The program in VLF or seismoacoustics (typically 5-30 Hz) is led by Dr. Mercer's collaborator Dr. Robert Odom. They are developing the theoretical basis for producing high fidelity descriptions of VLF acoustic propagation in range-dependent, transversely isotropic heterogeneous fluid-elastic media. For deterministic problems, or when the scattering is moderate, a coupled mode theory is being developed from the first order equations of motion. For cases with strong forward scattering, an elastic energy diffusion equation has been derived that describes the diffusion of energy as a function of range in spectral space. The work is being supported by the Office of Naval Research.
Odom, Robert I. and James A. Mercer, Spectral diffusion of elastic wave energy, Geophys. J. Int.,127, 111-124,1996.
Odom, Robert I., Minkyu Park, James A. Mercer, Robert S. Crosson, and Pauline Paik, Effects of transverse isotropy on modes and mode coupling, J. Acoust. Soc. Am., 100, 2079-2092, 1996.