This project will develop parallel algorithms for the description of problems in wave propagation. A series of models based on the two-dimensional wave equation will be considered. These are: i) the simplest representation of wave motion, as described by the acoustic wave equation ii) wave propagation described by the homogeneous formulation of the spatial displacements, and iii) the corresponding heterogeneous formulation for spatial displacement. Geometrically complex subsurface models can be investigated by the latter formulation. In each case parallel algorithms based on finite difference approximations will be implemented. The artificial boundaries to the physical domain can be replaced by a damping boundary layer or numerically absorbing boundaries. The accuracy and efficiency of the algorithms will be compared with their serial counterparts. Additionally, the pseudospectral method, which may be supposed to have greater accuracy, will be implemented for each of these models. Its accuracy and efficiency will be compared with the finite difference solutions.