
Citation: | Tong Li, Liang Liu, Xiao-Ying Liao, Yong-Sheng Gai, Tuo Ma, Chao Wang. Geochemistry, Sr-Nd-Pb Isotopic Compositions and Zircon U-Pb Geochronology of Neoproterozoic Mafic Dyke in the Douling Complex, South Qinling Belt, China. Journal of Earth Science, 2020, 31(2): 237-248. doi: 10.1007/s12583-020-1298-6 |
The mafic dyke swarm is widely developed in the Proterozoic continental lithosphere all over the world and is an important and unique geological structure unit in the ancient craton. Development of mafic dyke indicates the existence of a fairly large scale of consolidated stable rigid landmasses that provides information about the evolution of magmatic source in early deep earth and continental lithosphere and records important geological event of ancient continental break-up, which is a favorable sign of supercontinent reconstruction (Zhou et al., 1998; Li et al., 1997; Windley, 1989; Clifford, 1987).
The Qinling orogenic belt (QOB) is a complex orogenic belt formed by the collision of the North China Block (NCB) and the Yangtze Block (YZB) that has experienced different tectonic stages (Zhang, 2001). As an important link between the YZB and the North Qinling belt (NQB), the South Qinling belt (SQB) is generally considered to be developed from the YZB (Zhang, 2001). Douling complex, the oldest crystalline basement of SQB, is mainly composed of biotite gneisses, amphibolites, subordinate schists, marbles and leptynites (G et al., 2004, 1996; Shen et al., 1997; Zhao et al., 1995). In which, the protolith age of the gneisses was interpreted as Neoarchean to Neoproterozoic (Nie et al., 2016; Hu et al., 2013; Lu et al., 2009; G et al., 2004, 1996; Ratschbacher et al., 2003; Zhang Z Q et al., 2002; Shen et al., 1997; Gao et al., 1996; Zhang H F et al., 1996). It was fragmented by voluminous Mid-Neoproterozoic diorite, granodiorite and granite (Bai et al., 2019; Zhang J et al., 2018; Nie et al., 2016; Yang et al., 2011; Zhang C L et al., 2004). The previous studies on Douling complex have mainly focused on the protolith age (Nie et al., 2016; Wu et al., 2014; Hu et al., 2013; Zhang S G et al., 2004, 1996; Ratschbacher et al., 2003; Zhang Z Q, 2002; Shen et al., 1997; Gao et al., 1996; Zhang H F et al., 1996), tectonic attribution (Yang et al., 2011; Hao et al., 1996; Zhang S G et al., 1996; Zhao et al., 1995; Yuan et al., 1994), metamorphism age (Hu et al., 2019, 2013; Zhang S G et al., 2004; Shen et al., 1997) and the Neoproterozoic magmatism (Bai et al., 2019; Nie et al., 2019, 2016; Zhang J et al., 2018; Yang et al., 2011; Zhang C L et al., 2004), whereas research on the Neoproterozoic mafic dyke intruded in the Douling complex is relatively weak (Zhang, 2001), which limits the further understanding of tectonic setting of the SQB in Neoproterozoic. In addition, the mafic dyke swarms are widely distributed in the Wudang Block and Yaolinghe Group of the SQB in Neoproterozoic (Shi et al., 2013; Ling et al., 2010, 2008, 2002a, b; Xia et al., 2008; Su et al., 2006), but the genetic and tectonic relations between them and Douling complex have not been thoroughly investigated. Therefore, research on mafic dyke in the Douling complex of SQB can help us to better understand the tectonic evolution history of the SQB and the QOB in Neoproterozoic.
Based on the field investigation, we have identified the mafic yke formed at ca. 731 Ma that intruded into the plagioclase-amphibole gneiss of Douling complex in Gangou, Xixia area. In this paper, we carried out petrology, geochemistry, Sr-Nd-Pb isotope and geochronology of the mafic dyke, to determine the formation age, magma source and petrogenesis, and to provide further constraints on the Neoproterozoic evolution of the SQB.
The QOB is considered to be a complex orogenic belt that located in central China (Dong and Santosh, 2016; Liu et al., 2016; Dong et al., 2015, 2014, 2011a, b, c, d; Ratschbacher et al., 2006, 2003; Meng and Zhang, 1999; Zhang G W et al., 1996, 1989; Kr ner et al., 1993; Hsü et al., 1987; Zhang G W, 1987; Mattauer et al., 1985; Zhang Y R, 1985), which is connected with the Dabie metamorphic belt in the east and the Qilian orogen in the west (Fig. 1). As an important link between the NCB and the YZB, the QOB provides a key to understand the collision process of these blocks (Zhang, 2001; Meng and Zhang, 2000, 1999). From north to south, the QOB can be divided into four tectonic units: the southern margin of the NCB, the NQB, the SQB and the northern margin of the YZB (Fig. 1). These belts are separated by the Luonan-Luanchuan fault, Shangnan-Danfeng suture and the Mianxian-Lueyang suture, respectively (Fig. 1; Dong and Santosh, 2016; Dong et al., 2015, 2011a, c; Zhang, 2001; Zhang G W et al., 1996; Zhang Z R et al., 1995). The SQB is mainly composed of Precambrian crystalline basement, transitional basement and Neoproterozoic–Mesozoic sedimentary cover. The Douling metamorphic complex represents the crystalline basement. The Wudang and Yaolinghe groups with low-grade metamorphic volcano-sedimentary represents the transitional basement (Meng and Zhang, 2000; Zhang G W et al., 1995).
The Douling complex (previously named as Douling Group) as a huge lenticle, is distributed intermittently in Xichuan-Xixia County, western Henan Province. It outcrops to the south of Shangdan fault zone along the NWW-SEE direction, with an exposure area about 450 km2 (Fig. 2; Zhang, 2002). It mainly consists of biotite gneisses, amphibolites and subordinate hornblende gneisses, calciosilicate leptynites, graphite schists, and marbles (Dong and Santosh, 2016; Liu et al., 2016; Zhang C L et al., 2004; Zhang Z Q et al., 2004; Zhao et al., 1995) that experienced amphibolite-facies metamorphism and overprinted greenschist-facies metamorphism (Hu, et al., 2019; Zhang S G et al., 2004, 1996). Some research suggests that the protolith of the Douling complex mainly formed from the Paleoproterozoic to Neoproterozoic (Lu et al., 2009; Zhang S G et al., 2004, 1996; Ratschbacher et al., 2003; Zhang Z Q, 2002; Shen et al., 1997; Gao et al., 1996; Zhang H F et al., 1996). However, new zircons U-Pb dating yieled protolith ages of ca. 2.5 Ga for gneisses in the Douling complex (Nie et al., 2016; Hu et al., 2013; Zhang S G et al., 2004), with a metamorphic record of 820–815 Ma (Hu et al., 2019, 2013; Shen et al., 1997). In addition, Neoproterozoic dioritic and granitic intrusions of ca. 759–685 Ma were widely developed in the Douling complex (Bai et al., 2019; Zhang J et al., 2018; Shi et al., 2013; Chen et al., 2006; Zhang C L et al., 2004; Li et al., 2003; Lu et al., 1999; Zhang S G et al., 1996). There are also some mafic-ultramafic rocks developed in the Douling complex. However, the properties and tectonic significance are still unclear (Zhang, 2001).
