Geochemistry and petrogenesis of Early Carboniferous volcanic rocks in East Junggar, North Xinjiang: Implications for post-collisional magmatism and geodynamic process
Geochemistry and petrogenesis of Early Carboniferous volcanic rocks in East Junggar, North Xinjiang: Implications for post-collisional magmatism and geodynamic process
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北疆东准噶尔早石炭世火山岩地球化学和岩石成因：对碰撞后岩浆作用和地球动力学过程的启示
DOI：
10.1016/j.gr.2014.08.018
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发表时间：
2015-12
影响因子：
6.1
通讯作者：
Piper, David J. W.
中科院分区：
文献类型：
--
作者：
Zhang, Yuanyuan;Guo, Zhaojie;Pe-Piper, Georgia;Piper, David J. W.
早石炭世巴塔玛依山组火山岩不整合地覆于北疆卡拉麦里造山带两侧、中亚造山带南部的糖蜜岩和蛇绿岩上。这些岩石显示了东准噶尔地区从图尔纳世开始的后碰撞环境，也标志着东准噶尔地区从最终合并到晚古生代体积幼花岗岩的重要过渡时期。火山岩由玄武岩、玄武岩安山岩、安山岩、粗面岩和流纹岩组成。基性岩和长英质岩均具有大离子亲石元素富集、轻稀土元素富集、Nb和Ta亏缺、低初始87sr /86Sr和高正Nd(t)的特征。确定了3组基性岩：第1组MgO、CaO、Ni、Cr含量最高，Na2O、Al2O3、La、Ba、La/Yb、Ba/Th含量最低，具有原生岩浆特征；第2组钙碱性和高钾钙碱性基性岩的K2O、P2O5、Th和Th/Nb最低，TiO2最高；第3组（钾碱性）的K2O、P2O5、La、Ba、La/Yb和Th/Nb含量最高，TiO2含量最低。a型长英质岩是基性岩浆分异形成的。地质和地球化学证据表明，巴塔玛依山组形成于板块断裂（滑脱）过程。第1组样品是由上升流软流圈减压熔融产生的，软流圈主要由尖晶石和石榴石（50:50）组成，在上升过程中被上覆的交代岩石圈富集。第2组是由热上升软流圈引起的含尖晶石岩石圈地幔5-10%的部分熔融引起的，其中板源流体的贡献占主导地位。低部分熔融（3 - 5%）的地幔楔和/或增厚的岩石圈地幔富集了板块衍生成分，形成了第3组。板块断裂作为一个重要的地球动力学过程，解释了343.5 Ma - 330 Ma碰撞后的岩浆活动，提供了碰撞后CAOB壳幔相互作用的模型。
Early Carboniferous volcanic rocks in the Batamayineishan Formation overlie unconformably the molasse deposits and the ophiolitic mélanges and are restricted in narrow zones along both sides of the Kalamaili orogenic belt in North Xinjiang, southern Central Asian Orogenic Belt. These rocks demonstrate the post-collisional setting in East Junggar commenced in Tournaisian and also mark an important transitional period from the final amalgamation to late Paleozoic voluminous juvenile granitoids in East Junggar. The volcanic rocks are composed of basalt, basaltic andesite, andesite, trachyte and rhyolite. Both mafic and felsic rocks are characterized by enrichments in large ion lithophile elements, light rare earth elements and depletion in Nb and Ta, low initial87Sr/86Sr and high, positive ɛNd(t). Three groups of mafic rocks have been identified: Shoshonitic group 1 has the highest MgO, CaO, Ni and Cr and the lowest Na2O, Al2O3, La, Ba, La/Yb and Ba/Th with primary magma features; group 2 calc-alkaline and high-K calc-alkaline mafic rocks have the lowest K2O, P2O5, Th and Th/Nb, and the highest TiO2; and group 3 (shoshonitic to potassic alkaline) has the highest K2O, P2O5, La, Ba, La/Yb and Th/Nb, and the lowest TiO2. The A-type-like felsic rocks were derived from the differentiation of the mafic magma. Geological and geochemical evidences indicate that the Batamayineishan Formation was generated from the process of slab breakoff (detachment). Group 1 samples are produced by decompressional melting of the upwelling asthenosphere mainly composed of spinel and garnet (50:50) lherzolite which has been enriched by overlying metasomatized lithosphere during ascent. Group 2 is derived from 5–10% partial melting of shallower spinel-bearing lithospheric mantle induced by the hot rising asthenosphere, where the contribution of slab-derived fluid is predominant. Low partial melting (3–5%) of the mantle wedge and/or thickened lithospheric mantle enriched by slab-derived components generates group 3. Slab breakoff as an important geodynamic process accounts for the post-collisional magmatism between 343.5 Ma–330 Ma, providing a model for post-collisional crust–mantle interaction in the CAOB.
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影响因子：
6.1
作者：
M. M. Buslov-M.;Tsuyoshi Watanabe;I. Y. Saphonova;K. Iwata;A. V. Travin;M. Akiyama
通讯作者：
M. M. Buslov-M.;Tsuyoshi Watanabe;I. Y. Saphonova;K. Iwata;A. V. Travin;M. Akiyama
影响因子：
3.5
作者：
J. Liégeois;J. Navez;J. Hertogen;R. Black
通讯作者：
J. Liégeois;J. Navez;J. Hertogen;R. Black
影响因子：
3.9
作者：
J. Pearce;P. E. Baker;P. Harvey;I. W. Luff
通讯作者：
J. Pearce;P. E. Baker;P. Harvey;I. W. Luff
新疆准噶尔地体北部泥盆纪岛弧的苦味岩和相关熔岩的地球化学：对岩石成因、弧地幔来源和构造环境的影响
影响因子：
3.5
作者：
张招崇
通讯作者：
张招崇
影响因子：
3
作者：
Gaoxue Yang;Yongjun Li;Hongen Wu;X. Zhong;Baokai Yang;Cunxing Yan;Jing Yan;Guohui Si
通讯作者：
Gaoxue Yang;Yongjun Li;Hongen Wu;X. Zhong;Baokai Yang;Cunxing Yan;Jing Yan;Guohui Si