岩石学报  2016, Vol. 32 Issue (2): 289-302   PDF    
长江中下游地区繁昌盆地火山岩成因:锆石Hf-O同位素制约
刘建敏1, 闫峻1 , 陈丹丹2, 李全忠1, 刘晓强1, 姚洪忠1, 史磊1, 陈志洪2    
1. 合肥工业大学资源与环境工程学院, 合肥 230009;
2. 中国地质调查局南京地质矿产研究所, 南京 210016
摘要: 繁昌盆地是长江中下游地区沿江火山盆地之一,目前针对该盆地火山岩的研究相对薄弱,因此本文选择该盆地中分村组流纹岩、赤沙组粗安岩、蝌蚪山组流纹岩为研究对象,结合本课题组前期发表的研究成果,开展锆石原位Hf-O同位素和U-Pb年代学研究,以期深入探讨繁昌盆地火山岩的岩石成因。中分村组流纹岩、赤沙组粗安岩、蝌蚪山组流纹岩的LA-ICPMS锆石U-Pb定年结果分别为132.1±1.5Ma、129.1±1.8Ma和129.5±3.3Ma。三组火山岩的εHf(t)值分别为-8.2~-5.8、-6.0~-3.4、-7.4~-2.2,δ18O值分别为6.3‰~7.9‰、7.0‰~7.8‰、6.6‰~8.2‰,从中分村组到赤沙组再到蝌蚪山组εHf(t)、δ18O值逐渐升高。综合分析表明:中分村组、赤沙组、蝌蚪山组火山岩的源区相似,它们是新元古新生地壳熔融形成的岩浆和少量的富集岩石圈地幔部分熔融形成的岩浆混合后经结晶分异形成。从148~133Ma至132~126Ma,本地区经历了俯冲带构造环境至拉张环境的转换,古太平洋板片的俯冲及后撤的转换时间在132Ma左右。
关键词: 火山岩     锆石     Hf-O同位素     中生代     繁昌盆地     长江中下游    
Petrogenesis of the volcanic rocks in Fanchang basin, the Middle-Lower Yangtze River Belt: Zircon Hf-O isotopic constraints
LIU JianMin1, YAN Jun1 , CHEN DanDan2, LI QuanZhong1, LIU XiaoQiang1, YAO HongZhong1, SHI Lei1, CHEN ZhiHong2    
1. School of Resource and Environmental Engineering, Hefei University of Technology, Hefei 230009, China;
2. Nanjing Institute of Geology and Mineral Resources, China Geological Survey, Nanjing 210016, China
Abstract: Fanchang basin is one of the volcanic basins in the Middle-Lower Yangtze River Belt. Studies on the volcanic rocks in the basin are still weak, so this article carried out zircon Hf-O isotopes and U-Pb ages analysis on rhyolite from Zhongfencun Formation, trachyandesite from Chisha Formation and rhyolite from Kedoushan Formation in order to discuss petrogenesis of the volcanic rocks in Fanchang basin. The results of zircon LA-ICPMS U-Pb dating are 132.1±1.5Ma(Zhongfencun Formation), 129.1±1.8Ma(Chisha Formation) and 129.5±3.3Ma(Kedoushan Formation). The rang of zircon εHf(t) values are-8.2~-5.8,-6.0~-3.4,-7.4~-2.2 and the rang of zircon δ18O values are 6.3‰~7.9‰, 7.0‰~7.8‰, 6.6‰~8.2‰ for rhyolite from Zhongfencun Formation, trachyandesite from Chisha Formation and rhyolite from Kedoushan, respectively. From Zhongfencun Formation to Chisha Formation and Kedoushan Formation, the values of εHf(t) and δ18O are slightly increased. Comprehensive researches suggest that sources of the volcanic rocks from the Zhongfencun Formation, Chisha Formation and Kedoushan Formation are similar. They were formed by the mixing of minor magma derived from enriched lithospheric mantle and major magma derived from Neoproterozoic juvenile crust. From 148~133Ma to 132~126Ma, the region had experienced a tectonic transition from a subducting regime to a lithosphere extensional regime, and the tectonic transition happened at about 132Ma.
Key words: Volcanic Rocks     Zircon     Hf-O isotopes     Mesozoic     Fanchang basin     The Middle-Lower Yangtze River Belt    
1 引言

长江中下游多金属成矿带是我国东部重要的多金属成矿带之一,已发现200多个多金属矿床(点),地质学和年代学研究表明长江中下游地区矿床(点)在空间和时间上与燕山期的岩浆岩相关(常印佛等,1991; Zhai et al., 1996; Mao et al., 2006; Wang et al., 2006; 周涛发等, 20082012; 吴淦国等,2008; Yang et al., 2011; Zhou et al., 2015; Sun et al., 2015)。按照形成时代、岩浆岩类型、成矿规律、区域分布等因素,可以将长江中下游地区的岩浆活动划分为四个阶段:第一阶段148~133Ma,以高钾钙碱性侵入岩为主,与矽卡岩型和斑岩型多金属矿密切相关,主要发育在鄂东北、九瑞、铜陵和安庆等地区(邢凤鸣和徐祥,1996; 张旗等,2001; Xu et al., 2004; 杜杨松等,2007; Wang et al., 20072015; Huang et al., 2008; Ling et al., 20092011; 谢建成等,2008; Li et al., 20092013; Pirajno and Zhou, 2015);第二阶段131~127Ma,以橄榄安粗岩系火山岩和双峰式火山岩为主,与玢岩型矿床密切相关,主要发育在金牛、庐枞、繁昌、宁芜、溧水等火山盆地内(徐祥和邢凤鸣,1994; 闫峻等,2009; 侯可军和袁顺达,2010; Xie et al., 2011; 刘春等,2012; Tang et al., 2012b2013; Chen et al., 2014);第三阶段126~123Ma,以A型花岗岩为主,与中小型热液型矿相关,呈两条北东向A型花岗岩带分布在庐江-安庆和贵池-繁昌地区(Yan et al., 2008; 曹毅等,2008; 彭戈等,2012);第四阶段110~102Ma,主要为发育在宁镇地区的高钾钙碱性岩石,其成矿特征和第一阶段成矿特征相似(夏嘉生,2000; 许继峰等,2001; 张术根等,2010; Xu et al., 2002; 刘建敏等,2014)。本区岩浆岩的成因研究取得了众多成果,但是多集中在第一阶段岩浆岩,对于第二、三阶段岩浆岩研究程度相对较低,而且对第二阶段岩浆岩的研究主要集中在宁芜盆地和庐枞盆地(常印佛等,1991; 张旗等,2001; Xu et al., 20022004; Mao et al., 2006; Wang et al., 20062007; 杜杨松等,2007;曹毅等,2008; Huang et al., 2008; 周涛发等,2008; 吴淦国等,2008; 谢建成等,2008; Li et al., 20092013; 闫峻等,2009; 侯可军和袁顺达,2010; Xie et al., 2011; Yang et al., 2011; Ling et al., 20092011; Tang et al., 2012b2013; Chen et al., 2014)。

繁昌盆地是长江中下游地区沿江火山盆地之一,目前针对该盆地火山岩的研究还相对薄弱。Luo et al.(2013)的研究成果表明繁昌盆地镁铁质火山岩起源于富集岩石圈地幔并被少量地壳物质混染,长英质火山岩由演化后的镁铁质岩浆(SiO2:48%)与下地壳 深熔形成的岩浆混合后形成。袁峰等(2010)使用LA-ICPMS锆石定年,结果显示中分村组、赤沙组、蝌蚪山组和三梁山组火山岩的喷发时间在134~128Ma之间,这个时间和本地区其它盆地火山岩的喷发时间一致。Yan et al.(2008)通过蝌蚪山组玄武岩的研究认为其起源于同位素富集性质的岩石圈地幔。本课题组前期对繁昌盆地火山岩做了年代学、主量元素、微量元素、Sr-Nd同位素研究,成果见刘春等(2012),基于此本文针对这些样品,进一步开展锆石原位Hf-O同位素和U-Pb年代学研究,以期深入探讨繁昌盆地火山岩的岩石成因。 2 地质背景和样品描述

