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简介：ObjectiveThenearlyparallelN–S-trendingriftsinsouthernTibetrepresenttheE–WextensionoftheTibetPlateau.MostdatawhichconstrainedtheageoftheextensionaldeformationcomefromisotopicdatingofthedikesprobablyrelatedtotheactivityofthenearlyN–Sfaultingandmicasfromhydrothermalactivityandthelowtemperaturethermochronologyofplateauuplift.Previous

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简介：Recentdramaticadvancesintechnologiessuchascomputer,datamanagement,andcommunicationhaverevolutionizedthewaygeologistscollect,disseminate,andutilizegeosciencedata.Aftersummarizedthecharacteristicsandfusionofgeo-data,severalmajorfielddatacapturesystemsadoptedinNorthAmericahavebeenintroduced.GeoscienceinformationdisseminationanddistributionviathewebtechnologyandGISpackagehavealsobeendiscussed.Inaddition,multisourcesgeo-dataintegrationandtheirapplicationstomineralexploration,geologicalhazardriskassessment,andnationallandresourcesprotectionandutilizationhavebeenaddressedbyconcreteexamples.

简介：Yangjuan-Chuplwa节上的详细conodont分析，Xinmin，PanxianCounty，贵州省，包括四个Anisianconodont地区揭示了一个conodont序列，viz.Nicoraella德语集成通信适配器地区，Nc。kockeli地区，Paragondolella区分。地区和Neogondolellaconstricta地区。这些地区显示上面的Guanling形成从theBithynian由阶层组成到Anisian的Illyrian。Neogondolella的外观压缩一theAnisian/Ladinian边界可能在overlyingYangliujing形成的suggests。Panxian动物志保存withwell的海洋的爬行动物和鱼石块被证明属于conodontNc的更低的部分。在学习区域的kockeli地区。因此，Panxian动物志的年龄能是Anisian的earlyPelsonian。

简介：CART(Constituent-orientedageandresidencetimetheory)andPTM(Particle-trackingmethod)aretwowidelyusednumericalmethodstocalculatewaterage.Thesetwomethodsareessentiallyequivalentintheorybuttheirresultsmaybedifferentinpractice.Thedifferenceofthetwomethodswasevaluatedbyapplyingthemtocalculatewaterageinanidealizedone-dimensionaldomain.Themodelresultsbythetwomethodsareconsistentwitheachotherinthecasewitheitherspatiallyuniformflowfieldorspatiallyuniformdiffusioncoefficient.Ifweallowthespatialvariationinhorizontaldiffusion,atermcalledpseudodisplacementarisingfromthespatialvariationofdiffusioncoefficientlikelyplaysanimportantroleforthePTMtoobtainaccuratewaterage.Inparticular,ifthewaterparticleisreleasedataplacewherethediffusionisnottheweakest,thewateragecalculatedbythePTMwithoutpseudodisplacementismuchlargerthanthatbytheCART.ThissuggeststhatthepseudodisplacementcannotbeneglectedinthePTMtocalculatewaterageinarealisticocean.Asanexample,wepresentitspotentialimportanceintheBohaiSeawherethediffusioncoefficientvariesspatiallyandgreatly.

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.

简介：TheHezhengareaofGansuProvinceproducesthemostabundantmammalfossilsinChinaaswellasthewholeEurasia,anditalsoproducesotherCenozoicfossilsofdifferentanimalsandplants.Therefore,allofthemarenamedtheHezhengBiota.Mammalsareverysensitivetoenvironmentalchanges,andthustheevolutionofmammalianfaunasintheHezhengareareflectsthestrongupliftoftheTibetanPlateauduringtheLateCenozoic,whichdramaticallyaffectsenvironmentalchanges.IntheHezhengarea,micromammalsarenotveryrich,butsomeofthemstillareimportant.ItisrelativelyuncommonthatthreeprimatesarefoundfromtheMiddleMioceneandtheEarlyPleistocenedeposits.SincetheMiddleMiocene,carnivoreshavebecomeimportantcomponentsintheecosystemoftheHezhengarea,anddominatedintheEarlyPleistocene.TheMiddleMioceneisatimeofhighdiversityforProboscidea,characterizedbyshovel-tuskedelephants.PerissodactylsintheHezhengareaareveryabundant,especiallyLateOligoceneandLateMiocenerhinocerosesaswellastheLateMioceneandEarlyPleistocenehorses.FromtheMiddleMiocene,artiodactylsbecameimportantcomponentsofthemammalianfaunas,especiallybovids.

