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

This dataset includes contents of 55 elements, determined for 1-cm sediment slices of 9 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. The sea area receives large amounts of trace metals (e.g. Al, Cd, Co, Cu, La, Mn, Ni and Zn) from rivers draining the acid sulphate soils of western Finland. The metal contents in the cores increase during the 1960s and 1970s, and stay at the high level afterwards. The enrichment is visible more than 25 km out from the river mouths.