Scholarly article on topic 'Neoarchean (2.5–2.8Ga) crustal growth of the North China Craton revealed by zircon Hf isotope: A synthesis'

Neoarchean (2.5–2.8Ga) crustal growth of the North China Craton revealed by zircon Hf isotope: A synthesis Academic research paper on "Materials engineering"

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Abstract of research paper on Materials engineering, author of scientific article — Andong Wang, Yican Liu

Abstract The crustal growth of the North China Craton (NCC) during the Neoarchean time (2.5–2.8Ga) is a hotly controversial topic, with some proposing that the main crustal growth occurred in the late Neoarchean (2.5–2.6Ga), in agreement with the time of the magmatism, whereas others suggest that the main crustal accretion took place during early Neoarchean time (2.7–2.8Ga), consistent with the time of crustal-formation of other cratons in the world. Zircon U-Pb ages and Hf isotope compositions can provide rigorous constraints on the time of crustal growth and the evolution and tectonic division of the NCC. In this contribution, we make a comprehensive review of zircon Hf isotope data in combination with zircon U-Pb geochronology and some geochemistry data from various divisions of the NCC with an aim to constrain the Neoarchean crustal growth of the NCC. The results suggest that both 2.7–2.8Ga and 2.5–2.6Ga crustal growth are distributed over the NCC and the former is much wider than previously suggested. The Eastern block is characterized by the main 2.7–2.8Ga crustal growth with local new crustal-formation at 2.5–2.6Ga, and the Yinshan block is characterized by ∼2.7Ga crustal accretion as revealed by Hf-isotope data of detrital zircons from the Zhaertai Group. Detrital zircon data of the Khondalite Belt indicate that the main crustal growth period of the Western block is Paleoproterozoic involving some ∼2.6Ga and minor Early- to Middle-Archean crustal components, and the crustal accretion in the Trans-North China Orogen (TNCO) has a wide age range from 2.5Ga to 2.9Ga with a notable regional discrepancy. Zircon Hf isotope compositions, coupled with zircon ages and other geochemical data suggest that the southern margin may not be an extension of the TNCO, and the evolution and tectonic division of the NCC is more complex than previously proposed, probably involving multi-stage crustal growth and subduction processes. However, there is no doubt that 2.7–2.8Ga magmatism and crustal-formation are more widely distributed than previously considered, which is further supported by the data of zircons from Precambrian lower crustal rocks, overlying sedimentary cover, modern river sediments and Late Neoarchean syenogranites.

Academic research paper on topic "Neoarchean (2.5–2.8Ga) crustal growth of the North China Craton revealed by zircon Hf isotope: A synthesis"

GEOSCIENCE FRONTIERS 3(2) (2012) 147-173

available at www.sciencedirect.com China University of Geosciences (Beijing)

GEOSCIENCE FRONTIERS

journal homepage: www.elsevier.com/locate/gsf

GSF REVIEW

Neoarchean (2.5—2.8 Ga) crustal growth of the North China Craton revealed by zircon Hf isotope: A synthesis

Andong Wang*, Yican Liu

CAS Key Laboratory of Crust-Mantle Materials and Environments, School of Earth and Space Sciences, University of Science and Technology of China, Hefei 230026, China

Received 31 July 2011; accepted 27 October 2011 Available online 16 December 2011

KEYWORDS

Zircon; U-Pb dating; Hf isotope; Neoarchean crustal growth;

North China Craton

Abstract The crustal growth of the North China Craton (NCC) during the Neoarchean time (2.5—2.8 Ga) is a hotly controversial topic, with some proposing that the main crustal growth occurred in the late Neoarchean (2.5—2.6 Ga), in agreement with the time of the magmatism, whereas others suggest that the main crustal accretion took place during early Neoarchean time (2.7—2.8 Ga), consistent with the time of crustal-formation of other cratons in the world. Zircon U-Pb ages and Hf isotope compositions can provide rigorous constraints on the time of crustal growth and the evolution and tectonic division of the NCC. In this contribution, we make a comprehensive review of zircon Hf isotope data in combination with zircon U-Pb geochro-nology and some geochemistry data from various divisions of the NCC with an aim to constrain the Neoarchean crustal growth of the NCC. The results suggest that both 2.7—2.8 Ga and 2.5—2.6 Ga crustal growth are distributed over the NCC and the former is much wider than previously suggested. The Eastern block is characterized by the main 2.7—2.8 Ga crustal growth with local new crustal-formation at 2.5—2.6 Ga, and the Yinshan block is characterized by ~2.7 Ga crustal accretion as revealed by Hf-isotope data of detrital zircons from the Zhaertai Group. Detrital zircon data of the Khondalite Belt indicate that the main crustal growth period of the Western block is Paleoproterozoic involving some ~ 2.6 Ga and minor Early- to Middle-Archean crustal components, and the crustal accretion in the Trans-North China Orogen (TNCO) has a wide age range from 2.5 Ga to 2.9 Ga with a notable regional discrepancy. Zircon Hf isotope compositions, coupled with zircon ages and other geochemical data suggest that the southern margin may not be an extension of the TNCO, and the evolution and tectonic division of the NCC is more complex

* Corresponding author. Tel.: +86 551 3600367. E-mail address: adw008@mail.ustc.edu.cn (A. Wang). 1674-9871 © 2011, China University of Geosciences (Beijing) and Peking University. Production and hosting by Elsevier B.V. All rights reserved.

Peer-review under responsibility of China University of Geosciences (Beijing).

doi:10.1016/j.gsf.2011.10.006

than previously proposed, probably involving multi-stage crustal growth and subduction processes. However, there is no doubt that 2.7—2.8 Ga magmatism and crustal-formation are more widely distributed than previously considered, which is further supported by the data of zircons from Precambrian lower crustal rocks, overlying sedimentary cover, modern river sediments and Late Neoarchean syenogranites. © 2011, China University of Geosciences (Beijing) and Peking University. Production and hosting by Elsevier B.V. All rights reserved.

1. Introduction

Up to now, at least three different models have been put forward to depict the crustal growth and evolution history of the Earth. The first is that the volume of continental crust has increased linearly or progressively with time (Hurley and Rand, 1969; Moorbath, 1978), as evidenced by the present continental crust of various ages. The second argues that most of the mass of present continents formed in the first billion years of the Earth's history with only minor subsequent growth (no growth model) (Armstrong, 1981), implying that the present crust might be remelting or differentiation of the pre-existing ancient continental crust. In contrast to these two models, in recent years voluminous in-situ zircon U-Pb ages and radiogenic isotope model ages of granitoids and modern river sediments have shown several striking age-peaks. This has led many geologists to argue for a third model in which the continental crust has grown throughout geological time with several pulses (Condie, 1998, 2000; Rion et al., 2004; Condie et al., 2009; Condie and Aster, 2010; Iizuka et al., 2010; Kroner, 2010; Safonova et al., 2010).

The North China Craton (NCC) is one of the oldest cratons in the world and contains ancient crust remnants as old as 3.8 Ga in the eastern part (Liu et al., 1992, 2007, 2008; Song et al., 1996; Zheng et al., 2004a; Wu et al., 2005a,b, 2008a; Wilde et al., 2008; Wan et al., 2009a; Nutman et al., 2009, 2011). In the past two decades, numerous geochronology studies, especially in-situ zircon U-Pb ages suggest that the most strongest tectono-thermal event in the NCC occurred in ~ 2.5 Ga (e.g., Guan et al., 2002; Zhao et al., 2002, 2008; Kroner et al., 1998, 2005a,b; Wilde et al., 2004, 2005; Guo et al., 2005; Shen et al., 2005; Geng et al., 2006, 2010, 2011; Liu et al., 2009a,b, 2011a; Wang et al., 2010a, 2011; Zhang et al., 2011a). Accordingly, some geologists have presumed that an important continental crustal growth time for the NCC is ~ 2.5 Ga, which is different from that of the other cratons with a main peak at -2.7 Ga (Windley, 1995; Gao et al., 2004; Wang et al., 2004; Geng et al., 2010, 2011). However, published whole-rock Sm-Nd isotopic data indicate that the major crustal growth in the NCC took place at 2.7-2.8 Ga (Wu et al., 2005b), and the -2.5 Ga crustal growth is subdominant and may represent the remeling or differentiation of the older crust formed at 2.7-2.8 Ga. In fact, in many cases whole-rock Nd model ages cannot reflect the formation ages of extracting juvenile crust from depleted mantle due to Sm-Nd mobility and mixing or/and contamination of ancient crustal materials (Liu et al., 2009b; Iizuka et al., 2010; Kroner, 2010). For instance, in some cases where mantle melt underplates the overlying continental lithosphere and interacts with pre-existing older crustal materials before differentiating further, marked decoupling between zircon and Nd model ages may occur, depending on the age of crustal materials and the degree of crust-mantle interaction. In this regard, the whole-rock Nd model age no longer reflects the time of extraction of a melt from the depleted mantle but merely represents a mean crustal residence age (Arnde and Goldstein, 1987; Kroner, 2010). In addition, zircon age-

peaks in age spectra are not equal to the periods of continental crustal growth. Condie et al. (2009) found that the existing Nd and Hf isotope database do not support widespread production of juvenile continental crust during the Neoproterozoic (800—600 Ma) and Greenvillian (1200—1000 Ma), which represent marked age-peaks in zircon U-Pb age spectra. In contrast to other isotope systems, the zircon Lu-Hf isotopic system has a relatively high closure temperature and low Lu/Hf ratios, which makes zircon Lu-Hf isotopic analyses an ideal and reliable method for investigating early crustal growth in combination with zircon U-Pb ages and other geochemical data (Amelin et al., 1999; Zheng et al., 2005; Liu et al., 2009c; Iizuka et al., 2010; Jiang et al., 2010; Safonova et al., 2010).

In the past several years, great achievements have been made in the study of the NCC, one of which is the tectonic subdivision and evolution of the craton (Zhao et al., 1999, 2000a,b, 2001, 2004, 2005, 2011; Zhai et al., 2000, 2010; Wilde et al., 2002; Kusky and Li, 2003; Wang et al., 2004, 2010b; Zhai, 2004; Polat et al., 2005; Faure et al., 2007; Kusky et al., 2007a,b; Li and Kusky, 2007; Trap et al., 2007, 2008, 2009a,b, 2011; Zhao, 2009; Wang, 2009; Santosh, 2010; Santosh et al., 2011; Zhai and Santosh, 2011; Zhang et al., 2011d). In terms of substantive structural, geological, geochemical, geochronological and p-T data, the basement of the NCC can be tectonically divided into two discrete blocks named the Eastern block (EB, also called Yanliao block by Santosh, 2010) and Western block (WB) that are separated by the Paleoproterozoic Trans-North China Orogen (TNCO). Although numerous investigations about the timing and tectonic processes of the Paleoproterozoic amalgamation of the NCC have been made, our knowledge of the pre-collision history of the EB and WB remains poorly understood and controversial, especially in terms of their crustal-formation ages and mechanisms (e.g., Wang et al., 2004; Zhai, 2004; Zhao, 2009; Geng et al., 2010, 2011). Recently, Wu et al. (2005b) reviewed whole-rock Nd isotopic compositions and model ages of the EB and WB and TNCO and obtained many important conclusions about the crustal-formation and tectonic subdivision. However, at that time, zircon Hf isotope studies have not been fully carried out (Zheng et al., 2004a, 2004b). From then on, a large amount of zircon Hf analyses have been published and it is opportune to review these data with an aim to better trace the crustal growth and evolution of the NCC.

2. The reason to choose zircons

It is well known that zircon is a ubiquitous accessory mineral in igneous, sedimentary and metamorphic rocks, and has high mechanical stability and chemical resistance. Its ability to concentrate U and exclude Pb provides the basis of U-Pb dating. More importantly, zircon generally has a relatively high U-Pb diffusion closure temperature and is an ideal mineral for geochronology (Lee et al., 1997; Cherniak and Watson, 2000; Wu and Zheng, 2004). Recently, Gardes and Montel (2009) have

provided a new theoretical model for diffusive isotope loss that assesses the opening and resetting of radiochronometers during metamorphism of various minerals. The opening temperature defines the beginning temperature of daughter isotope loss, and the temperature at which the daughter isotope is completely lost is the resetting temperature. Of all the evaluated minerals, zircon has the highest opening temperature of >900 °C depending on its grain size, and the highest resetting temperature of about 1400 °C. All these merits make zircon an ideal and reliable mineral for dating various thermal events, even for the extreme metamorphism like ultrahigh-temperature (UHT) and ultrahigh pressure (UHP) metamorphism (e.g., Moller et al., 2003; Hermann et al., 2001; Santosh et al., 2009; Liu et al., 2011f). In addition to the U-Th-Pb isotope system, zircon possesses another radiogenic Lu-Hf isotope system, which is essential for depicting crustal growth and evolution (Vervoort and Patchett, 1996; Griffin et al., 1999; Vervoort and Blichert-Toft, 1999; Zheng et al., 2005, 2006). The geochemical behavior of Hf is so similar to that of Zr that it is easily concentrated and bound in the zircon crystal lattice, whereas the REEs including Lu are far less compatible. Therefore, zircons generally have very low Lu/Hf ratios (typically < 0.001), so that in-situ radiogenic Hf isotope growth is virtually negligible, which is favorable for tracing crustal evolution and distinguishing magmatism from metamorphism.

In addition, zircon also has many other advantageous aspects. For example, empirical studies have established that oxygen diffusion in zircon is sufficiently sluggish even through long-term metamorphism and crustal fusion (King et al., 1998). Zircon has high capacity to contain trace elements, and the trace elements in igneous zircon including contents and ratios can be used to indicate the composition and crystallization environment of the magma from which they crystallized (Belousova et al., 2002). Thus, both isotopes and trace elements can provide rigorous constraints on the magmatic zircon evolution from mantle-derived precursors or from mixed juvenile and recycled sources (Bibikova, 2003; Hawkesworth and Kemp, 2006; Zheng et al., 2006; Wilde et al., 2008; Liu et al., 2009c).

Regarding the Hf analytical technique, in the past few years following by pioneering studies by Griffin et al. (1999, 2002), analysis of Hf isotopes in zircon by laser ablation has become almost mature, although the technique is still undergoing refinement (Woodhead et al., 2004; Hawkesworth and Kemp, 2006). The interference correction and ablation effects during zircon Hf isotope analyses are well understood. Another problem is to concern the stability and closure temperature of the Lu-Hf isotope system when using Hf isotope data to explain zircon genesis and crustal evolution. Voluminous investigations indicate that the zircon Lu-Hf isotope system has high stability, and it may be higher than zircon U-Pb isotope system (e.g., Zheng et al., 2005, 2007; Wan et al., 2009b). It has been confirmed by other nature researches and experimental data. For instance, for granite samples showing a single magmatic zircon age-group, no relationship between the Hf isotope composition and the degree of discordance on U-Pb concordia diagrams is observed, where the discordance of zircon ages is probably ascribed to radiogenic Pb loss (Hawkesworth and Kemp, 2006). Experimental measurements on cation diffusivity in zircon also indicate that Hf diffuses much more slowly than Pb and HREE but a little faster than U and Th (Cherniak and Watson, 2003). Thus the zircon Hf isotope composition is more refractory to metamorphic resetting by diffusion than zircon U-Pb isotope compositions, and meta-morphically recrystallized zircon is still capable of faithfully

recording its protolith Hf isotope composition (Zheng et al., 2005). Therefore, although the metamorphic effect on zircon Hf isotope is complex, especially for metamorphic zircon overgrowths that formed in response to younger metamorphic episodes due to their very different Hf isotope ratios, the zircon Lu-Hf isotope system is still an important tool in constraining the nature and timing of metamorphism and trace crustal growth and evolution (Vervoort and Patchett, 1996; Vervoort and Blichert-Toft, 1999; Wu et al., 2008b).

How to define "juvenile crust", "reworked crust" and "crustal growth" is difficult (Zheng et al., 2005; Belousova et al., 2010; Diwu et al., 2010). It is reasonable to define "juvenile crust" is that magmas forming the crust were generated directly from depleted mantle, and that "reworked crust" represents the remelting of ancient crust. However, when the time interval between the formation and remelting is short (instant reworking), the model age is most probably regarded as the timing of the corresponding crustal growth. Thus, the model ages of both juvenile crust and instant reworked crust can be considered as the timing of crustal growth. Belousova et al. (2010) defined that "zircons possessing eHf > 0.75 times of the Hf of the depleted mantle curve, which is equivalent to 75% of the MORB range", can be deciphered as "juvenile crust" or "crustal growth". Thus, this method is considered to be a reasonable and practical approach to deal with Hf isotope data when applying zircon Hf isotope data to trace crustal growth.

In this contribution, we firstly introduce the geological setting of the NCC, then compile zircon Hf isotope data from the basement rocks, and finally discuss the crustal growth and evolution of the NCC, and provide some constraints on the tectonic subdivision of the NCC. Recently, Wan et al. (2011a,b) have compiled a total of 7586 zircon ages from basement rocks over the entire NCC and have made a comprehensive review about the zircon ages and geochemistry of late Neoarchean syenogranites in the NCC. Zhang et al. (2011a) have comprehensively reviewed U-Pb geochronology and Hf isotope of zircons from granulite xenoliths entrained in Phanerozoic magmatic rocks and inherited xenocrysts from associated lower crust rocks from both the EB and Hannuoba region in the TNCO. All these data provide us with invaluable information to better understand the crustal growth and evolution of the NCC.

3. Geological background

The NCC refers to the Chinese part of the Sino-Korean Craton. It is the oldest and largest known craton in China and contains ancient crustal relicts as old as 3.6-3.8 Ga (e.g., Liu et al., 1992; Song et al., 1996; Zheng et al., 2004a; Wu et al., 2005a,b, 2008a; Nutman et al., 2009, 2011; Wilde et al., 2008; Wan et al., 2009a) with an area of about 1,500,000 km2. The craton is bounded to the west and north by Early Paleozoic Qilianshan Orogen and the Late Paleozoic Tianshan-Xing'an-Mongolian Orogen, respectively, and is separated from the Yangtze Craton in the south by the Qinling-Dabie-Su-Lu UHP metamorphic belt.

Traditionally, the NCC was considered as to be composed of a uniform Archean-Paleoproterozoic crystalline basement, overlain by younger cover (Huang, 1977). However, in the past decade, extensive lithological, structural, geochronological and geochem-ical investigations have led to a three-fold tectonic division of the NCC (Zhao et al., 1998, 1999, 2000a,b, 2001; Kusky and Li, 2003; Polat et al., 2005; Li and Kusky, 2007; Santosh, 2010; Kusky,

2011; Santosh et al., 2011). Specifically, the NCC can be tecton-ically divided into two discrete Eastern and Western blocks (EB and WB) and the intervening Paleoproterozoic Trans-North China Orogen (TNCO). The Archean basement rocks of the EB and WB are characterized by anticlockwise p-T paths involving isobaric cooling (IBC) with metamorphism occurring at -2.5 Ga, whereas the Archean to Paleoproterozoic basement rocks from the TNCO are characterized by clockwise p-T paths involving near-isothermal decompression (ITD) with metamorphism taking place at - 1.85 Ga. Additional data collected from the whole craton have led to further tectonic division of the WB into the Yinshan block in the north and the Ordos block in the south separated by the Paleoproterozoic Khondalite Belt (also called the Inner Mongolia Suture Zone (IMSZ) by Santosh, 2010) (Zhao et al., 2005, 2010a, 2011; Zhao, 2009). The metamorphic evolution of the Khondalite Belt is also characterized by clockwise p-T paths involving near-isothermal decompression with the meta-morphic age of 1.92-1.95 Ga, a little earlier than the timing of collision between the EB and WB (Zhao et al., 2005, 2010a, 2010b, 2011; Zhao, 2009; Santosh et al., 2006, 2007, 2009, 2011; Yin et al., 2009, 2011; Wan et al., 2006a, 2009b; Li et al., 2011a; Liu et al., 2011e). Voluminous studies for the Jiao-Liao-Ji Belt suggest that this belt divides the EB into the Longgang block in the north and the Nangrim block in the south (Faure et al., 2004; Luo et al., 2004, 2006, 2008; Lu et al., 2004, 2006; Li et al.,

2005, 2006, 2007, 2011b; Zhou et al., 2008; Tam et al., 2011a,b; Zhao et al., 2011). Thus, the Archean to Palaeoproterozoic basement of the NCC consists of four micro-continental blocks (Yin-shan block, Ordos block, Longgang block, Nangrim block) and three Palaeoproterozoic orogenic belts (Khondalite Belt, Jiao-Liao-Ji Belt, Trans-North China Orogen) (Fig. 1, Zhao et al., 2005, 2011). It is noteworthy that other models have been put forward to explain the evolution and tectonic subdivision of the NCC involving different collisional ages/stages and subduction polarities (Zhai et al., 2000, 2010; Kusky and Li, 2003; Faure et al., 2004; Wang et al., 2004, 2010a,b; Zhai, 2004; Polat et al., 2005; Kusky et al., 2007a,b; Li and Kusky, 2007; Trap et al., 2007, 2008, 2009a,b, 2011; Wang, 2009; Santosh, 2010; Santosh et al., 2011; Zhai and Santosh, 2011). Following by the -1.85 Ga amalgamation, the NCC underwent a series of extensional and rifting events in its interior and margins during the time of 1.85-1.6 Ga, forming aulacogens and marginal rift basins with the emplacement of mafic-ultramafic dyke swarms, anorthosite-gabbro-mangerite-rapakivi granites (AGMR) and A-type granites, and eruption of super-high potassium volcanic rocks (e.g., Halls et al., 2000; Zhai et al., 2000; Lu et al., 2002, 2008; Peng et al., 2008; Zhang et al., 2007; Hou et al., 2008; Wang et al., 2008; He et al., 2009; Zhao et al., 2009; Peng 2010; Piper et al., 2011; and references therein).

