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89 个结果
  • 简介:本文以地震带为统计单元,采用检验历史地震完整性的统计方法、年平均发生率法、比例系数法和史料考证。讨论华南沿海地震带历史地震的可靠性和与现代仪器记录资料统一使用的问题,确定合适的b,进而较好的估计代表地震活动水平的年平均发生率ν,为地震危险性分析提供可靠的地震带活动性参数

  • 标签: B值 ν值
  • 简介:ResearchonnonlinearR/SmethodanditspplicationinearthquakepredictionBi-QuanWANG(王碧泉);Han-MingHUANG(黄汉明);Hong-ShunFAN(范洪顺);Chuen...

  • 标签: NONLINEAR theory FRACTAL DIMENSION EARTHQUAKE PREDICTION
  • 简介:本文讨论可信的历史地震资料和现代化仪器记录资料的统一使用问题。

  • 标签: 历史地震 检验 b值统计
  • 简介:Ingeneral,earthquakecyclerelatedtoearthquakefaultingcouldincludefourmajorprocesseswhichcouldbedescribedby(1)faultlocking,(2)self-accelerationornucleation(possibleforeshocks),(3)coseismicslip,and(4)post-stressrelaxationandafterslip.Asuddenstaticstresschange/perturbationinthesurroundingcrustcanadvance/delaythefaultinstabilityorfailuretimeandmodifyearthquakerates.Basedonasimpleone-dimensionalspring-sliderblockmodelwiththecombinationofrate-and-statedependentfrictionrelation,inthisstudy,wehaveapproximatelyderivedthesimpleanalyticalsolutionsofclockadvance/delayoffaultfailurescausedbyasuddenstaticCoulombstresschangeappliedinthedifferenttemporalevolutionperiodsduringanearthquakefaulting.Theresultshavebeenusedinthephysics-basedexplanationofdelayedcharacteristicearthquakeinParkfieldregion,California,inwhichthenextcharacteristicearthquakeofM6.0after1966occurredin2004insteadofaround1988accordingtoitscharacteristicreturnperiodof22years.Atthesametime,theanalyticalsolutionsalsoindicatethatthetimeadvance/delayinCoulombstresschangederivedbythedislocationmodelhasacertainlimitationandfundamentalflaw.Furthermore,wediscussedtheessentialdifferencebetweenrate-andstate-variableconstitutive(RS)modelandCoulombstressmodelusedcommonlyincurrentearthquaketriggeringstudy,anddemonstratedthat,infact,theCoulombstressmodelcouldbeinvolvedintheR–Smodel.Theresults,wehaveobtainedinthisstudy,couldbeusedinthedevelopmentoftime-dependentfaultinteractionmodelandtheprobabilitycalculationrelatedtothetime-dependentandrenewalearthquakepredictionmodel.

  • 标签: 时间变化 故障锁定 RS 静应力 地震断层 时间依赖性
  • 简介:Basedonisotropiclinearporoelastictheoryandundertheundrainedcondition,wesummarizethreeequationsconnectingtheSkempton’scoefficientBwiththegroundwaterlevel.Afteranalysis,weproposeamethodtocalculatetheSkempton’scoefficientBaccordingtotherelationshipbetweenwaterlevelandtidalstrain.WiththismethodwecangetthevalueofBwithouttheearthquakeoccurrence,whichcanprovidethehighfrequencywavesforresearch.Besides,wecanalsogetthein-suitSkempton’scoefficientBwithouttheexperimentofrockphysics.Inaddition,weanalyzetheobserveddataofChangpingstationrecordedingroundwatermonitoringnetwork(abv.,GMN)beforeandaftertheWenchuanMS8.0withthismethod,andfindoutthere’saslightchangeofthevalueofBaftertheseismicwavespassedby,whichimpliesthatthepropagationofseismicwavesmayhavebroughtsomevariationstotheporoelasticmediumofthewell.

