大兴安岭北段雅尔根楚Ⅰ型花岗岩年代学、岩石地球化学及其地球动力学意义
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摘要
对内蒙古大兴安岭北段雅尔根楚花岗岩岩体岩相学研究表明,该花岗岩岩体主要岩性组合为正长花岗岩和花岗质糜棱岩,应用锆石U-Pb LA-ICP-MS测年方法,测得的3组年龄为226.8±2.2Ma、230.2±1.3Ma和233.6±1.5Ma,表明其岩体侵位时代为晚三叠世。岩石主量元素(XRF)具有富硅、富钾的特征,A/CNK值为0.81~1.10,显示铝弱饱和,相对富集轻稀土元素、亏损重稀土元素,具有Eu负异常,微量元素相对富集大离子亲石元素,亏损高场强元素,显示岛弧性质的花岗岩特征,微量元素特征显示其为I型花岗岩。经过综合研究认为该I型花岗岩可能是在整个伸展环境下,岩石圈地幔压力降低导致地幔上涌,残余的洋壳熔融提供流体注入,从而该岩体发生侵位。
The study of the Yaergenchu granites in northern Da Hinggan Range indicates that the granites consist of syenogranite,mylonitized granite in lithology.Analysis of zircon U-Pb LA-ICP-MS dating yielded three concordant ages of 226.8±2.2Ma,230.2±1.3Ma and 233.6±1.5Ma,indicating intrusive time of the granites is the late Triassic.The chemical analyses(XRF)show that the granites have high SiO_2,K_2O contents,A/CNK ratios ranging from 0.81to 1.10.The REE patterns are characterized by enrichment of LREEs relative to HREEs with negative Eu anomalies in chondrite-normalized REE diagram.The trace elements are relatively enrichment of large ion lithophile elements(LILE),depletion of high field strength elements(HFSE).These features are similar to the island arc granites and I type granites.Integrated study shows that these I type granites formed in the whole extensional setting.The decreasing pressure of lithosphere mantle resulted in upwelling of the mantle,and the melted residual oceanic crust provided fluid,thus causing the emplacement of this pluton.
The study of the Yaergenchu granites in northern Da Hinggan Range indicates that the granites consist of syenogranite,mylonitized granite in lithology.Analysis of zircon U-Pb LA-ICP-MS dating yielded three concordant ages of 226.8±2.2Ma,230.2±1.3Ma and 233.6±1.5Ma,indicating intrusive time of the granites is the late Triassic.The chemical analyses(XRF)show that the granites have high SiO_2,K_2O contents,A/CNK ratios ranging from 0.81to 1.10.The REE patterns are characterized by enrichment of LREEs relative to HREEs with negative Eu anomalies in chondrite-normalized REE diagram.The trace elements are relatively enrichment of large ion lithophile elements(LILE),depletion of high field strength elements(HFSE).These features are similar to the island arc granites and I type granites.Integrated study shows that these I type granites formed in the whole extensional setting.The decreasing pressure of lithosphere mantle resulted in upwelling of the mantle,and the melted residual oceanic crust provided fluid,thus causing the emplacement of this pluton.
引文
程银行,杨俊泉,刘永顺,滕学建,李艳锋,彭丽娜,李影,刘洋.2012.大兴安岭敖包查干地区安山岩年代学,地球化学研究.地质调查与研究,35(2):118~127.
葛文春,吴福元,周长勇,张吉衡.2005.大兴安岭中部乌兰浩特地区中生代花岗岩的锆石U-Pb年龄及地质意义.岩石学报,21(3):749~762.
林强,元钟宽.1998.中国东北地区中生代火山岩的大地构造意义.地质科学,33(2):129~139.
林强,葛文春,吴福元,孙德有,曹林.2004.大兴安岭中生代花岗岩类的地球化学.岩石学报,20(3):403~412.
刘建峰,迟效国,赵芝,胡兆初,陈军强.2013.内蒙古巴林右旗建设屯埃达克岩锆石U-Pb年龄及成因讨论.岩石学报,29(3):827 ~839.
李伍平,路凤香.1999.钙碱性火山岩构造背景的研究进展.地质科技情报,18(2):15~18.
李锦轶,高立明,孙桂华,李亚萍,王彦斌.2007.内蒙古东部双井子中三叠世同碰撞壳源花岗岩的确定及其对西伯利亚与中朝古板块碰撞时限的约束.岩石学报,23(3):565~582.
秦克章.1998.满洲里地区印支期花岗岩Rb-Sr等时线年代学证据.岩石矿物学杂志,17(3):235~240.
佘宏全,李进文,向安平,关继东,杨勋城,张德全,谭刚,张斌.2012.大兴安岭中北段原岩锆石U-Pb测年及其与区域构造演化关系.岩石学报,28(2):571~594.
