Chronological records of metal deposition in sediments from the Strait of Sicily, central Mediterranean: Assessing natural fluxes and anthropogenic alteration

Sediment box-cores were recovered from the Strait of Sicily along two onshore–offshore transects in waterdepths of 29–500 m. Samples were dated by 210Pb and analysed for major and trace elements. Inspections ofchronological profiles integrated with application of statistical algorithms to the geochemical dataset andsupported by in situ hydrological observations were used to assess factors driving element distributions.Mineralogical and chemical variability of sediments offshore of the southwestern Sicily coast reflect the irregularsea floor morphology of the Adventure Bank. Anthropogenic inputs explain enrichments with respect tobackground values for Sb, As, Pb, and Hg, that become more marked since approximately the 1960s. Clearfluctuations of major and trace element concentrations along a+150 year record and high background values ofsome trace metals (notably Cr, Ni, and locally As) are interpreted as signals of geothermal and/or magmaticactivities in the Strait of Sicily. A combined effect of current flowing, sea floor morphology and thermohalinegradient appears to encourage trace metal accumulation in front of the southern coast of Sicily.