长江中下游地区位于扬子板块北缘,北部和西北部以襄樊-广济断裂、郯城-庐江断裂为界与大别造山带、华北克拉通相邻,南部以常州-阳新断裂为界与江南造山带相邻。研究表明,该区构造演化大致经历了三个主要阶段:前震旦纪基底形成阶段、震旦纪-早三叠世沉积盖层形成阶段、中三叠世以来的碰撞造山-造山后板内变形阶段(翟裕生等,1992)。前震旦纪基底主要由变质奥长花岗岩-英云闪长岩-花岗闪长岩组合、白云母石英片岩夹角闪岩组成,与沉积盖层呈角度不整合接触,沉积盖层主要包括震旦纪碎屑岩、白云岩、硅质岩和寒武纪至三叠纪海相碳酸盐岩等,第三阶段以中生代大规模岩浆活动和成矿作用为特征(常印佛等,1991)。区内发育大小不一的火山岩盆地(图 1),从西向东分别为金牛盆地、怀宁盆地、庐枞盆地、繁昌盆地、宁芜盆地、溧水盆地和溧阳盆地,这些盆地大致可以划分为两类,一类以庐枞、宁芜和溧水火山岩盆地为代表,其火山岩以中基性岩石为主,早期旋回为钙碱性系列,中晚期为碱性或橄榄安粗岩(shoshonite)系列,和大规模铁矿相关;另一类以金牛、怀宁和繁昌等较小的火山岩盆地为代表,火山喷发具有双峰式特征,酸性岩发育,属于钙碱性系列,目前尚无成矿方面的成因联系。这些特征表明,虽然盆地中的火山岩形成时代基本一致(闫峻等,2009),但这两类盆地的火山岩具有不同的成因。

图 1 繁昌地区地质简图Fig. 1 Geological map of Fanchang area

繁昌盆地位于长江中下游成矿带的中段,距铜陵70km,盆地中广泛发育中生代火山岩和火山碎屑岩,出露面积约62km2,火山岩系总厚220~2250m,早白垩纪火山岩自下而上划分为3个喷发旋回:中分村组、赤沙组、蝌蚪山组(图 1)。中分村组分为上下两段,下段主要为粉砂岩、沉凝灰岩,上段主要为粗安岩和流纹岩。赤沙组主要为粗面质和流纹质熔岩、熔火山碎屑岩及火山碎屑岩。蝌蚪山组可分为上、中、下三个岩性段,下段主要为沉火山碎屑岩、火山碎屑沉积岩和正常沉积岩,中段主要为玄武岩和安山岩,上段主要为流纹岩。

本次分析样品采自繁昌盆地中分村组下段(09FC003-2)、赤沙组(CS002-1)和蝌蚪山组上段(FC014),采样位置见图 1。中分村组流纹岩为灰白色,流纹构造清晰,镜下为斑状结构,斑晶为石英和钾长石,基质主要由隐晶质的石英和钾长石组成,具霏细结构(刘春等,2012)。赤沙组粗安岩为灰白色,块状构造,镜下具有斑状结构,斑晶主要是斜长石、碱性长石、黑云母,斜长石半自形到自形,短柱状到长条状,发育聚片双晶,斑晶大小2~5mm,碱性长石自形短柱状,主要是透长石,表面碳酸盐化,斑晶大小2~4mm,黑云母自形,解理清晰,沿解理有不透明矿物出溶,斑晶含量约为35%~40%;基质主要由斜长石、碱性长石、暗色矿物及少量石英组成。蝌蚪山组流纹岩为浅紫、肉红色,镜下具有斑状结构,斑晶以石英和碱性长石为主,自形,粒状,粒径为0.4~1.8mm,斑晶含量约10%,长石斑晶普遍发生蚀变;基质以长英质矿物为主,基质含量约为90%(闫峻等,2009)。 3 分析方法

锆石单矿物经分离(在河北省廊坊市诚信地质服务有限公司完成)后,挑选代表性颗粒制靶。锆石阴极发光(CL)图像在中国科学院地质与地球物理研究所拍摄,CL图像可以用来识别锆石的内部结构以选出适宜的测试点位。锆石激光原位U-Pb同位素和微量元素分析在合肥工业大学资源与环境工程学院质谱实验室开展,使用激光-电感耦合等离子质谱仪(LA-ICPMS)完成,激光器为GEOLAS ArF 193nm准分子激光,工作参数为:剥蚀物质载He为0.6L/min,激光脉冲频率5Hz,剥蚀孔径32μm,剥蚀时间90s,背景测量时间25s,脉冲能量密度为10mJ/cm2;测试质谱仪为Agilent 7500a,工作参数为:Rf功率1300W,进样深度5.5mm,等离子气体Ar 15L/min,辅助气体Ar 1L/min,补偿气体Ar 0.8~0.9L/min。应用NIST610 玻璃作为锆石微量元素含量外标,锆石标样91500进行同位素分馏校正,锆石标样Mud Tank作为外部年龄监控样,本实验测定的锆石标样结果(206Pb/238U加权平均年龄为1061±13Ma,MSWD=0.047,n=14)与推荐值一致。数据处理采用中国地质大学(武汉)开发的ICPMSDataCal 8.0软件完成,选取谐和度>90%的样品点进行数据分析,采用Isoplot软件绘制谐和图并计算加权平均年龄。

锆石微区原位氧同位素分析在中国科学院地质与地球物理研究所离子探针实验室的Cameca IMS-1280 型双离子源多接收器二次离子质谱仪上进行,分析方法详见李献华等(2009)。仪器质量分馏校正采用91500锆石标准(δ18O=9.9‰),测量的18O/16O比值通过VSMOW值(18O/16O=0.0020052)校正后,加上仪器质量分馏校正因子IMF 即为该点的δ18O值。锆石Hf同位素分析在中国地质大学(武汉)地质过程与矿产资源国家重点实验室进行,详细的分析方法见Liu et al.(2012),测试过程中每分析8个样品点,分析1个标准锆石91500和GJ-1。其中,91500用于同位素分馏校正,GJ-1作为监控标样。锆石Hf同位素分馏校正和积分信号区间调整等离线处理采用ICPMSDataCal 8.0进行。 4 分析结果 4.1 锆石U-Pb定年

所选锆石晶型良好,均透明,棱柱状,在CL阴极发光图像中,均显示清晰的振荡环带(图 2)。中分村组流纹岩中(09FC003-2)锆石长90~180μm,宽50~80μm;赤沙组粗安岩中(CS002-1)锆石长150~300μm,宽100~150μm;蝌蚪山组流纹岩中(FC014)锆石长60~150μm,宽50~70μm。三组样品的锆石长宽比约为2:1。锆石U-Pb测年数据见表 1,三组样品的Th/U为0.39~1.91,除3个测点的Th/U为0.39、0.47、0.47外,其余均大于0.5,且各样品的Th和U之间呈显著的正相关关系(图略),表明本次测试的锆石均为岩浆成因(Hoskin and Black, 2000)。