The EB comprises the domains of eastern Hebei, Miyun-Chengde, western Liaoning, Anshan-Benxi, south Liaoning,

Figure 1 Tectonic subdivision of the North China Craton (after Zhao et al., 2005). Abbreviations of metamorphic complexes: CD—Chengde; DF—Dengfeng; EH—eastern Hebei; ES—eastern Shandong; GY—Guyang; HA—Huai'an; HL—Helanshan; JN—Jining; LL—Luliang; MY—Miyun; NH—northern Hebei; NL—northern Liaoling; QL—Qianlishan; SJ—southern Jilin; SL—southern Liaoning; TH—Taihua; WD—Wulashan—Daqingshan; WL—western Liaoning; WS—western Shandong; WT—Wutai; XH—Xuanhua; ZH—Zanhuang; ZT—Zhongtiao.

south Jilin, western Shandong and eastern Shandong (Zhao et al., 1998). The basement rocks of the EB are mainly dominated by a Late Archean lithological assemblage, with minor Early- to Middle-Archean rocks with ages being from 3.3 Ga to 3.8 Ga (Jahn et al., 1987, 1988; Liu et al., 1992; Song et al., 1996; Wan et al., 2009a; Nutman et al., 2009, 2011). The Late Archean basement rocks include 2.6—2.5 Ga TTG gneisses, mafic to ultramafic igneous intrusives and dykes, and ~ 2.5 Ga syntectonic charnockites and granites with minor ~2.5 Ga supracrustal rocks (Kroner et al., 1998; Zhao et al., 1998). All of them suffered greenschist to granulite-facies metamorphism at 2.48—2.50 Ga with anticlockwise IBC-type p-T paths (Wu et al., 2011). The Palaeoproterozoic Jiao-Liao-Ji Belt is located in the eastern margin of the EB, and consists of greenschist to lower amphibolite facies sedimentary and volcanic succession associated with some granites and mafic intrusions. The Jiao-Liao-Ji Belt is characterized by paired metamorphic zones and can be further divided into the northwestern zone of the North Liaohe, Laoling and Fenzishan Groups that have undergone medium-pressure-type clockwise p-T paths and the southeastern zone of the south Liaohe, Ji'an and Jingshan Groups that is characterized by low-pressure-type anticlockwise p-T paths (Zhao et al., 2005; 2011; Luo et al., 2008; Zhao, 2009; Li et al., 2011b). The tectonic nature of the Jiao-Liao-Ji Belt is controversial and different models have been proposed including intra-continental rifting, arc-continent or continent—continent collision, and rift-and-collision (Faure et al., 2004; Luo et al., 2004, 2006, 2008; Li et al., 2005, 2006, 2007, 2011b; Lu et al., 2006; Li and Zhao, 2007; Zhou et al., 2008; Tam et al., 2011a, 2011b; Zhao et al., 2011). More intergraded work is clearly required in the future.

The TNCO contains the Defeng, Fuping, Hengshan, Huai'an, Luliang, Wutai, Zanhuang, Taihua, north Hebei and Zhongtiao domains and is separated from the EB and WB by major faults. It is composed dominantly of Late Archean to Paleoproterozoic basement rocks metamorphosed from greenschist to granulite facies. On the basis of lithology and metamorphic grade, Zhao et al. (2000a,b) grouped the basement rocks into low-grade granite—greenstone belts containing the Dengfeng, Luuliang, Zhongtiao, Wutai and Zanhuang domains and high-grade gneisses including Taihua, Hengshan, Fuping and Huai'an domains. Emplacement of TTG and granitic plutons and eruption of mafic to felsic volcanic rocks took place mainly at 2.5—1.9 Ga with a main age-peak at ~2.5 Ga and a minor age-peak at ~2.1 Ga (e.g., Wilde et al., 1997, 2004; Zhao et al., 2000a,b, 2001, 2002, 2004, 2008; Guo et al., 2005; Kroner et al., 2005a,b, 2006). Metamorphism of the basement in the TNCO, regardless of their protolith age, composition and meta-morphic grade, is characteristically featured by clockwise ITD-type clockwise p-T paths involving collision between the EB and WB (Zhao et al., 2000a, 2010b; Xiao et al., 2010). Extensive geochro-nological studies based on zircon SHRIMP U-Pb, mineral Ar-Ar and Sm-Nd, and monazite U-Pb dating methods show that the timing of the metamorphism for the TNCO happened at ~ 1.85 Ga (Guo and Zhai, 2001; Guo et al., 2005; Liu et al., 2006a; Wan et al., 2006a,b; Wang et al., 2010a; Zhao et al., 2010b, 2011, and references therein). It is noteworthy that ~ 2.7 Ga and even older basement components and zircon ages are more widely distributed along the southern margin of the TNCO than in the middle and northern segments of the TNCO (Kroner et al., 1988; Gao et al., 2005a; Yang, 2008; Liu et al., 2009c; Diwu et al., 2010; Huang et al., 2010).

The WB is composed of the Ordos block in the south and the Yinshan block in the north separated by the Palaeoproterozoic

EW-trending Khondalite Belt that extends from Helanshan and Qianlishan in the west, through Daqingshan and Wulanshan in the central, to Jining in the east (Zhao et al., 1999, 2005, 2011; Zhao, 2009; Santosh, 2010; Santosh et al., 2011; Li et al., 2011a). The Ordos block is completely covered by the younger Ordos Basin (Wu et al., 1986). The Yinshan block is dominated by late Archean TTG gneisses and minor supracrustal rocks exposed in the Guyang and Wuchuan domains. All of them were meta-morphed to greenschist to granulite-facies grade at ~2.5 Ga and exhibit counter-clockwise IBC-type p-T paths (Zhao et al., 1999; and references therein). The Khondalite Belt was formed by collision between the Ordos and Yinshan blocks at 1.92—1.95 Ga (Yin et al., 2009, 2011; Zhao, 2009; Zhao et al., 2005, 2011; Santosh et al., 2006, 2007, 2009; Wan et al., 2006a, 2009a,b,c; Dong et al., 2007, 2009; Li et al., 2011a), and its metamorphic evolution is also characterized by clockwise ITD-type p-T paths (Zhao et al., 1999, 2005, 2011). Besides, ultrahigh-temperature (UHT) metamorphic rocks within the Khondalite Belt (also named as the Inner Mongolia Suture Zone (IMSZ) by Santosh,

2010) has also been widely investigated by various authors (Guo et al., 2006; Santosh et al., 2006, 2007, 2008, 2011; Liu et al., 2010; Jiao and Guo, 2011; Jiao et al., 2011; Tsunogae et al.,

2011).

In recent years, many investigations of zircon U-Pb and Hf isotope isotope from different blocks/domains have been conducted to unveil the craton's growth and evolution history. In this contribution, we compile published data and review the Neoarchean (2.8—2.5 Ga) crustal growth of the NCC. The Neoarchean can be further subdivided into Early Neoarchean (2.7—2.8 Ga) and late Neoarchean (2.5—2.6 Ga). Traditionally, it has been proposed that the main crustal growth period was at 2.5—2.6 Ga, consistent with the timing of Late Neoarchean magmatism; whereas another suggestion is that 2.7—2.8 Ga was also an important time of NCC's crustal growth. Available zircon Hf isotope data can provide rigorous constraints on the timing of crustal growth of the NCC. It is notable that we have just compiled the data having coupled zircon U-Pb age and Hf isotope analyses in the present study. At the same time, detrital/ inherited zircons with ages >2.7 Ga (age discordant <10%) and Hf isotope model ages out the scope of the Neoarchean are also mentioned.

4. Data sources

The basement of the NCC is mainly dominated by ~ 2.5 Ga rock series with minor Early- to Middle-Archean and Paleoproterozoic rocks. Hf and Nd-isotope studies show that minor EB crustal growth occurred in Early- to Middle-Archean and variable proportions of Paleoproterozoic crustal growth occurred in both the EB and WB and the TNCO. As this contribution concentrates on the Neoarchean (2.8—2.5 Ga) crustal growth of the NCC, pre-Neoarchean crustal growth is beyond of the scope of this study, and detailed information about the growth of pre-Neoarchean crust can be found in the relevant references (e.g., Jahn et al., 1987, 2008; Liu et al., 1992, 2007, 2008; Song et al., 1996; Wan et al., 2005, 2009a; Wu et al., 2005a,b, 2008a; Wilde et al., 2008; Zheng et al., 2004a; Nutman et al., 2009, 2011; Geng et al., 2010, 2011). In addition, some Nd-isotope data have also been recently published (e.g., Wan et al., 2005; Wu et al., 2005b; Chen et al., 2006a; Li et al., 2006, 2008; Liu et al., 2006b; Jahn et al., 2008; Wang et al., 2009).

Published Hf isotope data of each block are listed in Table 1. Data for the WB are mainly from Xia et al. (2006a,b, 2008, 2009), Dong et al. (2007, 2009), Li et al. (2007), Wan et al. (2009b), Yin et al. (2011); that of the EB from Zheng et al. (2004a,b), Yang et al. (2005, 2008), Luo et al. (2008); Du et al. (2010a); Jiang et al. (2010); Li et al. (2010); Wan et al. (2010a, 2011b); Wang et al. (2011); Zhang et al. (2011a,b); and that of the TNCO from Chen et al. (2006b); Xia et al. (2006c); Diwu et al. (2007, 2008, 2010, 2011); Guo et al. (2008); Liu et al. (2009b,c, 2011b,c,d); Xu et al. (2009); Zhou et al. (2009a,b, 2011); Huang et al. (2010); Jiang et al. (2010).

4.1. Western block 4.1.1. Khondalite Belt

Hf isotope data have only been reported from the Khondalite Belt and from the Zhaertai Group within the Yinshan block. The main features of the Hf isotope compositions are evaluated as follows.

Xia et al. (2006a, 2008) have carried out detrital zircon U-Pb and Hf and whole-rock Sr-Nd isotopic compositions of the khondalites from the Jining complex in order to trace the crustal growth of the WB. Detrital zircons were mainly derived from 1.9 Ga to 2.1 Ga Paleoproterozoic rocks. Sr-Nd-Hf isotopic data suggest that 65%—75% juvenile materials from the depleted mantle was accreted at 2.1 Ga with 25%—35% pre-existing ~2.6Ga continental crustal contamination. No ~2.7Ga crustal materials were found, but only one zircon has Hf model age of 2.71 Ga. The zircon age data are consistent with the new results of Li et al. (2011a).

In-situ U-Pb and Hf isotopic study for detrital zircons from the Wulashan khondalites shows that U-Pb ages have a wide range from 1.84 Ga to 2.32 Ga with some sporadic Late Archean ages and significant addition of juvenile materials took place at w 2.0 Ga. More importantly, the main crustal growth period was at ~2.6Ga with a shoulder at ~2.7Ga (Xia et al., 2006b). Therefore, the ~2.6Ga and ~2.7Ga crustal growths probably represent two discrete stages rather than a continuous process based on the following reasons: (1) the frequencies of ~2.6 Ga and ~2.7 Ga Hf model ages are different, with the former being much higher than the later. If they represent a continuous process they should have the same frequencies; and (2) in zircon age spectra, some zircon grains have ages of 2.5—2.6 Ga but no ages of >2.7 Ga (Xia et al., 2006b). It is noted that zircon age and Hf isotope data between different samples have some notable differences, some zircon grains give Hf model ages of >2.7 Ga whereas others do not. Thus, it is possible that the ~2.7 Ga Hf model ages may be underestimated.

Dong et al. (2009) and Wan et al. (2009b) reported zircon U-Pb ages and Hf isotope data for detrital zircons in the Daqingshan area of the Khondalite Belt and obtained results similar to other areas in the Khondalite Belt. Specially, the source of the detrital zircons was mainly derived from Paleoproterozoic rocks with abundant 2.56—2.51 Ga rocks, and Hf isotope data show that the crustal growth occurred in the Paleoproterozoic with some 2.6—2.5 Ga juvenile mantle-derived materials being accreted to crust involving minor Early- to Middle-Archean crustal materials.

U-Pb and Hf isotopic analyses of zircons have been carried out for the Helanshan complex by Dong and

(2011). Magmatic-type detrital zircons reveal two distinct age-

groups: 2.85-2.53 Ga and 2.2-2.0 Ga. Corresponding Hf isotope data indicate that 2.85-2.53 Ga zircons possess negative £Hf(t) values with depleted mantle model ages of 3.34-3.10 Ga, whereas nearly all 2.2-2.0 Ga zircons have positive eHf(t) values with depleted model ages of 2.45-2.15 Ga. Paleoproterozoic crustal growth was therefore far more important than that of Paleo-Mesoarchaean (Yin et al., 2011). Dong et al. (2007) also obtained the same result. Zircon Hf model ages of the nearby Paleoproterozoic Bayanwula gneissic granite have - 2.6 Ga age peak, consistent with other areas within the Khondalite Belt (Dong et al., 2007). However, Dan et al. (2011) gave an alternative explanation.

Xia et al. (2009) proposed that the Liiliang khondalites within the Louliang complex were deposited along the eastern margin of the WB, and were subsequently thrusted eastward during the collision between the EB and WB, so they are different from other supracrustal assemblage in the TNCO. Zircon U-Pb ages and Hf isotope data support this conclusion and show that the dominant provenance for detrital zircons of the khondalites were derived from 1.9 Ga to 2.1 Ga rocks with minor Archean rocks (one zircon with a Middle-Archean age and three zircon ages in the range of 2.5-2.6 Ga). Hf isotopic data indicate that -2.1 Ga is the main crustal growth period with some - 2.6 Ga crustal material involving in the Paleoproterozoic magmatic event. The data from the Lui liang khondalites is similar to that of the Jining khondalites (Fig. 3).

In summary, zircon U-Pb age and Hf isotope data of the Khondalite Belt suggest that the main crustal growth time is the Paleoproterozoic involving various degrees of - 2.6 Ga crustal material contamination. At the same time, sporadic - 2.7 Ga and Early- to Middle-Archean crustal materials are also locally found in the detrital zircons in some regions, which is confirmed by detrital zircon ages (Darby and Gehrels, 2006). A distinct difference between different areas of the Khondalite Belt is that they have various source materials, i.e., some areas are dominated by Paleoproterozoic crustal rocks with no Early Archean crustal compositions but others by Paleoproterozoic crustal rocks with minor Early Archean crustal materials. The amount of 2.5-2.6 Ga crustal materials in different areas has different proportions. The main crustal growth time took place in the Paleoproterozoic with some - 2.6 Ga and sporadic - 2.7 Ga and Early- to Middle-Archean crustal material (Fig. 3).

4.1.2. Ynshan block

In the Yinshan block, the published zircon ages and Nd-Hf isotopic compositions of the Zhaertai Group suggest that Archean basement rocks underlying this group have detrital zircon age population of -2500 Ma, and the Hf model ages have a -2.7 Ga peak with minor 3.8 Ga and 2.5 Ga crustal accretion (Li et al., 2007). Thus, the main crustal growth in the region most likely took place at - 2.7 Ga (Fig. 3).

Additionally, indirect evidence on crustal growth periods can be from Late Neoarchean high-Mg diorites. Jian et al. (2005) proposed that high-Mg diorites at Guyang, Inner Mongolia, in the Yinshan block have geochemical features similar to Archean sanukite with SHRIMP zircon U-Pb age of -2.55 Ga. The two-stage model has been widely used to explain the generation of sanukitoid magmas (e.g., Smithise and Champion, 2000; Wang et al., 2009). In the first stage, the mantle was metasomatised by fluids/melts derived from the subducted slab and then the previously metasomatised mantle melted to generate the sanukitoid magmas. Some sanukitoids in the Baltic Shield have Nd-isotope

Table 1 Zircon Hf isotope data from the basement and supracrustal rocks of the North China Craton.

Khondalite Belt

Locality Samples Zircon ages Hf isotope composition References

Jining. High-grade Al-rich gneisses More than 200 detrital zircon Hf model ages range from Xia et al., 2006a;

include a medium-grained grains show three age 2.08 Ga to 2.74 Ga with a peak at Xia et al., 2008;

sillimanite-garnet-feldspar populations of 2060, 1940 and 2.24—2.40 Ga, most samples Li et al., 2011a

gneiss, a sillimanite-garnet- 1890 Ma without ages formed by mixing of 65%—75%

feldspar gneiss, a sillimanite- >2500 Ma; metamorphic rims 2.1 Ga depleted mantle and

garnet gneiss. with an age of ~ 1811 Ma. 25%—35% -2.6 Ga crust.

Wulashan. Two garnet-bearing metapelitic Detrital zircons give U-Pb ages Significant addition of juvenile Xia et al., 2006b

gneisses, i.e., sillimanite- of 1.84-2.32 Ga with a single materials at — 2.0 Ga with

garnet-biotite gneiss and peak at ~2.0Ga. voluminous — 2.6 Ga ancient

meta-quartzite. crustal material remelting.

Helanshan. Six fine- to medium-grained Magmatic-type detrital zircons The main crustal growth events Yin et al., 2011

garnet-sillimanite-cordierite reveal two age populations, one were in the Paleoproterozoic

gneisses, a fine-grained garnet- in Archaean (2.85-2.53 Ga, with contamination of

bearing quartzite, two S-type minor) and the other in minor — 2.60 Ga and

granites. Paleoproterozoic (2.2-2.0 Ga, main). Paleo—Mesoarchaean (3.34—3.10 Ga) crustal components.

Bayan Ul-Helanshan. A gneissic granite and a garnet- Zircons from the gneissic granite TDM1 of Hf isotope for the Dong et al., 2007

mica two-feldspar gneiss. show core-mantle-rim structures with magmatic core and metamorphic mantle and rim yielding ages of 2323, 1923, 1856 Ma. Detrital zircons from garnet-mica two-feldspar gneiss have a weighted mean age of 1978 Ma and a few older ages (2469-2871 Ma). gneissic granite have a range of 2455—2655 Ma, half of which are in Paleoproterozoic and the other in —2.6 Ga. TDM1 of Hf isotope for garnet-mica two-feldspar gneiss have a wide range of 1999—3047 Ma, most of which are in the Paleoproterozoic.

Daqingshan. Two samples from Sanggan Four episodes of tectono-thermal Three episodes of juvenile, Wan et al., 2009b;

Group, five samples from events occurred in 2.6-2.5, depleted mantle-derived Dong et al., 2009

Wulashan Group and a quartzite 2.45-2.37, 2.3-2.0 and materials were accreted to the

from Meidaizhao Group. 1.95-1.85 Ga. crust, i.e., 2.60—2.50, 2.37 and 2.06 Ga involving subtle ancient crustal components.

Jiehekou Group in the Lüliang Three samples comprise a meta- Detrital zircon ages of the three Hf isotope compositions suggest Xia et al., 2009

complex (Jinzhouyu area). quartzose sandstone, a samples show a provenance that the main juvenile crustal

sillimanite-bearing biotite gneiss dominated by 1.9-2.1 Ga rocks growth event took place at

and a metamorphosed pebble- with minor 2.5-2.6 Ga crustal 2.1 Ga involving the remelting

bearing quartzose sandstone. materials. of — 2.6 Ga old crustal materials. (continued on next page)

Khondalite Belt

Locality

Samples

Zircon ages

Hf isotope composition

References

Yinshan block Zhaertai Group (Inner Mongolia).

