The results of a detailed magnetostratigraphic and biostratigraphic study of late Pliocene to early Pleistocene marine marl sequences from the Monte Singa and Crotone areas in Calabria, Italy are presented.The magnetostratigraphy from the Monte Singa sequence ranges from below the Gauss/Matuyama boundary up to and including the lower Olduvai boundary. Normal polarities at a level corresponding to isotope stage 81 most probably represent the R~union subchron. From the lower Olduvai boundary upward, a reliable magnetostratigraphy could not be established due to increased weathering of the marls, resulting in mainly secondary magnetizations.The magnetostratigraphy from the composite sequence of the Crotone area belongs to a large part of the Matuyama Chron and includes the Olduvai subchron. The position of the lower and upper boundaries of the Olduvai subzone could be established more precisely than from earlier results. Moreover, the upper boundary of the Olduvai subzone poses an ambiguity: a relatively long normal polarity interval representing the main Olduvai subchron and corresponding to a duration of 115 ka is followed by a short (30 ka) reversed subchron and the short (15 ka) normal Vrica subchron. Another option, and more in accordance with the duration of the Olduvai subchron in literature, would be to consider the complete N-R-N polarity succession with a total duration of 160 ka as representing the Olduvai subchron, implying that this Olduvai subchron has a short reversed interval in its upper part.Linear interpolation and extrapolation yield ages for the most important late Pliocene-early Pleistocene biostratigraphic datum levels. An age of 1.69 Ma is found for the Pliocene-Pleistocene boundary, using the conventional polarity time scale dated with radiometric results. However Hilgen [1], in correlating the sapropel groups and patterns to the precession curve of the Earth's orbit, obtained significantly different ages for the polarity transitions of the present study. According to this astronomically calibrated polarity time scale, the age of the Pliocene-Pleistocene boundary is 1.81 Ma.

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A well‐dated, high‐resolution record of climatic change is presented for the late Pliocene Mediterranean. Principal component analysis on abundances of 14 planktonic foraminiferal species reveals a series of late Gauss to early Matuyama surface water cooling events which can be correlated with North Atlantic glacial isotope stages 108 to 94. The abundance record of the benthic foraminifer Trifarina angulosa suggests lowered bottom water temperatures at times of surface water cooling. The record of surface water oxygen and carbon isotopes shows an inverse pattern with δ18O maxima and δ13C minima at times of cool sea surface temperature conditions. Concomitant decrease in P/B value and increased admixtures of clastic material suggest that late Gauss to early Matuyama surface water cooling events in the Mediterranean are accompanied with glacioeustatic sea level low‐stands. Major surface water cooling events are associated with invasions of Neogloboquadrina atlantica. This North Atlantic mid‐ to high‐latitude species is at 2.55 Ma close to the Gibraltar portal whereafter it could invade the Mediterranean repeatedly during periods of climatic cooling until it disappears from all over the North Atlantic and Mediterranean at the end of glacial stage 96.

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A high-resolution magnetoblostratlgraphy is presented for the early Late Phocene m Sicily Paleomagnetm measurements on samples from 100 stratlgraphm levels provide an unprecedented high-quality polamty sequence whmh extends from the upper reversed Gilbert to the upper normal Gauss subchron. The resultant chronology for the early Late Phocene provides ages for the following principal Mediterranean bloevents: (1) FOD Globorotaha crassaformls at 3.40 Ma, (2) prolonged absence of Globorotaha punct~culata between 3.38 and 3 16 Ma, (3) LOD Uwgerma rutda at 3 16 Ma, (4) LOD Sphaero~dmellops~s semmuhna at 3.07 Ma, (5) LOD Globoquadrma altzsp~ra at 3 04 Ma and (6) LOD C~blc~des ~tahcus at 2.96 Ma.Summer and winter surface water temperature estimates for the period 3 50 to 2 92 Ma are based on the abundances of Glob~germo~des saccuhfer and Globorotaha punctwulata m 111 samples with an average resolutmn of some 5000 years Short-term varmtmns m temperature of the surface water and m colour and carbonate content of the sediment are primarily controlled by the equmoxal precession A higher seasonahty during deposltmn of the grey-coloured, carbonate-poor facms suggests that at that time the summer solstice occurred near penhehon, whereas an reverse ahgnment occurred at the time of deposltmn of whlte-coloured, carbonate-inch layers Thin phase-relatmnshlp between the precessmn cycle and grey-coloured layers is also vahd for the sapropels whmh began to intercalate m the grey-coloured layers at 2 94 Ma Long-term changes m surface water temperatures include a warmmg between 3 38 and 3 18 Ma followed by a coohng from 3 18 to 3 03 Ma. The warming of Mediterranean surface waters at 3 38 Ma is beheved to be assocmted w~th the final closure of the Isthmus of Panama. Consequent strengthening of the Gulf Stream rejected larger volumes of warm surface water into the North Atlantm Drift and eastern boundary current and thin caused surface water temperatures m the mid to high-latitude northeast Atlantic and Mediterranean to rose. The subsequent chmatm coohng at 3 18 Ma is hnked to a first stage of Northern Hemmphere continental me growth.