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简介：ThispaperpresentsthefirstspecificstudyoftheTh-andU-bearingminerals,whichwererecentlyfoundintheSEMediterraneanmarginofSpain(ElHoyazoarea,Almeriaprovince).ThesemineralsareREEphosphates(mainlymonazite)whichoccurasamoeboidal-to-elongateinclusions,fromaround10120μmto120μm,hostedinsinglegarnetcrystalsfromdacitelavasandmetamorphicrocksfromtheElHoyazoVolcanicComplex.ThandUcontentsarehigherthan1wt%,with3.04to5.62wt%forTh02,and0.7to1.75wt%forUO2.Bothelementsarealsofoundinxenotime(ThO2:0.24,UO2:0.27wt%).Giventhattheerosionofthevolcanicsourcerockshasgenerateda“placer-type”depositofmonazitesandsandthatgarnets(maincarriersofmonazite)arebeingcommercialised,anenvironmentalmonitoringandmanagementplanshouldbeurgentlyexecutedinthearea.

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简介：在结晶化以后沿着Yangtzecraton和他们的变形历史的西方边缘澄清变形侵入的关系，石油化学并且踪迹元素geochemical人物，标明日期的锆石虾U-Pb，和化学药品从在Kangding的Neoproterozoic变形侵入的共存的角闪石和斜长石的作文()，四川()省，和Yuanmou()，云南()省，被学习。与以前的出版数据结合了，在Yangtzecraton的西方边缘的Kangding花岗石的plutons和Yuanmou建筑群通常在一样的句号形成了，这被显示。在700妈的变形事件广泛地存在，至少在四川从Kangding区域盖住到Eshan()在中央云南的区域。而且，角闪岩外形可以代表山峰地区性的变形状况。

简介：FollowingtherecommendationoftheInternationalCommissiononStratigraphy(16votesYes[94%],1abstention,2votesnotreceived),theGlobalboundaryStratotypeSectionandPoint(GSSP)forthebaseoftheTuronianStageoftheCretaceousSystemisdefinedasthebaseofbed86oftheBridgeCreekLimestoneMemberoftheGreenhornLimestoneFormationatthewesternendoftheDenverandRioGrandeRailroadcutnearthenorthboundaryofthePuebloReservoirStateParkRecreationArea,westofPueblo,Colorado,USA.ThisGSSPhorizonisalsoexposedandprotectedintheadjacentstaterecreationarea.ItcoincideswiththefirstoccurrenceoftheammoniteWatinocerasdevonense,isinthemiddleofaglobalpositiveexcursioninCarbon-13isotopes,andisbracketedbywidespreadbentonitesthathaveyieldedagesof93to93.5Ma.

简介：Henglingguan和Beiyu变形granitoids，在Zhongtiaoshan前寒武纪的建筑群的西北分布式，包括trondhjemites和计算碱的monzogranites，与太古代的ZhaiziTTG片麻岩显示恼人的接触。并且Beiyumetamorphicgranitoids主要由trondhjemites组成，在Hujiayu背斜褶层的核心分布式。分别地，标明日期加权平均值~(207)Pb/~(206)Pb变老的数据表演的新虾锆石U-Pb是为Henglingguan变形计算碱的monzogranites和Beiyumetamorphictrondhjemites的2435.9Maand2477妈并且揭示600妈继承了的～2在magmatic锆石的核心。Whole-rockgeochemical数据显示那所有Henglingguan和Beiyu变形trondhjemitesandcalc碱的monzogranites属于遇见了铝土的中等钾、高钾的calc-alkalineseries。这些岩石被相对高的全部的碱内容描绘(Na_2O+K_2O，在to9.08%上面)，弄空的Nb，Ta，P和Ti，和衰退权利的REE模式与对高LREEs/HREEsfractionation中等(吝啬的比率(La/Yb)_n=25)。在多元素蜘蛛图的Henglingguan和Beiyumetamorphictrondhjemites显示negativeRb，Th和K异例由原始披风使正常化。Sm-Nd同位素的数据表明这些granitoids有起始的ε_(Nd)到+2.4和Nd的(t)=-1.2弄空T_(MD)=的披风模型年龄2622马马。所有thesegeochemical特征显示这些granitoids在一条大陆边缘的弧被形成，并且trondhjemites主要从少年的部分融化发源玄武岩的材料并且然而，Henglingguan变形计算碱的monzogranites源于在一条大陆边缘的弧下面在古老的外壳中材料再循环。花岗石的岩浆在他们的形成期间经历了污染和分离结晶。

