.93 −0.96 −0.94 −0.94

0.042389 0.041257 0.036281 0.035808 0.092123 0.067765 0.043041 0.059700 0.047417 0.062815 0.066008 0.038094

0.001677 0.001582 0.001412 0.001430 0.003508 0.002710 0.001809 0.002391 0.001995 0.002588 0.002514 0.001497

0.282960 0.282908 0.282957 0.282985 0.282999 0.282958 0.282935 0.282926 0.282971 0.282914 0.282952 0.282934

0.000043 0.000038 0.000038 0.000038 0.000062 0.000046 0.000044 0.000047 0.000034 0.000039 0.000035 0.000030

12.8 10.9 12.7 13.7 13.8 12.5 12.3 11.9 13.6 11.5 12.8 13.3

1.5 1.3 1.3 1.3 2.2 1.6 1.6 1.7 1.2 1.4 1.3 1.1

421 495 422 382 384 437 460 479 409 500 442 457

576 743 582 492 484 603 633 671 520 712 589 575

−0.95 −0.95 −0.96 −0.96 −0.89 −0.92 −0.95 −0.93 −0.94 −0.92 −0.92 −0.95

ages (907–1268 Ma), we conclude that the primary magma for the early late Carboniferous rhyolites was derived from partial melting of juvenile thickened lower crust (Fig. 7). 5.2.3. Early Permian rhyolites The high SiO2 and Al2O3 concentrations, and low FeOT and MgO concentrations of the early Permian rhyolites imply that the primary magma was originated from partial melting of lower continental crust. The positive εHf (t) values (+ 8.82 to + 13.8) and T DM2 ages (484–743 Ma) indicate that the primary magma was derived from partial melting of newly accreted continental crust of the CAOB. 5.3. Implications for the late Paleozoic tectonic evolution of the Xing'an and Songnen–Zhangguangcai Range massifs 5.3.1. Early Carboniferous subduction of the Paleozoic oceanic plate beneath the Xing'an Massif The early Carboniferous volcanic rocks in the study area consist of a suite of acidic lavas (rhyolites) with chemical affinities to A-type

rhyolites. Moreover, the rhyolites fall into the A-type granite region in plots of FeOT/MgO and K2O + Na2O/CaO versus Zr + Nb + Ce + Y (Fig. 8; Whalen et al., 1987), suggesting they formed in an extensional environment (Eby, 1992; Sylvester, 1989). To better understand the sequence of early Carboniferous tectonic events in the study area, we examined coeval magmatic events occurring on the eastern margin of the Xing'an Massif along the Heihe– Nenjiang suture zone. A suite of calc-alkaline volcanic rocks with ages of 353–352 Ma (a basalt–andesite–dacite–rhyolite assemblage) has been recognized on the eastern margin of the Xingan Massif (Liu et al., 2012; Zhao et al., 2010a). Meanwhile, calc-alkaline intrusions (including quartz diorite, granodiorite, adamellite, and syenogranite) with ages of 354–345 Ma have been found in the Xing'an Massif (Li et al., 2013; Xu et al., 1999; Zhao et al., 2010b). These calc-alkaline igneous rocks formed in an island arc or active continental margin setting (Fig. 9; Gill, 1981; Grove et al., 2003; Wilson, 1989). The spatial variation of early Carboniferous igneous rocks on the eastern margin of the Xing'an Massif and the western margin of the Songnen– Zhangguangcai Range Massif suggests that an active continental margin

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403

Fig. 3. Cathodoluminescence (CL) images of zircons selected for analysis from early Carboniferous–early Permian volcanic rocks from the Songnen–Zhangguangcai Range Massif. The numbers on these images indicate individual analysis spots, and the values below the images show zircon ages and εHf(t) values.

or island arc setting existed on the eastern margin of the Xing'an Massif, while a passive continental margin (i.e., an extensional environment) occurred on the western margin of the Songnen–Zhangguangcai Range Massif, and that westward subduction of the Paleo-Asian oceanic plate, which separated the Xing'an and Songnen–Zhangguangcai Range massifs, occurred during the early Carboniferous (Fig. 10a).

