Placing Another Piece of the Tethyan Puzzle: The First Paleozoic Paleomagnetic Data From the South Qiangtang Block and Its Paleogeographic Implications

Wei, Bitian1; Cheng, Xin1; Domeier, Mathew2; Jiang, Nan1,3; Wu, Yiying1; Zhang, Weijie1,4; Wu, Ke1; Wang, Baofeng1; Xu, Pengxiang1; Xing, Longyun1; Zhang, Dongmeng1; Li, Teng1; Deng, Xiaohong1; Liu, Feifan1; Zhou, Yanan1; Wu, Hanning1

2022-10-01

10.1029/2022TC007355

TECTONICS   Impact Factor & Quartile

0278-7407

1944-9194

The origin and drift history of the South Qiangtang block (SQB) is critical to understanding the internal dimensions and kinematics of the late Paleozoic to early Mesozoic Tethyan realm and the subsequent evolution of the Qinghai-Tibet Plateau, but so far no paleomagnetic data constrain the SQB in Paleozoic time. Here we present a paleomagnetic study of the middle Permian volcanic and sedimentary rocks from the SQB. Well-defined high-temperature components of magnetization were isolated from 6 sites of tuffaceous sandstone and 9 sites of basalt, but their directional populations are distinct. On the basis of a conglomerate test and comparisons with younger paleomagnetic data, we argue the basalts preserve a primary magnetization, whereas the sandstones may have been remagnetized during the Triassic. The magnetic directions from the basalt indicate that the SQB was located at a latitude of 22.3 +/- 5.8 degrees S during the middle Permian. Together with existing paleomagnetic data from other Tethyan continental blocks, this new constraint reveals that during the middle Permian the Neo-Tethys Ocean spanned similar to 10-20 degrees of latitude and the Paleo-Tethys Ocean spanned similar to 50 degrees, but also that the latter was a composite ocean system which included at least two important branches. In further considering the geological records of the SQB, we propose the block rifted from the northern margin of Gondwana during opening of the Neo-Tethys in early Permian time, and then drifted rapidly northward until ultimately colliding with the North Qiangtang block and the southern margin of Laurasia during final closure of the Paleo-Tethys in the Triassic.

Tibetan Plateau South Qiangtang block Paleomagnetism Middle Permian Tethys Ocean

SCI ; EI

English

Others

National Natural Science Foundation of China["42274097","91855211","41774073","42074075"] ; Second Tibetan Plateau Scientific Expedition (STEP) program[2019QZKK0704] ; Research Council of Norway[250111]

Geochemistry & Geophysics

Geochemistry & Geophysics

WOS:000870493300001

AMER GEOPHYSICAL UNION

20224613113193

Geomagnetism ; Magnetization ; Oceanography ; Sandstone ; Volcanoes

Oceanography, General:471.1 ; Earth Magnetism and Terrestrial Electricity:481.3.2 ; Minerals:482.2 ; Seismology:484 ; Magnetism: Basic Concepts and Phenomena:701.2

GEOSCIENCES

Web of Science

1.Northwest Univ, State Key Lab Continental Dynam, Dept Geol, Xian, Peoples R China
2.Univ Oslo, Ctr Earth Evolut & Dynam CEED, Oslo, Norway
3.Yanan Univ, Sch Petr Engn & Environm Engn, Yanan, Peoples R China
4.Southern Univ Sci & Technol, Dept Ocean Sci & Engn, Ctr Marine Magnetism CM2, Shenzhen, Peoples R China

Wei, Bitian,Cheng, Xin,Domeier, Mathew,et al. Placing Another Piece of the Tethyan Puzzle: The First Paleozoic Paleomagnetic Data From the South Qiangtang Block and Its Paleogeographic Implications[J]. TECTONICS,2022,41(10).

Wei, Bitian.,Cheng, Xin.,Domeier, Mathew.,Jiang, Nan.,Wu, Yiying.,...&Wu, Hanning.(2022).Placing Another Piece of the Tethyan Puzzle: The First Paleozoic Paleomagnetic Data From the South Qiangtang Block and Its Paleogeographic Implications.TECTONICS,41(10).

Wei, Bitian,et al."Placing Another Piece of the Tethyan Puzzle: The First Paleozoic Paleomagnetic Data From the South Qiangtang Block and Its Paleogeographic Implications".TECTONICS 41.10(2022).