A critical review and reinterpretation of bio-, litho- and seismostratigraphic data of the Southern Baltic deposits

The aim of this study was the reinterpretation of the published and unpublished Late-Pleistocene and Holocene pollen and diatom diagrams of deposits from the sedimentary basins of the Southern Baltic Sea and the correlation of the distinguished biostratigraphic units with lithological parameters, seismostratigraphic units. Chronostratigraphic subdivision of the Late Pleistocene and Holocene was also made. To facilitate the correlation and reinterpretation of the results of biostratigraphic (palynological and diatom) analyses, new unified and simplified diagrams were drawn using the POLPAL software. Such diagrams were constructed for all the sites under comparison, even for those of no numerical data. In such cases, the published diagrams were scanned and their percentage values were the basis for new diagrams. A review and reinterpretation of biostratigraphic data show an almost complete lack of palynological documentation and diatom diagrams for the Late Pleistocene period and poor documentation for the Early Holocene. Middle and Late Holocene Baltic muds have the best biostratigraphic documentation and radiocarbon dating, which greatly facilitates their location on the geological time scale. Among the Southern Baltic postglacial sediments three lithostratigraphic units were identified. They differ in their lithological features reflecting the conditions prevalent in the sedimentary basin during deposition. It should be noted that these units meet no formal criteria for distinguishing lithostratigraphic units. Similarly, within the Late Pleistocene and Holocene sediments of Southern Baltic deep-water basins, three main seismostratigraphic complexes have been identified. The integrated analysis of seismoacoustic profiles, lithological profiles of cores and reinterpretated biostratigraphic data allow a correlation of the bio-, litho- and seismostratigraphic units with chronostratigraphic units and Baltic evolutionary phases.