岩石学报  2013, Vol. 29 Issue (8): 2719-2730   PDF    
内蒙西乌旗白音布拉格蛇绿岩地球化学特征
李英杰, 王金芳, 李红阳, 董培培, 贺秋利, 张红晨, 宋鹏     
石家庄经济学院,石家庄 050031
摘要: 内蒙古西乌旗白音布拉格蛇绿岩带是新发现的内蒙古西乌旗迪彦庙蛇绿岩带的北带,主要由蛇纹石化方辉橄榄岩、层状-块状辉长岩、斜长岩、枕状玄武岩、角斑岩-石英角斑岩及硅质岩等构造单元组成。白音布拉格蛇绿岩中的熔岩按照地球化学特征可以分为三组:第1组属于玻安岩系,以富Si(SiO2=52.71%、61.22%)、Mg(MgO=6.81%和10.88%)和贫Ti(TiO2=0.49%、0.51%)、HREE及HFSE为特征;第2组具有低Ti(TiO2=0.62% ~ 0.78%)、高Mg(MgO =5.20%~11.30%) 的特征,LREE弱亏损、类似N-MORB的稀土配分模式,但相对N-MORB,又具有富集LILE,亏损Nb、Ta等高场强元素的特征,类似岛弧拉斑玄武岩(IAT);第3组表现为:岩石具有高Ti(TiO2=1.86%、1.91%)、高Mg(MgO=5.25% 和5.46%)及高P(P2O5=0.23%、0.27%),LREE和 HREE分异较为明显((La/Yb)N=2.32、 2.53)等特征,类似OIB。根据玻安岩与IAT的存在,推测白音布拉格蛇绿岩产于岛弧和弧前环境。
关键词: 蛇绿岩     地球化学     玻安岩     IAT     OIB     弧前环境     岛弧     内蒙古白音布拉格    
Geochemical characteristics of Baiyinbulage ophiolite in Xi U jimqin Banner, Inner Mongolia
LI YingJie, WANG JinFang, LI HongYang, DONG PeiPei, HE QiuLi, ZHANG HongChen, SONG Peng     
Shijiazhuang University of Economics, Shijiazhuang 050031, China
Abstract: Baiyinbulage ophiolite lies in the northern part of Diyanmiao ophiolite in Xi U jimqin Banner, Inner Mongolia. Baiyinbulage ophiolite is mainly composed of augite peridotite, beded-massive gabbro, anorthosite, pillow basalt, keratophyre, baschtauite, and chert. According to geochemical characteristics, the lavas of Baiyinbulage ophiolite are divided into three groups, the first group belong to boninite series, which are characteristic of enrichment in Si (SiO2=52.71%, 61.22%), Mg (MgO=6.81%, 10.88%) and depletion of Ti (TiO2=0.48%, 0.51%), HREE, HFSE; the second are similar to island arc tholeiite (IAT), with low Ti (TiO2=0.62%~0.78%), high Mg (MgO=5.20%~11.30%), and the chondrite-normalized REE patterns of the second group are of characteristics of LREE depletion, similar to N-MORB, while the spider diagram shows the enrichment of the LILEs and depletion of HFSEs, the unique feature of the arc volcanic rocks; the third are similar to the ocean island basalt (OIB), characterized by high Ti (TiO2=1.86%, 1.91%), Mg(MgO=5.25%, 5.46%) and P(P2O5=0.23%, 0.27%), and high Th/Ta radios (2.32, 2. 53). According to the existence of boninite and IAT, we suggest that the Baiyinbulage ophiolite was likely formed in the island arc and fore-arc setting.
Key words: Ophiolite     Geochemistry     Boninite     IAT     OIB     Fore-arc setting     Baiyinbulage, Inner Mongolia    

蛇绿岩是在板块汇聚作用中卷入造山带的古洋盆岩石圈残片, 对于重建古洋盆、研究大陆岩石圈构造和演化过程都具有重要意义(Coleman,1987Xu et al., 2002)。但是由于蛇绿岩形成于古老的年代,其形成与就位经历了与造山带演化相关的构造运动、岩浆活动、变质作用的改造,确定蛇绿岩的构造环境是不容易的,需要将蛇绿岩的野外特征、内部结构、地球化学性质及区域上的构造活动结合起来研究,因此也一直是地学界争论最激烈的论题之一(Pearce et al., 1984张旗和周国庆,2001周国庆,2008)。

兴蒙造山带位于中朝古板块与西伯利亚古板块之间,是在古生代经过俯冲-增生形成的复合造山带(Şengör et al., 1993Ruzhentsev and Mossakovskiy, 1996Buchan et al., 2002Xiao et al., 2002, 2003, 2004Xu et al., 2003b朱永峰和徐新,2006Windley et al., 2007徐新等,2007刘希军等,2009)。在兴蒙褶皱带,表现为由多条新元古代-早古生代的蛇绿混杂岩、岛弧或活动陆源岩浆-沉积增生楔组成,发育多条蛇绿岩带(张旗和周国庆,2001)(图 1)。已有资料显示,贺根山蛇绿岩的堆晶岩为PTG系列的,熔岩具MORB与IAT过度的特征(Robinson et al., 1999);温都尔庙熔岩具E-MORE和OIB与E-MORE之间(张旗和周国庆,2001黄金香等,2006);巴彦敖包-交其尔玄武岩具OIB和大洋岛弧玄武岩(黄金香等,2006);朝克山基性岩具岛弧火山岩的特征(王树庆等,2008);索伦山发育玻安岩。王焰等(2000) 发现兴蒙褶皱带存在埃达克岩,表明在早古生代晚期该区存在洋内消减事件。因此,温都尔庙、巴彦敖包-交其尔、朝克山及贺根山定为岛弧或弧后盆地较合适,索伦山形成于弧前环境,总体上内蒙古蛇绿岩应属于SSZ型(Robinson et al., 1999张旗和周国庆,2001许立权和邓晋福,2006Li,2006Miao et al., 2008)。

图 1 内蒙古西乌旗白音布拉格蛇绿岩区域构造简图 Fig. 1 Simplified regional tectonic map of Baiyinbulage ophiolite in Xi Ujimqin, Inner Mongolian

