岩石学报  2013, Vol. 29 Issue (1): 303-316   PDF    
西准噶尔玛依勒蛇绿混杂岩锆石U-Pb年代学、地球化学及源区特征
杨高学1, 李永军1, 杨宝凯1,2, 刘振伟1, 佟丽莉1, 张洪伟3     
1. 长安大学地球科学与资源学院,西部矿产资源与地质工程教育部重点实验室,西安 710054;
2. 青岛地质工程勘察院,青岛 266071;
3. 新疆维吾尔族自治区地质矿产勘查开发局第七地质大队,乌苏 833000
摘要: 西准噶尔地区出露多条蛇绿混杂岩带,对其进行精确的锆石U-Pb年代学及岩石地球化学研究可以为揭示西准噶尔地区古大洋形成与演化过程、恢复古构造格局及追溯岩浆源区物质来源提供线索。本文对玛依勒蛇绿混杂岩中的辉长岩及玄武岩进行了LA-ICP-MS锆石U-Pb年代学及全岩地球化学研究,获得辉长岩中锆石的加权平均206Pb/238U年龄为572.2±9.2Ma,属于早震旦纪,该年龄是准噶尔乃至北疆地区报道的最古老的蛇绿混杂岩年龄。玛依勒蛇绿混杂岩中的枕状玄武岩为碱性玄武岩,岩石具有高Ti (TiO2=1.65%~3.13%)、高Fe (FeOT=8.93%~18.11%)、高Mg (MgO=3.95%~5.27%) 及高P (P2O5=0.17%~0.51%),Th/Ta比值相对较高(=1.1~1.9),LREE和HREE分异较为明显((La/Yb)N=2.5~7.4) 等特征,这些特征与洋岛玄武岩类似,可能形成于大洋板内的洋岛或海山环境。其中的辉长岩地球化学特征不同于玄武岩,可能形成与俯冲有关的环境。玛依勒蛇绿混杂岩中玄武岩与EMI型洋岛玄武岩具有相似的地球化学特征,表明其岩浆源区可能为EMI型富集地幔。岩石成因与软流圈地幔关系密切,软流圈的上涌导致尖晶石相二辉橄榄岩地幔源区大比例部分熔融,是岩石圈-软流圈地幔相互作用的产物。
关键词: 玛依勒蛇绿混杂岩     锆石U-Pb年代学     地球化学     洋岛玄武岩     西准噶尔    
Zircon U-Pb geochronology and geochemistry of the Mayile ophiolitic mélange in West Junggar and implications for source nature
YANG GaoXue1, LI YongJun1, YANG BaoKai1,2, LIU ZhenWei1, TONG LiLi1, ZHANG HongWei3     
1. Earth Science & Resources College of Chang'an University, Key Laboratory of Western China's Mineral Resources and Geological Engineering, Ministry of Education, Xi'an 710054, China;
2. The Qingdao Geological Engineering Investigation Institute, Qingdao 266071, China;
3. No. 7 Geological Survey Team, Xinjiang Bureau of Geology and Mineral Resource Exploration, Wusu 833000, China
Abstract: Precise zircon U-Pb dating and geochemical composition analysis on the ophiolitic mélange belts in West Junggar. It is a clue for forming and evolution of the pale-ocean, rebuilding palaeotectonics and tracing the source of magma source. LA-ICP-MS zircon U-Pb weighted mean 206Pb/238U age of the gabbros from the Mayile ophiolitic mélange in the West Junggar is 572.2±9.2Ma, belong to Early Sinian, this is oldest age from ophiolitic mélange in the Junggar as well as North Xinjiang. The alkalic pillow basalts from Mayile ophiolitic mélange are similar with the ocean island basalt (OIB), characteristics by high Ti (TiO2=1.65%~3.13%), Fe (FeOT=8.93%~18.11%), Mg (MgO=3.95%~5.27%) and P (P2O5=0.17%~0.51%), and high Th/Ta ratios (1.1~1.9), and clear differentiation between LREE and HREE ((La/Yb)N=2.5~7.4). It is assumed that the magma extruded into ocean island or seamount of the ocean floor. However, the geochemical characteristics of the gabbros different from basalts, may be form subduction-related setting. The geochemical features of the basalts show they have ocean island basalts, derived from EMI type enriched-mantle. Petrogenesis is closely related to asthenosphere mantle, asthenospheric mantle upwelling led to a large proportion of spinel lherzolite mantle partial melting to forming the basalt magam. It is a product of asthenosphere interacted with lithosphere.
Key words: Mayile ophiolitic mélange     Zircon U-Pb geochronology     Geochemistry     Ocean island basalt (OIB)     West Junggar    
1 引言

蛇绿岩是仰冲到大陆地壳之上的古大洋岩石圈残片,其形成时代和形成环境的确定对于恢复古大洋形成演化史和重建古板块构造格局等具有重要的大地构造意义。西准噶尔是巨型中亚造山带的一部分,也是中亚-兴蒙巨型构造成矿域的重要组成部分(肖序常等,1992李锦轶,2004Zhu et al., 2005Xiao et al., 2008)(图 1a)。该地区蛇绿岩分布广泛,保存比较完整,主要包括唐巴勒、玛依勒、达尔布特、白碱滩、巴尔雷克等多条蛇绿岩带(图 1b),中外学者都有过较多研究(Kwon et al., 1989;张弛和黄萱,1992;张立飞,1997徐新等,2006何国琦等,2007朱永峰和徐新,2007雷敏等,2008朱永峰等,2008辜平阳等,2009刘希军等,2009陈博和朱永峰,2010陈石和郭召杰,2010; Yang et al., 2011;Xu et al., 2012),其中玛依勒蛇绿岩带是西准噶尔地区比较重要的蛇绿岩带之一,由其代表的洋(盆) 的演化历史对恢复和重建西准噶尔古生代以来的地质演化过程具有重要意义。但是,对其形成时代仍然存在争议:新疆第一区调大队在玛依勒蛇绿混杂岩建造上部的细碎屑岩中获得中晚志留世的笔石、珊瑚等,其上依次发育大量的晚志留世化石和早泥盆世沉积,因此确定其形成时代为中志留世(新疆维吾尔自治区地质矿产局,1993);朱宝清等(1987a)对玛依勒蛇绿混杂岩中火山岩进行全岩Rb-Sr等时线测年获得年龄421Ma;最近,魏荣珠等(2010)用同样的方法在玄武岩中获得年龄435.3±6.5Ma和432.5±7.4Ma。

图 1 西准噶尔地质简图及玛依勒蛇绿混杂岩分布图 (a)-中亚造山带构造格架图(据Jahn et al., 2000);(b)-西准噶尔区域地质简图(据新疆维吾尔自治区地质矿产局,1993Geng et al., 2009Tang et al., 2010);(c)-玛依勒蛇绿混杂岩分布图 Fig. 1 Simplified geological sketch for study region and distribution map of the Mayile ophiolitic mélange (a)-simplified tectonic sketch of the Central Asian Orogenic Belt (after Jahn et al., 2000); (b)-regional geological map of the West Junggar, Xinjiang (modified after BGMRX, 1993; Geng et al., 2009; Tang et al., 2010); (c)-distribution map of the Mayile ophiolitic mélange in the West Junggar

目前,不仅对玛依勒蛇绿混杂岩的侵位时限存在不同的认识,而且对其构造背景的认识也存在争议,主要包括:岛弧环境(何国琦和李茂松,2001Wang et al., 2003),弧后盆地环境(肖序常等,1991),弧前盆地环境(Peng,1996),大洋中脊(MOR,张弛和黄萱,1992;韩松等,2004),大陆-大洋的过渡区(朱宝清等,1987b)。这对约束西准噶尔古生代板块构造演化造成很大困难。本文在对玛依勒蛇绿混杂岩中辉长岩进行精确的LA-ICP-MS锆石U-Pb定年,限定其准确的侵位时限的同时,对辉长岩和玄武岩进行了详细的岩石地球化学研究,依据区域地质资料和前人研究成果,对其构造背景及源区特征进行深入探讨。

