Scattering by an elastic cylinder embedded in a fluid sediment. Generalized method of images (GMI) approach

An original method is presented for calculating the scattered acoustic field due to a plane wave incident upon an infinitely long elastic cylinder embedded in a sedimentary medium. The sedimentary medium is an half space domain bounded by a fluid. The cylinder is parallel to the plane interface between the sedimentary and fluid media.First, in order to estimate the scattering by a cylinder close to a plane interface, an analytical model that generalizes the method of images, restricted to rigid and soft interfaces, is described. The validity and the accuracy of this new approach are analyzed.Under some assumptions, the transmission, from the sediment to the surrounding fluid, of the acoustic field scattered by the embedded cylinder is evaluated, then the detection from the fluid medium of the buried elastic cylinder resonances is treated.