简介：microearthquakes的高周波的S波浪震动图信封与增加旅行距离，作为向前散布的S波浪信封broadening.Multiple知道的现象和衍射拓宽因为沿着地震光线路径的随机的不同类是S波浪信封拓宽的主要原因，S波浪信封拓宽的现象因此被用来学习S波浪的medium.The山峰延期时间的不同类，它被定义为时间从直接S波浪发作落后到最大值

简介：TheYellowstonevolcanoisoneofthelargestactivevolcanoesintheworld,anditspotentialhazardsdemanddetailedseismologicalandgeodeticstudies.Previousstudieswithtraveltimetomographyandreceiverfunctionshaverevealedalow-velocitylayerinthecrustbeneaththeYellowstonevolcano,suggestingthepresenceofamagmachamberatdepth.Weuseambientseismicnoisefromregionalseismicstationstoretrieveshort-periodsurfacewavesandthenstudytheshallowshearvelocitystructureoftheYellowstoneregionbysurfacewavedispersionanalysis.WefirstobtainedacrustalmodeloftheareaoutsideoftheYellowstonevolcanoandthenconstructedanabsoluteshearwavevelocitystructureincombinationwithreceiverfunctionresultsforthecrustbeneaththeYellowstonevolcano.Thevelocitymodelshowsalow-velocitylayerwithshearvelocityataround1.3km/s,suggestingthatalarge-scalemagmachamberexistsatshallowlevelswithinthecrustoftheYellowstonevolcanicregion.

简介：ＩｎｔｅｒｐｒｅｔａｔｉｏｎｏｆＳｗａｖｅｄａｔａｆｒｏｍＴａｉ′ａｎＸｉｎｚｈｏｕＤＳＳｐｒｏｆｉｌｅａｎｄｉｔｓｒｅｌａｔｉｏｎｓｈｉｐｗｉｔｈＸｉｎｇｔａｉｅａｒｔｈｑｕａｋｅｓＳＯＮＧＹＡＮＳＯＮＧ（宋松岩）１）ＸＵＥＳＯＮＧＺＨＯ...

简介：BasedonSwaverecordsofdeepteleseismsonDigitalSeismicNetworkofShanxiProvince,shearwavevelocitystructuresbeneath6stationswereobtainedbymeansofSwavewaveformfitting.Theresultshowsthatthecrustisthickinthestudiedregion,reaching40kminthicknessunder4stations.Thecrustallalternativeshighvelocitylayerwithlowvelocityone.Thereappearvariedvelocitystructuresfordifferentstations,andthestationsaroundthesametectonicregionexhibitsimilarstructurecharacteristics.Combinedwithdominantdepthdistributionofmanysmall-moderateearthquakes,thecorrelationbetweenseismogeniclayersandcrustalstructuresofhighandlowvelocitylayershasbeendiscussed.

简介：Inthisarticle,weanalyzethecharactersofSV-componentreceiverfunctionofteleseismicbodywavesanditsadvantagesinmappingtheS-wavevelocitystructureofcrustindetail.Similartoradialreceiverfunction,SV-componentreceiverfunctioncanbeobtainedbydirectlydeconvolvingtheP-componentfromtheSV-componentofteleseismicrecordings.OuranalysesindicatethatthechangeofamplitudeofSV-componentreceiverfunctionagainstthechangeofepicentraldistanceislessthanthatofradialreceiverfunction.Moreover,thewaveformofSV-componentreceiverfunctionissimplerthantheradialreceiverfunctionandgivesprominencetothePSconvertedphasesthatarethemostsensitivetotheshearwavevelocitystructureintheinversion.ThesynthetictestsshowthattheconvergenceofSV-componentreceiverfunctioninversionisfasterthanthatoftheradialreceiverfunctioninversion.Asanexample,weinvestigatetheS-wavevelocitystructurebeneathHIAstationbyusingtheSV-componentreceiverfunctioninversionmethod.