石玉若,刘敦一,张旗,简平,张福勤,苗来成,张展桥.2007.内蒙古中部苏尼特左旗地区三叠纪A型花岗岩锆石SHRIMP U-Pb年龄及其区域构造意义.地质通报,26(2):183~189.
吴福元,杨进辉,柳小明.辽东半岛中生代花岗质岩浆作用的年代学格架.高校地质学报,2005,11(3):305~317.
许文良,王枫,裴福萍,孟恩,唐杰,徐美君,王伟.2013.中国东北中生代构造体制与区域成矿背景:来自中生代火山岩组合时空变化的制约.岩石学报,29(2):339~353.
叶栩松,廖群安,葛梦春.2011.内蒙古锡林浩特、林西地区三叠纪过铝质花岗岩的成因及构造意义.地质科技情报,30(3):57~64 .
易建,魏俊浩,姚春亮,赵少卿,余存林,李青云.2012.内蒙古白音诺尔铅锌矿区三叠纪侵入岩体的发现及地质意义:锆石U-Pb年代学证据.地质科技情报,31(004):11~16.
杨俊泉,刘永顺,滕学建,程银行,赵显宗,耿建珍,张永.2012.内蒙古宾巴勒查干粗中粒正长花岗岩年代学及岩石地球化学.地质调查与研究,35(2):128~135.
张万益,聂凤军,江思宏,许东青,郭灵俊.2008.内蒙古查干敖包石英闪长岩锆石SHRIMP U-Pb年龄及其地质意义.岩石矿物学杂志,27(3):177~184.
周漪,葛文春,王清海.大兴安岭中部乌兰浩特地区中生代花岗岩的成因—地球化学及Sr-Nd-Hf同位素制约.岩石矿物学杂志,2011,30(5):901~923.
张万益,聂凤军,高延光,刘妍.2012.内蒙古查干敖包三叠纪碱性石英闪长岩的地球化学特征及成因.岩石学报,28(2):525~534 .
柳长峰,杨帅师,武将伟,张华锋.2010.内蒙古中部四子王旗地区晚二叠-早三叠世过铝花岗岩定年及成因.地质学报,84(7):1002~1016.
张维,简平,刘敦一,侯可军.2010.内蒙古中部达茂旗地区三叠纪花岗岩和钾玄岩的地球化学,年代学和Hf同位素特征.地质通报,29(006):821~832.
张连昌,英基丰,陈志广,吴华英,王非,周新华.2008.大兴安岭南段三叠纪基性火山岩时代与构造环境.岩石学报,24(4):911~920.
Boynton W V.1984.Cosmochemistry of the rare earth elements:Meteorite studies.In:Henderson P(ed).Rare Earth Element Geochemistry.New York:Elsevier,63~114.
Liegeois J P,Navez J,Hertogen J,Black R.1998.Contrasting origin of post-collisional high-K calc-alkaline and shoshonitic versus alkaline and peralkaline granitoids.The use of slidling normalization.Lithos,45:1~28.
Ludwig K R.1991.Isoplot:aplotting and regression program for radiogenic-isotope data.US Geological Survey Open-File Report,39:91~445.
Sun S S,McDonough W F.1989.Chemical and isotopic systematics of oceanic basalts:Implications for mantle composition and processes.In:Saunders A D and Norry M J(eds.).Magmatism in the Ocean Basins.Geological Society Special Publication,42:313~345.
Wiedenbeck M,Alle P,Corfu F,Griffin W L,Meier M,Oberli F,Quadt A V,Roddick J C,Spiegel W.1995.Three natural zircon standards for U-Th-Pb,Lu-Hf,trace element and REE analyses.Geostandards Newsletter,19(1):1~23.
Yuan H L,Gao S,Liu X M,Li H M,Günther D,Wu F Y.2004.Accurate U-Pb age and trace element determinations of zirconby laser ablation-inductively coupled plasma-massspectrometry.Geostandards and Geoanalytical Research,28(3):353~370.
葛文春,吴福元,周长勇,张吉衡.2005.大兴安岭中部乌兰浩特地区中生代花岗岩的锆石U-Pb年龄及地质意义.岩石学报,21(3):749~762.
林强,元钟宽.1998.中国东北地区中生代火山岩的大地构造意义.地质科学,33(2):129~139.
林强,葛文春,吴福元,孙德有,曹林.2004.大兴安岭中生代花岗岩类的地球化学.岩石学报,20(3):403~412.
刘建峰,迟效国,赵芝,胡兆初,陈军强.2013.内蒙古巴林右旗建设屯埃达克岩锆石U-Pb年龄及成因讨论.岩石学报,29(3):827 ~839.
