Moho-mapping in the Dabie ultrahigh-pressure collisional orogen, central China

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	Moho-mapping in the Dabie ultrahigh-pressure collisional orogen, central China
	Dong, SW (Dong, Shu-Wen)7; Li, QS (Li, Qiu-Sheng); Gao, R (Gao, Rui); Liu, FT (Liu, Fu-Tian); Xu, PF (Xu, Pei-Fen); Liu, XC (Liu, Xiao-Chun); Xue, HM (Xue, Huai-Min); Guan, Y (Guan, Ye)
刊名	AMERICAN JOURNAL OF SCIENCE
	2008
卷号	308 期号:4 页码:517-528
ISSN号	0002-9599
英文摘要	Eight wide angle reflection/refraction seismic profiles (with a total length of similar to 1700 km) and near-vertical reflection seismic profiles (with a total length of similar to 340 km) across the Dabie Orogen, eastern China have been completed in recent years, and allow the Moho depth and uppermost-mantle velocity to be mapped across similar to 40,000 km(2). These data reveal the detailed structure of the crust and upper mantle of this orogen that resulted from collision of the North China craton (NCC) with the Yangtze Craton (YC). The Dabie Orogen is an asymmetric orogen, with a thin crustal root (similar to 6 km) preserved in its northern part, highlighted by a north-dipping Moho. Compared to the nearly seismically-transparent lower crust, the Moho crust-mantle transition zone under the Dabie Orogen is a prominent north-dipping, strongly layered reflection, which is inferred to reflect the remnants of subduction of YC under the edge of the NCC or post-collisional exhumation of ultrahigh-pressure (UHP) rocks, and indicates the northward polarity of subduction of the YC. The Moho of the YC and NCC meet beneath the northern part of the Dabie Mountains, and the NCC Moho (north) is uplifted by similar to 4 to 5 km (Offset 1) over the YC Moho (south), marking the NCC-YC collision zone. Along the southern margin of the Dabie Mountains, the Moho below the Yangtze foreland is underthrust beneath the Moho of the Dabie Mountains, forming another Moho overlap (Offset 2) with a depth difference of 5 to 6 km. The two Moho overlaps (offsets) at both flanks of the Dabie Mountains formed two crustal-scale boundaries at depth between the NCC and the Dabie Orogen, and the Dabie Orogen and the YC respectively. Offset 1 is considered to be the Triassic suture between the YC and NCC as supported by the metamorphic ages of UHP rocks. This displays a wedge-shaped offset zone opening towards the east that acted as a channel for exhumation of UHP rocks. Offset 2 under the southern margin of the Dabie Orogen is connected to the Xiangfan-Guangji fault that gave rise to a large-scale thrust detachment that propagated towards the foreland of the Dabie Orogen during the Jurassic. Thus our Moho mapping confirms that there are structural remnants of the Triassic deep continental subduction preserved, despite the superimposed Jurassic deformation.
学科主题	构造地质学
WOS关键词	CRUSTAL STRUCTURE ; REFLECTION ; LITHOSPHERE ; EXHUMATION ; REFRACTION ; MOUNTAINS ; BELT
WOS研究方向	Geology
语种	英语
出版者	AMER JOURNAL SCIENCE
WOS记录号	WOS:000258131900005
内容类型	期刊论文
源URL	[http://119.78.100.197/handle/2HKVOGP0/38796]
专题	中国地质调查局
作者单位	1.[Dong, Shu-Wen 2.Chinese Acad Geol Sci, Inst Geomech, Beijing 100081, Peoples R China [Li, Qiu-Sheng 3.Gao, Rui 4.Xue, Huai-Min 5.Chinese Acad Geol Sci, Inst Geol, Beijing 100037, Peoples R China [Liu, Fu-Tian 6.Chinese Acad Sci, Inst Geol & Geophys, Beijing 100029, Peoples R China 7.中国地质科学院地质力学研究所
推荐引用方式 GB/T 7714	Dong, SW ,Li, QS ,Gao, R ,et al. Moho-mapping in the Dabie ultrahigh-pressure collisional orogen, central China[J]. AMERICAN JOURNAL OF SCIENCE,2008,308(4):517-528.
APA	Dong, SW .,Li, QS .,Gao, R .,Liu, FT .,Xu, PF .,...&Guan, Y .(2008).Moho-mapping in the Dabie ultrahigh-pressure collisional orogen, central China.AMERICAN JOURNAL OF SCIENCE,308(4),517-528.
MLA	Dong, SW ,et al."Moho-mapping in the Dabie ultrahigh-pressure collisional orogen, central China".AMERICAN JOURNAL OF SCIENCE 308.4(2008):517-528.