DOI: 10.1007/s00531-017-1468-7
Scopus记录号: 2-s2.0-85015704601
论文题名: Early Cretaceous wedge extrusion in the Indo-Burma Range accretionary complex: implications for the Mesozoic subduction of Neotethys in SE Asia
作者: Zhang J. ; Xiao W. ; Windley B.F. ; Cai F. ; Sein K. ; Naing S.
刊名: International Journal of Earth Sciences
ISSN: 14373254
出版年: 2017
卷: 106, 期: 4 起始页码: 1391
结束页码: 1408
语种: 英语
英文关键词: Accretionary complex
; Early Cretaceous
; Indo-Burma Range
; Myanmar
; Neotethys
; Wedge extrusion
Scopus关键词: accretionary prism
; amphibolite
; blueschist
; Cretaceous
; deformation
; extensional tectonics
; geological mapping
; Mesozoic
; Tethys
; China
; Indo-Burma
; Myanmar
; Naga Hills
; Xizang
英文摘要: The Indo-Burma Range (IBR) of Myanmar, the eastern extension of the Yarlung-Tsangpo Neotethyan belt of Tibet in China, contains mélanges with serpentinite, greenschist facies basalt, chert, sericite schist, silty slate and unmetamorphosed Triassic sandstone, mudstone and siltstone interbedded with chert in the east, and farther north high-pressure blueschist and eclogite blocks in the Naga Hills mélange. Our detailed mapping of the Mindat and Magwe sections in the middle IBR revealed a major ~18 km antiformal isocline in a mélange in which greenschist facies rocks in the core decrease in grade eastwards and westwards symmetrically ‘outwards’ to lower grade sericite schist and silty slate, and at the margins to unmetamorphosed sediments, and these metamorphic rocks are structurally repeated in small-scale imbricated thrust stacks. In the Mindat section the lower western boundary of the isoclinal mélange is a thrust on which the metamorphic rocks have been transported over unmetamorphosed sediments of the Triassic Pane Chaung Group, and the upper eastern boundary is a normal fault. These relations demonstrate that the IBR metamorphic rocks were exhumed by wedge extrusion in a subduction-generated accretionary complex. Along strike to the north in the Naga Hills is a comparable isoclinal mélange in which central eclogite lenses are succeeded ‘outwards’ by layers of glaucophane schist and glaucophanite, and to lower grade greenschist facies sericite schist and slate towards the margins. In the Natchaung area (from west to east) unmetamorphosed Triassic sediments overlie quartzites, sericite schists, actinolite schists and meta-volcanic amphibolites derived from MORB-type basalt, which are in fault contact with peridotite. Olivine in the peridotite has undulatory extinction suggesting deformation at 600–700 °C, similar to the peak temperature of the amphibolite; these relations suggest generation in a metamorphic sole. The amphibolites have U/Pb zircon ages of 119 ± 3 Ma and 115 Ma, which are close to the zircon ages of nearby calc-alkaline granite and diorite, which belong to an active continental margin arc that extends along the western side of the Shan-Thai block. The IBR accretionary complex and the active continental margin arc were generated during Early Cretaceous (115–128 Ma) subduction of the Neotethys Ocean. © 2017, Springer-Verlag Berlin Heidelberg. URL: https://www.scopus.com/inward/record.uri?eid=2-s2.0-85015704601&doi=10.1007%2fs00531-017-1468-7&partnerID=40&md5=8c0c69a7c189a00f4de1d0b95cb7f0a5
Citation statistics:
资源类型: 期刊论文
标识符: http://119.78.100.158/handle/2HF3EXSE/70035
Appears in Collections: 影响、适应和脆弱性 气候减缓与适应
File Name/ File Size
Content Type
Version
Access
License
10.1007%2Fs00531-017-1468-7.pdf （11578KB） 期刊论文 作者接受稿 开放获取 View Download
作者单位: Tethys Research Center, Institute of Geology and Geophysics, Chinese Academy of Sciences, Beijing, China; Center for Excellence in Tibetan Plateau Earth Sciences, Beijing, China; Xinjiang Research Center for Mineral Resources, Xinjiang Institute of Ecology and Geography, Chinese Academy of Sciences, Urumqi, China; Department of Geology, University of Leicester, Leicester, United Kingdom; Key Laboratory of Continental Collision and Plateau Uplift, Institute of Tibetan Plateau Research, Beijing, China; Myanmar Geosciences Society, Yangon, Myanmar
Recommended Citation:
Zhang J.,Xiao W.,Windley B.F.,et al. Early Cretaceous wedge extrusion in the Indo-Burma Range accretionary complex: implications for the Mesozoic subduction of Neotethys in SE Asia[J]. International Journal of Earth Sciences,2017-01-01,106(4)