摘要
Wepresentsecond-orderexpressionsforthefree-surfaceelevation,velocitypotentialandpressureresultingfromtheinteractionofsurfacewavesinwaterofarbitrarydepth.Whenthesurfacewaveshavenearlyequalfrequenciesandnearlyoppositedirections,asecond-orderpressurecanbefeltallthewaytotheseabottom.Thereareatleasttwoareasofapplications:reflectivestructuresandmicroseisms.Microseismsgeneratedbywaterwavesintheoceanaresmallvibrationsofthegroundresultingfrompressureoscillationsassociatedwiththecouplingofoceansurfacegravitywavesandtheseafloor.Theyarerecordedonland-basedseismicstationsthroughouttheworldandtheyaredividedintoprimaryandsecondarytypes,asafunctionofspectralcontent.Secondarymicroseismsaregeneratedbytheinteractionofsurfacewaveswithnearlyequalfrequenciesandnearlyoppositedirections.Theefficiencyofmicroseismgenerationthusdependsinpartonoceanwavefrequencyanddirection.Basedonthesecond-orderexpressionsforthedynamicpressure,asimpletheoreticalanalysisthatquantifiesthedegreeofnearnessinamplitude,frequency,andincidenceangle,whichmustbereachedtoobservethephenomenon,ispresented.
出版日期
2017年03月13日(中国期刊网平台首次上网日期,不代表论文的发表时间)