First Triassic palaeomagnetic constraints from Junggar (NW China) and their implications for the Mesozoic tectonics in Central Asia

doi:10.1016/j.jseaes.2013.01.023

	First Triassic palaeomagnetic constraints from Junggar (NW China) and their implications for the Mesozoic tectonics in Central Asia
	Choulet, Flavien 1; Chen, Yan 1; Cogne, Jean-Pascal 2; Rabillard, Aurelien 1; Wang, Bo 3; Lin, Wei 4; Faure, Michel 1; Cluzel, Dominique 5
刊名	JOURNAL OF ASIAN EARTH SCIENCES
	2013-12-15
卷号	78 页码:371-394
关键词	Palaeomagnetism Junggar Transcurrent tectonics Triassic Reactivation
ISSN号	1367-9120
DOI	10.1016/j.jseaes.2013.01.023
文献子类	Article
英文摘要	Northwestern China belts result from the Palaeozoic collage of Central Asia and the subsequent reactivations due to far-field effects of the Mesozoic Tibetan and the Cenozoic Himalayan collisions. Triassic is a crucial period to understand and decipher the tectonics related to these two episodes. About 250 oriented palaeomagnetic cores from 43 sites were collected from six sections of Upper Permian to Late Triassic sandstone, in South and West Junggar, Northwestern China. Thermomagnetic, IRM and hysteresis measurements reveal magnetite as the main carrier of the magnetic remanence with minor hematite and maghemite. Stepwise thermal demagnetisation has generally isolated two components. The low temperature component, up to 300-350 degrees C, displays a direction consistent with the present-day geomagnetic field. The locality-mean directions related to the high temperature component (above 350 degrees C) were also calculated. Two out of six sections display intense viscous magnetisation and the occurrence of maghemite reveals a possible Cenozoic chemical remagnetisation for these two localities. For the other four localities, we assume that the magnetisation is primary because: (1) AMS measurements reveal a primary fabric, (2) there are local occurrences of antipodal polarities, and (3) palaeolatitudes of tilt-corrected poles are compatible with previous studies. The consistency between the Early Triassic poles of West and South Junggar indicates that Junggar evolved as a rigid block only since Early Mesozoic. The comparison of the Late Palaeozoic and the Early Mesozoic poles of Junggar and those of Siberia and Tarim shows major rotations between the Late Permian and the Late Jurassic-Early Cretaceous. These periods of discrete rotations are characterized by strike-slip faulting in Tianshan and Altai and they may correlate with the major episodes of coarse-grained detrital sedimentation and uplift of the range. Especially, the counter-clockwise rotations of Junggar relative to Tarim and Siberia, which occurred between the Early and the Late Triassic and between the Late Triassic and the Late Jurassic, are accommodated by transpressive tectonics in the Tianshan and the Altai belts. This reactivation is a far-field effect of Tibetan blocks diachronous collisions. Therefore, these first Triassic palaeomagnetic results from Junggar infer that post-Carboniferous rotations were due to the combined effect of the post-orogenic transcurrent movement and the Mesozoic oblique reactivation. (C) 2013 Elsevier Ltd. All rights reserved.