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简介：Dulaerqiao花岗石在在Erguna山岳和Xingan山岳之间的Xinlin-Xiguitu-Toudaoqiao缝术地区被定位，内部蒙古的东北。岩石主要由K长石，石英，和斜长石组成。这花岗石在晚含碳的时期被扔的锆石LA-ICP-MSU-Pb数据表演(308.7条獥？

简介：Jianglang山位于华南褶层系统，Jiangshan-Shaoxing深破裂地区和Baoan-Xiakou-Zhangcun破裂地区的过渡地区。形成Xiakou盆被土佬归因于拉开差错消沉

简介：Inthisstudy,changesinArcticseaicethicknessforeachiceagecategorywereexaminedbasedonsatelliteobservationsandmodelledresults.InterannualchangesobtainedfromIce,Cloud,andLandElevationSatellite(ICESat)-basedresultsshowathicknessreductionoverperennialseaice(icethatsurvivesatleastonemeltseasonwithanageofnolessthan2year)uptoapproximately0.5–1.0mand0.6–0.8m(dependingoniceage)duringtheinvestigatedwinterandautumnICESatperiods,respectively.Pan-ArcticIceOceanModelingandAssimilationSystem(PIOMAS)-basedresultsprovideaviewofacontinuedthicknessreductionoverthepastfourdecades.Comparedto1980s,thereisaclearthicknessdropofroughly0.50min2010sforperennialice.Thisoveralldecreaseinseaicethicknesscanbeinpartattributedtotheamplifiedwarmingclimateinnorthlatitudes.Besides,wefigureoutthatstronglyanomaloussoutherlysummersurfacewindsmayplayanimportantroleinpromptingthethicknessdeclineinperennialicezonethroughtransportingheatdepositedinopenwater(primarilyviaalbedofeedback)inEurasiansectordeepintoabroaderseaiceregimeincentralArcticOcean.Thisheatsourceisresponsibleforenhancedicebottommelting,leadingtofurtherreductioninicethickness.

简介：Globalseismicitycatalogsaresufficientforcharacterizingdoubleseismiczones(DSZs)insubductingslabandfacilitatetoestimatelayerseparationwithoutinconsistentuncertaintiesaslocalcatalogs.PreviousstudieshaveshownthecorrelationbetweenDSZslayerseparationandplateagewhilecorrelationforthoseyoungerthan～60Maissuspicious.ThelackingofDSZswithlayerseparationlessthan10kmfurthermakesitdifficulttopreciselyestimatesuchcorrelation.Thus,weincorporateeightDSZsdatadeterminedthroughlocalseismicityintoglobally-determineddatasetandreexaminesuchcorrelation.Thebestfittingresultsshowthatbothalinearmodelandasquarerootofplateagecanmathematicallyfitthelayerseparationwell.However,itisdifficulttodistinguishthesetwomodelswhenplateageisgreaterthan～20Masincetheirdifferenceislessthan2km.However,ifextrapolationispossible,bothmodelsshouldprovidephysicalinformationthatDSZswillnotformifthereisnosubductinglithosphere.Asaresult,theDSZscannotbeproduceduntiltheoceaniclithosphericagebecomesgreaterthan0.9Mainthesquarerootmodelwhilethelinearmodelgivesamisleadingresult.Assuchthesquarerootmodeldemonstratestherelationshipphysicallybetterthanthelinearone,itstillneedsfurthertestinthefuturewithmoreavailabledata,nevertheless,ourstudymightalsoprovideevidenceforthesuggestionthattheplateageisaprimarycontrolfactoroftheDSZsgeometryaswellasthesubductingprocesswhichdisregardsanylocaltectonicstresses.

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简介：Sm-NdandRb-Srwhole-rockisochrondatingofthesamplesofcumulatedgabbro,diabaseandandesiticporphyritefromtheArmantaiophiolite,Xinjiang,yieldedtheagesof561±41(Ma(εNd(t)=6.1)and392±17Ma(87Sr/86Sr)i=0.7041],whichstandfortheagesofcreationandlatermetamorphismoftheophiolites,respectively,ThecreationenvironmentoftheArmantaiophiolitesseemstoaback-arcbasincausedbythesouthwardsubductionofthetheArmantaiophiloitesseemstoaback-arcbasincausedbythesouthwardsubductionofthepalaeo-AsiaOcean.

