Earth-Science Reviews 186 (2018) 262–286 Contents lists available at ScienceDirect Earth-Science Reviews journal homepage: www.elsevier.com/locate/earscirev Geological reconstructions of the East Asian blocks: From the breakup of T Rodinia to the assembly of Pangea ⁎ Guochun Zhaoa,b, , Yuejun Wangc, Baochun Huangd, Yunpeng Dongb, Sanzhong Lie, Guowei Zhangb, Shan Yub a Department of Earth Sciences, University of Hong Kong, Pokfulam Road, Hong Kong b State Key Laboratory of Continental Dynamics, Department of Geology, Northwest University, Northern Taibai Str. 229, Xi'an 710069, China c Guangdong Provincal Key Lab of Geodynamics and Geohazards, School of Earth Sciences and Engineering, Sun Yat-sen University, Guangzhou 510275, China d Key Laboratory of Orogenic Belt and Crust Evolution, Ministry of Education, School of Earth and Space Sciences, Peking University, Beijing 100871, China e Key Lab of Submarine Geosciences and Prospecting Techniques, Ministry of Education, College of Marine Geosciences, Ocean University of China, Qingdao 266100, China ARTICLE INFO ABSTRACT Keywords: Pangea is the youngest supercontinent in Earth's history and its main body formed by assembly of Gondwana and Supercontinent Laurasia about 300–250 Ma ago. As supported by voluminous evidence from reliable geological, paleomagnetic Pangea and paleontological data, configurations of major continental blocks in Pangea have been widely accepted. East Asia However, controversy has long surrounded the reconstructions of East Asian blocks in Pangea. To determine Assembly whether or not the East Asian blocks were assembled to join Pangea before its breakup, we carried out geological Breakup and paleomagnetic investigations on East Asian blocks and associated orogenic belts, supported by a NSFC Major Reconstruction Program entitle “Reconstructions of East Asian blocks in Pangea”. Our results indicate that the breakup of Rodinia around 750 Ma ago led to the opening of the Proto-Tethys and Paleo-Asian oceans in East Asia, with the former separating the South China, North China, Alex Qaidam and Tarim blocks from other East Asian blocks at the margins of Australia and India, whereas the Paleo-Asian Ocean existed between the East Asian blocks and Siberia-Eastern Europe. The Proto-Tethys Ocean closed in the early Paleozoic (500–420 Ma), leading to the collision of South China, North China, Alex, Qaidam and Tarim with other East Asian blocks at the northern margin of Gondwana. The subduction of the Paleo-Asian Ocean formed the Central Asian Orogenic Belt, the largest accretionary orogen in Earth's history, and its closure was diachronous, with its western, central and eastern segments closing at 310–280 Ma, 280–265 Ma and 260–245 Ma, respectively, leading the Tarim, Alex and North China blocks to join Eastern Europe-Siberia as part of Pangea. During the early Devonian (420–380 ma), the East Paleo-Tethys Ocean opened with two branches, of which the north branch is called the Mianlue Ocean that separated the Tarim-Qaidam-Central Qilian-Alex and North China blocks in the north from North Qiangtang-Indochina-South China in the south, and the south branch is the stricto sensu East Paleo-Tethys Ocean that separated North Qiangtang-Indochina-South China from the Sibumasu and South Qiangtang-Lhasa blocks at the northern margin of Gondwana. In the Triassic, the East Paleo-Tethys Ocean (stricto sensu) closed along the Longmu Co – Shuanghu – Changning – Menglian – Inthanon belt, leading to the collision of North Qiangtang- Indochina-South China with Sibumasu and South Qiangtang-Lhasa, forming a single southern continent, which then collided with the Tarim-Qaidam-Central Qilian-Alex and North China blocks to form a coherent East Asian continent that had become part of Pangea by 220 Ma, when the Mianlue Ocean closed, leading to the formation of the E-W-trending Central China Orogenic System. 1. Introduction crust, or subduct beneath each other to create new crust and finally collide to generate orogenic belts. Some rigid plates (like the Pacific According to modern plate tectonics, Earth's surface consists of a plate) consist exclusively of oceanic crust, but most plates comprise number of rigid plates that either drift apart to create new oceanic both continental and oceanic crusts like the Eurasian plate. A ⁎ Corresponding author at: Department of Earth Sciences, James Lee Science Building, The University of Hong Kong, Pokfulam Road, Hong Kong. E-mail address: [email protected] (G. Zhao). https://doi.org/10.1016/j.earscirev.2018.10.003 Available online 06 October 2018 0012-8252/ © 2018 Elsevier B.V. All rights reserved. G. Zhao et al. Earth-Science Reviews 186 (2018) 262–286 supercontinent forms when all oceanic crust is consumed through plate the Early Paleozoic orogenic belts, Central Asian Orogenic Belt, Central subduction and nearly all continental blocks on Earth collide each other China Orogenic System and Paleo-Tethys Belt, which resulted from the and coalesce into a single landmass. Theoretically, such