Trans-North China Orogen Wanzi supracrustals within the Fuping complex (Taihangshan region).

Yejishan Group in the Luliang complex in Luliangshan.

Hutuo Group in the Wutai complex in Wutaishan.

Songshan Group in the Songshan region, Henan Province.

Four sandstones, one migmatitic granite and one basalt.

Four sillimanite-bearing gneissic samples.

Four samples consist of a grey black meta-siltstone, a pale red feldspar-quartz sandstone, a grey siltstone, and a feldspar-quartz sandstone. Ten samples include greywackes, arenites, sublitharenites and litharenites.

Quartzite.

Forty-seven zircon grains from four sandstones give ages ranging from 2527 Ma to 2403 Ma with an age peak at 2500 Ma. The granite was formed at 2564 Ma and experienced migmatization at 2480 Ma. The basalt was formed -1750 Ma with xenocrystic zircons being from 2536 Ma to 2134 Ma.

Inherited igneous zircon cores yield two age-groups at -2.10 Ga and -2.51 Ga with few ages scattering between 2.5 and 2.9 Ga.

Detrital zircons have a wide age range of 1.81-3.24 Ga with dominant Paleoproterozoic ages.

Detrital zircons have a wide age range with two peaks at - 2470 and -2150 Ma.

Ninety-nine analyses for detrital zircons yield four age-groups at — 3.40 Ga, 2.77-2.80 Ga, -2.50 Ga and 2.34 Ga. The -2.50 Ga zircon grains constitute -85% of the total grain population.

TDM1(Hf) of the four sandstone samples range from 2900 Ma to 2500 Ma, clustering at -2.7 Ga. Two highly negative initial eHf values have model ages of - 3800 Ma.

All ~2.51 Ga ages with positive initial sHf values of +1.4-+10.9, indicating an important crustal growth event at ~2.5 Ga with minor 2.8 Ga ancient crustal components. w 2.1 Ga zircons are featured by remelting of pre-existing old crustal materials with minor juvenile material contribution. Hf model ages have a main age peak at ~2.6 Ga with minor older crustal components.

Hf model ages have a large rang between 2.3 and 3.0 Ga with age-peaks at ~2.6Ga involving the remelting of >2.7 Ga older crustal materials. 2.77-2.80 Ga detrital zircons are minor and their Hf isotope data indicate they were derived from coeval depleted mantle; most of w 2.50 Ga detrital zircons have positive eHf values, suggesting that they derived from 2.5 -2.6 Ga depleted mantle involving remelting of some old crustal materials.

Li et al., 2GG7

Xia et al., 2GG6c

Liu et al., 2G11d

Zhang et al., 2GG6; Liu et al., 2G11c

Diwu et al., 2GG8

Taihua complex exposed in Yiyang area in Henan Province. Zhangjiakou region.

Chengde—Luanping and

Chicheng—Zhangjiakou areas in northern Hebei Province. Huai'an.

Two TTG gneisses.

A pyroxenite xenolith entrained in the tertiary Hannuoba alkali basalts; a tonalitic gneiss, a mafic granulite and an amphibolite from the basement of the Zhangjiakou region. Monzogranitic gneiss.

Four TTG gneisses and dioritic

gneisses.

Wutai complex in Shanxi Province.

A gneissic K-rich granitic pluton.

Sushui complex in the Zhongtiao mountains.

Three TTG gneiss samples.

Late Archean Taihua complex in Lushan region, Henan Province.

Two TTG gneisses and two amphibolites in the gneisses series of the Taihua complex.

Late Archean Taihua complex in Lushan region, Henan Province.

One dark-grey gneiss (TTG-like gneiss) and one light-grey gneiss (TTG gneiss).

The LA-ICPMS zircon U-Pb analyses give — 2.3 Ga formation ages.

They give various ages ranging from — 2.7 Ga through — 2.5Ga to — 1.8 Ga.

Hf model ages have a wide range of 2.57-3.01 Ga with a peak at -2.8 Ga.

Nd-Hf isotope data indicate that all of them were abstracted from depleted mantle at 2.7—2.8 Ga.

Diwu et al., 2007

Jiang et al., 2010

LA-ICP-MS zircon U-Pb dating reflects its crystallization age of -2510 Ma.

In-situ zircon ages show that they were formed at — 2.5 Ga.

The gneissic K-rich granitic pluton was emplaced at -2509 Ma.

SHRIMP zircon U-Pb dating indicate that they were emplaced during 2.53-2.56 Ga.

The TTG gneisses and amphibolites are dated at 2794-2752 Ma, some 2.9 and 3.1 Ga xenocrystaic zircons are found in the amphibolites. The TTG-like gneiss gives emplacement age of 2765 Ma and the TTG gneiss yields emplacement age of 2723 Ma.

Nd-Hf isotope data suggest that they were abstracted from depleted mantle at ca. 2.7 Ga. Zircon Hf isotope data show that they were derived from depleted mantle at 2.5—2.6 Ga. Almost all of the zircons have positive initial i-Hf values, suggesting that most of them were abstracted from depleted mantle at ca. 2.6 Ga involving the remelting of minor ancient crustal materials. Zircon Hf isotope data suggest that they were extracted from depleted mantle at — 2.6 Ga involving some older continental crustal materials. Both the TTG gneisses and amphibolites were extracted from depleted mantle at 2.7—2.8 Ga with reworking of some older crustal materials. Nd-Hf isotope gives model age range of 2.8—3.1 Ga. Considering that the most positive i-Hf values approach the coeval depleted mantle and the model ages are roughly equal to the formation ages of the gneisses, an important crustal accretion may happen at 2.7—2.8 Ga involving contamination of some ancient crustal materials.

Liu et al., 2011b

Liu et al., 2009b

Chen et al., 2006b

Guo et al., 2008

Diwu et al., 2010

Huang et al., 2010

(continued on next page)

Table 1 (continued)

Khondalite Belt

Locality Samples Zircon ages Hf isotope composition References

Taihua complex in Lushan area Two supracrustal rocks include a In-situ zircon dating indicate that Coupled zircon Hf-O isotope Liu et al., 2009c

in Henan Province. banded amphibolite and a they were formed during compositions of magmatic

gneissic amphibolite and two 2.83—2.85 Ga and experienced domains show that most of them

tonalites include a biotite tonalite at least two stages of were derived from 2995 Ma

and a hornblende tonalite. metamorphism at —2.8 Ga depleted mantle source with

and —2.7 Ga. some minor crustal

contamination.

Dengfeng complex in Junzhao Two TTG gneisses, an LA-ICPMS zircon U-Pb dating Zircon Hf isotope data show that Diwu et al., 2011

region. amphibolite and a metadiorite. shows that the Dengfeng 2.5-2.6 Ga is a major period of

complex was formed during crustal growth in the southern

2504—2547 Ma. NCC.

Dengfeng complex in the Two TTG gneisses. SHRIMP zircon U-Pb analyses Nd-Hf isotope data suggest that Zhou et al., 2009a

Songshan area. yield a crystallization age of they were derived from — 2.6 Ga

2600—2500 Ma. depleted mantle source.

Xutai and Lujiagou plutons One sample from Xutai pluton The crystallization age of Xutai The Xutai pluton has zircon Hf Zhou et al., 2011

exposed in the Songshan—Jian and one sample from Lujiagou pluton is 2509 ± 33 Ma and that isotope compositions similar to

area. pluton. of Lujiagou pluton is the coeval depleted mantle

2424 ± 24 Ma. Both of them values, suggesting that some

contain inherited zircons with crustal growth occurred

age of 2.77 Ga. at —2.5 Ga; whereas the

Lujiagou pluton has zircon Hf

isotope composition similar to

the Songshan TTG gneisses with

a range of 2802-2652 Ma.

The upper Taihua Group An amphibolite from the They were formed during Nd-Hf isotope data suggest that a Xu et al., 2009

(complex). Xiong'ershan terrane and 2.3—2.5 Ga and experienced magmatic episode with juvenile

a biotite gneiss from the metamorphism at 2.1 Ga. Some input at 2.3-2.5 Ga with some

Lantian—Xiaoqingling terrane. zircon grains have ages of older crustal component being

2505—2529 Ma. >3.1 Ga old.

Eastern block

Yixian—Fuxin greenstone belt in Three representative samples of Magmatic zircon ages of the All the magmatic zircons Wang et al., 2011

Liaoning Province. hornblende plagioclase gneisses Yixian—Fuxin greenstone belt give positive EHf values of

were carried out for age and indicate that they were formed +2.7—+8.3 with model ages

Lu-Hf isotope analyses. at 2534—2589 Ma. of 2.76-2.57 Ga. The youngest

model age is close to their

crystallization ages, suggesting

that they were derived from

2.5 Ga to 2.6 Ga depleted

mantle. Therefore, 2.5-2.6 Ga is

an important time of crustal growth in the western Liaoning terrane.

The intrusive rocks from eastern Hebei.

Taishan region in western Shandong Province.

Four samples include a diorite, two granodiorites, a K-feldspar granite, a granitic gneiss and a biotite-plagioclase gneiss. An amphibolite and a tonalitic gneiss from the basement in Taishan region.

The south and north Liaohe Group in the Jiao-Liao-Ji Belt.

Seven samples, i.e., a biotite schist, a staurolite mica schist, three fine-grained biotite gneisses, a felsic gneiss were conducted for zircon U-Pb dating and Hf isotope analyses.

Shuichang BIF in eastern Hebei Province.

A plagioclase-hornblende gneiss in Shuichang iron deposit.

Zunhua complex in eastern Hebei Province.

Two dykes include an olivine gabbro and a syenite.

Taishan-Xintai area, western Shandong Province.

Three samples of supracrustal rocks in Taishan association include a fine-grained hornblende-biotite gneiss, a fined-grained biotite gneiss and a mylonitized fine-grained biotite gneiss. Five Archean granitoids of TTG composition include a quartz diorite, two gneissic trondhjemites, a gneissic tonalité and a fine-grained granodiorite.

All the intrusive rocks have similar crystallization ages of 2515-2526 Ma.

The amphibolite was formed at 2570 ± 18 Ma, and tonalitic gneiss was formed at 2691 ±7 Ma.

Magmatic-type detrital zircons from both groups give the same results with two age populations at 2.0—2.2 Ga (major) and ~2.5 Ga (minor) plus minor >2.7 Ga ages.

Zircon cores yield a concordant age of 2547 ± 7 Ma, interpreted as the forming age of the protolith of the plagioclase-horblende gneiss.

The magmatic crystallization age of the olivine gabbro dyke and the syenite dyke are 2516 ±26 Ma and 2504 ±11 Ma, respectively. All the supracrustal and granitic rocks were formed during early Neoarchean (2.70-2.75 Ga).

Zircon Hf model ages show that the main age-peaks cluster at 2.7—2.8 Ga with minor older model ages.

Zircon Hf isotope composition indicates that both samples were derived from depleted mantle at -2.7 Ga.

Hf isotope data show that the zircons of the two age populations were abstracted from depleted during 2.7—2.8 Ga involving a significant addition of juvenile materials at 2.0-2.2 Ga.

Almost all the zircon £¡¡¡(0 values are negative with single-stage Hf model ages being from 2836 Ma to 3249 Ma, suggesting that the gneiss was mainly derived from >3.0 Ga ancient crustal materials with minor addition of ~2.8 Ga depleted mantle.

Their zircons have single-stage Hf model ages of ~2.7 Ga.

Most of magmatic zircons from supracrustal and granitoid rocks show highly positive i-Hf values approaching the values of the coeval depleted mantle, meaning that the continental crust was mainly formed during 2.70-2.80 Ga.

Yang et al., 2008; Wan et al., 2011c

Jiang et al., 2010

Luo et al., 2008

Zhang et al., 2011b

Li et al., 2010

Wan et al., 2010a, 2011b; Du et al., 2010a

Figure 2 Zircon 207Pb/206Pb ages vs. £Hf(t) diagram of the Archean plutonic rocks. Data sources are given in the text and in Table 1. The dashed gray line represents the 0.75eHf of the coeval depleted mantle (Belousova et al., 2010; Diwu et al., 2011).

characteristics similar to the coeval depleted mantle, whereas others have lower initial eNd(t) values (Kovalenko et al., 2005). The later is widely observed by various authors like Shirey and Hanson (1984) who first introduced the term sanukitoid to Archean Shield. The Nd-isotope data indicate that metasomatic enrichment of the mantle could not have occurred more than 100-200 Ma before melting. Accordingly, it is suggested that the

crustal growth occurred at -2.5 Ga or -2.7 Ga, but -2.7 Ga is more probably.

Thus, in terms of limited zircon Hf isotope data and the U-Pb ages of sanukitoid mentioned above, it is inferred that the main crustal-forming time of the Yinshan block occurred in - 2.7 Ga. At the same time, - 2.7 Ga crustal materials supplied local sedimentary sources for the khondalites in the Khondalite Belt (Fig. 3).

Figure 3 Zircon Hf model ages of the North China Craton. Data sources are given in the text. Data for the Yinshan block are from the detrital zircons of the Zhaertai Group. Data for the Khondalite Belt are from detrital zircons of khondalites in Jining, Wulashan, Helanshan and Daqingshan. In the Trans-North China Craton and eastern block subsections, light gray area represents data from detrital zircon from supracrustal rocks and the Liaohe Group; dark gray area represents data from zircons of TTG gneiss and late Neoarchean granitoids (Archean plutonic rocks).

4.2. Trans-North China Craton

Extensive zircon geochronology for basement rocks of the TNCO have contributed our understanding to the evolution of the NCC. The age data show that the main magmatic events in the TNCO occurred in ~2.5 Ga with subdominant Paleoproterozoic magmatic events. Minor ~2.7Ga basement components and zircon age population are also recognized in the TNCO. Specially, a medium-grained hornblende gneiss enclave within biotite orthogneiss collected from the Fuping complex yields a SHRIMP U-Pb zircon age of 2708 ± 8 Ma, which is considered to be the crystallization age of the tonalitic protolith (Guan et al., 2002); two samples of foliated grey biotite gneiss and grey granodioritic gneiss within the Hengshan complex are dated at 2701 ± 6 Ma and 2697 ± 1 Ma, respectively, and are interpreted as formation ages of the formation age of granitoid plutons (Kroner et al., 2005a,b). No rocks of similar ages have been documented in the Wutai complex, but some Wutai granitoid rocks contain a small number of zircons with ages of ~2.7 Ga (Wilde et al., 2004, 2005). In contrast to the middle segment of the TNCO, more ~2.7 Ga and even older basement components and zircon ages are recorded from the southern margin of the TNCO (Kroner et al., 1988; Gao et al., 2005a; Yang, 2008; Liu et al., 2009c). For example, TTG gneisses and amphibolites of the Taihua complex are dated at 2.7—2.8 Ga by Diwu et al. (2010) and Huang et al. (2010), and much older ages of ~2830 Ma are

reported by Liu et al. (2009a,b,c). Xeocrystic zircons with ages of 2.9 Ga and 3.1 Ga were also found in amphibolites from the Taihua complex (previously the lower Taihua Group, also named as the Dangzehe complex by Yang, 2008) by Diwu et al. (2010).

In addition to the basement plutonic rocks (including TTG gneisses, metadiorite, amphibolite and potassic granite), numerous SHRIMP zircon U-Pb ages have been also collected from detrital zircons in the supracrustal rocks. Main age-peaks occur in ~2.5 Ga and ~2.1 Ga in the zircon age spectra, but some much older ages are found in detrital zircons (Du et al., 2010b). For instance, the Gaofan Group possesses detrital zircon ages of ~2.7Ga and some older ~3.4Ga detrital zircons (Wan et al., 2010b). Detrital zircon ages as old as 2.7—2.8 Ga and ~3.9Ga are also reported from the Hutuo Group by Liu et al. (2011c), and detrital zircons with ages of ~2.8Ga and ~3.24Ga are documented in the Yejishan Group within the Liiliang complex by Liu et al. (2011d). Paleoproterozoic supracrustal rocks within the Taihua complex (previously called the upper Taihua Group) contain detrital zircons as old as 2873 and 2956 Ma (Diwu et al., 2010). Some detrital zircon grains with ages of 3.26—2.65 Ga were identified in quartzite within the Paleoproterozoic Songshan Group (Diwu et al., 2008).

Coupled U-Pb and Hf analyses have been conducted for the plutonic and supracrustal rocks and the results are discussed below.

UL-au^______________ui_■ I ■iiiwii _ . JL_,_

1600 2400 3200 4000 1600 2400 3200 4000

Age (Ma) A9« <Ma)

Figure 4 Age spectra for zircons from the basement of the North China Craton (after Wan et al., 2011a). A: All data for the North China Craton; B: Data for eastern block; C: Data for western block; D: Data for Trans-North China Orogen. MA = magmatic zircon; D & I = detrital and inherited zircon; ME = metamorphic zircon.

4.2.1. Plutonic rocks

The basement complex consists of two main lithological units of supracrustal and plutonic rocks. The plutonic rocks include TTG gneisses, metadiorites, amphibolites and potassic granites.

Liu et al. (2009b) carried out zircon U-Pb and Hf isotope analyses for the Huai'an terrane consisting mainly of TTG gneisses and dioritic gneisses in combination with whole-rock Nd-isotope compositions. The results suggested that the protoliths of these gneisses were emplaced at - 2.5 Ga and were extracted from depleted mantle at 2.5-2.6 Ga. Similar methods have been used to investigate the gneissic K-rich granitic pluton within the Wutai complex (Chen et al., 2006b). LA-ICPMS in-situ zircon U-Pb dating for a gneissic K-rich granite yields an age of 2509 ± 7.4 Ma and almost all of the zircon Hf data show positive initial £Hf(t) values, suggesting that they were melted from coeval depleted mantle involving minor ancient crustal components, which is supported by -2.7 Ga detrital/inherited zircon ages. The Precambrian Sushui complex of TTG composition in the Zhong-tiao mountain was taken for SHRIMP zircon U-Pb dating and Hf isotope analyses with formation age of 2536 ± 8 Ma and positive initial Hf isotope compositions, indicating that the magmas could be derived from the partial melting of 2.5-2.6 Ga juvenile crust material from the depleted mantle (Guo et al., 2008) (Fig. 2b). In short, these data imply that 2.5-2.6 Ga is an important time of crustal-formation of the central part of the NCC.

Neoarchean granitoid gneisses in the Chengde-Luanping and Chicheng-Zhangjiakou regions at the northern margin of the NCC are mainly composed of tonalitic, trondhjemitic, granodio-ritic and monzogranitic gneisses (TTGM). The dating results

suggest that they were formed at -2510 Ga and low eHf(t) values (—0.4 to +1.9) suggest that they were abstracted from -2.7 Ga depleted mantle, which is in good agreement with whole-rock Nd-isotope data (Liu et al., 2011b) (Fig. 2a). Four samples, including a pyroxenite xenolith in the tertiary Hannuoba alkali basalts, a tonalitic gneiss, a mafic granulite and an amphibolite from the basement of the Zhangjiakou area were investigated by Jiang et al. (2010) by applying zircon geochronology, geochemistry and isotope analyses. Zircon geochronology yields various ages of - 2.7 Ga, - 2.5 Ga and -1.8 Ga. Combined Nd-Hf isotope data suggest that all the target samples were extracted from - 2.7 Ga depleted mantle (Fig. 2e). Consequently, Jiang et al. (2010) presume that the - 2.7 Ga magmatism and crustal growth are probably much greater in extent than previously suggested.

