Benefits of swath mapping for the identification of marine habitats in theNew Caledonia Economic Zone

The ZoNeCo programme is devoted to the evaluation of the marine resources o f the Economic Zone of New Caledonia. The results are essentially dependent on the quality of the seafloor mapping. From 1993 to 1996, four geological and geophysical surveys using the EM12 DUAL multibeam echosounder provided swath-mapping and acoustic imagery data of the seafloor of selected sites on the northern and southern parts of the Norfolk ridge, the Loyalty basin, around the Loyalty islands and in the westernmost part of the Economic Zon e of New Caledonia. The accuracy of these documents shows the morphology of the seafloor in detail and allows rocky substratum to be differentiated fr om muddy bottom. It allows favorable emplacements of future exploratory fis hing surveys to be determined. The benefits of swath mapping are illustrate d by the Halipro 2 deep sea trawling cruise (1996) which used the swath map ping data of ZoNeCo 1 cruise (1993) on the southern prolongation of the New Caledonia mainland and Loyalty Islands. (C) 1999 Ifremer / CNRS / IRD / Ed itions scientifique et medicales Elsevier SAS.