简介：EarthquakesofM_S5.6andM_S6.1occurredinYingjiang,YunnanonMay24andMay30,2014respectively.Inthispaper,weusethewaveformdatarecordedbymobileseismicstations(KAC)whichweresetupinthesourceareaaftertheYingjiangMS5.6earthquakeonMay24,2014tostudytheshear-wavesplittingcharacteristicsofYingjiangM_S6.1earthquakesequencewiththeSAMmethod.Theresultshowsthatpredominantpolarizationoffastshear-wavesbeforetheM_S6.1earthquakeisconsistentwiththedirectionofregionalprincipalcompressivestress,andpredominantpolarizationoffastshear-wavesbeforetheM_S6.1earthquakeshowbetterconsistencyandsmallerdispersioncomparedtoaftertheM_S6.1earthquake,andtheremaybeadeflectionforthefastshearwavespredominantpolarizationbetweentheM_S6.1earthquakesequenceandforeshocksequence.Wefoundthatthetime-delaysgenerallyexhibitedalowerlevelbeforetheM_S6.1earthquakeandarelativelyhighervalueaftertheM_S6.1earthquake.

简介：基于管理方程和相等的模型，我们建议在一架飞机之间的关系与放射状地不同类的性质在球状的几何学在一个维的媒介和一个球形的波浪挥动的相等的转变。这些相等的关系能帮助我们在不同类的媒介获得elastodynamic问题的分析答案。介绍相等的转变的物理本质是在几何学和材料性质之间的相等的关系。它显示在球状的几何学的球形的波浪问题能与可变性质域在工具条中被转变成飞机波浪问题，并且它的反的转变也是有效的。在不同类的媒介的波浪运动问题的四个不同例子基于介绍相等的关系被解决。我们在例子获得二张基本分析答案表格我和II，在例子III，和展览调查不同类的一半空间的思考行为在例子IV的一个特殊不同类，它能在经常的振幅把旅行作为球形的波浪。这研究暗示我们的想法成为解决联系问题更容易。

简介：Basedonwaveformdata,severalmethodstodeterminefocalmechanismsofsmallearthquakesweredevelopedsince1980.Kisslinger(1980)andJulian,Foulger(1996)proposedanapproachtodeterminesolutionbyusingamplituderatioofPandSwave.Schwartz(1995)devisedamethodtodeterminesolutionsbytheuseofpolaritydataandamplitudesofseismogramenvelopes.Amplitudesofshortperiodseismicwavespropagatinginaninhomogene-ousmediumaresensitivetothevariationinvelocityandQstructure.Nakamura,etal(1999)tookmediuminhomo-geneityintoaccountindeterminingfocalmechanismsofsmallearthquakesusingwaveformdata.Ifthelocationsofsmallearthquakesareconcentratedinasmallregion,wecanassumethattheraypathsfromtheeventstoagivenstationarealmostthesame.SoPandSwaveattenuationsareindependentofeventlocations.Inthiscaseitiscon-venienttodeterminefocalmechanismsoftheseeventsbyusingshortperiodPandSwavedataj.Focalmechanismsolutionsofsmallearthquakesin5regions,i.e.,Rongchang,Mabian-Muchuan,Ya￠an,BaoxingandMianzhu,whicharecoveredbytheChengduTelemeteredNetwork,areobtainedbyanalyzingthePpolarityandshortbodywaveamplitudedatarecordedinthenetworksince1992.AccordingtothemethodproposedbyGephartandForsyth(1984),basedonwelldeterminedfocalmechanismsolutionsin15sub-zonesofSichuanandYunnanarea,threeprincipalstresstensorss1,s2,ands3,insteadofaveragesofP,B,andTaxisofthesolutions,aredeterminedtorepresenttheregionalstressfielddistribution.

简介：BasedontheseismicobservationreportdataprovidedbytheXinjiangDigitalSeismicNetworkfrom2009to2014,wecalculatethewavevelocityratioanditsbackgroundvalueformediumandsmallearthquakesbyusingthemulti-stationmethodinTianshan,Xinjiang.Thispaperanalyzesthevariationofthewavevelocityratiodisturbancevaluetohighlighttheabnormal,andalsoback-traces7moderateearthquakesattheresearcharea.Theresultsshowthat:(1)thebackgroundvalueofthewavevelocityratioisalmost1.70,thewavevelocityratioobviouslydecreasesinthemiddle-easternpartofTianshanandtheregionnearthePuchangfault;(2)thewavevelocityratiodisturbancevalueismostlylowintheepicenterbeforefourearthquakesofM≥5.0from2011to2013inthestudyarea;(3)before7moderatestrongearthquakes,theearthquakeeventswithlowvalueofthewavevelocityratioaccountforover60%ofcorrespondingtotaleventsneartheepicenters,andthelowvalueofthewavevelocityratioisrelativelyobviousbeforemoderateearthquakes.

