简介:Epicentral distribution in 1994Pei-ShanCHEN(陈培善)(InstituteofGeophysics,StateSeismologicalBureau,Beijing100081,China)Pei-ShanC...
简介:Slipdistributionofthe1979ImperialValley,1989LomaPrieta,1992Landers,1994Northridge,and1995Kobeearthquakeshowsapiece-wiseGutenberg-Richter'slaw.Forsmallslips,theb-valueisnearto1;whileforlargeslips,theb-valueislargerthan1.
简介:Thisarticlepresentsanapplicationofaproceduretomodifytheintensitydistributionbyassessingthereliability.Therearetwopotentialpossibilitiesthatmayinfluencetheintensitydistribution:(1)Fortheinterpolationerror,wegenerateameasuredgridacrossthecalculationregion.Whenthepointtostationspacingis\5km,weconsidertheresultsprecise;however,somepointshavelessprecisionbecausethesearefartherfromthecorrespondingstations.Whenthespacingisbetween5and50km,weconsidertheresultsimpreciseanddefineareliabilityfactorthatcorrelateswiththedistance.(2)Somerecordsmayhaveerrorsthatresultfromlocalsiteconditions,equipmentproblems,orsomedisturbancesuchaslightningstroke,whichwillleadtosomegridpointshavinganincorrectintensity.Weregresstheattenuationrelationforsiteswithabnormalintensitiesandconsidertheresultstobeaccuratewhenthestandarddeviation(STD)is\randinaccuratewhentheSTDis[2r.WethendefineareliabilityfactortocorrelatewithSTDbetweenrand2r,suchthattheintensitydistributionisinaccordwithbothwavepropagationtheoryandtheinvestigationintensity.
简介:GeographicaldistributionofhypocentraldepthsofChineseearthquakesXING-BEIDUAN(段星北)InstituteofGeophysical,StateSeismologicalBur...
简介:SeveralfactorsareselectedtoreflectthetemporalandspatialfeaturesofseismicityinSouthwestChina.Themeasurementsofthefactorsarealltakenfromthestatisticalrelationbetweenthefactorsandactualearthquakes,andmakethefactorspossessacertainprobabilisticpredictionmeaningandthebaseformutualcontrast.Theeffectsofpredictionofpartofthefactorshavebeenevaluatedandusedtocorrectthefactors.Threesetsofseismicspatialdistributionfunctionshavebeencalculatedbyusingthreedifferentmethodsanddiscussedindetail.
简介:Asoneofthemostimportanturbanlifelinesystems,awaterdistributionsystemcanbedamagedunderastrongearthquake,andthedamagecannoteasilybelocated,especiallyimmediatelyaftertheevent.Thisoftencausestremendousdifficultiestopost-earthquakeemergencyresponseandrecoveryactivities.Thispaperproposesamethodologytolocateseismicdamagetoawaterdistributionsystembymonitoringwatcrheadonlineatsomenodesinthewaterdistributionsystem.Anartificialneuralnetwork-basedinverseanalysismethodisdevelopedtoestimatethewaterheadvariationsatallnodesthatarenotmonitoredbasedonthewaterheadvariationsatthenodesthataremonitored.Themethodologyprovidesaquick,effective,andpracticalwaytolocateseismicdamagetoawaterdistributionsystem.
简介:Inthispaper,thefocusdepthdistributionofearthquakeswitheachmagnitudehasbeenanalyzed.Statisticdatashowthatthelowermagnitudeis,thewiderfocusdepthdistributes.Withlargermagnitude,thefocustendstobeconcentratedinupperormiddlecrustallayers.Weanalyzedthecauseoffocusdepthdistributionandexplainedtheprecursormechanismofsmallandmoderateearthquakeswithoccurringconditionandcharacteristicsofstrongearthquakes.Theresultsofthispapermaybeappliedtodeterminerisksitesofstrongearthquakes.
简介:Byanalyzinghigher-accuracylocationdataoftheTangshanearthquakesequence,acleardistributionpatternofthreeaftershockbeltsintheNE,NWW,andNWdirectionsofhasbeenobtained.TheanalysisrevealsthreeruptureplanesofstrongeventsofMS7.8,MS7.1andMS6.9inthesequence.Itindicatesthatthecomplexpatterniscloselyrelatedtotheearthquakesource,andtheNE-,NWW-andNW-trendingregionalfaultzones,whichhavebeenrevealedbytheresearchofthepre-seismicityanomaly.Insummary,thesourceislocatedinthejunctionofthethreefaultzones,andtheruptureplanesofthethreestrongeventslocatedinthesourcecanberegardedasthelockedsegmentsonthethreefaultzones.Onthesegrounds,thepaperexplainsthecomplexityofthesourceandepicentraldistributionofaftershocks.
