Figure 11 Activity concentrations of 137Cs (Bq kg-1 dw) in sectioned (0-1, 1-3 and 3-6 cm) sediment cores from stations HEI07, HEI08, HEI42 and HEI47. Average depths of each section are plotted. Activity concentrations in HEI47 were below detection limits in all samples. Detection limits are shown as open symbols. Analytical uncertainties are given as ±2σ .