简介：The32ndsessionoftheInternationalGeologicalCongress(IGC)willbeheldinFlorence,Italy,onAugust20-28,2004.ItwillbethesecondtimeforItalytohosttheIGC,thefirstoccasionhavingbeenthe2ndIGCsession,heldinBolognain1881.Intheintervening124years,Italiangeoscienceshavemadegreatprogressandhavegainedaleadingpositioninmanyfields.SituatednearthemiddleoftheMediterraneanSea,Florencewill

简介：Thestudyshowsthatearthquake-affectedtime-spacedomain(ETSD),i.e.atime-spacerangeinwhichstrongearthquakesareunabletooccurowingtotheinfluenceofapriorearthquakeoccurring,showsahyperbolicmargincurveinthet(time)-r(distance)coordinateplane,whichhasamaximumaffectedradiusr0att=0andamaximuminfluencetimet0(i.e.theinsiturecurrenceintervalofearthquakes)atr=0.Basedonthetime-distancedistributionsofposteriorearthquakesrelativetoproronesintheregionsofNorthChina,NorthwestChina,Qinghai-Xizang(Tibet)plateauandSouthwestChina,theoptimizedand90%-confidencemargincurvesareestimatedusingoptimizationandstatisticalanalysismethods.ThisindicatesthattheconceptandmethodofETSDwith3-dimension(time-distance-magnitudes)insteadofthoseof"recurrenceinterval"with1-dimension(time)or2-dimension(time-magnitude)providesanewapproachtounderstandingthefluctuationofseismicactivities,estimatingtheeffectiveearthquake-preparationtimeofpotentialhypocenters,andthereforeimprovingthemediumandlong-termpredictionofstrongearthquakes.

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简介：为表面下的成像的一个被动地震方法的分析在周围的地震噪音作为照明的来源在哪个被采用被介绍表面下散布ers。成像算法能以引起图象背景噪音随着时间的过去减少的一种递归的方式把新数据合并到图象。在空间地支离破碎的周围的噪音的假设下面，为成像算法的点传播函数的一个分析表达式被导出。点传播函数(PSF)描绘图象的分辨率，它是收到的数组长度和周围的带宽的一个函数。

简介：有弹性的移植被采用multicomponent处理地震数据的向量广泛地付了注意。光线基于的有弹性的Kirchhoff移植有象高灵活性和高效率的如此的性质。然而，它没能解决multipath引起的许多问题。在另一方面，有弹性的反向时间的移植(请读使用手册)基于双向波浪方程被知道能够处理这些问题，但是当在3D情况和速度模型大楼中适用时，它是极其昂贵的。基于有弹性的Kirchhoff-Helmholtz积分，我们计算decoupled由介绍有弹性的格林的向后继续的wavefields为P-waves,和S波浪工作，它被elastodynamicGaussian横梁的求和表示。PP和改正极性的PS图象被计算关联在之间获得向下并且decoupled向后继续的向量wavefields，在极性修正被分析在极化之间的关系执行的地方，变换PS的方向飘动并且接口上的事件角度。到大程度，我们的方法把基于光线的移植的高效率与波浪方程的高精确性相结合基于的反向时间的移植。到从差错模型和Marmousi2的合成数据集建模的multicomponent的这个方法的申请表明新方法的有效性，灵活性和精确性。

简介：TwomethodsforsmoothingpseudorangeobservablebyCarrierandDopplerarediscussed.ThentheprocedurebasedontheRINEXobservationfilesistestedusingtheAshtechZ-XII3TgeodeticreceiversdrivenbyastableexternalfrequencyatUNSO.Thispaperproposestoadaptthisprocedureforthelinksbetweengeodeticreceivers,inordertotakeadvantageofthePcodesavailableonL1andL2.Thisnewprocedureusesthe30-secondRINEXobservationsfiles,thestandardoftheInternationalGPSService(IGS),andprocessestheionosphere-freecombinationofthecodesP1andP2;thesatellitepositionsarededucedfromtheIGSrapidorbits,availableaftertwodays.

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简介：Inordertosolvetheproblemofearlyestimationofmoderatelystrongaftershockdurationtimeinanearthquakesequence,thisstudyhasbeenconducted.First,thedefinitionofthestrongaftershockhasbeengiven.Itispointedoutthatthereisadifferenceinthestrongaftershockdurationtimebetweenthemainshocktypesequenceandthestrongearthquakeswarmsequence.Afterdividingthethreecases,i.e.,astrongaftershockdurationtimelargerthan1day,smallerthan1day,andnostrongaftershockoccurredinamainshocktypesequencebyusingthepatternrecognitionmethod,wegavetheroughcorrelationrelationbetweenstrongaftershockdurationtimeandfirstlargeshockmagnitudefortwotypesofsequences.Finally,thejudgmentindexandmethodofestimatingstrongaftershockdurationtimesfordifferentsequencetypeshavebeengiven.