Plutonic rocks along the southern margin of the NCC have also been extensively studied. The Taihua complex exposed in the Yiyang area of the western Henan Province was studied by Diwu et al. (2007). LA-ICPMS zircon dating indicates that the complex was formed at -2.3 Ga, and most of the zircon eHf(t) values exhibit negative values with minor low positive values. Two-stage zircon Hf model ages range from 2.57 to 3.01 with a main age peak at 2.8 Ga, probably indicating that they were derived from -2.8 Ga depleted mantle with 0.4-0.5 Ga crustal residence ages. The Taihua complex exposed in the Lushan region has been investigated by Liu et al. (2009c), Diwu et al. (2010), and Huang et al. (2010). The age data show that TTG gneisses and amphib-olites of the complex were emplaced between 2.7 Ga and 2.8 Ga with inherited zircon ages of 2.9 and 3.1 Ga. The combined zircon Hf isotope and whole-rock Nd-isotope data indicate that the

2.7—2.8 Ga tectono-thermal event represents an important period of crustal growth in the studied area involving the reworking of some ancient crustal materials (Fig. 2d). On the basis of integrated geochronology, geochemistry and isotope data, Huang et al. (2010) obtained the same conclusion as Diwu et al. (2010). But two differences are notable, the first is that the gray gneisses can be divided into TTG and TTG-like gneisses, the latter was formed slightly earlier than the former, and they each have different genesis models; the other is that these authors obtained more relic zircons (2.95—2.80 Ga) with negative eNd(t) and eHf(t) values. However, Liu et al. (2009c) suggested that tonalities and amphibolites of the Taihua complex in the Lushan region were formed at ~2.84Ga and subsequently underwent at least two episodes of metamorphism at ~2.78 and ~2.67Ga. Liu et al. (2009a,b,c) also found that the Hf and O isotopic features of the magmatic zircons are characterized by mostly positive eHf(t) values and mantle-like d18O values, suggesting that the main period of crustal growth is between 2.8 Ga and 2.9 Ga with minor contamination of ancient crustal materials (Fig. 2d). No ~ 1.85 Ga zircon metamorphic ages are documented as previously reported by Wan et al. (2006b). All the available data suggest that the geology of Lushan is more complex than previously suggested (Liu et al., 2009c).

The Dengfeng complex exposed in the Songshan region of Henan Province is an important part of the ancient crystalline basement in the southern segment of the NCC. In recent years, a large number of studies have been carried out (Wan et al., 2009c; Zhou et al., 2009a,b, 2011; Diwu et al., 2011). The plutonic rocks of the Dengfeng complex are composed of TTG gneisses, meta-diorite, amphibolite and granite. The dating results suggest that all of them were formed at 2.5—2.6 Ga with minor older inherited zircons except the Lujiakou pluton and the Shichen monzosyenite with formation ages of ~2.4 and ~ 1.78 Ga, respectively. The Hf data of 2.5—2.6 Ga magmatic zircons have positive eHf(t) values, where the highest values approach that of the contemporaneous depleted mantle. These results suggest that the rocks in the Dengfeng complex represent 2.5—2.6 Ga juvenile crust (Fig. 2c). In combination with other geochemical data, Diwu et al. (2011) and Zhou et al. (2009a,b) proposed that modern-style plate tectonics processes were probably initiated in the southern margin of the NCC during late Archean.

4.2.2. Supracrustal rocks and basin sediments Voluminous highly metamorphosed supracrustal rocks deposited upon the basement of the TNCO, some of which were considered to be originally formed at the foreland basins (Li and Kusky, 2007). Li and Kusky (2007) suggest that the Qinglong foreland basin extending N to NE up to 1600 km exists in the eastern side of the TNCO. This basin can be further divided into the northern Qinglong Group in the eastern Hebei Province, the middle Gaofan and Hutou Groups in the Wutaishan region and the Wanzi Group in the Taihangshan area, and the southern Songshan Group in the Songshan area. U-Th-Pb and Lu-Hf isotopic compositions of detrital zircons from the basin sediments can provide rigorous constraints on the crustal growth and evolution of the NCC (Krabbendam et al., 2008). As mentioned above, the main detrital zircon age populations concentrate at ~2.1 Ga and ~2.5Ga, consistent with ages of Archean TTG gneiss and Paleoproterozoic magmatic rocks. It is different from the age features of the khondalites in the WB characterized by main 2.1—2.0 Ga age-group with minor Archean zircon ages. There is also a marked source age difference between the southern margin and middle

sector basin sediments, implying that the southern margin is more complex than previously suggested. For instance, the Songshan Group lack —2.1 Ga detrital zircon ages, which widely occur in the Hutuo Wanzi Groups in the middle segment of the TNCO.

Xia et al. (2006c) firstly reported U-Pb age and Hf isotope data of detrital zircons from the Wanzi supracrustal rocks within the Fuping complex in order to constrain on the tectonic setting and evolution of the TNCO. The igneous zircon ages show two age-groups at —2.1 Ga and —2.5 Ga with some inherited zircons as old as —2.9 Ga. The —2.5 Ga ages have positive eHf(t) values of + 1.4 to +10.9, close to the values of the coeval depleted mantle, implying that 2.5-2.6 Ga is an important time of crustal growth. In addition, rare relict zircons show 2.8 Ga zircon Hf model ages. The —2.1 Ga zircons have both negative and positive initial Hf isotope ratios, interpreted as mixing of ancient crust materials with minor juvenile materials at — 2.1 Ga.

U-Pb and Hf isotope data of detrital zircons from the Hutou Group within the Wutai complex have been investigated by Liu et al. (2011c). The zircons have a wide age range from 1.88 Ga to 3.88 Ga with main Neoarchean to Paleoproterozoic ages, similar to the Wanzi Group. Most of the zircons exhibit positive eHf(t) values and have model age-peaks at — 2.6 Ga involving remelting of minor older crustal components. Similar researches are also carried out for detrital zircons from the Yejishan Group of the Luliang complex (Liu et al., 2011d). The detrital zircons have a wide range from — 1.8 Ga to — 3.24 Ga with two age-peaks at — 2.5 Ga and 2.1-2.2 Ga. Zircon Hf model ages show —2.6 Ga age-peaks with some ancient crustal materials.

All the above authors supposed that the older zircons or rocks are remnants of an older continental crust on which an Andean-type continental margin arc developed and then was incorporated into the TNCO during the collision between the WB and EB, and all of them may have formed in the same large foreland basin in the middle sector of the TNCO during the Lüliang movement.

Amphibolites from supracrustal rocks within the Dengfeng complex have been studied by Zhou et al. (2009a) and Diwu et al. (2011). Zircon dating results suggest that the protolith age of the amphibolite is 2547 Ma, and intergraded Nd-Hf isotope data indicate that they were extracted from depleted mantle during 2.5-2.6 Ga. U-Pb ages and Hf isotopes for detrital zircons from quartzite within the Paleoproterozoic Songshan Group are studied by Diwu et al. (2008). Ninety-nine detrital zircon ages have a large age range with several peaks clustering at —3.40, 2.77-2.80, —2.50 and — 2.34 Ga. Of these, — 2.50 Ga ages constitute about 85% of the total grain population and high and positive eHf(t) values are close to the ratios of coeval depleted mantle, implying that major growth of juvenile crust took place at — 2.50 Ga involving minor reworking of ancient crust. Furthermore, 2.77-2.80 Ga zircons make up a small proportion of the total zircon age population and have high eHf(t) values approaching that of coeval depleted mantle, implying that minor —2.8 Ga crustal growth also occurred.

Many studies suggest that the traditional Taihua Group can be further divided into the early Neoarchean (2.7-2.8 Ga) Dangzehe complex (previously known as the lower Taihua Subgroup) and the Paleoproterozoic Taihua complex (previously known as the upper Taihua Subgroup) (Yang, 2008; Diwu et al., 2010). The Paleoproterozoic upper Taihua Group (supracrustal rocks) consists of graphite-bearing gneisses, biotite gneisses, marbles, banded iron formations (BIF), amphibolites and quartzites. Coupled in-situ U-Pb dating and Hf isotope analysis of zircons from a bio-tite gneiss (from the Lantian-Xiaoqinling terrane) and an

amphibolite (from the Xiong'ershan terrane) suggest that the upper Taihua Group formed in the Paleoproterozoic (2.3-2.5 Ga). Nd-Hf isotope data indicate that 2.3-2.5 Ga magmas were derived from the depleted mantle source with some assimilation of ancient crustal material as old as 3.1-3.2 Ga (Xu et al., 2009). Xu et al. (2009) have proposed that the Taihua Group underwent strong metamorphism and deformation, and the terrains of Taihua Group were not formed by the collision between the EB and WB of the NCC. The Taihua Group may now represent an integral part of the Qinling Orogen terranes rather than simply being the southern extension of the Central Zone of the NCC.

In short, the obtained zircon U-Pb ages and Hf isotope compositions of the TNCO basement rocks suggest that some areas like Huai'an, Wutai, Dengfeng and Zhongtiaoshan are characterized by dominant 2.5-2.6 Ga crustal growth and other areas such as Lushan, Zhangjiakou, and northern Hebei Province are characterized by the main 2.7-2.8 Ga crustal growth. The southern margin of the TNCO is more complex than previously as evidenced by the presence of more 2.7 Ga and even older rocks and zircon ages (Fig. 3). Geochemical features also show marked differences as discussed below.

4.3. Eastern block

The EB has a long research history and is famous for the occurrence of Early Archean rocks (e.g., Liu et al., 1992). Except for >3800 Ma continental crust remnants, some rocks with ages ranging from 3600 Ma to 2800 Ma include ultramafic, mafic, and felsic volcanic rocks and pre-tectonic gneisses. About 80% of the Precambrian basement is composed of TTG gneisses, charnockites, granites, amphibolites, mafic granulites with ages of 2600-2500 Ma. The Paleoproterozoic Jiao-Liao-Ji Belt is located in the eastern part of the EB and divides the EB into the north Longgang block and the south Nangrim block (Luo et al., 2008; Li et al., 2011b; Zhao et al., 2011). The belt comprises metamorphosed sedimentary and volcanic successions metamorphosed to greenschist and amphibo-lite facies grade and voluminous granitic and mafic rocks. The metamorphic rock series includes the Jingshan and Fenzishan Groups in eastern Shandong, the south and north Liaohe Groups in eastern Liaoning, the Ji'an and Laoling Groups in southern Jilin, and possibly the Macheonyeong Group in North Korea. Strati-graphically, the Fenzishan Group is well correlated with the north Liaohe and Laoling Groups, and the Jingshan Group is well correlated with the south Liaohe and Ji'an Groups, representing the northern and southern belt of the Jiao-Liao-Ji Belt, respectively (Luo et al., 2008). The Liaohe Group occurs associated with voluminous Paleoproterozoic granitoids and mafic intrusions. Mafic intrusions consist of dolerites and gabbros, most of which experienced greenschist to amphibolites facies metamorphism. The granitoids, also called the Liaoji granitoids, comprise pre-tectonic A-type monzongranitic gneisses and post-tectonic undeformed porphyritic monzogranites, granites and alkali syenites. Zircon SHRIMP dating has been carried out for the granitoids by Lu et al. (2004) and Li and Zhao (2007). Although numerous structural, geochemical and geochronological investigations have been undertaken on the Jiao-Liao-Ji Belt (Faure et al., 2004; Li et al.,

2005, 2006, 2007, 2010, 2011b; Lu et al., 2006; Luo et al., 2004,

2006, 2008; Zhou et al., 2008; Tam et al., 2011a,b; Zhao et al., 2011), yet no consensus has been reached on the tectonic nature of the Jiao-Liao-Ji Belt. Different models, such as rifting, arc-continent/continent-continent collision, rifting-and-collision, have

been proposed. Luo et al. (2008) initially carried out U-Pb and Hf isotopic analysis of detrital zircons from the south and north Liaohe Groups, and many investigations have also been undertaken on the basement rocks. The most significant difference between the EB and WB and the TNCO is that the wide occurence of >3.8 Ga zircons and Early Archean crustal materials. Numerous geochro-nological and Nd-Hf isotopic data have been reported to elucidate the early stage evolution of the eastern NCC (Wu et al., 2005a, 2008a; Wilde et al., 2008; Zhang et al., 2011a). Crustal growth with age-peaks at — 3.4, — 3.6 and — 3.9 Ga are documented based on geochronology and Nd-Hf isotope data, no detailed information is given in this contribution and the readers can refer to the following papers (Wu et al., 2005a,b, 2008b; Wilde et al., 2008; Jahn et al., 2008; Wan et al., 2005, 2009a; Zheng et al., 2004a; Nutman et al., 2009, 2011; Geng et al., 2010, 2011; Zhang et al., 2011a).

4.3.1. North and south Liaohe Groups

Numerous detrital zircons extracted from the south and north Liaohe Groups have been used for U-Pb age and Hf isotope composition determination, in combination with previous Nd-isotope data and geochronology, Luo et al. (2008) gave some important conclusions on the crustal growth history of the eastern margin of the EB. Detrital zircons show two age-groups at —2.50 Ga (minor) and —2.10 Ga (major), consistent with the ages of the basement gneisses and Liaoji granitoids. Hf isotope compositions of — 2.5 Ga zircons suggest that the main mantle extraction event in the EB occurred in — 2.8 Ga involving the remelting of minor ancient crustal materials, those of the — 2.10 Ga detrital zircons suggest that the precursor magmas were mostly abstracted from depleted mantle at — 2.7 Ga with minor addition of —2.10 Ga mantle-derived materials (Fig. 3).

The crustal growth period of the EB revealed by the detrital zircons from the south and north Liaohe Groups is distinct from the results of detrital zircons from both khondalites in the WB and supracrustal rocks/basin sediments in the TNCO. The supracrustal rocks/basin sediments in the TNCO show that major crustal growth at 2.5—2.6 Ga with minor crustal growth at >2.8 Ga and in the Paleo-proterozoic, detrital zircons from Khondalite Belt exhibit the main crustal growth in the Paleoproterozoic involving some — 2.6 Ga and minor early Archean crustal accretion.

4.3.2. Basement rocks

Extensive studies have been undertaken for the western Shandong Province in recent years by using methods of zircon dating, geochemistry and Nd-Hf isotope analyses (Du et al., 2010a; Wan et al., 2010a, 2011b). The age data suggest that the basement rocks consisting of TTG and supracrustal assemblages were formed in the Neoarchean (2.75—2.58 Ga) and were intruded by voluminous Late Archean quartz diorite, monzodiorite and granodiorite. Wan et al. (2011b) suggested that the western Shandong Province is a greenstone-granite terrain and is characterized by both — 2.7 Ga and —2.5 Ga magmatic events, and that the Neoarchean basement can be divided into three belts: a late Neoarchean (2525—2490 Ma) crustally-derived granite belt (Belt A) in the northeast; an early Neoarchean (2.75—2.60 Ga) belt of TTG and supracrustal rocks in the central (Belt B); and a late Neoarchean (2550—2500 Ma) belt of juvenile rocks in the southwest southwestern (Belt C). Hf isotope data indicate that the widely distributed crustally-derived — 2.5 Ga granites and 2.75—2.70 Ga supracrustal and TTG rocks were extracted from the depleted mantle at 2.7—2.75 Ga, and Late Neoarchean (2550—2500 Ma) juvenile rocks are also widely occurred. Thus, both 2.75—2.70 Ga and 2.55—2.50 Ga crust-forming events are widely developed in the western Shandong

Province, and the former may be much more widespread than the latter (Fig. 2g). Wan et al. (2011b) believed that the largest difference between the NCC and the other cratons in the world is not the weak development of tectono-thermal events in — 2.7 Ga, but the strong overprinting of — 2.5 Ga tectono-thermal events in the NCC. Jiang et al. (2010) also conducted combined U-Pb and Lu-Hf isotope analyses of zircons separated from an amphibolite and a tonalitic gneiss from the basement of the western Shandong Province in the Taishan region. The results suggest that the amphibolite and the tonalitic gneiss were formed at 2570 ± 18 Ma and 2691 ± 7 Ma, respectively, and both were derived from depleted mantle at — 2.7 Ga. The 2.8-2.7 Ga crustal accretion is also confirmed by Polat et al. (2006) in the Taishan region.

The Yixian-Fuxin greenstone belt is located along the northern termination of the eastern NCC. In terms of geochemistry, metavolcanic rocks in the greenstone belt can be grouped into four groups: normal-mid-ocean ridge basalts (N-MORBs), boninite-like rocks, adakite-like rocks and high magnesium andesites (HMAs), suggesting that they formed in an active continental margin setting related to oceanic slab subduction, similar to the southern margin of the NCC (Diwu et al., 2011; Zhou et al., 2011). Magmatic zircons suggest that the meta-volcanic rocks were emplaced at 2534-2589 Ma and have highly positive £Hf(t) values approaching to the coeval depleted mantle values. These data indicate that 2.5-2.6 Ga is an important episode of crustal growth in the western Liaoning metamorphic terrane (Wang et al., 2011) (Fig. 2f).

In contrast to the western Liaoning Province, the eastern Hebei region provides a different scenario (Yang et al., 2008; Li et al., 2010; Zhang et al., 2011b). Here, a rare coeval mafic-ultramafic and syenitic dykes intruding the 3.8-2.55 Ga Caozhuang complex have been dated by in-situ zircon U-Pb and Hf isotope analyses and the results suggest that they crystallized between 2504 Ma and 2516 Ma and were derived from depleted mantle at — 2.7 Ga. In combination with Sr-Nd isotopic and whole-rock geochemical data, these authors thought that these intrusions derived from an enriched mantle which was metasomatised by fluids/melt from a subducted slab and represent the latest stage of Archean magma activity (Li et al., 2010). Thus, —2.7 Ga is an important crustal growth period for the eastern Hebei region. SIMS U-Pb dating and in-situ Lu-Hf analysis of zircons from plagioclase-hornblende gneiss associated with the Shuichang BIF in the eastern Hebei Province have been made by Zhang et al. (2011b). The results indicate that the gneiss formed at — 2547 Ma, but almost all the £Hf(t) values are negative with single-stage Hf model ages being 2836-3249 Ma. This suggests that the gneiss was mainly derived from >3.0 Ga ancient crust with minor addition of — 2.8 Ga depleted mantle. Yang et al. (2008) also carried out LA-ICPMS and Lu-Hf isotopic analysis of zircons from Late Archean hornblenditc, tonalitc, dioritic, granodioritc and granitc plutons in the eastern Hebei Province. Magmatic zircons record emplacement age of 2526-2515 Ma and corresponding Hf isotopic data suggest that these rocks originated from partial melting of a juvenile lower crust at shallow crustal depths. Hf model ages indicate that they were derived from depleted mantle at 2.7-2.8 Ga with minor components of remelted ancient crustal materials.

Yang et al. (2005) also conducted zircon U-Pb and Hf isotope analyses of gneiss which hosts Paleoproterozoic Miyun rapakivi granite in Beijing. The results suggest that the gneiss was formed at —2521 Ma and derived from depleted mantle at 2.5-2.6 Ga (Fig. 2f). This conclusion is further confirmed by Ren et al. (2011).

Until now, no zircon Hf isotopic data have been reported for the Jiaodong Terrane in eastern Shandong Province. However, Jahn et al. (2008) conducted an intergrated study of zircon geochronology, bulk-rock elemental and Nd-isotope geochemistry on gneisses and granodiorites from the Jiaodong Terrane, in combination with a previous study by Tang et al. (2007), found that except for one TTG gneiss with age of — 2.9 Ga, the others yield ages of 2.71-2.73 Ga. Jahn et al. (2008) proposed that the most significant crust-forming episode in the Jiaodong Terrane is 2.71-2.73 Ga, similar to the western Shandong Province terrane.

A potential region of 2.7-2.8 Ga crustal growth could be the Houqiu area in the southeastern margin of the NCC. Basement rocks and detrital zircons with ages of 2.75-2.7 Ga are identified (Wan et al., 2010c), although are not confirmed by the Hf isotope data. Zircon xenocrysts from early Fuxian and Mengyin dia-moniferous kimberlites in the EB also show 2.7-2.8 Ga crustal accretion (Zheng et al., 2009). U-Pb geochronology and Hf isotopes of zircons separated from granulite xenoliths in Phaner-ozoic magmatic rocks and inherited xenocrysts from the associated lower crust rocks in the eastern domains of the NCC, also suggest that the main crustal growth occurred at — 2.7 Ga, although involving significant contribution of — 2.5 Ga juvenile materials. Recently, Geng et al. (2010, 2011) suggested that major crustal accretion of the EB and TNCO took place at 2.7 Ga and essential cratonization of the NCC took place at the end of Archean related to mantle plume activity.

In summary, the crustal growth period in the EB is complex. The main crustal growth period in eastern and western Shandong Province, and eastern Hebei Province occurred in — 2.7 Ga, whereas that of the western Liaoning Province and Miyun in Beijing happened at 2.5-2.6 Ga. The crustal accretion at —2.7 Ga may be an underestimate due to the extensive overprint of — 2.5 Ga tectonthermal events or insufficient data (Fig. 3).