2 区域地质

西准噶尔主要由一系列的增生杂岩带、古生代岩浆弧构成(Windley et al., 2007Xiao et al., 2009Han et al., 2010),其主要构造特征为NE-SW向断裂非常发育,由北向南依次为巴尔雷克和达尔布特断裂,它们控制着花岗岩和蛇绿岩的分布(图 1b)。该地区出露大量晚古生代中酸性侵入体,根据产状可以分为两类:一类呈大岩基状产出(如:庙尔沟、阿克巴斯套、克拉玛依、红山及哈图岩体等) 的晚石炭世-中二叠世后碰撞花岗岩类(Chen and Jahn, 2004韩宝福等, 2006, 2010苏玉平等,2006范裕等, 2007Zhou et al., 2008Chen et al., 2010陈家富等,2010),但也有学者认为其就位于洋脊俯冲有关的构造背景(高山林等,2006张连昌等,2006Xiao et al., 2008Geng et al., 2009Tang et al., 2010Yin et al., 2010);另一类是以小岩株或岩脉形式出露(如:包古图Ⅴ岩体) 的石英闪长斑岩、闪长玢岩和花岗闪长斑岩等,主要分布在包古图地区(沈远超等,1993)。另外,在西准噶尔地区一个显著的特点是有较多的蛇绿混杂岩发育,如达尔布特、白碱滩、唐巴勒、玛依勒及巴尔雷克等蛇绿混杂岩或蛇绿岩带(图 1b)(Feng et al., 1989Zhang et al., 1993Jian et al., 2005徐新等, 2006, 2010辜平阳等,2009张元元和郭召杰,2010;Yang et al., 2011)。这些蛇绿岩形态复杂,变形强烈,多沿走滑断裂分布,时代跨度大,从震旦纪到石炭纪均有出现。研究区出露的地层主体为奥陶系至石炭系火山-沉积地层,各地层单位多为断层接触(新疆维吾尔自治区地质矿产局,1993)。

3 蛇绿混杂岩地质特征及样品描述 3.1 岩体特征

玛依勒蛇绿混杂岩总体走向EW向,不连续延伸超过30km,由西向东渐宽呈三角状展布,由20余个大小不一的岩体构成,其多呈透镜状、串珠状和小岩株分布于中上志留统玛依拉山组和中泥盆统库鲁木迪组中(图 1c)。混杂岩带内各岩块均为构造接触界面,岩块原生构造被后期构造改造或置换,发育透入性构造面理,产状近于直立,成为堆叠在一起的构造杂岩体,但蛇绿岩的各组成单元出露仍较为齐全,主要包括超镁铁质岩石(蛇纹石岩和蛇纹石化纯橄岩等),辉长岩和辉长闪长岩脉以及枕状玄武岩,另外,伴生有放射虫硅质岩、硅质泥岩和凝灰岩等,其中辉长岩和辉长闪长岩脉主要呈岩脉穿插于蛇纹岩和蛇纹石化纯橄岩中,大量的溢流相枕状及块状玄武岩组成上部基性熔岩单元,玄武岩中枕状构造较为发育,也存在冷凝边、扭动构造和流动构造。

3.2 样品描述

由于超镁铁质岩石发生了强烈的蛇纹石化、滑石化和碳酸盐化,本次仅对弱蚀变的辉长岩和玄武岩进行取样分析。野外采集辉长岩和玄武岩样品共30余件,首先研碎手工挑选出杏仁体,再经过镜下仔细鉴定排除杏仁体含量高的玄武岩和后期异剥钙榴岩化的产物,最终挑选出用于岩石全分析的12件样品,包括7件玄武岩和5件辉长岩。这些样品均采自基岩露头,样品新鲜,采集位置避开了研究区内的接触带、蚀变带和断裂破碎带等。用于LA-ICP-MS锆石U-Pb定年的样品采自辉长岩(编号:08TW-XII-1),采样位置为N45°22′30″,E82°57′25″。

辉长岩表面风化色为灰绿色(局部为黑色),新鲜面为深绿色,辉长辉绿结构,局部具有堆晶结构,块状构造。岩石主要由基性斜长石(50%~60%)、普通辉石(20%~30%) 和角闪石(5%~10%) 组成。辉石、斜长石局部绢云母化、绿泥石化和绿帘石化(图 2a)。

图 2 辉长岩(a) 和玄武岩(b) 正交偏光显微照片 Fig. 2 Crossed polarized light micrographs of gabbros (a) and basalts (b)

玄武岩枕多为椭球体,表面光滑,大小为5×8cm~40×60cm,枕体边部分布有压扁或同向的杏仁体或气孔,向中心逐渐减少,外壳具有1~5cm的冷凝边,表面可见放射状裂纹或凹凸不平的球颗。岩石主要组成为斜长石(55%~65%),辉石(5%~15%),纤闪石(5%~10%),玄武玻璃(5%~10%) 及钛铁矿( < 1%) 等,偶见斜长石斑晶(图 2b)。

4 分析方法

主量元素在宜昌地质矿产研究所用X射线荧光光谱(XRF) 方法分析完成,XRF溶片法按照国家标准GB/T 14506.28-1993执行。元素分析误差小于2.5%,氧化物总量介于99.75%~100.25%。FeO用湿化学分析法单独测定完成,烧失量(LOI) 在烘箱中经1000℃高温烘烤90min后称重获得。微量元素在长安大学西部矿产资源与地质工程教育部重点实验室采用Thermo-X7电感耦合等离子体质谱仪进行样品测定,仪器工作参数:Power:1200w,Nebulizer gas:0.64 L/min,Auxiliary gas:0.80 L/min,Plasma gas:13 L/min。

激光剥蚀电感耦合等离子体质谱(LA-ICP-MS) 原位U-Pb定年在西北大学大陆动力学国家重点实验室完成。首先使用常规的重液浮选和电磁分离方法挑选出锆石,然后在双目镜下根据锆石颜色、自形程度、形态和透明度等特征初步分类,挑选出具有代表性的锆石,用环氧树脂固定,待其充分固化后抛光至锆石露出核部,进行锆石CL显微图像分析。锆石U-Pb同位素测定在西北大学大陆动力学国家重点实验室用德国MicroLas公司生产的GeoLas 200M激光剥蚀系统与Elan 6100DRC ICP-MS联机上进行测定,分析采用的激光斑束直径为30μm,激光脉冲为10Hz,能量为32~36mJ,激光剥蚀样品的深度为20~40μm。锆石年龄测定采用国际标准锆石91500作为外部标准物质。详细分析步骤和数据处理方法参见相关文献(Horn et al., 2000Ballard et al., 2001Košler et al., 2002袁洪林等,2003)。采用Glitter (ver4.0,Macquarie University) 序对锆石的同位素比值及元素含量进行计算。并按照Andersen Tom的方法(Andersen,2002)。用LAM-ICPMS Common Lead Correction (ver 3.15) 进行普通铅校正。年龄计算及谐和图采用Isoplot (ver 3.0) 完成(Ludwig, 1991, 1999)。

5 分析结果 5.1 锆石U-Pb年代学

蛇绿混杂岩中辉长岩样品(08TW-XII-1) 的锆石颗粒形状比较规则,粒径在100~150μm之间,锆石的CL图像显示大多数锆石具有较好的晶型,并显示明显的岩浆结晶环带,没有被后期改造的痕迹,个别的锆石晶体内部环带不发育,仅见稀疏的直纹条带(图 3a)。锆石的Th/U比值范围为0.3~1.0,均大于0.1(表 1),且Th、U之间具有良好的正相关关系,表明其为岩浆成因锆石(Claesson et al., 2000Fernando et al., 2003)。

图 3 玛依勒蛇绿混杂岩中辉长岩锆石CL图像(a) 及谐和曲线图(b) Fig. 3 CL images and U-Pb concordia plots of zircons for gabbros from the Mayile ophiolitic mélange

表 1 西准噶尔玛依勒蛇绿混杂岩中辉长岩(08TW-Ⅻ-1) LA-ICP-MS锆石U-Pb同位素分析结果 Table 1 LA-ICP-MS zircon U-Pb isotopic analysis of the gabbro (Sample 08TW-Ⅻ-1) for the Mayile ophiolitic mélange in the West Junggar

由于235U的衰变比238U快6.3倍,放射成因的207Pb在地球早期历史中更为丰富,而显生宙以来207Pb生成率很低,这种变化是显生宙锆石的207Pb计数速率低,而造成207Pb测定的误差较大,使得207Pb/206Pb和207Pb/235U比值可信度降低。因此,对于显生宙锆石,一般采用206Pb/238U年龄(Compston et al., 1992)。辉长岩锆石微区有效数据分析点共18个,206Pb/238U年龄范围在545~608Ma,最大的年龄误差12Ma,所有18个数据点集中分布在谐和曲线附近,其206Pb/238U年龄的加权平均值为572.2±9.2Ma,MSWD=1.04(95%置信度)(图 3b)。

