|
Discussion |
1 1 Laboratory of Marginal Sea Geology, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou City 510640, P.R. China and Computational Geosciences Research Center, Central South University, Changsha City 410083, P.R. China
2 2 Laboratory of Marginal Sea Geology, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou City 510640, P.R. China
3 3 Laboratory of Marginal Sea Geology, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou City 510640, P.R. China
4 4 Geological Laboratories Center and Department of Geology, China University of Geosciences, Beijing 100083, P.R. China
5 5 The State Key Laboratory of Geological Processes and Mineral Resources and the Key Laboratory of Lithospheric Tectonics and Lithoprobing Technology of Ministry of Education, China University of Geosciences, Beijing 100083, P.R. China
6 6 Department of Earth Sciences, the University of Hong Kong, Hong Kong, P. R. China
7 7 The State Key Laboratory of Geological Processes and Mineral Resources and the Key Laboratory of Lithospheric Tectonics and Lithoprobing Technology of Ministry of Education, China University of Geosciences, Beijing 100083, P.R. China
8 8 The State Key Laboratory of Geological Processes and Mineral Resources and the Key Laboratory of Lithospheric Tectonics and Lithoprobing Technology of Ministry of Education, China University of Geosciences, Beijing 100083, P.R. China
9 9 Department of Earth Sciences, the University of Hong Kong, Hong Kong, P. R. China
 |
Introduction |
|---|
 Top Introduction References |
|---|
Citing of published work.
Yan et al. (2006a) cited many references (e.g. Lei et al. 1994; Niu et al. 1994; Yu & Zhang 1996; Chen 1999; Fu 1999; Meng et al. 2003) in support of their conclusions about early Triassic extension and formation of metamorphic core complexes, as well as Late Cretaceous normal faulting. In many cases, however, the cited references do not lend support to their interpretations. For example, the Du Shan granite and surrounding Archaean and Proterozoic metamorphic rocks (Yu & Zhang 1996) contain no evidence for extension or development of metamorphic core complex features, but instead record NE-trending, strike-slip ductile shearing, not top-to-the-SE extension. The Malanyu dome is an old metamorphic sequence (Chen 1999), and no one has previously interpreted it as an extensional dome associated with SE-directed extensional shear. Zhang et al. (1991) did not examine any aspect of the geology in the area of the so-called Yuerya metamorphic core complex. Furthermore, no dome has been identified here by any previous geologists; instead, it is a c. 175–174 Ma (U–Pb sensitive high-resolution ion microprobe ages, Luo et al. 2001) granitic sheet-like intrusion within the Mesoproterozoic stratigraphic sequence. As for the Fuping and Zanhuang metamorphic core complexes (Lei et al. 1994; Niu et al. 1994), no workers have ever suggested that they formed during early Mesozoic time. Several other examples referred to by Yan et al. (2006a), such as the Hefangkou and Hohhot metamorphic core complexes, formed after c. 140 Ma (Davis et al. 1996, 2002) instead of during the early Mesozoic as suggested by Yan et al. (2006a). Meng (2003) and Meng et al. (2003) did not suggest that the Cretaceous–Quaternary extension in north China was responsible for the uplift of the Taihang mountain range.
Stratigraphic sequences and related dioritic intrusions.
In the field, previous geologists have not reported any breccia and in fact there is no evidence for widespread ductile shearing either at the base of, or within, the Triassic, or within the Carboniferous–Permian successions. The deformation is compressional and only a few extensional fabrics such as S–C foliations have been recorded at some sites. The thrust and detachment zone between Triassic and Permian successions, or Triassic and Jurassic successions, can only be observed in a few areas in the Yanshan orogen and Western Hills of Beijing. Usually, the sedimentary successions from Carboniferous to Triassic are entirely conformable and the base of the Carboniferous is a well-known unconformity that is widespread in the north Chinese continent. The only hints of deformation on that surface are weak striations observed at some sites. There is no evidence for the early Triassic extension necessary to support the idea of a metamorphic core complex as proposed by Yan et al. (2006a).
