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Constraining Assembly Time of Some Blocks on Eastern Margin Of Earth-Science Reviews 207 (2020) 103215 Contents lists available at ScienceDirect Earth-Science Reviews journal homepage: www.elsevier.com/locate/earscirev Constraining assembly time of some blocks on eastern margin of Pangea T using Permo-Triassic non-marine tetrapod records ⁎ Jun Liua,b,c, , Jian Yia,c, Jian-Ye Chena a Key Laboratory of Vertebrate Evolution and Human Origins of Chinese Academy of Sciences, Institute of Vertebrate Paleontology and Paleoanthropology, Chinese Academy of Sciences, Beijing 100044, China b CAS Center for Excellence in Life and Paleoenvironment, Beijing 100044, China c College of Earth and Planetary Sciences, University of Chinese Academy of Sciences, Beijing 100049, China ARTICLE INFO ABSTRACT Keywords: The supercontinent Pangea was mainly formed during the Permian, but when it reached maximum land is Pangea unsure because the configuration of the East Asian blocks during the Permo-Triassic is still highly debated. Fossil East Asia tetrapods provide one of the best calibrations to the time of connection between continents, but the data of Assembly Permian Permo-Triassic tetrapods have rarely been applied in the previous reconstructions. Here we review the oldest Triassic records of non-marine tetrapods on the East Asia blocks and use them to discuss the timing of connection Non-marine tetrapods between continents during the Permian and Triassic. The distribution of Seymouriamorpha shows the Kazakhstanian was connected to the Baltica by land from the Cisuralian. The diverse Dashankou Fauna indicates that the Alxa Block amalgamated to Pangea at least in the Guadalupian (older than 266 Ma). The questionable footprints and late Permian dicynodont assemblage from the North China show the North China Craton may have been connected to the main part of Pangea from the Guadalupian, and became part of Pangea at least by 256 Ma. The late Permian Laotian tetrapods support the hypothesis that the South China Block already collided with the North China and the Indochina blocks by the end of the Permian, and there was a land route for the migration of non-marine tetrapods. 1. Introduction Permian mass extinction (Faure et al., 1995). The configuration of major continental blocks in Pangea has been widely accepted although the Paleogeographic maps, showing ancient mountain ranges, shor- connection time of Kazakhstania and Baltica varies (Metcalfe, 2013; elines, shallow seas and deep ocean basins, are widely used in paleo- Muttoni et al., 2009; Torsvik and Cocks, 2017), but that of the East Asian climatology, plate tectonic reconstructions, paleobiogeography, re- blocks in Pangea is still highly debated (e.g., Domeier and Torsvik, 2014; source exploration and geodynamics (Cao et al., 2017). These maps are Metcalfe, 2011; Metcalfe, 2013; Stampfli et al., 2013; Torsvik and Cocks, reconstructed traditionally by using paleomagnetism, biogeography 2017; Zhao et al., 2018). The East Asia blocks include many blocks and and faunal links, abiotic links, and continent–ocean configurations terranes, but in this paper we mainly discuss those with Permo-Triassic (Ross, 1999). Starting from Stampfli and Borel (2002), the plate model non-marine tetrapod fossils: North China (NCB, also known as the Sino- accounting of plate kinematics and geodynamic forces was applied to Korean Block), South China (SCB, including Yangtze and Cathaysia), the early Mesozoic and Paleozoic reconstructions (Domeier and Tarim, Alxa (Alashan)-Hexi corridor-Qilian (AHQ), and Indochina (ICB, Torsvik, 2014). Because some fundamental data are absent and some also known as Annamia) (Fig. 1). are conflicting, different teams often produce different maps forthe In previous reconstructions, Pangea reached its maximum land by the same age, e.g., Permo-Triassic (Huang et al., 2018; Li and Powell, 2001; Late Triassic, and the East Asian blocks did not amalgamate to form part Metcalfe, 2011; Scotese and McKerrow, 1990; Sengör, 1987; Shi, 2006; of Pangea by that time in some paleogeographical maps (Domeier and Stampfli and Borel, 2002; Torsvik and Cocks, 2017; Zhao et al., 2018). Torsvik, 2014; Golonka, 2007; Metcalfe, 2011; Metcalfe, 2013; Scotese, During this period, the continents and terranes amalgamated as a 2004; Torsvik and Cocks, 2017). Because the process and timing of some supercontinent, Pangaea. The consolidation of Pangea had a deep impact key events are still unclear, the paleogeographical maps vary in the po- on ecosystems, e.g., the formation of coal (Nelsen et al., 2016), the end- sitions of many blocks, especially for the East Asian blocks. ⁎ Corresponding author at: Institute of Vertebrate Paleontology and Paleoanthropology, Chinese Academy of Sciences, Beijing 100044, China. E-mail address: [email protected] (J. Liu). https://doi.org/10.1016/j.earscirev.2020.103215 Received 19 January 2020; Received in revised form 5 May 2020; Accepted 10 May 2020 Available online 01 June 2020 0012-8252/ © 2020 Elsevier B.V. All rights reserved. J. Liu, et al. Earth-Science Reviews 207 (2020) 103215 Fig. 1. Orthographic projection of the present day Eastern