Dataset: Outwelling from tidal salt flats adjacent to the Norman River, Gulf of Carpentaria, Queensland


An array of oceanographic instruments was deployed to coincide with the first summer spring high tide inundation of the salt flats adjacent to the Norman River in November 1985. The instruments were deployed at two sites.

Site A was located in the Norman River, where two Interocean Model S4 current meters were suspended in a bottom mounted frame 0.5m and 1.3m above the bottom. A second mooring was deployed, to which an Aanderaa current meter and an Aanderaa water level recorder were attached 1m below the surface. All meters logged data at five minute intervals and each mooring also included an Analite optical fibre nephelometer linked to an Aanderaa data logger, which logged data every 5 minutes.

Site P was located in a narrow tidal creek, which drains into the Norman River and has a watershed comprised of only salt flats. An Aanderaa current meter was mounted on the bottom at this site.

At site A, water samples were collected from 1m above the bottom and 1m below the surface using 5 litre Niskin bottles every 4 hours over two complete tidal cycles (14-17 November). During this time samples were also collected along the creek in which site P was located using 2 litre glass bottles. Near bottom and near surface water samples were also collected from sites ranging from 10km seaward of the mouth of the Norman River to 50km upstream of the river mouth before (13th November) and after (17th November) the tidal inundation.

Water samples were filtered through preweighed 0.4┬Ám Nucleopore polycarbonate membrane filters and stored frozen until analysis for dissolved orthphosphate, nitrate, nitrite and silicate. Separate samples were passed through 25mm diameter GF/F glass fibre filters, which were frozen until analysis for chlorophyll a.

The Aanderaa current meters also recorded temperature and conductivity. In addition temperature, salinity and suspended solids were measured with a CTD probe, which included an optical fibre nephelometer. Vertical profiles were measured along the Norman River on the 13th and 17th of November; at hourly intervals for 48 hours at site A; and every 4 hours along the creek from site P.

General Information