Yan et al. (2006a) state: ‘The basement detachment fault is characterized by gouge and micro-breccia. Along the northern margin of the Fangshan pluton there is a 5–10 cm thick layer of gouge and micro-breccia at the top of the detachment fault (Figs 2 and 5a,b). Locally a sheet of schistose diorite along this fault (Fig. 5b) has a mylonitic foliation and is believed to be contemporaneous with the shear deformation (Song et al. 1996). This sheared diorite has a K–Ar amphibole age of 207 ± 2 Ma (Beijing Bureau of Geology and Mineral Resources & China University of Geosciences 1988), an age for the formation of the shear zone (Song et al. 1996).’
There are two main mistakes in their interpretation. (1) There is no fault gouge and micro-breccia exposed. In their figure 5a and b, the yellow rocks are weathered metasedimentary rocks that belong to the Xiamaling Formation (Upper Proterozoic), and not fault gouge. The caption for figure 5b does not correspond to the geological reality: from the lower to the upper part, the rocks exposed are undeformed diorite, Archaean rocks, and the folded Proterozoic Xiamaling Formation. There is no evidence in figure 5b to support their proposal for an extensional detachment. (2) No K–Ar amphibole age has ever been produced from the diorite at this locality to the knowledge of this author. During 1:50 000 geological mapping in 1985–1988, a dioritic rock was collected in the southern valley of Nanjiao, about 15 km west of the Fangshan granitic pluton, and analysed at a K–Ar laboratory in China (Beijing Bureau of Geology and Mineral Resources & China University of Geosciences 1988, p. 114; Shan et al. 1991, p. 53). It yielded a conventional K–Ar age of 207 Ma (no error quoted). Davis et al. (1998) dated the same diorite pluton at Nanjiao by the U–Pb method (zircon) and obtained an age of 128.4 ± 1.5 Ma. This U–Pb age is similar to that for the formation of the Fangshan granitic pluton (Davis et al. 1998, 2001). It is therefore incorrect that Yan et al. used the K–Ar age of 207 ± 2 Ma as very important evidence to support their model of early Mesozoic extension.
Structural fabrics and evolution.
None of the supposedly numerous detachment faults have been observed by previous workers, whether in the Fangshan pluton or surrounding it. To the north, west and SW of the Fangshan granitic pluton, stretching lineations are oriented at ESE 110° and correlative structural fabrics indicate detachment features. However, east of the Fangshan pluton, the stretching lineations correlate with north–south- to NE–SW-trending compressional fabrics that are influenced by the Fangshan pluton. The stretching lineations were not all formed at the same time or in a similar extensional tectonic environment. The ESE 110°-trending stretching lineations have not been influenced by the Fangshan granitic intrusion or its emplacement, which means that they formed after the intrusion. If the detachment deformation (D1) was earlier than the thrust faulting as suggested by Yan et al. (2006a), as well as formation of the Beiling syncline, and emplacement of the Fangshan granitic pluton, it is remarkable that such extensive compression and granitic intrusion did not modify the orientation of the detachment stretching lineation. To the west, north, south and SW of the Fangshan pluton, the foliations centrally dip to the direction of the pluton, but the stretching lineation is consistently oriented ESE 110°. The detachment, if it exists, must be later than the extensive NW-directed compression.
Can Yan et al. provide details of where it is possible to observe the overthrust covered by Jurassic strata? Similarly, where does the overthrust cut across the D1 detachment faults, and where does the Nandazai thrust fault cut through the detachment faults? With respect to the Changcao nappe, if the east–west-trending fault belongs to the hanging wall of the Changcao nappe, then the thrusting must be earlier than formation of the detachment (D1). Regionally, after ESE 110°-oriented extensional(?) deformation, there is no evidence for east–west-oriented thrusting. Whether in the west and east parts of the Yanshan orogenic belt, or other regional features such as the Inner Mongolia and Yanshan orogenic belts, south-vergent thrust faults formed prior to NE-trending extensional and strike-slip structures (Zhao et al. 1994; Davis et al. 1996; Wang 1996; Chen 1998). Pre- to early Jurassic stratigraphic sequences have been involved in the thrusting. Thus, the suggestion of Yan et al. (2006a) that thrust faults penetrated across the D1 detachment fault is completely not in accordance with the geological facts, nor is the suggestion that east–west-trending thrusts formed after ESE-directed extension.
