Wind effect on suspended sediment distribution, Bahía Blanca Estuary, Argentina.

PIERINI, J.O.; PICCOLO, M.C.; PERILLO, G.M.E.

Mar del Plata

Congreso; 2001. IAPSO -IABO Meeting. The 2001 Ocean Odyssey; 2001

IAPSO-IABO

Distribution of suspended sediment on the middle reach of the Canal Principal of the Bahía Blanca Estuary, Argentina where made as part of a project to analyse an injection dredge operating at Puerto Galván Harbor. Measurements were made using an ADCP (600 kHz) in five defined transects (3 in the Canal Principal and 2 at dock sites) along a complete tidal cycle. Data form the acoustical backscattering of the ADCP were employed for studying the temporal and spatial distribution of the suspended sediment. The ADCP was calibrated against OBS vertical profile severy time a circuit of all 5 transects was made (a total of 10 circuits were made). Simultaneous wind data (velocity and direction) were obtained from an automatic weather station located within 1 km of the study site. Wind direction changed from NW to SW at about 3 hours after the initiation of the study and to the SE coincident with the last circuit. Changes in wind speed for the period with SW direction were remarkable. As a result of these changes in direction and velocity, Suspended sediment distribution and the influence of wave erosion on the surrounding tidal flats are very well defined and clearly show the displacement of the sediment due to wind influence. Changes in wind speed are also reflected in the sediment distribution.