内蒙西乌旗迪彦庙蛇绿岩位于二连浩特-贺根山与交其尔-锡林浩特一线之间(图 1),是笔者在开展中国地质调查局下发的《内蒙古1︰5万迪彦庙、沙日勒昭、太本庙、多尔博勒金和热木幅区调》项目时新发现的(李英杰等,2012)。白音布拉格蛇绿岩带是内蒙古西乌旗迪彦庙蛇绿岩带的北带(图 2),目前对其还没有进行详细的地球化学研究,本文在前期研究基础上,通过对白音布拉格蛇绿岩的玄武岩进行较系统的地球化学研究,探讨其形成的构造环境,以期为兴蒙造山带在该地区的构造演化提供地球化学限定。

图 2 西乌旗迪彦庙蛇绿岩分布图 Fig. 2 Distribution of Diyanmiao ophiolite in Xi Ujimqin
1 地质概况

内蒙西乌旗迪彦庙蛇绿岩根据出露情况分为南北两个带:北部白音布拉格蛇绿岩带和南部孬来可吐蛇绿岩带(图 2)(李英杰等,2012)。白音布拉格蛇绿岩带出露于白音布拉格-陶勒斯陶勒盖-温多尔图一带,近EW向转NE向展布,带宽约3km,断续延伸约30km(图 2)。该带蛇绿岩的岩石出露较齐全,岩性主要为:蛇纹石化方辉橄榄岩、层状辉长岩、中粗粒-细粒均质块状辉长岩、斜长岩、枕状玄武岩、球颗玄武岩、角砾状玄武岩、角斑岩、石英角斑岩,其中以玄武岩最为发育,厚度最大,构成蛇绿岩的主体,局部玄武岩中夹有纹层状硅质岩、生物碎屑灰岩及硅质泥岩。白音布拉格蛇绿岩剖面的岩石组合层序较为完整(图 3),表现为底部为蛇纹石化方辉橄榄岩,向上依次为层状辉长岩、中粗粒-细粒均质块状辉长岩、斜长岩、玄武岩、枕状玄武岩和硅质岩,各单元断续呈背形分布。

图 3 白音布拉格蛇绿岩剖面图 1-蛇纹石化方辉橄榄岩;2-层状辉长岩;3-均质块状辉长岩;4-斜长岩;5-块状玄武岩;6-枕状玄武岩;7-硅质岩;8-生物碎屑灰岩;9-硅质泥岩;10-断层 Fig. 3 Profile of Baiyinbulage ophiolite

方辉橄榄岩(图 4a)位于蛇绿岩的底部,主要分布于白音布拉格东南部,出露面积较大,与上覆的辉长岩呈韧性剪切带接触,发育强烈片理化;呈黑绿色,他形粒状变晶结构,块状构造、片状构造。主要矿物组成:橄榄石:70%~80%,斜方辉石:20%~30%,少量铬铁矿、磁铁矿、透辉石。大多数方辉橄榄岩强烈蛇纹石化,橄榄石、辉石蚀变为蛇纹石,未蚀变的橄榄石显示折扭带状,颗粒边界模糊不清,可见波状消光、矿物的定向拉长、有时可见滑动双晶。

图 4 白音布拉格蛇绿岩野外和显微镜下照片 (a)-蛇纹石化方辉橄榄岩野外露头;(b)-蛇纹石化方辉橄榄岩显微镜下照片;(c)-辉长岩野外露头;(d)-辉长岩显微镜下照片;(e)-枕状玄武岩野外露头;(f)-枕状玄武岩显微镜下照片 Fig. 4 Field and microscopic features of the Baiyinbulage ophiolite

辉长岩单元在白音布拉格蛇绿岩带内断续出露,主要分布于白音布拉格东南部及北部,与蛇纹石化方辉橄榄岩和玄武岩呈韧性剪切带接触。该单元岩性从下向上依次为层状辉长岩、中粗粒-细粒均质块状辉长岩(图 4c),辉长岩的顶部出露斜长岩。辉长岩的矿物成分、结构、构造在垂向上呈现出明显的规律性变化:从下到上,矿物组成中暗色矿物-辉石的含量由多到少,由深色辉长岩到浅色辉长岩,至几乎全部由浅色矿物斜长石组成的斜长岩;在结晶程度上自下而上逐渐降低,由粗粒(局部伟晶结构)到中粗粒辉长岩,至细粒辉长岩;在构造上从下而上,由条带状、层状辉长岩,到均质块状辉长岩。辉长岩镜下(图 4d)呈中粗粒-中细粒结构、变余辉长结构、辉长-辉绿结构,主要矿物组成:斜长石:40%~45%,辉石:35%~40%,副矿物为磁铁矿和钛铁矿,含量约为5%。岩石蚀变较强,主要表现为斜长石的黝帘石化和辉石的纤闪石化。辉石几乎全为纤闪石化,部分被后期绿泥石交代而呈淡绿色调,纤闪石呈浅黄到黄绿色调,可见明显的闪石式解理,晶体大小一般约为0.20~0.30mm。磁铁矿和钛铁矿相互共生产出,在岩石中均匀分布,多为不规则状,少量呈交代假象。

火山熔岩单元为白音布拉格蛇绿岩的主要组成单元,出露规模最为广泛,约占蛇绿岩出露面积的70%。与辉长岩呈韧性剪切带接触,主要为块状玄武岩、枕状玄武岩(图 4e, f),局部发育球颗玄武岩、角砾状玄武岩,以及少量角斑岩、石英角斑岩等较酸的海底熔岩。玄武岩经历了低级变质作用,主要呈黑灰色、深绿色、青绿色,发育枕状构造、块状构造、杏仁状构造,杏仁体多为石英和绿帘石。具拉斑结构、间粒结构、间隐结构、斑状结构,斑晶主要为斜长石,其次为少量单斜辉石,基质为钠长石和单斜辉石组成的间粒结构。

白音布拉格蛇绿岩的上覆岩系主要为纹层状硅质岩和硅质泥岩。硅质岩呈青灰色、青绿色、淡红色、紫红色发育纹层状构造、薄层状构造,致密、坚硬、性脆,矿物成分为石英、玉髓、蛋白石及粘土矿物等,见少量圆形、椭圆形放射虫遗迹(被玉髓取代),有不均匀的重结晶现象,有些硅质岩不纯,和粘土矿物构成水平纹理构造。硅质泥岩呈灰黑色、黄褐色,薄板状构造,局部夹有灰岩透镜体。

白音布拉格蛇绿岩带内普遍发育构造糜棱岩带,糜棱岩化和片理化作用强烈而明显。在强变形带中蛇纹石化方辉橄榄岩形成蛇纹石片岩,细粒均质辉长岩形成糜棱岩化片理化细粒辉长岩,玄武岩形成绿片岩,石英角斑岩形成绢云石英片岩、眼球状糜棱岩,灰岩形成方解石片岩,硅质泥岩形成千枚岩。