图 2 繁昌盆地火山岩代表性锆石的阴极发光(CL)图像和分析点位置图中数字标记为:测点号/εHf(t)/δ18O/年龄Fig. 2 CL images and measured points of zircons from volcanic rocks in Fanchang basinNumerical labels: point No./εHf(t)/δ18O/age

表 1 繁昌盆地火山岩锆石LA-ICPMS U-Pb测年数据 Table 1 Data of zircon LA-ICPMS U-Pb dating of volcanic rocks in Fanchang basin

中分村组样品测年数据点共32个,其中22个谐和206Pb/238U年龄的变化范围为129±4Ma~136±4Ma,加权平均年龄为132.1±1.5Ma(图 3a),代表了中分村组下段流纹岩的喷发时间。赤沙组样品测年数据点共21个,给出了125±4Ma~135±4Ma的206Pb/238U年龄,测点数据成群分布于U-Pb谐和曲线图中(图 3b),其中17个测点的加权平均年龄为129.1±1.8Ma,代表了赤沙组粗安岩的喷发时间。蝌蚪山组样品测年数据点共25个,数据较为分散,其中12个谐和206Pb/238U年龄变化范围是124±3.3Ma~137±4Ma,其加权平均年龄为129.5±3.3Ma(图 3c),代表了蝌蚪山组上段流纹岩的喷发时间。在蝌蚪山组样品中仅发现1颗锆石(表 1,FC014-6)年龄较老,为继承性或捕获锆石,年龄为719Ma。

图 3 繁昌盆地火山岩锆石U-Pb谐和图解Fig. 3 U-Pb isotopic concordant plots for zircons from volcanic rocks in Fanchang basin
4.2 锆石Hf-O同位素特征

锆石Hf-O同位素测试结果见表 2。中分村组流纹岩21颗锆石的Hf-O同位素测定值相对较为集中,其176Hf/177Hf=0.28250~0.28253,εHf(t)=-8.2~-5.8(t=130Ma),平均值为-7.1,δ18O=6.3‰~7.9‰,平均值为7.0‰。赤沙组粗安岩20颗锆石的Hf-O同位素测定值也相对较为集中,其176Hf/177Hf=0.28252~0.28260,εHf(t)=-6.0~-3.4(t=130Ma),平均值为-4.9,δ18O=7.0‰~7.8‰,平均值为7.4‰。蝌蚪山组流纹岩20颗锆石的Hf-O同位素组成显示出稍大的变化范围,其中2颗锆石的εHf(t)取值异常,1颗为FC014-6,其176Hf/177Hf=0.28240,εHf(t)=2.4(t=719Ma),δ18O=7.7‰,另1颗为FC014-9,其176Hf/177Hf=0.28152,εHf(t)=-41.5(t=130Ma),δ18O=7.4‰,其余锆石的176Hf/177Hf=0.28249~0.28264,εHf(t)=-7.4~-2.2(t=130Ma),平均值为-5.0,δ18O=6.6‰~8.2‰,平均值为7.7‰。三组火山岩的εHf(t)以及δ18O频谱图均显示近似“单峰”正态分布的特征(图 4)。

表 2 繁昌盆地火山岩锆石Hf-O同位素测试结果 Table 2 Zircon Hf-O isotopic analyzed results of volcanic rocks in Fanchang basin

图 4 繁昌盆地火山岩Hf-O同位素频谱图Fig. 4 Isotope spectrum of zircon εHf(t) and δ18O of volcanic rocks in Fanchang basin
5 讨论 5.1 火山岩的形成时代

野外观察到板石岭岩体与中分村组流纹岩呈侵入接触关系,板石岭岩体的形成年龄为124.9±1.7Ma(闫峻等,2012),因此,中分村组火山岩的年龄至少应大于125Ma。近年,袁峰等(2010)使用LA-ICPMS锆石U-Pb定年法对繁昌盆地中分村组粗安岩、赤沙组黑云母粗安斑岩、蝌蚪山组流纹岩和三梁山组黑云母粗面岩进行测年,获得中分村组、赤沙组、蝌蚪山组和三梁山组火山岩的形成时间分别为134.4±2.9Ma、131.3±1.8Ma、130.8±2.2Ma、128.1±3.1Ma;Tang et al.(2012a)使用LA-ICPMS锆石U-Pb定年法对繁昌盆地中分村组粗安岩、蝌蚪山组粗安岩进行测年,获得中分村组、蝌蚪山组火山岩的形成时间分别为133.0±3.2Ma、126±1Ma;闫峻等(2009)使用LA-ICPMS锆石U-Pb定年法对繁昌盆地蝌蚪山组流纹岩进行测年,获得130.7±1.1Ma的年龄。本文对繁昌盆地中分村组流纹岩、赤沙组粗面岩、蝌蚪山组流纹岩进行了LA-ICPMS锆石U-Pb测年,获得三组火山岩的形成时间分别为132.1±1.5Ma、129.1±1.8Ma、129.5±3.3Ma,在误差范围内本文和前人测试结果一致,由此可见,繁昌盆地火山岩岩浆活动的时间限制在126~134Ma期间,火山岩喷发持续时间较短,喷发时间较为集中,均为早白垩世岩浆活动的产物,最晚的火山活动稍早于繁昌盆地周边的侵入岩(闫峻等,2012)。

表 3中收集了长江中下游地区四个盆地火山岩的SHRIMP、LA-ICPMS或SIMS锆石U-Pb定年结果。从表 3及本文 所获年龄数据可以看出,尽管各盆地火山开始喷发时间稍有不同,但整个火山活动基本限制在135~125Ma间,各个盆地火山岩形成时间基本一致,均形成于早白垩世。火山活动时限的一致性表明,长江中下游中生代火山岩的形成应该具有相同的地球动力学背景。

表 3 长江中下游地区中生代火山岩的锆石测年结果 Table 3 Compilation of zircon U-Pb ages for the Mesozoic volcanic rocks in the Middle-Lower Yangtze River Belt
5.2 岩石成因 繁昌盆地蝌蚪山组玄武岩是下扬子地区晚中生代岩浆岩中最为典型的基性岩,解释为起源于富集性质的岩石圈地幔(Yan et al., 2008),岩石圈地幔的富集是由俯冲板片析出流体的交代形成(闫峻等,2003; Liu et al., 2010; Niu et al., 2015)。庐枞盆地和宁芜盆地主体为粗玄岩-粗面岩岩石组合,为幔源岩浆的产物。Tang et al.(2012b)测定的庐枞盆地砖桥组和浮山组火山岩中的锆石εHf(t)值为-13.0~6.1,岩石成因被解释为由亏损地幔、新元古洋壳和覆盖其上的沉积物的部分熔融形成。最近,Chen et al.(2014)对庐枞盆地火山岩锆石开展了系统的的Hf-O同位素研究,结果显示其εHf(t)值为-13.6~3.7,δ18O值为5.3‰~7.6‰,并据此解释岩石起源于富集地幔,该富集地幔由来源于俯冲沉积物的含水长英质熔体和源于俯冲蚀变洋壳的流体交代地幔楔橄榄岩生成。宁芜盆地火山岩锆石的Hf同位素研究结果也指示了类似的地幔源区(侯可军和袁顺达,2010; Tang et al., 2013)。因此,长江中下游地区早白垩纪时期存在受到俯冲板片的沉积物和/或蚀变洋壳析出的流体和/或熔体交代的岩石圈地幔。

