The data were acquired with a hull mounted Simrad 30kHz EM300 system (1x1 degree configuration) on Fugro's GeoProspector . Northwest-southeast lines were run approximately parallel to the canyon axis at speeds varying from 6.5 to 8 knots. The beam configuration was controlled to insure a high ping density at all water depths.

The resultant shaded relief bathymetry has been created with a grid spacing of 10m. No interpolation or smoothing has been applied to the data. In the shallower water portions of the field area the grid spacing is 5m.

The furrows in the east-central part of the field area are 20 to 50cm deep and 20 to 50m apart.

These features are smaller than the advertised accuracy of the system and demonstrate the ability to image geologically relevant features with bin sizes significantly smaller than the footprint of individual beams.

Backscatter data show significant variations throughout the field area. Dub-sampled backscatter mosaics of the field area have a pixel size of 1m for all water depths. Backscatter variations appear to be related to changes in seafloor sediment type.

Sub-bottom profiler data were acquired with a hull-mounted GeoAcoustics 4x4 transducer array and a Knudsen 320 topside unit.

Sub-bottom data were acquired concurrently with multibeam data, at multibeam acquisition speeds.

Sub-bottom data show penetrations of up to 50m and clearly image canyon cut and fill sequences, folded strata, and geologically recent faulting.

If 2D seismic data are acquired along with multibeam, Fugro and AOA are able to survey 250sq/km per day, or 100 line km of seismic. If 2D data are not acquired, Fugro and AOA are able to survey more than 800sq/km per day.

MJ Information No: 20039