简介：ThisstudyfocusesonthebasementstructureoftheParanáBasininSouthAmerica,basedongeologicalandgeophysicaldata.ItisalargeintracratonicbasinformedfromtheLateOrdovicianuntiltheCretaceous,whenasequenceofcontinentalfloodbasaltseruptionscoveredtheentirebasin,precedingthebreak-upofWesternGondwana.Isostaticmodelingwasappliedtolargegravitysurveyscomprisingmorethan12,000gravitystations.TheresidualBougueranomalypattern,representingthecrustalcontributionofthecrystallinebasement,aswellasthesedimentaryandvolcaniclayersofthebasin,revealssimilaritiesbetweenthebasementgravitysignatureandtheexposedrock.ThestresspatternsoftheLateOrdovicianandCretaceoustectoniceventspresentageographicallycoincidentmaximum,andthecorrelationbetweengravityhighsandthemainattenuation(betafactor)suggeststhepresenceofsomepreexistentsuturezones.TheresultantmosaicofgravityblocksandthelocationofmajorfaultsgivesupporttothepresenceofanimportantProterozoiccratonicfeature,herereferredtoasParanapanemablock.

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简介：TheNorthChinablock,thewesternportionoftheSino-KoreanCraton,isroundedbyYanshanianinthenorthandQinling-Dabieorogenicbeltsinthesouth.Thewidespreaddevelopmentofextensionalbasinsinthisblockindicateshorizontalextensionorcontinuedthinningofapreviouselythickened,trnstablelithospherethroughouttheMesozoic.Inthispaper,weattempttosimulatenumericallythegeodynamicalprocessofthebasinformationbyusingthemountain-basinevolutionsystem.WeassumethattheformationofnumeroussedimentarybasinsintheNorthChinablockistheresultofthecrustalextension,whichdestructsrapidlythepreviouslythickenedcrust.

简介：ThenorthernmarginoftheAlxablockisthejunctionofatectonicunits.Fourfirst-ordertectonicunitsaredistinguished:1.theYaganstructuralzonecharacteristicofanimmatureislandarc;2.theZhusileng-Hangwulastructuralzone,whichwasapassivecontinentalmarginintheEarlyPalaeozoicandwastransformedintoanactivecontinentalmarginintheLatePalaeozoic;3.theShalazhastructuralzonecharacteristicofamatureislandarc;4.theNuru-Langshanstructuralzone,whichwasaProterozoicorogenicbeltandlaterevolvedintoanextensionaltranstionalcrustinthePalaeozoic.Theabove-mentionedtectonicunitsdifferremarkablyinsedimentaryformations,magmaticrockassociations,metamorphismandgeochemistryandareboundedbyfaultsbetweenoneanother.

简介：MultistagesuperimposeddeformationhasbeendiscussedsystematicallybasedontheprogressofthestratigraphicsequencesofthenortheasternmarginofYangtzeBlock.Thenew-discoveredfirststagedeformationofthosesequencesoccurredfromthemiddleTriassictotheendofearlyJurassictogetherwithdevelopmentofregionalfolding,whichwasresultedfromthedeepdetachmentshearingtendingtowardNW-WNW.Thefoldsdiptoeastandfalldowntowardwest,andweresuperimposedbythemainstagefolding.Thereafter,aseriesoffoldsweredevelopedwithaxestrendingtowardnortheast.Consequentlynormalfoldsoccurredonthenormallimbswhileoverturnedfoldontheoverturnedlimbsduringthefirststagefolding.ThedetachmentorthrustwasformedfromlateJurassictoearlyCretaceous.DuetotheupliftingofDabieandtheWannanMountainsinthenorthandsouthsides,thebi-directionalthrustingbeltwasformedbygravityflowingfromtheMountainstowardthecenterofthebasinalongthenorthsideofXuanchengandsouthsideofGuichi.Thedeformationgeodynamicswasdiscussedsimplybasedonthenewlyrecognizedinformationaboutthetectonicevolution.

