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Detailed study of the temporal and spatial patterns of planktonic foraminiferal assemblages was performed on seven eastern Mediterranean deep-sea cores to evaluate differences and similarities in their stratigraphic records during the Eemian sapropel S5 interval. Changes in the succession of planktonic assemblages are very similar in all investigated sapropel S5 sequences. Analyses carried out on the 63 and 150 mu m size fractions indicate that during this time interval, size does not significantly affect the stratigraphic patterns. Benthic assemblages were studied at three sites, where their succession of changes was concordant but locally different. In this framework, comparison of S5 sapropels layers from different areas of the eastern Mediterranean suggests that the onset of the dark colour does not occur in the same stratigraphic position at a regional scale, whereas the absence/drastic reduction of benthic foraminifera within sapropel intervals appears to be a "time equivalent" event and corresponds to the last local occurrence of Globorotalia inflata. (c) 2005 Elsevier B.V. All rights reserved.

Calcareous nannoplankton, diatoms and organic-walled dinoflagellate cysts from seven eastern Mediterranean sediment cores were investigated to clarify the climatic and paleoceanographic conditions that influenced the deposition of sapropel S5 during Marine Isotopic Stage 5e. Warming of surface waters during S5 deposition is indicated by the high abundance of the calcareous nannofossil "small" Gephyrocapsa group, the presence of the dinoflagellate species Spiniferites mirabilis, Spiniferites pachydermus, Lingulodinium machaerophorum and Polysphaeridium zoharyi, and the tropical-subtropical diatom Pseudosolenia calearavis, Chaetoceros resting spores, Rhizosolenids and Thalassionema group. Increased productivity accompanied S5 deposition as evidenced by a general decrease in abundance of calcareous nannofossil superficial species and a coeval increase of dinocysts and diatoms. The productivity increase is further supported by an increase of the deep dwelling calcareous nannofossil species Florisphaera profunda. Stratification of near-surface waters is recorded by the presence of the dinocyst species L. machaerophorum and P zoharyi together with the co-occurrence of the diatom Chaetoceros resting-spore group, Thalassionema frauenfieldii, and Thalassionema nitzschioides var. parva, which reflect transport of neritic waters off-shore, and by the presence of some freshwater and transport-related diatom taxa (Cyclotella, Diatomella and Diploneis). Gradual shoaling of the nutricline and a gradual weakening of water stratification at the end of S5 deposition is indicated by an increase in the deep dwelling calcareous nannoplankton species Gladiolithus flabellatus, which suggests a less-deep niche compared to the deeper dwelling F profunda. Time transgressive variations in the distribution of the calcareous nannofossil Emiliana huxleyi and changes in the abundances of Gephyrocapsa oceanica, small Gephyrocapsa, G. flabellatus, and of the dinocysts R zoharyi and L. machaerophoru

Planktonic foraminiferal and calcareous nannofossil assemblages of three box-cores from the western-central part of the Mediterranean Ridge area were investigated and correlated. In particular we focused on the most significant faunal and floral signals recorded before, during and after sapropel SI deposition. The interval preceding S1 is characterised by an increasing trend of the two planktonic foraminiferal species, Globorotalia inflata and Truncorotalia truncatulinoides, that are usually related to a well developed cold and deep mixed layer. This change is supported also by the rarity of warm water coccolithophorid species and by the presence of the deep dwelling species Florisphaera profunda. The beginning of S1 is marked by the disappearance of G. inflata and T. truncatulinoides and by the significant increase in abundance of Globigerinoides ruber, especially the rosea variety usually considered indicative of warmer conditions. Warm water species increase also within the coccolithophorid assemblage, while the upwelling species Reticulofenestra spp. suddenly decreases and remains low across the whole sapropel interval. The sedimentary expression of the end of anoxia is the upper boundary of the oxidised level observed above S1 in the three box-cores. Across this boundary we detect a small but well defined increase of Braarudosphaera bigelowii, the decrease of warm water coccolithophorid species and the increase of Reticulofenestra spp. This boundary is marked also by the reoccurrence of the planktonic foraminiferal species G. inflata and Neogloboquadrina pachyderma dextral and by an evident decrease of G. ruber var. rosea, indicating the end of the Holocene Climatic Optimum and the beginning of a cold and wet phase, probably corresponding to the Atlantic-Subboreal continental transition. (C) 2002 Elsevier Science B.V. All rights reserved.