气候变化领域集成服务门户(CCPortal): Position of the Lhasa terrane prior to India-Asia collision derived from palaeomagnetic inclinations of 53 Ma old dykes of the Linzhou Basin: constraints on the age of collision and post-collisional shortening within the Tibetan Plateau

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DOI	10.1111/j.1365-246X.2010.04698.x
	Position of the Lhasa terrane prior to India-Asia collision derived from palaeomagnetic inclinations of 53 Ma old dykes of the Linzhou Basin: constraints on the age of collision and post-collisional shortening within the Tibetan Plateau
	Liebke, Ursina; Appel, Erwin; Ding, Lin; Neumann, Udo; Antolin, Borja; Xu, Qiang
通讯作者	Liebke, U (通讯作者)
发表日期	2010
ISSN	0956-540X
EISSN	1365-246X
起始页码	1199
结束页码	1215
卷号	182 期号:3
英文摘要	P>Seventeen sites were drilled from ca. 53 Ma old mafic dykes intruded in the Linzizong Formation of the Linzhou Basin for palaeomagnetic studies. From 10 sites a higher coercivity component demagnetized between 20 and 100 mT could be isolated. Detailed rockmagnetic analyses reveal Ti-rich titanomagnetite as the remanence carrier, which indicates that the rock is not much altered and the remanent magnetization is likely of primary origin. This is supported by a positive fold test. Tilt correction could be performed by the bedding of overlying fluvial lacustrine sediments and tilt angles of ignimbrite columns post-dating the dyke emplacement. Bedding corrected directions give an overall mean direction of D/I = 12.3 degrees/27.2 degrees (alpha(95) = 10.6 degrees, k = 21.7, N = 10) corresponding to a palaeolatitude of 14.4 degrees +/- 5.8 degrees N. Comparison with previous Cretaceous data mainly from the Takena Formation yields a stable position of the Lhasa terrane during Cretaceous and Early Eocene. The difference between expected palaeolatitudes determined from the APWP of Eurasia and observed ones reveals relative northward movement of the Lhasa terrane of ca. 1847 +/- 763 km since early Eocene. This is attributed to indentation of India into Asia and implies a considerable amount of north-south crustal shortening. Together with the extent of 'Greater India', we can derive an age for the India-Asia collision between ca. 53-49 Ma with a 95 per cent confidence limit of +/- 6 Ma.
关键词	AVERAGED GEOMAGNETIC-FIELD SOUTHERN TIBET MAGNETIC-PROPERTIES TECTONIC EVOLUTION DOMAIN-STRUCTURE VOLCANIC-ROCKS TI TITANOMAGNETITES DEFORMATION BLOCK
英文关键词	Palaeomagnetism applied to tectonics; Rock and mineral magnetism; Continental margins: convergent
语种	英语
WOS研究方向	Geochemistry & Geophysics
WOS类目	Geochemistry & Geophysics
WOS记录号	WOS:000280997700008
来源期刊	GEOPHYSICAL JOURNAL INTERNATIONAL
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/257752
推荐引用方式 GB/T 7714	Liebke, Ursina,Appel, Erwin,Ding, Lin,et al. Position of the Lhasa terrane prior to India-Asia collision derived from palaeomagnetic inclinations of 53 Ma old dykes of the Linzhou Basin: constraints on the age of collision and post-collisional shortening within the Tibetan Plateau[J]. 中国科学院青藏高原研究所,2010,182(3).
APA	Liebke, Ursina,Appel, Erwin,Ding, Lin,Neumann, Udo,Antolin, Borja,&Xu, Qiang.(2010).Position of the Lhasa terrane prior to India-Asia collision derived from palaeomagnetic inclinations of 53 Ma old dykes of the Linzhou Basin: constraints on the age of collision and post-collisional shortening within the Tibetan Plateau.GEOPHYSICAL JOURNAL INTERNATIONAL,182(3).
MLA	Liebke, Ursina,et al."Position of the Lhasa terrane prior to India-Asia collision derived from palaeomagnetic inclinations of 53 Ma old dykes of the Linzhou Basin: constraints on the age of collision and post-collisional shortening within the Tibetan Plateau".GEOPHYSICAL JOURNAL INTERNATIONAL 182.3(2010).