2 地球化学特征 2.1 样品处理及分析方法

主量元素、微量元素分析测试由河北省区域地质矿产调查研究所实验室罗善霞分析。分析样品尽量采集野外新鲜岩石样品,室内先去除风化面,手工碎至1~5mm,去除杏仁体后轮流用稀硝酸与稀盐酸浸泡清洗,烘干后用不锈钢钵粉碎至200目用于化学分析。主量成分、Zr、Sr采用GB/T 14506.28-2010方法,Axios max X射线荧光光谱仪测定分析;稀土元素、微量元素采用GB/T 14506.30-2010方法,用X Serise2等离子体质谱仪测定分析。主量元素的分析精度好于5%,微量元素的分析精度优于10%,微量元素分析流程参阅刘颖等(1996) 。分析结果见表 1

表 1 白音布拉格蛇绿岩的岩性主化学组成(wt%)和微量元素丰度(×10-6) Table 1 Major (wt%), trace element (×10-6) analyzing results of Baiyinbulage ophiolite
2.2 蚀变的影响

在蛇绿岩各单元中,地幔橄榄岩Mg、Fe含量高,微量元素,尤其是HFSE和REE含量低,精确测定难度较大。辉长岩由于经历了不同程度的分离结晶作用,原始岩浆性质已难追踪。因此,蛇绿岩中的熔岩是最能体现其地球化学特征的岩石单元(张旗和周国庆,2001沈渭洲等,2003)。本文将重点讨论白音布拉格蛇绿岩熔岩的地球化学性质。然而,蛇绿岩中的熔岩一般经历了不同程度水热活动的蚀变作用(Hess,1965Alt and Teagle, 2000),以及洋内环境下的绿片岩至角闪岩相变质作用(Miyashiro, 1975)。研究表明,熔岩与海水发生低温反应时,Fe和Si 轻微淋滤而 Na和Mg 富集(Miyashiro, 1975),Ca 相对亏损,Al、Ti和P 最不活跃(Scott and Hajash, 1976; Seyfried et al., 1978)。微量元素(Y、Zr、Nb、V、Cr、Co、Ni)、REE、Th 及 Ta 相对稳定(Gillis and Thompson, 1993)。在水热蚀变中,Ba 显示可变的蚀变趋势(Humphris and Thompson, 1978),Pb中等至强烈亏损(Teagle and Alt, 2004),枕状熔岩玻璃外壳的蚀变橙玄玻璃化将导致K、Rb和Cs 的富集(Staudigel and Hart, 1983)。 因此,Al、P、Ti、Y、Zr、Nb、V、Cr、Co、Ni、Th 、Ta及REE是这些作用过程中相对稳定的元素 (Ludden and Thompson, 1978; Bienvenu et al., 1990; Xu et al., 2003a),而Ti、V、Th、Yb、Nb 在变质作用和蚀变中最不活跃,它们是探讨岩石成因和源区性质的示踪剂(Dilek and Furnes, 2011张进等,2012)。

2.3 主量元素地球化学

白音布拉格蛇绿岩的化学分析列于表 1,从表中看出, 白音布拉格蛇绿岩的玄武岩和玄武安山岩按TiO2含量的高低,结合微量元素和REE特征,可分为三组:第1组岩石富Si和Mg,贫Ti,与典型的玻安岩特征相似(Hickey and Frey, 1982)。其SiO2含量(SiO2=52.71%、61.22%)大体与玄武-安山岩和安山岩相当, 但MgO含量较高, 为6.81%和10.88%, 比安山岩MgO的平均含量(4.36%)(张旗和周国庆, 2001)高出许多,相应的其Mg#值(Mg/(Mg+∑Fe))为0.48和0.54,指示熔体具有原始岩浆的特征(Crawn et al., 1989)。TiO2含量的为0.49%和0.51%,略高于典型的玻安岩的TiO2含量(0.3%),与北祁连大岔大阪玻安岩相似(0.48%)(张旗等,1998);第2组岩石低Ti、高Mg和Al。岩石SiO2含量48.96%~52.89% (表 1),MgO含量为5.20%~11.30%,Mg#值为0.39~0.59,Al2O3含量14.61%~19.29%,TiO2含量为0.62%~0.78%,与岛弧拉斑玄武岩(IAT)(TiO2平均为0.8%;Sun, 1980)相似;第3组岩石高Ti、Mg、P。玄武岩 SiO2含量为46.21%和50.75%,Al2O3含量为16.46%和20.66%,MgO含量为5.25%和5.46%,TiO2含量为1.86%和1.91%,明显高于IAT(0.8%)及MORB(1%~1.5%),而与加拿大Flin Flon带Long Bay的OIB(洋岛玄武岩)(1.35%~2.29%; Stern et al., 1995)、克拉玛依OIB枕状玄武岩(1.29%~2.48%;朱永峰等,2007),及西准噶尔玛依勒OIB枕状玄武(1.65%~3.13%;杨学高等,2013)相近。P2O5含量为0.23%和0.27%,平均为0.25%,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,显示OIB(洋岛玄武岩)的特征。考虑到岩石样品有轻微的蚀变,利用抗蚀变元素图解Nb/Y-Zr/TiO2(图 5)对白音布拉格玄武岩投图,样品主要落于玄武/安山岩区。

图 5 白音布拉格蛇绿岩熔岩Nb/Y-Zr/TiO2图(底图据Winchester and Floyd, 1977) Fig. 5 Nb/Y-Zr/TiO2 diagram of lavas in Baiyinbulage ophiolite (base diagram after Winchester and Floyd, 1977)
2.4 微量元素地球化学