Asia and adjacent areas showing the boundaries of some Paleozoic blocks and terranes and some Permian tetrapod localities. The blocks and terrane boundaries are modified from Domeier (2018) and Xiao et al. (2018).. Traditionally, the biogeographic data were applied to determine During the early Carboniferous, tetrapods were known only in and test paleogeographic linkages between continental blocks (Cao Euramerica and Australia, but may have been distributed worldwide et al., 2017; McKerrow and Cocks, 1986; Shi, 2006). The timing of through equatorial regions (Thulborn et al., 1996). However, no Car- collage is generally inferred from sedimentary and metamorphic rock boniferous tetrapods are currently known from the NCB, SCB and ICB records. To supplement the knowledge, fossil tetrapods provide one of (Carroll, 2009 and see the data below), which may due to the isolation the best calibrations to the time of connection between continents. In of these blocks from Laurussia and Gondwana although they lay in this paper, we summarize the current Permian and Triassic tetrapod equatorial region (Metcalfe, 2013; Torsvik and Cocks, 2017). Amniotes records of East Asia, use them to support the assembly of the East Asian appeared no later than the Late Carboniferous (~315 Ma) from Nova blocks with the Pangea and calibrate the times of assembly. The results Scotia, Canada (Carroll, 1964). During that time, the NCB, SCB, and ICB can be used to test and improve the reconstructed maps mainly based were isolated from Pangea, so the terrestrial tetrapods in these regions on the geological and paleomagnetic data. should have migrated from Pangea. As mentioned above, if the animals reached new continents after the blocks had collided and there was a land bridge, the fossil age can be 2. Method used as a time calibration of the land connection and the collision. However, if the animals had sweepstakes routes such as rafting on trees, In one of his most celebrated papers, G. G. Simpson (1940) dis- fossil calibration for collision is compromised. A good criterion for the cussed how some mammal species had crossed regions that are now land bridge is that it does tend to transport integrated faunules impassable to them. He proposed land bridges and sweepstakes routes (Simpson, 1940). Another criterion is that the large-sized terrestrial as possible dispersal mechanisms. The rafting was used to explain how animals (e.g., skull length greater than 25 cm) passed the barrier and mammals migrated from Africa to Madagascar. For ancient groups, appeared on a new continent. This kind of animal is too heavy to have a their distribution can only be understood in the light of plate tectonics. sweepstakes process. However, sometimes large animals can swim for The movement of plates changed the distribution of the tetrapods, ~100 km to reach isolated islands. Examples can be seen from living especially terrestrial tetrapods (Hedges et al., 1996). Most terrestrial and fossil mammals, e.g., Pliometanastes had arrived North America species can migrate from one block to another only when two blocks about 9 million years ago, prior to formation of the Isthmus of Panama collide and become connected. For example, some Gondwanan lineages about 2.7 million years ago, by island-hopping across the Central dispersed into Asia when peninsular India collided with the Asian plate American Seaway (Tedford et al., 2004). So the second criterion should (Karanth, 2006). However, the sweepstakes process maybe a common be used in cautious. mechanism for small animals if there were suitable ocean currents and wind (Ali and Huber, 2010; Hawlitschek et al., 2016; Houle, 1998). 2 J. Liu, et al. Earth-Science Reviews 207 (2020) 103215 3. Review of the Permian and Triassic non-marine tetrapods Lucaogou Formation of Urumqia, Xinjiang, China (Zhang et al., 1984), records of East Asia therefore, is the oldest Permian tetrapod in this region. The Lucaogou Formation in Xinjiang was regarded as upper Permian or later Gufeng In East Asia, Permian and Triassic tetrapods were reported only stage (Guadalupian), but it should be correlated to the Sakmarian to from China, Mongolia, Laos and Thailand (Buffetaut et al., 2009a; Artinskian (Cisuralian) based on an IDTIMS age of 281.39 ± 0.10 Ma Gubin and Sinitza, 1993; Li et al., 2008). from the top of the Hongyanchi For mation and Gzhelian age (~300 Ma) from the lower part of the Daheyan Formation (Yang et al., 3.1. North and South foothills of the Bogda Mountain 2010), therefore, the age of Urumqia liudaowanensis could be older than 285 Ma (Fig. 2). No fossil tetrapod is known between the Lucaogou The Permo-Triassic deposits are well exposed on two sides of the Formation and the top of the Quanzijie Formation, which produced a Bogda Mountain, within the Junggar Basin and Turpan-Hami Basin. dicynodont Kunpania scopulusa (Sun, 1978). The taxonomical status of The tetrapods appeared in the Lucaogou, Quanzijie, Wutonggou, this species has been highly debated (Kammerer et al., 2011; Lucas, Guodikeng, Jiucaiyuan, Shaofanggou, Karamay, and Huangshanjie 1998, 2005), and an ongoing study may shed light on this question.
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