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4 个结果
  • 简介:InthelastdecadeaNewGeophysicshasbeenproposed,wherebythecrustanduppermost~400kmofthemantleoftheEartharesopervadedbyclosely-spacedstress-alignedmicrocracks(intergranularfilmsofhydratedmeltinthemantle)thatinsiturocksvergeonfailurebyfracturing,andhencearecritical-systemsthatimposearangeoffundamentally-newpropertiesonconventionalsub-criticalgeophysics.EnoughofthesenewpropertieshavebeenobservedtoconfirmthatNewGeophysicsisanewunderstandingoffluid/rockdeformationwithimportantimplicationsandapplications.EvidencesupportingNewGeophysicshasbeenpublishedinawidevarietyofpublications.Here,forclarification,wesummariseinonedocumenttheevidencesupportingNewGeophysics.

  • 标签: earthquakes ERUPTIONS MICROCRACKS NEW GEOPHYSICS SHEAR-WAVE
  • 简介:The13November2016KaikouraearthquakeoccurredinthenortheasterncoastalregionoftheSouthIsland,NewZealand.TheMw7.8mainshockgeneratedacomplexpatternofsurfaceruptures,andwasfollowedwithinabout12hoursbythreemoderateshocksofMw≥6.0.HereweuseteleseismicwaveformstoinvertforthesourceruptureoftheKaikouraearthquake.Theresultingslip-distributionmodelexhibitsinsignificantslipnearthehypocenterandthreepocketsofmajorslipzoneswithdistinctsensesofmotion.Themainshockstartedfromarupturenearthehypocenter,grewintothrustonshallowcrustalfaults~50kmnortheastofthehypocenter,andthendevelopedintotwoslipzones:adeeperonewithobliquethrustandashalloweronewithalmostpurelyright-lateralstrike-slip.Locationsofthethrustandstrike-slipmotionsintheslip-distributionmodelagreewellwithreportedcoastalupliftsandhorizontaloffsets.Theoverallslippatternisdominatedbyhorizontalmotion,especiallyatshallowdepth,duetothepartitioningofthrustandstrike-slipmotionsabovethesubductionzonemegathrust.Aftershockdistributionsuggeststhatmostaftershockstendtooccurneartheedgesofthemajorslipzonesofthemainshock.Thisobservationonaftershocklocationsmayprovideusefulinformationforseismichazardassessmentsafterlargeearthquakes.

  • 标签: SLIP DISTRIBUTION Kaikoura EARTHQUAKE AFTERSHOCK DISTRIBUTION
  • 简介:OnNovember13,2016,anMW7.8earthquakestruckKaikourainSouthIslandofNewZealand.Bymeansofback-projectionofarrayrecordings,ASTFs-analysisofglobalseismicrecordings,andjointinversionofglobalseismicdataandco-seismicInSARdata,weinvestigatedcomplexityoftheearthquakesource.Theresultshowsthatthe2016MW7.8Kaikouraearthquakerupturedabout100sunilaterallyfromsouthtonortheast(~N28°–33°E),producingaruptureareaabout160kmlongandabout50kmwideandreleasingscalarmoment1.01×1021Nm.Inparticular,theruptureareaconsistedoftwoslipasperities,withoneclosetotheinitialrupturepointhavingamaximalslipvalue~6.9mwhiletheotherfarawayinthenortheasthavingamaximalslipvalue~9.3m.Thefirstasperityslippedforabout65sandthesecondonestarted40safterthefirstonehadinitiated.Thetwoslippedsimultaneouslyforabout25s.Furthermore,thefirsthadanearlythrustslipwhilethesecondhadboththrustandstrikeslip.Itisinterestingthattherupturevelocitywasnotconstant,andthewholeprocessmaybedividedinto5stagesinwhichthevelocitieswereestimatedtobe1.4km/s,0km/s,2.1km/s,0km/sand1.1km/s,respectively.Thehigh-frequencysourcesdistributednearlyalongtheloweredgeoftherupturearea,thehighfrequencyradiatingmainlyoccurredatlaunchingoftheasperities,anditseemedthatnohigh-frequencyenergywasradiatedwhentherupturingwasgoingtostop.

  • 标签: 2016 MW7.8 Kaikoura EARTHQUAKE BACK-PROJECTION of