Chemical and mineralogical characterization of the sediments from the Mira, Ilhavo and Ovar channels of Aveiro Lagoon (Portugal)

The paleoenvironmental reconstruction of Aveiro Lagoon is being carried out based on the sedimentological, paleoecological, geochemical and mineralogical characterization sediment samples collected systematically in lagoon. This paper presents results concerning changes chemical composition fine fraction (<63 µm) clay (<2 from Lagoon, mainly lower intertidal plain subtidal deposits located along Mira, ÿlhavo Ovar channels. A zonography lagoon was established parameters analyzed. show that surface near-surface sediments trap relatively large quantities trace metals, such as Cu, Pb, Co, Ni, Cd, Zn, Fe, Mn Cr, considered to be partially adsorbed, particularly silty clayey particles, coprecipitated Fe oxyhydroxide forms precipitated topmost layers sediments. Series statistically significant relationships were between metal concentrations content semi-quantitatively determined mineral species