李敏;李敏;程银行;李艳锋;

• 1:天津地质矿产研究所

摘要(Abstract)：

为了解晚古生代西伯利亚板块南缘增生造山过程中的岩浆活动特征,对东乌旗巴彦都兰二长花岗岩岩相学、锆石U-Pb年代学、锆石Hf同位素和岩石地球化学进行了研究,并讨论了岩石成因和构造环境。锆石LA-ICP-MS U-Pb定年结果为(277.2±0.7)Ma,以正的锆石εHf(t)(6.8~14.1)为特征,具有年轻的锆石地壳模式年龄(tcDM)(865~655 Ma),属于早二叠世晚期岩浆活动产物。二长花岗岩以高钾[w(K)=3.63%~4.95%,K2O/Na2O=0.91~1.47]、富碱[w(K2O+Na2O)=7.52%~9.16%]、准铝质-弱过铝质(A/CNK=0.96~1.15)为特征;稀土元素总量较低(38.82×10-6~193.20×10-6),(La/Yb)N为3.91~23.08,轻、重稀土元素分异较明显,呈弱负铕异常(δEu为0.34~1.17);富集部分大离子亲石元素(LREE、Rb、K等);Zr弱负异常、Hf弱正异常,亏损Sr、Nb、Ta、P、Ti,显示后造山花岗岩特征。综合分析表明,巴彦都兰二长花岗岩形成于伸展的构造环境中,是贺根山洋盆闭合后的后造山阶段产物,为865~655 Ma前洋壳俯冲形成的先成地壳部分熔融而成。

关键词(KeyWords)： Ⅰ型花岗岩;早二叠世;地球化学;锆石U-Pb年龄;锆石Hf同位素

Abstract:

Keywords:

基金项目(Foundation): 中国地质调查局中国地质调查项目“内蒙古1∶5万奥尤特等六幅区调”(1212011220446)

作者(Author): 李敏;李敏;程银行;李艳锋;

Email:

DOI:

