Our primary goal is to further develop, implement, apply, and validate theory and schemes for a prototype Wide Area Ocean Floor Mapping system. Our specific objectives are to: (i) Characterize and predict underwater sound propagation uncertainty/distributions due to inexact bathymetry fields and ocean environmental and seabed uncertainties, and (ii) assimilate limited acoustic and oceanographic data for the joint principled Bayesian inversion of environmental and acoustical fields, and for the corresponding rigorous estimation of bathymetry.