简介：Usingthedatasetof20±2secand(A/T)maxofsurfacewavesrecordedbyType-763andType-SKseismographsfromfivestationsinBeijingandelsewhere,themeansquaredeviationsuandrelativemeandeviationsDofMsvaluesdeterminedbyfivecalibrationfunctions(a,a763,a300aNandfromMsz(NEIS)arecomparedandanalyzed.Resultsshowthataanda763arerathergoodbetween20°and160°;anda763arerathergoodbetween10and30for20sec;a300isrelativelygoodbetween160and179.

简介：Inthispaper,ananalyticmethodisdevelopedtoaddresssteadySH-wavescatteringandperformdynamicanalysisofmultiplecircularcavitiesinhalfspace.ThescatteredwavefunctionusedforscatteringofSH-wavesbymultiplecircularcavities,whichautomaticallysatisfiesthestress-freeconditionatthehorizontalsurface,isconstructedbyapplyingthesymmetryoftheSH-wavescatteringandthemethodofmulti-polarcoordinatessystem.Applyingthisscatteredwavefunctionandmethodofmovingcoordinates,theoriginalproblemcanbetransformedtotheproblemofSH-wavescatteringbymultiplecircularcavitiesinthefullspace.Finally,thesolutionoftheproblemcanbereducedtoaseriesofalgebraicequationsandsolvednumericallybytruncatingtheinfinitealgebraicequationstothefiniteones.Numericalexamplesareprovidedforcasewithtwocavitiestoshowtheeffectofwavenumber,andthedistancesbetweenthecentersofthecavitiesandfromthecenterstothegroundsurfaceonthedynamicstressconcentrationaroundthecavityimpactedbyincidentsteadySH-wave.

简介：TwomethodsformeasuringtheattenuationQvalue,frequency-amplituderatiomethodandwaveforminversionmethod,wereanalyzed.Thesizeandshapeofmostrocksamplesinthelaboratorycanhardlyfulfilltherigorousrequirementsoftheabovemethods.AnewtestmethodofusingthewaveenergytocalculatetheQvaluewasproposed.Theprinciple,calculationformulaeandsomepointsforattentionwereexpounded;therelationshipbetweenQ_PandQ_Ewasdiscussed;andmanysamplesweremeasuredbythismethod.Theresultwascomparedwiththosebyothermethods,anditwasconsideredthattheQvaluebythismethodliesbetweenQ_PandQ_E·

简介：一个提起的实验连续地被进行三天，并且速度变化被测量用结尾，波浪interferometry.The测量错误被估计在10-4附近，它在这个时期期间与理论error.The速度变化与一致很好在空气温度直到在速度变化和变化之间的10-3.The关系，气压的压力和稳固的地球潮与线性最不方形的fitting.The被分析速度没在空气温度，而是displa上有依赖

简介：Anew3Dvelocitymodelofthecrustanduppermantleinthesoutheastern(SE)marginoftheTibetanplateauwasobtainedbyjointinversionofbody-andsurface-wavedata.Forthebody-wavedata,weused7190eventsrecordedby102stationsintheSEmarginoftheTibetanplateau.Thesurface-wavedataconsistofRayleighwavephasevelocitydispersioncurvesobtainedfromambientnoisecross-correlationanalysisrecordedbyadensearrayintheSEmarginoftheTibetanplateau.ThejointinversionclearlyimprovesthevSmodelbecauseitisconstrainedbybothdatatypes.Theresultsshowthatataround10kmdepththerearetwolow-velocityanomaliesembeddedwithinthreehigh-velocitybodiesalongtheLongmenshanfaultsystem.Thesehigh-velocitybodiescorrespondwellwiththePrecambrianmassifs,andthetwolocatedtothenortheastof2013MS7.0Lushanearthquakeareassociatedwithhighfaultslipareasduringthe2008Wenchuanearthquake.Theaftershockgapbetween2013Lushanearthquakeand2008Wenchuanearthquakeisassociatedwithlow-velocityanomalies,whichalsoactsasabarrierzoneforrupturesoftwoearthquakes.Generallylargeearthquakes(M≥5)intheregionoccurringfrom2008to2015arelocatedaroundthehigh-velocityzones,indicatingthattheymayactasasperitiesfortheselargeearthquakes.Jointinversionresultsalsoclearlyshowthatthereexistlow-velocityorweakzonesinthemid-lowercrust,whicharenotevenlydistributedbeneaththeSEmarginofTibetanplateau.