第1组岩石微量元素相关比值低,低HFSE和HREE。岩石的Ti/Zr值为59.06和59.61,与玻安岩的Ti/Zr比值(23~67)相似。Y含量为球粒陨石的4.7倍和6.1倍, Yb含量为球粒陨石的4.5倍和6.6倍,与典型玻安岩相当(Y不到5倍, Yb则小于球粒陨石的7倍),而MORB平均的Y和Yb则分别是球粒陨石的14和15倍(Hickey and Frey, 1982; Sun and McDonough, 1989)。在正常大洋中脊玄武岩(N-MORB)标准化微量元素蛛网图中(图 6a), 第1组岩石亏损高场强元素HFSE,富集LILE,Ti和Nb相对亏损;第2组岩石LREE弱亏损,低HFSE和HREE,但较第1组岩石HFSE和HREE稍高。Yb为球粒陨石的6.05~8.42倍,与IAT的HREE(Yb通常不到球粒陨石的10倍;据Sun,1980)相似, 显示其并不是来自一个开阔大洋MORB的环境(HREE>球粒陨石的10倍)(Sun, 1980; Pearce et al., 1984; Wilson, 1989)。Zr/ Y值为1.64~2.91。 在REE球粒陨石标准化配分图解中(图 6c),显示 LREE弱亏损或平坦,和洋中脊玄武岩(MORB)、弧后盆地玄武岩相似,指示岩浆源于强烈亏损的地幔源区,表明它们的源区有一个亏损地幔组分的卷人(许继峰等,2001; Xu et al., 2003b)。在正常大洋中脊玄武岩(N-MORB)标准化微量元素蛛网图(图 6a)上,表现为LILE的相对富集,亏损HFSE (Nb、Ta),有Nb、Ta的负异常。第3组岩石稀土元素总量较高(∑REE=76.98×10-6、112.2×10-6),明显高于MORB (39.1×10-6),轻重稀土分异较明显((La/Yb) N=2.32、2.53),无明显Eu异常(δEu=0.95、1.16)。 在球粒陨石标准化曲线图上(图 6c), 轻稀土相对富集,重稀土相对亏损,略呈右倾型。这种稀土配分模式与典型洋岛玄武岩(OIB) (Sun and McDonugh, 1989)、夏威夷(Xia et al., 2008)及日喀则(Hofmann and Jochum, 1996)海山玄武岩相似。在N-MORB标准化的微量元素蛛网图(图 6b)中,样品的微量元素含量均远远大于N-MORB。第3组岩石的大离子亲石元素(LILE) Rb、Ba 、Th相对富集,K、Sr相对亏损,高场强元素(HFSE)Zr、Hf、Nb相对亏损,Zr/Hf比值为25.5、28.9,低于OIB(35.9),但远高于大陆地壳值(Zr/Hf=11)。总体上,本组玄武岩样品的曲线与OIB形态基本一致。

图 6 白音布拉格蛇绿岩熔岩稀土元素球粒陨石标准化图(标准化值据Taylor and Mcleman, 1985)、原始地幔标准化蛛网图(标准化值据Sun and McDonough, 1989)及Th/Yb-Ta/Yb图解(据 Pearce, 1982) Fig. 6 Chondite-normalized REE pattern (normalization values after Taylor and Mcleman, 1985), distribution patterns of trace elements (normalization values after Sun and McDonough, 1989) and Th/Yb-Ta/Yb diagram (after Pearce, 1982) of the lavas from the Baiyinbulage ophiolite
3 构造环境讨论

蛇绿岩的形成环境具有多样性,越来越多的研究表明大陆造山带中大多数蛇绿岩不是在大洋中脊中生成的,而是形成于俯冲带上(Supra-Subduction Zone,简称SSZ)的构造环境,例如:弧前盆地、弧后盆地、岛弧、大陆被动陆缘或小洋盆等(Bloomer et al. 1989Pearce et al., 1984; Stern et al., 1989;张旗和周国庆,2001)。已有资料显示内蒙古蛇绿岩属于SSZ型,本文较系统地分析了新发现的白音布拉格蛇绿岩熔岩的地球化学特征,以期为该地区的构造演化提供地球化学依据。

白音布拉格蛇绿岩熔岩发育三种地球化学类型。第1组属于玻安岩系,岩石富Si、贫Ti、高Mg#、亏损HFSE、HREE,富集LILE和H2O。玻安岩贫Ti是其源区Ti强烈亏损造成的,表明地幔源区已经经历了不止一次的部分熔融事件(Sun and Nesbitt, 1978)。 正是其极低的TiO2含量,导致了白音布拉格玻安岩系低的Ti/Zr比值(59.06和59.61), 玻安岩的Ti/Zr比值在23~67之间, 而MORB和岛弧拉斑玄武岩的Ti/Zr比值均接近110 (Sun and Nesbitt, 1978)。此外, 白音布拉格玻安岩的Mg#较高(0.48和0.54), 表明白音布拉格玻安岩有原始岩浆特征。在微量元素蛛网图上, 白音布拉格玻安岩具Nb和Ta负异常(图 6a), 在Th/Yb-Ta/Yb图(图 6d)、Hf/3-Th-Ta图(图 7a)及2Nb-Zr/4-Y图(图 7b)上均落在岛弧火山岩区域,表明它们处于消减带之上的环境。综上所述,白音布拉格玻安岩的地球化学特征与西太平洋岛弧弧前区的玻安岩类似,目前研究显示,西太平洋的第三纪玻安岩(伊豆-小笠原、马里亚那、巴布亚新几内亚、新喀里多尼亚等)均产于弧前环境(Meijer, 1980; Hickey and Frey, 1982; Bloomer and Hawkins, 1983; Falloon and Crawford, 1991; Ishii et al., 1992Sobolev and Danyshevsky, 1994)。同时,大量蛇绿岩研究和深海钻探揭示,造山带蛇绿岩主要是弧前和岛弧扩张作用的产物(Bloomer and Hawkins, 1983; Bédard et al., 1998)。因此,蛇绿岩应该主要形成在弧前盆地环境,而非成熟的洋脊和弧后盆地环境(Bloomer and Hawkins, 1983),这也很好地解释了为什么蛇绿岩中经常见到玻安岩的问题(Bédard et al., 1998)。

图 7 白音布拉格蛇绿岩熔岩构造环境判别图 (a)-Hf/3-Th-Ta图解(据Wood,1980): N-MORB正常洋中脊玄武岩,E-MORB富集洋中脊玄武岩,CAB-钙碱性玄武岩,WPA-板内碱性玄武岩,IAT-岛弧拉斑玄武岩; (b)-2Nb-Zr/4-Y图解(据Meschede, 1986)):A-N-MORB ; B-E-MORB和板内拉斑玄武岩; C-板内碱性玄武岩; D-火山弧玄武岩 Fig. 7 Trace element composition for the tectonic setting discrimination for the lavas of the Baiyinbulage ophiolite (after Wood, 1980; Meschede, 1986)