5.3.2. Early late Carboniferous continent–continent collision The timing of the amalgamation between the Xing'an and Songnen– Zhangguangcai Range massifs remains controversial, and suggested dates include the Late Silurian–Devonian (Su, 1996), Late Devonian– early Carboniferous (Hong et al., 1994; Tang et al., 2011), late early Carboniferous (Cui et al., 2013; Zhao et al., 2010a), pre-Permian (Shi et al.,

404

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Fig. 4. Zircon U–Pb concordia diagrams and a relative probability plot for early Carboniferous–early Permian volcanic rocks from the Songnen–Zhangguangcai Range Massif.

2004; Sun et al., 2000; Tong et al., 2010), and Triassic (Chen et al., 2000; Miao et al., 2003). Most scholars are now more likely to support a model of two blocks colliding in the late Paleozoic to explain the juxtaposition

of the two massifs. In this paper, the ages and compositions of early late Carboniferous volcanic rocks from the western margin of the Songnen– Zhangguangcai Range Massif and coeval igneous rocks on the eastern

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405

Fig. 5. Chemical compositions of early Carboniferous–early Permian volcanic rocks examined in this study: (a) SiO2 versus total alkali (Na2O + K2O) concentrations; (b) SiO2 versus K2O; and (c) A/CNK versus A/NK. The dark shaded areas (from dark to light in a and b) indicate the early Carboniferous, early late Carboniferous, and early Permian igneous rocks within the Xing'an Massif, respectively (Li et al., 2013; Liu et al., 2012; Wang et al., 2013; Zhang et al., 2013; Zhao et al., 2010a). The boundary lines in the SiO2 versus (Na2O + K2O), SiO2 versus K2O, and A/CNK versus A/NK diagrams are from Irvine and Baragar (1971), Peccerillo and Taylor (1976), and Maniar and Piccoli (1989), respectively.

margin of the Xing'an Massif provide new insights into the timing of amalgamation between the Xing'an and Songnen–Zhangguangcai Range massifs. First, the early late Carboniferous rhyolites and dacites from the western margin of the Songnen–Zhangguangcai Range Massif are chemically

peraluminous (ACNK = 1.04–1.22) and have affinities to adakitic rocks, as indicated by their low abundances of HREEs and relatively high Sr concentrations. These geochemical signatures imply that the rocks formed in a compressional tectonic regime associated with crustal thickening during a collisional orogenic event (Barbarin, 1999; Harris et al., 1986).

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Fig. 6. Chondrite-normalized rare earth element (REE) patterns (a, c, and e), and primitive-mantle-normalized trace element spidergrams (b, d, and f) for early Carboniferous–early Permian volcanic rocks examined in this study. The meaning of the shaded areas is the same as in Fig. 5. Chondrite and primitive mantle normalizing values are from Boynton (1984) and Sun and McDonough (1989), respectively.

Moreover, on diagrams of FeO T/MgO and K 2 O + Na 2O/CaO versus Zr + Nb + Ce + Y (Fig. 8; Whalen et al., 1987), the early late Carboniferous rhyolites occur mainly in the fields of fractionated felsic granites (FG) and unfractionated M-, I-, and S-type granites (orogenic granite types, OGT). Taken together, we conclude that the early late Carboniferous

rhyolites and dacites on the western margin of the Songnen– Zhangguangcai Range Massif formed in a collisional tectonic setting. Second, the geochemical characteristics of the coeval granitic mylonites, granitic gneisses, and granitoids on the eastern margin of the Xing'an Massif reveal that they formed in a compressional tectonic

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407

Fig. 7. Correlations between Hf isotopic compositions and ages of zircons from the early Carboniferous–early Permian volcanic rocks in the study area. CAOB: Central Asian Orogenic Belt; YFTB: Yanshan Fold and Thrust Belt (Yang et al., 2006).