Conclusion.
Published descriptions of stratigraphic sequences, structural fabrics and chronological data do not support the model of Yan et al. (2006a) for Early Triassic extension and development of the Fangshan metamorphic core complex. Thus, the relative structural stages and tectonic model proposed by Yan et al. (2006a) should be examined critically and investigated further before they can be used as a basis for understanding the Mesozoic tectonic evolution of north China.
Discussions with C. H. Zhang and T. F. Wan improved this comment.
7 March 2006
Dan-Ping Yan, Mei-Fu Zhou, Hong-Lin Song, Gen-Hou Wang & Min Sun reply: The Mesozoic extensional deformation structures described in our paper may have formed as part of a regional Mesozoic tectonic event, so we cited several other possible extensional structures, such as the Dushan metamorphic complex. This complex consists of a central granitic pluton, intruding Archaean to Proterozoic metamorphic rocks, which are separated from the cover sequence by a major detachment fault with prominent mylonitic fabrics indicating SE-directed movement (Fu 1999). Wang envisages these fabrics to be the result of NE-trending, ductile strike-slip shearing, but to our knowledge, no other workers have reached such a conclusion, including Yu & Zhang (1996), who were cited by Wang. The Yuerya (Fu 1999; Xiao et al. 2003), Malanyu (Chen 1999) and Fuping domes (Fu 1999) have been interpreted to be metamorphic core complexes by the respective researchers and we refer interested readers to the cited publications. We cited the Hefangkou and Hohhot metamorphic core complexes as late Mesozoic extensional features (D4) (Davis et al. 1996, 2002), not early Mesozoic.
Wang states that shearing and extensional features can only be observed locally in the Yanshan orogen and Western Hills of Beijing. We documented such features in the Fangshan dome but did not suggest that they would necessarily be widespread throughout ‘the north Chinese continent’. In detail, we described a 5–10 cm thick zone of fault gouge and micro-breccia at the top of the Fangshan detachment fault (fig. 5b), which Wang interprets to be weathered metasedimentary rocks of the Xiamaling Formation. However, his interpretation cannot explain (1) the occurrence of this band beneath the Xiamaling Formation, (2) the formation of the underlying mylonitic zone, or (3) why the Changcheng and Jixian Systems are missing, so that the Xiamaling Formation is separated from the Archaean rocks by a shear zone. The timing of the detachment is possibly constrained by a syntectonic diorite in the Nanjiao area, the western part of the extensional dome. This rock has a reported K–Ar age of 208 Ma. More importantly, this extensional event is well constrained by the geological relationships. The shearing fabrics are observed in the Early Triassic and older rocks, but not in Jurassic rocks or in the Fangshan pluton (c. 130 Ma). Therefore, the detachment formed after the early Triassic and prior to the Jurassic.
Wang states that the detachment faults of the Fangshan extensional dome have not been observed by previous workers, but such features were described by Shan et al. (1991) and Song et al. (1996). Wang also suggests that stretching lineations in rocks east of the Fangshan pluton correlate with north–south- to NE–SW-trending compressional fabrics. In fact, the Fangshan pluton is directly covered by Late Cretaceous–Quaternary sediments, so no country rocks are exposed to the east of the pluton. He further comments that the consistently oriented ESE 110° stretching lineations and the centrally dipping foliations in the country rocks mean that the detachment must be later than formation of the Beiling syncline and the emplacement of the Fangshan pluton. However, the ESE 110° lineation occurs only in the country rocks, not in the pluton, which indicates that the pluton is younger than the detachment. The centrally dipping foliations in the country rock either were formed during the intrusion or were modified from an earlier structure (we favour the latter interpretation). Our measurements of the foliation and lineation were collected in the Huangshandian, Gushankou and Ligezhuan areas, all well away from the pluton, and thus not affected by it.
