Subduction-related metasomatic mantle source in the eastern Central Asian Orogenic Belt: Evidence from amphibolites in the Xilingol Complex, Inner Mongolia, China
Subduction-related metasomatic mantle source in the eastern Central Asian Orogenic Belt: Evidence from amphibolites in the Xilingol Complex, Inner Mongolia, China
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中亚造山带东部俯冲相关交代地幔源区：来自内蒙古锡林郭勒杂岩角闪岩的证据
DOI：
10.1016/j.gr.2015.11.015
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发表时间：
2017-03
影响因子：
6.1
通讯作者：
Jianping Zheng
中科院分区：
文献类型：
--
作者：
Yilong Li;Fraukje Brouwer;Wenjiao Xiao;Kuolung Wang;Yuanhsi Lee;Biji Luo;Yuping Su;Jianping Zheng
中亚造山带(CAOB)主要形成于古生代，是由于古亚洲洋盆的闭合，伴随着远洋沉积物、洋壳、岩浆弧和前寒武纪地体的长期积累。古亚洲大洋俯冲-吸积作用和闭合的时间一直存在争议，并在镁铁质岩石的地球化学和同位素调查中得到解决，这可以对俯冲带环境的地球动力学产生重要的洞察。锡林郭勒杂岩位于CAOB北部俯冲-吸积带，主要由强烈变形的石英长石片麻岩组成，并夹层透镜状或准层片状角闪岩。通过对该杂岩中一套角闪岩的岩石学、地球化学和年代学的综合研究，约束了该带地幔来源和构造变质事件的性质。这些角闪岩的原岩为辉长岩和辉长闪长岩，侵入年龄约为340-321M a，εHf(T)为正值，范围为+22.89~+112.98。它们的TDM1模式年龄范围为455~855 Ma，峰值为617 Ma，表明这些镁铁质岩石来自亏损的大陆岩石圈地幔。原始岩浆是由含尖晶石的橄榄岩发生不同程度的部分熔融形成的。在岩浆分异过程中，橄榄石、单斜辉石和角闪石的分馏起主导作用，地壳混染很少或根本没有混染。镁铁质岩石来自新元古代晚期亏损的地幔来源，随后受到板岩衍生流体和沉积物影响的熔体或与沉积源岩熔体的富集性。CAOB北部增生带石炭纪镁铁质岩记录了早古生代古亚洲洋俯冲后的一次区域伸展事件。在晚石炭世(约340-309 Ma)，地幔岩浆的加入和洋壳的再循环对CAOB的地壳垂直生长起到了关键作用。角闪岩相变质作用影响锡林郭勒杂岩中的镁铁质岩石，年龄约为306~296 Ma(P=0.34~0.52 Gpa，T=675~708°C)，可能与南蒙古微大陆南缘下方弧前洋壳向北俯冲导致地壳增厚有关。索伦克带的最终形成可能一直持续到大约228年。
The Central Asian Orogenic Belt (CAOB) formed mainly in the Paleozoic due to the closure of the Paleo-Asian oceanic basins and accompanying prolonged accretion of pelagic sediments, oceanic crust, magmatic arcs, and Precambrian terranes. The timing of subduction–accretion processes and closure of the Paleo-Asian Ocean has long been controversial and is addressed in a geochemical and isotopic investigation of mafic rocks, which can yield important insight into the geodynamics of subduction zone environments. The Xilingol Complex, located on the northern subduction–accretion zone of the CAOB, mainly comprises strongly deformed quartzo-feldspathic gneisses with intercalated lenticular or quasi-lamellar amphibolite bodies. An integrated study of the petrology, geochemistry, and geochronology of a suite of amphibolites from the complex constrains the nature of the mantle source and the tectono-metamorphic events in the belt. The protoliths of these amphibolites are gabbros and gabbroic diorites that intruded at ca. 340–321 Ma with positive εHf(t)values ranging from + 2.89 to + 12.98. TheirTDM1model ages range from 455 to 855 Ma and peak at 617 Ma, suggesting that these mafic rocks are derived from a depleted continental lithospheric mantle. The primitive magma was generated by variable degrees of partial melting of spinel-bearing peridotites. Fractionation of olivine, clinopyroxene and hornblende has played a dominant role during magma differentiation with little or no crustal contamination. The mafic rocks are derived from a Late Neoproterozoic depleted mantle source that was subsequently enriched by melts affected by slab-derived fluids and sediments, or melts with a sedimentary source rock. The Carboniferous mafic rocks in the northern accretionary zone of the CAOB record a regional extensional event after the Early Paleozoic subduction of the Paleo-Asian Ocean. Both addition of mantle-derived magmas and recycling of oceanic crust played key roles in significant Late Carboniferous (ca. 340–309 Ma) vertical crustal growth in the CAOB. Amphibolite–facies metamorphism (P = 0.34–0.52 GPa, T = 675–708 °C) affected these mafic rocks in the Xilingol Complex at ca. 306–296 Ma, which may be related to the crustal thickening by northward subduction of a forearc oceanic crust beneath the southern margin of the South Mongolian microcontinent. The final formation of the Solonker zone may have lasted until ca. 228 Ma.
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影响因子：
2.7
作者：
O. Tomurtogoo;B. Windley;A. Kröner;G. Badarch;Dunyi Liu
通讯作者：
O. Tomurtogoo;B. Windley;A. Kröner;G. Badarch;Dunyi Liu
DOI：
10.1146/annurev-earth-060614-105254
发表时间：
2015-06
影响因子：
14.9
作者：
W. Xiao;B. Windley;S. Sun;Jiliang Li;Baochun Huang;Chunming Han;C. Yuan;Minjia Sun;Hanlin Chen-Hanli
通讯作者：
W. Xiao;B. Windley;S. Sun;Jiliang Li;Baochun Huang;Chunming Han;C. Yuan;Minjia Sun;Hanlin Chen-Hanli
影响因子：
3.9
作者：
Jin-Hui Yang;Sun‐Lin Chung;S. Wilde;Fu-Yuan Wu;M. Chu;C. Lo;H. Fan
通讯作者：
Jin-Hui Yang;Sun‐Lin Chung;S. Wilde;Fu-Yuan Wu;M. Chu;C. Lo;H. Fan
中亚造山带西部：增生造山作用和大陆生长的窗口
影响因子：
6.1
作者：
Wenjiao Xiao;M. Santosh
通讯作者：
M. Santosh
DOI：
10.1144/gsl.mem.1985.010.01.26
发表时间：
1985
期刊：
Geological Society, London, Memoirs
影响因子：
--
作者：
M. H. Dodson;E. McClelland-Brown
通讯作者：
M. H. Dodson;E. McClelland-Brown