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简介：WesimulateGPShorizontalvelocityfieldintermsofrotationsofcrustalblockstodescribedeformationbehavioroftheChinesemainlandanditsneighboringareas.31crustalblocksareboundedprimarilyby~30Quaternaryfaultswithdistinctgeometriesandvariablelong-termratesof<20mm/a,and1683GPSvelocitiesweredeterminedfromdecade-longobservationsmostlywithanaverageduncertaintyof1?2mm/a.WedefineGPSvelocityatasitebythecombinationofmotionofrigidblockandelasticstraininducedbythefaultthatislockingduringaseismiccycle.ModelvelocitiespredictedfromthepreferableblockmodelmatchwellwiththeGPSvelocitiestoanuncertaintyof~1.7mm/a.Theslipratesinferredfromthismodelisinarangeof6?18mm/aforthemajorfaultsinTibetanditsmarginsand1?4mm/aineasternChina,consistentwithgeologicalobservations.Ournumericalsimulationsuggeststhatthecrustalblocksdeforminternallyatalevelof~10×10-9/a,quitesmallincomparisonwithsignificantdeformationlocalizedalongfaultzonesof50?100kmwide.Weconcludethatthepatternofcontinentaldeformationisnotcontinuous-likebutblock-like,andthetenetofplatetectonicsmaybeapplicabletocharacterizetheactivedeformationinAsia.

简介：在这篇论文，把粗野错误(空铅)的伪精确的察觉与不连续的变丑positive分析相结合的一个新想法，向前被带划分地区性的活跃的块。方法能为与观察数据缺乏的区域改进活跃的块的分界并且提供一列新火车直为活跃的块的地区性的变丑的完全的学习。另外，把四川云南区域用作例子，方法的实践过程简短被介绍。

简介：Thispapermainlydealswiththesimulationonthestrengthoftheconcretearmorblockinmodeltest.Accordingtotherequirementforthestrengthofblocksinmodelswithvariousscales,thecomponentsofmaterialsformodelblocksandtheirproportionsaredetermined.Thefailureofarmorblocksonrubble-moundbreakwatersisreproducedbymodeltests.

简介：沉积负担在河的词法进化起一个主要作用。因此，和水力的结构的沉积负担相互作用的分析具有主要重要性以便提高鱼产地和河的保藏词法特征。现在的学习处于实时的床条件一个块斜面下游地分析scour机制，当来临的流动供应的沉积被从scour洞搬运的沉积平衡时。实验在scour几何学上在模型斜槽和来临的沉积集中的效果被执行被分析。scour特征深深地取决于来临的沉积集中，这被观察，四种主要侧面配置被区分。试验性的数据被分析，实验关系被形成以便为不同水力、几何的条件从斜面脚趾评估一个scour洞，沙丘高度和最大的沙丘高度的横过的节的距离的深度和长度。一个scour洞的动态平衡形状不取决于沉积负担时间历史，这也被证明。

简介：Basedonthedatafromrepeatedpreciselevelingandacross-faultdeformationmeasurementscarriedoutinrecent30yearsandtheanalyzedresultsfromGPSobservationsmadeinrecentyearsalongthenortheasternmarginofQinghai(Xizangblock,andcombinedwiththegeologicalstructuresandseismicactivities,somecharacteristicsinregionaltectonicdeformationandstrongearthquakedevelopmentarestudiedandapproachedpreliminarily.Theresultsshowthat:a)Thespace-timedistributionofcurrenttectonicdeformationinthisareaisinhomogeneouswithrelativelyintensivetectonicdeformationinthevicinityofmainboundaryfaultsandweakdeformationinthefartherareas.Theintensityofverticaldifferentialmovementandthedeformationstatusvarywithtime,andthehorizontalmovementanddeformationarecharacterizedbyapparentcompressionandstrike-slip.b)ThetectonicstressfieldgeneratedbytheNE-trendingcontinuouscompressivemovementofQinghai(XizangblockduetothenorthwardpressandcollisionofIndiaplateistheprincipalstressforthetectonicdeformationandearthquakedevelopmentinthisarea.Theevolutionofspace-timedistributionoftectonicdeformationandseismicityiscloselyrelatedtotheblockactivityanddynamicevolutionofregionaltectonicstressfield.c)Theverticaldeformationupliftandhigh-gradientdeformationzonesandtheobviousfaultdeformationanomalyappearedalongtheboundariesoftectonicblockscanbeconsideredastheindicatorsofhinderedblockmotionandintensifiedtectonicstressfieldforstrongearthquakedevelopment.Usually,theabove-mentionedphenomenawouldbefollowedbytheseismicityofM(6.0,buttheearthquakemightnotoccurintheplacewiththemaximummovement.Thezoneswiththefaultdeformationanomalycharacterizedby(tendenciousaccumulationaccelerationturning(andthesurroundingareasmightbethepositionsforaccumulationofstrainenergyanddevelopmentandoccurrenceofstrongearthquakes.