The Wudang and Yaolinghe groups are regarded as the most important parts of the transitional basement in SQB, which composed of greenschist facies metamorphism volcano-sedimentary sequences (Fig. 1; Zhang, 2001). The Wudang Group is mainly exposed in northwest Hubei Province, and the Yaolinghe Group is distributed around Wudang dome (Zhu et al., 2009; Ling et al., 2002a). The Wudang Group is composed of metamorphic sedimentary rocks of Yangping Formation and metamorphic volcano-sedimentary rocks of Shuangtai Formation formed at ca. 755 Ma. The Yaolinghe Group consists of basaltic lava and felsic volcano-sedimentary rock with the age of ca. 685 Ma (Ling et al., 2008). As for the formation of Wudang Group, some research suggests that the Wudang Group was formed in the continental marginal arc setting (Su et al., 2006; Ling et al., 2002a, b), and others suggest that it was formed in the intracontinental rift setting (Ling et al., 2010; Xia et al., 2008). However, the igneous rocks from the Yaolinghe Group are often considered as the products of intracontinental rift (Shi et al., 2013; Ling et al., 2010, 2008, 2002a, b).
Diabase samples were collected from the Douling complex in Gangou (33°12'27.2" N, 111°30'15.6" E), southeast of Xixia area (Fig. 2). The diabase dyke exposed with a width of 4–5 m which intruded into the plagioclase-amphibole gneiss of Douling Group (Fig. 3a). The rocks are grayish green with dense massive structure, fine grain and ophitic texture, which has been subjected to a certain degree of weathering alteration (Fig. 4). Felsic veinlets of 1–5 mm that intruded late can be seen on the outcrop and hand specimen (Fig. 3b). The diabase consists of plagioclase (~50%), clinopyroxene (~45%) and minor biotite (< 5%). The accessory minerals are mainly titanite, magnetite, zircon and apatite. Plagioclases are generally subhedral, and range from 0.2 to 0.5 mm with polycrystalline twins, which has been partly altered to sericite and epidote. Clinopyroxenes are subhedral crystals with grain size about 0.2 mm and commonly distributed between plagioclase septum. The margin of some clinopyroxenes are replaced by amphiboles (Fig. 4).
The analytical methods used in this study include whole rock major and trace element analyses, Sr-Nd-Pb isotope analyses, major mineral elements analyses, zircon cathodeluminescence (CL) imaging and zircon U-Pb dating. The Sr-Nd-Pb isotope analyses were completed in Nanjing FocuMS Technology Co. Ltd. and other analyses were completed in the State Laboratory of Continental Dynamics, Northwest University, China.
Whole rock geochemical samples were coarsely crushed and then finely grounded to less than 200 mesh. Analysis of major and trace element compositions were performed using X-ray fluorescence (XRF) (Rigku RIX 2100) and inductively coupled plasma mass spectrometry (ICP-MS) (PE 6100 DRC), respectively. XRF method was used for major element analysis. Trace elements were analyzed by ICP-MS. The analytical precision and accuracy of major and trace elements are generally better than 5% and 10%, respectively. In addition, one sample from every five samples was randomly selected for analyzing twice to check the precision of the analyses.
The Sr-Nd-Pb isotope pretreatment and mass spectrometry were completed in Nanjing FocuMS Technology Co. Ltd. Sr, total REE and Pb were separated by cationic-strontium resin after high pressure digestion. Nd was separated from the total REE components by Ln resin. The content of Sr, Nd and Pb of the samples were determined on Agilent 7700x quadrupole ICP-MS, and the isotope ratio of the samples were determined on Nu Plasma II MC-ICP-MS. 86Sr/88Sr=0.119 4, 146Nd/144Nd=0.721 9 and 205Tl/203Tl=2.388 5 were used for the determination of isotope ratios of samples Sr, Nd and Pb, respectively, to calibrate mass fractionation. NIST SRM 987, JNdi-1 and NIST SRM 981 were used as external standards to correct instrument drift.
Mineral compositions were determined using a JXA-8230 electron microprobe. Quantitative analyses were performed using a specimen current of 1×10-8 A, an accelerating voltage of 15 kV, with a beam diameter of 1 μm. The analytical precision is generally better than 2%. Mineral standard samples provided by SPI company, different mineral samples are used to calibrate different elements, for example, quartz/jadeite-Si, jadeite/plagioclase-Al, jadeite/albite-Na, diopside-Ca, olivine-Mg, diopside-K, ilmenite-Fe, rhodonite-Mn, rutile-Ti.
Euhedral zircons without inclusions and cracks were separated under binocular microscope, and then fixed on epoxy to be polished to the two-thirds exposed. The internal texture of zircons were obtained using CL imaging. The zircon U-Pb dating was performed on a Agilent 7500a type laser ablation inductively coupled plasma mass spectrometer (LA-ICP-MS). Standard zircon 91500 was used for isotope ratio fractionation correction as the external standard, which was analyzed every five sample points. Element concentration was calculated by using NIST610 as external standard and 29Si as internal standard. U-Th-Pb data of zircons was calculated using GLITTER (ver4.0). The concordia plots and were calculated using ISOPLOT (ver3.0) (Ludwig, 2003). Compositions of the common Pb were corrected according to Andersen Tom's (2002) 3D coordinate method, as shown in the references (Yuan et al., 2008).
The whole rock major and trace element compositions of the Gangou diabase in Xixia area are shown in Table S1.
Samples have 49.02 wt.%–49.37 wt.% SiO2, 3.15 wt.%–3.56 wt.% TiO2, 11.87 wt.%–12.36 wt.% Al2O3, 2.52 wt.%–2.81 wt.% Na2O, 0.26 wt.%–1.02 wt.% K2O and 2.99 wt.%–3.56 wt.% total alkalis (Na2O+K2O), with the ratios of Na2O/K2O > 1. All samples exhibit a tholeiitic trend in the FAM diagram (Fig. 5a). Considering that Na and K are active elements that are susceptible to alteration, Zr/TiO2-Nb/Y diagram (Fig. 5b) is adopted for classification. All samples plot into the area of sub-alkaline basalt. Therefore, the Gangou diabase has the evolution trend of subalkaline tholeiite basalt series.
The total amount of rare earth element (ΣREE) of Gangou diabase in Xixia area is relatively high (155.5×10-6–184.7×10-6), with an average value of 171.0×10-6, which enriched in LREE relative to HREE (ΣLREE/ΣHREE=1.55–1.57) with a weak fractionation between LREE and HREE ((La/Yb)N=3.66–3.90). On the diagram of chondrite-normalized REE patterns (Fig. 6a), it shows a gentle right-dipping curve with less negative Eu anomaly (δEu=0.88–0.93), which reflect a slight fractional crystallization of plagioclase in the magmatic source. Above all, the Gangou diabase has a slightly enriched REE type with the characteristics of high REE a
MORB-normalized trace element spider diagram (Fig. 6b) shows "humped" pattern. The first half of the curve shows enrichment of incompatible elements, while the second half is relatively flat. There is obvious negative Sr anomaly, weak depleted of Nb and Ta, and the differentiation degree of HFSE is also weak. Sr and Eu are preferred to be selectively concentrated in plagioclase, which further indicates the Gangou diabase experienced the fractional crystallization of plagioclase. Consequently, they are geochemically characterized by the transition between ocean island basalt and continental tholeiite. In addition, the Th/Ta (2.02–2.44) and Ta/Hf ratio (0.185–0.200) are also consistent with the continental within-plate setting (Th/Ta > 1.6, Ta/Hf < 0.1), and different from the oceanic witinin-plate setting (Th/Ta < 1.6, Ta/Hf > 0.1) (Wang et al., 2001). In general, the trace element geochemical characteristics of the samples are more similar to those of continental tholeiite.
