Acoustic observations of suspended participate matter in the ocean
CLOUDS of suspended particulate matter in the ocean have been observed by satellite1, sensed by nephelometers2, and sampled by water bottles. We present here evidence that it may be possible to observe oceanic suspended particulate matter acoustically. The particulate matter discussed is thought to have arisen from a dredging operation. It is also thought that the suspended matter is present at lower concentrations than any in any other case recorded acoustically3. Certain questions, as yet unresolved, regarding acoustic scattering strengths are also discussed.
Study of fine material in suspension in the estuary of the Loire and its dynamic grading
Abstract The tidal and seasonal movements of the turbidity maximum and the fluid mud layer of the Loire estuary were investigated and related to the concentrations of different clay minerals. The concentrations of Illite and Montmorillonite are shown to be inversely related, while Montmorillonite reaches a maximum concentration, approximately 40% of clay minerals present, in the zone between the turbidity maximum and the fluid mud. Seasonal variations show that the concentration of Montmorillonite moves with the turbidity maximum.
Les minéraux argileux dans l'estuaire de la Gironde
L'etude de la repartition des mineraux argileux dans les depots recents de l'estuaire de la Gironde ainsi que dans les cours inferieurs de la Garonne et de la Dordogne permet de mettre en evidence d'une part, l'origine continentale des vases sedimentees dans l'estuaire de la Gironde et d'autre part, l'important role de transport joue par les courants de maree qui remontent le cours inferieur de la Dordogne.