但是,与典型玻安岩相比,白音布拉格玻安岩具典型玻安岩与IAT过度的特征,Ti、Mg#、HFSE、HREE稍高,可能为玻安岩岩浆与IAT岩浆发生混合作用的结果。

第2组岩石属岛弧拉斑玄武岩(IAT),TiO2含量较低(0.62%~0.78%),明显低于洋脊玄武岩TiO2的平均值1.5% (Pearce, 1983);P2O5含量为0. 03%~0. 07%,与洋中脊玄武岩的P2O5的平均含量0. 14%相差甚远,以上特征显示第2组玄武岩不具有大洋中脊玄武岩和洋岛玄武岩的特点。N-MORB标准化的微量元素蛛网图(图 6a)显示,第2组玄武岩的配分曲线总体为近平坦型分布型式,尤其是曲线的后半部Nd-Lu段,但是,样品以富集Sr、Rb等大离子亲石元素,亏损Nb、Ta等高场强元素为特点,在蛛网图中具有明显的Sr、Rb的隆起和Nb、Ta低谷,尤其是Nb的负异常,具有岛弧玄武岩的特征。在岛弧区,由于普遍发生洋壳和沉积物向岩石圈深部的再循环,在那样的物理化学条件下,或者由于高场强元素倾向于残留在难熔矿物相(例如金红石、榍石)中,或者在流体与上覆地幔楔相互作用过程中高场强元素具有较其它不相容元素高的晶/液分配系数,从而造成高场强元素的亏损(Pearce and Deng, 1988; Gribble et al., 1998张旗和周国庆,2001赖绍聪和刘池阳,2003; 王保弟等,2007)。另一方面,从第2组玄武岩的稀土配分模式上看,主要显示不同程度的LREE亏损,这一特征又相似于典型的洋中脊玄武岩,说明它们兼具岛弧玄武岩和洋中脊玄武岩的成分特征,指示它们的地幔源区可能同时卷入了两个组分。在Th/Yb-Ta/Yb图(图 6d)和Hf/3-Th-Ta图(图 7a)上,均落在IAT区域, 在2Nb-Zr/4-Y图(图 7b)上落在岛弧火山岩区域,综上所述,表明第2组岩石与IAT相似,有可能形成于岛弧及相关环境。

第3组岩石具有高Ti(TiO2含量为1.86%和1.91%)、高Mg(MgO含量为5.25%和5.46%)及高P(P2O5含量为0.23%和0.27%)的特征,LREE和HREE分异较为明显((La/Yb)N=2.32、2. 53)等特征,这些特征与OIB类似(张旗和周国庆,2001)。同时,第3组岩石REE球粒陨石模式图(图 6c)和微量元素蛛网图(图 6b)均显示OIB的特征,同时,也和克拉玛依OIB型枕状玄武岩(朱永峰等,2007)、阿尼玛卿蛇绿岩(郭安林等,2006)、及西准噶尔玛依勒蛇绿混杂岩(杨高学等,2013)中OIB相近。在Hf/3-Th-Ta图(图 7a)上,样品落入板内玄武岩和火山弧玄武岩区域。由此可见,第3组玄武岩可能形成于大洋板内的洋岛或海山环境,不应该属于蛇绿岩的组成单元,而是大洋环境中岛弧岩浆喷发的产物。根据野外调查,这些OIB型玄武岩与生物碎屑灰岩、硅质岩、硅泥质岩共生,表明其形成于大洋环境。局部见玄武岩之上覆盖角斑岩和石英角斑岩,表现出岩浆由基性到中酸性的演化特征。

根据前人研究,蛇绿岩的形成环境复杂,因此蛇绿岩的玄武岩地球化学性质变化大,在一个蛇绿岩中往往有不同类型地球化学性质的玄武岩产出(张旗和周国庆,2001李文霞等,2012)。关于蛇绿岩的地球化学类型是一个十分复杂且存在争议的问题,在俯冲带之上的岛弧和弧前环境形成的是岛弧拉斑玄武岩(IAT)和玻安岩,不成熟的弧后盆地玄武岩兼有IAT和MORB的特征(Weaver et al., 1979 ; Hawkins, 2003),成熟的弧后盆地玄武岩为MORB型,弧间盆地环境产出的岛弧蛇绿岩也具有IAT和MORB的性质(张旗等,1999)。 根据目前研究,白音布拉格蛇绿岩中发育三种类型熔岩:玻安岩、IAT及OIB。玻安岩和IAT为岛弧蛇绿岩残片,而OIB是大洋环境中岛弧岩浆喷发的产物。白音布拉格玻安岩具有玻安岩和IAT过度的特征,结合野外观察,玻安岩上覆于具IAT特征的枕状熔岩之上,指示在岛弧洋壳形成之后,可能又出现了新的消减事件,并在消减带之前的弧前环境生成了玻安岩,覆盖在早形成的岛弧洋壳之上。综上所述,推测白音布拉格蛇绿岩形成于岛弧和弧前环境的可能性比较大。

4 结论

(1) 白音布拉格蛇绿岩的熔岩主要显示三种类型:第1组岩石为玻安岩系;第2组岩石具IAT的特征;第3组岩石与OIB相似。

(2) 白音布拉格蛇绿岩的玻安岩具典型玻安岩与IAT过度的特征,野外观察见玻安岩上覆于具IAT特征的玄武岩之上,指示在岛弧洋壳形成之后叠加了弧前环境的岩浆活动,显示在白音布拉格洋盆中可能出现了一个新的洋内消减事件。因此,白音布拉格蛇绿岩形成于岛弧-弧前盆地环境的可能性比较大。

