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: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