中分村组火山岩主体为流纹岩,夹有少量的英安岩,其微量元素组成指示其并非蝌蚪山组玄武岩浆直接结晶分异形成,可能是底侵玄武岩浆形成的下地壳再次部分熔融的产物(刘春等,2012)。Tang et al.(2012a)在中分村组火山岩中发现了许多继承锆石,其U-Pb年龄集中在2388~2434Ma、1801~2018Ma以及772~831Ma这三个区间,除了少数测点以外,大多数继承锆石的单阶段Hf模式年龄在2.4~2.8Ga之间。Tang et al.(2012a)据此解释繁昌地区存在复杂的深部地壳物质,中分村组火山岩的源区中有太古界、古元古界和新元古界地壳物质的贡献。 中分村组流纹岩中锆石的εHf(t)值(-8.2~-5.8)低于娘娘山组火山岩中锆石的εHf(t)值(-4.2~3.8),其δ18O值(6.3‰~7.9‰)高于娘娘山组的δ18O值(6.0‰~7.6‰)(图 5),表明中分村组火山岩主体并非源于富集岩石圈地幔,而为壳源成因。虽然继承锆石指示中分村组火山岩源区存在古老的地壳物质,但下扬子出露的最古老基底为崆岭群,其锆石εHf(t)值按照平均地壳的Lu/Hf比值演化至130Ma时在-30以下(图 6张旗等, 2006ab),在安庆地区出露的古老变质基底董岭群中~2.0Ga锆石的εHf(t)值变化范围为-19.8~-5.6,~800Ma的锆石εHf(t)值变化范围为-24~4.9(张少兵和郑永飞等,2011),两个时代锆石的εHf(t)值按照平均地壳的Lu/Hf比值演化至130Ma时也都在-10以下,这远低于本次中分村组的测试数据,表明中分村组火山岩主体也并非直接源于古老地壳。扬子地块周边发育大量的新元古代岩浆岩,Wu et al.(2006)针对江南隆起带许村、休宁和歙县岩体的研究表明,这些岩体形成时代介于821~881Ma之间,锆石εHf(t)值为2.1~9.9,锆石δ18O值较高,为8.1‰~10.2‰。按照平均地壳的Lu/Hf比值演化到130Ma,εHf(t)值为-13.4~-6.6。张菲菲等(2011)对江南隆起带中段西园村和九岭花岗岩体的研究指示了相似的特征,这些岩体形成于804~823Ma,锆石εHf(t)值为-2.72~8.48,按照平均地壳的Lu/Hf比值演化到130Ma,εHf(t)值为-10.91~-0.05,全岩δ18O值较高,为9.6‰~12‰。这些岩体的成因被解释为新元古代(0.9~1.0Ga)新生地壳经过风化沉积循环后于800~880Ma再次重熔或部分熔融的结果。下扬子存在新元古代地壳增生事件,而该时期增生地壳熔融的产物——新元古代花岗岩的锆石εHf(t)值演化到早白垩世时期和中分村组火山岩非常相似,指示了新元古新生地壳可能为中分村组火山岩的主要源区物质。

图 5 繁昌盆地火山岩锆石εHf(t)-δ18O图解庐纵火山岩数据和富集地幔数据引自Chen et al.(2014),新元古花岗岩数据和新元古新生地壳数据张菲菲等(2011). 新元古新生地壳端元εHf(t)=-5.4,δ18O=9.3‰;富集地幔端元εHf(t)=-9.75,δ18O=6.2‰Fig. 5 εHf(t)-δ18O diagram for the zircons from volcanic rocks in Fancahng basinData of Luzong volcanic rocks and enrichment mantle is from Chen et al.(2014). Data of Neoproterozoic granite and Neoproterozoic juvenile crust is from Zhang et al.(2011). Neoproterozoic juvenile crust end-member: εHf(t)=-5.4,δ18O=9.3‰,enrichment mantle end-member: εHf(t)=-9.75,δ18O=6.2‰

图 6 繁昌盆地火山岩锆石年龄-εHf(t)图解崆岭群数据张旗等(2006ab),新元古花岗岩数据张菲菲等(2011),庐纵火山岩数据引自Tang et al.(2012b)Chen et al.(2014),宁芜火山岩数据侯可军和袁顺达(2010)Tang et al.(2013)Fig. 6 Age-εHf(t)diagram for the zircons from volcanic rocks in Fancahng basinData of Kongling Group is from Zhang et al.(2006ab). Data of Neoproterozoic granite is from Zhang et al.(2011). Data of Luzong volcanic rocks is from Tang et al.(2012b) and Chen et al.(2014). Data of Ningwu volcanic rocks is from Hou et al.(2010) and Tang et al.(2013)

但值得注意的是,新元古代花岗岩具有较高的锆石δ18O值(8.1‰~10.2‰,Wu et al., 2006),高于中分村组火山岩,指示了后者源区尚有低δ18O值的物质贡献。以崆岭群为代表的古老下扬子地壳物质同样具有较高的锆石δ18O值(~10‰,张旗等, 2006ab),表明古老地壳并非低δ18O值的物质贡献者。庐枞盆地幔源岩浆岩的研究指示交代富集的岩石圈地幔部分熔融形成的岩浆具有较低的δ18O值(5.3‰~7.6‰,Chen et al., 2014),考虑到繁昌盆地同时期也存在富集岩石圈地幔起源的岩浆岩—蝌蚪山组玄武岩,中分村组火山岩较低的δ18O值最为可能是其源区中有幔源岩浆的加入造成。因此,中分村组流纹岩是由富集岩石圈地幔部分熔融生成的岩浆和新元古新生地壳部分熔融生成的岩浆在源区混合后经历了辉石、角闪石、斜长石和磷灰石的结晶分异后(刘春等,2012)形成。

赤沙组粗安岩、蝌蚪山组流纹岩锆石δ18O值的变化范围和中分村组流纹岩锆石δ18O值的变化范围类似,但赤沙组粗安岩和蝌蚪山组流纹岩锆石δ18O值有逐渐升高的趋势(图 5),赤沙组粗安岩的锆石εHf(t)值为-6.0~-3.4,平均值为-4.9,蝌蚪山组流纹岩的锆石εHf(t)值除了一个测点为-41.5以外,其它取值范围是-7.4~2.4,平均值为-4.8,两者εHf(t)值都明显高于中分村组火山岩,但总体来看赤沙组和蝌蚪山组火山岩的岩浆源区和中分村组火山岩的源区应相似。以张菲菲等(2011)所测新元古花岗岩的锆石δ18O和εHf(t)的平均值指代新元古新生地壳的锆石δ18O和εHf(t)值,以Chen et al.(2014)所测砖桥玄武质粗安岩的锆石δ18O和εHf(t)的平均值指代富集地幔的锆石δ18O和εHf(t)值,建立新元古新生地壳和富集岩石圈地幔这两个端元的混合体系,见图 5。从图上可以看出,从中分村组到赤沙组再到蝌蚪山组,两个端元对火山岩源区的物质贡献比例不同,相对于赤沙组和蝌蚪山组火山岩而言,中分村组火山岩源区中富集地幔的贡献较大,而赤沙组和蝌蚪山组火山岩源区中富集地幔的贡献有所减少,新元古新生地壳的贡献有所增大。综合分析认为繁昌盆地赤沙组和蝌蚪山组火山岩的岩浆源区和中分村组火山岩岩浆源区相似,火山岩锆石δ18O和εHf(t)值的变化归因于富集地幔以及新生地壳物质对岩浆源区物质贡献的比例不同。 5.3 构造背景及地质意义

