The data for the paleoenvironmental study was obtained on the basis of complex analysis of short sediment cores retrieved in the Arcona, Bornholm, and Gdansk Basins of the Baltic Sea. The cores were collected using a short gravity sediment corer (Niemistö type). The upper layers (0-5 cm) of sediment cores were stained with the 80% ethanol solution of rose Bengal following the protocol (Schönfeld et al., 2012) and were used only for the microfossil analysis. The rests of the cores (below the 5 cm) were continuously sampled with the 1 cm step and were used for the loss on ignition (LOI), microfossil, X-ray fluorescence (XRF), and grain-size analyzes. The grain-size analysis was performed with the laser diffraction particle analyser SALD-2300 (Shimadzu). Prior to the analysis the carbonates were dissolved with the hydrochloric acid and organic matter was dissolved with the hydrogen peroxide, following the method of McCave et al. (1995).