Dennis A. Lindwall
Joseph F. Gettrust
Naval Res. Lab. Detachment, Code 362, Stennis Space Center, MS 39529-5004
The spectral response versus grazing angle of the seafloor sediment for several kilometers of deep towed, multichannel seismic reflection data from Atlantic seafloor near the Blake outer ridge shows variations of as much as 15 to 20 dB in bottom loss over distances of less than 50 m. A video of this spectrum versus offset (SVO) data, which explicitly shows the lateral variations as the DTAGS instrument is towed along just above the seafloor, is presented. A few regions of anomalously high shear wave velocities also are identified in these observations. These data demonstrate that a seemingly smooth seafloor can be a rough, frequency-dependent scattering surface. [This work is supported by the Office of Naval Technology.]