5.2 主量元素

蛇绿混杂岩中辉长岩和玄武岩岩石化学分析结果及有关参数列于表 2。从表 2可以看出,玄武岩SiO2含量36.13%~45.98%,接近于MORB中SiO2含量(49.80%) 和达尔布特蛇绿岩中玄武岩(43.46%;刘希军等,2009),但低于Upper Troodos枕状熔岩(53.27%;Pearce,1975) 和Semail玄武岩(53.21%;Alabaster et al., 1982),Al2O3含量12.21%~14.03%,MgO为3.95%~5.27%,Mg#为32~68,略低于原生岩浆(Mg#=68~75;Wilson,1989),反映岩浆经历了一定程度的结晶分异作用。TiO2含量为1.65%~3.13%,明显高于IAB (0.58%~0.85%) 及MORB (1%~1.5%),而与加拿大Flin Flon带的Long Bay的OIB (1.35%~2.29%;Stern et al., 1995) 及克拉玛依OIB型枕状玄武岩(1.29%~2.48%;朱永峰等,2007) 相近。Na2O含量1.12%~5.27%,平均为3.0%,略低于碱性玄武岩的平均值(3.2%),K2O为0.03%~0.68%,Na2O>K2O,Na2O+K2O为1.16%~5.8%,与克拉玛依OIB型枕状玄武岩(4.33%~9.38%;朱永峰等,2007) 及阿尼玛卿蛇绿岩中OIB (2.2%~4.73%;郭安林等,2006) 相近。P2O5含量为0.17%~0.51%,平均为0.29%,与克拉玛依OIB型枕状玄武岩(平均为0.24%;朱永峰等,2007) 相一致。辉长岩相对于玄武岩,TiO2(0.06%~1.14%),P2O5(0.01%~0.03%) 及Na2O+K2O (0.2%~0.6%) 偏低,而MgO (5.33%~17.12%) 及Mg#(62~74) 偏高。在TAS图(图 4a) 中,几乎所有的样品均落在玄武岩区,个别的落在安山岩及玄武质安山岩区,另外,枕状熔岩均属于碱性系列,而侵入产出的岩脉为亚碱性,这与在抗蚀变元素图解Nb/Y-Zr/TiO2中投图结果一致(图 4b)。所有的样品投点落在克拉玛依OIB型枕状玄武岩区或者附近(图 4ab)。

图 4 玛依勒蛇绿混杂岩中玄武岩和辉长岩TAS图(a, 据Le Bas et al., 1986)和Nb/Y-Zr/TiO2图(b, 据Winchester and Floyd, 1977) Fig. 4 TAS (a,after Le Bas et al., 1986) and Nb/Y-Zr/TiO2 (b,Winchester and Floyd, 1977)for gabbros and basalts from the Mayile ophiolitic mélange in the West Junggar

表 2 西准噶尔玛依勒蛇绿混杂岩中玄武岩和辉长岩主量元素(wt%)、微量元素(×10-6) 分析结果及主要参数 Table 2 The concentration of major (wt%), trace elements (×10-6) and their parameters for the gabbros and basalts of the Mayile ophiolitic mélange in the West Junggar, Xinjiang
5.3 微量元素

蛇绿混杂岩中玄武岩稀土元素总量较高(∑REE=65.8×10-6~149.5×10-6),高于MORB (39.1×10-6),无明显Eu异常(Eu/Eu*=0.9~1),表明没有发生斜长石的分离结晶作用。在球粒陨石标准化曲线图(图 5a) 上,轻稀土(LREE) 略富集,重稀土(HREE) 相对略亏损且平坦,轻重稀土分馏较为明显((La/Yb)N=2.5~7.4)。各个样品REE配分模式相互平行,只有位置的高低,显示稀土分异程度相当,具有同源岩浆演化特征。总体上配分曲线高于E-MORB,而接近于OIB,与夏威夷(Xia et al., 2008) 和日喀则(Hofmann and Jochum, 1996) 海山玄武岩相似。辉长岩与玄武岩具有相似的REE配分模式,但前者REE总量相对较低(∑REE=3.9×10-6~60×10-6),并呈平坦型((La/Yb)N=0.5~2.3) 伴有弱正Eu异常(Eu/Eu*=0.8~1.5),可能和斜长石的堆晶作用有关。

图 5 球粒陨石标准化的稀土元素配分模式(a) 和原始地幔标准化的多元素蛛网图(球粒陨石和原始地幔标准值据Sun and McDonough, 1989) Fig. 5 Chondrite-normalized REE distribution patterns (a) and primitive mantle-normalized multi-elements spider diagram (b) (chondrite data and primitive mantle data after Sun and McDonough, 1989)

在微量元素蛛网图(图 5b) 中,玄武岩的大离子亲石元素(LILE) Rb、Ba、Th相对富集,K相对亏损,高场强元素(HFSE) Zr、Hf、Nb相对亏损,在辉长岩中更为显著,表明辉长岩可能形成于不同的构造环境。Sr在玄武岩中呈现负异常,而在辉长岩中呈现明显的正异常。玄武岩中高场强元素(HFSE) Nb/Ta比值为15.7~16.7,平均为16.1,略低于OIB (17.8,Sun and McDonough, 1989),而接近于原始地幔值(17.5±2.0),Zr/Hf比值为38.4~43.2,平均为41.6,略高于OIB和原始地幔(分别为35.9,36.3),但远高于大陆地壳值(Nb/Ta=12~13,Zr/Hf=11)。总体上,玄武岩样品的曲线与OIB形态基本一致。

6 讨论 6.1 形成时代

根据前人研究成果,本文对东、西准噶尔广泛分布的蛇绿混杂岩时、空分布做了简要总结(表 3)。从表 3可以看出,这些蛇绿混杂岩时代跨度较大,从震旦纪晚期至早二叠世均有发育,主要集中在奥陶世、志留世及泥盆世,唐巴勒和达尔布特蛇绿混杂岩的同位素年龄数据可信度较高,其代表的洋盆可能分别打开于震旦纪晚期-寒武纪初期和中泥盆世。前人采用不同的测试方法对玛依勒蛇绿混杂岩中的辉石岩、玄武岩等分别进行锆石SHRIMP和全岩Rb-Sr等时线测年(朱宝清等,1987aJian et al., 2005魏荣珠等,2010),认为其形成于中或晚志留世。另外,李红生(1994)还从玛依勒地区玛依勒组地层中发现中志留世放射虫。笔者等对其中的辉长岩进行锆石LA-ICP-MS测年获得年龄572.2±9.2Ma,属于早震旦纪,这些表明在玛依勒山一带可能至少存在两期洋壳,本文获得玛依勒蛇绿混杂岩年龄所代表的洋盆很可能在空间上和震旦纪在唐巴勒地区的洋盆(523.2±7.2Ma,Kwon et al., 1989) 是并存的。当然,也有可能572.2±9.2Ma的辉长岩代表着俯冲带环境下形成蛇绿岩组分,而~430Ma的板内玄武岩为后期保留在增生楔中的组分。另外,本文获得的年龄是早于唐巴勒蛇绿混杂岩及整个准噶尔地区蛇绿岩形成的年龄(表 3),是截至目前为止,在准噶尔乃至北疆地区报道的最古老的蛇绿混杂岩年龄。

表 3 准噶尔一带蛇绿混杂岩带年龄数据 Table 3 The ages of the ophiolitic mélange in the Junggar, Xinjiang
6.2 构造环境

已有研究表明,蛇绿岩可以形成于洋中脊、岛弧、弧前和弧后盆地,且大多数形成于消减带之上(Pearce et al., 1984Stern et al., 1989)。一般而言,玄武岩地球化学特征是讨论蛇绿混杂岩形成环境的最佳依据。玛依勒蛇绿混杂岩中的枕状玄武岩为碱性玄武岩(图 4a,b),岩石具有高Ti (TiO2=1.65%~3.13%)、高Fe (FeOT=8.93%~18.11%)、高Mg (MgO=3.95%~5.27%) 及高P (P2O5=0.17%~0.51%),Th/Ta比值相对较高(=1.1~1.9),LREE和HREE分异较为明显((La/Yb)N=2.5~7.4) 等特征,这些特征与OIB类似(张旗和周国庆,2001),这与REE球粒陨石模式图(图 5a) 和多元素蛛网图(图 5b) 显示相吻合,同时,也和克拉玛依OIB型枕状玄武岩(朱永峰等,2007) 及阿尼玛卿蛇绿岩中OIB (郭安林等,2006) 相近。