4.4. Detrital zircon from modern river sediments

One of the best ways to elucidate crustal growth and terrane evolution history is to determine U-Pb age and Lu-Hf isotopic composition of detrital zircons from modern river sediments (Rion et al., 2004; Iizuka et al., 2010; Safonova et al., 2010). Four hundred and seventy-nine concordant detrital zircons in three sand samples from the Yellow River and two sand samples from the Yongding and Luan Rivers were determined by Yang et al. (2009). Several age-peaks occur in the zircon age spectra with one peak at 2.2-2.6 Ga, and one of the dominant groups of Hf crust model ages occur between 2.4 Ga and 2.9 Ga with a peak at 2.7-2.8 Ga. The 2.7-2.8 Ga age-peak in all the river sand samples agrees well with the coeval major peak for global crustal growth.

4.5. Detrital zircon from sedimentary cover rocks

Following the Lüuliang movement at — 1.8 Ga, the NCC was subjected to an extensional regime and voluminous thick-layered clastic rocks and carbonates were deposited in the margins or interior of the craton (Lu et al., 2008). The Meso- to Neo-proterozoic sedimentary succession can be divided into the Changcheng, Jixian and Qingbaikou Groups. U-Pb geochronology and Hf isotopic compositions for detrital zircons from the Meso-to Neoproterozoic cover succession of the NCC in the Ming Tombs area in Beijing have been measured by Wan et al. (2003, 2011a). Detrital zircon age spectra agree well with that of early

Precambrian basement of the NCC, both display age-peaks at - 2.5 Ga and - 1.85 Ga. While the age spectra has a notable change through different groups, the lower Changcheng Group is predominated by detrital zircons of late Neoarchean age, and the overlying Jixian and Qinbaikou Groups are dominated by late Paleoproterozoic zircons. More importantly, the - 2.5 Ga detrital zircons have various initial Hf isotopic values and Hf model ages of 2.7-2.8 Ga (Wan et al., 2011a; Ren et al., 2011).

4.6. Zircon in Precambrian lower crustal rocks

Recently, Zhang et al. (2011a) have made a comprehensive review of U-Pb geochronology and Hf isotopes of zircons collected from granulite xenoliths entrained in Phanerozoic magmatic rocks and zircons from inherited xenocrysts from associated lower crust rocks from various regions of the NCC, most of which concentrates on the EB except some granulite xenoliths in the Cenozoic Hannuoba basalts on the TNCO. These data provide important insights into understanding the growth and evolution of the lower crust and suggest that several episodic stages of growth of Precambrian lower crust beneath the NCC. These authors proposed that the oldest lower crust was indeed formed in the Eo-Archean with ages as old as 4.0-4.1 Ga. In addition to an important crustal growth period during 2.8-3.0 Ga and the Paleoproterozoic reworking of the Archean lower crust with some addition of juvenile materials, The Hf TDM ages show a main age peak at - 2.7 Ga, consistent with the data of xenocrystic zircons from both the Fuxian and Mengyin kimberlites (Zheng et al., 2009). These results suggest that 2.7-2.8 Ga is an important time of crustal accretion for the EB, corresponding to a major episode of global crustal-formation. It is interesting to note that the - 2.5 Ga tectono-thermal event involved both the remelting of pre-existing old crustal materials and input of juvenile materials, probably in association with mantle-derived magma underplating in mantle plume setting (Geng et al., 2010). This thermal event marks cratonization of the EB of the NCC. Thus, with respect to lower crustal evolution, both 2.7-2.8 Ga and 2.5-2.6 Ga crustal growth events occurred in the EB. The 2.7-2.8 Ga thermal event may be more widely distributed than that presently exposed, which may be due to the strong resetting and destruction of 2.5-2.6 Ga thermal event or insufficient data as suggested by Diwu et al. (2010); Jiang et al. (2010) and Wan et al. (2011a,b,c).

4.7. Zircon from Neoarchean syenogranites

At the end of the Neoarchean, voluminous syenogranites and K-rich granites were emplace in the NCC (e.g., Grant et al., 2009; Zhang et al., 2011c; Wan et al., 2011c). Such rocks are widely distributed in the EB including in the regions of Anshan-Benxi, Qin-huangdao, western Shandong, northern Liaoning, southern Jilin and northern Hebei, in the southern margin of the TNCO of central Henan and in the northern segment of the TNCO of the Huai'an area. Wan et al. (2011c) reviewed the zircon ages and geochemistry of these late Neoarchean syenogranites, and found that they were formed between 2.53 Ga and 2.50 Ga and generated by melting of continental crust with different mean crustal residence ages. Most of the -2.5 Ga granites including syenogranites have whole-rock Nd and zircon Hf model ages of 2.7-2.8 Ga, indicating an important time of crustal growth of the NCC. The zircon Hf data is also consistent with the results ofLietal. (2010)andZhangetal. (2011c) for the areas of eastern Hebei and Huai'an.

5. Discussion

5.1. Mantle extraction ages in the NCC

From the zircon Hf isotopic data described above (Figs. 2 and 3), there are some significant differences in crustal-formation ages between different divisions of the NCC. Combined with previous zircon U-Pb age and Hf isotope and whole-rock Nd-isotope data, some key points are obtained as follows. The EB is characterized by crustal growth episodes at -3.4, -3.6 and -3.9 Ga. The main crustal growth time in the Neoarchean is at 2.7-2.8 Ga in the eastern and western Shandong Province, eastern Hebei Province, with local crustal-formation at 2.5-2.6 Ga in western Liaoning Province and at Miyun near Beijing. The main crustal growth time in the Yinshan block of the WB occurred mainly in - 2.7 Ga, as indicated by detrital zircon Hf isotope compositions from the Zhaertai Group. Detrital zircon Hf model ages of the Khondalite Belt within the WB are very complex, the main feature is that they are mainly characterized by Paleoproterozoic crustal growth involving some - 2.6 Ga crustal materials and minor - 2.7 Ga, Early- and Middle-Archean and even older crustal compositions, in good agreement with the ages of detrital zircon from upper Proterozoic to Ordovician strata from the Zhuozi Shan in north-central China (Darby and Gehrels, 2006). The TNCO's crustal growth has a wide age range from 2.5 Ga to 2.9 Ga but marked differences exist in different localities. The Wutai, Huai'an, Dengfeng and Zhongtiaoshan complexes display 2.5-2.6 Ga crustal growth, while the basement in the Zhangjia-kou, Lushan and northern Hebei regions is characterized by 2.7-2.8 Ga crustal growth. The supracrustal rocks/basin sediments within the Luliang, Fuping and Wutai complexes are also characterized by 2.5-2.6 Ga zircon Hf model age-peaks involving minor 2.7-2.8 Ga and even older crustal materials. It is notable that the southern margin of the TNCO is featured by a greater proportion of 2.7-2.8 Ga and even older basement rocks and zircon ages and lacks evidence of - 1.85 Ga metamorphism in the Dengfeng complex, indicating that its evolution is more complex than previously considered.

In summary, the time of NCC's crustal growth is more complex involving both 2.7-2.8 Ga and 2.5-2.6 Ga. The 2.7-2.8 Ga magmatic events and crustal growth are more widely distributed than previously thought, which is confirmed by zircon Hf isotope data of modern river sediments, overlying sedimentary cover, Precambrian lower crustal rocks and Neoarchean syenogranites. Crustal growth and magmatism at 2.7-2.8 Ga may be underestimated due to the overprint of strong 2.5-2.6 Ga thermal tectonism, poor exposure and insufficient data.

It should be noted that the tectonic setting of - 2.5 Ga mag-matism and crustal growth is hotly controversial in that it considered to be the result of mantle plume activity or arc mag-matism, or both (Chen, 2007; Liu et al., 2007; Yang et al., 2008; Grant et al., 2009; Zhao, 2009; Geng et al., 2010, 2011; Wang et al., 2011).

5.2. Constraints on evolution and tectonic division of the NCC

Regarding the evolution and tectonic division of the Precambrian basement of the NCC, researchers have different opinions. Some suggest that the NCC can be tectonically divided into three parts, the EB (Yanliao block), the WB consisting of the Ordos and

Yinshan blocks, and the TNCO. There is controversy over the timing and tectonic process of amalgamation of the two blocks. One proposal is eastward-directed subduction of an old ocean, with final collision of the two blocks at — 1.85Ga; another is westward-directed subduction with final collision between the two blocks at —2.5 Ga. In recent time, a two-stage subduction model involving different Paleoproterozoic ages has been suggested (e.g., Wang et al., 2010b). In contrast, Zhai et al. (2000, 2010) proposed that the NCC can be divided into six micro-blocks; Ji'ning, Qianhuai, Fuping, Xuchang, Jiaoliao and Alashan blocks. They suggested that Precambrian crustal growth and stabilization of the NCC can be related to four major geological events: (1) a major phase of continental growth for the NCC at 2.7—2.9 Ga, which is in accordance other cratons worldwide; (2) the amalgamation of the micro-blocks and formation of the NCC were completed by —2.5 Ga, with a tectonic constitution defined by greenstone belts and high-grade metamorphic regions; (3) Paleoproterozoic rifting-subduction-accretion-collision tectonics and subsequent high-grade granulite-facies metamorphism and granitoid magma-tism at 1950—1830 Ma, suggesting that the NCC is an important part of the Columbia supercontinent; (4) the major subsequent Paleoproterozoic extension is considered to be plume-related, which finally resulted in the break-up of the NCC from the Columbia supercontinent at —1.8 Ga. However, Geng et al. (2010, 2011) suggested that the widely distributed magmatism at — 2.5 Ga was likely related to the mantle plume activity that caused partial melting and reworking of — 2.7 Ga crustal materials, and that essential cratonization of the NCC took place at — 2.5 Ga.

One of the major reasons resulted in the difference in understanding of the evolution and tectonic subdivision of the NCC is mainly due to the different interpretations on the zircon ages. There is a marked zircon age difference between the EB and WB and the TNCO. Recently, Wan et al. (2011a) have compiled a total of 7586 zircon ages from the entire NCC that comprise 3905 magmatic, 1511 metamorphic and 2170 detrital zircons (Fig. 4). Although there is an uneven geographic distribution of the data, some notable features are evident. The entire NCC is characterized by —2.5 Ga and — 1.8Ga tectonthermal events. Firstly, a series of rocks and zircons dated at >2.8 Ga are documented in the EB, i.e., in the Anshan region of Liaoning Province, Caoz-huang region of eastern Hebei Province, and Xinyang region of Henan Province. The — 2.8 Ga TTGs and supracrustal rocks are distributed in the Lushan region of central Henan Province. However, >2.8 Ga inherited and detrital zircons are widely discovered in the TNCO, e.g., the Wutai, Fuping, Jiaozuo and Dengfeng areas, and in the EB, e.g., Huoqiu, western and eastern Shandong Province. Secondly, — 2.7 Ga old rocks are identified in eastern and western Shandong Province and other areas of Huo-qiu, Zhangjiakou, Fuping, Hengshan, Lushan and Guyang, and detrital and inherited zircons of this age occur over almost the whole NCC. Thirdly, the strongest tectono-thermal event for the NCC occurred in —2.5 Ga, which is different from other worldwide cratons with — 2.7 Ga being predominant. There is controversy over the —2.5 Ga age involving juvenile crustal accretion or reworking of ancient crust or both. Finally, middle Paleoproter-ozoic 2.3—2.0 Ga rocks and inherited/detrital zircons are widely reported in the whole NCC, but from the statistical diagrams, the proportion of 2.3—2.0 Ga zircons in the WB is much higher than those in the EB and TNCO (Fig. 4). It is also supported by ages of detrital zircons from the supracrustal rocks. For instance, the majority of detrital zircons from the Khondalite Belt are

characterized by 2.3—2.0 Ga ages with a few yielding Archean ages, while detrital zircons from supracrustal rocks within the TNCO exhibit both —2.1 Ga and —2.5 Ga age-peaks.

Therefore, there is a marked difference in zircon age spectra between the EB, WB and the TNCO. It is reasonable to divide into the NCC into three main parts. The EB is characterized by ancient crustal relicts as old as 3.8 Ga and wide occurrence of 2.7—2.8 Ga magmatism with minor — 2.1 Ga and —1.85 Ga magmatism. The WB is characterized by strong —1.95 Ga, 2.1—2.0 Ga and —2.5 Ga mag-matism with minor ancient crustal materials as revealed by detrital zircons. The TNCO is characterized by main —2.5 Ga magmatism and some 2.3—2.1 Ga magmatism and widespread —1.8 Ga meta-morphism. However, there is a notable age difference between the middle and northern parts and southern margin of the TNCO. The southern margin is featured by widespread occurence of 2.7—2.8 Ga and even older rocks. and detrital/inherited zircons Conversely, detrital zircons of quartzite in the Paleoproterozoic Songshan Group lack — 2.1 Ga ages, as documented widely in the Wanzi, Hutou and Yejishan Groups in the central part of the TNCO.

Zircon Hf isotope data provide another constraint on the evolution of the NCC. The strongest magmatic event in the NCC took place at — 2.5 Ga, and many geologists consider that the main crustal-formation occurred at 2.5—2.6 Ga, probably in relation to mantle plume activity (e.g., Geng et al., 2010). While zircon Hf isotope data exhibit some notable differences between different parts of the NCC as mentioned above.

The combined zircon U-Pb ages and Hf isotope compositions can provide some constraints on the evolution and tectonic division of the NCC. Zhao et al. (2007) proposed that the TNCO was an Andean-type magmatic arc along the western margin of the EB and separated from the WB by a major ocean, with subduction of the oceanic lithosphere beneath the western margin of the EB. These authors suggested that the TNCO is a — 700 Ma long-lived accre-tionary magmatic arc and the closure of the ocean between the EB and WB at 1880—1820 Ma led to continent-arc-continent collision. At the same time they also proposed that Neoarchean evolution of eastern part of the NCC was related to mantle plume activity (Zhao, 2009). This model can reasonably explain the sporadic occurrence of —2.7 Ga and even older inherited/detrital zircons in the TNCO and the difference between the ages of detrital zircons in the Khondalite Belt and supracrustal rocks in the TNCO. The U-Pb and Hf isotope data of detrital zircons from basin sediments lend support to collision between the EB and WB during the Paleoproterozoic, rather than the Archean. However, some geologists propose a two-stage subduction model involving two collisional events, with the earlier one leading to the amalgamation of the Fuping and the eastern (Yanliao) blocks at about 2.1 Ga, and the younger one leading to final collision and suturing of the western and eastern blocks at 1.9—1.8 Ga. The main evidence supporting the two-stage subduction model is the —2.3 Ga mafic-ultramafic intrusion with positive eNd(t) values and nearly the same Nd model ages (ranging from 2643 Ma to 2200 Ma with the majority between 2350 Ma and 2200 Ma) (Liu et al., 2002; Wang et al., 2010a,b). The compiled Hf isotope data in this study are probably more supportive of the two-stage model because a weak — 2.4 Ga Hf model age peak of detrital zircons from supracrustal rocks/basin sediments probably implying the addition of —2.3 Ga depleted mantle material mixed with some older crustal materials, similar to the Nd-isotope data. However, because Hf isotope data is sparse and no corresponding Hf isotope analyses have been carried out for the mafic-ultramafic rocks, this view is inconclusive and more data are needed to confirm it or not.

However, Xu et al. (2009) have proposed that the rocks in the Taihua complex (upper Taihua Group) did not experience -1.85 Ga metamorphism and the terranes that make up the Taihua Group (complex) are not the southern extension of the Central zone of the NCC. In fact, in many aspects the southern margin of the TNCO is not the same as the middle and northern parts of the TNCO. For example, 2.7-2.8 Ga and even older rocks are more widely distributed along the southern margin (Gao et al., 2005a; Liu et al., 2009b; Diwu et al., 2010), the Dengfeng complex has no evidence of -1.85 Ga metamorphism and detrital zircons from quartzite within the Songshan Group lack 2.1-2.0 Ga ages. In addition, the geochemistry of volcanic rocks of the Angou Group along the southern margin suggests that the Angou Group formed in a continental rift setting, rather than in a magmatic arc setting as previously suggested (Gao et al., 2005b). Wan et al. (2010a,b,c) consider that there may be a Paleoproterozoic Southern North China Craton Orogen (SNCCO) extending in a NWW-SEE direction from Xiaoqinling, through Lushan, Wuyang and Huoqiu, to Bengbu, finally truncated by the Tanlu Fault in the east, with a total length of >800 km. Indeed, extensive Paleoproterozoic metamorphism along the southeastern margin and the southern segment of the Jiao-Liao-Ji Belt (Zhou et al., 2008; Guo and Li, 2009; Liu et al., 2009a; Tam et al., 2011a,b), probably supports the existence of the SNCCO. Thus the Paleoproterozoic evolution of the NCC is more complex than previously thought.

More and more lines of evidence suggest that the 2.7-2.8 Ga is an important crustal growth period in the NCC, which is compatible with the growth of other cratons worldwide. Numerous investigations also indicate that - 2.5 Ga subduction, active continental margin arc activity and crustal accretion are widespread in the NCC, indicating that the - 2.5 Ga crustal growth occurs in arc setting (Liu et al., 2007; Diwu et al., 2011; Wang et al., 2011; Zhou et al., 2011). However, it is notable that voluminous - 2.5 Ga crustal growth occurred in mantle plume setting (Yang et al., 2008; Grant et al., 2009; Geng et al., 2010; Zhang et al., 2011a). More work is needed to further constrain the evolution and tectonic division of the NCC, but there is little doubt that the 2.7-2.8 Ga crustal-formation is much wider than that previously considered.

6. Conclusions

From the above zircon Hf isotope data in combination with the age and geochemistry data, some important conclusions can be drawn in the following:

(1) Different divisions of the NCC have different zircon Hf isotope compositions. The Eastern block (EB) is characterized by minor crustal growth at -3.4, -3.6 and - 3.9 Ga and the main crustal growth at 2.7-2.8 Ga with local crustal accretion at 2.5-2.6 Ga; the TNCO is characterized by 2.5-2.8 Ga crustal growth, with some areas being mainly at 2.5-2.6 Ga and other areas at 2.7-2.8 Ga with minor early-to middle-Archean crustal materials; the Yinshan block is mainly characterized by - 2.7 Ga crustal growth as revealed by detrital zircons from the Zhaertai Group and supports source material to the Khondalites; detrital zircons of khon-dalites in the Khondalite Belt reveal the main crustal-forma-tion of the Western block (WB) in Paleoproterozoic with remelting of some 2.6 Ga and minor >2.7 Ga crustal materials; Paleoproterozoic crustal growth is minor in the eastern

block and TNCO. The crustal growth at ~2.5Ga involve both arc and mantle plume settings,

(2) The 2.7—2.8 Ga magmatism and crustal growth most probably occurred widely in the NCC, which is further supported by the zircon Hf isotope data of modern river sediments, overlying sedimentary cover, Precambrian lower crustal rocks and Neoarchean syenogranites. Thus, 2.7—2.8 Ga crustal growth and magmatism may be underestimated due to strong 2.5—2.6 Ga tectono-thermal events, poor exposure and insufficient data,

(3) The evolution and tectonic subdivision of the NCC are more complex than previously suggested, involving multi-stage crustal growth and multiple tectono-thermal events.

Acknowledgments

This study was supported by the National Natural Science Foundation of China (Grant Nos. 90814008, 40634023 and 40973043) and the National Basic Research Program of China (Grant No. 2009CB825002). Critical reviews and many useful suggestions by Prof. M. Santosh, Prof. Guochun Zhao (University of Hong Kong) and an anonymous reviewer have greatly improved the final version of the manuscript.

References

Amelin, Y., Lee, D.C., Halliday, A.N., Pidgeon, R.T., 1999. Nature of the Earth's earliest crust from hafnium isotopes in single detrital zircons. Nature 399, 252-255. Armstrong, R.L., 1981. Radiogenic isotopes: the case for crustal recycling on a near-steady state no-continental-growth Earth. Philosophical Transactions of the Royal Society of London. Series A, Mathematical and Physical Sciences 301, 443-472. Arnde, N.T., Goldstein, S.L., 1987. Use and abuse of crust-formation ages.

