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

Abstract

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 patterns that could be used together with hydrographic and sedimentological data to assess depth circulation. On the basis of sediment chemical composition, three provinces were identified: fluvial, fluvio–lagoonal and calcareous; their distribution is a function of circulation patterns and fluvio and fluvio–lagoonal discharges. Factor analysis separated the sediments into three groups: fluvial influence, anthropic activities and fluvio–lagoonal origin.