Compositions of clinopyroxene from the Gangou diabase in Xixia area were analyzed by electron probe with the results shown in Table S2. The content of MgO, CaO, FeO, Al2O3, TiO2 in the 16 clinopyroxenes tested are 12.33 wt.%–15.20 wt.%, 15.18 wt.%–18.91 wt.%, 11.46 wt.%–15.16 wt.%, 1.91 wt.%–3.56 wt.%, 0.78 wt.%–1.42 wt.%, respectively.
Whole-rock Sr-Nd isotopic data for the Gangou diabase are presented in Table S3. The Pb isotopic data are presented in Table S4. The Nd isotope ratio is relatively constant (εNd(t)=2.4–3.5), nevertheless, the ratio of Sr isotope changes greatly ((87Sr/86Sr)i=0.703 5–0.706 5). It can be seen from Table S4 that the Ganou diabase has low Pb isotopic composition with the (206Pb/204Pb)i values ranging from 17.99 to 18.12, (207Pb/204Pb)i values from 15.52 to 15.54 and (208Pb/204Pb)i values from 38.34 to 38.64.
The typical zircon CL images of the Gangou diabase presented in Fig. 7. Most of them are subhedral-euhedral columnar, with a particle size of 60–120 μm and length-width ratio from 1 : 1–2 : 1. The images show wide and uniform magmatic oscillatory zoning, which consistent with the characteristics of zircons in mafic rocks (Koschek, 1993), while a few zircons have obvious magmatic oscillatory zoning. Moreover, zircons with residual core can be also found in this study.
Results for U-Pb single zircon dating of the 24 analyses are presented in Table S5 and Fig. 8. 207Pb/206Pb age was used for older zircons (> 1 000 Ma), while the younger zircons (< 1 000 Ma) used 206Pb/238U age. The results show that the ages of most zircons range from 725–736 Ma with a 206Pb/238U weighted average age of 731±12 Ma (n=9, MSWD=0.032) (Fig. 8), representing the formation age of Gangou diabase. Furthermore, two zircons whose ages range from 105 to 110 Ma are speculated to be the intrusive age of felsic veins in Gangou diabase, which is consistent with the regional research results (Xue, 2018; Hu et al., 2012). Zircons with residual core are of relatively scattered ages (837 to 1 911 Ma, Fig. 8) and speculated that were captured.
Partial melting and fractional crystallization are two main mechanisms of magmatism and evolution. The concentration ratio of hypermagmatophilic elements (such as Ta, Th, La, Ce and so on) and magmophilic elements (such as HREE, Zr, Hf etc.) to hypermagmatophilic elements can distinguish fractional crystallization from partial melting. In the La-La/Sm and La-La/Zr discriminant diagrams (Fig. 9), the horizontal linear distribution of samples indicates fractional crystallization, and the oblique distribution of samples indicates partial melting. All the samples of Gangou diabase were distributed horizontally, indicating that the influence of fractional crystallization. The Gangou diabase have low SiO2 content (49.02 wt.%–49.37 wt.%), Mg#=34.0–37.7 and Ni=31.7×10-6–44.1×10-6. All of them are lower than the value of primary magma (Mg# > 65, Ni > 235×10-6) (Deng, 2004; Hess, 1992; Ringwood, 1975), also implying that the Gangou diabase underwent fractional fractionation from primary magma with mantle source.
Contamination and fractional crystallization usually are very common within the continental setting during the invasion of mantle-derived magma (Yan et al., 2019; Spera and Bohrson, 2004; Thorpe et al., 1984). Rocks contaminated by crustal materials or subduction fluids are characterized by significant depleted of Nb, Ta and Ti (Xiong et al., 2020; Ernst, 2014; Rudnick and Gao, 2003; Frey et al., 2002). In the spider diagram of trace elements (Fig. 6b), the samples show weak negative Nb and Ta anomalies, implying that they were weakly contaminated by crustal materials. Nb/La ratio and (Th/Nb)PM ratio can indicate whether crustal material was added during magma evolution (Xia, 2014; Kieffer et al., 2004; Saunders et al., 1992). Very high (Th/Nb)PM ratios (> > 1) and low Nb/La (< 1) are generally considered reliable trace element indicators for crustal contamination. As shown in Fig. 10a, the Gangou diabase from the Xixia area are characterized by Nb/La=0.79–0.87 and (Th/Nb)N=1.10–1.28, reflecting that they are subject to very weak crustal contamination. The Gangou diabase from Xixia area has similar trace element characteristics with mafic dykes in the Wudang Block (7 samples, according to Ling et al., 2002a; Zhang et al., 1999a) and mafic volcanic rocks of the Yaolinghe Group (6 samples, according to Ling et al., 2002a). (Th/Nb)PM-(La/Nb)PM diagram (Fig. 10b) can distinguish whether the contaminated material comes from the upper crust or the lower crust (Frey et al., 2002; Fitton et al., 1998a, b). The upper crust is rich in La and Th elements, while the lower crust is relatively depleted in Th (Bader et al., 2013). In Fig. 10b, the Gangou diabase fall between the oceanic basalt and the lower crust, which indicates that may be weakly contaminated by lower crust materials during the formation process.
The Gangou diabase has variable initial 87Sr/86Sr ratios (0.703 5–0.706 5) and positive εNd values (2.4–3.5). In Fig. 11, most of samples fall in or near OIB area within the continental lithospheric mantle. In addition, εNd values showed a tendency of migration to the continental lithospheric mantle with the increase of (87Sr/86Sr)i (Fig. 11). The Sr-Nd characteristics of Gangou diabase are similar to that of mafic dykes in the Wudang Block and mafic volcanic rocks of the Yaolinghe Group. Therefore, the primary magma of Gangou diabase should come from an asthenospheric mantle source and influenced by lithospheric composition. The Gangou diabase samples have lower Pb isotopic compositions, and relatively concentrated in the left of the zero geochron line (Fig. 12a) that fall in the area between the DUPAL anomalous oceanic island basalt and the lower crustal trend above the northern hemisphere reference line (NHRL) (Fig. 12b). The ∆208Pb/204Pb values ranged from 96.3 to 119.5, and ∆207Pb/204Pb values varied from 7.13 to 10.28 (Table S3) that similar to the mafic dykes in the Wudang Block and roughly equivalent to the deviation of southern DUPAL anomaly province (Hart, 1984), suggesting that their magma source is similar to the southern DUPAL anomaly ocean island basalt source. Moreover, the correlation diagram of ∆208Pb/204Pb-∆207Pb/204Pb (Fig. 12c) shows that these samples are mainly distributed along the trend of DMM and EMI, indicating an anomaly mantle source that originated from depleted asthenospheric mantle mixed with EMI, which is consistent with the magma source region reflected by Sr-Nd isotope characteristics.