Geology 15, 893-895. Belousova, E.A., Griffin, W.L., O'Reily, S.Y., Fisher, N.L., 2002. Igneous zircon: trace element composition as an indicator of source rock type. Contributions to Mineralogy and Petrology 143, 602-622. Belousova, E.A., Kobayashi, K.L., Griffin, W.L., Begg, G.S., O'Reilly, S.Y., Pearson, D.G., 2010. The growth of the continental crust: constraints from zircon Hf-isotope data. Lithos 119 (3-4), 457-466. Bibikova, E., 2003. Isotope-geochemical Characteristics of the Archaean Sanukitoids: A Review. EGS - AGU - EUG Joint Assembly, Abstracts from the meeting held in Nice, France, 6-11 April. abstract #1275. Chen, B., Liu, S.W., Wang, R., Chen, Z.C., Liu, C.Q., 2006a. Nd-Sr isotopic geochemistry of the late Archean-Paleoproterozoic granitoids in the Luliang-Wutai Terrain, North China Craton and implications for petrogenesis. Acta Geologica Sinica 80 (6), 834-843. Chen, B., Liu, S.W., Geng, Y.S., Liu, C.Q., 2006b. Zircon U-Pb ages, Hf isotopes and significance of the late Archean-Paleoproterozoic granitoids from the Wutai-Luuliang terrain, North China. Acta Petrologica Sinica 22 (2), 269-304 (in Chinese with English abstract). Chen, L., 2007. Geochronology and Geochemistry of the Guyang Greenstone Belt. Post-Doctorate Report. Institute of Geology and Geophysics, Chinese Academy of Sciences, Beijing, pp. 1-40 (in Chinese with English abstract).

Cherniak, D.J., Watson, E.B., 2000. Pb diffusion in zircon. Chemical

Geology 172, 5-24. Cherniak, D.J., Watson, E.B., 2003. Diffusion in zircon. Reviews in

Mineralogy and Geochemistry 53, 113-143. Condie, K.C., 1998. Episodic continental growth and supercontinents: a mantle avalanche connection? Earth and Planetary Science Letters 163, 97-108.

Condie, K.C., 2000. Episodic continental growth models: afterthoughts and extensions. Tectonphysics 322, 153-162.

Condie, K.C., Belousova, E., Griffin, W.L., Sircombe, K.N., 2009. Granitoid events in space and time: constraints from igneous and detrital zircon age spectra. Gondwana Research 15, 228-242.

Condie, K.C., Aster, R.C., 2010. Episodic zircon age spectra of orogenic granitoids: the supercontinent connection and continental growth. Precambrian Research 180, 227-236.

Dan, W., Li, X.H., Guo, J.H., Liu, Y., Wang, X.C., 2011. Paleoproterozoic evolution of the eastern Alax block, westernmost North China: evidence from in situ zircon U-Pb and Hf-O isotopes. Gondwana Research. doi:10.1016/j.gr.2011.09.004.

Darby, B.J., Gehrels, G., 2006. Detrital zircon reference for the North China block. Journal of Asian Earth Sciences 26, 637-648.

Diwu, C.R., Sun, Y., Lin, C.L., Liu, X.M., Wang, H.L., 2007. Zricon U-Pb ages and Hf isotopes and their geological significance of Yiyang TTG gneisses from Henan Province, China. Acta Petrologica Sinica 23 (2), 253-262 (in Chinese with English abstract).

Diwu, C.R., Sun, Y., Yuan, H.L., Wang, H.L., Zhong, X.P., Liu, X.M., 2008. U-Pb ages and Hf isotopes for detrital zircons from quartzite in the Paleoproterozoic Songshan Group on the southwestern margin of the North China Craton. Chinese Science Bulletin 53 (18), 2828-2839.

Diwu, C.R., Sun, Y., Lin, C.L., Wang, H.L., 2010. LA-(MC)-ICPMS U-Pb zircon geochronology and Lu-Hf isotope compositions of the Taihua complex on the southern margin of the North China Craton. Chinese Science Bulletin 55 (23), 2557-2571.

Diwu, C.R., Sun, Y., Guo, A.L., Wang, H.L., Liu, X.M., 2011. Crustal growth in the North China Craton at —2.5 Ga: evidence from in situ zircon U-Pb ages, Hf isotopes and whole-rock geochemistry of the Deng complex. Gondwana Research 20, 149-170.

Dong, C.Y., Liu, D.Y., Li, J.J., Wan, Y.S., Zhou, H.Y., Li, C.D., Yang, Y.H., Xie, L.W., 2007. Paleoproterozoic Khondalite Belt in the western North China Craton: new evidence from SHRIMP dating and Hf isotope composition of zircons from metamorphic rocks in the Bayan U-Helan mountain area. Chinese Science Bulletin 52, 2984-2994.

Dong, C.Y., Liu, D.Y., Wan, Y.S., Xu, Z.Y., Wang, W., Xie, H.Q., 2009. Hf isotope composition and REE pattern of zircons from early Precam-brian metamorphic rocks in the Daqing mountains, Inner Mongolia. Geological Review 55 (4), 509-520 (in Chinese with English abstract).

Du, L.L., Yang, C.H., Zhuang, Y.X., Wei, R.Z., Wan, Y.S., Ren, L.D., Hou, K.J., 2010a. Hf isotopic composition of zircons from 2.7 Ga metasedimentary rocks and biotite-plagioclase gneiss in the Mengjiatun formation complex, western Shandong Province. Acta Geologica Sinica 84 (7), 991-1001 (in Chinese with English abstract).

Du, L.L., Yang, C.H., Guo, J.H., Wang, W., Ren, L.D., Wan, Y.S., Geng, Y.S., 2010b. The age of the base of the Paleoproterozoic Hutuo Group in the Wutai mountains area, North China Craton: SHRIMP zircon U-Pb dating of basaltic andesite. Chinese Science Bulletin 55 (3), 246-254.

Faure, M., Lin, W., Monie, P., Bruguier, O., 2004. Palaeoproterozoic arc magmatism and collision in Liaodong Peninsula (north-east China). Terra Nova 16, 75-80.

Faure, M., Trap, P., Lin, W., Monie, P., Bruguier, O., 2007. Polyorogenic evolution of the Paleoproterozoic Trans-North China Belt, new insights from the Lüliangshan-Hengshan-Wutaishan and Fuping massifs. Episodes 30, 1-12.

Gao, S., Rudnick, R.L., Yuan, H.L., Liu, X.M., Liu, Y.S., Xu, W.L., Ling, W.L., Ayers, J., Wang, X.C., Wang, Q.H., 2004. Recycling lower continental crust in the North China Craton. Nature 2432, 892-897.

Gao, L.Z., Zhao, T., Wan, Y.S., Zhao, X., Ma, Y.S., Yang, S.Z., 2005a. Zircon SHRIMP U-Pb age of the Yuntaishan Precambrian meta-morphic basement, Jiaozuo, Henan, China. Geological Bulletin of China 24 (12), 1089-1093 (in Chinese with English abstract).

Gao, S., Zhou, L., Ling, W.L., Liu, Y.S., Zhou, D.W., 2005b. Age and geochemistry of volcanic rocks of Angou Group at the Archean-Proterozoic boundary. Earth Science-Journal of China University of Geosciences 30 (3), 259-263 (in Chinese with English abstract).

Gardés, E., Montel, J.M., 2009. Opening and resetting temperatures in heating geochronological systems. Contributions to Mineralogy and Petrology 158, 185-195.

Geng, Y.S., Liu, F.L., Yang, C.H., 2006. Magmatic event at the end of the Archean in eastern Hebei Province and its geological implication. Acta Geologica Sinica 80 (6), 819-833.

Geng, Y.S., Shen, Q.H., Ren, L.D., 2010. Late Neoarchean to early Pale-oproterozoic magmatic events and tectonothermal systems in the North China Craton. Acta Petrologica Sinica 26 (7), 1945-1966 (in Chinese with English abstract).

Geng, Y.S., Du, L.L., Ren, L.D., 2011. Growth and reworking of the early Precambrian continental crust in the North China Craton: constraints from zircon Hf isotopes. Gondwana Research. doi:10.1018/j.gr.2011.07.006.

Grant, M.L., Wilde, S.A., Wu, F.Y., Yang, J.H., 2009. The application of zircon cathodoluminescence imaging Th-U-Pb chemistry and U-Pb ages in interpreting discrete magmatic and high-grade metamorphic events in the North China Craton at the Archean/Proterozoic boundary. Chemical Geology 261, 155-171.

Griffin, W.L., Pearson, N.J., Belousova, E., Jachson, S.E., Achterbergh, E.V., O'Reilly, Y., Shee, S.R., 1999. The Hf isotope composition of cratonic mantle: LAM-MC-ICPMS analysis of zircon megacrysts in kimberlites. Geochimica et Cosmochimica Acta 64 (1), 133-147.

Griffin, W.L., Wang, X., Jackson, S.E., Pearson, N.J., O'Reilly, S.Y., Xu, W., Zhou, X., 2002. Zircon chemistry and magma mixing, SE China: in-situ analysis of Hf isotopes, Tonglu and Pingtan igneous complexes. Lithos 51, 237-269.

Guan, H., Sun, M., Wilde, S.A., Zhou, X.H., Zhai, M.G., 2002. SHRIMP U-Pb zircon geochronology of the Fuping complex: implications for formation and assembly of the North China Craton. Precambrian Research 113, 1-18.

Guo, J.H., Zhai, M.G., 2001. Sm-Nd age dating of high-pressure granulites and amphibolites from the Sanggan area, North China Craton. Chinese Science Bulletin 46, 106-110.

Guo, J.H., Sun, M., Chen, F.K., Zhai, M.G., 2005. Sm-Nd and SHRIMP U-Pb zircon geochronology of high-pressure granulites in the Sanggan area, North China Craton: timing of Paleoproterozoic continental collision. Journal of Asian Earth Sciences 24, 629-642.

Guo, J.H., Chen, Y., Peng, P., Liu, F., Chen, L., Zhang, L.Q., 2006. Sapphirine granulite from Daqingshan area, inner Modolia-1.85 Ga ultrahigh temperature (UHT) metamorphism. In: Proceedings of National Conference on Petrology and Geodynamics in China (Nanjing), pp. 215-218 (in Chinese).

Guo, L.S., Liu, S.W., Liu, Y.L., Tian, W., Yu, S.Q., Luü, Y.J., 2008. Zircon Hf isotopic features of TTG gneisses and formation environment of Precambrian Sushui complex in Zhongtiao mountains. Acta Petrolog-ica Sinica 24 (1), 139-148 (in Chinese with English abstract).

Guo, S.S., Li, S.G., 2009. SHRIMP zircon U-Pb ages for the Paleo-proterozoic metamorphic-magmatic events in the southeastern margin of the North China. Science China Series D-Earth Science 52 (8), 1039-1045.

Halls, H.C., Li, J.H., Davis, D., Hou, G.T., Zhang, B.X., Qian, X.L., 2000. A precisely dated Proterozoic palaeomagnetic pole from the North China Craton, and its relevance to palaeocontinental reconstruction. Geophysics Journal of International 143, 185-203.

Hawkesworth, C.J., Kemp, A.I.S., 2006. Using hafnium and oxygen isotopes in zircons to unravel the record of crustal evolution. Chemical Geology 226, 144-162.

He, Y., Zhao, G., Sun, M., Xia, X., 2009. SHRIMP and LA-ICP-MS zircon geochronology of the Xiong'er volcanic rocks: implications for the Paleo-Mesoproterozoic evolution of the southern margin of the North China Craton. Precambrian Research 168, 213-222.

Hermann, J., Rubatto, D., Korsakov, A., 2001. Multiple zircon growth during fast exhumation of diamond-iferous, deeply subducted continental crust (Kokchetav massif, Kazakhstan). Contributions to Mineralogy and Petrology 141, 66-82.

Huang, J.Q., 1977. The basic outline of China tectonics. Acta Geologica Sinica 52, 117-135 (in Chinese).

Huang, X.L., Niu, Y.L., Xu, Y.G., Yang, Q.J., Zhong, J.W., 2010. Geochemistry of TTG and TTG-like gneisses from Lushan—Taihua complex in the southern North China Craton: implications for late Archean crustal accretion. Precambrian Research 182, 43—56.

Hurley, P.M., Rand, J.R., 1969. Pre-drift continental nuclei. Science 164, 1229—1242.

Moorbath, S., 1978. Age and isotope evidence for evolution of continental crust. Philosophical Transactions of the Royal Society of London. Series A, Mathematical and Physical Sciences 288, 401—412.

Hou, G.T., Li, J.H., Yang, M.H., Yao, W.H., Wang, C.C., Wang, Y.X., 2008. Geochemical constraints on the tectonic environment of the late Paleoproterozoic mafic dyke swarms in the North China Craton. Gondwana Research 13, 103—116.

Iizuka, T., Komiya, T., Rino, S., Maruyama, S., Hirata, T., 2010. Detrital zircon evidence for Hf isotopic evolution of granitoid crust and continental growth. Geochimica et Cosmochimica Acta 74, 2450—2472.

Jahn, B.M., Auvray, B., Cornichet, J., Bai, Y.L., Shen, Q.H., Liu, D.Y., 1987. 3.5 Ga old amphibolites from eastern Hebei Province, China: field occurrence, petrography, Sm-Nd isochron age and REE geochemistry. Precambrian Research 34, 311—346.

Jahn, B.M., Auvray, B., Shen, Q.H., Liu, D.Y., Zhang, Z.Q., Dong, Y.J., Ye, X.J., Zhang, Q.Z., Cornichet, J., Mace, J., 1988. Archean crustal evolution in China: the Taishan complex, and evidence for juvenile crustal addition from long-term depleted mantle. Precambrian Research 38, 381—403.

Jahn, B.M., Liu, D., Wan, Y., Song, B., Wu, J., 2008. Archean crustal evolution of the Jiadong Peninsula, China, as revealed by zircon SHRIMP geochronology, elemental and Nd-isotope geochemistry. American Journal of Science 308, 232—269.

Jiang, N., Guo, J.H., Zhai, M.G., Zhang, S.Q., 2010. ~ 2. Ga crust growth in the North China Craton. Precambrian Research 179, 37—49.

Jian, P., Zhang, Q., Liu, D.Y., Jin, W.J., Jia, X.Q., Qian, Q., 2005. SHRIMP dating and geological significance of late Archaean high-Mg diorite (sanukite) and hornblende-granite at Guyang of Inner Mongolia. Acta Petrologica Sinica 21 (1), 151 —157 (in Chinese with English abstract).

Jiao, S.J., Guo, J.H., 2011. Application of the two-feldspar geo-thermometer to ultrahigh-temperature (UHT) rocks in the Khondalite Belt, North China Craton and its implications. American Mineralogist 96, 250—260.

Jiao, S.J., Guo, J.H., Mao, Q., Zhao, R., 2011. Application of the Zr-in-rutile thermometry: a case study from ultrahigh temperature granu-lites of the Khondalite Belt, North China Craton. Contributions to Mineralogy and Petrology 162, 379—393.

King, E.W., Valley, J.W., Davis, D.W., Edwards, G.R., 1998. Oxygen isotope ratios of Archaean plutonic zircons from granite—greenstone belts of the Superior Province: indicator of magmatic source. Precambrian Research 92, 47—67.

Kovalenko, A., Clemens, J.D., Savatenkov, V., 2005. Petrogenetic constraints for the genesis of Archaean sanukitoid suites: geochemistry and isotopic evidence from Karelia, Baltic Shield. Lithos 79, 147—160.

Krabbendam, M., Prave, T., Cheer, D., 2008. A fluvial origin for the Neoproterozoic Morar Group, NW Scotland: implications for Torrid-on—Morar Group correlation and the Grenville Orogen foreland basin. Journal of the Geological Society 165, 379—394.

Kröner, A., Compston, W., Zhang, G.W., Guo, A.L., Todt, W., 1988. Age and tectonic setting of late Archean greenstone—gneiss terrain in Henan Province, China, as revealed by single-grain zircon dating. Geology 16, 211—215.

Kroner, A., Cui, W.Y., Wang, S.Q., Wang, C.Q., Nemchin, A.A., 1998. Single zircon ages from high-grade rocks of the Jianping complex, Liaoning Province, NE China. Journal of Asian Earth Sciences 16, 519—532.

Kröner, A., Wilde, S.A., O'Brien, P.J., Li, J.H., Passchier, C.W., Walte, N.P., Liu, D.Y., 2005a. Field relationships, geochemistry, zircon ages and evolution of a late Archaean to Palaeoproterozoic lower crustal section in the Hengshan Terrain of North China. Acta Geologica Sinica 79 (5), 605—629.

Kröner, A., Wilde, S.A., Li, J.H., Wang, K.Y., 2005b. Age and evolution of a late Archean to Paleoproterozoic upper to lower crustal section in the Wutaishan/Hengshan/Fuping terrain of northern China. Journal of Asian Earth Sciences 24, 577—595.

Kroner, A., Wilde, S.A., Zhao, G.C., O'Brien, P.J., Sun, M., Liu, D.Y., Wan, Y.S., Liu, S.W., Guo, J.H., 2006. Zircon geochronology and metamorphic evolution of mafic dykes in the Hengshan complex of northern China: evidence for late Paleoproterozoic extension and subsequent high-pressure metamorphism in the North China Craton. Precambrian Research 146, 45—67.

Kroner, A., 2010. The Role of Geochronology in Understanding Continental Evolution, vol. 338. Geological Society of London, Special Publications. 179—196.

Kusky, T.M., Li, J.H., 2003. Paleoproterozoic tectonic evolution of the North China Craton. Journal of Asian Earth Sciences 22, 383—397.

Kusky, T.M., Windley, B.F., Zhai, M.G., 2007a. Tectonic Evolution of the North China Block: From Orogen to Craton to Orogen. Geological Society of London, Special Publications. vol. 280, 1—34.

Kusky, T.M., Li, J.H., Santosh, M., 2007b. The Paleoproterozoic north Hebei Orogen: North China Craton's collisional suture with the Columbia supercontinent. Gondwana Research 12, 4—28.

Kusky, T.M., 2011. Geophysical and geological tests of tectonic models of the North China Craton. Gondwana Research 20 (1), 26—35.

Lee, J., Williams, I., Eillis, D., 1997. Pb, U and Th diffusion in nature zircon. Nature 390, 159—162.

Li, S.Z., Zhao, G.C., Sun, M., Han, Z.Z., Luo, Y., Hao, D.F., Xia, X.P., 2005. Deformation history of the Paleoproterozoic Liaohe assemblage in the eastern block of the North China Craton. Journal of Asian Earth Sciences 24, 659—674.

Li, S.Z., Zhao, G.C., Sun, M., Han, Z.Z., Zhao, G.T., Hao, D.F., 2006. Are the south and north Liaohe Groups of North China Craton different exotic terranes? Nd isotope constraints. Gondwana Research 9, 198—208.

Li, J.H., Kusky, T., 2007. A late Archean foreland fold and thrust belt in the North China Craton: implications for early collisional tectonics. Gondwana Research 12, 47—66.

Li, S.Z., Zhao, G.C., 2007. SHRIMP U-Pb zircon geochronology of the Liaoji granitoids: constraints on the evolution of the Paleoproterozoic Jiao-Liao-Ji Belt in the eastern block of the North China Craton. Precambrian Research 158, 1—16.

Li, Q.L., Chen, F., Guo, J., Li, X.H., Yang, Y.H., Siebel, W., 2007. Zricon ages and Nd-Hf isotopic composition of the Zhaertai Group (Inner Mongolia): evidence for early Proterozoic evolution of the northern North China Craton. Journal of Asian Earth Sciences 30, 573—590.

Li, Q.G., Liu, S.W., Wang, Z.Q., Chu, Z.Y., Song, B., Wang, Y.B., Wang, T., 2008. Contrasting provenance of late Archean metasedi-mentary rocks from the Wutai complex, North China Craton: detrital zircon U-Pb, whole-rock Sm-Nd isotopic, and geochemical data. International Joural of Earth Science 97, 443—458.

Li, T.S., Zhai, M.G., Peng, P., Chen, L., Guo, J.H., 2010. Ca.2.5 billion year old coeval ultramafic-mafic and syenitic dykes in eastern Hebei: implications for cratonization of the North China Craton. Precambrian Research 180, 143—155.

Li, X.P., Yang, Z.Y., Zhao, G.C., Grapes, R., Guo, J.H., 2011a. Geochro-nology of khondalite-series rocks of the Jining complex: confirmation of depositional age and tectonometamorphic evolution of the North China Craton. International Geology Review 53 (10), 1194—1211.

Li, S.Z., Zhao, G.C., Santosh, M., Liu, X., Dai, L.M., 2011b. Palae-oproterozoic tectonothermal evolution and deep crustal processes in the Jiao-Liao-Ji Belt, North China Carton: a review. Geological Journal. doi:10.1002/gj.1282.