长江中下游地区晚中生代时期强烈的岩浆和成矿作用引起了广泛的关注,关于岩浆产生的构造背景一直存在争议。早在20世纪80年代,许多学者提出属于与俯冲作用有关的大陆边缘岩浆弧(吴利仁等,1982; 翁世劼等,1983; 陶奎元等,1988; 邓晋福等,1992);有的认为属于大陆裂谷岩浆作用(王东方,1986);有的认为火山岩起因于断裂重熔(徐嘉炜和童卫星,1987);王德滋等(1996)认为宁芜火山岩与基底深断裂有关,长江中下游断裂控制了火山构造洼地和火山断陷盆地的形成。近年来,不少学者根据对岩浆岩更加深入的研究,提出了加厚下地壳拆沉模式(Xu et al., 2002; 王强等,2003; 王元龙等,2004; Wang et al., 2006)、古太平洋板片平板俯冲模式(Li et al., 2013)、洋脊俯冲模式(Ling et al., 20092011; Liu et al., 2010; Sun et al., 2010)以及区域拉张背景下的壳幔相互作用模式(Yan et al., 2008; Xie et al., 20082011; Li et al., 2009)等。这些岩石成因模式对应了拉张环境下板内岩浆作用和俯冲带背景下的弧岩浆作用这两大构造背景。

繁昌盆地火山岩形成于长江中下游地区晚中生代岩浆作用的第二阶段,其岩浆源区以新元古时期增生地壳物质为主,同时存在受到大洋沉积物和/或俯冲板片析出流体和/或熔体交代形成的富集地幔的物质贡献以及少量的太古代-古元古代地壳物质的混入。虽然繁昌盆地双峰式火山岩和盆地周边的稍晚形成的A型花岗岩(闫峻等,2012)的发育表明本地区在132~126Ma期间处在一个拉张的构造环境,但源区有俯冲板片析出物质的贡献却明确地指示了132Ma以前的构造背景以俯冲带为主,表现在本地区晚中生代第一阶段岩浆岩的起源上(Ling et al., 20092011; Liu et al., 2010; Sun et al., 2010; Li et al., 2013)。因此,从148~133Ma演化至132~126Ma,本地区经历了俯冲带构造环境至拉张环境的转换,暗示了古太平洋板片的俯冲及后撤的转换时间在132Ma左右。 6 结论

(1)长江中下游繁昌盆地中分村组流纹岩、赤沙组粗安岩、蝌蚪山组流纹岩的形成年龄分别为132.1±1.5Ma、129.1±1.8Ma和129.5±3.3Ma。这三组火山岩的形成时间较为接近,都属于早白垩世岩浆作用的产物。

(2)三组火山岩的εHf(t)值分别为-8.2~-5.8、-6.0~-3.4、-7.4~-2.2,δ18O值分别为6.3‰~7.9‰、7.0‰~7.8‰、6.6‰~8.2‰,从中分村组到赤沙组再到蝌蚪山组εHf(t)、δ18O值逐渐升高。综合分析表明:中分村组、赤沙组、蝌蚪山组火山岩的源区相似,都是由新元古带新生地壳熔融形成的岩浆和少量的富集岩石圈地幔部分熔融形成的岩浆在源区混合后经历结晶分异形成。

(3)长江中下游前三个阶段岩浆岩成因和物质来源指示:从148~133Ma至132~126Ma,本地区经历了俯冲带构造环境至拉张环境的转换,暗示了古太平洋板片的俯冲及后撤的转换时间在132Ma左右。