简介：Geza岛弧是一个著名矿化作用集中区域，在西藏的高原的东方边缘的Sanjiang领域的部分。在最近的年里，几迟了的Yanshanian花岗石的侵入和联系存款在这个区域被发现了，在桃花源，区域是其一最大Laba铝存款。以前的研究建议预定Laba矿化作用是85±2妈。然而，granodioritic斑岩的年龄仍然保持未知。在这研究，从忍受辉钼矿的granodioritic斑岩的三件样品锆石标明日期的LA-ICP-MSU-Pb与85.00±的产生日期一起被进行了0.23妈(MSWD=0.58)，85.28±0.28妈(MSWD=1.12)，并且84.83±0.26妈(MSWD=0.79)分别地，显示这些granodioritic斑岩在∼85附近在迟了的Yanshanian形成了妈。与矿化作用的地质的特征结合了，时间地，Laba存款遗传上空间地与granodioritic斑岩被联系。另外，Laba存款的年龄与另外的迟了的Yanshanian侵入和矿化作用一致，建议矿化作用可能在在迟了的白垩纪期间的intra板extensional环境下面被产生。

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简介：TheYangshangolddepositisasuper-largefine-graineddisseminatedgolddepositlocatedinsouthernGansuProvince.ItsmetallogenicagehasbeendeterminedbyusingthecathodoluminescenceimageandionprobeU-Pbdatingtechniques.Itisfoundthatzirconsfromquartzveinletofthefine-graineddisseminatedgoldoreshowcharactersofmagmaticoriginwithprismidiomorphism,oscillatoryzoninganddominantTh/Uratiosof0.5-1.5.Threemainpopulationsofzirconsareobtained,givingaverage206pb/238Uagesof197.6±1.7Ma,126.9±3.2Maand51.2±l.3Marespectively.ThefirstagecorrespondstotheK-Arageoftheplagiogranitedike,whilethelattertwoagesindicatethatburiedCretaceousandTertiaryintrusivesexistintheorefield,suggestingthattheYangshangolddepositwasgeneticallyrelatedtothethreemagmatichydrothermalactivities.Bycontrast,zirconsfromcoarsegold-bearingquartzveinintheminingareaaremucholderthanthehostrock,indicatingthattheveinwasformedearlierandwasnotcontaminatedbylatermagmaticfluids.ItisconcludedthatthecouplingofmultiperiodichydrothermalactivitiesintheminingareahascontributedalottomineralizationoftheYangshangolddeposit.

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简介：TheXishaBlockisaminoroneintheSouthChinaSeaandanimportanttectonicunitinthenorthwesternpartoftheregion.ZirconSHRIMPU-PbagesforthreevolcanicintrusivecoresamplesfromXike-1,anexploratorywellpenetratingthebiohermsoftheXishaIslands.ThecoresamplesarefromtheMiocenereefcarbonatebedrockandarerecognizedasdark-graybiotite-hornblendegabbro,grayfne-grainedbiotitediorite,andgrayfine-grainedgranite,respectively.Zirconcathodoluminescence(CL)imagesandtraceTh,UandPbcompositionsofthezirconsshowthattheserocksareofvolcanicintrusiveorigin.ZirconSHRIMPU-Pbdatingyieldedsixgroupsofages,rangingfrom2451-1857MatoearlyCretaceous,whichindicatethattheformationandevolutionoftheXishaBlockwasaffectedbytheevolutionandclosureofNeotethysOcean,probablywithinitseasternextensionintoSouthChinaSea.Bothold,deepsourcedmaterial,includingfragmentsfromRodinasupercontinent,andrecentmantle-derivedmagmaproductscontributedtotheemergenceandformationoftheXishablock.TheSHRIMPU-PbresultsalsoprovedthatthisprocessdifferedfromthatoftheKontummassif,theHainanBlock,andtheSouthChinaBlock,butissimilartothatoftheNanshaandZhongshablocks.TheprocesswasassociatedwiththeeffectsofYanshanianmagmatisminducedbysubductionmechanismsofthePaleo-PacificPlateorthereworkingofthemultiplemagmatismssincetheEarlytomid-Yanshanian,possiblyjointlyexperiencedbytheXisha-Zhongsha-NanshaBlock.