WOS关键词	NORTHERN TIEN-SHAN ; TRUE POLAR WANDER ; TURPAN-HAMI BASIN ; NORTHWEST CHINA ; TIAN-SHAN ; WEST JUNGGAR ; SEDIMENTARY RECORD ; SOUTHERN JUNGGAR ; TARIM BASIN ; GEODYNAMIC EVOLUTION
WOS研究方向	Geology
语种	英语
出版者	PERGAMON-ELSEVIER SCIENCE LTD
WOS记录号	WOS:000327804600025
资助机构	National Basic Research Program of China(2009CB825008 ; National Basic Research Program of China(2009CB825008 ; Chinese National ST Major Project(2008ZX05008) ; Chinese National ST Major Project(2008ZX05008) ; project "Paleomagnitic study on the tectonic and paleogeographic evolution of northwest of China" ; project "Paleomagnitic study on the tectonic and paleogeographic evolution of northwest of China" ; SINOPEC ; SINOPEC ; National Nature Science Foundation of China(40821002 ; National Nature Science Foundation of China(40821002 ; 2007CB411301) ; 2007CB411301) ; 40802043) ; 40802043) ; National Basic Research Program of China(2009CB825008 ; National Basic Research Program of China(2009CB825008 ; Chinese National ST Major Project(2008ZX05008) ; Chinese National ST Major Project(2008ZX05008) ; project "Paleomagnitic study on the tectonic and paleogeographic evolution of northwest of China" ; project "Paleomagnitic study on the tectonic and paleogeographic evolution of northwest of China" ; SINOPEC ; SINOPEC ; National Nature Science Foundation of China(40821002 ; National Nature Science Foundation of China(40821002 ; 2007CB411301) ; 2007CB411301) ; 40802043) ; 40802043) ; National Basic Research Program of China(2009CB825008 ; National Basic Research Program of China(2009CB825008 ; Chinese National ST Major Project(2008ZX05008) ; Chinese National ST Major Project(2008ZX05008) ; project "Paleomagnitic study on the tectonic and paleogeographic evolution of northwest of China" ; project "Paleomagnitic study on the tectonic and paleogeographic evolution of northwest of China" ; SINOPEC ; SINOPEC ; National Nature Science Foundation of China(40821002 ; National Nature Science Foundation of China(40821002 ; 2007CB411301) ; 2007CB411301) ; 40802043) ; 40802043) ; National Basic Research Program of China(2009CB825008 ; National Basic Research Program of China(2009CB825008 ; Chinese National ST Major Project(2008ZX05008) ; Chinese National ST Major Project(2008ZX05008) ; project "Paleomagnitic study on the tectonic and paleogeographic evolution of northwest of China" ; project "Paleomagnitic study on the tectonic and paleogeographic evolution of northwest of China" ; SINOPEC ; SINOPEC ; National Nature Science Foundation of China(40821002 ; National Nature Science Foundation of China(40821002 ; 2007CB411301) ; 2007CB411301) ; 40802043) ; 40802043)
内容类型	期刊论文
源URL	[http://ir.iggcas.ac.cn/handle/132A11/87236]
专题	中国科学院地质与地球物理研究所
通讯作者	Choulet, Flavien
作者单位	1.Univ Orleans, CNRS, BRGM, Inst Sci Terre Orleans,UMR 7327, F-45071 Orleans 2, France 2.Univ Paris Diderot, CNRS, Inst Phys Globe Paris, Sorbonne Paris Cite,UMR 7154, F-75005 Paris, France 3.Nanjing Univ, Dept Earth Sci, Nanjing 210008, Jiangsu, Peoples R China 4.Chinese Acad Sci, Inst Geol & Geophys, State Key Lab Lithospher Evolut, Beijing 100029, Peoples R China 5.Univ Nouvelle Caledonie, EA 3325, Noumea 98851, New Caledonia
推荐引用方式 GB/T 7714	Choulet, Flavien,Chen, Yan,Cogne, Jean-Pascal,et al. First Triassic palaeomagnetic constraints from Junggar (NW China) and their implications for the Mesozoic tectonics in Central Asia[J]. JOURNAL OF ASIAN EARTH SCIENCES,2013,78:371-394.
APA	Choulet, Flavien.,Chen, Yan.,Cogne, Jean-Pascal.,Rabillard, Aurelien.,Wang, Bo.,...&Cluzel, Dominique.(2013).First Triassic palaeomagnetic constraints from Junggar (NW China) and their implications for the Mesozoic tectonics in Central Asia.JOURNAL OF ASIAN EARTH SCIENCES,78,371-394.
MLA	Choulet, Flavien,et al."First Triassic palaeomagnetic constraints from Junggar (NW China) and their implications for the Mesozoic tectonics in Central Asia".JOURNAL OF ASIAN EARTH SCIENCES 78(2013):371-394.