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Bay Akrotiri section represents a thick terrigenous sequence laying along the southern part of Paliki peninsula (southwest Cefallinia). The data of the calcareous nannofossil quantitative analysis indicate that the studied sediments are ranging in terms of age between 1.95 Ma and 1.238 Ma approximately. The provided distribution patterns clearly depict an apparent evolutionary lineage close to the Plio/Pleistocene boundary, from small Gephyrocapsa placoliths to larger forms of gephyrocapsids.

Spanochorion composite section (NE Lefkas) and Aghios Vassilios section (W Lefkas) have been studied semiquantitatively for their calcareous nannofossil content. The calcareous nannofossil biostratigraphy, performed at the Paxos unit atypical flysch sediments of Aghios Vassilios section, permits their biostratigraphic correlation with the uppermost part of NN4 biozone and the lower part of NN5 biozones (Martini, 1971) or MNN4b and MNN5a (Fornaciari and Rio, 1996), which chronostratigraphically point to Early Langhian age and range between 15.974 and 14.53 Ma. Τhe most interesting biostratigraphic result is the detection of the Sphenolithus heteromorphus Paracme End at the base of Aghios Vassilios section, a biohorizon that marks the basal Langhian deposits in the Mediterranean region. The mollasic sediments of Spanochorion section are more or less of the same age, ranging between 15.5 and 14.53 Ma. The biostratigraphic results of the present study reinforce the hypothesis that the molassic sediments of NE Lefkas Island behind the Ionian thrust were isochronously deposited with Paxos atypical flysch sequences deposited in front of Ionian thrust, at least until Early Langhian times.

Detailed quantitative analyses of coccolithophores performed on the shallow deposits of the southeastern Aegean region (core NS-14, 505 m depth), evidenced that the distribution of calcare-ous nannoplankton assemblages during the last 13 ka BP reflects paleoenvironmental changes which are directly related to parameters such as temperature, salinity, productivity and nutrient flux in the water column. Analysis enabled the separation of the assemblages in four groups. Group A consists of Emiliania huxleyi and the subtropical species Syracosphaera spp. and Rhabdosphaera clavigera, Group B is composed of Helicospaera spp. and Florisphaera profunda, typical species for high productivity conditions in the middle-lower photic zone, Group C consists of Gephyrocapsa oceanica and Braarudosphaera bigelowii, that characterise low salinity conditions and Group D includes Umbilicosphaera spp. and Calcidiscus spp. which are described as relatively eutrophic species. The Holocene assemblages differ distinctly from the living coccolithophore communities in the coastal ecosystems of the Aegean Sea, where only Group A coccolithophores are thriving in the seasonally controlled marine environment.

Στα πλαίσια της παρούσας εργασίας πραγματοποιήθηκε δειγματοληψία από το κατώτερο τμήμα των Σχιστολίθων της Βίγλας, από την τομή Φρύγανο {νήσος Ιθάκη). Η ανάλυση με βάση τα ασβεστολιθικά ναννοαπολιθώματα επιτρέπει τον βιοστρωματογραφικό συσχετισμό της βάσης των Σχιστολίθων της Βίγλας στη w τομή Φρύγανο, με το ανώτερο τμήμα των βιοζωνών BC21 (Bown et al., 1998) και NC7 (Roth, 1978), που χρονοστρωματογραφικά συσχετίζονται με το Ανώτερο Απτιο. Η πιστοποίηση της ηλικίας της βάσης των Σχιστολίθων της Βίγλας στη νήσο Ιθάκη (εξωτερικό περιθώριο της Ιονίου λεκάνης) ως Ανώτερο Απτιο, ενισχύει την υπόθεση ότι η απόθεση των Σχιστολίθων της Βίγλας είναι ισόχρονη., The calcareous nannofossil biostratigraphy, performed at the basal part of the Vigla Shale Member (Frygano section, Ithakl Island), permits its biostratigraphic correlation with the uppermost part of BC21 biozone (Bown et al., 1998) and the upper part of NC7 biozone (Roth, 1978), which chronostratigraphically point to Late Aptian. This result reinforces the hypothesis that the deposition of Vigla Shales is isochronous in the Ionian zone.