Radiocarbon convention ages were calibrated using marine mode of programme Calib5.1 (Stuiver and Reimer, 1993; Stuiver et al., 1998). Cores LC-21, LC-31, SL-31, SLA-9, C-40, and SK-1 datings include a local DR correction of 149 ± 39 years (Facorellis et al., 1998) in the sapropel and a DR of 58 ± 85 years (Reimer and McCormac, 2002) outside of the sapropel; see text for further discussion. Dates in LC-21 are after Mercone et al. (2000), and dates in C-40 are after Geraga et al. (2000). Sedimentation rates are determined from the known radiocarbon dates in each core, and a mean sedimentation rate is used in each core. Sample uncertainty is calculated as the sum of the uncertainties in sample range and in possible bioturbation range (see text). Total uncertainties include the sampling uncertainty, the stated AMS machine errors, and the uncertainty in the correlation framework used to transpose these dates into the stacked time frame. Calibrated age range is given as the 2 sigma range after (Stuiver and Reimer, 1993; Stuiver et al., 1998), and the median probability age is also given (Stuiver and Reimer, 1993; Stuiver et al., 1998).