简介：ThispaperpresentsactualityofinvestigationandstudyofthecrustalstructurecharactersofEastChinaSeaathomeandabroad.Basedonlotsofinvestigationandstudyachievementsandthedifferenceofthecrustalvelocitystructurefromwesttoeast,theEastChinaSeaisdividedintothreeparts-EastChinaSeashelfzone,OkinawaTroughzoneandRyukyuarc-trenchzone.TheEastChinaSeasheffzonemostlyhasthreevelocitylayers,i.e.,thesedimentblanketlayer(thevelocityis5.8-5.9km/s),thebasementlayer(thevelocityis6.0-6.3km/s),andthelowercrustallayer(thevelocityis6.8-7.6km/s).SotheEastChinaSeashelfzonebelongstothetypicalcontinentalcrust.TheOkinawaTroughzoneislocatedatthetransitionalbeltbetweenthecontinentalcrustandtheoceaniccrust.Itstillhasthestructuralcharactersofthecontinentalcrust,andnoformationoftheoceaniccrust,butthecrustofthecentraltroughhasbecometothinningdown.TheRyukyuarc-trenchzonebelongstothetransitionaltypecrustasawhole,buttheoceansideofthetrenchalreadybelongstotheoceaniccrust.AndthenorthwestPhilippineBasintotheeastoftheRyukyuTrenchabsolutelybelongstothetypicaloceaniccrust.
简介：WhatisacredibleseismicprecursorinobservationofdeformationArealseismicprecursoroughttoberesultedfromthevariationsintheearthstrainandstress.Thedeformationobservationcanprovidetheinformationduringearthquakegestationandoccurrenceperiodforus.Usuallytheseismicprecursorscanbedividedintofieldandepicentralregionprecursors.Theprecursorinformationisveryusefulforseismicpredictionfromepicentralregionornearepicentralregion.Micro-deformationobservationmainlyincludestilt,strainandgravityobservation.ComparedwithGPS,geodesyandmobiledeformationobservation,micro-deformation(tilt,strain)showsthechangeofdeformationwhichiscontinualinalimitedvolumewithdominantobservedrangeof10(6~10(10m.Becausethevariationofthecrustalnatureandcrackingcanbedirectlyobtainedbymicro-deformationobservation,itisaneffectivewaytofindmiddle-shorttermandshort-termprecursor.
简介：Inthispaper,wefirstlyanalyzethe"3,400traveltimetable"usedforalongtimeinXinjiangSeismologicalNetworktoobtainthevelocitystructuremodelsinaccordwiththetablebyfitting.ThenwefitthevelocityofallseismicphasesrecordedinXinjiangregioninJanuary2009~December2013.Simulationanalysisisdoneonthereliabilityandstabilityofthevelocities,andaconceptisproposedforbuildingsubareacrustalvelocitymodelsaccordingtopartitioningofseismicclusterregions.ThecrustalvelocitymodelsuitablefortheYutianareaisfittedwiththedataofallphasesofseismiceventswithinaradiusof1°aroundthe2014YutianM_S7.3earthquakesinceJanuary2009,andthemodelisappliedtotherelocationoftheYutianM_S7.3earthquakeanddeterminationoffocaldepthsoftheearthquakesequence.
简介：TheHimalayan-Tibetanorogenistheyoungestandarguablymostspectacularofallthecontinent-continentcollisionalbeltsontheEarth.Therearenotonlynorth-southextrusionsbutalsoeast-westextensionsintheTibetanPlateau.AllthesephenomenaaretheresultsoftheIndianplatesubductingintotheEurasiaplateabout70Maago
简介：Crustalfaultsusuallyhaveafaultcoreandsurroundingregionsofbrittledamage,formingalow-velocityzone(LVZ)intheimmediatevicinityofthemainslipinterface.TheLVZmayamplifygroundmotion,influencerupturepropagation,andholdimportantinformationofearthquakephysics.Anumberofgeophysicalandgeodeticmethodshavebeendevelopedtoderivehigh-resolutionstructureoftheLVZ.Here,Ireviewafewrecentapproaches,includingambientnoisecross-correlationondenseacross-faultarraysandGPSrecordingsoffault-zonetrappedwaves.Despitethepastefforts,manyquestionsconcerningtheLVZstructureremainunclear,suchasthedepthextentoftheLVZ.High-qualitydatafromlargeranddenserarraysandnewseismicimagingtechniqueusinglargerportionofrecordedwaveforms,whicharecurrentlyunderactivedevelopment,maybeabletobetterresolvetheLVZstructure.Inaddition,effectsofthealongstrikesegmentationandgradationalvelocitychangesacrosstheboundariesbetweentheLVZandthehostrockonrupturepropagationshouldbeinvestigatedbyconductingcomprehensivenumericalexperiments.Furthermore,high-qualityactivesourcessuchasrecentlydevelopedlarge-volumeairgunarraysprovideapowerfultooltocontinuouslymonitortemporalchangesoffault-zoneproperties,andthuscanadvanceourunderstandingoffaultzoneevolution.