As indicated in our figure 2, the Huangshandian overthrust is covered by the unconformity beneath the Jurassic strata. The exact location is on the southwestern slope of Beiling Mountain. The overthrust cuts across D1 structures in the small hill about 100 m east of Huangshandian village (our fig. 8). The detachment faults occur in both the hanging wall and footwall of the Changcao nappe (our fig. 2). Wang has apparently confused the ESE 110° extensional structure (D1) with the NE-trending extensional and strike-slip structures. Therefore, he argues that because the south-vergent thrusts in other areas of north China formed prior to the NE-trending structures, the D1 deformation must also be a later structure. In our paper, we provided field evidence that the D1 deformation is cut by the Huangshandian thrust (our fig. 8), hence the D1 deformation is evidently an older structure. Accordingly, Wang's comment that ‘thrust faults penetrated across the D1 is completely not in accordance with the geological facts’ is without foundation. We therefore conclude that our detailed geological investigations in the Fangshan area support an early extensional tectonic event, probably in the mid- to late Triassic, which was modified by later overthrusting.
11 July 2006
Yehua Shan, Faxiong Gong & Ge Lin write: Yan et al. (2006a) re-highlighted a conceptual model proposed previously by Wei & Song (1991), and modified by Song et al. (1996), that the Guangdi rock complex and D1 structures were produced by low-angle normal faulting during the middle and late Triassic. In contrast, these phenomena were generally interpreted by other workers as a result of intense tectono-magmatism during the late Jurassic and early Cretaceous. The model is, however, inconsistent with many aspects of the regional geology and structures. Our main points of criticism are as follows.
(1) Where are the synrift sediments? Conceptually, regional extension produces rift basin(s) (see Yan et al.'s fig. 10a) that will be coevally filled by rapidly accumulated sediments. In the study area (Hebei Bureau of Geology 1989), the only Triassic unit is the Shuangquan formation, which consists of silica-cemented, well-sorted quartz sandstone. It is widely present in the Western Hills (including the study area), with a fairly constant thickness of about 360 m. It has a disconformity with the underlying Permian Hongmiaoling formation. Only to the NE are exposed patches of the upper Triassic Xingshikou formation, of up to several tens of metres in thickness. The formation consists of lacustrine and fluvial fine-grained sandstone, siltstone and mudstone, and also has a disconformity with the underlying Shuangquan formation. In our opinion, it is not possible to relate either to synrift deposition.
(2) Intense deformation never took place in the Western Hills until the late Jurassic, as Wong (1927) first noticed. Very strangely, a vast majority of Yan et al.'s proposed normal faults are parallel or approximately parallel to the contact between two neighbouring formations with a great viscosity contrast. These faults should have an extremely low dip angle, provided the beds were horizontal during their nucleation and propagation. It seems highly unlikely that such low-angle normal faults or horizontal detachments could have accommodated significant amounts of extensional strain in the upper crust.
(3) Restoration of the outer rim of the forcefully emplaced Fangshan granodioritic body showed that nearly half of the room for subsequent inflation was obtained by pushing the country rock outwards (Shan et al. 2004). Possible mechanisms include dislocation, rotation, faulting, folding, homogeneous thinning, and so forth. In practice, such an effect must be discriminated in the nearby poly-deformed rocks so as to restore pre-existing deformation. This was not dealt with by Yan et al. (2006a) and others.
(4) D1 deformation was associated with a low-grade and locally medium-grade regional metamorphism in the southern Western Hills (Hebei Bureau of Geology 1989). Involved in the metamorphism were both the platformal layer and lower Jurassic sediments, in which chloritoid is observed in (meta)sedimentary rocks and weathered basalt. This indicates a younger age for the regional metamorphism, which seems not to support their model.
10 May 2006
Dan-Ping Yan, Mei-Fu Zhou, Hong-Lin Song, Gen-Hou Wang & Min Sun reply: Shan et al. raise several concerns regarding our model for the Fangshan core complex, west of Beijing (Yan et al. 2006a). Their criticism is largely based on incomplete information.