In conclusion, the Gangou diabase in Xixia area originated from partial melting of asthenospheric spinel mantle peridotite with slightly contaminated by the lower crust.
Since the fractional crystallization has little effect on Tb/Yb, it can be used to determine the depth of mantle magma source, i.e., garnet phase (TbN/YbN > 1.8) or spinel phase (TbN/YbN < 1.8) (Wang et al., 2002). The weakly HREE fractionation, no negative anomaly of Y and Yb, and the lower ratio of (La/Yb)N (3.66–3.90) and TbN/YbN (1.50–1.60) suggests that primary magma of the Gangou samples were originated from spinel mantle peridotite. In La/Sm-Sm/Yb (Wilson, 1989) and Nb/Yb-Dy/Yb (Workman and Hart, 2005) diagrams (Figs. 13a, 13b), the Gangou diabase also originated from the partial melting of the spinel mantle peridotite.
The MORB-normalized diagram and ratios of Th/Ta and Ta/Hf show that the characteristics of trace elements are more similar to the geochemical characteristics of continental tholeiite. However, there are some limitations in distinguishing tectonic setting of mafic intrusive rocks by trace elements due to the influence of fractional crystallization (Wang et al., 2016; Xia et al., 2008; Li, 1992). During fractionation crystallization of melt, the way of metal ions entering the lattice of clinopyroxene is different due to different tectonic settings, which results in the obvious difference and differentiation of elements content. The ratio of percentage of tetrahedral sites occupied by Al (IVAl) to clinopyroxene octahedral sites occupied by Ti (IVAl/Ti) of cumulates in the island-arc setting is higher than that in the extensional setting. Thus, compositions of clinopyroxene can be used to identify different tectonic settings (Loucks, 1990). TiO2-IVAl% diagram (Fig. 14) can be obtained after the treatment of the EPMA results of clinopyroxene, which reflects that the IVAl/TiO2 ratios of clinopyroxene in these samples are similar to that of clinopyroxene formed at continental within-plate/rift tectonic setting. Therefore, the Gangou diabase dyke in Xixia area belongs to a continental within-plate rift setting, which is consistent with the recent research on the voluminous dioritic, granodioritic and granitic magma in Neoproterozoic that intruded into Douling complex (Bai et al., 2019; Zhang J et al., 2018; Nie et al., 2016; Yang et al., 2011; Zhang C L et al., 2004a).
The extensive development of mafic dykes indicates the existence of rigid or semi-rigid continental block with a considerable scale and stable consolidation, which is also an important sign of continental block break-up (Windley, 1989). The ca. 731 Ma Gangou dyke that intruded into the amphibole plagiogneiss of the Douling complex, has the similar geochemical and isotopic characteristics of mafic dykes from the ca. 782–755 Ma in the Wudang Block and ca. 796–685 Ma mafic volcanic rocks in the Yaolinghe Group (Ling et al., 2007, 2002a, b; Zhang, 2002; Zhou et al., 1998). These features show that the Douling complex, Wudang Block and Yaolinghe Group have formed in a unified solidified basement (at least before 731 Ma) and the SQB developed strong lithospheric extension or rifting during 796–685 Ma. The Neoproterozoic igneous rocks, which are widely istributed in the northern margin of the YZB and the SQB, are considered to be in response to the event of assembly and breakup of the Rodinia supercontinent (Bai et al., 2019; Nie et al., 2019; Wang et al., 2019; Zhang et al., 2018). The strong lithospheric extension or rifting setting indicated by the Gangou diabase is consistent in time and space with the results of regional studies. Therefore, we speculate that they may have experienced the breaking-up of the Rodinia supercontinent together and then developed into the Qinling Ocean Basin setting in Early Paleozoic.
(1) Zircon LA-ICP-MS U-Pb dating reveal that the Gangou diabase dyke in Xixia area was formed at 731 Ma.
(2) Whole rock major and trace elements characteristics, Sr-Nd-Pb isotopic composition and composition of clinopyroxene indicate that the Gangou diabase dyke was originated from the partial melting of a heterogeneous spinel-bearing mantle source mixed by a slight-depleted asthenospheric mantle and an EMI component in a extensional setting of within-plate rifts.
(3) There are similarities of formation age, petrogenesis, source characteristic and tectonic setting between the Gangou diabase, mafic dykes in the Wudang Block and mafic volcanic rocks in the Yaolinghe Group indicate that the SQB developed strong lithospheric extension or rifting during 796–685 Ma. The solidified basement of SQB may have experienced the breaking-up of the Rodinia supercontinent and then developed into the Qinling ocean basin setting in Early Paleozoic.
We are grateful to three anonymous reviewers for their constructive comments and suggestions. This study was financially supported by the National Nature Science Foundation of China (Nos. 41572049, 41902050, 41430209, 41421002), the Major State Basic Research Development Projects (No. 2015CB856103) and the State Key Laboratory of Continental Dynamics, Northwest University. The final publication is available at Springer via https://doi.org/10.1007/s12583-020-1298-6.
Electronic Supplementary Materials: Supplementary materials (Table S1, S2, S3, S4, S5) are available in the online version of this article at https://doi.org/10.1007/s12583-020-1298-6.