由于玄武岩样品遭受后期弱的碳酸盐化等蚀变,故选用抗蚀变元素如Zr、Y、Ti、Hf等进行构造环境判别。在Ti/100-Zr-3Y判别图(图 6a) 中,所有样品落入板内玄武岩区域,在Hf/3-Th-Ta判别图(图 6b) 中,样品表现出E-MORB及板内碱性玄武岩特征,这与TiO2-10×MnO-10×P2O5(图略) 投图结果相一致。由此可见,玛依勒蛇绿混杂岩中的枕状玄武岩可能形成于大洋板内的洋岛或海山环境。

图 6 玛依勒蛇绿混杂岩中玄武岩构造环境判别图 (a)-Ti/100-Zr-3×Y图解(据Pearce and Cann, 1973),A-岛弧拉斑玄武岩,B-MORB、岛弧拉斑玄武岩和钙碱性玄武岩,C-钙碱性玄武岩,D-板内玄武岩;(b)-Hf/3-Th-Ta图解(据Wood,1980),A-N-MORB,B-E-MORB和板内拉斑玄武岩,C-碱性板内玄武岩,D-火山弧玄武岩 Fig. 6 Tectonic setting discrimination diagram for the basalts in the Mayile ophiolitic mélange (a)-Ti/100-Zr-3×Y (after Pearce and Cann, 1973), A-island arc tholeiite basalt; B-MORB, island arc tholeiite and calc alkalic basalt; C-calc-alkalic basalt; D-with in plate basalt; (b)-Hf/3-Th-Ta (after Wood, 1980), A-N-MORB; B-E-MORB and within plate tholeiite basalt; C-alkalic within plate basalt; D-volcanic arc basalt

辉长岩的中有原生角闪石出现而玄武岩中未见(图 2ab);与玄武岩的富TiO2(1.54%~2.94%) 和P2O5(0.17%~0.45%) 不同的是,辉长岩极度贫TiO2(0.06%~0.14%) 和P2O5(0.01%~0.03%);辉长岩表现为平坦的稀土元素分配特征和Nb、Ta、Zr、Hf等高场强元素的明显负异常,与玄武岩的地球化学特征明显不同(图 5ab);另外,辉长岩中的Nb/La比值为0.23~0.38(除HC-1中的1.16外),而玄武岩中为1.14~1.39(除XW-2中的0.03外),前者明显低于后者。表明辉长岩在地球化学上具有明显不同于玄武岩,显示俯冲带信息。这一认识与Xu et al. (2012)最新通过矿物学和地球化学研究表明玛依勒蛇绿岩带显示俯冲相关的SSZ型的结论相吻合,另外,晚寒武-早志留世的岛弧侵入岩更是早古生代该地区处于俯冲环境的直接证据。

6.3 源区特征

微量元素比值可以有效区分原始岩浆演化过程受流体或地壳混染的程度,其地球化学特征指示源区性质。在Ta/Yb-Nb/Yb (图 7a) 和La/Yb-Nb/Yb图(图 7b) 中,玛依勒蛇绿混杂岩中玄武岩落在地幔序列中的E-MORB和OIB之间,表明这些元素主要受岩浆源区控制,后期过程(如流体或地壳混染) 对其影响较弱,这与较低的Nb/La比值(1.14~1.39) 相一致(夏林圻等,2007)。另外,样品的Zr/Nb=5.02~10.22,Th/La=0.08~0.15,Th/Nb=0.07~0.12,与EMI型洋岛玄武岩(OIB) 具有地球化学特征(Weaver,1991),表明其岩浆源区可能为EMI型富集地幔。

图 7 Ta/Yb-Nb/Yb (a) 和La/Yb-Nb/Yb (b) 图解(据朱永峰等,2007) 阴影区域表示不同类型大洋玄武岩(N-MORB,E-MORB,OIB) 相应元素变化范围(据Sun and McDonough, 1989) Fig. 7 Plots of Ta/Yb-Nb/Yb (a) and La/Yb-Nb/Yb (b) for basalts (after Zhu et al., 2007) Shaded areas indicate the range of oceanic basalts (N-MORB, E-MORB and OIB) (normalizing values after Sun and McDonough, 1989)

玛依勒蛇绿混杂岩中的玄武岩具有较低的(La/Yb)N、(Gd/Yb)N、(Dy/Yb)N、Sm/Yb比值(分别为2.5~7.4,1.5~2.6,1.2~1.7,1.4~2.8) 及相对较高的HREE含量(其HREE含量大于10倍球粒陨石),表明其原始岩浆应起源于岩石圈地幔尖晶石二辉橄榄岩的局部熔融(Chung,1999)。另外,在Ti/100-Zr-3×Y图(图 6a) 中样品几乎无一例外的落在的板内玄武岩区,显示板内富集趋势(Pearce and Norry, 1979)。因此我们推测这些玄武岩岩石成因与软流圈地幔关系密切,软流圈的上涌导致尖晶石相二辉橄榄岩地幔源区大比例部分熔融,是岩石圈-软流圈地幔相互作用的产物。

7 结论

通过对玛依勒蛇绿混杂岩中辉长岩和玄武岩开展LA-ICP-MS锆石U-Pb年代学、岩石学及地球化学研究,本为获得以下主要认识:

(1) 玛依勒蛇绿混杂岩的各组成单元出露仍较为齐全,主要包括超镁铁质岩石(蛇纹石岩和蛇纹石化纯橄岩等),辉长岩和辉长闪长岩脉以及枕状玄武岩,伴有放射虫硅质岩、硅质泥岩等。

(2) 辉长岩的LA-ICP-MS锆石年龄为572.2±9.2Ma,属于早震旦纪,该年龄是准噶尔乃至北疆地区报道的最古老的蛇绿混杂岩年龄。

(3) 玛依勒蛇绿混杂岩中的枕状玄武岩为碱性玄武岩,岩石具有高Ti (TiO2=1.65%~3.13%)、Fe (FeOT=8.93%~18.11%)、Mg (MgO=3.95%~5.27%) 及P (P2O5=0.17%~0.51%) 的特征,LREE和HREE分异较明显,其与洋岛玄武岩类似,可能形成于大洋板内的洋岛或海山环境。

(4) 辉长岩相对于玄武岩,TiO2(0.06%~1.14%),P2O5(0.01%~0.03%) 及Na2O+K2O (0.2%~0.6%) 偏低,而MgO (5.33%~17.12%) 及Mg#(62~74) 偏高,属于亚碱性系列。可能形成于俯冲带环境。

(5) 玛依勒蛇绿混杂岩中玄武岩与EMI型洋岛玄武岩具有相似的地球化学特征,表明其岩浆源区可能为EMI型富集地幔。岩石成因与软流圈地幔关系密切,软流圈的上涌导致尖晶石相二辉橄榄岩地幔源区大比例部分熔融,是岩石圈-软流圈地幔相互作用的产物。

