Stable oxygen isotope data from four holes drilled at the Ocean Drilling Program Site 967, which is located on the lower northern slope of the Eratosthenes Seamount, provide a continuous record of Eastern Mediterranean surface-water conditions during the last 3.2 Ma. A high-resolution stratigraphy for the Pliocene-Pleistocene sequence was established by using a combination of astronomical calibration of sedimentary cycles, nannofossil stratigraphy, and stable oxygen isotope fluctuations. Sapropels and color cycles are present throughout the last 3.2 Ma at Site 967, and their ages, as determined by calibration against the precessional component of the astronomical record, are consistent with those estimated for the sapropels of the classical land-based marine sequences of the Punta Piccola, San Nicola, Singa, and Vrica sections (southern Italy). The Site 967 oxygen isotope record shows large amplitude fluctuations mainly caused by variations in surface water salinity throughout the entire period. Spectral analysis shows that fluctuations in the δ 18O record were predominantly influenced by orbital obliquity and precessional forcing from 3.2 to 1 Ma, and all main orbital frequencies characterize the δ 18 O record for the last million years. The start of sapropel formation at 3.2 Ma indicates a possible link between sapropel formation and the build up of northern hemisphere ice sheets. The dominance of the obliquity cycle in the interval from 3.2−1 Ma further points to the sensitivity of Eastern Mediterranean climate to the fluctuations in the volume of Arctic ice sheets. An intensification of negative isotope anomalies at Site 967, relative to the open ocean, supports a link between high run-off (during warm periods) and sapropel formation. freshwater input would have inhibited deep-water formation, which led to stagnation of deeper waters. Comparison with the land sections also confirms that differential preservation and diagenesis play a key role in sapropel occurrence.

High‐resolution micropaleontological (planktonic foraminifera and calcareous nannofossils) and geochemical (stable isotopes, organic carbon, Fe, P, S, Ca, Ba, Mn, and Al) records are presented for the first sapropel‐containing carbonate cycle in the Pliocene of Sicily. The carbonate cycle is characterized by a gray to white to beige to white color layering typical of the marls of the Trubi formation. A faintly laminated sapropel is intercalated in the gray‐colored bed of the carbonate cycle. CaCO3 content varies from 40% in the beige to 45‐50% in the white layers. Lowest CaCO3 content of 25–30% is found in the gray layer and sapropel. Variations in carbonate and organic matter percentages can best be explained by changes in paleoproductivity rather than by variations in dilution and dissolution. Total productivity was highest during deposition of the gray layer and sapropel, as indicated by high organic carbon and Ba contents and high abundance of Globorotalia puncticulata. Carbonate production reached its highest values, however, during deposition of the white layers, as evidenced by enhanced abundances of planktonic foraminifera and nannofossils. The low carbonate content in the gray layer and sapropel is explained in terms of a collapse in carbonate production caused by extreme changes in the physical and biochemical properties of the water column, which in turn resulted in siliceous plankton and opportunistic foraminifers such as Globorotalia puncticulata outcompeting most calcareous organisms. The beige layer represents a low‐productivity environment similar to the present‐day eastern Mediterranean basin. Several mechanisms have previously been proposed to explain variations in productivity in the eastern Mediterranean. Both sapropels and gray layers were deposited at times when perihelion occurred in northern hemisphere summer. We envisage that the increase in seasonal contrast resulting from this orbital configuration enhanced winter mixing and stabilization of the water column during summer, both leading to favorable conditions for intensification of the spring bloom. In addition, a decrease in excess evaporation, as can be deduced from the δ18O record, led to shoaling of the pycnocline and reduced circulation, thus enhancing the availability of nutrients in the photic zone. Finally, enhanced precipitation and associated runoff should have caused an increase in river‐borne nutrients.

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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.