setting (Cui et al., 2013; Gao et al., 2013; Wang et al., 2013; Zhang et al., 2010). In summary, we conclude that the early late Carboniferous igneous rocks from both sides of the Heihe–Nenjiang suture zone formed in a collisional tectonic setting, implying that collision and amalgamation of the Xing'an and Songnen–Zhangguangcai Range massifs occurred during the early late Carboniferous. This view is also supported by stratigraphic data in the study area: lower Carboniferous and upper Carboniferous strata in the northwestern Lesser Xing'an Range are composed of marine and continental deposits, respectively. In addition, the depositional sequence of the Serpukhovian, Bashkirian, and Moscovian stages is missing in the study area and in adjacent regions ((HBGMR, 1993;) IMBGMR, 1996), indicating that the early late Carboniferous was a period of transformation from marine to continental environments (HBGMR, 1993; IMBGMR, 1996; JBGMR, 1988). Therefore, we consider that the early late Carboniferous magmatic events in the Xing'an and Songnen–Zhangguangcai Range massifs mark the collision and amalgamation of two microcontinental blocks (Fig. 10b).

5.3.3. Early Permian post-orogenic extension The early Permian rhyolites from the western margin of the Songnen–Zhangguangcai Range Massif exhibit chemical affinities to A-type rhyolites (Fig. 8; Whalen et al., 1987) suggesting that they formed in an extensional environment, which is also supported by the occurrence of early Permian bimodal volcanic rocks in the Songnen–Zhangguangcai Range Massif (Meng et al., 2011). Moreover, coeval A-type granites are widely recognized in the Xing'an Massif (Hong et al., 1994; Shi et al., 2004; Sun et al., 2000; Wu et al., 2002, 2011; Zhang et al., 2013). The widespread occurrence of A-type granites as well as rhyolites in both the Xing'an and Songnen–Zhangguangcai Range massifs suggests that the two blocks were in a post-collisional extensional environment during the early Permian (Fig. 10c). In summary, we conclude that the late Paleozoic tectonic evolution of the Xing'an and Songnen–Zhangguangcai Range massifs involved early Carboniferous subduction of the Paleo-Asian oceanic plate beneath the Xing'an Massif, followed by early late Carboniferous collision and amalgamation, and early Permian post-collisional extension.

Fig. 8. Plots of Zr + Nb + Ce + Y versus FeOT/MgO (a) and K2O + Na2O/CaO (b) for early Carboniferous–early Permian volcanic rocks in the study area. The meaning of the shaded area is the same as in Fig. 5. The boundary lines in (a) and (b) are from Whalen et al. (1987). FG: Fractionated felsic granites; OGT: unfractionated M-, I-, and S-type granites; A: A-type granites; FeOT: total FeO.

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Fig. 9. Tectonic discrimination diagrams for granitoids (Pearce et al., 1984). The shaded areas indicate early Carboniferous–early Permian igneous rocks in the Xing'an Massif. ORG: ocean ridge granites; VAG: volcanic arc granites; WPG: within-plate granites; syn-COLG: syn-collision granites.

Fig. 10. Simplified schematic showing a tectonic evolutionary model for the Xing'an and Songnen–Zhangguangcai Range massifs during the early Carboniferous–early Permian. XA: Xing'an Massif; SZM: Songnen–Zhangguangcai Range Massif.