简介：TheconstructionoftheGeologicTimeScale(GTS)isatitanicscientificchallengethathasbeenunderwayfortwocenturiesandwillrequiremuchdedicatedeffortinthefuture.ItalypreservesaparamountstratigraphicrecordofMesozoicandCenozoicmarinesedimentsthathavebeensignificantinthedevelopmentofthemodernGTS.TheItalianstratigraphicrecordhasbeenhistori-callyimportantinintroducinganddefiningthestandardChronostratigraphicUnits(CUs)oftheNeogeneandQuaternary.PelagicsuccessionsfromNorthernApen-ninesandSouthernAlpshavebeenusedintheseventiesforintegratingthelateCretaceous-PaleogeneGeomag-neticPolarityTimeScale(GPTS)withplanktonicmicrofossilbiostratieraohvandstandardCUs.Thiswasamajorcontributiontotheconstructionofanewgener-ationofGTSbasedonintegratedmagnetobiochronol-ogy.ThemiddleMiocenetoearlyPleistocenemarinerecordfromSicilyandsouthernItalyhasbeenfunda-mentalforestablishingtherecentlydevelopedAstro-nomicalTimeScale(ATS).Inprospect,therearemanypotentialsstilltobeexploitedintheItalianmarinestratigraphicrecordforimplementingtheGTSbydefin-ingGSSPsofvariousCUs,improvingmagneto-biochronologyandextendingdownwardstheATS.

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简介：Thispaperpresentsacopulatechniquetodeveloptime-variantseismicfragilitycurvesforcorrodedbridgesatthesystemlevelandconsiderstherealistictime-varyingdependenceamongcomponentseismicdemands.Basedonmaterialdeteriorationmechanismsandincrementaldynamicanalysis,thetime-evolvingseismicdemandsofcomponentswereobtainedintheformofmarginalprobabilitydistributions.Thetime-varyingdependencesamongbridgecomponentswerethencapturedwiththebestfittingcopulafunction,whichwasselectedfromthecommonlyusedcopulaclassesbytheempiricaldistributionbasedanalysismethod.Thesystemtime-variantfragilitycurvesatdifferentdamagestatesweredevelopedandtheeffectsoftime-varyingdependencesamongcomponentsonthebridgesystemfragilitywereinvestigated.Theresultsindicatethetime-varyingdependenceamongcomponentssignificantlyaffectsthetime-variantfragilityofthebridgesystem.Thecopulatechniquecapturesthenonlineardependenceamongcomponentseismicdemandsaccuratelyandeasilybyseparatingthemarginaldistributionsandthedependenceamongthem.

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简介：Yuhuangge()在Wushan的山崩()，重庆()，是在三座峡水库的焦点的监视地质的危险之一。时间域反射计(TDR)和在里面地方倾斜仪被安排监视深变丑。时间领域反射计基于在岩石或为这传播的思考由于扎根的变丑导致的电报畸形集体、看的土壤中播送电磁的脉搏进同轴的电报grouted。把号码5车站的监视数据比作，在山崩的中间的侧面，从6月2008的12月，深度滑动TDR决定的表面?33.58m，它与附近的地上凿穿的地质的条件一致。TDR和倾斜仪的变丑曲线趋势是类似的，并且它与三座峡水库175m引起试验性的被坝所围住的水的变丑是一致的。进一步，TDR能精确地监视微小的变丑。因此，TDR是适用的深监视Yuhuangge山崩变丑并且反映变丑特征很好。在山崩监视支持TDR的申请是重要的。

简介：InthispaperthemethodofcombiningtheBursamodeltointegrateseveralregionaltimeseriestoderiveaunifiedglobaltimeseriesisintroducedindetail.Then,anexampletakenfromCMONOC(CrustalMovementObservationNetworkofChina)isusedtotestifthecombinationmethodisfeasible.Theprecisionoftheintegratedtimeserieswiththecombinationmethodisbelow2mm(North),3mm(East),thatissameastheresultsfromthedirectintegrationofthetimeseriesandtheprecisionofthebaselineisbelow6mm,whichprovesthatthecombinationmethodcanbeusedtointegrateseveralregionaltimeseriestoderiveaunifiedglobaltimeseries.

简介：ＩｎｔｒｏｄｕｃｔｉｏｎＷｈｅｔｈｅｒｅａｒｔｈｑｕａｋｅｓｃａｎｂｅｐｒｅｄｉｃｔｅｄｏｒｎｏｔｉｓｓｔｉｌａｐｒｏｂｌｅｍｉｎｃｏｎｔｒｏｖｅｒｓｙｉｎｔｈｅｓｅｉｓｍｏｌｏｇｉｃａｌｃｉｒｃｌｅ．Ａｔａｎｙｒａｔｅ，ｈｏｗｅｖｅｒ，ｐｅｏｐｌ...