  • 标签: 地下水状况 观测站 基础 岩石物理实验 地震波 排水条件
  • 简介:本文通过对华北地区和西南地区完整地震目录按照均匀抽取和非均匀抽取2种原则进行抽取地震,得到了地震目录遗漏率和b变化量间的经验关系式。结果表明,在进行非均匀抽取地震时,得到的地震目录遗漏率和b的减小量间呈正比关系;在进行均匀抽取地震时,利用最小二乘法和极大似然法计算得到的b变化较复杂,b随地震目录遗漏率的增加,或为增加,或为减少。同时,在进行非均匀抽取地震时,地震目录遗漏率对极大似然法计算的b影响大于最小二乘法计算的b影响。

  • 标签: 完整性 B值 遗漏率
  • 简介:本文引进了震级——频度关系的b谱的概念,给出了计算b谱的矩方法,对我国华北和西北地区分别计算和分析了以半年为单位的不同时段M_L≥3.0地震的b谱线。所得结果表明,在研究区内发生6级左右以上大震前半年至一年半之内,b谱的形态要出现较明显的前兆异常变化,因而可在地震预报中加以应用。

  • 标签: b值谱 矩方法 形态异常 地震预报
  • 简介:b是研究地震活动的重要指标,其广泛应用于地震危险性分析和地震预测研究之中,与实际资料的完整性、样本量的大小、计算方法等因素有着重要的关系。常见的b计算方法有最小二乘法和最大似然法,样本量的大小对这2种方法影响很大。本文利用蒙特卡罗模拟地震目录和汾渭地震带实际目录作为样本,从中抽取不同大小的样本量进行计算,研究不同样本量下这2种方法计算得到的b与设定或真实之间的差别。结果表明,最小二乘法需要的最低样本量为1000,最大似然法为200;当样本量达不到要求时,计算出的b是不可靠的;由于对样本量的要求不同,前者适用于计算区域的整体b,而后者在研究某区域b在时间轴上的变化方面更有优势。本研究为确定2种b计算方法对样本量的最低要求提供了参考依据。

  • 标签: B值 最小二乘法 最大似然法 样本量大小
  • 简介:Inthispaper,basedonGansuDigitalSeismicNetworkdatasince1990,wecalculatedb-valueand⊿b-valueoftheneighborhoodareabeforethe2013Minxian-ZhangxianM_S6.6,earthquake.Theresultsshowthattheearthquakeoccurredatthemarginofthesignificantlylowerb-valueareainsoutheastofGansuandbeforetheearthquaketheneighborhoodareahadanobviouslyabnormal⊿b-value.Fromtheearthquakeandthespatialdistributionoflowb-value,theregionstillhasthepossibilityofgeneratingdangerousstrongearthquakes.

  • 标签: 数字地震台网 甘肃东南部 b值 异常 岷县 地震发生
  • 简介:Rèsumèonnewmonograph“AdvanceinMathematicalSeismology”edit┐edbyJunjiKoyama&FengDeyiThenewmonograph“AdvanceinMathematicalSeismo...

  • 标签:
  • 简介:  Introduction  Withrapiddevelopmentandadvancementofeconomyandsociety,lotsofcitygroupsorcitybeltswithex-tra-largecitiesastheircentershavebeenformedinChina.Theregionsthesecitygroupslieinusuallyhavewell-developedeconomy,densepopulation,andareregionalpoliticsandculturecenters.Somegroupslieintheregionswithhighlevelofearthquakeactivity,suchastheSurroundingCapitalCityGroupwiththecentersofBei-jingandTianjin.Oncealargeearthquakeoccurs,itsinfluencewillspreadtoveryextensiveregionanditsdisasterwillbetremendoustoo.Soearthquakeresistanceanddisastermitigationofcitygroupwillbeverysignificantissue.Thecitiesinagrouphaveclosedistancewitheachother;theycancarryoutunifiedpreparationfordisasterasonewholeandreducetheheavyloadofsinglecitybeforeanearthquake,andhaveanadvantageofpromptmutual-aidafteranearthquakebecauseofclosedistance.Itisespeciallysignificanttomitigatetheloseoflives.Oneimportantpreconditionisthatallthecitiesinonegroupcannotbeexposedtothesamelevelofdestroyduringoneearth-quake.Sothedivisionofcitygroupintheregionwithdensecitiesdistributionshallbeverysignificanttotheemergentmutual-aidinearlytimeafteralargeearthquake.Forthisgoal,thecharacteristicsandcorrelativityofearthquake′simpactoncitiesinonegroupneedtoclearlybeconsidered.Thecitieswithsimilarfeaturesandstrongcorrelativityofhistoricalearthquakeinfluencehavelargechancetosuffersameleveldestroyduringthefuturestrongearthquakeandaredisadvantagetoprovidemutual-aidandshallnotbedividedintoonegroup.  ……

