Paleogeographic evolution of a Carboniferous–Permian sea in the southernmost part of the Central Asian Orogenic Belt, NW China: Evidence from microfacies, provenance and paleobiogeography

Quantifying the Extent of the Paleo‐Asian Ocean During the Late Carboniferous to Early Permian

“…25°N paleolatitude narrowed the extent of the PAO. The scissors‐like closure of the PAO facilitated a diachronous mixing of the Tethyan and Boreal realm faunas during the Guadalupian (273–259 Ma) from west to east, as evidenced by the marine strata across the Beishan Orogenic Collage and Xilinhot block (Niu et al., 2021; Ren et al., 2020; Shen et al., 2006). Continental facies dominates the Lopingian (259–252 Ma) and extensive blending of the Angara and Cathaysian floras occurred in North China (Wu et al., 2021) and southeastern CAOB (Deng et al., 2009; Niu et al., 2021), prior to the final closure of the PAO at ca.…”

“…Permo-Carboniferous paleobiogeographical provinces are approximately distributed along lines of latitude and controlled by temperature. The boundary between brachiopods of the cold-water Boreal realm and warm-water Tethyan realm lies near the Hegenshan suture zone during the Late Carboniferous to Early Permian (Niu et al, 2021;Tian et al, 2016). The Xilinhot and North China blocks occupied lower latitudes and are characterized by Tethyan realm fauna and Cathaysian flora in contrast to the Boreal realm fauna Zhang, Huang, Zhao, Meert, et al (2018);6, Kovalenko (2010);7, Bazhenov et al (2016); 8, Kravchinsky, Cogné, et al (2002); 9, Kravchinsky, Sorokin, and Courtillot (2002).…”

Micro‐Blocks in NE Asia Amalgamated Into the Unified Amuria Block by ∼300 Ma: First Paleomagnetic Evidence From the Songliao Block, NE China

“…Paleontological and paleomagnetic evidence do show differences between the two blocks. The Upper Carboniferous limestones in the Xilinhot block developed tropical Tethyan phylloid algal‐bearing reefs (Yan et al., 2019) that are similar to North China but distinct from the Boreal‐realm characterizing the Mongolia and Songliao‐Jiamusi blocks (Niu et al., 2021; Shen et al., 2006; Tian et al., 2016; Ueno, 2006; Wang et al., 2013). The Xilinhot and North China blocks were located at low equatorial latitudes that are significantly different from the Songliao‐Jiamusi blocks that were located in the horse latitudes (∼33.2° ± 5.4°N; Figures 9 and 10; Table 2).…”

“…(2019) and Niu et al. (2021). Abbreviations are: NHS, Nenjiang‐Heihe Suture; ES, Erlianhot Suture; SMXB, South Mongolia‐Xing'an Belt.…”

“…Distributions of Hegenshan Ophiolites are shown in green. Distribution of flora and other fauna are after Shen et al (2006), Wang et al (2013), Yan et al (2019) and Niu et al (2021). Abbreviations are: NHS, Nenjiang-Heihe Suture; ES, Erlianhot Suture; SMXB, South Mongolia-Xing'an Belt.…”