简介：Inthisstudy,wepresentanewmethodtocomputeinternalco-seismicdeformationsofahomogeneoussphere,basedonourpreviousapproach(Dongetal.2016).Inpracticalnumericalcomputations,weconsiderastrike-slippointsourceasanexample,andcomputetheverticalco-seismicdisplacementondifferentinternalsphericalsurfaces(includingtheEarthsurface).Numericalresultsshowthattheinternalco-seismicdeformationsaregenerallylargerthanthatontheEarthsurface;especially,themaximumco-seismicdisplacementappearsaroundtheseismicsource.Theco-seismicdisplacementsareoppositeinsignfortheareasoverandbeneaththepositionoftheseismicsource.Theresultsalsoindicatethatthecurvatureeffectoftheinternaldeformationisprettylarge,andlargerthanthatontheEarthsurface.Theresultsindicatethatthedislocationtheoryforasphereisnecessaryincomputinginternalco-seismicdeformations.

简介：Inthisstudy,weanalyzetheco-seismicresponseofwaterlevelsintheJiajiwelltostrongearthquakes(MS≥7.8)from2001to2010atanepicentraldistancelessthan8000km.Weinvestigatedtheco-seismicvariationformofwaterlevels,andanalyzedtherelationshipbetweentheamplitudeofwaterlevelvariationandthemagnitudeandtheepicentraldistance.Wethencheckedtheseismicwavephaseswhenthechangesofwaterleveloccurred.Itwasshownthat:(1)thewaterlevel'sco-seismicresponseismainlycharacterizedbyescalationwithnooscillation;(2)theamplitudeofwaterlevelchangehasacertainconnectionwithepicentraldistanceandmagnitude;(3)co-seismicresponseofwaterlevelsintheJiajiwellshowsacertaindirectivity;(4)mostoftheco-seismicresponseswerecausedbysurfacewaves,andsomebylong-periodSwaves.

简介：Inthispaper,statisticsaretakenontheco-seismicresponseofundergroundfluidinYunnantotheNepalM_S8.1earthquake,andtheco-seismicresponsecharacteristicsofthewaterlevelandwatertemperatureareanalyzedandsummarizedwiththedigitaldata.TheresultsshowthattheNepalM_S8.1earthquakehadgreaterimpactontheYunnanregion,andthemacroandmicrodynamicsoffluidsshowedsignificantco-seismicresponse.Theearthquakerecordingcapacityofwaterlevelandtemperaturemeasurementissignificantlyhigherthanthatofwaterradonandwaterqualitytothislargeearthquake;themaximumamplitudeanddurationofco-seismicresponseofwaterlevelandwatertemperaturevarygreatlyindifferentwells.Thechangingformsaredominatedbyfluctuationandstepriseinwaterlevel,andarisingorfallingrestorationinwatertemperature.Fromtherecordsofthemainshockandthemaximumstrongaftershock,wecanseethatthegreatermagnitudeofearthquake,thehigherratiooftheoccurrenceofco-seismicresponse,andinthesamewell,thelargertheresponseamplitude,aswellasthelongertheduration.Theamplitudeanddurationofco-seismicresponserecordedbydifferentinstrumentsinasamewellaredifferent.Watertemperatureco-seismicresponsealmostoccurredinwellswithwaterlevelresponse,indicatingthatthewellwaterlevelandwatertemperaturearecloselyrelatedinco-seismicresponse,andthewellwatertemperatureseismicresponsewascausedmainlybywellwaterlevelseismicresponse.

简介：ThetimeseriesofcoordinatesofalargenumberofGPSstationsintheworld,processedbyProf.GeoffreyBlewittwithGIPSYsoftwareareavailableathttp://geodesy.unr.edu.BasedonthetimeseriesofcoordinatesintheglobalreferenceframeofIGS08atmorethan250stationsofcontinuousGPSobservations,downloadedfromthewebsite,theco-seismicdisplacementsoftheM7.3KyushuearthquakeonApril16,2016inJapanandthepre-seismicstrainaccumulationsanddisplacementsintheregionalreferenceframewereobtained.ThestationofcontinuousGPSobservationatBJFSnearBeijinghasbeenquitestableindisplacementintheeasternpartofChinaformorethan17yearssincethebeginningofitsoperation,andthisstationisusedasthecorestationintheregionalreferenceframeforthepre-seismicdisplacementoftheKyushuearthquakeofM7.3.Themainfeatureofthepre-seismicdisplacementsoftheKyushuearthquakeischaracterizedbylockinginthecrustatandneartheepicenter.Theanomalouspre-seismicstrainaccumulationdevelopedinanareaofanomalousaccumulationoftheshearstraincomponentofγ1onthenortheastsideoftheepicenter,withincreasingsizeoftheareaandincreasingmagnitudeinγ1.Thelargestareacoveredbytheanomalousγ1isabout2000km2.ThechangeintheEcomponentatBJFSsinceNovember26,2015wascausedbythereplacementofthereceiverandtheantennaatthestation.Inordertostudytheshort-termchangeindisplacementsatstationsatandneartheepicenter,thetimeseriesat3stationswithcontinuousGPSobservations,2atSUWNandDAEJinsouthKoreaand1atBJSHnearBeijingwereanalyzed.Theanalysisshowsthatthedisplacementsatthe3stationshavebeenquitestableinthesamemannerineastAsia.Thus,BJSHisusedasthecorestationintheregionalreferenceframeofdisplacementandthedisplacementtimeseriesshowthattherewerenosignificantshorttermanomaliesbeforetheearthquake

简介：Basedontheelasticdislocationtheory,multilayeredcrustalmodel,andrupturemodelobtainedbyseismicwaveforminversion,wecalculatedthecoandpost-seismicsurfacedeformationandgravitychangescausedbytheYushuMW6.9earthquakeoccurredonApril14,2010.TheobservedGPSvelocityfieldandgravityfieldinYushuareasaredisturbedbythecoandpost-seismiceffectsinducedbyYushuearthquake,thusthetheoreticalcoandpost-seismicdeformationandgravitychangeswillprovideimportantmodificationforthebackgroundtectonicmovementofYushuandsurroundingregions.ThetimerelaxationresultsshowthattheinfluencesofYushuearthquakeonYushuandsurroundingareaswilllastaslongas30to50years.Themaximumhorizontaldisplacement,verticalupliftandsettlementareabout1.96,0.27and0.16m,respectively,themaximalpositiveandnegativevalueofgravitychangesare8.892×10-7m·s-2and-4.861×10-7m·s-2,respectively.Significantspatialvariationscanbefoundonthecoandpost-seismiceffects:Theco-seismiceffectmainlyconcentratesintheregionneartherupturefault,whileviscoelasticrelaxationmostlyactsonthefarfield.Therefore,whenusingthegeodeticdatatoresearchtectonicmotion,weshouldnotonlyconsidertheeffectofco-seismiccausedbyearthquake,butalsopayattentiontotheeffectofviscoelasticrelaxation.

简介：铅合金减震器是一种适用于电瓷型电气设备的新型减震器,其动力特性对减震效果有重要影响。根据断路器等电气设备的特点,定制了相应的铅合金减震器。通过铅合金减震器滞回特性试验,研究了加载频率对其动力特性的影响。同时以不同加载频率下得到的骨架曲线作为材料的本构关系,研究了加载频率对单自由度体系弹塑性地震反应的影响。研究表明：在相同输入下,采用不同本构关系的单自由度体系,其相对位移峰值、永久位移及塑性耗能均有较大差异,应重视加载频率对铅合金减震器动力特性的影响。

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