Sedimentary basins associated with Late Triassic extension and D1.
Triassic strata crop out mainly in the western part of the North China Block, such as in the Ordos basin (Ritts et al. 2004). In the eastern part of the North China Block, the origin of sparse outcrops of Triassic strata is poorly understood (Hebei Bureau of Geology 1989; Liaoning Bureau of Geology & Mineral Resources 1989). Recently, Yan et al. (2006b) identified late Triassic (200–230 Ma) detrital zircons from the Lower Jurassic Beipiao Formation in the eastern segment of the Yanshan mountain range and inferred large uplift and erosion of the late Triassic basins in the Yanshan area. The Triassic Xingshikou Formation within the Yanshan area is composed of rounded conglomerate (Hebei Bureau of Geology 1989; Liaoning Bureau of Geology & Mineral Resources 1989). It is also notable that rift basins coeval with regional extension may not necessarily be filled with rapidly accumulated sediments.
Pre-Jurassic deformation.
Geological investigation has identified a mid- to late Triassic deformation throughout the Yanshan area (Indosinian in China). However, this early deformation was immediately overprinted by much more intense and widely distributed late Mesozoic deformation, metamorphism and magmatism (fig. 1) (Hebei Bureau of Geology 1989; Liaoning Bureau of Geology & Mineral Resources 1989). The late Mesozoic modification most probably overprinted much of the Triassic deformation.
Low-angle normal faults can thin and/or remove strata on a regional scale. The existence of these faults is documented by mylonitic rocks and kinematic features on the faults as described by Yan et al. (2006a). Although very high strains were not documented in either the basement detachment or the hanging wall, the Fangshan extensional dome is similar to the Jianglang tectonic dome described by Yan et al. (2003), but slightly different from metamorphic core complexes in the US Cordillera (e.g. Lister & Davis 1989). A fluid crustal layer (see Wernicke 1990), or a ductilely deformed slab, in the Fangshan area, separates the metamorphic core from the brittle cover. The Fangshan extensional tectonic dome has a three-layer configuration (Yan et al. 2003).
Relationship of the deformation in the Fangshan pluton and peripheral areas.
Shan et al. (2004) proposed a ballooning model for the ascent and emplacement of the Fangshan pluton. Although the technique involving continuous restoration is acceptable, it is not appropriate to the Fangshan pluton. Shan et al. (2004) divided the Fangshan pluton into three zones: the marginal, transitional and central zones. However, the intrusion shows strong solid-state deformation only in the northwestern part and only very weak deformation in the southeastern part. Solid-state deformation can occur only after the crystallization of magma, and thus cannot be used to estimate the room for the emplacement of magma. Shan et al. (2004) have tried to determine how space for the pluton was created during the early stage of intrusion (marginal zone). They used the dark dioritic enclave ratios to calculate the strain. However, such a calculation is not valid, because the strain should include solid-state strain (RS), magmatic strain (Rfmag) and primary elliptical shapes (Rp) of the enclaves (Tobisch & Williams 1998). The ductile deformation and thinning or removal of strata in the vicinity of the pluton also occurred in Gushankou (fig. 2) and elsewhere far from the pluton. Thus the strain in the Fangshan area did not result from the intrusion.
Regional metamorphic grade and geochronological constraint.
The Proterozoic to Triassic strata in the Fangshan area were metamorphosed under low to medium greenschist facies, whereas the Jurassic strata are only locally metamorphosed along their contact with the intrusion. Clearly, it is crucial to date the regional metamorphism. However, it is almost impossible to obtain reliable dates because of intense, late Mesozoic overprinting that may have completely reset the minerals. Thus, the geological relationships provide the only reliable means of determining age constraints. Only Carboniferous strata near the pluton contain chloritoid.
11 July 2006
|
References |
|---|
|
TopIntroductionReferences |
|---|
Beijing Bureau of Geology and Mineral Resources & China University of Geosciences 1988. [Regional and Mineral Resource Geology of the Zhoukoudian area.] Unpublished report [in Chinese].
