Abstract:
Large quantities of carbonate mud are found in suspension, with concentrations reaching 80 mg l(-1), in the lagoon of Mataiva Atoll, French Polynesia. Residence time of water in the lagoon is about 73 days. Carbonate particles are exported offshore in a negatively buoyant plume that sinks in oceanic waters. The carbonate particles are from resuspension of abraded carbonate of biological origin. The negative buoyancy is induced by evaporative cooling of turbid lagoon water, turbidity resulting from wave-driven suspension of calcareous sediment. Contaminated mine water should be released at depth, offshore, as a negatively buoyant plume to sink in oceanic waters.
