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

PIERINI, JORGE O; PICCOLO, M CINTIA; PERILLO, GERARDO M. E.

Mar del Plata

Congreso; Joint IAPSO-IABO Assemblies, 2001: An Ocean Odyssey; 2001

IAPSO-IABO

Distribution of suspended sediment on the middle reach of the Canal Principal of the Bahía BlancaEstuary, Argentina where made as part of a project to analyse an injection dredge operating at PuertoGalván Harbor. Measurements were made using an ADCP (600 kHz) in five defined transects (3 inthe Canal Principal and 2 at dock sites) along a complete tidal cycle. Data form the acousticalbackscattering of the ADCP were employed for studying the temporal and spatial distribution of thesuspended sediment. The ADCP was calibrated against OBS vertical profile severy time a circuit ofall 5 transects was made (a total of 10 circuits were made). Simultaneous wind data (velocity anddirection) 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 theSE coincident with the last circuit. Changes in wind speed for the period with SW direction wereremarkable. As a result of these changes in direction and velocity, Suspended sediment distributionand the influence of wave erosion on the surrounding tidal flats are very well defined and clearlyshow the displacement of the sediment due to wind influence. Changes in wind speed are alsoreflected in the sediment distribution.