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DOI	10.1016/j.tecto.2014.04.032
	Cenozoic clockwise rotation of the Tengchong block, southeastern Tibetan Plateau: A paleomagnetic and geochronologic study
	Kornfeld, Daniela; Eckert, Sabine; Appel, Erwin; Ratschbacher, Lothar; Sonntag, Benita-Lisette; Pfaender, Joerg A.; Ding, Lin; Liu, Deliang
通讯作者	Appel, E (通讯作者)
发表日期	2014
ISSN	0040-1951
EISSN	1879-3266
起始页码	105
结束页码	122
卷号	628
英文摘要	Paleomagnetic data from similar to 50-35 Ma (likely similar to 40 Ma) mafic dykes in Yunnan, southeastern Tibetan Plateau, cutting similar to 115 Ma granitoids record the rotation of the Tengchong (Lhasa) block around the East Himalayan Syntaxis (EHS). Ti-rich titanomagnetite and magnetite carry a primary magnetic component (Group1); a magnetic overprint resides in magnetite (Group2), likely induced by low-grade metamorphism between similar to 30 and 10 Ma. The tilt-corrected overall mean directions are D/I = 89.8 degrees/35.1 degrees for Group1 and D/I = 33.3 degrees/41.4 degrees for Group2. These data imply a clockwise rotation of similar to 87 degrees (87.3 +/- 12.5 degrees) of the Tengchong block since remanence acquisition at similar to 40 Ma with respect to stable Eurasia. The average rotation rate of 2.18 +/- 0.31 degrees/Myr is at the upper limit of the present-day rotation rates around the EHS obtained from GPS velocities and Quaternary strain rates. The remagnetized Group2 indicates a-poorly defined-rotation of similar to 31 degrees (31.2 +/- 32.9 degrees). Our key results- the detection of similar to 87 degrees clockwise rotation, with high rotation rates following the India-Asia collision, and a decrease in rotation rates during the Miocene - suggest that first the Tengchong block rotated rapidly around the EHS, synchronous with eastward tectonic escape of lithospheric blocks. The later, slower, clockwise rotation-similar to those recorded geodetically-may be related to viscous flow of Tibetan crust. (C) 2014 Elsevier B.V. All rights reserved.
关键词	THAI-MALAY BLOCK RIVER SHEAR ZONE WESTERN YUNNAN INDO-CHINA CRETACEOUS ROCKS TECTONIC EVOLUTION HIGH TOPOGRAPHY EASTERN TIBET POLAR WANDER LOWER CRUST
英文关键词	Paleomagnetism; Geochronology; Tibetan Plateau; Eastern Himalayan Syntaxis; Tengchong block; Crustal rotation
语种	英语
WOS研究方向	Geochemistry & Geophysics
WOS类目	Geochemistry & Geophysics
WOS记录号	WOS:000340333000007
来源期刊	TECTONOPHYSICS
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/258318
推荐引用方式 GB/T 7714	Kornfeld, Daniela,Eckert, Sabine,Appel, Erwin,et al. Cenozoic clockwise rotation of the Tengchong block, southeastern Tibetan Plateau: A paleomagnetic and geochronologic study[J]. 中国科学院青藏高原研究所,2014,628.
APA	Kornfeld, Daniela.,Eckert, Sabine.,Appel, Erwin.,Ratschbacher, Lothar.,Sonntag, Benita-Lisette.,...&Liu, Deliang.(2014).Cenozoic clockwise rotation of the Tengchong block, southeastern Tibetan Plateau: A paleomagnetic and geochronologic study.TECTONOPHYSICS,628.
MLA	Kornfeld, Daniela,et al."Cenozoic clockwise rotation of the Tengchong block, southeastern Tibetan Plateau: A paleomagnetic and geochronologic study".TECTONOPHYSICS 628(2014).