Authors: Beaman, R.J.
Publication: FUNGIS News, April: 6-7. Far North GIS Users Group, Cairns, Australia.
The development of multibeam mapping, or swath mapping, has been one of the most significant technological advances in the tools used by marine scientists for the past 15 years. Traditionally, hydrographic surveys were carried out with singlebeam echosounders following a grid of tracks, which can only receive single incidence reflections from the seabed directly beneath the vessel. Missing data was simply interpolated between the tracks. Multibeam systems can now simultaneously collect data using a broad swath of sound with multiple received beams reflected off the seabed. The results of swath mapping are high-resolution digital terrain models (DTMs) of the seabed that are equivalent to aerial or satellite imagery on land.