简介:Itisproposedthatsomepossiblemacroseismicepicenterscanbedeterminedquicklyfromtherelationshipthatthemicroseismicepicenterslocatedbyinstrumentsbearwithfaults.Basedontheseso-calledmacroseismicepicenters,wecanmakefastseismichazardestimationafterashockbyuseoftheempiricaldistributionmodelofseismicintensity.Incomparisonwiththemethodthatusesthemicroseismicepicentersdirectly,thisapproachcanincreasetheprecisionoffastseismichazardestimation.Statisticalanalysisof133mainearthquakesinChinawasmade.Theresultshowsthatthedeviationdistancebetweenthemicroseismicepicenterandmacroseismicepicenterfallswithintherangeof35kmfor88%earthquakesofthetotalandwithintherangeof35to75kmfortheremainingones.Then,wecantaketheareathathasthemicroseismicepicenterasitscenterandis35kminradiusastheareaforemphaticanalysis,andtaketheareawithin75kmaroundthemicroseismicepicenterastheareaforgeneralanalysis.Therelationbetweenthe66earthquakecasesontheN-SSeismicBeltinChinaandthespatialdistributioncharacteristicsoffaultsandtheresultsoffocalmechanismsolutionwereanalyzedindetail.Weknowfromtheanalysisthattheerrorofinstrumentalepicenterdeterminationisnottheonlyfactorthatgiveseffectstothedeviationofthemacroseismicepicenter.Inadditiontoit,thefaultsize,faultdistribution,faultactivity,faultintersectiontypes,earthquakemagnitude,etc.arealsomainaffectingfactors.Bysortingout,processingandanalyzingtheseaffectingfactors,theprincipleandproceduresforquicklydeterminingthepossiblepositionofthemacroseismicepicenterweresetup.Takingtheseasabasisandestablishinganationwidedatabaseoffaultsthatcontainsrelevantfactors,itispossibletoapplythismethodinpracticalfastestimationofseismichazard.
简介:在2010Yushu地震以后的二个小时,摇晃的紧张分发用基于地点效果的ShakeMap快速的产生系统被获得,由作者发展了,它集成原因的差错的构造设置,罢工和规模的信息,在西方的中国的焦点的机制solutions.fault破裂进程和变细关系,以及本地地点effects.The结果如下:摇紧张分发的主要的轴被指导NW-SE,平行到Yushu差错;meizoseismal区域到达紧张并且盖住300km2;紧张区域主要沿着原因的差错在区域40km东南和震中的15km西北被散布;由于本地土壤条件,有基岩上的紧张的区域的西北的部分看紧张是否从基岩变换成土壤;有紧张的区域,,分别地测量3,000km2,8,000km2,和24,000km2。
简介:AccordingtotierecordsofseismicstationnetworksofChina’scontinentandKoreaPeninsulaandthehistoricaldata,thecompleteseismicitypatternwasobtainedforthefirsttime.Theseismiczoningwasconductedbymeansoftheclusteranalysismethod.Themap’sspatialdistributionofseismicityfrom1960to1994showsthattherearethreestrongseismiczones:thefirstonestrikesintheNEdirection,fromtheJiangsuplaininChinatothecentralKoreanPeninsula;thesecondstrikesintheNWdirection,fromtheBohaiSea,ChinatothesouthernKoreanPeninsula;thethirdstrikesintheNWdirection,fromthewesternLiaoningProvincetoPyongyang.Mostofearthquakesarelocatedalongthesethreezones,theseismicintensityislowerthanthatinthemainland,andexhibitedthefeatureoffracturedcrustofamarginalseabasin.
简介:ThedistributionoftheintensityoftheMojiangMS5.9earthquakeinYunnanProvinceisexpounded,andthedamagecharacteristicsofbuildingsandthedamageratioandseismicdamageindexofvariousbuildingstructuresineachintensityareaarecomparedwiththoseofTheChineseSeismicIntensityScale.Themainbasisandmethodofseismicintensityassessmentarediscussedinthispaper.Itisconcludedthat:①Theseismicintensityshouldbebasedontheearthquakedamageofthehousingstructure,whichtakesupahighratiointheseismicintensityassessment.Itisrecommendedthatseismicintensityisestimatedbycalculatingtheaverageseismicdamageindex.②ThehighestintensityoftheMojiangMS5.9earthquakeisVIIIdegrees,withthelongaxistrendinginthenorth-westdirection.TheareaaboveVIIdegreesis5,180km^2.③TheintensitydistributionoftheMojiangMS5.9earthquakemeetsthenationalstandardandthedistributionlawofseismicintensityinYunnan.
简介:IntroductionThestudiesofseismicsourcephysicsandruptureprocessshowthatthepreparationandgenerationofanearthquakeanditsmagnitudeisrelatedtothegeologicalconditionsandthemediumpropertiesatthesourcetectonicpaFtand,atthesametime,directlytothestrengthofthese...