简介：聚类的地震指在时空与对方一起仔细发生的地震事件。因为他们的重叠波形记录使拣第一到达困难，聚类地震的hypocenters不能被traveltime地点方法精确地决定。这里，我们使用一个反向时间的成像(RTI)方法印射聚类地震。拿直接使用波形的优点，RTI方法是有能力的印射单个小地震或浓密地散布的一些在2-D下面聚类地震地震数组。在3-D情况中，RTI方法成功地被使用从一套稀疏地分布式的表面车站用数据定位长偏移量的马甲地震。为一样的获得几何学，然而，在印射的RTI相遇挑战浓密地散布了聚类地震。当改进印射聚类地震与照明角度的更宽的范围要求一个更稠密的接收装置网络，是明显的时，与合成数据验证RTI方法的实际分辨率是必要的。在我们在三个峡区域的学习区域，我们3-D情况的测试建议在线性排列亚数组下面的一些事件有合理分辨率。

简介：Prestackreversetimemigration（RTM）isanaccurateimagingmethodofsubsurfacemedia.TheviscoacousticprestackRTMisofpracticalsignificancebecauseitconsiderstheviscosityofthesubsurfacemedia.OneofthestepsofRTMissolvingthewaveequationandextrapolatingthewavefieldforwardandbackward;therefore,solvingaccuratelyandefficientlythewaveequationaffectstheimagingresultsandtheefficiencyofRTM.Inthisstudy,weusetheoptimaltime-spacedomaindispersionhigh-orderfinite-difference（FD）methodtosolvetheviscoacousticwaveequation.Dispersionanalysisandnumericalsimulationsshowthattheoptimaltime-spacedomainFDmethodismoreaccurateandsuppressesthenumericaldispersion.Weusehybridabsorbingboundaryconditionstohandletheboundaryreflection.Wealsousesource-normalizedcross-correlationimagingconditionsformigrationandapplyLaplacefilteringtoremovethelow-frequencynoise.NumericalmodelingsuggeststhattheviscoacousticwaveequationRTMhashigherimagingresolutionthantheacousticwaveequationRTMwhentheviscosityofthesubsurfaceisconsidered.Inaddition,forthewavefieldextrapolation,weusetheadaptivevariable-lengthFDoperatortocalculatethespatialderivativesandimprovethecomputationalefficiencywithoutcompromisingtheaccuracyofthenumericalsolution.

简介：Thenoisedatainverticalcomponentrecordsof85seismicstationsinFujianProvinceduring2012isusedastheresearchobjectinthispaper.Thenoisedataisdividedintofiveminutesegmentstocalculatethepowerspectra.Thehighreferencelineandlowreferencelineofstationarethenidentifiedbydrawingaprobabilitydensityfunctiongraph(PDF)usingthepowerspectralprobabilitydensityfunction.Moreover,accordingtotheanomaliesofPDFgraphsin85seismicstations,theabnormalnoiseisdividedintofourcategories:droppedpacket,lownoise,highnoise,andmediannoiseanomalies.Afterwards,fourselectionmethodsarefoundbythehighorlownoisereferencelineofthestations,andthesystemofreal-timemonitoringofseismicnoiseisformedbycombiningthefourselectionmethods.Noiserecordsof85seismicstationsinFujianProvinceinJuly2013areselectedforverification,andtheresultsshowthattheanomalousnoise-recognitionsystemcouldreacha90%successrateatmoststationsandtheeffectofselectionareverygood.Therefore,itcouldbeappliedtotheseismicnoisereal-timemonitoringinstations.

简介：Thispaperdealswiththepredictionofpotentiallymaximummagnitudeandorigintimeforreservoirinducedseismicity(RIS).ThefactorandsignofseismologyandgeologyofRIShasbeenstudied,andtheinformationquantityformagnitudeofinducedseismicityprovidedbythemhasbeencalculated.Intermsofinformationquan-titythebiggestpossiblemagnitudeofRISisdetermined.Thechangesofseismicfrequencywithtimearestudiedusinggreymodelmethod,andthetimeofthebiggestchangerateistakenasoriginaltimeofthemainshock.ThefeasibilityofmethodsforpredictingmagnitudeandtimehasbeentestedforthereservoirinducedseismicityintheXinfengjiangreservoir,ChinaandtheKoynareservoir,India.

简介：Inthispaper,akindofexplicitdifferenceschemetosolvenonlinearevolutionequations,perfectlykeepingthesquareconservationbyadjustingthetimestepinterval,isconstructed,fromthecomprehensivemaintenanceofthead-vantagesoftheimplicitcompletesquareconservativeschemeandtheexplicitinstantaneoussquareconservativescheme.Thenewschemesarebasedonthethoughtofaddingasmalldissipation,butitisdifferentfromthesmalldissipationmethod.Thedissipativetermusedinthenewschemesisnotasimpleartificialdissipativeterm,butaso-called(time)harmoniousdissipativetermthatcancompensateforthetruncationerrorsfromthedissociationofthetimedifferentialterm.Therefore,thenewschemesmayhaveahightimeprecisionandmayacquireasatisfactoryeffectinnumericaltests.