参考文献
[1] Cao Y, Du YS, Cai CL, Qin XL, Li ST and Xiang WS. 2008. Mesozoic A-type granitoids and xenoliths in the Lujiang-Zongyang area, Anhui Province:Significance in post-collisional magmatic evolution. Geological Journal of China Universities, 14(4):565-576(in Chinese with English abstract)
[2] Chang YF, Liu XP and Wu CY. 1991. The Copper-Iron Belt of the Lower and Middle Reaches of the Changjiang River. Beijing:Geological Publishing House, 1-379(in Chinese)
[3] Chen L, Zhao ZF and Zheng YF. 2014. Origin of andesitic rocks:Geochemical constraints from Mesozoic volcanics in the Luzong basin, South China. Lithos, 190-191:220-239
[4] Deng JF, Zhao HL, Wu ZX, Lai SC, Luo ZH and Mo XX. 1992. A mantle plume beneath the north part of China continent and lithosphere motion. Geoscience, 6(3):267-274(in Chinese with English abstract)
[5] Du YS, Li ST, Cao Y, Qin XL and Lou YE. 2007. UAFC-related origin of the late jurassic to Early Cretaceous intrusions in the Tongguanshan ore field, Tongling, Anhui Province, East China. Geoscience, 21(1):71-77(in Chinese with English abstract)
[6] Hoskin PWO and Black LP. 2000. Metamorphic zircon formation by solid-state recrystallization of protolith igneous zircon. Journal of Metamorphic Geology, 18(4):423-439
[7] Hou KJ and Yuan SD. 2010. Zircon U-Pb age and Hf isotopic composition of the volcanic and sub-volcanic rocks in the Ningwu basin and their geological implications. Acta Petrologica Sinica, 26(3):888-902(in Chinese with English abstract)
[8] Huang F, Li SG, Dong F, He YS and Chen FK. 2008. High-Mg adakitic rocks in the Dabie orogen, Central China:Implications for foundering mechanism of lower continental crust. Chemical Geology, 255(1-2):1-13
[9] Li JW, Zhao XF, Zhou MF, Ma CQ, Sérgio de Souza Z and Vasconcelos P. 2009. Late Mesozoic magmatism from the Daye region, eastern China:U-Pb ages, petrogenesis, and geodynamic implications. Contributions to Mineralogy and Petrology, 157(3):383-409
[10] Li XH, Li WX, Wang XC, Li QL, Liu Y and Tang GQ. 2009. Role of mantle-derived magma in genesis of Early Yanshanian granites in the Nanling Range, South China:In situ zircon Hf-O isotopic constraints. Science in China(Series D), 52(9):1262-1278
[11] Li XH, Li ZX, Li WX, Wang XC and Gao YY. 2013. Revisiting the‘C-type adakites’of the Lower Yangtze River Belt, central eastern China:In-situ zircon Hf-O isotope and geochemical constraints. Chemical Geology, 345:1-15
[12] Ling MX, Wang FY, Ding X, Hu YH, Zhou JB, Zartman RE, Yang XY and Sun WD. 2009. Cretaceous ridge subduction along the Lower Yangtze River belt, eastern China. Economic Geology, 104(2):303-321
[13] Ling MX, Wang FY, Ding X, Zhou JB and Sun WD. 2011. Different origins of adakites from the Dabie Mountains and the Lower Yangtze River Belt, eastern China:Geochemical constraints. International Geology Review, 53(5-6):727-740
[14] Liu C, Yan J, Song CZ, Li QZ, Peng G, Shi L and Liu XQ. 2012. Geochronology and geochemistry of the Mesozoic volcanic rocks from Fanchang basin in the Middle-Lower Yangtze River:Petrogenesis and geological significance. Acta Petrologica Sinica, 28(10):3228-3240(in Chinese with English abstract)
[15] Liu JM, Yan J, Li QZ and Liu XQ. 2014. Zircon LA-ICPMS dating of the Anjishan pluton in Nanjing-Zhenjiang area and its significance. Geological Review, 60(1):190-200(in Chinese with English abstract)
[16] Liu SA, Li SG, He YS and Huang F. 2010. Geochemical contrasts between Early Cretaceous ore-bearing and ore-barren high-Mg adakites in central-eastern China:Implications for petrogenesis and Cu-Au mineralization. Geochimica et Cosmochimica Acta, 74(24):7160-7178
[17] Liu YS, Wang XH, Wang DB, He DT, Zong KQ, Gao CG, Hu ZC and Gong HJ. 2012. Triassic high-Mg adakitic andesites from Linxi, Inner Mongolia:Insights into the fate of the Paleo-Asian ocean crust and fossil slab-derived melt-peridotite interaction. Chemical Geology, 328:89-108
[18] Luo WJ, Hou T, Santosh M, Wen SH and Zhang ZC. 2013. Petrogenesis of Early Cretaceous bimodal volcanic rocks in the Fanchang Basin, SE China:An energy-constrained assimilation-fractional crystallization model. International Geology Review, 55(8):917-940
[19] Mao JW, Wang YT, Lehmann B, Yu JJ, Du AD, Mei YX, Li YF, Zang WS, Stein HJ and Zhou TF. 2006. Molybdenite Re-Os and albite 40Ar/39Ar dating of Cu-Au-Mo and magnetite porphyry systems in the Yangtze River valley and metallogenic implications. Ore Geology Reviews, 29(3-4):307-324
[20] Niu YL, Liu Y, Xue QQ, Shao FL, Chen S, Duan M, Guo PY, Gong HM, Hu Y, Hu ZX, Kong JJ, Li JY, Liu JJ, Sun P, Sun WL, Ye L, Xiao YY and Zhang Y. 2015. Exotic origin of the Chinese continental shelf:New insights into the tectonic evolution of the western Pacific and eastern China since the Mesozoic. Science Bulletin, 60(18):1598-1616
[21] Peng G, Yan J, Chu XQ, Li QZ and Chen ZH. 2012. Zircon U-Pb dating and geochemistry of Guichi intrusive rocks:Petrogenesis and deep dynamic processes. Acta Petrologica Sinica, 28(10):3271-3286(in Chinese with English abstract)
[22] Pirajno F and Zhou TF. 2015. Intracontinental porphyry and porphyry-skarn mineral systems in eastern China:Scrutiny of a special case‘Made-in-China’. Economic Geology, 110(3):603-629
[23] Sun WD, Ling MX, Yang XY, Fan WM, Ding X and Liang HY. 2010. Ridge subduction and porphyry copper-gold mineralization:An overview. Science China:Earth Sciences, 53(4):475-484
[24] Sun WL, Niu YL, Ma YX, Liu Y, Zhang GR, Hu ZX, Zhang ZW, Chen S, Li JY, Wang XL and Gong HM. 2015. Petrogenesis of the Chagangnuoer deposit, NW China:A general model for submarine volcanic-hosted skarn iron deposits. Science Bulletin, 60(3):363-379
[25] Tang HY, Zheng JP, Griffin WL, Su YP, Yu CM and Ren HW. 2012a. Complex Precambrian crustal evolution beneath the northeastern Yangtze Craton reflected by zircons from Mesozoic volcanic rocks of the Fanchang basin, Anhui Province. Precambrian Research, 220-221:91-106
[26] Tang M, Wang XL, Xu XS, Zhu C, Cheng T and Yu Y. 2012b. Neoproterozoic subducted materials in the generation of Mesozoic Luzong volcanic rocks:Evidence from apatite geochemistry and Hf-Nd isotopic decoupling. Gondwana Research, 21(1):266-280
[27] Tang YJ, Zhang HF, Ying JF, Su BX, Li XH and Santosh M. 2013. Rapid eruption of the Ningwu volcanics in eastern China:Response to Cretaceous subduction of the Pacific plate. Geochemistry, Geophysics, Geosystems, 14(6):1703-1721
