Numerical simulation of acoustic wave field of seafloor sediments based on Biot model

Based on the Biot model, Acoustic wave field of seafloor sediments are calculated and analyzed by means of finite-difference numerical simulation. According to the results, Porosity(Ø) and permeability(К) both have important influence on wave field of marine sediment. As Ø increases, velocity and amplitude of the fast wave decrease, but velocity of the slow wave increases. As К decreases, the amplitude of the slow wave decreases. In addition to reflection and transmission characteristics, the transform features of wave appear on the interface of two sedimentary layers of marine sediments. On the interface, the fast wave is transformed into the shear and the slow wave. The shear wave is transformed into the fast wave. The slow wave is transformed into the shear and the fast wave. Extraordinarily, the fast wave which transformed from the slow wave has identical properties with the usual fast wave such as a little velocity dispersion and attenuation.