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6. Conclusions The following conclusions are based on zircon U–Pb ages and geochemical data presented in this paper. 1. Late Paleozoic magmatism on the western margin of the Songnen– Zhangguangcai Range Massif can be subdivided into at least three stages: early Carboniferous (~ 351 Ma), early late Carboniferous (~319 Ma), and early Permian (295–293 Ma). 2. Early Carboniferous A-type rhyolites formed in an extensional setting, from a primary magma derived mainly from partial melting of newly accreted continental crust. 3. Early late Carboniferous volcanic rocks formed in a compressional tectonic setting, implying that collision and amalgamation of the Xing'an and Songnen–Zhangguangcai Range massifs took place in the early late Carboniferous. 4. Early Permian A-type rhyolites reveal that the two massifs experienced a post-collisional extensional environment. Supplementary data to this article can be found online at http://dx. doi.org/10.1016/j.lithos.2014.07.008. Acknowledgments We thank the staff of the State Key Laboratory of Geological Processes and Mineral Resources, China University of Geosciences, Wuhan, China, for their advice and assistance during U–Pb zircon dating, major and trace element analyses, and Hf isotope analyses. This work was financially supported by the National Key Basic Research Program of China (2013CB429802), the National Natural Science Foundation of China (Grants 41272077, 41330206), the Ministry of Land and Resources of the People's Republic of China (grant 201311018 and 12120114085401), and by the Opening Foundation of the State Key Laboratory of Geological Processes and Mineral Resources, China University of Geosciences (Wuhan) (GPMR201303). References Amelin, Y., Lee, D.C., Halliday, A.N., 2000. Early–middle Archaean crustal evolution deduced from Lu–Hf and U–Pb isotopic studies of single zircon grains. Geochimica et Cosmochimica Acta 64 (24), 4205–4225. Anderson, T., 2002. Correction of common lead in U–Pb analyses that do not report 204Pb. Chemical Geology 192 (1), 59–79. Barbarin, B., 1999. A review of the relationships between granitoid types, their origins and their geodynamic environments. Lithos 46 (3), 605–626. Blichert-Toft, J., Albarède, F., 1997. The Lu–Hf isotope geochemistry of chondrites and the evolution of the mantle–crust system. Earth and Planetary Science Letters 148 (1), 243–258. Boynton, W.V., 1984. Geochemistry of the rare earth elements: meteorite studies. In: Henderson, P. (Ed.), Rare Earth Element Geochemistry. Elservier, pp. 63–114. Chen, B., Jahn, B.M., Wilde, S., Xu, B., 2000. Two contrasting Paleozoic magmatic belts in northern Inner Mongolia, China: petrogenesis and tectonic implications. Tectonophysics 328 (1), 157–182. Cui, F.H., Zheng, C.Q., Xu, X.C., Yao, W.G., Shi, L., Li, J., Xu, J.L., 2013. Late Carboniferous magmatic activities in the Quanshenglinchang area, Great Xing'an Range: constrains on the timing of amalgamation between Xing'an and Songnen massifs. Acta Geologica Sinica 87 (9), 1247–1263 (in Chinese with English abstract). Eby, G.N., 1992. Chemical subdivision of the A-type granitoids: petrogenetic and tectonic implications. Geology 20 (7), 641–644. Gao, F.,Zheng, C.Q.,Yao, W.G.,Li, J.,Shi, L.,Cui, F.H.,Gao, Y.,Zhang, X.X., 2013. Geochronology and geochemistry characteristics of the granitic mylonitic gneiss in the Zhalantun Haduohe area of the northern Great Xing'an Range. Acta Geologica Sinica 87 (9), 1277–1292 (in Chinese with English abstract). Gill, J.B., 1981. Orogenic Andesites and Plate Tectonics. Springer-Verlag, Berlin. Griffin, W.L.,Pearson, N.J.,Belousova, E.,Jackson, S.E.,Achterbergh, E.,O' Reilly, S.Y.,Shee, S. R., 2000. The Hf isotope composition of cratonic mantle: LAM-MC-ICPMS analysis of zircon megacrysts in kimberlites. Geochimica et Cosmochimica Acta 64 (1), 133–147. Grove, T.L., Elkins-Tanton, L.T., Parman, S.W., Cartterjee, N., Müntener, O., Gaetani, G.A., 2003. Fractional crystallization and mantle-melting controls on calc-alkaline differentiation trends. Contributions to Mineralogy and Petrology 145 (5), 515–533. Harris, N.B.W.,Pearce, J.A.,Tindle, A.G., 1986. Geochemical characteristics of collision–zone magmatism. Geological Society, London, Special Publications 19 (1), 67–81. HBGMR (Heilongjiang Bureau of Geology Mineral Resources), 1987. Report of 1:200,000 Regional Geological Research (Chenqing Sheet, in Chinese). HBGMR (Heilongjiang Bureau of Geology Mineral Resources), 1991. Report of 1:200,000 Regional Geological Research (Sunwu Sheet, in Chinese).