Andersen T.. 2002. Correction of Common Lead in U-Pb Analyses That do not Report 204Pb. Chemical Geology, 192(1/2):59-79. https://doi.org/10.1016/s0009-2541(02)00195-x |
Bader T., Ratschbacher L., Franz L., et al. 2013. The Heart of China Revisited I. Proterozoic Tectonics of the Qin Mountains in the Core of Supercontinent Rodinia. Tectonics, 32(3):661-687. https://doi.org/10.1002/tect.20024 |
Bai Z. A., Shi Y., Liu X. J., et al. 2019. Geochronology, Geochemistry and Hf Isotopes of Fengzishan Pluton in South Qinling and Its Geological Significance. Earth Science, 44(4):1187-1201 (in Chinese with English Abstract). https://doi.org/10.3799/dqkx.2018.586 |
Boynton W. V.. 1984. Cosmochemistry of the Rare Earth Elements: Meteorite, Studies. In: Henderson P., ed., Rare Earth Element Geochemistry. Elsevier, Amsterdam. 63-114. https: //doi.org/10.1016/b978-0-444-42148-7.50008-3 |
Chen Z. H., Lu S. N., Li H. K., et al. 2006. Constraining the Role of the Qinling Orogen in the Assembly and Break-up of Rodinia:Tectonic Implications for Neoproterozoic Granite Occurrences. Journal of Asian Earth Sciences, 28(1):99-115. https://doi.org/10.1016/j.jseaes.2005.03.011 |
Clifford P. M.. 1987. Mafic Dyke Swarms. In:Halls H. C., Fahrig W. F., eds., Geological Association of Canada, Special Paper 34, 52(10):2552. https://doi.org/10.1016/0016-7037(88)90317-1 |
Deng J. F.. 2004. Petrogenesis, Tectonic Environment and Mineralization. In: Luo Z. H., Su S. G., Mo X. X., et al. eds., Geology Press, Beijing (in Chinese) |
Dong Y. P., Genser J., Neubauer F., et al. 2011a. U-Pb and 40Ar/39Ar Geochronological Constraints on the Exhumation History of the North Qinling Terrane, China. Gondwana Research, 19(4):881-893. https://doi.org/10.1016/j.gr.2010.09.007 |
Dong Y. P., Liu X. M., Santosh M., et al. 2011b. Neoproterozoic Subduction Tectonics of the Northwestern Yangtze Block in South China:Constrains from Zircon U-Pb Geochronology and Geochemistry of Mafic Intrusions in the Hannan Massif. Precambrian Research, 189(1/2):66-90. https://doi.org/10.1016/j.precamres.2011.05.002 |
Dong Y. P., Santosh M.. 2016. Tectonic Architecture and Multiple Orogeny of the Qinling Orogenic Belt, Central China. Gondwana Research, 29(1):1-40. https://doi.org/10.1016/j.gr.2015.06.009 |
Dong Y. P., Zhang G. W., Hauzenberger C., et al. 2011c. Palaeozoic Tectonics and Evolutionary History of the Qinling Orogen:Evidence from Geochemistry and Geochronology of Ophiolite and Related Volcanic Rocks. Lithos, 122(1/2):39-56. https://doi.org/10.1016/j.lithos.2010.11.011 |
Dong Y. P., Yang Z., Liu X. M., et al. 2014. Neoproterozoic Amalgamation of the Northern Qinling Terrain to the North China Craton:Constraints from Geochronology and Geochemistry of the Kuanping Ophiolite. Precambrian Research, 255(1):77-95. https://doi.org/10.1016/j.precamres.2014.09.008 |
Dong Y. P., Zhang G. W., Neubauer F., et al. 2011d. Tectonic Evolution of the Qinling Orogen, China:Review and Synthesis. Journal of Asian Earth Sciences, 41(3):213-237. https://doi.org/10.1016/j.jseaes.2011.03.002 |
Dong Y. P., Zhang X. N., Liu X. M., et al. 2015. Propagation Tectonics and Multiple Accretionary Processes of the Qinling Orogen. Journal of Asian Earth Sciences, 104:84-98. https://doi.org/10.1016/j.jseaes.2014.10.007 |
Ernst R. E.. 2014. Large Igneous Provinces. Cambridge University Press, Cambridge. 1-653. https: //doi.org/10.1016/j.gr.2015.07.002 |
Fitton J. G., Hardarson B. S., Ellam R. M., et al. 1998a. Sr-, Nd-, and Pb-Isotopic Composition of Volcanic Rocks from the Southeast Greenland Margin at 63°N:Temporal Variation in Crustal Contamination during Continental Breakup. Proceedings of the Ocean Drilling Program:Scientific Results, 152:351-357. https://doi.org/10.2973/odp.proc.sr.152.251.1998 |
Fitton J. G., Saunders A. D., Larsen L. M., et al. 1998b. Volcanic Rocks from the Southeast Greenland Margin at 63°N:Composition, Petrogenesis, and Mantle Sources. Proceedings of the Ocean Drilling Program:Scientific Results, 152:331-350. https://doi.org/10.2973/odp.proc.sr.152.233.1998 |
Frey F. A.. 2002. Involvement of Continental Crust in the Formation of the Cretaceous Kerguelen Plateau:New Perspectives from ODP Leg 120 Sites. Journal of Petrology, 43(7):1207-1239. https://doi.org/10.1093/petrology/43.7.1207 |
Gao S.. 1996. Geochemical Evidence for the Proterozoic Tectonic Evolution of the Qinling Orogenic Belt and Its Adjacent Margins of the North China and Yangtze Cratons. Precambrian Research, 80(1/2):23-48. https://doi.org/10.1016/0301-9268(95)00100-x |
Hao J., Li Y. J., Liu X. H., et al. 1996. The Douling Paleo-Island Arc and Wudang Paleo-Backarc Basin in East Qinling and Their Geological Significance. Regional Geology of China, 1:44-50 (in Chinese with English Abstract) |
Hart S. R.. 1984. A Large-Scale Isotope Anomaly in the Southern Hemisphere Mantle. Nature, 309(5971):753-757. https://doi.org/10.1038/309753a0 |
Hart S. R.. 1988. Heterogeneous Mantle Domains:Signatures, Genesis and Mixing Chronologies. Earth and Planetary Science Letters, 90(3):273-296. https://doi.org/10.1016/0012-821x(88)90131-8 |
Hess P. C.. 1992. Phase Equilibria Constraints on the Origin of Ocean Floor Basalts. In:Morgan J. P., Blackman D. K., Sinton J. M., eds., Mantle Flow and Melt Generation at Mid-Ocean Ridges. Geophysical Monograph Series, 71:67-102. https://doi.org/10.1029/gm071p0067 |
Hsü K. J., Wang Q. C., Li J. L., et al. 1987. Tectonic Evolution of Qinling Mountains, China. Eclogae Geologicae Helvetiae, 80:735-752 |
Hu J., Liu X. C., Chen L. Y., et al. 2013. A ~2.5 Ga Magmatic Event at the Northern Margin of the Yangtze Craton:Evidence from U-Pb Dating and Hf Isotope Analysis of Zircons from the Douling Complex in the South Qinling Orogen. Chinese Science Bulletin, 58(28/29):3564-3579. https://doi.org/10.1007/s11434-013-5904-1 |
Hu J., Liu X. C., Qu W., et al. 2019. Mid-Neoproterozoic Amphibolite Facies Metamorphism at the Northern Margin of the Yangtze Craton. Precambrian Research, 326:333-343. https://doi.org/10.1016/j.precamres.2017.10.010 |