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：源自陆地的siliciclastic的一个序列在Baxiandun外面摇庄稼，Qingdao，在在诺思中国之间的中生代collisional边界附近，块(网络控制块)和华南堵住(SCB)。这些低档变形了siliciclastic岩石被greywacke与页岩统治，manganiferous有细密纹理的沙岩，arkose和集团企业层。关于这些岩石的形成有二基本解释。一个人认为这个序列在网络控制块以内被形成，并且是白垩纪Laiyang组和Qingshan组的部分河的外形和暴烈的碎片外形出现在山东地区性的地质的地图上。另一条意见建议这些岩石表示在斜坡和盆外形的混浊depositional系统主要在奥陶纪被扔。重要地基于地观察，petrological分析，和大多数，在这的geochemical结果学习，在Baxiandun节的沉积阶层主要由siltstone，沙岩和mudstone岩性学组成。他们被深海的碎片和混浊存款在一个湖的斜坡和底统治。在Baxiandun节岩石标明日期的U-Pb由岩屑形成的锆石显示来源岩石是很复杂的，他们的年龄被改变从对早白垩纪太古代。源自陆地的岩屑的最年轻的年龄能代表沉积阶层的年龄。因此，我们推断沉积岩石属于早白垩纪深海的湖的沉积序列并且从SuluUHPorogen和华南块边缘的侵蚀有多重来源origined。

简介：Unsaturatedradionuclidemigrationexperimentswereconductedinapitinsidethetestinghall.Severaltypesofradionuclideswereusedintheexperiments.Tritiumwasusedasatracerforwatermovementinunsaturatedloess.Otherkindsofradionuclideswerealsousedinordertoobtainfundamentalparametersforradionuclidemigrationsothatfurtherenvironmentalassessmentoflow—levelradioactivewastedisposalcanbecar-riedout.Mechanismsgoverningunsaturatedflowinloess,thatis,principlesofone—waylateralflow,arepresentedqualitativelyinthispaper.Andacontinuumone—dimensionalmodelforradionuclidemigrationtestingisdevelopedbasedontheex-perimentsconductedundertheparticularconditionsatthetestsite.Thedatameasuredfromthetestswerecomparedwithsolutionsofthisone—dimensionalmodel.Resultsshowthatthismodelisfeasibleformodelingradionuclidemigrationinunsaturatedloess.

简介：Basedontheone-dimensionalsalinitytransportequationwithconstantdiffusioncoefficient,andseparatedwaterflowvelocityintorunoffandtidalcurrentwiththesingle-frequencyinanidealizedestuary,thesimplestunsteadyanalyticalsolutionofsalinityintrusionisdeducedandtheestimationformulaofdiffusioncoefficientisobtainedinthispaper.Theunsteadysolutionindicatesthatsalinityprocessinestuariesresultsfromtheinteractionofrunoffandtidalcurrent,anditsamplitudeisindirectproportiontotheproductofthevelocityofrunoffwaterandtheamplitudeoftidalflowvelocityandininverseproportiontothediffusioncoefficientandthetidalangularfrequency,anditsphaselagtidalflowwithπ/2whichrevealsthebasicfeaturesofthemaximumsalinityappearingafterfloodslackandtheminimumsalinityappearingbeforeebbslackundertheeffectofrunoff(theadvanceorlagtimeisrelativetothemagnitudeofrunoffandtidalflow).Accordingtothemeasuredflowvelocityandsalinitydata,thesalinitydiffusioncoefficientcouldbeestimated.Finally,withthefielddataofobservingsitesonthedeepwaternavigationchanneloftheYangtzeEstuary,thediffusioncoefficientiscalculatedandacomparativeanalysisofsimulatedandmeasuredofsalinityprocessismade.Theresultsshowthatthesolutioncancomprehensivelyreflectsthebasiccharacteristicsandprocessesofsalinityintrusionundertheinteractionofrunoffandtidalflowinestuaries.Thesolutionisnotonlysuitablefortheoreticalresearch,butalsoconvenientforestimatingreasonablephysicalparametersandgivingtheinitialconditioninthesalinityintrusionnumericalsimulation.