简介：EarlyOrdovicianA-typegranitesinthenortheastern(NE)SongnenBlockNEChinawerestudiedtobetterunderstandthegeodynamicsettingsinthisregion.ThisresearchpresentsnewzirconU-PbagesandwholerockgeochemicaldatafortheEarlyOrdoviciangranitesintheNESongnenBlock.ZirconU-PbdatingindicatesthatthegraniteintheCuibei,Hongxing,andMeixiareasintheNESongnenBlockformedintheEarlyOrdovicianwithagesof471-479Ma.ThegranitesshowgeochemicalcharacteristicsofhighSiO2andK2OcompositionsandlowFeOT,MgO,CaO,andP2O5compositions.TheybelongtoahighKcalc-alkalineseriesanddisplayaweakperaluminousfeaturewithA/CNKvaluesof0.98-1.14.TherockshaveaΣREEcompositionof249.98-423.94ppm,andareenrichedinLREEwith(La/Yb)Nvaluesof2.87-9.87,anddisplayobviousEuanomalies(δEu=0.01-0.29).TraceelementsofthestudiedgranitesarecharacterizedbyenrichmentinRb,Th,U,Pb,Hf,andSm,anddepletionofBa,Nb,Ta,andSr.TheydisplaygeochemicalfeaturesofhighZr+Y+Nb+Cevalues(324-795ppm)andGa/AlratiosconsistentwithA-typegranites.Basedonparticulargeochemicalfeatures,suchashighRb/Nb(7.98-24.19)andY/Nb(1.07-3.43),thestudiedA-typegranitescanbefurtherclassifiedasanA2-typesubgroup.ThisresearchindicatesthattheEarlyOrdovicianA-typegraniteswereformedbythepartialmeltingofancientcrustinanextensionalsetting.LowerSr/Yand(Ho/Yb)Nratiosindicatethatplagioclaseandamphiboleareresidualinthesource,andgarnetisabsent,implyingthatthemagmawasgeneratedatlowlevelsofpressure.Bycontrast,thecontemporaneousgranitesintheSEXing'anBlocksuggestasubduction-relatedtectonicsetting,anditsadakiticpropertyindicatesathickenedcontinentalcrust.WesuggestthatthePaleo-AsianOceanplatebetweentheXing'anandSongnenblockssubductednorthwardduringtheEarlyOrdovician.Meanwhile,theNESongnenBlockwasexposedtoapassivecontinentalmargintectonicsetting.

简介：从Lombok岛，印度尼西亚，和包围区域的paleotsunami沉积的年龄决心用210在BATAN雅加达的Pb方法。包括paleotsunami沉积，方法假定那捱过沉积的这的基本理论将导致210Pb丰富。这个方法的原则是计算210在到更深埋葬的沉积的从表面的特别沉积间隔的Pb内容累积。结果然后在以前联合起来的年里被变换成年龄或depositional时间。从GawahPudak的paleotsunami沉积的标明日期的结果(S8?？？

简介：GlobalabruptclimatechangefromMarinoansnowballEarthtogreenhouseEarth,recordedascapcar-bonateoverlainondiamictite,hadshedthefirstlightonCambrianbio-radiation.Themostdocumentedcapcar-bonatesectionsaretypicalwithcomprehensiveδ13Cneg-ativevaluesandubiquitoussedimentarystructures,suchastepee-like,sheet-cracketc.,whichareassociatedwithsuccessiveglacialeustaticvariationcausedbyisostaticreboundinshallow-waterfacies.Herewereportadeep-waterbasinalcapcarbonatesectionwithstrongnegativeδ13CvaluesinthesouthernmarginoftheQinlingOrogen,Heyu,ChengkouCounty,ChongqinginChina,whichconsistsofmassivedolostonewithabundantcarbonaceouslaminae.However,itlacksthesedimentarystructureasmentionedaboveandisoverlainbythin-beddedsiliciousshalesandcherts.AK-bentonitebedwasdiscoveredwithinthebaseofcapcarbonates,about0.7mabovethetopoftheMarinoandiamictite.Magmaticzirconsthatweresep-aratedfromtheK-bentonitebedyieldaSIMSconcordiaU-Pbageof634.14-1.9Ma（lσ,MSWDcE=0.31,ProbabilityCE=1.000,n-=20）.TheageisingoodagreementwithpreviouslyreportedTIMSU-PbagesfortheterminationofMarinoanglaciationandprovidesageochronologicalconstraintfortheEdiacaransuccessionsintheQinlingOrogen.

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简介：Considerableattentionhasbeenpaidinrecentyearstothestudyofgeothermalhistorybyusingspontaneousfissiontracksof238Urecordedinminerals.Apatiteandzirconwereusedforfissiontrackstudyinthispaperbecauseapatitiehasbeenwidelyusedasanaturalgeothermometer(WangShichengetal.,1994)torevealthethermalevolutionofsedimentaryrocksbasedonitslowannealingtemperatureoffissiontracksandzirconischaracterizedbyaclosingtemperatureabove700℃,Thesampleswerecollectedfromferruginous,siliceousslatewallrockattheupperlevelsoftheorebodyandNb-REE-Feoresfromdeeptunnels.Theageandthermalevolutionoftheorebodywerediscussedintermsoffissiontrackcharactersandtheirlengthvariationsobservedinthecoexistingapatiteandzirconinthesamespecimen.