简介：

简介：Inordertomakeamoreeffectiveuseofthedatafromregionaldigitalseismographnetworksandtopromotethestudyonshearwavesplittinganditsapplicationtoearthquakestressforecasting,SAMsoftwaresystem,i.e.,thesoftwareonsystematicanalysismethodofshearwavesplittinghasbeendeveloped.Thispaperintroducesthedesignaims,systemstructure,functionandcharacteristicsabouttheSAMsoftwaresystemandshowssomegraphicalinterfacesofdatainputandresultoutput.Lastly,itdiscussespreliminarilythestudyofshearwavesplittinganditsapplicationtoearthquakeforecasting.

简介：ＶａｒｉａｔｉｏｎｓｉｎｓｈｅａｒｗａｖｅｓｐｌｉｔｔｉｎｇｄｕｒｉｎｇａｆｔｅｒｓｈｏｃｋｓｏｆｔｈｅＬｕｑｕａｎｅａｒｔｈｑｕａｋｅｉｎＹｕｎｎａｎＰｒｏｖｉｎｃｅＢＡＩ－ＪＩＬＩ（李白基）（ＳｅｉｓｍｏｌｏｇｉｃａｌＢｕｒｅａｕｏｆＹｕｎｎａｎ...

简介：Theexperimentalstudyofthechangeofwavevelocityinfaultregionsbeforeinstabilityoffrictionalslidingofrockswasconducted.Experimentsshowthatbeforetheinstabilityoffrictionalslidingofrocks,thechangeofwavevelocitycannotbeobservedalonglinesononesideofthefault,buttheprecursorofthedecreaseofwavevelocitycanbeobservedalonglinesacrossthefault.Therefore,whenwetrytopredicttheearthquakesofthestick-sliptypeinfaultregionsbyusingtheanomalyofwavevelocity,themeasuringlinesacrossthefaultsshouldbeselected.

简介：Inordertoinvestigatetherelationbetweenthewatercontentchangingofsurfacesoilandmicro-quakerecordedbeforeearthquakes,wecarriedoutasimulationexperimentinlaboratory.Itspurposeistoexplorewhethertheacousticwavegeneratedbymicro-fracturingbeforeearthquakeareabletochangewatercontentofsurfacesoil,soastounderstandtherelationbetweenthermalanomalyintheremotesensingimagegotfromtheseismogenicareaandthecomingearthquake.Theresultoftheexperimentshowsthatwhentheacousticwaveentersintothesurfacesoilthewatercontenthereincreasesonthebackgroundofdecreasingduetonaturalevaporation.Inthemeantime,temperatureheredecreases.

简介：Experimentsonsonictransmissionshowthataslabstonecandirectlytransmitpartoftheenergyofawaveexcitedbyknockingorbyatransducerintotheair.Theotherpartofthewaveenergycangeneratethenormalmodeofvibrationontheslabstoneandexcitemeasurableacousticsignalsintheair.Thedominantfrequencyisrelatedtothesizeoftheslabstone.Theseresultsindicatethattheacousticemission(AE)inrockalsodisplayssimilarbehaviorifthesourceisshallow.Itisdemonstratedthatwiththenucleationandpropagationofcracks,thedominantfrequencyoftheradiatedwavewillbelower.Whenthefrequencybecomesverylow,thewavecanbetransmittedthroughtherockintotheairandbereceivedbyamicrophone.Accordingtothetheoryofsimilarityofsize,therewillbelow-frequencywavesbeforestrongearthquakesbecauseofnucleationofcracks,whichcanbereceivedbyspeciallow-frequencytransducersorinfrasonicdetectors.Beforeearthquakes,themechanismofprecursorscouldbeverycomplicated.Theymightbeproducedbyplasticcreeporattributedtoliquidsbutnotbrittlefractureinmostcases.Sotheperiodsoftheproducedwaveswillbelonger.Thisperhapsaccountsforthelackofforeshocksbeforemanystrongearthquakes.