简介：ThispaperpresentsthecontemporarymotionandactivedeformationofSouthAmericaplateandrelativemotionofNazca-SouthAmericaplateusingspacegeodeticdata.TheSouthAmericaplateismovingataverage14.5mm/awithanazimuthof15.2°andshrinkinginthewest-eastat10.9mm/a.ThegeodeticdeformationsofsiteswithrespecttotheSouthAmericaplateareinquitegoodagreementwiththeestimateddeformationsfromNNR-NUVEL1A,butthedeformationofthewesternSouthAmericaregionsisverylarge.
简介：TheNorthChinablock,thewesternportionoftheSino-KoreanCraton,isroundedbyYanshanianinthenorthandQinling-Dabieorogenicbeltsinthesouth.Thewidespreaddevelopmentofextensionalbasinsinthisblockindicateshorizontalextensionorcontinuedthinningofapreviouselythickened,trnstablelithospherethroughouttheMesozoic.Inthispaper,weattempttosimulatenumericallythegeodynamicalprocessofthebasinformationbyusingthemountain-basinevolutionsystem.WeassumethattheformationofnumeroussedimentarybasinsintheNorthChinablockistheresultofthecrustalextension,whichdestructsrapidlythepreviouslythickenedcrust.
简介：Thispaperusesmulti-quadricequationsinterpolationtoes-tablishawidelycoveredandvaluablespeedfieldmodelofChina,withwhichthehorizontalcrustalmovementpatternsareobtained.Thepresent-dayverticalcrustalmovementvelocityim-ageofChinaisalsoexpressedbyGPSobservations,fromwhichwecanknowtheverticalcrustalmovementpatterns.
简介：Thispaperselectstherecordsof7,412earthquakes,eachrecordedbymorethan10stationsinYunnanbetween2009and2014toacquirethetraveltimecurves.Meanwhile,forimprovingprecision,linearanalysis,reducedtraveltimecurveandintervalstabilityanalysisareconductedfocusingontherecordsof83earthquakeswithML≥3.0recordedeachby≥80%ofthestations,andbycombiningpredecessors??researchresults,theinitialcrustalvelocitymodelofthestudyareaisobtained.Byselecting200earthquakeswithM≥3.0occurringinYunnanbetween2010and2014,usingtheHyposatbatchlocationprocessingmethodtoiteratetheinitialvelocitymodel,andperformingfittingtoSwaveslayeredvelocitystructure,weobtainthecrustalvelocitymodelfortheYunnanregion,namely,the2015Yunnanmodel,with:vP1=6.01km/s,vP2=6.60km/s,vPn=7.89km/s,H1=20km,H2=21km,vS1=3.52km/s,vS2=3.86km/s,vSn=4.43km/s.AnalysisonearthquakerelocationsbasedonthenewmodelshowsthatmostearthquakesoccurringinYunnanareatadepthof10km-20kmoftheuppercrust.TheMarch10,2011MS5.8YingjiangandAugust3,2014MS6.5Ludianearthquakesarerelocated,andthefocaldepthsdeterminedwiththenewmodelarerespectivelyclosetotheprecisepositioningresultandhypocentraldistancetothestrongmotionstationsattheepicenters,indicatingthatthenewone-dimensionalvelocitymodelcanbetterreflecttheaveragevelocitystructureofthestudyarea.
简介：Asynthesisofcrustalthicknessestimateswasmaderecentlyutilizingavailablefield,geochemical,seismicity,shearwavevelocityandgravitydatainthePhilippines.TheresultsshowthatasignificantportionofthePhilippinearchipelagoisgenerallycharacterizedbycrustwithathicknessofaround25to30kilometers.However,twozones,whicharemadeupofathickercrust(from30to65km)havealsobeendelineated.TheLuzonCentralCordilleraregionischaracterizedbythickcrust.AnotherbeltofthickenedcrustisobservedintheBicol-Negros-Panay-CentralMindanaoregion.ThispaperexaminestheinterplayoftectonicandmagmaticprocessesandtheirroleinmodifyingPhilippinearccrust.Theprocesses,whichcouldaccountfortheobservedcrustalthicknesses,arepresented.Thecontributionsofmagmaticarcsascomparedtothecontributionoftheemplacementandaccretionofophiolitecomplexestocrustalthicknessarealsodiscussed.
