[1] Aix Marseille Univ, Univ Toulon, CNRS INSU, IRD,MIO,UM 110, F-13288 Marseille 09, France
[2] Aix Marseille Univ, Univ Toulon, CNRS INSU, IRD,MIO,UM 110, F-83957 La Garde, France
[3] Univ Lille 1 Sci & Technol USTL, UMR 8187, LOG, F-62930 Wimereux, France
[4] CNRS, UMR 8187, LOG, F-62930 Wimereux, France
[5] IFREMER, Ctr Brest, Plouzane, France