致谢 真诚感谢审稿专家对本文的认真细致的审阅和修改。
参考文献
[] Alabaster T, Pearce JA, Malpas J. 1982. The volcanic stratigraphy and petrogenesis of the Oman ophiolite complex. Contributions to Mineralogy and Petrology, 81(3): 168–183. DOI:10.1007/BF00371294
[] Andersen T. 2002. Correction of common lead in U-Pb analyses that do not report 204Pb. Chemical Geology, 192(1-2): 59–79. DOI:10.1016/S0009-2541(02)00195-X
[] Ballard JR, Palin JM, Williams IS, Campbell IH, Faunes A. 2001. Two ages of porphyry intrusion resolved for the super-giant Chuquicamata copper deposit of northern Chile by ELA-ICP-MS and SHRIMP. Geology, 29(5): 383–386. DOI:10.1130/0091-7613(2001)029<0383:TAOPIR>2.0.CO;2
[] Bureau of Geology and Mineral Resources of Xinjiang (BGMRX). 1993. Regional Geology of Xinjiang Uygur Autonomous Region. Beijing: Geological Publishing House: 442-504.
[] Chen B, Jahn BM. 2004. Genesis of post-collisional granitoids and basement nature of the Junggar Terrane, NW China: Nd-Sr isotope and trace element evidence. Journal of Asian Earth Sciences, 23(5): 691–703. DOI:10.1016/S1367-9120(03)00118-4
[] Chen B, Zhu YF. 2010. Petrology and geochemistry of gabbro in Baikouquan, Keramay (Xinjiang, NW China): Implication of magmatic evolution. Acta Petrologica Sinica, 26(8): 2287–2298.
[] Chen JF, Han BF, Ji JQ, et al. 2010. Zircon U-Pb ages and tectonic implications of Paleozoic plutons in northern West Junggar. North Xinjiang, China. Lithos, 115(1-4): 137–152.
[] Chen JF, Han BF, Zhang L. 2010. Geochemistry, Sr-Nd isotopes and tectonic implications of two generations of Late Paleozoic plutons in northern West Junggar, Northwest China. Acta Petrologica Sinica, 26(8): 2317–2335.
[] Chen S, Guo ZJ. 2010. Time constraints, tectonic setting of Dalabute ophiolitic complex and its significance for Late Paleozoic tectonic evolution in West Junggar. Acta Petrologica Sinica, 26(8): 2336–2344.
[] Chung SL. 1999. Trace element and isotope characteristics of Cenozoic basalts around the Tanlu Fault with implications for the eastern plate boundary between north and south China. The Journal of Geology, 107(3): 301–312. DOI:10.1086/314348
[] Claesson S, Vetrin V, Bayanova T. 2000. U-Pb zircon ages from a Devonian carbonatite dyke, Kola peninsula, Russia: A record of geological evolution from the Archaean to the Palaeozoic. Lithos, 51(1-2): 95–108. DOI:10.1016/S0024-4937(99)00076-6
[] Compston W, Williams IS, Kirschvink JL. 1992. Zircon U-Pb ages for the Early Cambrian time-scale. Journal of the Geological Society, 149(2): 171–184. DOI:10.1144/gsjgs.149.2.0171
[] Fan Y, Zhou TF, Yuan F, Tan LG, Cooke D, Meffre S, Yang WP, He LX. 2007. LA-ICP MS zircon age of Tasite pluton in Sawuer region of west Junggar, Xinjiang. Acta Petrologica Sinica, 23(8): 1901–1908.
[] Feng Y, Coleman RG, Tilton G, Xiao X. 1989. Tectonic evolution of the West Junggar region, Xinjiang, China. Tectonics, 8(4): 729–752. DOI:10.1029/TC008i004p00729
[] Feng YM. 1987. Characteristics of ancient plate tectonics in West Junggar. Bulletin of Xi'an Institute Geology and Minerals Resources, Chinese Academy of Geological Sciences, 18(4): 141–160.
[] Fernando C, John MH, Paul WHO, Peter K. 2003. Atlas of zircon textures. Reviews in Mineralogy and Geochemistry, 53(1): 469–500. DOI:10.2113/0530469
[] Gao SL, He ZL, Zhou ZY. 2006. Geochemical characteristics of the Karamay granitoids and their significance in West Junggar, Xinjiang. Xinjiang Geology, 24(2): 125–130.
[] Geng HY, Sun M, Yuan C, Xiao WJ, Xian WS, Zhao GC, Zhang LF, Wong K, Wu FY. 2009. Geochemical, Sr-Nd and zircon U-Pb-Hf isotopic studies of Late Carboniferous magmatism in the West Junggar, Xinjiang: Implications for ridge subduction?. Chemical Geology, 266(3-4): 364–389. DOI:10.1016/j.chemgeo.2009.07.001
[] Gu PY, Li YJ, Zhang B, Tong LL, Wang JN. 2009. LA-ICP-MS zircon U-Pb dating of gabbro in the Darbut ophiolite, western Junggar, China. Acta Petrologica Sinica, 25(6): 1364–1372.
[] Guo AL, Zhang GW, Sun YG, Zheng JK, Liu Y, Wang JQ. 2006. Geochemistry and apatial distribution of OIB and MORB in A' nymaqen ophiolite zone: Evidence of Majixueshan ancient ridge-centered hotspot. Science in China (Series D), 36(7): 618–629.
[] Han BF, Ji JQ, Song B, Chen LH, Zhang L. 2006. Late Paleozoic vertical growth of continental crust around the Junggar Basin, Xinjiang, China (Part Ⅰ): Timing of post-collisional plutonism. Acta Petrologica Sinica, 22(5): 1077–1086.
[] Han BF, Guo ZJ, He GQ. 2010. Timing of major suture zones in North Xinjiang, China: Constraints from stitching plutons. Acta Petrologica Sinica, 26(8): 2233–2246.
[] Han BF, Guo ZJ, Zhang ZC, Zhang L, Chen JF, Song B. 2010. Age, geochemistry, and tectonic implications of a Late Paleozoic stitching pluton in the North Tian Shan suture zone, Western China. Geological Society of America Bulletin, 122(3-4): 627–640. DOI:10.1130/B26491.1
[] Han S, Dong JQ, Yu FS, Jia XQ. 2004. Trace element geochemistry of the opiolite from Mayila Mountain-Saleinohai of West Junggar, Xinjiang. Xinjiang Geology, 22(3): 290–295.
[] He GQ, Li MS. 2001. Significance of paleostructure and paleogeography of Ordovician-Silurian rock associations in northern Xinjiang, China. Acta Scientiarum Naturalium University Pekinensis, 37(1): 99–110.
[] He GQ, Li MS, Jia JD, Zhou H. 2001. A discussion on age and tectonic significance of ophiolite in eastern Junggar, Xinjiang. Acta Scientiarum Naturalium Universitatis Pekinensis, 37(6): 852–858.
[] He GQ, Liu JB, Zhang YQ, Xu X. 2007. Keramay ophiolitic mélange formed during Early Paleozoic in western Junggar basin. Acta Petrologica Sinica, 23(7): 1573–1576.
[] Hofmann AW, Jochum KP. 1996. Source characteristics derived from very incompatible trace elements in Mauna Loa and Mauna Kea basalts, Hawaii Scientific Drilling Project. Journal of Geophysical Research, 101(B5): 11831–11839. DOI:10.1029/95JB03701