致谢 本文在野外调查和写作过程中得到中国地质调查局天津地质调查中心刘永顺、河北省地质调查院宋立军等的热情指导和帮助;石家庄经济学院张宗超、郭垚嘉、王立考、武鹏、杨飞等也做了大量工作;两位审稿专家提出了宝贵的修改意见;在此一并表示衷心的感谢!
参考文献
[] Alt JC, Teagle DAH. 2000. Hydrothermal alteration and fluid fluxes in ophiolites and oceanic crust. In: Dilek Y, Moores EM, Elthon D et al. (eds.). Ophiolites and Oceanic Crust: New Insights from Field Studies and the Ocean Drilling Program. Geological Society of America Special Paper, 349: 273–282. DOI:10.1130/0-8137-2349-3
[] Bédard JH, Lauzière K, Tremblay A, Sangster A. 1998. Evidence for forearc seafloor-spreading from the Betts Cove ophiolite, Newfoundland: Oceanic crust of boninitic affinity. Tectonophysics, 284(3-4): 233–245. DOI:10.1016/S0040-1951(97)00182-0
[] Bienvenu P, Bougault H, Joron JL, Treuil M, Dmitriev L. 1990. MORB alteration: Rare-earth element/non-rare-earth hygromagmaphile element fractionation. Chemical Geology, 82: 1–14. DOI:10.1016/0009-2541(90)90070-N
[] Bloomer SH and Hawkins JW. 1983. Gabbroic and ultramafic rocks from the Mariana Trench: An island arc ophiolite. In: Hayes DE (ed.). The Tectonic and Geologic Evolution of southern Asian Seas and Islands, Part 2. Am. Geophy. Union, Washington D.C., 294-317
[] Bloomer SH, Stern RJ, Smoot NC. 1989. Physical volcanology of the submarine Mariana and Volcano Arcs. Bulletin of Volcanology, 51(3): 210–224. DOI:10.1007/BF01067957
[] Buchan C, Pfänder J, Kröner A, Brewer TS, Tomurtogoo O, Tomurhuu D, Cunningham D, Windley BF. 2002. Timing of accretion and collisional deformation in the Central Asian Orogenic Belt: Implications of granite geochronology in the Bayankhongor Ophiolite Zone. Chemical Geology, 192(1-2): 23–45. DOI:10.1016/S0009-2541(02)00138-9
[] Coleman RG. 1977. Ophiolites: Ancient Oceanic Lithosphere. Berlin: Springer-Verlag: 78-123.
[] Crawn AJ, Falloon TJ, Green DH. 1989. Classification, petrogenesis and tectonic settings of boninites. In: Crawford AJ (ed.). Boninites.. London: Unwin Hyman: 149.
[] Dilek Y, Furnes H. 2011. Ophiolite genesis and global tectonics: Geochemical and tectonic fingerprinting of ancient oceanic lithosphere. Geological Society of America Bulletin, 123(3-4): 387–411. DOI:10.1130/B30446.1
[] Falloon TJ, Crawford AJ. 1991. The petrogenesis of high-calcium boninite lavas dredged from the northern Tonga ridge. Earth and Planetary Science Letters, 102(3-4): 375–394. DOI:10.1016/0012-821X(91)90030-L
[] Gillis KM, Thompson G. 1993. Metabasalts from the Mid-Atlantic Ridge: New insights into hydrothermal systems in slow-spreading crust. Contributions to Mineralogy and Petrology, 113(4): 502–523. DOI:10.1007/BF00698319
[] Gribble RF, Stern RJ, Newman S, Bloomer SH, O'Hearn T. 1998. Chemical and isotopic composition of lavas from the northern Mariana Trough: Implications for magmagenesis in back-arc basins. Journal of Petrology, 39(1): 125–154. DOI:10.1093/petroj/39.1.125
[] Guo AL, Zhang GW, Sun YG, Zheng JK, Liu Y, Wang JQ. 2006. Geochemistry and apatial distribution of OIB and MORB in Anymaqen ophiolite zone: Evidence of Majixueshan ancient ridge-centered hotspot. Science in China (Series D), 36(7): 618–629.
[] Hawkins JW. 2003. Geology of supra-subduction zones: Implications for the origin of ophiolites. Special Paper-Geological Society of America, 373: 227–268.
[] Hess HH. 1965. Mid-ocean ridges and tectonics of the sea floor, submarine geology and geophysics. In: Whittard WF and Bradshaw R (eds.). Proceedings of the 17th Symposium of the Colston Research Society. London: Butterworths, 317-334
[] Hickey RL, Frey FA. 1982. Geochemical characteristics of boninite series volcanics: Implications for their source. Geochimica et Cosmochimica Acta, 46(11): 2099–2115. DOI:10.1016/0016-7037(82)90188-0
[] 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
[] Huang JX, Zhao ZD, Zhang HF, Hou QY, Chen YL, Zhang BR, DePaolo DJ. 2006. Elemental and Sr-Nd-Pb isotopic geochemistry of the Wenduermiao and Bayanaobao-Jiaoqier ophiolites, Inner Mongolia: Constraints for the characteristics of the mantle domain of eastern Paleo-Asian Ocean. Acta Petrologica Sinica, 22(12): 2889–2900.
[] Humphris SE, Thompson G. 1978. Trace element mobility during hydrothermal alteration of oceanic basalts. Geochimica et Cosmochimica Acta, 42(1): 127–136.
[] Ishii T, Robinson PT, Maekawa H et al. 1992. Proto-ophiolite: Peridotites from diapiric serpentinite seamounts in the Izu-Oga-sawara-Mariana forearc, ODP Leg 125. 29th Inter. Geol. Cong. Abstract, 1, Kyoto Japan, 134
[] Lai SC, Liu CY. 2003. Geochemistry and genesis of the island-arc ophiolite in Anduo area, Tibetan Plateau. Acta Petrologica Sinica, 19(4): 675–682.
[] Li JY. 2006. Permian geodynamic setting of Northeast China and adjacent regions: Closure of the Paleo-Asian Ocean and subduction of the Paleo-Pacific Plate. Journal of Asian Earth Sciences, 26(3-4): 207–224. DOI:10.1016/j.jseaes.2005.09.001
[] Li YJ, Wang JF, Li HY, Liu YC, Dong PP, Liu DW, Bai H. 2012. Recognition of Diyanmiao ophiolite in Xi U jimqin Banner, Inner Mongolia. Acta Petrologica Sinica, 28(4): 1282–1290.