Liu, D.Y., Nutman, A.P., Compston, W., Wu, J.S., Shen, Q.H., 1992. Remnants of >3800 Ma crust in the Chinese part of the Sino-Korean craton. Geology 20, 339—342.

Liu, S.W., Pan, Y.M., Li, J.H., Li, Q.G., Zhang, J., 2002. Geological and isotopic geochemical constraints on the evolution of the Fuping complex, North China Craton. Precambrian Research 117, 41—56.

Liu, S.W., Zhao, G.C., Wilde, S.A., Shu, G.M., Sun, M., Li, Q.G., Tian, W., Zhang, J., 2006a. Th-U-Pb monazite geochronology of the

Luliang and Wutai complex: constraints on the tectonothermal evolution of the Trans-North China Orogen. Precambrian Research 148, 205—224.

Liu, C.H., Liu, S.W., Li, Q.G., Lü, Y.J., Park, K.H., Song, Y.S., 2006b. Petrogenesis of the Paleoproterozoic Guandishan Granitoids in Shanxi Province: constraints from geochemistry and Nd isotopes. Acta Geologica Sinica 80 (6), 925—935.

Liu, D.Y., Wan, Y.S., Wu, J.S., Wilde, S.A., Zhou, H.Y., Dong, C.Y., Yin, X.Y., 2007. Eoarchean rocks and zircons in the North China Craton. In: Van Kranendonk, M.J., Smithies, R.H., Bennett., V. (Eds.), Earth's Oldest Rocks, pp. 251—273.

Liu, D.Y., Wilde, S.A., Wan, Y.S., Wu, J.S., Zhou, H.Y., Dong, C.Y., Yin, X.Y., 2008. New U-Pb and Hf isotopic data confirm Anshan as the oldest preserved segment of the North China Craton. American Journal of Science 308, 200—231.

Liu, Y.C., Wang, A.D., Rolfo, F., Groppo, C., Gu, X.F., Song, B., 2009a. Geochronological and petrological constraints on Paleoproterozoic granulite facies metamorphism in southeastern margin of the North China Craton. Journal of Metamorphic Geology 27, 125—138.

Liu, F., Guo, J.H., Lu, X.P., Diwu, C.R., 2009b. Crustal growth at —2.5 Ga in the North China Craton: evidence from whole-rock Nd and zircon Hf isotopes in the Huai'an gneiss terrane. Chinese Science Bulletin 54, 4704—4713.

Liu, D.Y., Wilde, S.A., Wan, Y.S., Guo, A.L., Wang, H.L., Liu, X.M., 2009c. Combined U-Pb, hafnium and oxygen isotope analysis of zircons from meta-igneous rocks in the southern North China Craton reveal multiple events in the late Mesoarchean—early Neoarchean. Chemical Geology 261, 139—153.

Liu, S.J., Li, J.H., Santosh, M., 2010. First application of the revised Ti-in-zircon geothermometer to Paleoproterozoic ultrahigh-temperature granulites of Tuguiwala, Inner Mongolia, North China Craton. Contributions to Mineralogy and Petrology 159, 225—235.

Liu, S.W., Santosh, M., Wang, B.W., Bai, X., Yang, P.T., 2011a. Zircon U-Pb chronology of the Jianping complex: implications fro the Precambrian crustal evolution history of the northern margin of North China Craton. Gondwana Research 20, 48—63.

Liu, S.W., Lü, Y.J., Wang, W., Yang, P.T., Bai, X., Feng, Y.G., 2011b. Petrogenesis of the Neoarhean granitoid gneisses in northern Hebei Province. Acta Petrologica Sinica 27 (4), 909—921 (in Chinese with English abstract).

Liu, C.H., Zhao, G.C., Sun, M., Zhang, J., He, Y.H., Yin, C.Q., Wu, F.Y., Yang, J.H., 2011c. U-Pb and Hf isotopic study of detrital zircons from the Hutuo Group in the Trans-North China Orogen and its tectonic implications. Gondwana Research 20, 106—121.

Liu, C.H., Zhao, G.C., Sun, M., Wu, F.Y., Yang, J.H., Yin, C.Q., Leung, W.H., 2011d. U-Pb and Hf isotopic study of detrital zircons from the Yejishan Group of the Lüuliang complex: constraints on the timing of collision between the eastern and western blocks, North China Craton. Sedimentary Geology 236, 129—140.

Liu, C.H., Zhao, G.C., Sun, M., Zhang, J., Yin, C.Q., 2011e. U-Pb geochronology and Hf isotope geochemistry of detrital zircons from the Zhongtiao complex: constraints on the tectonic evolution of the Trans-North China Orogen. Precambrian Research. doi:10.1016/ j.precamres.2011.08.007.

Liu, Y.-C., Gu, X., Li, S., Hou, Z.H., Song, B., 2011f. Multistage meta-morphic events in granulitized eclogites from the north Dabie complex zone, central China: evidence from zircon U-Pb age, trace element and mineral inclusion. Lithos 122, 107—121.

Lu, S.N., Yang, C.L., Li, H.K., Li, H.M., 2002. A group of rifting events in the terminal Paleoproterozoic in the North China Craton. Gondwana Research 5 (1), 123—131.

Lu, X.P., Wu, F.Y., Lin, J.Q., Sun, D.Y., Zhang, Y.W., Guo, G.L., 2004. Geochronological successions of the early Precambrian granitic mag-matism in southern Liaodong Peninsula and its constraints on tectonic evolution of the North China Craton. Chinese Journal of Geology 39 (1), 123—138 (in Chinese with English abstract).

Lu, X.P., Wu, F.Y., Guo, J.H., Wilde, S.A., Yang, J.H., Liu, X.M., Zhang, X.O., 2006. Zircon U-Pb geochronological constraints on the

Paleoproterozoic crustal evolution of the eastern block in the North China Craton. Precambrian Research 146, 138—164.

Lu, S.N., Zhao, G.C., Wang, H.C., Hao, G.J., 2008. Precambrian meta-morphic basement and sedimentary cover of the North China Craton: a review. Precambrian Research 160, 77—93.

Luo, Y., Sun, M., Zhao, G.C., Li, S.Z., Xu, P., Ye, K., Xia, X.P., 2004. LA-ICP-MS U-Pb zircon ages of the Liaohe Group in the eastern block of the North China Craton: constraints on the evolution of the Jiao-Liao-Ji Belt. Precambrian Research 134, 349—371.

Luo, Y., Sun, M., Zhao, G.C., Li, S.Z., Xia, X.P., 2006. La-ICP-MS U-Pb zircon geochronology of the Yushulazi Group in the eastern block, North China Craton. International Geology Review 48, 828—840.

Luo, Y., Sun, M., Zhao, G.C., Ayers, J.C., Li, S.Z., Xia, X.P., Zhang, J.H., 2008. A comparison of U-Pb and Hf isotopic composition of detrital zircons from the north and south Liaohe Group: constraints on the evolution of the Jiao-Liao-Ji Belt, North China Craton. Precambrian Research 163, 279—306.

Möller, A., O'Broen, P.J., Kennedy, A., Krüner, A., 2003. Linking Growth Episodes of Zircon and Metamorphic Textures to Zircon Chemistry: An Example from the Ultrahigh-temperature Granulites of Rogaland (SW Norway), vol. 220. Geological Society of London, Special Publications. 65—81.

Nutman, A.P., Wan, Y.S., Liu, D.Y., 2009. Integrated field geological and zircon morphology evidence for ca.3.8 Ga rocks at Anshan: comment on "zircon U-Pb and Hf isotopic constraints of the early Archean crustal evolution in Anshan of the North China Craton" by Wu et al. Precambrian Research 167 (2008), 339—362. Precambrian Research 172, 357—360.

Nutman, A.P., Wan, Y.S., Du, L.L., Friend, C.R.L., Dong, C.Y., Xie, H.Q., Wang, W., Sun, H.Y., Liu, D.Y., 2011. Multistage late Neoarchaean crustal evolution of the North China Craton, eastern Hebei. Precam-brian Research 189 (1—2), 43—65.

Peng, P., Zhai, M.G., Ernst, R.E., Guo, J.H., Liu, F., Hu, B., 2008. A 1.78 Ga large igneous province in the North China Craton: the Xiong'er Volcanic Province and the North China dyke swarm. Lithos 101, 260—280.

Peng, P., 2010. Reconstruction and Interpretation of Giant Mafic Dyke Swarms: A Case Study of 1.78 Ga Magmatism in the North China Craton, vol. 338. Geological Society of London, Special Publications. 163—178.

Piper, J.D.A., Zhang, J.S., Huang, B.C., Roberts, A.P., 2011. Palae-omagnetism of Precambrian dyke swarms in the North China shield: the ~ 1.8 Ga LIP event and crustal consolidation in late Palae-oproterozoic times. Journal of Asian Earth Sciences 41, 504—524.

Polat, A., Kusky, T., Li, J.H., Fryer, B., Kerrich, R., Patrick, K., 2005. Geochemistry of Neoarchean (ca. 2.55—2.50 Ga) volcanic and ophiolitic rocks in the Wutaishan greenstone belt, central orogenic belt, North China Craton: implications for geodynamic setting and continental growth. GSA Bulletin 117 (11 — 12), 1387—1399.

Polat, A., Li, J., Fryer, B., Kusky, T., Gagnon, J., Zhang, S., 2006. Geochemical characteristics of the Neoarchean (2800—2700 Ma) Taishan greenstone belt, North China Craton: evidence for plume— craton interaction. Chemical Geology 230, 60—87.

Ren, R., Han, B.F., Zhang, Z.C., Li, J.F., Yang, Y.H., Zhang, Y.B., 2011. Zircon U-Pb and Hf isotopic studies of basement gneiss and overlying Meso—Neoproterozoic sedimentary rocks from the Changping area, Beijing, and their geological implications. Acta Petrologica Sinica 27 (6), 1721—1745 (in Chinese with English abstract).

Rion, S., Komiya, T., Windley, B.F., Katayama, I., Motoki, A., Hirata, T., 2004. Major episodic increase of continental crustal growth determined from zircon ages of river sands: implications for mantle overturns in the early Precambrian. Physics of the Earth and Planetary Interiors 146, 369—394.

Safonova, I., Maruyama, S., Hirata, T., Kon, Y., Rino, S., 2010. LA ICP MS U-Pb ages of detrital zircons from Russia largest rivers: implications for major granitoid events in Eurasia and global episodes of supercontinent formation. Journal of Geodynamics 50, 134—153.

Santosh, M., Sajeev, K., Li, J.H., 2006. Extreme crustal metamorphism during Colombia supercontinent assembly: evidence from North China Craton. Gondwana Research 10, 256—266.

Santosh, M., Wilde, S.A., Li, J.H., 2007. Timing of Paleoproterozoic ultrahigh-temperature metamorphism in the North China Craton: evidence from SHRIMP U-Pb zircon geochronology. Precambrian Research 159, 178—196.

Santosh, M., Tsunogae, T., Ohyama, H., Sato, K., Li, J.H., Liu, S.J., 2008. Carbonic metamorphism at ultrahigh-temperatures: evidence from North China Craton. Earth and Planetary Science Letters 266, 149—165.

Santosh, M., Wan, Y.S., Liu, D.Y., Dong, C.Y., Li, J.H., 2009. Anatomy of zircons from an ultra-hot Orogen: suturing the North China Craton within Columbia supercontinent. Journal of Geology 117, 429—443.

Santosh, M., 2010. Assembling North China Craton within the Columbia supercontinent: the role of double-sided subduction. Precambrian Research 178, 149—167.

Santosh, M., Liu, S.J., Tsunogae, T., Li, J.H., 2011. Paleoproterozoic ultrahigh-temperature granulites in the North China Craton: implications for tectonic models on extreme crustal metamorphism. Precam-brian Research. doi:10.1016/j.precamres.2011.05.003.

Shen, Q.H., Geng, Y.S., Song, B., Wan, Y.S., 2005. New information from the surface outcrops and deep crust of Archaean rocks of the North China and Yangtze blocks, and Qinling-Dabie Orogen Belt. Acta Geologica Sinica 79, 616—627 (in Chinese).

Shirey, S.B., Hanson, G.N., 1984. Mantle-derived Archaean monzodiorites and trachyandesites. Nature 310, 222—224.

Smithise, R.H., Champion, D.C., 2000. The Archaean high-Mg diorite suite: links to tonalite—trondhjemite—granodiorite magmatism and implications for early Archaean crustal growth. Journal of Petrology 41 (12), 1653—1671.

Song, B., Nutman, A.P., Liu, D.Y., Wu, J.S., 1996. 3800 to 2500 Ma crustal evolution in Anshan area of Liaoning Province, northeastern China. Precambrian Research 78, 79—94.

Tam, P.Y., Zhao, G.C., Liu, F.L., Zhou, X.W., Liu, X.M., Sun, M., Li, S.Z., 2011a. Timing of metamorphism in the Paleoproterozoic Jiao-Liao-Ji Belt: new SHRIMP U-Pb zircon dating of granulites, gneisses and marbles of the Jiaobei massif in the North China Craton. Gondwana Research 19, 150—162.

Tam, P.Y., Zhao, G.C., Zhou, X.W., Sun, M., Guo, J.H., Li, S.Z., Yin, C.Q., Wu, M.L., He, Y.H., 2011b. Metamorphic P— T path and implications of high-pressure politic granulites from the Jiaobei massif in the Jiao-Liao-Ji Belt, North China Craton. Gondwana Research. doi:10.1016/ j.gr.2011.09.006.

Tang, J., Zheng, Y.F., Wu, Y.B., Gong, B., Liu, X.M., 2007. Geochronology and geochemistry of metamorphic rocks in the Jiaobei terrane: constraints on its tectonic affinity in the Sulu Orogen. Precambrian Research 152, 48—82.

Trap, P., Faure, M., Lin, W., Monie, P., 2007. Late Paleoproterozoic (1900—1800 Ma) nappe-stacking and polyphase deformation in the Hengshan—Wutaishan area: implications for the understanding of the Trans-North-China Belt, north China Craton. Precambrian Research 156, 85—106.

Trap, P., Faure, M., Lin, W., Bruguier, O., Monie, P., 2008. Contrasted tectonic styles for the Paleoproterozoic evolution of the North China Craton. Evidence for a 2.1 Ga thermal and tectonic events in the Fuping massif. Journal of Structural Geology 30, 1109—1125.

Trap, P., Faure, M., Lin, W., Monie, P., Meffre, S., Melleton, J., 2009a. The Zanhuang massif, the second and eastern suture zone of the Paleoproter-ozoic Trans-North China Orogen. Precambrian Research 172, 80—98.

Trap, P., Faure, M., Lin, W., Monié, P., Meffre, S., 2009b. The Lüliang Massif: A Key Area for the Understanding of the Palaeoproterozoic. Geological Society of London, Special Publications, vol, 323. 99—125.

Trap, P., Fuare, M., Lin, W., Augier, R., Fouassier, A., 2011. Syn-colli-sional channel flow and exhumation of Paleoproterozoic high pressure rocks in the Trans-North China Orogen: the critical role of partial-melting and orogenic bending. Gondwana Research 20 (2—3), 498—515.

Tsunogae, T., Liu, S.J., Santosh, M., Shimizu, H., Li, J.H., 2011. Ultra-high-temperature metamorphism in Daqingshan, inner Mongolia suture zone, North China Craton. Gondwana Research 20 (1), 36—47.

Vervoort, J.D., Patchett, P.J., 1996. Behaviour of hafnium and neodymium isotope in the crust: constraints from Precambrian crustally-derived granites. Geochimica et Cosmochimica Acta 60, 3717—3733.

Vervoort, J.D., Blichert-Toft, J., 1999. Evolution of the depleted mantle: Hf isotope evidence from juvenile rocks through time. Geochimica et Cosmochimica Acta 63, 533—566.

Wan, Y.S., Zhang, Q.D., Song, T.R., 2003. SHRIMP ages of detrital zircons from the Changcheng System in the Ming Tombs area, Beijing: constraints on the protolith nature and maximum depositional age of the Mesoproterozoic cover of the North China Craton. Chinese Science Bulletin 48 (22), 2500—2506.

Wan, Y.S., Liu, D.Y., Song, B., Wu, J.S., Yang, C.H., Zhang, Z.Q., Geng, Y.S., 2005. Geochemical and Nd isotopic compositions of 3.8 Ga meta-quartz dioritic and trondhjemitic rocks from the Anshan area and their geological significance. Journal of Asian Earth Sciences 24, 563—575.

Wan, Y.S., Song, B., Liu, D.Y., Wilde, S.A., Wu, J.S., Shi, Y.R., Yin, X.Y., Zhou, H.Y., 2006a. SHRIMP U-Pb zircon geochronology of Palae-oproterozoic metasedimentary rocks in the North China Craton: evidence for major late Palaeoproterozoic tectonothermal event. Precambrian Research 149, 249—271.

Wan, Y.S., Wilde, S.A., Liu, D.Y., Yang, C.X., Song, B., Yin, X.Y., 2006b. Further evidence for ~ 1.85 Ga metamorphism in the central zone of the North China Craton: SHRIMP U-Pb dating of zircon from meta-morphic rocks in the Lushan area, Henan Province. Gondwana Research 9, 189—197.

Wan, Y.S., Liu, D.Y., Dong, C.Y., Nutman, A., Wilde, S.A., Wang, W., Xie, H.Q., Yin, X.Y., Zhou, H.Y., 2009a. The oldest rocks and zircons in China. Acta Petrologica Sinica 25, 1793—1807 (in Chinese with English abstract).

Wan, Y.S., Liu, D.Y., Dong, C.Y., Xu, Z.Y., Wang, Z.J., Wilde, S.A., Yang, Y.H., Liu, Z.H., Zhou, H.Y., 2009b. The Precambrian Khondalite Belt in the Daqingshan area, North China Craton: evidence for multiple metamorphic events in the Palaeoproterozoic era. Journal of the London Geological Society, Special Publications 323, 73—97.

Wan, Y.S., Liu, D.Y., Wang, S.Y., Zhao, X., Dong, C.Y., 2009c. Early Precambrian crustal evolution in the Dengfeng area, Henan Province (eastern China): constraints from geochemistry and SHRIMP U-Pb zircon dating. Acta Geologica Sinica 83 (7), 982—999 (in Chinese with English abstract).

Wan, Y.S., Liu, D.Y., Wang, S.J., Dong, C.Y., Yang, E.X., Wang, W., Zhou, H.Y., Ning, Z.G., Du, L.L., Yin, X.Y., Xie, H.Q., Ma, M.Z., 2010a. Juvenile magmatism and crustal recycling at the end of the Neoarchean in western Shandong Province, North China Craton: evidence from SHRIMP zircon dating. American Journal of Science 210, 1503—1552.

Wan, Y.S., Miao, P.S., Liu, D.Y., Yang, C.H., Wang, W., Wang, H.C., Wang, Z.J., Dong, C.Y., Du, L.L., Zhou, H.Y., 2010b. Formation ages and source regions of the Paleoproterozoic Gaofan, Hutuo and Dong-jiao groups in the Wutai and Dongjiao areas of the North China Craton from SHRIMP U-Pb dating of detrital zircons: resolution of debates over their straigraphic relationships. Chinese Science Bulletin 55 (7), 572—578.

Wan, Y.S., Dong, C.Y., Wang, W., Xie, H.Q., Liu, D.Y., 2010c. Archean basement and a Paleoproterozoic collision Orogen in the Huoqiu are at the southeastern margin of North China Craton: evidence from sensitive high resolution ion micro-probe U-Pb zircon geochronology. Acta Geologica Sinica 84 (1), 91—104.

Wan, Y.S., Liu, D.Y., Wang, W., Song, T.R., Kroöner, A., Dong, C.Y., Zhou, H.Y., Yin, X.Y., 2011a. Provenance of Meso- to Neoproterozoic cover sediments at the Ming Tombs, Beijing, North China Craton: an integrated study of U-Pb dating and Hf isotopic measurement of detrital zircons and whole-rock geochemistry. Gondwana Research 20, 219—242.

Wan, Y.S., Liu, D.Y., Wang, S.J., Yang, E.X., Wang, W., Dong, C.Y., Zhou, H.Y., Du, L.L., Yang, Y.H., Diwu, C.R., 2011b. ~2.7 Ga juvenile crust formation in the North China Craton (Taishan—Xintai area, western Shandong Province): further evidence of an understated

event from U-Pb dating and Hf isotopic composition of zircon. Precambrian Research 186 (1—4), 169—180.