[] Horn I, Rudnick RL, Mcdonough WF. 2000. Precise elemental and isotope ratio determination by simultaneous solution nebulization and laser ablation-ICP-MS: Application to U-Pb geochronology. Chemical Geology, 167: 405–425. DOI:10.1016/S0009-2541(00)00229-1
[] Huang JH, Jin ZD, Li FC. 1999. Age determination and Sm-Nd isotopic composition of the Hongguleleng ophiolite, Xinjiang. Chinese Science Bulletin, 44(9): 1004–1007.
[] Jahn BM, Wu FY, Chen B. 2000. Granitoids of the Central Asian Orogenic Belt and continental growth in the Phanerozoic. Transactions of the Royal Society of Edinburgh: Earth Sciences, 91(1-2): 181–193. DOI:10.1017/S0263593300007367
[] Jian P, Liu DY, Zhang Q, Zhang FQ, Shi YR, Shi GH, Zhang LQ, Tao H. 2003. SHRIMP dating of ophiolite and leucocratic rocks within ophiolite. Earth Science Frontiers, 10(4): 439–456.
[] Jian P, Liu DY, Shi YR and Zhang FQ. 2005. SHRIMP dating of SSZ ophiolites from northern Xinjiang Province, China: Implications for generation of oceanic crust in the central Asian orogenic belt. In: Sklyarov EV (ed.). Structural and Tectonic Correlation across the Central Asian Orogenic Collage: Northeastern Segment. Guidebook and Abstract Volume of the Siberian Workshop IGCP-480, 1-246
[] Košler J, Fonneland H, Sylvester P, Tubrett M, Pedersen RB. 2002. U-Pb dating of detrital zircons for sediment provenance studies: A comparison of laser ablation ICPMS and SIMS techniques. Chemical Geology, 182(2-4): 605–618. DOI:10.1016/S0009-2541(01)00341-2
[] Kwon ST, Tilton GR, Coleman RG, Feng Y. 1989. Isotopic studies bearing on the tectonics of the West Junggar region, Xinjiang, China. Tectonics, 8(4): 719–727. DOI:10.1029/TC008i004p00719
[] Le Bas MJ, Le Maitre RW, Streckeisen A, Zanettin B. 1986. A chemical classification of volcanic rocks based on the total alkali-silica diagram. Journal of Petrology, 27(3): 745–750. DOI:10.1093/petrology/27.3.745
[] Lei M, Zhao ZD, Hou QY, Zhang HF, Xu JF, Chen YL, Zhang BR, Liu XJ. 2008. Geochemical and Sr-Nd-Pb isotopic characteristics of the Dalabute ophiolite, Xinjiang: Comparison between the Paleo-Asian ocean and the Tethyan mantle domains. Acta Petrologica Sinica, 24(4): 661–672.
[] Li HS. 1994. Middle Silurian radiolarian Kerhada, Xinjiang. Acta Micropalaeontologica Sinica, 11(2): 259–272.
[] Li JY. 1991. Early Paleozoic evolution of lithosphere plate, East Junggar, Xinjiang. Bulletin of the Chinese Academy of Geological Sciences, 12(2): 1–12.
[] Li JY. 2004. Late Neoproterozoic and Paleozoic tectonic framework and evolution of eastern Xinjiang, NW China. Geological Review, 50(3): 304–322.
[] Liu W and Zhang XB. 1993. The characteristics and geological significance of Ulungur-Zhaisangpo tectonic mélange belt. In: Tu GC (ed.). New Improvement of Solid Geosciences in Northern Xinjiang. Beijing: Science Press, 217-228 (in Chinese)
[] Liu XJ, Xu JF, Wang SQ, Hou QY, Bai ZH, Lei M. 2009. Geochemistry and dating of E-MORB type mafic rocks from Dalabute ophiolite in West Junggar, Xinjiang and geological implications. Acta Petrologica Sinica, 25(6): 1373–1389.
[] Ludwig KR. 1991. Isoplot-A plotting and regression program for radiogenic-isotope data. US Geological Survey Open-File Report, 39: 91–445.
[] Ludwig KR. 1999. Using Isop lot/EX, version 2, a geochronological toolkit for Microsoft Excel. Berkeley Geochronological Center Special Publication (la), 47
[] Peng GY. 1996. Podiform chromite and associated ophiolitic rocks in West Junggar, Xinjiang, NW China. Ph. D. Dissertation. Washington: George Washington University, 1-369
[] Pearce JA, Cann JR. 1973. Tectonic setting of basic volcanic rocks determined using trace element analyses. Earth and Planetary Sciences Letters, 19: 290–300. DOI:10.1016/0012-821X(73)90129-5
[] Pearce JA, Norry MJ. 1979. Petrogenetic implications of Ti, Zr, Y, and Nb variations in volcanic rocks. Contrib. Mineral. Petrol., 69(1): 33–47. DOI:10.1007/BF00375192
[] Pearce JA, Lippard SJ, Roberts S. 1984. Characteristics and tectonic significance of supra-subduction zone ophiolites. In: Kokelaar BP and Howells MF (eds.). Marginal Basin Geology. Geological Society, London, Special Publication, 16(1): 77–94. DOI:10.1144/GSL.SP.1984.016.01.06
[] Shu LS, Wang YZ. 2003. Late Devonian-Early Carboniferous radiolarian fossils from siliceous rocks of the Kelameili ophiolite, Xinjiang. Geological Review, 49(4): 408–412.
[] Stern RA, Syme EC, Lucas SB. 1995. Geochemistry of 1. 9Ga MORB-and OIB-like basalts from the Amisk collage, Flin Flon Belt, Canada: Evidence for an intra-oceanic origin. Geochimica et Cosmochimica Acta, 59(15): 3131–3154.
[] Stern RJ, Bloomer SH, Lin PN, Smoot NC. 1989. Submarine arc volcanism in the southern Mariana Arc as an ophiolite analogue. Tectonophysics, 168(1-3): 151–170. DOI:10.1016/0040-1951(89)90374-0
[] Su YP, Tang HF, Hou GS, Liu CQ. 2006. Geochemistry of aluminous A-type granites along Darabut tectonic belt in West Junggar, Xinjiang. Geochimica, 35(1): 55–67.
[] Sun SS, Mcdonough WF. 1989. Chemical and isotopic systematics of oceanic basalts: Implications for mantle composition and processes. In: Sauders AD and Norry MJ (eds). Magmatism in the Ocean Basins. Spec. Publ. Geol. Soc. Lond., 42: 313–345.
[] Tang GJ, Wang Q, Wyman DA, Li ZX, Zhao ZH, Jia XH, Jiang ZQ. 2010. Ridge subduction and crustal growth in the Central Asian Orogenic Belt: Evidence from Late Carboniferous adakites and high-Mg diorites in the western Junggar region, northern Xinjiang (west China). Chemical Geology, 277(3-4): 281–300. DOI:10.1016/j.chemgeo.2010.08.012
[] Tang HF, Su YP, Liu CQ, Hou GS, Wang YB. 2007. Zircon U-Pb age of the plagiogranite in Kalamaili belt, northern Xinjiang and its tectonic implications. Geotectonica et Metallogenia, 31(1): 110–117.