李伍平,路凤香.1999.钙碱性火山岩构造背景的研究进展.地质科技情报,18(2):15~18.
李锦轶,高立明,孙桂华,李亚萍,王彦斌.2007.内蒙古东部双井子中三叠世同碰撞壳源花岗岩的确定及其对西伯利亚与中朝古板块碰撞时限的约束.岩石学报,23(3):565~582.
秦克章.1998.满洲里地区印支期花岗岩Rb-Sr等时线年代学证据.岩石矿物学杂志,17(3):235~240.
佘宏全,李进文,向安平,关继东,杨勋城,张德全,谭刚,张斌.2012.大兴安岭中北段原岩锆石U-Pb测年及其与区域构造演化关系.岩石学报,28(2):571~594.
石玉若,刘敦一,张旗,简平,张福勤,苗来成,张展桥.2007.内蒙古中部苏尼特左旗地区三叠纪A型花岗岩锆石SHRIMP U-Pb年龄及其区域构造意义.地质通报,26(2):183~189.
吴福元,杨进辉,柳小明.辽东半岛中生代花岗质岩浆作用的年代学格架.高校地质学报,2005,11(3):305~317.
许文良,王枫,裴福萍,孟恩,唐杰,徐美君,王伟.2013.中国东北中生代构造体制与区域成矿背景:来自中生代火山岩组合时空变化的制约.岩石学报,29(2):339~353.
叶栩松,廖群安,葛梦春.2011.内蒙古锡林浩特、林西地区三叠纪过铝质花岗岩的成因及构造意义.地质科技情报,30(3):57~64 .
易建,魏俊浩,姚春亮,赵少卿,余存林,李青云.2012.内蒙古白音诺尔铅锌矿区三叠纪侵入岩体的发现及地质意义:锆石U-Pb年代学证据.地质科技情报,31(004):11~16.
杨俊泉,刘永顺,滕学建,程银行,赵显宗,耿建珍,张永.2012.内蒙古宾巴勒查干粗中粒正长花岗岩年代学及岩石地球化学.地质调查与研究,35(2):128~135.
张万益,聂凤军,江思宏,许东青,郭灵俊.2008.内蒙古查干敖包石英闪长岩锆石SHRIMP U-Pb年龄及其地质意义.岩石矿物学杂志,27(3):177~184.
周漪,葛文春,王清海.大兴安岭中部乌兰浩特地区中生代花岗岩的成因—地球化学及Sr-Nd-Hf同位素制约.岩石矿物学杂志,2011,30(5):901~923.
张万益,聂凤军,高延光,刘妍.2012.内蒙古查干敖包三叠纪碱性石英闪长岩的地球化学特征及成因.岩石学报,28(2):525~534 .
柳长峰,杨帅师,武将伟,张华锋.2010.内蒙古中部四子王旗地区晚二叠-早三叠世过铝花岗岩定年及成因.地质学报,84(7):1002~1016.
张维,简平,刘敦一,侯可军.2010.内蒙古中部达茂旗地区三叠纪花岗岩和钾玄岩的地球化学,年代学和Hf同位素特征.地质通报,29(006):821~832.
张连昌,英基丰,陈志广,吴华英,王非,周新华.2008.大兴安岭南段三叠纪基性火山岩时代与构造环境.岩石学报,24(4):911~920.
Boynton W V.1984.Cosmochemistry of the rare earth elements:Meteorite studies.In:Henderson P(ed).Rare Earth Element Geochemistry.New York:Elsevier,63~114.
Liegeois J P,Navez J,Hertogen J,Black R.1998.Contrasting origin of post-collisional high-K calc-alkaline and shoshonitic versus alkaline and peralkaline granitoids.The use of slidling normalization.Lithos,45:1~28.
Ludwig K R.1991.Isoplot:aplotting and regression program for radiogenic-isotope data.US Geological Survey Open-File Report,39:91~445.
Sun S S,McDonough W F.1989.Chemical and isotopic systematics of oceanic basalts:Implications for mantle composition and processes.In:Saunders A D and Norry M J(eds.).Magmatism in the Ocean Basins.Geological Society Special Publication,42:313~345.
Wiedenbeck M,Alle P,Corfu F,Griffin W L,Meier M,Oberli F,Quadt A V,Roddick J C,Spiegel W.1995.Three natural zircon standards for U-Th-Pb,Lu-Hf,trace element and REE analyses.Geostandards Newsletter,19(1):1~23.
Yuan H L,Gao S,Liu X M,Li H M,Günther D,Wu F Y.2004.Accurate U-Pb age and trace element determinations of zirconby laser ablation-inductively coupled plasma-massspectrometry.Geostandards and Geoanalytical Research,28(3):353~370.