[] Li WX, Zhao ZD, Zhu DC, Dong GC, Zhou S, Mo XX, DePaolo D, Dilek Y. 2012. Geochemical discrimination of tectonic environments of the Yalung Zangpo ophiolite in southern Tibet. Acta Petrologica Sinica, 28(5): 1663–1673.
[] 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.
[] Liu Y, Liu HC, Li XH. 1996. Simultaneous and precise determination of 40 trace elements in rock samples using ICP-MS. Geochimica, 5(6): 552–558.
[] Ludden JN, Thompson G. 1978. Behaviour of rare earth elements during submarine weathering of tholeiitic basalt. Nature, 274(5667): 147–149. DOI:10.1038/274147a0
[] Meijer A. 1980. Primitive arc volcanism and a boninite series: Examples from western Pacific island arcs. In: Hayes DE (ed.). The Tectonic and Geologic Evolution of Southeast Asian Seas and Islands. Am. Geophys. Union, Washington, D.C., 269-282
[] Meschede M. 1986. A method of discriminating between different types of mid-ocean ridge basalts and continental tholeiites with the Nb-Zr-Y diagram. Chemical Geology, 56(3-4): 207–218. DOI:10.1016/0009-2541(86)90004-5
[] Miao LC, Fan WM, Liu DY, Zhang FQ, Shi YR, Guo F. 2008. Geochronology and geochemistry of the Hegenshan ophiolitic complex: Implications for late-stage tectonic evolution of the Inner Mongolia-Daxinganling Orogenic Belt, China. Journal of Asian Earth Sciences, 32(5-6): 348–370. DOI:10.1016/j.jseaes.2007.11.005
[] Miyashiro A. 1975. Classification, characteristics, and origin of ophiolites. Journal of Geology, 83(2): 249–281. DOI:10.1086/628085
[] Pearce JA. 1982. Trace element distribution diagrams for the tectonic interpretation of granitic rocks. Journal of Petroleum, 25(4): 956–983.
[] Pearce JA. 1983. The role of sub-continental lithosphere in magma genesis at destructive plate margins. In: Hawkesworth et al (eds.). Continental Basalts and Mantle Xenoliths. Nantwich Shiva, 230-249
[] 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 of London Special Publication, 16: 77–94. DOI:10.1144/GSL.SP.1984.016.01.06
[] Pearce JA, Deng WM. 1988. The ophiolites of the Tibetan Geotraverses, Lhasa to Golmud (1985) and Lhasa to Kathmandu (1986). In: Chang C et al. (eds.). The Geological Evolution of the Tibet. London: The Royal Society, 327(1594): 215–238.
[] Robinson PT, Zhou MF, Hu XF, Reynolds P, Rai WJ, Yang JS. 1999. Geochemical constraints on the origin of the Hegenshan ophiolite, Inner Mongolia, China. Journal of Asian Earth Sciences, 17(4): 423–442. DOI:10.1016/S1367-9120(99)00016-4
[] Ruzhentsev SV, Mossakovskiy AA. 1996. Geodynamics and tectonic evolution of the Central Asian Paleozoic structures as the result of the interaction between the Pacific and Indo-Atlantic segments of the Earth. Geotectonics, 29(4): 294–311.
[] Scott RB, Hajash A Jr. 1976. Initial submarine alteration of basaltic pillow lavas: A microprobe study. American Journal of Science, 276(4): 480–501. DOI:10.2475/ajs.276.4.480
[] ŞengörAMC, Natal’inBA, RurtmanVS. 1993. Evolution of the Altaid tectonic collage and Palaeozoic crustal growth in Eurasia. Nature, 364(6435): 299–307.
[] Seyfried WE, Mottl M, Bischoff JL. 1978. Seawater/basalt ratio effects on the chemistry and mineralogy of spilites from the ocean floor. Nature, 275(5677): 211–213. DOI:10.1038/275211a0
[] Shen WZ, Gao JF, Xu SJ, et al. 2003. Geochemical characteristics of the Shimian ophiolite, Sichuan Province and its tectonic significance. Geological Review, 49(1): 17–27.
[] Sobolev AV, Danyshevsky LV. 1994. Petrology and geochemistry of boninites from the north termination of the Tonga trench: Constraints on the generation conditions of primary high-Ca boninite magmas. J. Petrol., 35(5): 1183–1211. DOI:10.1093/petrology/35.5.1183
[] Staudigel H, Hart SR. 1983. Alteration of basaltic glass: Mechanisms and significance for the oceanic crust-seawater budget. Geochimica et Cosmochimica Acta, 47(3): 337–350. DOI:10.1016/0016-7037(83)90257-0
[] 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
[] Sun SS, Nesbitt RW. 1978. Geochemical regularities and genetic significance of ophiolitic basalts. Geology, 6(11): 689–693. DOI:10.1130/0091-7613(1978)6<689:GRAGSO>2.0.CO;2
[] Sun SS. 1980. Lead isotopic study of young volcanic rocks from mid-ocean ridges, ocean islands and island arcs. Phil. Trans. Roy. Soc, A297(1431): 409–445.
[] 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. Geological Society, London, Special Publication, 42(1): 313–345. DOI:10.1144/GSL.SP.1989.042.01.19
[] Taylor SR, Mcleman SM. 1985. The Continental Crust: Its Composition and Evolution. Oxford: Blackwell Scientific: 1-312.
[] Teagle DAH, Alt JC. 2004. Hydrothermal alteration of basalts beneath the Bent Hill massive sulfide deposit, Middle Valley, Juan de Fuca Ridge. Economic Geology, 99(3): 561–584. DOI:10.2113/gsecongeo.99.3.561
[] Wang BD, Xu JF, Zeng QG, et al. 2007. Geochemistry and genesis of Lhaguo Tso ophiolite in south of Gerze area, Center Tibet. Acta Petrologica Sinica, 23(6): 1521–1530.
[] Wang SQ, Xu JF, Liu XJ, et al. 2008. Geochemistry of the Chaokeshan ophiolite: Product of intra-oceanic back-arc basin. Acta Petrologica Sinica, 24(12): 2869–2879.
[] Wang Y, Zhang Q, Qian Q. 2000. Adakite: Geochemical characteristics and tectonic significances. Scientia Geologica Sinica, 35(2): 251–256.