[] Wang BY, Jiang CY, Li YJ, Wu HE, Xia ZD, Lu RH. 2009. Geochemistry and tectonic implications of Karamaili ophiolite in East Junggar of Xinjiang. Journal of Mineralogy and Petrology, 29(3): 74–82.
[] Wang ZH, Sun S, Li JL, Hou QL, Qin KZ, Xiao WJ, Hao J. 2003. Paleozoic tectonic evolution of the northern Xinjiang, China: Geochemical and geochronological constraints from the ophiolites. Tectonics, 22(2): 1014–1029.
[] Weaver BL. 1991. The origin of ocean island basalt end-member compositions: Trace element and isotopic constraints. Earth and Planetary Science Letters, 104(2-4): 381–397. DOI:10.1016/0012-821X(91)90217-6
[] Wei RZ. 2010. The Mayileshang pillow lavas (western Junggar, Xinjiang) and their tectonic implications: Constraints from the geological and geochemical characteristics and Rb-Sr isochron ages. Xinjiang Geology, 28(3): 229–235.
[] Wilson BM. 1989. Igneous Petrogenesis. London: Unwin Hyman: 1-25.
[] Winchester JA, Floyd PA. 1977. Geochemical discrimination of different magma series and their differentiation products using immobile elements. Chemical Geology, 20: 325–343. DOI:10.1016/0009-2541(77)90057-2
[] Windley BF, Alexeiev D, Xiao WJ, Kroner A, Badarch G. 2007. Tectonic models for accretion of the Central Asian Orogenic Belt. Journal of the Geological Society, 164(1): 31–47. DOI:10.1144/0016-76492006-022
[] Wood DA. 1980. The application of a Th-Hf-Ta diagram to problems of tectonomagmatic classification and to establishing the nature of crustal contamination of basaltic lavas of the British Tertiary volcanic province. Earth and Planetary Science Letters, 50(1): 11–30. DOI:10.1016/0012-821X(80)90116-8
[] Xia B, Chen GW, Wang R, Wang Q. 2008. Seamount volcanism associated with the Xigaze ophiolite, Southern Tibet. Journal of Asian Earth Sciences, 32(5-6): 396–405. DOI:10.1016/j.jseaes.2007.11.008
[] Xia LQ, Xia ZC, Xu XY, Li XM, Ma ZP. 2007. The discrimination between continental basalt and island arc basalt based on geochemical method. Acta Petrologica et Mineralogica, 26(1): 77–89.
[] Xiao WJ, Windley BF, Yan QR, Qin KZ, Chen HL, Yuan C, Sun M, Li JL, Sun S. 2006. SHRIMP zircon age of the Aermantai ophiolite in the North Xinjiang area, China and its tectonic implications. Acta Geologica Sinica, 80(1): 32–37.
[] Xiao WJ, Han CM, Yuan C, Sun M, Lin SF, Chen HL, Li ZL, Li JL, Sun S. 2008. Middle Cambrian to Permian subduction-related accretionary orogenesis of northern Xinjiang, NW China: Implications for the tectonic evolution of Central Asia. Journal of Asian Earth Sciences, 32(2-4): 102–117. DOI:10.1016/j.jseaes.2007.10.008
[] Xiao WJ, Kröner A, Windley BF. 2009. Geodynamic evolution of Central Asia in the Paleozoic and Mesozoic. International Journal of Earth Sciences, 98(6): 1185–1188. DOI:10.1007/s00531-009-0418-4
[] Xiao XC, Tang YQ, Li JY, Zhao M, Feng YM and Zhu BQ. 1991. Tectonic evolution of the southern margin of the Paleo-Asian composite megasuture. In: Xiao XC and Tang YQ (eds.). Tectonic Evolution of the Southern Margin of the Paleo-Asian Composite Megasuture. Beijing: Beijing Science and Technology Publishing House, 1-29 (in Chinese)
[] Xiao XC, Tang YQ, Feng YM, Zhu BQ, Li JY, Zhao M. 1992. Tectonic Evolution of Northern Xinjiang and Its Adjacent Regions. Beijing: Geological Publishing House: 1-169.
[] Xu X, He GQ, Li HQ, Ding TF, Liu XY, Mei SW. 2006. Basic characteristics of the Karamay ophiolitic mélange, Xinjiang and its zircon SHRIMP dating. Geology in China, 33(3): 470–475.
[] Xu X, Zhou KF, Wang Y. 2010. Study on extinction of the remnant oceanic basin and tectonic setting of West Junggar during Late Paleozoic. Acta Petrologica Sinica, 26(11): 3206–3214.
[] Xu Z, Han BF, Ren R, Zhou YZ, Zhang L, Chen JF, Su L, Li XH, Liu DY. 2012. Ultramafic-mafic mélange, island arc and post-collisional intrusions in the Mayile Mountain, West Junggar, China: Implications for Paleozoic intra-oceanic subduction-accretion process. Lithos, 132.
[] Yang GX, Li YJ, Gu PY, Yang BK, Tong LL, Zhang HW. 2012. Geochronological and geochemical study of the Darbut ophiolitic complex in the West Junggar (NW China): Implications for petrogenesis and tectonic evolution. Gondwana Research, 21(4): 1037–1049. DOI:10.1016/j.gr.2011.07.029
[] Yin JY, Yuan C, Sun M, Long XP, Zhao GC, Wong KP, Geng HY, Cai KD. 2010. Late Carboniferous high-Mg dioritic dikes in Western Junggar, NW China: Geochemical features, petrogenesis and tectonic implications. Gondwana Research, 17(1): 145–152. DOI:10.1016/j.gr.2009.05.011
[] Yuan HL, Wu FY, Gao S, Liu XM, Xu P, Sun DY. 2003. LA-ICP-MS zircon U-Pb age and REE of Cenozoic pluton in NE China. Chinese Science Bulletin, 48(14): 1511–1520.
[] Zhang C, Huang X. 1992. The ages and tectonic settings of ophiolites in West Junggar, Xinjiang. Geological Review, 38(6): 509–524.
[] Zhang C, Zhai MG, Allen MB, Saunders AD, Wang GR, Huang X. 1993. Implications of Palaeozoic ophiolites from Western Junggar, NW China, for the tectonics of Central Asia. Journal of the Geological Society, 150(3): 551–561. DOI:10.1144/gsjgs.150.3.0551
[] Zhang CL, Li ZX, Li XH, Xu YG, Zhou G, Ye HM. 2010. A Permian large igneous province in Tarim and Central Asian orogenic belt, NW China: Results of a ca. 275Ma mantle plume? Geological Society of America Bulletin, 122(11-12): 2020–2040. DOI:10.1130/B30007.1
[] Zhang HX, Niu HC, Terada K, Yu XY, Sato H, Ito J. 2003. Zircon SHRIMP U-Pb dating on plagiogranite from the Kuerti ophiolite in Altay, North Xinjiang. Chinese Science Bulletin, 48(12): 1350–1354.
[] Zhang LC, Wan B, Jiao XJ, Zhang R. 2006. Characteristics and geological significance of adakitic rocks in copper-bearing porphyry in Baogutu, western Junggar. Geology in China, 33(3): 626–631.