[28] Tao KY, Xie JY, Ruan HH, Xie FG and Xue HM. 1988. Characteristics of the Mesozoic volcanism in the coastal margin of southeastern China. Bull. Nanjing Inst. Geol. M. R., Chinese Acad. Geol. Sci., 9(4):12-28(in Chinese with English abstract)
[29] Wang DF. 1986. On the characteristics and geological significance of strontium isotope of Mesozoic continental volacanic rocks in eastern China. Acta Petrologica et Mineralogica, 5(1):11-18(in Chinese with English abstract)
[30] Wang DZ, Ren QJ, Qiu JS, Chen KR, Xu ZW and Zen JH. 1996. Characteristics of volcanic rocks in the shoshonite province, eastern China, and their metallogenesis. Acta Geologica Sinica, 70(1):23-34(in Chinese with English abstract)
[31] Wang Q, Xu JF, Zhao ZH, Xiong XL and Bao ZW. 2003. Petrogenesis of the Mesozoic intrusive rocks in the Tongling area, Anhui Province, China and their constraint on geodynamic process. Science in China(Series D), 46(8):801-815
[32] Wang Q, Wyman DA, Xu JF, Zhao ZH, Jian P, Xiong XL, Bao ZW, Li CF and Bai ZH. 2006. Petrogenesis of Cretaceous adakitic and shoshonitic igneous rocks in the Luzong area, Anhui Province(eastern China):Implications for geodynamics and Cu-Au mineralization. Lithos, 89(3-4):424-446
[33] Wang Q, Wyman DA, Xu JF, Zhao ZH, Jian P and Zi F. 2007. Partial melting of thickened or delaminated lower crust in the middle of eastern China:Implications for Cu-Au mineralization. The Journal of Geology, 115(2):149-161
[34] Wang SW, Zhou TF, Yuan F, Fan Y, Zhang LJ and Song YL. 2015. Petrogenesis of dongguashan skarn-porphyry Cu-Au deposit related intrusion in the Tongling district, eastern China:Geochronological, mineralogical, geochemical and Hf isotopic evidence. Ore Geology Reviews, 64:53-70
[35] Wang YL, Wang Y, Zhang Q, Jia XQ and Han S. 2004. The geochemical characteristics of Mesozoic intermediate-acid intrusives of the Tongling area and its metallogenesis-geodynamic implications. Acta Petrologica Sinica, 20(2):325-338(in Chinese with English abstract)
[36] Weng SJ, Huang H and Kong QS. 1983. On petrochemical characteristics of Mesozoic volcanics and the generation of magma, Lishui, Jiangsu Province and Luzong, Anhui Province. Bull. Nanjing Inst. Geol. M. R., Chinese Acad. Geol. Sci., 4(2):63-84(in Chinese with English abstract)
[37] Wu GG, Zhang D, Di YJ, Zang WS, Zhang XX, Song B and Zhang ZY. 2008. SHRIMP zircon U-Pb dating of the intrusives in the Tongling metallogenic cluster and its dynamic setting. Science in China(Series D), 51(7):911-928
[38] Wu LR, Qi JY, Wang TD, Zhang XQ and Xu YS. 1982. Mesozoic volcanic rocks in the eastern part of China. Acta Geologica Sinica,(3):223-234(in Chinese with English abstract)
[39] Wu RX, Zheng YF, Wu YB, Zhao ZF, Zhang SB, Liu XM and Wu FY. 2006. Reworking of juvenile crust:Element and isotope evidence from Neoproterozoic granodiorite in South China. Precambrian Research, 146(3-4):179-212
[40] Xia JS. 2000. A preliminary division of lineage units of granitoid rocks in Ning-Zhen region. Jiangsu Geology, 24(2):81-86(in Chinese with English abstract)
[41] Xie GQ, Mao JW, Li RL and Bierlein FP. 2008. Geochemistry and Nd-Sr isotopic studies of Late Mesozoic granitoids in the southeastern Hubei Province, Middle-Lower Yangtze River Belt, eastern China:Petrogenesis and tectonic setting. Lithos, 104(1-4):216-230
[42] Xie GQ, Mao JW, Li XW, Chao D and Lei Y. 2011. Late Mesozoic bimodal volcanic rocks in the Jinniu basin, Middle-Lower Yangtze River Belt(YRB), East China:Age, petrogenesis and tectonic implications. Lithos, 127(1-2):144-164
[43] Xie JC, Yang XY, Du JG and Sun WD. 2008. Zircon U-Pb geochronology of the Mesozoic intrusive rocks in the Tongling region:Implications for copper-gold mineralization. Acta Petrologica Sinica, 24(8):1782-1800(in Chinese with English abstract)
[44] Xing FM and Xu X. 1996. High-potassium calc-alkaline intrusive rocks in Tongling area, Anhui Province. Geochimica, 25(1):29-38(in Chinese with English abstract)
[45] Xu JF, Wang Q, Xu YG, Zhao ZH and Xiong XL. 2001. Geochemistry of Anjishan intermediate-acid intrusive rocks in Ningzhen area:Constraint to origin or the magma with HREE and Y depletion. Acta Petrologica Sinica, 17(4):576-584(in Chinese with English abstract)
[46] Xu JF, Shinjo R, Defant MJ, Wang Q and Rapp RP. 2002. Origin of Mesozoic adakitic intrusive rocks in the Ningzhen area of East China:Partial melting of delaminated lower continental crust? Geology, 30(12):1111-1114
[47] Xu JW and Tong WX. 1987. On the problem of epicontinental arcs in East Asia. Marine Geology & Quaternary Geology, 7(4):17-28(in Chinese with English abstract)
[48] Xu X and Xing FM. 1994. Whole-rock and mineral Rb-Sr isochron ages of the three gabbros in Nanjing-Wuhu area, China. Scientia Geologica Sinica, 29(3):309-312(in Chinese with English abstract)
[49] Xu XS, Fan QC, O'Reilly SY, Jiang SY, Griffin WL, Wang RC and Qiu JS. 2004. U-Pb dating of zircons from quartz diorite and its enclaves at Tongguanshan in Anhui and its petrogenetic implication. Chinese Science Bulletin, 49(19):2073-2082
[50] Yan J, Chen JF, Yu G, Qian H and Zhou TX. 2003. Pb isotopic characteristics of late Mesozoic mafic rocks from the Lower Yangtze region:Evidence for enriched mantle. Geological Journal of China Universities, 9(2):195-206(in Chinese with English abstract)
[51] Yan J, Chen JF and Xu XS. 2008. Geochemistry of Cretaceous mafic rocks from the Lower Yangtze region, eastern China:Characteristics and evolution of the lithospheric mantle. Journal of Asian Earth Sciences, 33(3-4):177-193
[52] Yan J, Liu HQ, Song CZ, Xu XS, An YJ, Liu J and Dai LQ. 2009. Zircon U-Pb geochronology of the volcanic rocks from Fanchang-Ningwu volcanic basins in the Lower Yangtze region and its geological implications. Chinese Science Bulletin, 54(16):2895-2904
[53] Yan J, Peng G, Liu JM, Li QZ, Chen ZH, Shi L, Liu XQ and Jiang ZZ. 2012. Petrogenesis of granites from Fanchang district, the Lower Yangtze region:Zircon geochronology and Hf-O isotopes constrains. Acta Petrologica Sinica, 28(10):3209-3227(in Chinese with English abstract)