Wan, Y.S., Dong, C.Y., Liu, D.Y., Krüoner, A., Yang, C.H., Wang, W., Du, L.L., Xie, H.Q., Ma, M.Z., 2011c. Zircon ages and geochemistry of late Neoarchean syenogranites in the North China Craton: a review. Precambrian Research. doi:10.1016/j.precamres.2011.05.001.

Wang, Z.H., Wilde, S.A., Wang, K.Y., 2004. A MORB-arc basalt—adakite association in the 2.5 Ga Wutai greenstone belt: late Archean mag-matism and crustal growth in the North China Craton. Precambrian Research 131, 323—343.

Wang, Y.J., Zhao, G.C., Cawood, P.A., Fan, W.M., Peng, T.P., Sun, L.H., 2008. Geochemistry of Paleoproterozoic (—1770 Ma) mafic dikes from the Trans-North China Orogen and tectonic implications. Journal of Asian Sciences 33, 61—77.

Wang, Y.J., Zhang, Y.Z., Zhao, G.C., Fan, W.M., Xia, X.P., Zhang, F.F., Zhang, A.M., 2009. Zircon U-Pb geochronological and geochemical constraints on the petrogenesis of the Taishan sanukitoids (Shandong): implications for Neoarchean subduction in the east block, North China Craton. Precambrian Research 174, 273—286.

Wang, Z.H., 2009. Tectonic evolution of the Hengshan—Wutai—Fuping complexes and its implication for the Trans-North China Orogen. Precambrian Research 170, 73—87.

Wang, J., Wu, Y., Gao, S., Peng, M., Liu, X.C., Zhao, L.S., Zhou, L., Hu, Z.C., Gong, H.J., Liu, Y.S., 2010a. Zircon U-Pb and trace element data from rocks of the Huai'an complex: new insights into the late Paleoproterzoic collision between the eastern and western blocks of the North China Craton. Precambrian Research 178, 59—71.

Wang, Z.H., Wilde, S.A., Wang, J.L., 2010b. Tectonic setting and significance of 2.3—2.1 Ga magmatic events in the Trans-North China Orogen: new constraints from the Yanmenguan mafic-ultramafic intrusion in the Hengshan—Wutai—Fuping area. Precambrian Research 178, 27—42.

Wang, W., Liu, S., Bai, X., Yang, P., Li, Q., Zhang, L., 2011. Geochemistry and zircon U-Pb-Hf isotopic systematics of the Neoarchean Yix-ian—Fuxin greenstone belt, northern margin of the North China Craton: implications for petrogenesis and tectonic setting. Gondwana Research 20 (1), 64—81.

Wilde, S.A., Cawood, P.A., Wang, K.Y., 1997. The Relationship and Timing of Granitoid Evolution with Respect to Felsic Volcanism in the Wutai Complex, North China Craton. Proceeding of the 30th International Geological Science Publishers, Amsterdam, pp. 75—87.

Wilde, S.A., Zhao, G.C., Sun, M., 2002. Development of the North China Craton during the late Archean and its final amalgamation at 1.8 Ga: some speculations on its positions within a global Palaeoproterozoci supercontinent. Gondwana Research 55 (1), 85—94.

Wilde, S.A., Cawood, P.A., Wang, K.Y., Nemchin, A., Zhao, G.C., 2004. Determining Precambrian Crustal Evolution in China: A Case-study from Wutaishan, Shanxi Province, Demonstrating the Application of Precise SHRIMP U—Pb Geochronology. Geological Society of London, Special Publications, vol. 226, 5—25.

Wilde, S.A., Cawood, P.A., Wang, K.Y., Nemchin, A.A., 2005. Granitoid evolution in the late Archean Wutai complex, North China Craton. Journal of Asian Earth Sciences 24, 597—613.

Wilde, S.A., Valley, J.W., Kita, N.T., Cavosie, A.J., Liu, D.Y., 2008. SHRIMP U-Pb and CAMECA 1280 oxygen isotope results from ancient detrital zircons in the Caozhuang quartzite, eastern Hebei, North China Craton: evidence for crustal reworking 3.8 Ga age. American Journal of Science 308, 185—199.

Windley, B.F., 1995. The Evolving Continents, third ed. John Wiley and Sons, Chichester, pp. 1—526.

Wu, C.H., Li, S.X., Gao, J.F., 1986. Archean and Paleoproterozoic meta-morphic regions in the North China Craton. In: Dong, S.B. (Ed.), Metamorphism and Crustal Evolution of China. Geological Publishing House, Beijing, pp. 53—89 (in Chinese).

Wu, Y.B., Zheng, Y.F., 2004. Genesis of zircon and its constraints on interpretation of U-Pb age. Chinese Science Bulletin 49, 1554—1569.

Wu, F.Y., Yang, J.H., Liu, X.M., Li, T.S., Xie, L.W., Yang, Y.H., 2005a. Hf isotopes of the 3.8 Ga zircons in eastern Hebei Province, China:

implications for early crustal evolution of the North China Craton. Chinese Science Bulletin 50 (21), 2473 —2480.

Wu, F., Zhao, G., Wilde, S.A., Sun, D.Y., 2005b. Nd isotopic constraints on crustal formation in the North China Craton. Journal of Asian Earth Sciences 24, 523—545.

Wu, F.Y., Zhang, Y.B., Yang, J.H., Xie, L.W., Yang, Y.H., 2008a. Zircon U-Pb and Hf isotopic constraints on the early Archean crustal evolution in Anshan of the North China Craton. Precambrian Research 167, 339—362.

Wu, Y.B., Gao, S., Zhang, H.F., Yang, S.H., Jiao, W.F., Liu, Y.S., Yuan, H.L., 2008b. Timing of UHP metamorphism in the Hong'an area, western Dabie mountains, China: evidence from zircon U-Pb age, trace element and Hf isotope composition. Contributions to Mineralogy and Petrology 155, 123—133.

Wu, M., Zhao, G., Sun, M., Yin, C., Li, S., Tam, P.Y., 2011. Petrology and p—T path of the Yishui mafic granulites: implications for tectono-thermal evolution of the western Shandong complex in the eastern block of the North China Craton. Precambrian Research. doi:10.1016/ j.precamres.2011.08.008.

Woodhead, J., Hergt, T., Shelley, M., 2004. Zircon Hf-isotope analysis with an excimer laser, depth profiling, ablation of complex geometries, and concomitant age estimation. Chemical Geology 209, 121—135.

Xia, X.P., Sun, M., Zhao, G.C., Luo, Y., 2006a. LA-ICP-MS U-Pb geochronology of detrital zircons from the Jining complex, North China Craton and its tectonic significance. Precambrian Research 144, 199—212.

Xia, X.P., Sun, M., Zhao, G.C., Wu, F.Y., Xu, P., Zhang, J.H., Luo, Y., 2006b. U-Pb and Hf isotopic study of detrital zircons from the Wula-shan khondalites: constraints on the evolution of the Ordos Terrane, western block of the North China Craton. Earth and Planetary of Science Letters 241, 581—593.

Xia, X.P., Sun, M., Zhao, G.C., Wu, F.Y., Xu, P., Zhang, J., He, Y.H., Zhang, J.H., 2006c. U-Pb and Hf isotope study of detrital zircons from the Wanzi Supercrustals: constraints on the tectonic setting and evolution of the Fuping Complex, Trans-North China Orogen. Acta Geologica Sinica 80, 844—863.

Xia, X.P., Sun, M., Zhao, G.C., Wu, F.Y., Xu, P., Zhang, J., He, Y.H., 2008. Paleoproterozoic crustal growth in the western block of the North China Craton: evidence from detrital zircon Hf and whole rock Sr-Nd isotopic compositions of the khondalites from the Jining complex. American Journal of Science 308, 304—327.

Xia, X.P., Sun, M., Zhao, G.C., Wu, F.Y., Xie, L.W., 2009. U-Pb and Hf isotopic study of detrital zircons from the Luüliang khondalite, North China Craton, and their tectonic implications. Geological Magazine 146 (5), 701—716.

Xiao, L.L., Wu, C.M., Zhao, G.C., Guo, J.H., Ren, L.D., 2010. Meta-morphic p—T paths of the Zanhuang amphibolites and metapelites: constraints on the tectonic evolution of the Paleoproterozoic Trans-North China Orogen. International Journal of Earth Sciences 100, 717—739.

Xu, S., Griffin, W.L., Ma, X., O'Reilly, S.Y., He, Z., Zhang, C., 2009. The Taihua group on the southern margin of the North China craton: further insights from U-Pb ages and Hf isotope compositions of zircons. Mineralogy and Petrology 97, 43—59.

Yang, J.H., Wu, F.Y., Liu, X.M., Xie, L.W., 2005. Zircon U-Pb ages and Hf isotopes and their geological significances of the Miyun rapakivi granites from Beijing, China. Acta Petrologica Sinica 21 (6), 1633—1644 (in Chinese with English abstract).

Yang, C.X., 2008. Zircon SHRIMP U-Pb ages, geochemical characteristics and environmental evolution of the early Precambrian metamorphic series in the Lushan area, Henan, China. Geological Bulletin of China 27 (4), 517—533 (in Chinese with English abstract).

Yang, J.H., Wu, F.Y., Wilde, S.A., Zhao, G.C., 2008. Petrogenesis and geodynamics of late Archean magmatism in the eastern Hebei, eastern North China Craton: geochronological, geochemical and Nd-Hf isotopic evidence. Precambrian Research 167, 125—149.

Yang, J., Gao, S., Chen, C., Tang, Y., Yuan, H.L., Gong, H., Xie, S., Wang, J., 2009. Episodic crustal growth of North China as revealed by

U-Pb age and Hf isotopes of detrital zircons from modern rivers. Geochimica et Cosmochimica Acta 73, 2660—2673.

Yin, C.Q., Zhao, G.C., Sun, M., Xia, X.P., Wei, C.J., Zhou, X.W., Leung, W.H., 2009. LA-ICP-MS U-Pb zircon ages of the Qianlishan complex: constrains on the evolution of the Khondalite Belt in the western block of the North China Craton. Precambrian Research 174, 78—94.

Yin, C.Q., Zhao, G.C., Guo, J.H., Sun, M., Xia, X.P., Zhou, X.W., Liu, C.H., 2011. U-Pb and Hf isotopic study of zircons of the Helanshan complex: constraints on the evolution of the Khondalite Belt in the western block of the North China Craton. Lithos 122, 25—38.

Zhai, M.G., Bian, A.G., Zhao, T.P., 2000. The amalgamation of the supercontinent of North China Craton ate the end of Neo-Archaean and its breakup during late Palaeoproterozoic and Meso—Proterozoic. Science in China (Series D) 43 (Suppl.), 219—232.

Zhai, M.G., 2004. Precambrian Geological Events in the North China Craton, vol. 226. Geological Society of London, Special Publications. 57—72.

Zhai, M.G., Li, T.S., Peng, P., Hu, B., Liu, F., Zhang, Y.B., 2010. Precambrian Key Tectonic Events and Evolution of the North China Craton, vol. 388. Geological Society of London, Special Publications. 235—262.

Zhai, M.G., Santosh, M., 2011. The early Precambrian odyssey of the North China Craton: a synoptic overview. Gondwana Research 20, 6—25.

Zhang, J., Zhao, G.C., Li, S.Z., Sun, M., Liu, S.W., Xia, X.P., He, Y.H., 2006. U-Pb zircon dating of the granitic conglomerates of the Hutuo Group: affinities of the Wutai granitoids and significance to the tectonic evolution of the Trans-North China Orogen. Acta Geologica Sinica 80 (6), 886—898.

Zhang, S.H., Liu, S.W., Zhao, Y., Yang, J.H., Song, B., Liu, X.M., 2007. The 1.75—1.68 Ga anorthosite—mangerite—alkali granitoid—rapakivi granite suite from the northern North China Craton: magmatism related to a Paleoproterozoic Orogen. Precambrian Research 155, 287—312.

Zhang, H.F., Ying, J.F., Santosh, M., Zhao, G.C., 2011a. Episodic growth of Precambrian lower crust beneath the North China Craton: a synthesis. Precambrian Research. doi:10.1016/j.precamres.2011.04.006.

Zhang, S.J., Zhang, L.C., Xiang, P., Wan, B., Pirajno, F., 2011b. Zircon U-Pb age, Hf isotopes and geochemistry of Shuichang Algoma-type banded iron-formation, North China Craton: constraints on the ore-forming age and tectonic setting. Gondwana Research 20, 137—148.

Zhang, H.F., Zhai, M.G., Santosh, M., Diwu, C.R., Li, S.R., 2011c. Geochronology and petrogenesis of Neoarchean potassic meta-granites from Huai'an complex: implications for the evolution of the North China Craton. Gondwana Research 20, 171—183.

Zhang, J., Zhao, G., Li, S., Sun, M., Chan, L.S., Shen, W., Liu, S.W., 2011d. Structural pattern of the Wutai complex and its constraints on the tectonic framework of the Trans-North China Orogen. Precambrian Research. doi:10.1016/j.precamres.2011.08.009.

Zhao, G.C., Wilde, S.A., Cawood, P.A., Lu, L.Z., 1998. Thermal evolution of the Archaean basement rocks from the eastern part of the North China Craton and its bearing on tectonic setting. International Geology Review 40, 706—721.

Zhao, G.C., Wilde, S.A., Cawood, P.A., Lu, L.Z., 1999. Tectonothermal history of the basement rocks in the western zone of the North China Craton and its tectonic implications. Tectonophysics 310, 37—53.

Zhao, G.C., Cawood, P.A., Wilde, S.A., Sun, M., Lu, L.Z., 2000a. Meta-morphism of basement rocks in the central zone of the North China Craton: implications for Paleoproterozoic tectonic evolution. Precam-brian Research 103, 55—88.

Zhao, G.C., Wilde, S.A., Cawood, P.A., Lu, L.Z., 2000b. Petrology and P— T path of the Fuping mafic granulites: implications for tectonic evolution of the central zone of the North China Craton. Journal of Metamorphic Geology 18, 375—391.

Zhao, G.C., Wilde, S.A., Cawood, P.A., Sun, M., 2001. Archean blocks and their boundaries in the North China Craton: lithological, geochemical, structural and P—T path constraints and tectonic evolution. Precambrian Research 107, 45—73.

Zhao, G.C., Wilde, S.A., Cawood, P.A., Sun, M., 2002. SHRIMP U-Pb zircon ages of the Fuping complex: implications for late Archean to

Paleoproterozoic accretion and assembly of the North China Craton. America Journal of Science 302, 191—226.

Zhao, G.C., Sun, M., Wilde, S.A., Guo, J.H., 2004. Late Archaean to Palae-oproterozoic Evolution of the Trans-North China Orogen: Insights from Synthesis of Existing Data from the Hengshan—Wutai—Fuping Belt, vol. 226. Geological Society of London, Special Publications. 27—55.

Zhao, G.C., Sun, M., Wilde, S.A., Li, S.Z., 2005. Late Archean to Pale-oproterozoic evolution of the North China Craton: key issues revisited. Precambrian Research 136, 177—202.

Zhao, G.C., Kroüner, A., Wilde, S.A., Sun, M., Li, S.Z., Li, X.P., Zhang, J., Xia, X.P., He, Y.H., 2007. Lithotectonic elements and geological events in the Hengshan—Wutai—Fuping Belt: a synthesis and implications for the evolution of the Trans-North China Orogen. Geological Magazine 144 (5), 753—775.

Zhao, G., Wilde, S.A., Sun, M., Guo, J.H., Krüoner, A., Li, S.Z., Li, X.P., Zhang, J., 2008. SHRIMP U-Pb zircon geochronology of the Huai'an complex: constraints on late Archean to Paleoproterozoic magmatic and metamorphic events in the Trans-North China Orogen. American Journal of Science 308, 270—303.

Zhao, G.C., 2009. Metamorphic evolution of major tectonic units in the basement of the North China Craton: key issues and discussion. Acta Petrologica Sinica 25 (8), 1772—1792 (in Chinese with English abstract).

Zhao, T.P., Chen, W., Zhou, M.F., 2009. Geochemical and Nd-Hf isotopic constraints on the origin of the ~ 1.74 Ga anorthosite complex, North China Craton. Lithos 113 (3—4), 673—690.

Zhao, G.C., Wilde, S.A., Guo, J.H., Cawood, P.A., Sun, M., Li, X.P., 2010a. Single zircon grains record two Paleoproterozoic collisional events in the North China Craton. Precambrian Research 177, 266—276.

Zhao, G.C., Yin, C.Q., Guo, J.H., Sun, M., Li, S.Z., Li, X.P., Wu, C.M., Liu, C.H., 2010b. Metamorphism of the Lüliang amphibolite: implications for the tectonic evolution of the North China Craton. American Journal of Science 310, 1480—1502.

Zhao, G., Li, S., Sun, M., Wilde, S.A., 2011. Assembly, accretion, and break-up of the Paleo—Mesoproterozoic Columbia supercontinent: record in the North China Craton revisited. International Geology Review 53 (11—12), 1331 — 1356.

Zheng, J.P., Griffin, W.L., O'Reilly, S.Y., Lu, F.X., Wang, C.Y., Zhang, M., Wang, F.Z., Li, H.M., 2004a. 3.6 Ga lower crust in central China: new evidence on the assembly of the North China Craton. Geology 32 (3), 229—232.

Zheng, J.P., Lu, F.X., Yu, T.M., Tan, H.Y., 2004b. A study on Hf isotope, U-Pb dating and trace elements of granulite enclaves in the Hannuoba basalts: record of early evolution of the lower crust of the North China Craton. Chinese Science Bulletin 49, 375—383.

Zheng, Y.F., Wu, Y.B., Zhao, Z.F., Zhang, S.B., Xu, P., Wu, F.Y., 2005. Metamorphic effect on zircon Lu-Hf and U-Pb isotope systems in ultrahigh-pressure eclogite-facies metagranite and metabasite. Earth and Planetary Science Letters 240, 378—400.

Zheng, Y.F., Zhao, Z.F., Wu, Y.B., Zhang, S.B., Liu, X.M., Wu, F.Y., 2006. Zircon U-Pb age, Hf and O isotope constraints on protolith origin of ultrahigh-pressure eclogite and gneiss in the Dabie Orogen. Chemical Geology 231, 135—158.

Zheng, Y.F., Chen, R.X., Zhang, S.B., Tang, J., Zhao, Z.F., Wu, Y.B., 2007. Zircon Lu—Hf isotope study of ultrahigh-pressure eclogite and granitic gneiss in the Dabie Orogen. Acta Petrologica Sinica 23 (2), 317—330 (in Chinese with English abstract).

Zheng, J.P., Griffin, W.L., O'Reilly, S.Y., Zhao, J.H., Wu, Y.B., Liu, G.L., Pearson, N., Zhang, M., Ma, C.Q., Zhang, Z.H., Yu, C.M., Su, Y.P., Tang, H.Y., 2009. Neoarchean (2.7—2.8 Ga) accretion beneath the North China Craton: U-Pb age, trace elements and Hf isotopes of zircons in diamondiferous kimberlites. Lithos 112, 188—202.

Zhou, X.W., Zhao, G.C., Wei, C.J., Geng, Y.S., Sun, M., 2008. EPMA U-Th-Pb monazite and SHRIMP U-Pb zircon geochronology of high-pressure pelitic granulites in the Jiaobei massif of the North China Craton. America Journal of Science 308, 328—350.

Zhou, Y.Y., Zhao, T.P., Xue, L.W., Wang, S.Y., Gao, J.F., 2009a. Petro-logical, geochemical and chronological constraints for the origin and geological significance of Neoarchean TTG gneiss in the Songshan

area, North China Craton. Acta Petrologica Sinica 25 (2), 331—347 (in Chinese with English abstract). Zhou, Y.Y., Zhao, T.P., Xue, L.W., Wang, S.Y., 2009b. Geochemistry and origin of Neoarchean amphibolites in Songshan, Henan Province. Acta Petrologica Sinica 25 (11), 3043—3056 (in Chinese with English abstract).

Zhou, Y.Y., Zhao, T.P., Wang, S.Y., Hu, G.H., 2011. Geochronology and geochemistry of 2.5 to 2.4 Ga granitic plutons from the southern margin of the North China Craton: implications for a tectonic transition from arc to post-collisional setting. Gondwana Research 20, 171-183.