气候变化领域集成服务门户(CCPortal): Paleomagnetism of Middle Triassic Lavas From Northern Qiangtang (Tibet): Constraints on the Closure of the Paleo-Tethys Ocean

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DOI	10.1029/2019JB017804
	Paleomagnetism of Middle Triassic Lavas From Northern Qiangtang (Tibet): Constraints on the Closure of the Paleo-Tethys Ocean
	Song, Peiping; Ding, Lin; Lippert, Peter C.; Li, Zhenyu; Zhang, Liyun; Xie, Jing
通讯作者	Song, PP (通讯作者)
发表日期	2020
ISSN	2169-9313
EISSN	2169-9356
卷号	125 期号:2
英文摘要	We present results from a paleomagnetic study of Middle Triassic lavas (similar to 242-240 Ma) from the northern Qiangtang block to improve our understanding of the timing and kinematics of the closure of the eastern Paleo-Tethys Ocean. Characteristic remanent magnetization directions carried by magnetite and hematite formed during high-temperature oxidation during initial cooling of the lavas are successfully isolated by progressive thermal and alternating field demagnetizations. We bin 28 site mean directions into 20 independent direction groups that pass the fold test, average secular variation, and show no rock magnetic or petrographic evidence of weathering. These data establish the first lava-based paleomagnetic pole of Middle Triassic age for the northern Qiangtang block (62.2 degrees N, 196.4 degrees E, A(95) = 5.6 degrees). We compare this pole to coeval poles from the North China Block and Tarim and estimate that the remnant Paleo-Tethys or IIoh-Xil-Songpan-Ganzi Ocean could have been up to 700 km at similar to 240 Ma. A comparison of the Triassic latitudinal history between the northern Qiangtang block and the North China Block and Tarim shows that the closure of the Paleo-Tethys Ocean most likely occurred during the latest Triassic. Our review of published Permian-Triassic poles from the northern Qiangtang block show that the average south-north plate velocity of the terrane decelerated from similar to 8.5 cm/yr during similar to 300-240 Ma to similar to 3.6 cm/yr during similar to 240-210 Ma. We suggest that an arc-continent collision between the northern Qiangtang block and a Palco-Tethys or Yidun arc around or before 240 Ma contributed to this change in plate velocity.
关键词	TECTONIC EVOLUTION VOLCANIC-ROCKS PERMIAN ROCKS YIDUN ARC FOLD TEST POLAR WANDER SOUTH CHINA TERRANE BLOCK HISTORY
语种	英语
WOS研究方向	Geochemistry & Geophysics
WOS类目	Geochemistry & Geophysics
WOS记录号	WOS:000530895200063
来源期刊	JOURNAL OF GEOPHYSICAL RESEARCH-SOLID EARTH
来源机构	中国科学院青藏高原研究所
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/259740
推荐引用方式 GB/T 7714	Song, Peiping,Ding, Lin,Lippert, Peter C.,et al. Paleomagnetism of Middle Triassic Lavas From Northern Qiangtang (Tibet): Constraints on the Closure of the Paleo-Tethys Ocean[J]. 中国科学院青藏高原研究所,2020,125(2).
APA	Song, Peiping,Ding, Lin,Lippert, Peter C.,Li, Zhenyu,Zhang, Liyun,&Xie, Jing.(2020).Paleomagnetism of Middle Triassic Lavas From Northern Qiangtang (Tibet): Constraints on the Closure of the Paleo-Tethys Ocean.JOURNAL OF GEOPHYSICAL RESEARCH-SOLID EARTH,125(2).
MLA	Song, Peiping,et al."Paleomagnetism of Middle Triassic Lavas From Northern Qiangtang (Tibet): Constraints on the Closure of the Paleo-Tethys Ocean".JOURNAL OF GEOPHYSICAL RESEARCH-SOLID EARTH 125.2(2020).