Pollutant concentrations in a sediment core dated by Th-isotopic ratios and the 210Pb dating method

In this research we have dated a sediment core in an estuarine system (southwest of Spain) strongly contaminated by anthropogenic activities, making use of the enhanced levels of some natural radionuclides from uranium series found in the upper layers of the core due to these activities and applying the

The determination of sedimentation rates in Lake Ontario using the 210Pb dating method

The 210Pb dating method has been applied successfully to the determination of recent sedimentation rates at four sites distributed among the three major sedimentary basins (Niagara, Mississauga and Rochester) of Lake Ontario. Following correction for effects due to compaction of the sediments, mean sedimentation rates ranging from 0.02 cm/year at the periphery of the Mississauga basin to 0.11 cm/year in the Niagara and Rochester basins were determined. Allowance for compaction reduced the non-compaction-corrected sedimentation rates by 20–35%. Neither 210Pb nor fallout 137Cs profiles indicated surface mixing of sediment sufficient to noticeably affect the calculated sedimentation rates. At all four sites, the sedimentation rate seems to have remained constant during the last 100–150 years.