Chen, A., 1998. Geometric and kinematic evolution of basement-core structures: intraplate orogenesis within the Yanshan Orogen, northern China. Tectono-physics, 292, 17–42.[CrossRef][Web of Science][GeoRef]
Chen, X.B., 1999. Preliminary knowledge on control of Malanyu metamorphic core complex on metallization. Geological Exploration Non-Ferrous Metals, 8, 311–324 [in Chinese with English abstract].
Davis, G.A., Qian, X., Zheng, Y. , ET AL., 1996. Mesozoic deformation and plutonism in the Yunmeng Shan: a Chinese metamorphic core complex north of Beijing, China. In: Yin, A. & Harrison, T.M. (eds) The Tectonic Evolution of Asia. Cambridge University Press, Cambridge, 253–280.
Davis, G.A., Wang, C., Zheng, Y., Zhang, J., Zhang, C. & Gehrels, G.E. 1998. The enigmatic Yinshan fold- and thrust-belt of northern China: new views on its intraplate contractional styles. Geology, 26, 43–46.
Davis, G.A., Zheng, Y.D., Wang, C., Darby, B.J., Zhang, C. & Gehrels, G. 2001. Mesozoic tectonic evolution of the Yanshan fold and thrust belt, with emphasis on Hebei and Liaoning provinces, northern China. Geological Society of America, Memoirs, 194, 171–192.
Davis, G.A., Darby, B.J., Zheng, Y.D. & Spell, T.L. 2002. Geometric and temporal evolution of an extensional detachment fault, Hohhot metamorphic core complex, Inner Mongolia, China. Geology, 30, 1003–1006.
Fu, Z.Y., 1999. The metamorphic core complexes in Hebei, China. Geology and Mineral Resources Research, 14, 10–16 [in Chinese with English abstract].
Hebei Bureau of Geology 1989. Regional Geology of Hebei Province. Ministry of Geology and Mineral Resources, Geological Memoirs, Series 1, 5, [in Chinese with English abstract].
Lei, S.H., Hu, S.J., Zhao, Z.Y., Jiang, X.W. & Wang, S.D. 1994. Structures and mechanisms of the Fuping and Zanfang metamorphic core complexes in Hebei province. Journal of Hebei Geological College, 17, 54–64 [in Chinese with English abstract].
Liaoning Bureau of Geology and Mineral Resources 1989. Regional Geology of Liaoning Province. Ministry of Geology and Mineral Resources, Geological Memoirs, Series 1, 14, [in Chinese with English abstract].
Lister, G.S. & Davis, G.A. 1989. The origin of metamorphic core complexes and detachment faults formed during Tertiary continental extension in the northern Colorado River region, USA. Journal of Structural Geology, 11, 65–94.[CrossRef][Web of Science][GeoRef]
Luo, Z.K., Qiu, Y.S., Guan, K., Miao, L.C., Qiu, Y.M., McNaughton, N.J. & Groves, D.I. 2001. SHRIMP U–Pb dating on zircon from Yu'erya and Niuxinshan granite intrusions in eastern Hebei Province. Bulletin of Mineralogy, Petrology and Geochemistry, 20, 278–285 [in Chinese with English abstract].
Meng, Q.R., 2003. What drove late Mesozoic extension of the northern China–Mongolia tract? Tectonophysics, 369, 155–174.[CrossRef][Web of Science][GeoRef]
Meng, Q.R., Hu, J.M., Jin, J.Q., Zhang, Y. & Xu, D.F. 2003. Tectonics of the late Mesozoic wide extensional basin system in the China–Mongolia border region. Basin Research, 15, 397–415.[CrossRef][Web of Science][GeoRef]
Niu, S.G., Sun, E.Q., Xu, Z.S., Luo, D.W., Shao, Z.G. & Li, R. 1994. [Fuping and Zanfang domes are Mesozoic to Cenozoic metamorphic core complexes within Taihang Mountains.]. Geological Science and Technology Information, 13, 15–16 [in Chinese].