[] Zhang LF. 1997. 40Ar/39Ar dating of Tangbale blueschist in West Junggar, Xinjiang and its tectonic implications. Chinese Science Bulletin, 42(20): 2178–2181.
[] Zhang Q, Zhou GQ. 2001. Ophiolite of China. Beijing: Science Press, 1.
[] Zhang YY, Guo ZJ. 2010. New constraints on formation ages of ophiolites in northern Junggar and comparative study on their connection. Acta Petrologica Sinica, 26(2): 421–430.
[] Zhou TF, Yuan F, Fan Y, Zhang DY, Cooke D, Zhao GC. 2008. Granites in the Sawuer region of the West Junggar, Xinjiang Province, China: Geochronological and geochemical characteristics and their geodynamic significance. Lithos, 106(3-4): 191–206. DOI:10.1016/j.lithos.2008.06.014
[] Zhu BQ, Wang LS and Wang LX. 1987a. Paleozoic Era ophiolite of southwest part in western Junggar, Xinjiang, China. Bull. Xi'an Inst. Geol. Min. Res., Chinese Acad. Geol. Sci., (17): 3-64 (in Chinese with English abstract)
[] Zhu BQ, Feng YM, Ye LH. 1987b. Paleozoic Ophiolite and Its Geological Implications in the West Junggar, Xinjiang. Beijing: Geological Publishing House: 19–28.
[] Zhu YF, Zhang LF, Gu LB, Guo X, Zhou J. 2005. The zircon SHRIMP chronology and trace element geochemistry of the Carboniferous volcanic rocks in western Tianshan Mountains. Chinese Science Bulletin, 50(19): 2201–2212. DOI:10.1007/BF03182672
[] Zhu YF, Xu X. 2006. The discovery of Early Ordovician ophiolite mélange in Taerbahatai Mts. , Xinjiang, NW China. Acta Petrologica Sinica, 22(12): 2833–2842.
[] Zhu YF, Xu X. 2007. Exsolution texture of two-pyroxenes in lherzolite from Baijiantan ophiolitic mélange, western Junggar, China. Acta Petrologica Sinica, 23(5): 1075–1086.
[] Zhu YF, Xu X, Wei SN, Song B, Guo X. 2007. Geochemistry and tectonic significance of OIB-type pillow basalts in western Mts. of Karamay City (western Junggar), NW China. Acta Petrologica Sinica, 23(7): 1739–1748.
[] Zhu YF, Xu X, Chen B, Xue YX. 2008. Dolomite marble and garnet amphibolite in the ophiolitic melange in western Junggar: Relics of the Early Paleozoic oceanic crust and its deep subduction. Acta Petrologica Sinica, 24(12): 2676–2777.
[] 陈博, 朱永峰. 2010. 新疆克拉玛依百口泉蛇绿混杂岩中辉长岩岩石学和地球化学研究. 岩石学报, 26(8): 2287–2298.
[] 陈家富, 韩宝福, 张磊. 2010. 西准噶尔北部晚古生代两期侵入岩的地球化学、Sr-Nd同位素特征及其地质意义. 岩石学报, 26(8): 2317–2335.
[] 陈石, 郭召杰. 2010. 达拉布特蛇绿岩带的时限和属性以及对西准噶尔晚古生代构造演化的讨论. 岩石学报, 26(8): 2336–2344.
[] 范裕, 周涛发, 袁峰, 谭绿贵, CookeD, MeffreS, 杨文平, 何立新. 2007. 新疆西准噶尔地区塔斯特岩体锆石LA-ICPMS年龄及其意义. 岩石学报, 23(8): 1901–1908.
[] 冯益民. 1987. 西准噶尔古板块构造特征. 中国地质科学院西安地质矿产研究所所刊, 18(4): 141–160.
[] 高山林, 何治亮, 周祖翼. 2006. 西准噶尔克拉玛依花岗岩体地球化学特征及其意义. 新疆地质, 24(2): 125–130.
[] 辜平阳, 李永军, 张兵, 佟丽莉, 王军年. 2009. 西准达尔布特蛇绿岩中辉长岩LA-ICP-MS锆石U-Pb测年. 岩石学报, 25(6): 1364–1372.
[] 郭安林, 张国伟, 孙延贵, 郑健康, 刘晔, 王建其. 2006. 阿尼玛卿蛇绿岩带OIB和MORB的地球化学及空间分布特征:玛积雪山古洋脊热点构造证据. 中国科学(D辑), 36(7): 618–629.
[] 韩宝福, 季建清, 宋彪, 陈立辉, 张磊. 2006. 新疆准噶尔晚古生代陆壳垂向生长(Ⅰ):后碰撞深成岩浆活动的时限. 岩石学报, 22(5): 1077–1086.
[] 韩宝福, 郭召杰, 何国琦. 2010. "钉合岩体"与新疆北部主要缝合带的形成时限. 岩石学报, 26(8): 2233–2246.
[] 韩松, 董金泉, 于福生, 贾秀琴. 2004. 新疆西准噶尔玛依拉山-萨雷诺海蛇绿岩岩石地球化学特征. 新疆地质, 22(3): 290–295.
[] 何国琦, 李茂松. 2001. 中国新疆北部奥陶-志留系岩石组合的古构造、古地理意义. 北京大学学报(自然科学版), 37(1): 99–110.
[] 何国琦, 李茂松, 贾进斗, 周辉. 2001. 论新疆东准噶尔蛇绿岩的时代及其意义. 北京大学学报(自然科学版), 37(6): 852–858.
[] 何国琦, 刘建波, 张越迁, 徐新. 2007. 准噶尔盆地西缘克拉玛依早古生代蛇绿混杂岩带的厘定. 岩石学报, 23(7): 1573–1576.
[] 黄建华, 金章东, 李富春. 1999. 洪古勒楞蛇绿岩Sm-Nd同位素特征及时代界定. 科学通报, 44(9): 1004–1007.
[] 简平, 刘敦一, 张旗, 张福勤, 石玉若, 施光海, 张履桥, 陶华. 2003. 蛇绿岩及蛇绿岩中浅色岩的SHRIMP U-Pb测年. 地学前缘, 10(4): 439–456.
[] 雷敏, 赵志丹, 侯青叶, 张宏飞, 许继峰, 陈岳龙, 张本仁, 刘希军. 2008. 新疆达拉布特蛇绿岩带玄武岩地球化学特征:古亚洲洋与特提斯洋的对比. 岩石学报, 24(4): 661–672.
[] 李红生. 1994. 新疆克尔哈达中志留世放射虫. 微体古生物学报, 11(2): 259–272.
[] 李锦轶. 1991. 试论新疆东准噶尔早古生代岩石圈板块构造演化. 中国地质科学院院报, 12(2): 1–12.
[] 李锦轶. 2004. 新疆东部新元古代晚期和古生代构造格局及其演变. 地质论评, 50(3): 304–322.
[] 刘伟, 张湘炳. 1993.乌伦古-斋桑泊构造杂岩带特征及其地质意义.见:涂光炽主编.新疆北部固体地球科学新进展.北京:科学出版社, 217-228
[] 刘希军, 许继峰, 王树庆, 侯青叶, 白正华, 雷敏. 2009. 新疆西准噶尔达拉布特蛇绿岩E-MORB型镁铁质岩的地球化学、年代学及其地质意义. 岩石学报, 25(6): 1373–1389.
[] 舒良树, 王玉净. 2003. 新疆卡拉麦里蛇绿岩带中硅质岩的放射虫化石. 地质论评, 49(4): 408–412.
[] 苏玉平, 唐红峰, 侯广顺, 刘丛强. 2006. 新疆西准噶尔达拉布特构造带铝质A型花岗岩的地球化学研究. 地球化学, 35(1): 55–67.
[] 唐红峰, 苏玉平, 刘丛强, 侯广顺, 王彦斌. 2007. 新疆北部卡拉麦里斜长花岗岩的锆石U-Pb年龄及其构造意义. 大地构造与成矿学, 31(1): 110–117.
[] 汪帮耀, 姜常义, 李永军, 吴宏恩, 夏昭德, 卢荣辉. 2009. 新疆东准噶尔卡拉麦里蛇绿岩的地球化学特征及大地构造意义. 矿物岩石, 29(3): 74–82.
[] 魏荣珠. 2010. 西准噶尔玛依勒山枕状熔岩地质特征及大地构造意义. 新疆地质, 28(3): 229–235.
[] 夏林圻, 夏祖春, 徐学义, 李向民, 马中平. 2007. 利用地球化学方法判别大陆玄武岩和岛弧玄武岩. 岩石矿物学杂志, 26(1): 77–89.
[] 肖文交, WindleyBF, 闫全人, 秦克章, 陈汉林, 袁超, 孙敏, 李继亮, 孙枢. 2006. 北疆地区阿尔曼太蛇绿岩锆石SHRIMP年龄及其大地构造意义. 地质学报, 80(1): 32–37.
[] 肖序常, 汤耀庆, 李锦轶, 赵民, 冯益民, 朱宝清. 1991.古中亚复合巨型缝合带南缘构造演化.见:肖序常, 汤耀庆主编.古中亚复合巨型缝合带南缘构造演化.北京:科学技术出版社, 1-29
[] 肖序常, 汤耀庆, 冯益民, 朱宝清, 李锦轶, 赵民. 1992. 新疆北部及其邻区大地构造. 北京: 地质出版社: 1-169.
[] 新疆维吾尔自治区地质矿产局. 1993. 新疆维吾尔族自治区区域地质志. 北京: 地质出版社: 442-504.
[] 徐新, 何国琦, 李华芹, 丁天府, 刘兴义, 梅绍武. 2006. 克拉玛依蛇绿混杂岩带的基本特征和锆石SHRIMP年龄信息. 中国地质, 33(3): 470–475.
[] 徐新, 周可法, 王煜. 2010. 西准噶尔晚古生代残余洋盆消亡时间与构造背景研究. 岩石学报, 26(11): 3206–3214.
[] 袁洪林, 吴福元, 高山, 柳小明, 徐平, 孙德有. 2003. 东北地区新生代侵入体的锆石激光探针U-Pb年龄测定与稀土元素成分分析. 科学通报, 48(14): 1511–1520.
[] 张驰, 黄萱. 1992. 新疆西准噶尔蛇绿岩形成时代和环境的探讨. 地质论评, 38(6): 509–524.
[] 张海祥, 牛贺才, TeradaK, 于学元, SatoH, ItoJ. 2003. 新疆北部阿尔泰地区库尔提蛇绿岩中斜长花岗岩的SHRIMP年代学. 科学通报, 48(12): 1350–1354.
[] 张立飞. 1997. 新疆西准噶尔唐巴勒蓝片岩40Ar/39Ar年龄及其地质意义. 科学通报, 42(20): 2178–2181.
[] 张连昌, 万博, 焦学军, 张锐. 2006. 西准包古图含铜斑岩的埃达克岩特征及其地质意义. 中国地质, 33(3): 626–631.
[] 张旗, 周国庆. 2001. 中国蛇绿岩. 北京: 科学出版社: 1-182.
[] 张元元, 郭召杰. 2010. 准噶尔北部蛇绿岩形成时限新证据及其东、西准噶尔蛇绿岩的对比研究. 岩石学报, 26(2): 421–430.
[] 朱宝清, 王来生, 王连晓. 1987a. 西准噶尔西南地区古生代蛇绿岩. 中国地质科学院西安地质矿产研究所所刊(17): 3–64.
[] 朱宝清, 冯益民, 叶良和. 1987b. 新疆西准噶尔古生代蛇绿岩及其地质意义. 北京: 地质出版社: 19-28.
[] 朱永峰, 徐新. 2006. 新疆塔尔巴哈台山发现早奥陶世蛇绿混杂岩. 岩石学报, 22(12): 2833–2842.
[] 朱永峰, 徐新. 2007. 西准噶尔白碱滩二辉橄榄岩中两种辉石的出溶结构及其地质意义. 岩石学报, 23(5): 1075–1086.
[] 朱永峰, 徐新, 魏少妮, 宋彪, 郭璇. 2007. 西准噶尔克拉玛依OIB型枕状玄武岩地球化学及其地质意义研究. 岩石学报, 23(7): 1739–1748.
[] 朱永峰, 徐新, 陈博, 薛云兴. 2008. 西准噶尔蛇绿混杂岩中的白云石大理岩和石榴角闪岩:早古生代残余洋壳深俯冲的证据. 岩石学报, 24(12): 2676–2777.