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简介：ObjectiveThepotassicandultrapotassicrocksrelatingtotheIndia-EurasiacollisionandcontinualplateconvergencearewidelydistributedintheLhasaterrane.TheserocksareveryimportanttounderstandthedeepprocessesoftheIndia-EurasiacollisionandtheupliftandevolutionoftheTibetanPlateau.Althoughhigh-potassicvolcanicrocksarealsoexposedinthewesternLhasaterrane,theirformation

简介：ThereportednewU-Pbagebysensitivehigh-resolutionionmicroprobe(SHRIMPⅡ)onzirconwasobtainedfromatuffsampleatthebasalDoushantuoFormationintheJiuqunaosection,whichsituatedatthewesternlimboftheHuanglinganticlineintheYangtzeGorgesinZigui,Hubei,SouthChina.Eighteenspotsofzirconswereanalyzedandtheyformtwoclusters:oneincludesthreespots,withaninheritedageof784+15Ma(MSWD=0.05);theotherconsistsof15spotsandgivesaweightedmean^206pb/^238Uageof628.3±5.8Ma(MSWD=0.86).ItisthefirstSHRIMPU-PbzirconageobtainednearlythebaseoftheDoushantuoFormationofEdiacaranandrepresentsamaximumageoftheDoushantuoFormationItalsoformsanageconstraintontheupperlimitageoftheNantuo(Marinoantype)glaciation.

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简介：博格达三个山地区基性岩墙地球化学研究显示,该岩墙属亚碱性系列,为岩浆高度演化产物,轻稀土富集,不相容元素Ba,La,K相对富集,高场强元素Nb,Th,Yb相对亏损,Ti亏损不明显,Nb/Ta（平均14.1）、Zr/Hf（平均35.99）比值与原始地幔Nb/Ta（17.8）、Zr/Hf（37）比值相似,（Th/Nb）N的值大于1,Nb/La比值小于1,表明该岩墙的岩浆源自地幔,且在侵位过程中受到地壳物质的混染。本区基性岩墙的LA-ICP-MS锆石U-Pb加权平均年龄为（322.1±6.5）Ma,表明是博格达造山带岩石圈拉张减薄时的产物,反映晚石炭世早期博格达造山带处于岩石圈拉张的构造环境与动力学背景。

简介：TheTruongSonFoldBelt,locatedatthenortheasternmarginoftheIndochinaBlock,isconsideredtobetectonicallylinkedtothesubductionofthePaleotethysOceanandsubsequentcollision.SeponisoneofthemostimportantsuperlargedepositsoftheTruongSonFoldBelt.OurLA-ICP-MSzirconU-PbdatingresultsshowthatgranodioriteporphyrysamplesfromtheSepondeposithaveagesof302.1-4-2.9Ma,whichisacrucialphaseformagmatic-tectonicalactivitiesfromtheLateCarboniferoustoEarlyPermianandhasavitalinfluenceonthemineralizationofcopperandgold.ZirconfromgranodioriteporphyryyieldsεHf(t)valuesof4.32to9.64,andTDM2hasanaverageageof914Ma,suggestingthatthesourceofthegranodioriteporphyryintheregionweremainlymantlecomponentsbutunderwentmixingandcontaminationofcrustmaterials.TheCe^4+/Ce^3+valueofzirconinthegranodioriteporphyryvarysgreatlyfrom2.4to1438.29,whichshowsmagmamixingmightoccur.Consideringthecharacteristicsoftraceelementsinthezirconandthewholerockgeochemicalcharacteristicsofintrusionrocksaswellasthecharacteristicsofregionalvolcanic-sedimentaryassociation,itisindicatedthatthetectonicsettingmaybethecontinentalarcenvironment.TheSeponAu-Cudepositisderivedfromemplacementofcalc-alkalineintermediate-acidmagmawithcomingfromdeepsourcesinthesubductionprocessofthePaleotethysOcean,formingporphyryMo-Cu,skamCu-Aumineralizationandahydrothermalsedimentary-hostedAumineralizationinthewallrocks.

简介：新疆巴里坤县下涝坝一带辉长岩锆石SHRIMPU-Pb年龄测定表明,其形成年龄为(298±7)Ma,结合区域地质情况和物探成果分析,认为该辉长岩体形成时代为早二叠世。另外,辉长岩中钛含量较高,认为该辉长岩-辉绿岩对寻找钛多金属矿产具重要意义。