Ritts, B.D., Hanson, A.D., Darby, B.J., Nanson, L. & Berry, A. 2004. Sedimentary record of Triassic intraplate extension in North China: evidence from the nonmarine NW Ordos Basin, Helan Shan and Zhuozi Shan. Tectonophysics, 386, 177–202.[CrossRef][Web of Science][GeoRef]
Shan, W., Song, H., Fu, Z. & Ren, J. 1991 [. Principles, Methods and Practices of Structural Analysis.]. China University of Geosciences Press, Wuhan, [in Chinese].
Shan, Y., Lin, G., Li, Z. & Suen, H. 2004. Continuous construction of the reverse displacement gradients and its application to granodoritic pluton in central North China. Journal of Structural Geology, 26, 71–85.[CrossRef][Web of Science][GeoRef]
Song, H., Fu, Z. & Yan, D. 1996. Extensional tectonics and metamorphic core complex of Western Hills. In:. Field Trip Guide for 30 IGC, Beijing.T210, 1–8.
Tobisch, O.T. & Williams, Q. 1998. Use of microgranitoid enclaves as solid state strain markers in deformed granitic rock: an evaluation. Journal of Structural Geology, 20, 727–743.[CrossRef][Web of Science][GeoRef]
Wang, Y., 1996. Tectonic evolutional process of Inner Mongolia–Yanshan orogenic belt in eastern China during the late Palaeozoic–Mesozoic. Geological Publishing House, Beijing, [in Chinese with English abstract].
Wei, B. & Song, H. 1991. Fangshan metamorphic core complex, Beijing. In: Zhang, J. & Shan, W. (eds) Study of Geology in Western Hills of Beijing. University of Geosciences Press, Wuhan, 42–47 [in Chinese with English abstracts].
Wernicke, B., 1990. The fluid crustal layer and its implications for continental dynamics. In: Salisbury, M.H. & Fountain, D.M. (eds) Exposed Cross-sections of the Continental Crust. Kluwer, Dordrecht, 509–544.
Wong, H., 1927. Crustal movement and igneous activities in eastern China since Mesozoic time. Bulletin of Geological Society of China, 6, 9–36.
Xiao, W.J., Windley, B.F., Hao, J. & Zhai, M.G. 2003. Accretion leading to collision and the Permian Solonker suture, Inner Mongolia, China: termination of the central Asian orogenic belt. Tectonics, 22, 1–20.
Yan, D.P., Zhou, M.F., Song, H.L. & Fu, Z.R. 2003. Structure style and tectonic significance of the Jianglang dome in the eastern margin of the Tibetan plateau, China. Journal of Structural Geology, 25, 765–779.[CrossRef][Web of Science][GeoRef]
Yan, D.P., Zhou, M.F., Song, H.L., Wang, G.H. & Sun, M. 2006a. Mesozoic extensional structures of the Fangshan tectonic dome and their subsequent reworking during collisional accretion of the North China Block. Journal of the Geological Society, London, 163, 127–142.
Yan, Y., Lin, G., Xia, B., Li, Z., Cui, J. & Yuan, G. 2006b. U–Pb dating of single detrital zircon grains from Mesozoic sandstone in the Beipiao Basin in the eastern Yan-Liao Orogenic Belt, China: provenance and correlation of tectonic evolution. Journal of Asian Earth Sciences, 26, 669–681.[CrossRef][Web of Science][GeoRef]
Yu, W.L. & Zhang, J.M. 1996. Discussion on the genesis of Dushan granite in eastern Hebei, Northern China. Journal of Mineral Petrology, 16, 1–7 [in Chinese with English abstract].
Zhang, Q.S., Yang, Z.S., Gao, D.Y. & Ren, H.M. 1991 [. Geology and gold deposit in the high-grade metamorphic area of Jinchangyu, Eastern Hebei.]. Geological Publishing House, Beijing, [in Chinese].
Zhao, Y., Yang, Z.Y. & Ma, X.H. 1994. Geotectonic transition from paleoasian system and paleotethyan system to paleopacific active continental margin in eastern Asia. Scientia Geologica Sinica, 29, 105–119 [in Chinese with English abstract].
| ||||||||||||||||||||||||||||||||||||||||||||||||||||||||