Hu X. J., Guo A. L., Zong C. L., et al. 2012. 40Ar/39Ar Isotopic Dating, Geochemistry and Their Tectonic Implications of Duofutun Na-Rich Mafic Volcanic Rocks, the Northeastern Margin of the Qinghai-Tibet Plateau. Journal of Northwest University (Natural Science Edition), 42(3):443-452 (in Chinese with English Abstract) |
Huang X., Wu R. L.. 1990. Nd-Sr Isotopes of Granitoids from Shaanxi Province and Their Significance for Tectonic Evolution. Acta Petrologica Sinica, 2:1-11 (in Chinese with English Abstract) |
Irvine T. N., 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. https://doi.org/10.1139/e71-055 |
Kieffer B., Arndt N., Lapierre H., et al. 2004. Flood and Shield Basalts from Ethiopia:Magmas from the African Superswell. Journal of Petrology, 45(4):793-834. https://doi.org/10.1093/petrology/egg112 |
Koschek G.. 1993. Origin and Significance of the SEM Cathodoluminescence from Zircon. Journal of Microscopy, 171(3):223-232. https://doi.org/10.1111/j.1365-2818.1993.tb03379.x |
Krö ner A., Zhang G. W., Sun Y.. 1993. Granulites in the Tongbai Area, Qinling Belt, China:Geochemistry, Petrology, Single Zircon Geochronology, and Implications for the Tectonic Evolution of Eastern Asia. Tectonics, 12(1):245-255. https://doi.org/10.1029/92tc01788 |
Li C. N.. 1992. Trace Element Petrology of Igneous Rocks. China University of Geosciences Press, Wuhan. 1-195 (in Chinese) |
Li H. K., Lu S. N., Chen Z. H., et al. 2003. Zircon U-Pb Geochronology of Rift-Type Volcanic Rocks of the Yaolinghe Group in the South Qinling Orogeny. Geological Bulletin of China, 22(10):775-781 (in Chinese with English Abstract) |
Li J. H., He W. Y., Qian X. L.. 1997. Genetic Mechanism and Tetonic Setting of Proterozoic Mafic Dyke Swarm:Its Implication for Paleoplate Reconstruction. Geological Journal of Chian Universities, 3(3):272-281 (in Chinese with English Abstract) |
Ling W. L., Cheng J. P., Wang X. H., et al. 2002a. Geochemical Features of the Neoproterozoic Igneous Rocks from the Wudang Region and Their Implications for the Reconstruction of the Jinning Tectonic Evolution along the South Qinling Orogenic Belt. Acta Petrologica Sinica, 18(1):25-36 (in Chinese with English Abstract) |
Ling W. L., Duan R. C., Liu X. M., et al. 2010. U-Pb Dating of Detrital Zircons from the Wudangshan Group in the South Qinling and Its Geological Significance. Chinese Science Bulletin, 55(22):2440-2448 (in Chinese with English Abstract) |
Ling W. L., Gao S., Ouyang J. P., et al. 2002b. Time and Tectonic Setting of the Xixiang Group:Constraints from Zircon U-Pb Geochronology and Geochemistry. Science China Earth Sciences, 45(9):818-831. https://doi.org/10.3969/j.issn.1674-7313.2002.09.005 |
Ling W. L., Ren B. F., Duan R. C., et al. 2007. Zircon U-Pb Isotopic Geochronology of Wudangshan Group, Yaolinghe Group and Basic Intrusions and Its Geological Significance. Chinese Science Bulletin, 52(12):1445-1456 (in Chinese with English Abstract) |
Ling W. L., Ren B. F., Duan R. C., et al. 2008. Timing of the Wudangshan, Yaolinghe Volcanic Sequences and Mafic Sills in South Qinling:U-Pb Zircon Geochronology and Tectonic Implication. Science Bulletin, 53(14):2192-2199 (in Chinese with English Abstract) |
Liu L., Liao X. Y., Wang Y. W., et al. 2016. Early Paleozoic Tectonic Evolution of the North Qinling Orogenic Belt in Central China:Insights on Continental Deep Subduction and Multiphase Exhumation. Earth-Science Reviews, 159:58-81. https://doi.org/10.1016/j.earscirev.2016.05.005 |
Loucks R. R.. 1990. Discrimination of Ophiolitic from Nonophiolitic Ultramafic-Mafic Allochthons in Orogenic Belts by the Al/Ti Ratio in Clinopyroxene. Geology, 18(4):346. https://doi.org/10.1130/0091-7613(1990)018<0346:doofnu>2.3.co; 2 |
Lu S. N., Yu H. F., Li H. K., et al. 2009. Precambrian Geology of the West and Middle Central China Orogen. Geological Publishing House, Beijing. 76-98 (in Chinese) |
Lu X. X., Dong Y., Wei X. D., et al. 1999. Timing and Tectonic Significance of Tuwushan Type A Granite in East Qinling. Chinese Science Bulletin, 440:979-978 (in Chinese with English Abstract) |
Ludwig K. R.. 2003. ISOPLOT 3.0:A Geochronological Toolkit for Microsoft Excel. Berkeley Geochronology Center. Spercial Publication, No. 4. US Geologic Survey Open File Report, 39:91-445 |
Mattauer M., Matte P., Malavieille J., et al. 1985. Tectonics of the Qinling Belt:Build-up and Evolution of Eastern Asia. Nature, 317(6037):496-500. https://doi.org/10.1038/317496a0 |
Meng Q. R., Zhang G. W.. 1999. Timing of Collision of the North and South China Blocks:Controversy and Reconciliation. Geology, 27(2):123. https://doi.org/10.1130/0091-7613(1999)027<0123:tocotn>2.3.co; 2 |
Meng Q. R., Zhang G. W.. 2000. Geologic Framework and Tectonic Evolution of the Qinling Orogen, Central China. Tectonophysics, 323(3/4):183-196. https://doi.org/10.1016/s0040-1951(00)00106-2 |
Nie H., Yao J., Wan X., et al. 2016. Precambrian Tectonothermal Evolution of South Qinling and Its Affinity to the Yangtze Block:Evidence from Zircon Ages and Hf-Nd Isotopic Compositions of Basement Rocks. Precambrian Research, 286:167-179. https://doi.org/10.1016/j.precamres.2016.10.005 |
Nie H., Ye R. S., Cheng H., et al. 2019. Neoproterozoic Intrusions along the Northern Margin of South Qinling, Central China:Geochemistry, Zircon Ages, and Tectonic Implications. Precambrian Research, 334:105406. https://doi.org/10.1016/j.precamres.2019.105406 |
Pearce J. A., Norry M. J.. 1979. Petrogenetic Implications of Ti, Zr, Y, and Nb Variations in Volcanic Rocks. Contributions to Mineralogy and Petrology, 69(1):33-47. https://doi.org/10.1007/bf00375192 |
Price R. C., Gray C. M., Wilson R. E., et al. 1991. The Effects of Weathering on Rare-Earth Element, Y and Ba Abundances in Tertiary Basalts from Southeastern Australia. Chemical Geology, 93(3/4):245-265. https://doi.org/10.1016/0009-2541(91)90117-a |
Ratschbacher L., Franz L., Enkelmann E., et al. 2006. The Sino-Korean-Yangtze Suture, the Huwan Detachment, and the Paleozoic-Tertiary Exhumation of (Ultra) High-Pressure Rocks along the Tongbai-Xinxian-Dabie Mountains. Special Paper of the Geological Society of America, 403:45-75. https://doi.org/10.1130/2006.2403(03) |