简介：TheGlobalPositioningSystem(GPS)isanewmethodtomonitorthecrustaldeformationforearthquakeprediction.Nowafour-dimensionalcrustaldeformationmonitoringnetworkapplyingGPStechniqueshasbeenestablishedinNorthChina,whichisanimportantseismicmonitoringarea.Resultswithhighprecisionhavebeenachievedinthefirstmeasurementsinceaseriesofadvancedmethodsandmeasureswereadopted,andthusagoodfoundationhasbeenlaidforfutureresearchesonearthquakepredictionandgeodynamics.
简介：WesimulateGPShorizontalvelocityfieldintermsofrotationsofcrustalblockstodescribedeformationbehavioroftheChinesemainlandanditsneighboringareas.31crustalblocksareboundedprimarilyby~30Quaternaryfaultswithdistinctgeometriesandvariablelong-termratesof<20mm/a,and1683GPSvelocitiesweredeterminedfromdecade-longobservationsmostlywithanaverageduncertaintyof1?2mm/a.WedefineGPSvelocityatasitebythecombinationofmotionofrigidblockandelasticstraininducedbythefaultthatislockingduringaseismiccycle.ModelvelocitiespredictedfromthepreferableblockmodelmatchwellwiththeGPSvelocitiestoanuncertaintyof~1.7mm/a.Theslipratesinferredfromthismodelisinarangeof6?18mm/aforthemajorfaultsinTibetanditsmarginsand1?4mm/aineasternChina,consistentwithgeologicalobservations.Ournumericalsimulationsuggeststhatthecrustalblocksdeforminternallyatalevelof~10×10-9/a,quitesmallincomparisonwithsignificantdeformationlocalizedalongfaultzonesof50?100kmwide.Weconcludethatthepatternofcontinentaldeformationisnotcontinuous-likebutblock-like,andthetenetofplatetectonicsmaybeapplicabletocharacterizetheactivedeformationinAsia.
简介：ShanxiGrabenisinthemiddlepartoftheNorthChinaCraton,fromsouthtonorth.WiththeteleseismicdatarecordedbyRegionalSeismographNetworksandthetemporaryZBnet-WSeismicArrayaroundeastpartofShanxiGraben,wemeasuredthecrustalthicknessandvP/vSratiobeneatheachstationusingtheH-jstackofreceiverfunctions.Theobservedcrustalthicknessshowsobviouslateralvariation,increasinggraduallyfromeasttowestintheShanxiGraben.BeneaththeShanxiGrabenthecrustisrelativelythickerthanbothsidesofthesouthandthenorth.Inaddition,thevP/vSratiointhenorthofstudyzoneishigherthanthatinthesouth.ThehighestvP/vSratioexistsinthecrustoftheXindingbasinandtheDatongbasin.Ourstudyalsosuggeststhathighvelocityratiomightresultfromthestrongactivitiesofthemagmationandvolcanism.
简介：ThispaperdiscussestheseismicactivityinBeijingMunicipalityanditsadjacentareas(whicharereferredtoastheBeijingregioninthepaper).Byusingfuzzymathematics,thefactorscontrollingregionalcrustalstabilityaretransformedintofuzzyinformationandthenamodeloffuzzydiagnosisisestablished.AfuzzycomprehensiveevaluationofregionalcrustalstabilityintheBeijingregionismadeaccordingtotheseismicandgeologicalconditionsoftheregion.
简介：ＲｅｓｅａｒｃｈｏｆｐａｔｔｅｒｎｄｙｎａｍｉｃｓｐａｒａｍｅｔｅｒｓｏｆｃｒｕｓｔａｌｄｅｆｏｒｍａｔｉｏｎｆｉｅｌｄｉｎｓｅｉｓｍｏｇｅｎｉｃｐｒｏｃｅｓｓＳｈｕｏ－ＹｕＺＨＯＵ（周硕愚），ＹｕｎＷＵ（吴云），Ｒｕｏ－ＢｏＷＡＮＧ（王若柏）ａｎｄ...
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