参考文献(References)：

• [1]Yakubchuk A.Architecture and mineral deposit settings of the Altaid orogenic collage:A revised model[J].Journal of Asian Earth Sciences,2004,23(5):761-779.
• [2]陈斌,赵国春,Wilde S.内蒙古苏尼特左旗南两类花岗岩同位素年代学及其构造意义[J].地质论评,2001,47(4):361-367.
• [3]Xiao Wenjiao,Windley B F,Hao Jie,et al.Accretion leading to collision and the Permian Solonker suture,Inner Mongolia,China:Termination of the central Asian orogenic belt[J].Tectonics,2003,22(6):1-21.
• [4]Li Jiyi.Permian geodynamic setting of Northeast China and adjacent regions:Closure of the Paleo-Asian Ocean and Subduction of the Paleo-Pacific Plate[J].Journal of Asian Earth Sciences,2006,26(3/4):207-224.
• [5]Jian Ping,Liu Dunyi,Krner A,et al.Time scale of an early to mid-Paleozoic orogenic cycle of the long-lived Central Asian Orogenic Belt,Inner Mongolia of China:Implications for continental growth[J].Lithos,2008,101(3/4):233-259.
• [6]廖卫华,戎嘉余,胡兆珣,等.吉林中部志留-泥盆纪生物地层、群落生态及生物古地理[J].地层学杂志,1995,19(4):241-249.
• [7]郭伟,林英铴,刘广虎.内蒙古西乌旗地区早二叠世皱纹珊瑚化石组合及其地质意义[J].吉林大学学报:地球科学版,2003,33(4):399-405.
• [8]周志广,谷永昌,柳长峰,等.内蒙古东乌珠穆沁旗满都胡宝拉格地区早-中二叠世华夏植物群的发现及地质意义[J].地质通报,2010,29(1):21-25.
• [9]Robinson P T,Zhou Meifu,Hu Xufeng,et al.Geochemical constraints on the origin of the Hegenshan Ophiolite,Inner Mongolia,China[J].Journal of Asian Earth Sciences,1999,17(4):423-442.
• [10]洪大卫,王式光,谢锡林,等.兴蒙造山带正ε(Nd,t)值花岗岩的成因和大陆地壳生长[J].地学前缘,2000,7(2):441-456.
• [11]张玉清,许立权,康小龙,等.内蒙古东乌珠穆沁旗京格斯台碱性花岗岩年龄及意义[J].中国地质,2009,36(5):988-995.
• [12]张万益,聂凤军,江思宏,等.内蒙古东乌珠穆沁旗岩浆活动与金属成矿作用[M].北京:地质出版社,2009.
• [13]何付兵,徐吉祥,谷晓丹,等.内蒙古东乌珠穆沁旗阿木古楞复式花岗岩体时代、成因及地质意义[J].地质论评,2013,59(6):1150-1164.
• [14]鞠文信.东乌珠穆沁旗幅1∶25万区域地质调查报告[R].呼和浩特:内蒙古自治区地质调查研究院,2008.
• [15]程银行,李艳锋,李敏,等.内蒙古1∶5万奥尤特、东方红公社、才伦郭少、巴彦都兰、东乌旗农场、石灰窑幅区域地质矿产图[R].天津:天津地质调查中心,2014.
• [16]程银行,李艳锋,李敏,等.内蒙古东乌旗碱性侵入岩的时代、成因及地质意义[J].地质学报,2014,88(11):2086-2096.
• [17]Cheng Yinhang,Teng Xuejian,Li Yanfeng,et al.Early Permian East-Ujimqin mafic-ultramafic and granitic rocks from the Xing′an-Mongolian Orogenic Belt,North China:Origin,chronology,and tectonic implications[J].Journal of Asian Earth Sciences,2014,96(5):361-373.
• [18]Yuan Honglin,Gao Shan,Liu Xiaoming,et al.Accurate U-Pb age and trace element determinations of zircon by laser ablation inductively coupled plasma-mass spectrometry[J].Geostandards and Geoanalytical Research,2004,28(3):353-370.
• [19]Liu Yongsheng,Gao Shan,Hu zhaochu,et al.Continental and oceanic crust recycling-induced melt-peridotite interactions in the Trans-North China Orogen:U-Pb Dating,Hf isotopes and trace elements in zircons from mantle xenoliths[J].Journal of Petrology,2010,51(1/2):537-571.
• [20]Ludwing K R.Isoplot/Ex Version 3.00:A geochronological toolkit for Mircrosoft Excel[M].Berkeley:Berkeley Geochronology Centre Special Publication,2003.
• [21]耿建珍,李怀坤,张剑,等.锆石Hf同位素组成的LA-MC-ICPMS测定[J].地质通报,2011,30(10):1508-1513.
• [22]Sderlund U,Patchett P J,Veroort J D,et al.The decay constant of 176Lu determined by Lu-Hf and U-Pb isotope systematics of terrestrial Percambrian high-temperature mafic intrusions[J].Earth and Planetary Science Letters,2004,219:311-324.
• [23]Bouvier A,Vervoort J D,Patchett P J.The Lu-Hf and Sm-Nd isotopic composition of CHUR:Constrains from unequilibrated chondrites and implications for the bulk composition of terrestrial planets[J].Earth and Planetary Science Letters,2008,273:48-57.
• [24]Griffin W L,Pearson N J,Belousova E A,et al.The Hf isotope compositon of cratonic mantle:LA-MC-ICPMS analysis of zircon megacrysts in kimberlites[J].Geochemica et Cosmochimica Acta,2000,64:133-147.
• [25]Griffin W L,Wang X,Jackson S E,et al.Zircon chemistry and magma mixing,SE China:In-situ analysis of Hf isotopes,Tonglu and Pingtan igneous complexes[J].Lithos,2002,61(3/4):237-269.
• [26]吴元保,郑永飞.锆石成因矿物学研究及其对U-Pb年龄解释的制约[J].科学通报,2004,49(16):1589-1604.
• [27]Koschek G.Origin and significance of the SEM cathodoluminescence from zircon[J].Journal of Microscopy,1993,171:223-232.
• [28]Williams I S,Buick I S,Cartwright I.An extended episode of early Mesoproterozoic metamorphic fluid flow in the Reynolds Range,central Australia[J].Journal of Metamorphic Petrol.,1996,14:29-47.
• [29]李志昌,路远发,黄圭成.放射性同位素地质学方法与进展[M].武汉:中国地质大学出版社,2004.
• [30]Peccerillo A,Taylor S R.Geochemistry of Eocene calc-alkaline volcanic rocks from the Kastamonu area,northern Turkey[J].Contributions to Mineralogy and Petrology,1976,58:63-82.
• [31]Sun S S,McDonough W F.Chemical and isotopic systematic of oceanic basalts:Implications for mantle composition and processes[M]∥Saunders A D,Norry M J.Magmatism in the ocean basins.London:Geological Society Special Publication,1989.
• [32]Sylvester P J.Post-collision alkaline granites[J].Journal of Geology,1989,97:261-280.
• [33]Whalen J B,Currie K L,Chappell B W.A-type granites:Geochemical characteristics,discrimination and petrogenesis[J].Contributions to Mineralogy and Petrology,1987,95:407-419.
• [34]Eby G N.The A-type granitoids:A review of their occurrence and chemical characteristics and speculations on their petrogenesis[J].Lithos,1990,26(1/2):115-134.
• [35]Simonen A.Plutonic rocks of the Svecfennides in Finland[J].Geological Survey of Finland Bulletin,1960,189(1):100-102.
• [36]Liégeois L P,Navez J,Hertogen J,et al.Contrasting origin of post-collisional high-K calc-alkaline and shoshonitic versus alkaline and peralkaline granitoids:The use sliding normalization[J].Lithos,1998,45(1/4):1-28.
• [37]张旗,钱青,王焰.造山带火成岩地球化学研究[J].地学前缘,1999,6(3):113-120.
• [38]李晓勇,郭峰,王岳军.造山后构造岩浆作用研究评述[J].高校地质学报,2002,8(1):68-78.
• [39]杨坤光,杨巍然.碰撞后的造山过程及造山带巨量花岗岩的成因[J].地质科技情报,1997,16(4):16-22.
• [40]Bechelor R A,Bowden P.Petrogenetic interpretation of granitoid rock series using multicationic parameters[J].Chemical Geology,1985,48:43-55.