Ratschbacher L., Hacker B. R., Calvert A., et al. 2003. Tectonics of the Qinling (Central China):Tectonostratigraphy, Geochronology, and Deformation History. Tectonophysics, 366(1/2):1-53. https://doi.org/10.1016/s0040-1951(03)00053-2 |
Ringwood A. E.. 1975. Composition and Petrology of the Earth's Mantle. McGraw-Hill Inc., London, New York and Sydney. 618 |
Rudnick R. L., Gao S.. 2003. The Composition of the Continental Crust. In: Holland H. D., Turekian K. K., eds., The Crust Treatise on Geochemistry. Elsevier, Oxford. 3: 1-64 |
Saunders A. D., Storey M., Kent R. W., et al. 1992. Consequences of Plume -Lithosphere Interactions. In:Storey B. C., Alabaster T., Pankhurst R. J., eds., Magmatism and the Causes of Continental Breakup. Geological Society Special Publications No. 68, 41-60. https://doi.org/10.1144/gsl.sp.1992.068.01.04 |
Shen J., Zhang Z. Q., Liu D. Y.. 1997. Sm-Nd, Rb-Sr, 40Ar/39Ar, 207Pb/206Pb Age of the Douling Metamorphic Complex from Eastern Qinling Orogenic Belt. Acta Geoscientia Sinica, 18(3):248-254 (in Chinese with English Abstract) |
Shi Y., Yu J. H., Santosh M.. 2013. Tectonic Evolution of the Qinling Orogenic Belt, Central China:New Evidence from Geochemical, Zircon U-Pb Geochronology and Hf Isotopes. Precambrian Research, 231:19-60. https://doi.org/10.1016/j.precamres.2013.03.001 |
Spera F. J., Bohrson W. A.. 2004. Open-System Magma Chamber Evolution:an Energy-Constrained Geochemical Model Incorporating the Effects of Concurrent Eruption, Recharge, Variable Assimilation and Fractional Crystallization (EC-E'RAχFC). Journal of Petrology, 45(12):2469-2479. https://doi.org/10.1093/petrology/egh072 |
Su C. Q., Hu J. M., Li Y., et al. 2006. The Existence of Two Different Tectonic Attributes in Yaolinghe Group in South Qinling Region. Acta Petrologica et Mineralogica, 25(4):287-298 (in Chinese with English Abstract). https://doi.org/10.3969/j.issn.1000-6524.2006.04.004 |
Sun S. S., McDonough W. F.. 1989. Chemical and Isotopic Systematics of Oceanic Basalts:Implications for Mantle Composition and Processes. Geological Society, London, Special Publications, 42(1):313-345. https://doi.org/10.1144/gsl.sp.1989.042.01.19 |
Thorpe R. S., Francis P. W., O'Callaghan L., et al. 1984. Relative Roles of Source Composition, Fractional Crystallization and Crustal Contamination in the Petrogenesis of Andean Volcanic Rocks. Philosophical Transactions of the Royal Society A:Mathematical, Physical and Engineering Sciences, 310(1514):675-692. https://doi.org/10.1098/rsta.1984.0014 |
Wang J. R., Pan Z. J., Zhang Q., et al. 2016. Intra-Continental Basalt Data Mining:The Diversity of Their Constituents and the Performance in Basalt Discrimination Diagrams. Acta Petrologica Sinica, 32(7):1919-1933 (in Chinese with English Abstract) |
Wang K., Plank T., Walker J. D., et al. 2002. A Mantle Melting Profile across the Basin and Range, SW USA. Journal of Geophysical Research:Solid Earth, 107(B1):ECV 5-1-ECV 5-21. https://doi.org/10.1029/2001jb000209 |
Wang R. R., Xu Z. Q., Santosh M.. 2019. Neoproterozoic Magmatism in the Northern Margin of the Yangtze Block, China:Implications for Slab Rollback in a Subduction-Related Setting. Precambrian Research, 327:176-195. https://doi.org/10.1016/j.precamres.2019.03.003 |
Wang Y. L., Zhang C. J., Xiu S. Z.. 2001. Th/Hf-Ta/Hf Identification of Tectonic Setting of Basalts. Acta Petrologica Sinica, 17(3):413-421 (in Chinese with English Abstract) |
Wilson M.. 1989. Igneous Petrogenesiss a Global Tectonic Approach. Unwin Hyman, London. 466. https: //doi.org/10.1007/978-94-010-9388-0 |
Winchester J. A., Floyd P. A.. 1977. Geochemical Discrimination of Different Magma Series and Their Differentiation Products Using Immobile Elements. Chemical Geology, 20:325-343. https://doi.org/10.1016/0009-2541(77)90057-2 |
Windley B. F.. 1989. The Evolving Continents. China University of Geosciences Press, Wuhan. 45-147 |
Wood D. A., Joron J. L., Treuil M.. 1979. A Re-Appraisal of the Use of Trace Elements to Classify and Discriminate between Magma Series Erupted in Different Tectonic Settings. Earth and Planetary Science Letters, 45(2):326-336. https://doi.org/10.1016/0012-821x(79)90133-x |
Workman R. K., Hart S. R.. 2005. Major and Trace Element Composition of the Depleted MORB Mantle (DMM). Earth and Planetary Science Letters, 231(1/2):53-72. https://doi.org/10.1016/j.epsl.2004.12.005 |
Wu Y. B., Zhou G. Y., Gao S., et al. 2014. Petrogenesis of Neoarchean TTG Rocks in the Yangtze Craton and Its Implication for the Formation of Archean TTGs. Precambrian Research, 254:73-86. https://doi.org/10.1016/j.precamres.2014.08.004 |
Xia L. Q.. 2014. The Geochemical Criteria to Distinguish Continental Basalts from Arc Related Ones. Earth-Science Reviews, 139:195-212. https://doi.org/10.1016/j.earscirev.2014.09.006 |
Xia L. Q., Xia Z. C., Li X. M., et al. 2008. Petrogenesis of the Yaolinghe Group, Yunxi Group, Wudangshan Group Volcanic Rocks and Basic Dyke Swarms from Eastern Part of the South Qinling Mountains. Northwestern Geology, 41(3):1-29 (in Chinese with English Abstract) |
Xiong F. H., Meng Y. K., Yang J. S., et al. 2020. Geochronology and Petrogenesis of the Mafic Dykes from the Purang Ophiolite:Implications for Evolution of the Western Yarlung-Tsangpo Suture Zone, Southwestern Tibet. Geoscience Frontiers, 11(1):277-292. https://doi.org/10.1016/j.gsf.2019.05.006 |
Xue Y. Y.. 2018. Granitic Magmatism and Crustal Evolution in Baoji-Taibai Area of the Qinling Orogenic Belt: [Dissertation]. University of Science and Technology of China, Hefei. 67-90 (in Chinese with English Abstract) |
Yan J. M., Sun G. S., Sun F. Y., et al. 2019. Geochronology, Geochemistry, and Hf Isotopic Compositions of Monzogranites and Mafic-Ultramafic Complexes in the Maxingdawannan Area, Eastern Kunlun Orogen, Western China:Implications for Magma Sources, Geodynamic Setting, and Petrogenesis. Journal of Earth Science, 30(2):335-347. https://doi.org/10.1007/s12583-018-1203-8 |
Yang B. H., Zhang C. L., Li L.. 2011. Sr-Nd-Pb Isotopic Characteristics of the Granitoids in the Douling Complexes, Eastern Qinling, China and Its Geological Significance. Geological Bulletin of China, 30(2-3):439-447 (in Chinese with English Abstract) |