[54] Yang XN, Xu ZW, Lu XC, Jiang SY, Ling HF, Liu LG and Chen DY. 2011. Porphyry and skarn Au-Cu deposits in the Shizishan orefield, Tongling, East China:U-Pb dating and in-situ Hf isotope analysis of zircons and petrogenesis of associated granitoids. Ore Geology Reviews, 43(1):182-193
[55] Yuan F, Zhou TF, Fan Y, Huang YM and Zhang LJ. 2010. LA-ICPMS U-Pb ages of zircons from Mesozoic volcanic rocks and their significance in Fanchang basin, Anhui Province, China. Acta Petrologica Sinica, 26(9):2805-2817(in Chinese with English abstract)
[56] Zhai YS, Yao SZ, Lin XD, Zhou XR, Wan TF, Jin FQ and Zhou ZG. 1992. Fe-Cu-Au Metallogeny of the Middle-Lower Changjiang Region. Beijing:Geological Publishing House, 1-235(in Chinese)
[57] Zhai YS, Xiong YL, Yao SZ and Lin XD. 1996. Metallogeny of copper and iron deposits in the eastern Yangtse Craton, east-central China. Ore Geology Reviews, 11(4):229-248
[58] Zhang FF, Wang YJ, Fan WM, Zhang AM and Zhang YZ. 2011. Zircon U-Pb geochronology and Hf isotopes of the Neoproterozoic granites in the central of Jiangnan uplift. Geotectonica et Metallogenia, 35(1):73-84(in Chinese with English abstract)
[59] Zhang Q, Wang Y, Qian Q, Yang JH, Wang YL, Zhao TP and Guo GJ. 2001. The characteristics and tectonic-metallogenic significances of the adakites in Yanshan period from eastern China. Acta Petrologica Sinica, 17(2):236-244(in Chinese with English abstract)
[60] Zhang Q, Jian P, Liu DY, Wang YL, Qian Q, Wang Y and Xue HM. 2003. SHRIMP dating of volcanic rocks from Ningwu area and its geological implications. Science in China(Series D), 46(8):830-837
[61] Zhang Q, Wang Y, Li CD, Jin WJ and Jia XQ. 2006a. A granite classification based on pressures. Geological Bulletin of China, 25(11):1274-1278(in Chinese with English abstract)
[62] Zhang Q, Wang Y, Li CD, Wang YL, Jin WJ and Jia XQ. 2006b. Granite classification on the basis of Yb and Sr contents and its implications. Acta Petrologica Sinica, 22(9):2249-2269(in Chinese with English abstract)
[63] Zhang SB and Zheng YF. 2011. On the origin of low δ18O magmatic rocks. Acta Petrologica Sinica, 27(2):520-530(in Chinese with English abstract)
[64] Zhang SG, Li GX, Shi DF and Han SL. 2010. REE geochemistry research of Yanshanian ore-forming system in Ningzhen skarn deposit area. Journal of the Chinese Rare Earth Society, 28(5):626-632(in Chinese with English abstract)
[65] Zhou TF, Fan Y, Yuan F, Lu SM, Shang SG, Cooke D, Meffre S and Zhao GC. 2008. Geochronology of the volcanic rocks in the Lu-Zong basin and its significance. Science in China(Series D), 51(10):1470-1482
[66] Zhou TF, Fan Y and Yuan F. 2008. Advances on petrogensis and metallogeny study of the mineralization belt of the Middle and Lower Reaches of the Yangtze River area. Acta Petrologica Sinica, 24(8):1665-1678(in Chinese with English abstract)
[67] Zhou TF, Fan Y, Yuan F, Zhang LJ, Qian B, Ma L, Yang XF and Cooke DR. 2011. Geochronology and significance of volcanic rocks in the Ning-Wu Basin of China. Science China(Earth Sciences), 54(2):185-196
[68] Zhou TF, Fan Y, Yuan F and Zhong GX. 2012. Progress of geological study in the Middle-Lower Yangtze River valley metallogenic belt. Acta Petrologica Sinica, 28(10):3051-3066(in Chinese with English abstract)
[69] Zhou TF, Wang SW, Fan Y, Yuan F, Zhang DY and White NC. 2015. A review of the intracontinental porphyry deposits in the Middle-Lower Yangtze River Valley metallogenic belt, Eastern China. Ore Geology Reviews, 65:433-456
[70] 曹毅, 杜杨松, 蔡春麟, 秦新龙, 李顺庭, 向文帅. 2008. 安徽庐枞地区中生代A型花岗岩类及其岩石包体:在碰撞后岩浆演化过程中的意义. 高校地质学报, 14(4):565-576
[71] 常印佛, 刘湘培, 吴昌言. 1991. 长江中下游铜铁成矿带. 北京:地质出版社, 1-379
[72] 邓晋福, 赵海玲, 吴宗絮, 赖绍聪, 罗照华, 莫宣学. 1992. 中国北方大陆下的地幔热柱与岩石圈运动. 现代地质, 6(3):267-274
[73] 杜杨松, 李顺庭, 曹毅, 秦新龙, 楼亚儿. 2007. 安徽铜陵铜官山矿区中生代侵入岩的形成过程——岩浆底侵、同化混染和分离结晶. 现代地质, 21(1):71-77
[74] 侯可军, 袁顺达. 2010. 宁芜盆地火山-次火山岩的锆石U-Pb年龄、Hf同位素组成及其地质意义. 岩石学报, 26(3):888-902
[75] 李献华, 李武显, 王选策, 李秋立, 刘宇, 唐国强. 2009. 幔源岩浆在南岭燕山早期花岗岩形成过程中的作用:锆石原位Hf-O同位素制约. 中国科学(D辑), 39(7):872-887
[76] 刘春, 闫峻, 宋传中, 李全忠, 彭戈, 史磊, 刘晓强. 2012. 长江中下游繁昌盆地火山岩年代学和地球化学:岩石成因和地质意义. 岩石学报, 28(10):3228-3240
[77] 刘建敏, 闫峻, 李全忠, 刘晓强. 2014. 宁镇地区安基山岩体锆石LA-ICPMS U-Pb定年及意义. 地质论评, 60(1):190-200
[78] 彭戈, 闫峻, 初晓强, 李全忠, 陈志洪. 2012. 贵池岩体的锆石定年和地球化学:岩石成因和深部过程. 岩石学报, 28(10):3271-3286
[79] 陶奎元, 谢家莹, 阮宏宏, 谢芳贵, 薛怀民. 1988. 中国东南沿海中生代火山作用基本特征. 中国地质科学院南京地质矿产研究所所刊, 9(4):12-28
[80] 王东方. 1986. 中国东部某些中生代火山岩锶同位素特征及其地质意义. 岩石矿物学杂志, 5(1):11-18
[81] 王德滋, 任启江, 邱检生, 陈克荣, 徐兆文, 曾家湖. 1996. 中国东部橄榄安粗岩省的火山岩特征及其成矿作用. 地质学报, 70(1):23-34
[82] 王强, 徐继峰, 赵振华, 熊小林, 包志伟. 2003. 安徽铜陵地区燕山期侵入岩的成因及其对深部动力学过程的制约. 中国科学(D辑), 33(4):323-334
[83] 王元龙, 王焰, 张旗, 贾秀琴, 韩松. 2004. 铜陵地区中生代中酸性侵入岩的地球化学特征及其成矿-地球动力学意义. 岩石学报, 20(2):325-338
[84] 翁世劼, 黄海, 孔庆寿. 1983. 江苏溧水和安徽庐枞地区中生代火山岩系岩石化学特征及岩浆发生与演化. 中国地质科学院南京地质矿产研究所所刊, 4(2):63-84
[85] 吴淦国, 张达, 狄永军, 臧文拴, 张祥信, 宋彪, 张忠义. 2008. 铜陵矿集区侵入岩SHRIMP锆石U-Pb年龄及其深部动力学背景. 中国科学(D辑), 38(5):630-645
[86] 吴利仁, 齐进英, 王听渡, 张秀棋, 徐永生. 1982. 中国东部中生代火山岩. 地质学报,(3):223-234
[87] 夏嘉生. 2000. 宁镇地区花岗岩类岩石谱系单位的初步划分. 江苏地质, 24(2):81-86
[88] 谢建成, 杨晓勇, 杜建国, 孙卫东. 2008. 铜陵地区中生代侵入岩LA-ICP-MS锆石U-Pb年代学及Cu-Au成矿指示意义. 岩石学报, 24(8):1782-1800
[89] 邢凤鸣, 徐祥. 1996. 铜陵地区高钾钙碱系列侵入岩. 地球化学, 25(1):29-38
[90] 许继峰, 王强, 徐义刚, 赵振华, 熊小林. 2001. 宁镇地区中生代安基山中酸性侵入岩的地球化学亏损重稀土和钇的岩浆产生的限制. 岩石学报, 17(4):576-584
[91] 徐嘉炜, 童卫星. 1987. 论东亚大陆的陆缘弧问题. 海洋地质与第四纪地质, 7(4):17-28
[92] 徐祥, 邢凤鸣. 1994. 宁芜地区三个辉长岩的全岩和矿物Rb-Sr等时线年龄. 地质科学, 29(3):309-312
[93] 闫峻, 陈江峰, 喻钢, 钱卉, 周泰禧. 2003. 长江中下游晚中生代中基性岩的铅同位素特征:富集地幔的证据. 高校地质学报, 9(2):195-206
[94] 闫峻, 刘海泉, 宋传中, 徐夕生, 安亚军, 刘佳, 戴立群. 2009. 长江中下游繁昌-宁芜火山盆地火山岩锆石U-Pb年代学及其地质意义. 科学通报, 54(12):1716-1724
[95] 闫峻, 彭戈, 刘建敏, 李全忠, 陈志洪, 史磊, 刘晓强, 姜子朝. 2012. 下扬子繁昌地区花岗岩成因:锆石年代学和Hf-O同位素制约. 岩石学报, 28(10):3209-3227
[96] 袁峰, 周涛发, 范裕, 黄贻梅, 张乐骏. 2010. 安徽繁昌盆地中生代火山岩锆石LA-ICPMS U-Pb年龄及其意义. 岩石学报, 26(9):2805-2817
[97] 翟裕生, 姚书振, 林新多, 周珣若, 万天丰, 金福全, 周宗桂. 1992. 长江中下游地区铁铜(金)成矿规律. 北京:地质出版社, 1-235
[98] 张菲菲, 王岳军, 范蔚茗, 张爱梅, 张玉芝. 2011. 江南隆起带中段新元古代花岗岩锆石U-Pb年代学和Hf同位素组成研究. 大地构造与成矿学, 35(1):73-84
[99] 张旗, 王焰, 钱青, 杨进辉, 王元龙, 赵太平, 郭光军. 2001. 中国东部燕山期埃达克岩的特征及其构造-成矿意义. 岩石学报, 17(2):236-244
[100] 张旗, 王焰, 李承东, 金惟俊, 贾秀勤. 2006a. 花岗岩按照压力的分类. 地质通报, 25(11):1274-1278
[101] 张旗, 王焰, 李承东, 王元龙, 金惟俊, 贾秀勤. 2006b. 花岗岩的Sr-Yb分类及其地质意义. 岩石学报, 22(9):2249-2269
[102] 张少兵, 郑永飞. 2011. 低δ18O岩浆岩的成因. 岩石学报, 27(2):520-530
[103] 张术根, 李桂秀, 石得凤, 韩世礼. 2010. 宁镇地区燕山期矽卡岩矿床成矿系统稀土元素地球化学研究. 中国稀土学报, 28(5):626-632
[104] 周涛发, 范裕, 袁峰. 2008. 长江中下游成矿带成岩成矿作用研究进展. 岩石学报, 24(8):1665-1678
[105] 周涛发, 范裕, 袁峰, 钟国雄. 2012. 长江中下游成矿带地质与矿产研究进展. 岩石学报, 28(10):3051-3066