409

HBGMR (Heilongjiang Bureau of Geology Mineral Resources), 1993. Regional Geology of Heilongjiang Province. Geological Publishing House, Beijing (in Chinese with English summary). Hong, D.W.,Huang, H.Z.,Xiao, Y.J.,Xu, H.M., 1994. The Permian alkaline granites in central Inner Mongolia and their geodynamic significance. Acta Geologica Sinica 68 (3), 219–230 (in Chinese with English abstract). Hu, Z.C.,Liu, Y.S.,Gao, S.,Hu, S.H.,Dietiker, R.,Günther, D., 2008a. A local aerosol extraction strategy for the determination of the aerosol composition in laser ablation inductively coupled plasma mass spectrometry. Journal of Analytical Atomic Spectrometry 23 (9), 1192–1203. Hu, Z.C.,Gao, S.,Liu, Y.S.,Hu, S.H.,Chen, H.H.,Yuan, H.L., 2008b. Signal enhancement in laser ablation ICP-MS by addition of nitrogen in the central channel gas. Journal of Analytical Atomic Spectrometry 23 (8), 1093–1101. Hu, Z.C., Liu, Y.S., Gao, S., Liu, W.G., Yang, L., Zhang, W., Tong, X.R., Lin, L., Zong, K.Q., Li, M., Chen, H.H., Zhou, L., 2012. Improved in situ Hf isotope ratio analysis of zircon using newly designed X skimmer cone and jet sample cone in combination with the addition of nitrogen by laser ablation multiple collector ICP–MS. Journal of Analytical Atomic Spectrometry 27 (9), 1391–1399. IMBGMR (Inner Mongolian Bureau of Geology Mineral Resources), 1996. Regional Geology of Inner Mongolia. Geological Publishing House, Beijing (in Chinese with English abstract). Irvine, T.H., Baragar, W.R.A., 1971. A guide to the chemical classification of the common volcanic rocks. Canadian Journal of Earth Sciences 8 (5), 523–548. Jahn, B.M.,Wu, F.Y.,Chen, B., 2000. Massive granitoid generation in Central Asia: Nd isotopic evidence and implication for continental growth in the Phanerozoic. Episodes 23 (2), 82–92. JBGMR (Jilin Bureau of Geology and Mineral Resources), 1988. Regional Geology of Jilin Province. Geological Publishing House, Beijing (in Chinese with English summary). Koschek, G., 1993. Origin and significance of the SEM cathodoluminescence from zircon. Journal of Microscopy 171 (3), 223–232. Li, J.Y., 2006. Permian geodynamic setting of Northeast China and adjacent regions: closure of the Paleo-Asian Ocean and subduction of the Paleo-Pacific Plate. Journal of Asian Earth Sciences 26 (3), 207–224. Li, C.L.,Qu, H.,Zhao, Z.H.,Xu, G.Z.,Wang, Z.,Zhang, J.F., 2013. Zircon U–Pb ages, geochemical characteristics and tectonic implications of early Carboniferous granites in Huolongmen area, Heilongjiang Province. Geology in China 40 (3), 859–868 (in Chinese with English abstract). Liu, Y.S., Hu, Z.C., Gao, S., Günther, D., Xu, J., Gao, C.G., Chen, H.H., 2008. In situ analysis of major and trace elements of anhydrous minerals by LA-ICP-MS without applying an internal standard. Chemical Geology 257 (1), 34–43. Liu, Y.S., Gao, S., Hu, Z.C., Gao, C.G., Zong, K.Q., Wang, D.B., 2010. Continental and oceanic crust recycling-induced melt-peridotite interactions in the Trans-North China Orogen: U–Pb dating, Hf isotopes and trace elements in zircons of mantle xenoliths. Journal of Petrology 51, 