  • 标签: city group EARTHQUAKE IMPACT AFFECTED intensity
  • 简介:TheemergenceofZhangHeng’sseismoscopehasaprofoundhistoricalbackground.ThispaperintendstoexploretheformationandmaterialbasisofZhangHeng’sscientificthought.Itappearsthatthesimpleintentionof"observingvisionsanddistinguishinggoodfortuneormisfortune"washismotivationtodeveloptheseismoscope.Tracingitshistoricalbackground,theauthorsproposedinthispaperthatthedevelopmentofthisseismoscopestartedaround128A.D.,andbasedonperceptualknowledge,twoideasaboutearthquakescameintobeing,i.e.,earthquakelocationcouldbejudgedaccordingtotheinstrumentshakingdirection,andtheearthquakeandearthsplitwereessentiallydifferent.Intheinstrumentmanufacture,ZhangHengadvocatedaprincipleof"makingutensilstoimitatecosmos".Bythisprinciple,thefollowingthreeproblemswerereadilysolved:theseismoscopeimitatedtheresponseofthesuspensionsystemtoearthquakes(i.e.naturalseismoscope).Technically,thetriggermechanismofthelatchwasusedforreference,anditrecordedthephysicalevidenceofearthquakeoccurrencebyaningeniouswayofaballdroppingfromadragon’smouth.Thesolutionofthesethreekeyproblemsleadtotheemergenceoftheseismoscopein132A.D.andthesuccessfuldetectionofanearthquakein134A.D.Hisinventiondeepenedhumanity’sknowledgeofnaturallaws,andpromotedthedevelopmentofscienceandtechnologyinthattimeandlater.

  • 标签: 候风地动仪 张衡 地震定位 科学思想 仪器制造 物质基础
  • 简介:In2004,China’sdigitalseismicobservationnetworkprojectbegantodeploy40setsYRY-4four-componentboreholestrainmetersinordertomonitorearthquakepreparationprocess.Thepaperdescribesobservedsolidtidalstraindiscretenessandtidalfactoranisotropy,analyzesthereliabilityofobservationaldataanddiscussesthecauseforthisphenomenon.Aftergettingridofinterferences,thenetwork,intwoyearspractice,hasobservedseveralpre-seismicstrainanomaliesatstationsclosetoepicentersespeciallyintheWenchuanMS8.0megaquake.Itshowsthatthisboreholestrainmeternetworkiscapableofmonitoringseismogenicprocess.

  • 标签: 应变网络 分量式 孔容 中国 地震孕育过程 观测网络
  • 简介:ThestudiesonthestructureandphysicalpropertiesoftheEarth'sinteriordonebyChinesegeophysicistsfrom1999to2002werereviewedinthispaper.Itincludesseveralresearchareas:thestructureoftheEarth'sinteriorsusingseismictomography,anisotropyoftheuppermantleinChinaanditsadjacentareas,qualityfactorQβforSwaves,subductionzone,mantlediscontinuities,physicalpropertiesofEarth'smaterialsandothers.Thereviewconcernsmainlythecontents,themethodsandtheresultsofthestudies.ItcanbeseenthatnewprogressinthestudyonthestructureandphysicalpropertiesoftheEarth'sinteriorhasbeenmadeinthelast4yearsinChina.Itisshownonthreeaspects:advancementmadeonsomepreexistentareas;pioneeringonsomenewfieldsandnewmethodsadopted.