a probability subduction and closure of the Proto-Tethys Ocean, Paleo-Asian Ocean, that all continental blocks on Earth move together to form a single north and south branches of Paleo-Tethys Ocean, respectively. The landmass should be extremely low, which may be a reason why only a program has also obtained new Late Paleozoic to Triassic paleomag- few supercontinents formed in Earth's ~4.57 Ga long history, including netic data for the Indochina, Sibumasu, Lhasa, Qiangtang and Qaidam Columbia (Nuna) forming about 1.8 Ga ago (Rogers and Santosh, 2002; blocks and those micro-continental blocks within the eastern segment Zhao et al., 2002, 2004), Rodinia about 1.0 Ga ago (Dalziel, 1991; of the Central Asian Orogenic Belt (Yi et al., 2015; Zhao et al., 2015; Hoffman, 1991; Moores, 1991; Torsvik, 2003; Goodge et al., 2008; Li Yan et al., 2016; Huang et al., 2018 and references wherein). The et al., 2008a), and Pangea about 300–250 Ma ago (Wegener, 1912; geological and paleomagnetic data obtained from this NSFC Major Smith and Livermore, 1991; Murphy and Nance, 2008; Stampfli et al., Program, combined with those from previous studies, have led us to 2013). Recently, some people argue for an end-Archean (~2.5 Ga) su- conclude that the East Asian blocks had amalgamated to form a single percontinent (e.g. Knoreland), though global-scale end-Archean colli- continent that was added to the main body of the Pangea Super- sional events leading to the assembly of such a supercontinent have not continent by ~220 Ma. These geological data combined with available been recognized. No matter whether or not such an end-Archean su- paleomagnetic data also enable us to have reconstructed major geolo- percontinent existed, it seems that every other 700–800 Ma, nearly all gical events that the East Asian blocks experienced from the breakup of continental blocks on Earth's surface met together to form a super- Rodinia to the assembly of Pangea and the possible positions of the East continent, whose geodynamic mechanism still remains as an enigma to Asian blocks in Pangea, which are reflected in ten summary and review earth scientists. papers presented in this special issue (Cawood et al., 2018; Dong et al., Of recognized supercontinents in Earth's history, Pangea is the 2018a; Han and Zhao, 2018; Eizenhöfer and Zhao, 2018; Huang et al., youngest one that was first proposed by Alfred Wegener (1912) at the 2018; Li et al., 2018; Wang et al., 2018; Xiao et al., 2018; Zhao et al., beginning of the last century on the basis of his continental drift hy- 2018; Zhou et al., 2018a, b). It deserves mentioning here that the re- pothesis. Although Wegener's continental hypothesis was initially re- construction maps presented in this contribution are mainly based on garded ridiculous as he did not well explain what's a plausible driving geological reconstructions though in most cases they are consistent with force for the drifting of continents across ocean beds, but half a century paleomagnetic reconstructions, especially for those for the Paleozoic later it became, in a modified form, fully acknowledged and now has (e.g. Huang et al., 2018). The aim of this contribution is to present a been incorporated into the modern theory of plate tectonics. As sup- series of time slice reconstructions and summarize geological evidence ported by voluminous evidence from geological, paleomagnetic and for these reconstructions, with emphasis on the spatiotemporal evolu- paleontological data, the configurations of major continental blocks tion of the East Asian blocks from Rodinia to Pangea. Appendix I is a (e.g. Australia, Antarctica, India, Africa, South America, North America, powerpoint presentation with an animation showing major geological Greenland, Baltica, Siberia, etc.) in Pangea have been widely accepted events that the East Asian blocks experienced from the breakup of (Muttoni et al., 2003, 2009). However, controversy has long sur- Rodinia to the assembly of Pangea based on geological reconstructions rounded the reconstructions of the East Asian blocks in Pangea, in- presented in this contribution. cluding North China, South China (Yangtze and Cathaysia), Tarim, Qaidam, Central Qilian, North Qinling, South Qinling, North Qiang- 2. Positions of some East Asian blocks in Rodinia tang, South Qiangtang-Lhasa, Indochina (Annamia), Sibumasu, etc. (Fig. 1). A large number of models have been proposed for re- Rodinia is a Meso-Neoproterozoic supercontinent that was as- constructions of these East Asian blocks and also their relations to sembled 1.1–0.9 billion years ago and broke up 750–600 million years Pangea (Zhao and Coe, 1987; Ren et al., 1990, 2000; Metcalfe, 1994, ago (McMenamin and MacMenamin, 1990; Dalziel, 1991, 1997; 1996; Metcafe, 2009; Metcalfe, 2011a; Metcalfe, 2013a; Li et al., 1995a; Hoffman, 1991; Moores, 1991; Meert and Torsvik, 2003; Torsvik, 2003; b; Li et al., 1996; Şengör and Natal'in, 1996; Yin and Nie, 1996; Li, Goodge et al., 2008; Li et al., 2008a; Zheng et al., 2008a, 2008b).