Surficial marine deposits in shallow coastal areas and in deep ocean basins are investigated in detail by in situ probe and remote sensing techniques to characterize the geoacoustic and geological properties of surficial sediments. Geosciences research at the Naval Oceanographic and Atmospheric Research Laboratory supports specific naval requirements in mine and Arctic warfare, acoustic bottom and subbottom interaction, coastal engineering, mapping, geoacoustic/geophysical modeling, and antisubmarine warfare. The instrumentation was developed for studies of surficial marine sediments. In situ probes measure ambient and dynamic pore-water pressure, electrical resistivity-conductivity , hydraulic conductivity, and acoustic velocity. Sea-floor mapping of bathymetry and morphology, the determination of sediment types and their physical and mechanical properties, bottom roughness, and subbottom layering are directly related to the Navy’s interest in objects on the sea floor. The development of state-of-the-art instrumentation to measure the acoustic behavior of marine sediments and related properties has been an integral part of the basic research thrust.