Metals in shelf sediments and their association with continental discharges in a tropical zone

Geochemical studies of shelf sediments of the south-eastern Gulf of Mexico were carried out to understand the influence of fluvial and fluvio-lagoonal discharges on sediment geochemistry and to study elemental distribution pa tterns that could be used together with hydrographic and sedimentological d ata to assess depth circulation. On the basis of sediment chemical composit ion, three provinces were identified: fluvial, fluvio-lagoonal and calcareo us; their distribution is a function of circulation patterns and fluvio and fluvio-lagoonal discharges. Factor analysis separated the sediments into t hree groups: fluvial influence, anthropic activities and fluvio-lagoonal or igin.