[] Weaver SD, Saunder AD, Pankhurst RJ, Tarney J. 1979. A geochemical study of magmatism associated with the initial stages of back-arc spreading. Contributions to Mineralogy and Petrology, 68(2): 151–169. DOI:10.1007/BF00371897
[] Wilson M. 1989. Igneous Petrogenesis. London: Unwin Hyman.
[] 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
[] Xiao WJ, Windley BF, Hao J, et al. 2002. Arc-ophiolite obduction in the Western Kunlun Range (China): Implications for the Palaeozoic evolution of Central Asia. Journal of the Geological Society, 159(5): 517–528. DOI:10.1144/0016-764901-135
[] Xiao WJ, Windley BF, Hao J, Zhai MG. 2003. Accretion leading to collision and the Permian Solonker Suture, Inner Mongolia, China: Termination of the Central Asian orogenic belt. Tectonics, 22(6): 1–21.
[] Xiao WJ, Zhang LC, Qin KZ, et al. 2004. Paleozoic accretionary and collisional tectonics of the Eastern Tianshan (China): Implications for the continental growth of Central Asia. American Journal of Science, 304(4): 370–395.
[] Xu JF, Chen FR, Yu XY, Niu HC, Zheng ZP. 2001. Kuerti ophiolite in Altay area of North Xinjiang: Magmatism of an ancient back arc basin. Acta Petrologica et Mineralogica, 20(3): 344–352.
[] Xu JF, Castillo PR, Li XH, Yu XY, Zhang BR, Han YW. 2002. MORB-type rocks from the Paleo-Tethyan Mian-Lueyang northern ophiolite in the Qinling Mountains, central China: Implications for the source of the low 206Pb/204Pb and high 143Nd/144Nd mantle component in the Indian Ocean. Earth and Planetary Science Letters, 198(3-4): 323–337. DOI:10.1016/S0012-821X(02)00536-8
[] Xu JF, Castillo PR, Chen FR, Niu HC, Yu XY, Zhen ZP. 2003a. Geochemistry of Late Paleozoic mafic igneous rocks from the Kuerti area, Xinjiang, Northwest China: Implications for back-arc mantle evolution. Chemical Geology, 193(1-2): 137–154. DOI:10.1016/S0009-2541(02)00265-6
[] Xu JF, Castillo PR, Chen FR, et al. 2003b. Geochemistry of Late Paleozoic mafic igneous rocks from the Kuerti area, Xinjiang, Northwest China: Implications for back-arc mantle evolution. Chemical Geology, 193(1-2): 137–154. DOI:10.1016/S0009-2541(02)00265-6
[] Xu LQ, Deng JF. 2006. Tectonic environment of ophiolites in the Har Tolgoi area, Damao Qi, Inner Mongolia. Geology in China, 33(5): 1038–1043.
[] Xu X, Zhu YF, Chen B. 2007. Petrology of the Kamste ophiolite melange from East Junggar, Xinjiang, NW China. Acta Petrologica Sinica, 23(7): 1603–1610.
[] Yang GX, Li YJ, Yang BK, Liu ZW, Tong LL, Zhang HW. 2013. Zircon U-Pb geochronology and geochemistry of the Mayile ophiolitic melange in West Junggar and implications for source nature. Acta Petrologica Sinica, 29(1): 303–316.
[] Zhang J, Deng JF, Xiao QH, et al. 2012. New advances in the study of ophiolites. Geological Bulletin of China, 31(1): 1–12.
[] Zhang Q, Chen Y, Zhou DJ, et al. 1998. Geochemistry and genesis of Dachadaban ophiolite, North Qilian. Science in China (Series D), 28(1): 30–34.
[] Zhang Q, Qian Q, Wang Y. 1999. Geochemical study on igneous rocks of orogenic belts. Earth Science Frontiers, 6(3): 113–120.
[] Zhang Q, Zhou GQ. 2001. Ophiolite of China. Beijing: Science Press: 1-182.
[] Zhou GQ. 2008. Ophiolite: Some key aspects regarding its definition and classification. Journal of Nanjing University (Natural Sciences), 44(1): 1–24.
[] Zhu YF, Xu X. 2006. The discovery of Early Ordovician ophiolite melange in Taerbahatai Mts., Xinjiang, NW China. Acta Petrologica Sinica, 22(12): 2833–2842.
[] Zhu YF, Xu X, Wei SH, 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.
[] 郭安林, 张国伟, 孙延贵, 郑健康, 刘哗, 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.
[] 黄金香, 赵志丹, 张宏飞, 等. 2006. 内蒙古温都尔庙和巴彦敖包-交其尔蛇绿岩的元素与同位素地球化学: 对古亚洲洋东部地幔域特征的限制. 岩石学报, 22(12): 2889–2900.
[] 赖绍聪, 刘池阳. 2003. 青藏高原安多岛弧型蛇绿岩地球化学及成因. 岩石学报, 19(4): 675–682.
[] 李英杰, 王金芳, 李红阳, 等. 2012. 内蒙古西乌珠穆沁旗迪彦庙蛇绿岩的识别. 岩石学报, 28(4): 1282–1290.
[] 李文霞, 赵志丹, 朱弟成, 等. 2012. 西藏雅鲁藏布蛇绿岩形成构造环境的地球化学鉴别. 岩石学报, 28(5): 1663–1673.
[] 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.
[] 刘颖, 刘海臣, 李献华. 1996. 用ICP-MS准确测定岩石样品中的40余种微量元素. 地球化学, 5(6): 552–558.
[] 沈渭洲, 高剑峰, 徐士进, 等. 2003. 四川石棉蛇绿岩的地球化学特征及其构造意义. 地质论评, 49(1): 17–27.
[] 王保弟, 许继峰, 曾庆高, 等. 2007. 西藏改则地区拉果错蛇绿岩地球化学特征及成因. 岩石学报, 23(6): 1521–1530.
[] 王树庆, 许继峰, 刘希军, 等. 2008. 内蒙朝克山蛇绿岩地球化学: 洋内弧后盆地的产物. 岩石学报, 24(12): 2869–2879.
[] 王焰, 张旗, 钱青. 2000. 埃达克岩(adakite)的地球化学特征及其构造意义. 地质科学, 35(2): 251–256.
[] 许继峰, 陈繁荣, 于学元, 等. 2001. 新疆北部阿尔泰地区库尔提蛇绿岩: 古弧后盆地系统的产物. 岩石矿物学杂志, 20(3): 344–352.
[] 许立权, 邓晋福. 2006. 内蒙古达茂旗哈尔陶勒盖地区蛇绿岩形成环境探讨. 中国地质, 33(5): 1038–1043.
[] 徐新, 朱水峰, 陈博. 2007. 卡姆斯特蛇绿混杂岩的岩石学研究及其地质意义. 岩石学报, 23(7): 1603–1610.
[] 杨高学, 李永军, 杨宝凯, 等. 2013. 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. 岩石学报, 29(1): 303–316.
[] 张进, 邓晋福, 肖庆辉, 等. 2012. 蛇绿岩研究的最新进展. 地质通报, 31(1): 1–12.
[] 张旗, ChenY, 周德进, 等. 1998. 北祁连大岔大坂蛇绿岩的地球化学特征及其成因. 中国科学(D辑), 28(1): 30–34.
[] 张旗, 钱青, 王焰. 1999. 造山带火成岩地球化学研究. 地学前缘, 6(3): 113–120.
[] 张旗, 周国庆. 2001. 中国蛇绿岩. 北京: 科学出版社: 1-182.
[] 周国庆. 2008. 蛇绿岩研究新进展及其定义和分类的再讨论. 南京大学学报(自然科学版), 44(1): 1–24.
[] 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, 魏少妮, 宋彪, 郭漩. 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.