起伏地表條件下地震波傳播數值模擬.pdf

1、同濟大學海洋與地球科學學院碩士學位論文起伏地表條件下地震波傳播數值模擬姓名：吳曉豐申請學位級別：碩士專業(yè)：固體地球物理學指導教師：董良國20060201AbstractAbstractSeismicexplorationinhillyareaisaworldwideproblem，inwhichlowS／Nratioandstaticcorrection，deducedtosurfacetopographyarethemostnotor

2、iousproblemsComplextopographygiveschallengetogeophysicistsThisthesisaimstothemodelingofthepropagationofelasticwavesinthepresenceoftopographypresentingtheeffectsoftheirregularsurfaceonthepropagationofthewaves，andgivingath

3、eoreticalguidetoseismicexplorationinhiHyareaThemostdifficultpointforsimulationofsurfacewithtopographyisthefreesurfaceconditionsandthewayofcarryingthemoutThefinitedifference(FD)hasbeenwidelyusedinthesimulationofseismicwav

4、es，especiallyinthesimulationofseismicwavdincomplexmodel，andthefinitedifference(FD)isveiyefficiencyButthemostinfluencedisadvantageisthatitishardforthefinitedifference(FD)todealwiththesurfacewithtopographyHowtousethefinite

5、difference(FD)approachtosimulatetheelasticwavepropagationwithtopographybecomesthebiggestproblemInthispaperalineofpseudo—pointsisaddedabovethetopographytoimplementthefreesurfaceboundaryconditionsAftertheanalysisaboutallki

6、ndsofthesenodes，thewholespaceisdividedto22types，whichhavedifferentfinitedifference(D)schemesByusingthisapproach，finitedifference(FD)methodcanbeusedtosimulatetheelasticwavepropagationinthepresenceoftopographyNumericalmode

7、lingresultsshowthatthetopographycomplicatesthepropagationofseismicwavesinnearsurfaceItleadstotheconversionofdifferentwavessuchassurfacewaveandbodywaveaswellasgenerationofscatteringalongsurfaceThisseverelydeterioratestheS