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简介：<正>Potashisoneofthelong-termscaredepositsinChina,andpotashprospectinghaslongbeenlistedasakeybrainstormprojectforournationandgeologicalprospectingunits.TherehavebeenconsiderablestudiesinsearchforpotashdepositsintheKuqadepressionoftheTarimbasin(Jacksonetal.,1991;Gemmeretal.,2004;Vendeville,2005;VendevilleandJackson,1992a,1992b),

简介：CarboncycleisconnectedwiththemostimportantenvironmentalissueofGlobalChange.Asoneofthemajorcarbonreservoirs,oceansplayanimportantpartinthecarboncycle.Inrecentyears,ironseemstogiveusagoodnewsthatoceanicironfertilizationcouldstimulatebiologicalproduc-tivityasCO2sinkofhuman-producedCO2.Oceanicironfertilizationexperimentshaveverifiedthataddingironintohighnutrientlowchlorophyll(HNLC)seawaterscanincreasephytoplanktonproductionandexportorganiccarbon,andhenceincreasecarbonsinkofanthropogenicCO2,toreduceglobalwarming.Insixtydays,theexportorganiccarboncouldreach10000timesforaddingironbymodelpredictionandinsituexperiment,I.e.TheatmosphericCO2uptakeandinorganiccarbondrawdowninupperseawatersalsohavethesamemagnitude.Therefore,oceanicironfertilizationisoneofthestrate-giesforincreasingcarbonsinkofanthropogenicCO2.Thepaperisfocusedontheironfertilization,es-peciallyinsituoceanironexperimentsinorderthatthefutureresearchismoreefficient.

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简介：UsingpureSwavefittingmethod,westudiedtheshearwavevelocitystructuresundertheOrdosblockanditseasternandsouthernmarginalareas.TheresultsshowthatthevelocitystructurebeneathYulinstationintheinteriorofOrdosblockisrelativelystable,wherenoapparentchangebetweenhighandlowvelocitylayersexistsandtheshearwavevelocityincreasessteadilywiththedepth.Thereisa12kmthicklayeratthedepthof25kmunderthisstation,withanSwavevelocity(Vs=3.90km/s)lowerthanthatatthesamedepthinitseasternandsouthernareas(Vs≥4.00km/s).ThecrustundertheeasternmarginofOrdosblockisthickerthanthatoftheYulinstation,andthevelocitystructuresalternatebetweenthehighandIowvelocitylayers,withmorelowvelocitylayers.Ithasthesamecharacteristicashavinga10km-thicklowvelocitylayer(Vs=3.80km/s)inthelowercrustbutburiedatadepthofabout35km.Moreover,westudiedtheVi/VsratioundereachstationincombinationwiththeresultofPwavevelocityinversion.Theresultsshowthat,theaveragevelocityratiooftheYulinstationattheinteriorofOrdosblockisonly1.68,withaverylowratio(about1.60)intheuppercrustandastableratioofabout1.73inthemidandlowercrust,whichindicatesthemediaunderthisstationishomogenousandstable,beinginastateofrigidity.ButatthestationsintheeasternandsouthernmarginsoftheOrdosblock,severallayersofhighvelocityratio(about1.80)havebeenfound,inwhichtheaveragevelocityratiounderKelanandLishistationsattheeasternmarginissystemicallyhigherthanthatofthegeneralelasticalbodywaves(1.732).Thisreflectsthatthecrustunderthemarginalareasismoreactiverelatively,andothermaterialsmayexistintheselayers.Finally,wediscussedtherelationshipamongearthquakes,velocitystructuresbeneathstationsandfaults.