简介:Basedontheloadmodelofauniformisotropicsemi-infiniteelasticmedium,wededucedacalculationofverticaldisplacementandtiltandproposedamethodofcalculationofverticaldisplacementsandtiltscausedbyirregularloadonthegroundorundergroundatacertainpointwithtwo-dimensionalandthree-dimensionalshapes.Wecomparedthedifferencebetweenthesimplifiedmodelandtheirregularmodel.Finally,theverticaldisplacementsneartheirregularloadandthedistributionofhorizontaltiltarepresented.Theresultsshowthat,comparedwiththepointsimplifiedmodel,theirregularloadmodelhascertainadvantagesfordescribingthenearfield.Theestablishmentofatwodimensionalirregularloadmodelcanhelpwiththecalculationofthemodalvectorsuperpositionafterloadscattering.Thethree-dimensionalirregularloadmodelcanredistributeloadthroughdifferentweightsgiventothescatteredpointsaftertheloadscattering,andthenobtaindisplacementwiththevectorcalculationmethod.Theresultsofvectorsuperpositioncalculationfromthescatteredirregularloadbothintwo-dimensionsandthree-dimensionsareallconvergentobviouslyasgridsbecomedenser,anditisshownthatthecalculationmethodiscorrectandfeasible.
简介:Recentstudiesonassessmentofaverylowannualprobabilityofexceeding(APE)groundmotions,10-4orless,havehighlightedtheimportanceoftheupperboundofgroundmotionswhenverylowprobabilityresultsareacquired.Thetruncationleveladoptedinprobabilisticseismichazardanalysis(PSHA)shouldbedeterminedbyanaleatoryuncertaintymodel(i.e.,distributionmodel)ofgroundmotionsandthepossiblemaximumandminimumgroundmotionvaluesofaspecificearthquake.However,atthepresenttime,itisimpossibletoestablishtheupperboundmodelforgroundmotionsbasedonthesourcecharacteristicsand/orgroundmotionpropagation.McGuiresuggestedatruncationlevelbefixedatanumberof=6,orthedistributionofresidualsbetruncatedinsuchamannerthatsiteintensitycannotbegreaterthantheepicenterintensity.ThisstudyaimstofindareasonableandfeasibletruncationleveltobeusedinPSHAwhenthephysicalmechanismisnotavailabletofindtheextremegroundmotion.AmathematicalanalysisoftheinfluenceofthetruncationlevelonPSHA,casestudiesofsitesindifferentseismotectonicsettings,andadistributionanalysisofgroundmotionresidualsareconductedinthisstudy.Itisconcludedthat=4istheminimumacceptablevalueforengineeringapplicationsforAPEswithin0.002to10-4,andforlowAPEs,suchas10-5and10-6,thevalueofshouldbenolessthan5inmostregionsofChina.
简介:INTRODUCTIONItiscommonknowledgethatthedevelopmentandoccurrenceofanearthquakeisaverycomplicatedgeophysicalprocess.Anearthquakeiscausedbythelocalfailureoftheearthcrustmedium,andearthquakesaredistributedinhomogeneouslyinspace.Seismicactivities,however,arearealreflectionoftheinteractionofthefaults,whichprovidesussomeinformationconcerningtheearthcrustmediumandmayhelpuspredicttheearthquake.Therefore,thestudyoftheseismicitypatterncanbecomeameansofearthquakeprediction.Inordertoreflectdirectlythespacialdistributionofseismicactivities,thesketchofepicentraldistributionhasbeenwidetyusedinthestudy
简介:作为在地震学,液体,热和精力的基本问题,地震附近的分发在地震产生期间采购原料是地震学者的担心的领先的题目。当前,越来越多的研究在地震来源区域附近显示出液体,它在地震准备和产生的过程起一个重要作用。然而,在在深外壳中的液体的来源上有可观的争吵。至于在地震来源区域附近的热的问题,不同模型被建议了向压力热流动解释悖论。在他们之中,动态变弱模型被认为是解决热流动悖论问题的关键。在大地震以后,精力分发是直接与磨擦热有关。立即深实现具有及时、重要的实际意义钻调查在地震产生期间获得液体,磨擦热和精力分发的理解的在里面地点。在液体,热和精力分发研究的最近的国际进步在将为地震准备和出现的理解带重要灵感的这篇论文被考察了。
简介:TheTanlu(Tancheng-Lujiang)faultisoneofthemajorstructuresineasternChina,whichcutsacrossdifferentblocksandcontrolsthetectonicactivity.UsingtheseismicdatafromtheChinaEarthquakeNetworksCenter,weinvestigatethespatialvariationsoftheb-valueintheDabie-Sulu(Jiangsu-Shandong)organicbeltbycalculatingtheb-valueofeachgrid(1°×1°)from1970to2010.Thestudyshowsthat:theb-valueissmallerintheTanlufaultanditsadjacentarea,whichmightsuggestthatthemajorearthquakerecurrenceperiodisrelativelylongduetothelowerfrequencyofsmallearthquakeactivity.InbothsidesofTanlufault,theb-valueishigherattheedgeofSulublockandtheeasternpartofDabieorogenicbelt.ThebvaluesarehigherinNorthChinacentralorogenicbelt,andsmallearthquakeactivitywhichoccurredalongthecentralorogenicbeltisfrequent.Additionally,combinedwithgeologicalandgeophysicalstudy,wefindthattheb-valuehasacertaincorrespondencerelationshipwiththelithologicdistribution,whichinformsusthatseismicactivityfeaturesarecloselyrelatedtotheinhomogeneousmediainthecrust.