  • 标签: 地球内部构造 物理性质 地震学 各向异性 断层
  • 简介:ThebvaluespectrumandηvaluebythemomentmethodToruOuchi(大内)DepartmentofEarthSciences,FacultyofScience,KobeUniversity,Kobe,657,...

  • 标签: b VALUE SPECTRUM MOMENT METHOD η
  • 简介:基于Sato单次散射模型,利用2007年3月13日福建数字地震台网记录的发生在福建省北部地区的45条ML≥2.0级地震波形资料,对福建北部地区尾波Q进行了研究,研究中首先计算各条记录尾波4—18Hz间15个频率的尾波Q,并对Q与频率之间的依赖关系进行拟和,拟和结果为:Qc(f)=(150.34±42.51)f^(0.8214±0.2109)。

  • 标签: 尾波Q值 SATO模型 福建北部
  • 简介:过去常在在当前的地震代码采用的基于力量的设计过程决定力量减小因素的最重要的参数是结构的韧性。为在一个灵活基础上支持的结构,韧性因素能被基础依从影响。在当前的代码给的韧性因素主要被分配忽略这研究的目的是在像栈的结构的韧性因素上估计SSI现象的意义的SSI并且因此的效果。像栈的结构的使变形的配置就非线性的时刻弯曲关系而言作为横梁元素的一个集合被理想化,当一个线性摇摇摆的模型被实现为支持的土壤建模时。用一套人工的记录,重复了线性、非线性的分析被逐渐地在非线性的分析增加加速的紧张到首先在线性、非线性的分析钢让步被观察的水平和相应于栈倒塌的水平执行。无弹性、有弹性的电阻之间的差别以排水量韧性因素被确定了。结果显示基础灵活性能减少系统的韧性并且忽视这现象可以在灵活地支持的R/C像栈的结构的地震表演的预言导致错误的结论。

  • 标签: 延展性 结构 基础 堆栈 活性 非线性分析
  • 简介:CalculationofbvalueanditsapplicationinearthquakepredictionHua-ChenDUAN(段华琛);Chang-QingFAN(范长青)andYue-MinXU(许跃敏)(Seismological...

  • 标签: b VALUE standardizing time DENSITY FACTOR
  • 简介:多年来的观测分析表明,影响沂水泉氧变化的最大干扰是降雨。由于这种干扰存在着滞后效应,所以用一般相关分析难以将这种影响排除干净。本文采用褶积积分方法较好地排除了降雨对沂水泉氧观测的影响。并用低通滤波方法,探讨了沂水泉氧的长趋势变化。

  • 标签: 褶积积分 低通滤波 沂水泉氧
  • 简介:Thispaperpresentsamodifiedhalf-sine-squaredloadmodelofthejumpingimpulsesforasingleperson.Themodelisbasedonadatabaseof22,921experimentallymeasuredsinglejumpingloadcyclesfrom100testsubjects.Threedimensionalmotioncapturetechnologyinconjunctionwithforceplateswasemployedintheexperimenttorecordjumpingloads.Thevariationrangeandprobabilitydistributionofthecontrollingparametersfortheloadmodelsuchastheimpactfactor,jumpingfrequencyandcontactratio,arediscussedusingtheexperimentaldata.Correlationrelationshipsbetweenthethreeparametersareinvestigated.Thecontactratioandjumpingfrequencyareidentifiedasindependentmodelparameters,andanempiricalfrequency-dependentfunctionisderivedfortheimpactfactor.Thefeasibilityoftheproposedloadmodelisestablishedbycomparingthesimulatedloadcurveswithmeasuredones,andbycomparingtheaccelerationresponsesofasingle-degree-of-freedomsystemtothesimulatedandmeasuredjumpingloads.Theresultsshowthatarealisticindividualjumpingloadcanbegeneratedbytheproposedmethod.Thiscanthenbeusedtoassessthedynamicresponseofassemblystructures.

  • 标签: JUMPING loads three DIMENSIONAL MOTION CAPTURE