华北板块北缘中段早中二叠世的构造属性来自花岗岩类锆-岩石学报.PDF
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10000569/2013/029(09)298703 ActaPetrologicaSinica 岩石学报
华北板块北缘中段早中二叠世的构造属性:来自
花岗岩类锆石UPb年代学及地球化学的制约
王挽琼 徐仲元 刘正宏 赵庆英 蒋孝君
WANGWanQiong,XUZhongYuan ,LIUZhengHong,ZHAOQingYingandJIANGXiaoJun
吉林大学地球科学学院,长春 130061
CollegeofEarthScience,JilinUniversity,Changchun130061,China
20121119收稿,20130611改回
WangWQ,XuZY,LiuZH,ZhaoQYandJiangXJ2013EarlyMiddlePermiantectonicevolutionofthecentralnorthern
marginoftheNorthChinaCraton:ConstraintsfromzirconUPbagesandgeochemistryofthegranitoidsActaPetrologica
Sinica,29(9):2987-3003
Abstract Thispaperpresentspetrological,geochronologicalandgeochemicalstudyonLatePaleozoicintermediatefelsicintrusions
fromtheOndorSumTieshagaiareainInnerMongolia,whichistectonicallylocatedinthecentralnorthernmarginoftheNorthChina
CratonTheseintrusionscomprisemainlybiotitehornblendequartzdioriteandhornblendebiotitegranodioritewithabundantmafic
206 238
enclavesinfieldUPbdatingofzirconsfromthreesamplesbyLAICPMSyieldweighedmean Pb/ Uagesof2718±24Ma,
2714±13Maand2687±13Ma,respectivelyTheserockshaveSiO =6142% ~7173%,KO=310% ~511%,KO/
2 2 2
#
NaO=093~196,Mg=4254~4993,A/CNK=090~103,featuresofhighKcalcalkalineItypegranitoidsTheyalsoshow
2
strongenrichmentsinlightrareearth(LREEs)andlargeionlithophileelements(LILEs,eg,Cs,Rb,Ba,K,ThandU)and
depletionsinhighfieldstrengthelements(HFSEs,eg,Nb,TaandTi)andheavyrareearth(HREEs),withweaklynegativeEu
anomalies(Eu=055~095)Theprimarymagmaforgranitoidscouldbemainlyderivedfrompartialmeltingoftheuppercrust
δ
Themaficmicrogranularenclaves(MMEs)arebiotitediorites,characterizedbylowSiandK,enrichmentinFe,Mg,Ca,Ti,LILEs
(Rb,Cs,Sr,U)andHFSEs(Nb,Ta,Zr,Hf)whencomparedwiththehostrocks,itsprimarymagmacouldbemainlyd
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