Yuan H. L., Gao S., Dai M. N., et al. 2008. Simultaneous Determinations of U-Pb Age, Hf Isotopes and Trace Element Compositions of Zircon by Excimer Laser-Ablation Quadrupole and Multiple-Collector ICP-MS. Chemical Geology, 247(1/2):100-118. https://doi.org/10.1016/j.chemgeo.2007.10.003 |
Yuan X. C., Xu M. C., Tang W. B., et al. 1994. Eastern Qinling Seismic Reflection Profiling. Acta Geophysica Sinica, 37(6):749-758 (in Chinese with English Abstract) |
Zhang C. L., Li M., Wang T., et al. 2004. U-Pb Zircon Geochronology and Geochemistry of Granitoids in the Douling Group in the Eastern Qinling. Acta Geologica Sinica——English Edition, 78(1):83-95. https://doi.org/10.1111/j.1755-6724.2004.tb00678.x |
Zhang C. L., Zhou D. W., Jin H. L., et al. 1999a. Study on the Sr, Nd, Pb and O Isotopes of Basic Dyke Swarms in the Wudang Block and Basic Volcanics of the Yaolinghe Group. Chinese Journal of Geochemistry, 20(3):193-200 (in Chinese with English Abstract) |
Zhang C. L., Zhou D. W., Liu Y. Y.. 1999b. Geochemistry of Basic Dykes in Wudang Block and Its Tectonic Significance. Chinese Journal of Geochemistry, 20(4):315-323 (in Chinese with English Abstract) |
Zhang G. W.. 1987. Formation and Evolution of the Qinling Orogenic Belt. Northwest University Press, Xi'an. 1-191 (in Chinese) |
Zhang G. W.. 2001. Qinling Orogenic Belt and Continental Dynamics. Science Press, Beijing. 1-855 (in Chinese) |
Zhang G. W., Meng Q. R., Lai S. C.. 1995. Tectonics and Structure of Qinling Orogenic Belt. Science in China (Series B), 25(9):994-1003 (in Chinese with English Abstract) |
Zhang G. W., Meng Q. R., Yu Z. P., et al. 1996. Orogenesis and Dynamics of the Qinling Orogen. Science China Earth Sciences, 39(3):225-234. https://doi.org/10.1360/yd1996-39-3-225 |
Zhang G. W., Yu Z. P., Sun Y., et al. 1989. The Major Suture Zone of the Qinling Orogenic Belt. Journal of Southeast Asian Earth Sciences, 3(1/2/3/4):63-76. https://doi.org/10.1016/0743-9547(89)90010-x |
Zhang H. F., Ouyang J. P., Ling W. L., et al. 1996. Tectonic Division of Douling Massif of East Qinling by Pb Isotopic Compositional Characteristics. Earth Science, 21(5):487-490 (in Chinese with English Abstract) |
Zhang J., Zhang H. F., Li L.. 2018. Neoproterozoic Tectonic Transition in the South Qinling Belt:New Constraints from Geochemistry and Zircon U-Pb-Hf Isotopes of Diorites from the Douling Complex. Precambrian Research, 306:112-128. https://doi.org/10.1016/j.precamres.2017.12.043 |
Zhang S. G., Wei C. J., Zhao Z. R., et al. 1996. Formation and Metamorphic Evolution of the Douling Complex from the East Qinling Mountains. Science China Earth Sciences, 39:80-86. https://doi.org/10.1360/yd1996-39-S1-80 |
Zhang S. G., Zhang Z. Q., Song B., et al. 2004. Existence of Neoarchean Materials in the Douling Complex, Eastern Qinling:Evidence from U-Pb SHRIMP and Sm-Nd Geochronology. Acta Geologica Sinica, 78:800-806 (in Chinese with English Abstract) |
Zhang Y. R.. 1985. The Ancient Tongbai-Xinyang Ophiolite Zone and Melanges. Regional Geology of China, 3:149-164 (in Chinese with English Abstract) |
Zhang Z. Q.. 2002. Isotopic Geochronology of Metamorphic Strata in South Qinling. In: Zhang G. W., Tang S. H., eds., Geology Press, Beijing (in Chinese) |
Zhang Z. Q., Song B., Tang S. H., et al. 2004. Age and Material Composition of the Foping Metamorphic Crystal Line Complex in the Qinling Mountains:SHRIMP Zircon U-Pb and Whole-Rock Sm-Nd Geochronology. Chinese Geology, 31 (2):161-168 (in Chinese with English Abstract) |
Zhao Z. R., Wan Y. S., Zhang S. G., et al. 1995. The Geochemical Features of the Douling Metamorphic Complex. Acta Petrologica Sinica, 11(2):148-159 (in Chinese with English Abstract) |
Zhou D. W., Zhang C. L., Liu Y. Y.. 1998. Study on Basic Dyke Swarms Developed in the Basement in the Continental Orogeny:An Example from Wudang Block in Southern Qingling. Advance in Earth Sciences, 13(3):151-156 (in Chinese with English Abstract) |
Zhu X. Y., Chen F., Yang L., et al. 2009. Zircon Hf Isotopic Composition and Source Characteristics of the Wudang Group in the Qinling Orogenic Belt, Western Henan Province. Acta Petrologica Sinica, 25:3017-3028 (in Chinese with English Abstract) |
1. | Yunpeng Dong, Bo Hui, Shengsi Sun, et al. Neoproterozoic tectonic evolution and proto-basin of the Yangtze Block, China. Earth-Science Reviews, 2024, 249: 104669. doi:10.1016/j.earscirev.2023.104669 | |
2. | Jia Liu, Yajun Xu, Peter A. Cawood, et al. Evidence for, and significance of, the Neoproterozoic Xuefeng Orogeny, South China. Precambrian Research, 2024, 411: 107532. doi:10.1016/j.precamres.2024.107532 | |
3. | Jibiao Zhang, Xiaozhong Ding, Yanxue Liu, et al. The ca. 1.13–0.92 Ga magmatism in the western Yangtze Block, South China: Implications for tectonic evolution and paleogeographic reconstruction. Precambrian Research, 2023, 386: 106961. doi:10.1016/j.precamres.2023.106961 | |
4. | Wenhao Zhao, Qiuli Li, Yu Liu, et al. Long-Term Reproducibility of SIMS Zircon U-Pb Geochronology. Journal of Earth Science, 2022, 33(1): 17. doi:10.1007/s12583-021-1549-1 | |
5. | Limin Zhao, Yilong Li, Chao Rong, et al. Geochemical and zircon U-Pb-Hf isotopic study of volcanic rocks from the Yaolinghe Group, South Qinling orogenic belt, China: Constraints on the assembly and breakup of Rodinia. Precambrian Research, 2022, 371: 106603. doi:10.1016/j.precamres.2022.106603 | |
6. | Xiao-Fei Qiu, Qiong Xu, Tuo Jiang, et al. Petrogenesis and tectonic significance of the middle Neoproterozoic highly fractionated A-type granite in the South Qinling block. Geological Magazine, 2021, 158(10): 1891. doi:10.1017/S001675682100042X | |
7. | Guichun Liu, Jing Li, Xin Qian, et al. Geochronological and geochemical constraints on the petrogenesis of late Mesoproterozoic mafic and granitic rocks in the southwestern Yangtze Block. Geoscience Frontiers, 2021, 12(1): 39. doi:10.1016/j.gsf.2020.07.005 | |
8. | Hongli Zhu, Renqiang Liao, He Liu, et al. Calcium isotopic fractionation during magma differentiation: Constraints from volcanic glasses from the eastern Manus Basin. Geochimica et Cosmochimica Acta, 2021, 305: 228. doi:10.1016/j.gca.2021.05.032 |