In this paper, a method for the extraction of in-water structures (e.g., internal waves) and underwater structures (e.g., vertical transfer of sediments along the water column), observed in Multispectral Infrared and Visible Spectrometer (MIVIS) airborne images is discussed. Images of sea surface structures are captured by a variety of airborne or spaceborne remote sensing instruments, such as photographic cameras, optical scanners, synthetic aperture radars. Investigations on the generation process of these structures and on the local effects are of interest to biological oceanography, to fisheries biology as well as to hydrodynamics. Detection method is based on an interference created among low and mid- high frequencies of water-body images, acquired in spectral bands with different water penetration band characteristics. Features of sea-structures, semi-automatically identified, are mapped in image format.