Grain size data of sediment samples from the Kvarken Archipelago, eastern Gulf of Bothnia, impacted by metal loading from acid sulphate soils

This dataset includes grain size distribution, determined for 1-cm sediment slices of 5 short gravity-cores from the Kvarken Archipelago, eastern Gulf of Bothnia, northern Baltic Sea. Geochronology of the cores is constrained by the measurements of Cs-137 activity content. The sediments represent organic-rich brackish-water muds.