537–571. Liu, G., Lv, X.B., Zhang, L., Cao, X.F., Chen, Y., Chen, C., Liu, H., Chen, J., 2012. Geochemical characteristics of early Carboniferous volcanic rocks in Hongyanarea of northwestern Xiao Hinggan Mountains and their geological significance. Acta Petrologica et Mineralogica 31 (5), 641–651 (in Chinese with English abstract). Ludwig, K.R., 2003. Isoplot/Ex, Version 3: a Geochronological Toolkit for Microsoft Excel. Geochronology Centre Berkeley, California. Maniar, P.D., Piccoli, P.M., 1989. Tectonic discrimination of granitoids. Geological Society of America Bulletin 101 (5), 635–643. Meng, E., Xu, W.L.,Pei, F.P.,Yang, D.B., Yu, Y.,Zhang, X.Z., 2010. Detrital-zircon geochronology of Late Paleozoic sedimentary rocks in eastern Heilongjiang Province, NE China: implications for the tectonic evolution of the eastern segment of the Central Asian Orogenic Belt. Tectonophysics 485 (1), 42–51. Meng, E.,Xu, W.L.,Pei, F.P.,Yang, D.B.,Wang, F.,Zhang, X.Z., 2011. Permian bimodal volcanism in the Zhangguangcai Range of eastern Heilongjiang Province, NE China: zircon U–Pb–Hf isotopes and geochemical evidence. Journal of Asian Earth Sciences 41 (2), 119–132. Miao, L.C., Fan, W.M., Zhang, F.Q., Zhang, F.Q., Liu, D.Y., Jian, P., Shi, G.H., Tao, H., Shi, Y.R., 2003. Zircon SHRIMP geochronology of the Xinkailing–Kele complex in the northwestern Lesser Xing'an Range, and its geological implications. Chinese Science Bulletin 48 (22), 2315–2323 (in Chinese with English abstract). Miao, L.C., Liu, D.Y., Zhang, F.Q., Fan, W.M., Shi, Y.R., Xie, H.Q., 2007. Zircon SHRIMP U–Pb ages of the “Xinghuadukou Group” in Hanjiayuanzi and Xinlin areas and the “Zhalantun Group” in Inner Mongolia, Da Hinggan Mountains. Chinese Science Bulletin 52, 1112–1134 (in Chinese with English abstract). Nowell, G.M.,Kempton, P.D.,Noble, S.R.,Fitton, J.G.,Saunders, A.D.,Mahoney, J.J.,Taylor, R.N., 1998. High precision Hf isotope measurements of MORB and OIB by thermal ionisation mass spectrometry: insights into the depleted mantle. Chemical Geology 149 (3), 211–233. Pearce, J.A., Harris, N.B.W., Tindle, A.G., 1984. Trace element doscromination diagrams for the tectonic interpretation of granitic rocks. Journal of Petrology 25 (4), 956–983. Peccerillo, A., Taylor, S.R., 1976. Geochemistry of Eocene calc-alkaline volcanic rocks from the Kastamonu area, Northern Turkey. Contributions to Mineralogy and Petrology 58 (1), 63–81. Pupin, J.P., 1980. Zircon and granite petrology. Contributions to Mineralogy and Petrology 73 (3), 207–220. Rudnick, R.L.,Gao, S., Ling, W.L.,Liu, Y.S., McDonough, W.F., 2004. Petrology and geochemistry of spinel peridotite xenoliths from Hannuoba and Qixia, North China Craton. Lithos 77 (1), 609–637. Sengör, A.M.C., Natal'in, B.A., Burtman, V.S., 1993. Evolution of the Altaid tectonic collage and Paleozoic crustal growth in Eurasia. Nature 364, 299–307. Shi, G.H., Miao, L.C., Zhang, F.Q., Jian, P., Fan, W.M., Liu, D.Y., 2004. The age and its district tectonic implications on Xilinhot A-type granites, Inner Mongolia. Chinese Science Bulletin 49 (7), 723–729 (in Chinese with English abstract).

