Dispersion characteristics of Scholte waves on horizontal layered seabed
Scholte waves propagate along the seafloor fluid-solid interface and exhibit typical dispersion charac-teristics.The dispersion properties of Scholte waves can be utilized for the inversion of the shear wave velocity of the shallow seabed,making it an effective tool for seabed shear wave velocity modeling.It is of critical im-portance to establish the theoretical model of Scholte wave dispersion.In this study,a horizontal layered model of seawater-seabed elasticity is developed based on a real seawater-seabed environment.The dispersion equa-tion and displacement equation for Scholte waves in this model are derived using the continuity conditions of boundary stress and displacement.The influence of seawater depth and seabed property parameters on the dis-persion characteristics of Scholte waves is analyzed.Experimental results using a 6-layer seawater-seabed model show that:①Regardless of the seabed is hard or soft,Scholte waves exhibit distinct dispersion charac-teristics.In the case of a hard seabed,the energy of Scholte waves is mainly concentrated in the seawater,with the fundamental mode having the weakest energy and the second mode having the strongest energy.As the sea-water depth increases,the dispersion characteristics of Scholte waves weaken.For the soft seabed model,the energy of Scholte waves on the solid seabed significantly increases,and the seawater depth has little effect on Scholte wave dispersion characteristics.②Compared with deep-water environments,Scholte waves have stron-ger energy and more pronounced dispersion characteristics in shallow water.Therefore,utilizing Scholte waves for inverting the shallow seabed shear wave velocity in shallow water environments yields higher accuracy and reliability.Finally,based on an actual seabed elastic geological model of a working area in the East China Sea,multi-component seismic data are simulated,and dispersion curves are extracted.A comparison analysis be-tween the theoretically calculated dispersion curves and the extracted dispersion curves shows a good agree-ment,confirming the accuracy of our theoretical approach.
Scholte wavehorizontal and layered seabeddispersion characteristicsamplitude-depth distributionshear wave velocity
万方数据
维普
