《Synthetic sensitivity analysis of high frequency radiation of 2011 Tohoku-Oki （Mw 9.0） earthquake》.pdf

EarthqSci(2014)27(4)：355—364 363 partsbecomesresolvableatgreaterregionsforthereceiver Accordingtoourresult(Fig．6)，hypotheticalstations stationtobe1ocatedat．movingfrom theeastcoasttoward closeto the trench are extremely sensitive to the high thewestcoastontheisland． rfequencyradiatedrfom theup—dipregion．OBS (ocean Spectraofmoderateearthquakesrfom variousdepthsof bottom seismometers)datanearthetrenchhavesignificant the megathrustfaultare usually analyzed to study the advantagesinanalyzingthedepth—varyingruptureprocess． regionaldifferenceofthesourceradiation．(1wakiriand ItcouldbeverifiedbybroadbandOBSdatainthefuture Hoshiba20121analyzethefrequency—dependenttrendof thatwhethertheup—dipregionareacouldgenerateasmuch spectra1ratiofupto20Hz1hasbeenanalyzedto indicate high rfequency (10Hz)radiation asdown—dip region thepossible differentsource timefunctionsofinterplate does earthquakeslocatedrfom theup--dip region todown-d·ip region．However．themainfactorsinaffecting thewave spectra include both regionaldifierence in the source 4 Conclusions radiationandthepatheffects．fe…g 1wakiriandHoshiba 2012、．(Yeeta1．20131useempiricalGreen’sfunction Theresultsofoursynthetictestsindicatethatthepossible (EGF)methodtosuppresspropagationeffects．Thefairly highrfequency (10Hz)energyradiatedfrom theup—dip reliablesourcespectracanonlybeextractedupto5Hzby regioncouldhardlyberesolvedby stationsbecauseofthe carefully dec0nvOluting the EGF eventsbecause ofthe highattenuationofthisregion，whereastheOBSstations clearly increasingnoise levels．In addition，theenergy of located near themegathrustfaultcan detectthe up—dip surfacewavescouldbe much stronger ratherthan body region generating high rfequency radiation．In addition， wavesforshallowereve