中国科学院机构知识库网格
Chinese Academy of Sciences Institutional Repositories Grid
Tracing a subducted ridge-transform system in a late Carboniferous accretionary prism of the southern Altaids: Orthogonal sanukitoid dyke swarms in Western Junggar, NW China

文献类型:期刊论文

作者Ma, Chong1,2,3; Xiao, Wenjiao1,3; Windley, Brian F.4; Zhao, Guiping2; Han, Chunming1,3; Zhang, Ji'en1,3; Luo, Jun1,3; Li, Chao1,3
刊名LITHOS
出版日期2012-05-01
卷号140页码:152-165
关键词Dyke swarms Sanukitoids Paleostress inversion Ridge subduction Western Junggar Altaids
ISSN号0024-4937
DOI10.1016/j.lithos.2012.02.005
文献子类Article
英文摘要Two sets of Late Paleozoic, orthogonal, dioritic dyke swarms are defined in the eastern part of the Western Junggar accretionary collage in the southern Altaids. Dioritic dykes (hornblende + plagioclase) are characterized by relatively high SiO2, elevated MgO, Na2O, K2O, Mg-#, Ni, Si and Cr contents, La/Yb ratios, very low Y contents, and enrichments in large ion lithophile elements (LILE) and light rare earth elements (LREE), which are all comparable with those of sanukitoids. These dioritic dykes have low (Sr-87/Sr-86) ratios (mostly between 0.70366 and 0.70381) and high positive epsilon(Nd) (t) (+6.6 to +8.4) values, suggesting they were sourced from a depleted mantle. Accordingly, these dioritic dykes were probably derived by mixing of depleted mantle components that originated from upwelling of asthenosphere through a slab window with melts that were derived by dehydration of a subducted slab. Detailed mapping and structural data of the dyke swarms indicate that the NW/SE-trending set was earlier than the NE/SW-trending dykes. Paleostress analysis and inversion of the dyke swarms indicate that an early NE/SW-extension was associated with a NW/SE-trending slab window, and was followed by a slightly later NW/SE-extension that was associated with a NE/SW-trending slab window. Field relationships, together with published age constraints, suggest that these two dyke swarms were intruded in the Late Carboniferous. Therefore two orthogonal slab windows were opened, one (NE-SW) after the other (NW-SE) during this time period. A subducted ridge transform system could well account for, and is consistent with, these relationships. We propose that in the Late Carboniferous a NW/SE-trending mid-oceanic ridge was subducted beneath the Darbut trench generating large-scale, closely spaced NW/SE-trending dykes that were intruded through a slab window. That event was followed by subduction of a NE/SW-trending transform fault (fracture zone) that connected with the earlier NW/SE-trending ridge, producing widely spaced NE/SW-trending dykes that were intruded through a NE/SW-trending vertical slab window. This new approach to the relationships between dyke swarms, adakitic/sanukitoid magmatism, ridge subduction and slab windows has broad implications for tectonic reconstruction of ancient accretionary orogens. (C) 2012 Elsevier B.V. All rights reserved.
WOS关键词SETOUCHI VOLCANIC BELT ; HIGH-MAGNESIAN ANDESITES ; LOWER CONTINENTAL-CRUST ; HIGH-MG DIORITES ; CENTRAL-ASIA ; SLAB WINDOW ; TECTONIC EVOLUTION ; SOUTHWEST JAPAN ; NORTH-AMERICA ; PALEOSTRESS RECONSTRUCTIONS
WOS研究方向Geochemistry & Geophysics ; Mineralogy
语种英语
WOS记录号WOS:000303095400011
出版者ELSEVIER SCIENCE BV
资助机构Major State Basic Research Development Program of China(2007CB411307) ; Major State Basic Research Development Program of China(2007CB411307) ; Chinese Academy of Sciences(KZCX2-YW-Q04-08) ; Chinese Academy of Sciences(KZCX2-YW-Q04-08) ; National Natural Science Foundation of China(40725009 ; National Natural Science Foundation of China(40725009 ; 40772136) ; 40772136) ; Major State Basic Research Development Program of China(2007CB411307) ; Major State Basic Research Development Program of China(2007CB411307) ; Chinese Academy of Sciences(KZCX2-YW-Q04-08) ; Chinese Academy of Sciences(KZCX2-YW-Q04-08) ; National Natural Science Foundation of China(40725009 ; National Natural Science Foundation of China(40725009 ; 40772136) ; 40772136) ; Major State Basic Research Development Program of China(2007CB411307) ; Major State Basic Research Development Program of China(2007CB411307) ; Chinese Academy of Sciences(KZCX2-YW-Q04-08) ; Chinese Academy of Sciences(KZCX2-YW-Q04-08) ; National Natural Science Foundation of China(40725009 ; National Natural Science Foundation of China(40725009 ; 40772136) ; 40772136) ; Major State Basic Research Development Program of China(2007CB411307) ; Major State Basic Research Development Program of China(2007CB411307) ; Chinese Academy of Sciences(KZCX2-YW-Q04-08) ; Chinese Academy of Sciences(KZCX2-YW-Q04-08) ; National Natural Science Foundation of China(40725009 ; National Natural Science Foundation of China(40725009 ; 40772136) ; 40772136)
源URL[http://ir.iggcas.ac.cn/handle/132A11/84554]  
专题中国科学院地质与地球物理研究所
通讯作者Xiao, Wenjiao
作者单位1.Chinese Acad Sci, State Key Lab Lithospher Evolut, Inst Geol & Geophys, Beijing 100029, Peoples R China
2.Chinese Acad Sci, Grad Univ, Coll Earth Sci, Lab Computat Geodynam, Beijing 100049, Peoples R China
3.Chinese Acad Sci, Xinjiang Res Ctr Mineral Resources, Xinjiang Inst Ecol & Geog, Urumqi 830011, Peoples R China
4.Univ Leicester, Dept Geol, Leicester LE1 7RH, Leics, England
推荐引用方式
GB/T 7714
Ma, Chong,Xiao, Wenjiao,Windley, Brian F.,et al. Tracing a subducted ridge-transform system in a late Carboniferous accretionary prism of the southern Altaids: Orthogonal sanukitoid dyke swarms in Western Junggar, NW China[J]. LITHOS,2012,140:152-165.
APA Ma, Chong.,Xiao, Wenjiao.,Windley, Brian F..,Zhao, Guiping.,Han, Chunming.,...&Li, Chao.(2012).Tracing a subducted ridge-transform system in a late Carboniferous accretionary prism of the southern Altaids: Orthogonal sanukitoid dyke swarms in Western Junggar, NW China.LITHOS,140,152-165.
MLA Ma, Chong,et al."Tracing a subducted ridge-transform system in a late Carboniferous accretionary prism of the southern Altaids: Orthogonal sanukitoid dyke swarms in Western Junggar, NW China".LITHOS 140(2012):152-165.

入库方式: OAI收割

来源:地质与地球物理研究所

浏览0
下载0
收藏0
其他版本

除非特别说明,本系统中所有内容都受版权保护,并保留所有权利。