410

Y. Li et al. / Lithos 205 (2014) 394–410

Sorokin, A.A., Kudryashov, N.M., Li, J.Y., Zhuravlev, D.Z., Pin, Y., Sun, G.H., Gao, L.M., 2004. Early Paleozoic granitoids in the eastern margin of the Arguna' terrane, Amur area: first geochemical and geochronological data. Petrology 12, 367–376. Su, Y.Z., 1996. Paleozoic stratigraphy of Xing'an stratigraphical province. Jilin Geology 15, 23–34 (in Chinese with English abstract). Sun, S.S., McDonough, W.F., 1989. Chemical and isotopic systematics of oceanic basalts: implications for mantle composition and processes. In: Saunders, A.D., Norry, M.J. (Eds.), Magmatism in Ocean Basins. Geological Society of Special Publication, London, pp. 313–345. Sun, D.Y., Wu, F.Y., Li, H.M., Lin, Q., 2000. Emplacement age of the post-orogenic A-type granites in Northwestern Lesser Xing'an Range, and its relationship to the eastward extension of Suolushan–Hegenshan–Zhalaite collisional suture zone. Chinese Science Bulletin 45 (20), 2217–2222 (in Chinese with English abstract). Sylvester, P.J., 1989. Post-collisional alkaline granites. The Journal of Geology 97, 261–280. Tang, K.D., Shao, J.A., Li, Y.F., 2011. Songnen Massif and its research significance. Earth Science Frontiers 18, 57–65 (in Chinese with English abstract). Tang, J., Xu, W.L., Wang, F., Wang, W., Xu, M.J., Zhang, Y.H., 2014. Geochronology and geochemistry of Early–Middle Triassic magmatism in the Erguna Massif, NE China: constraints on the tectonic evolution of the Mongol–Okhotsk Ocean. Lithos 184–187, 1–16. Tong, Y., Hong, D.W., Wang, T., Shi, X.J., Zhang, J.J., Zeng, T., 2010. Spatial and temporal distribution of granitoids in the middle segment of the Sino-Mongolian Border and its tectonic and metallogenic implications. Acta Geoscientica Sinica 31 (3), 395–412 (in Chinese with English abstract). Wang, F.,Xu, W.L.,Meng, E.,Cao, H.H.,Gao, F.H., 2012. Early Paleozoic amalgamation of the Songnen–Zhangguangcai Range and Jiamusi massifs in the eastern segment of the Central Asian Orogenic Belt: geochronological and geochemical evidence from granitoids and rhyolites. Journal of Asian Earth Sciences 49, 234–248. Wang, Y., Yang, X.P., Na, F.C., Zhang, G.Y., Kang, Z., Liu, Y.C., Zhang, W.L., Mao, Z.X., 2013. Determination and geological implication of the granitic mylonite in Nenjiang– Heihe tectonic belt. Geology and Resources 22 (6), 452–459 (in Chinese with English abstract). Wang, F., Xu, W.L., Gao, F.H., Zhang, H.H., Pei, F.P., Zhao, L., Yang, Y., 2014. Precambrian terrane within the Songnen–Zhangguangcai Range Massif, NE China: evidence from U–Pb ages of detrital zircons from the Dongfengshan and Tadong groups. Gondwana Research 26 (1), 402–413. Whalen, J.B.,Currie, K.L.,Chappell, B.W., 1987. A-type granites: geochemical characteristics discrimination and petrogenesis. Contributions to Mineralogy and Petrology 95 (4), 407–419. Wilde, S.A., Wu, F.Y., Zhang, X.Z., 2003. Late Pan-African magmatism in northeastern China: SHRIMP U–Pb zircon evidence from granitoids in the Jiamusi Massif. Precambrian Research 122 (1), 311–327. Wilson, B.M., 1989. Igneous Petrogenesis a Global Tectonic Approach. Springer, London. Windley, B.F., Alexeiev, D., Xiao, W.J., Kröner, A., Badarch, G., 2007. Tectonic models for accretion of the Central Asian Orogenic Belt. Journal of Geological Society 164 (1), 31–47.

Wu, F.Y., Sun, D.Y., Li, H.M., Jahn, B.-M., Wilde, S.A., 2002. A-type granites in northeastern China: age and geochemical constraints on their petrogenesis. Chemical Geology 187 (1), 143–173. Wu, F.Y.,Zhao, G.C.,Sun, D.Y.,Wilde, S.A.,Zhang, J.H., 2007. The Hulan Group: its role in the evolution of the Central Asian Orogenic Belt of NE China. Journal of Asian Earth Sciences 30, 542–556. Wu, F.Y.,Sun, D.Y., Ge, W.C., Zhang, Y.B., Grant, M.L., Wilde, S.A., Jahn, B.M., 2011. Geochronology of the Phanerozoic granitoids in northeastern China. Journal of Asian Earth Sciences 41 (1), 1–30. Xiao, W.J., Zhang, L.C., Qin, K.Z., Sun, S., Li, J.Y., 2004. Paleozoic accretionary and collisional tectonics of the eastern Tianshan (China): implications for the continental growth of central Asia. American Journal of Science 304 (4), 370–395. Xu, W.L.,Sun, D.Y., Ying, X.Y., 1999. Evolution of Hercynian orogenic belt in Daxing'anling Mt: evidence from granitic rocks. Journal of Changchun University of Science and Technology 29 (4), 319–323 (in Chinese with English abstract). Xu, W.L.,Ji, W.Q.,Pei, F.P.,Meng, E.,Yu, Y.,Yang, D.B.,Zhang, X.Z., 2009. Triassic volcanism in eastern Heilongjiang and Jilin Provinces, NE China: chronology, geochemistry, and tectonic implications. Journal of Asian Earth Sciences 34 (3), 392–402. Xu, W.L., Pei, F.P.,Wang, F., Meng, E., Ji, W.Q.,Yang, D.B., Wang, W., 2013. Spatial–temporal relationships of Mesozoic volcanic rocks in NE China: constraints on tectonic overprinting and transformations between multiple tectonic regimes. Journal of Asian Earth Sciences 74, 167–193. Yang, J.H., Wu, F.Y., Shao, J.A., Wilde, S.A., Xie, L.W., Liu, X.M., 2006. Constraints on the timing of uplift of the Yanshan Fold and Thrust Belt, North China. Earth and Planetary Science Letters 246 (3), 336–352. Yuan, H.L., Gao, S., Liu, X.M., Li, H.M., Günther, D., Wu, F.Z., 2004. Accurate U–Pb age and trace element determinations of zircon by laser ablation inductively coupled plasmamass spectrometry. Geostandards and Geoanalytical Research 28 (3), 353–370. Zen, E., 1986. Aluminum enrichment in silicate melts by fractional crystallization: some mineralogic and petrographic constraints. Journal of Petrology 27 (5), 1095–1117. Zhang, Y.L.,Ge, W.C.,Gao, Y.,Chen, J.S., Zhao, L., 2010. Zircon U–Pb ages and Hf isotopes of granites in Longzhen area and their geological implications. Acta Petrologica Sinica 26 (4), 1059–1073 (in Chinese with English abstract). Zhang, C., Liu, Z.H.,Xu, Z.Y.,Li, S.C., Fan, Z.W.,Li, G., 2013. Characteristics and genesis of the Wuyi Forestry Center granite in the Da Hinggan Mountains. Geological Bulletin of China 32 (2/3), 365–373 (in Chinese with English abstract). Zhao, Z.,Chi, X.G., Pan, S.Y.,Liu, J.F., Sun, W.,Hu, Z.C., 2010a. Zircon U-Pb LA-ICP-MS dating of Carboniferous volcanics and its geological significance in the northwestern Lesser Xing'an Range. Acta Petrologica Sinica 26 (8), 2452–2464 (in Chinese with English abstract). Zhao, Z.,Chi, X.G.,Liu, J.F.,Wang, T.F.,Hu, Z.C., 2010b. Late Paleozoic arc-related magmatism in Yakeshi region, Inner Mongolia chronological and geochemical evidence. Acta Petrologica Sinica 26 (11), 3245–3258 (in Chinese with English abstract). Zhu, Y.F.,Sun, S.H.,Gu, L.B.,Ogasawara, Y.,Jiang, N.,Honwa, H., 2001. Permian volcanism in the Mongolian orogenic zone, northeast China: geochemistry, magma sources and petrogenesis. Geological Magazine 138 (02), 101–115.