By presenting sea surface temperatures, planktonic oxygen isotope profiles, and bulk geochemical composition of core sediments, we offer a multiparameter reconstruction of Western Mediterranean oceanography from the Last Glacial Maximum until the Middle Holocene (20,000–5000 cal years B. P.). Sediments from Ocean Drilling Program Site 975 in the Algero‐Balearic basin have been compared with three Alboran basin cores (TTR‐300G, TTR‐302G, and TTR‐304G), all of them investigated at high resolution. This multiproxy approach has allowed two different modes of circulation to be recognized: (1) during the LGM and from ∼8.0 cal. ka B. P. onward, no surface gradient in δ18OG. bulloides is found associated with low productivity, in close analogy to modern conditions; (2) during the Bølling‐Allerød and early Holocene, significant surface isotopic gradients are found with periods probably indicating an unstable water column, associated with enhanced productivity and low bottom oxygen conditions. The close synchrony between the occurrence of the surface isotopic offset and organic rich layer formation implicates that the origin of these features is linked, probably via shoaling of the regional thermohaline circulation. Paleo‐SSTs, derived from planktonic foraminifer assemblages, indicate abrupt changes in surface conditions during the analyzed time interval. Fluctuations in marine productivity based on Ba and total organic carbon are related to water column stability and atmospheric conditions. A sharp warming and δ18OG. bulloides excursion at the end of the Younger Dryas is probably linked to glacial meltwater influence. The riverine input has been reconstructed using the Mg/Al ratio, and Mg/Al peaks during arid periods (Greenland Stadial‐2a and Younger Dryas) related to “bypass” margin processes.

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The Pliocene assemblages of planktonic foraminifers at Sites 975 and 976 were studied quantitatively to obtain data both on the biostratigraphy and on the paleoceanographic conditions prevailing in the western Mediterranean during the Pliocene. Some significant changes in the composition of the assemblages could be used to complement the biochronology of hemipelagic marine sedimentation in the western Mediterranean. Using modern analog techniques, paleoceanographic conditions were assigned to the Pliocene assemblages. The results suggest that during most of the Pliocene the western Mediterranean was characterized by conditions equivalent to those prevailing today in the western Mediterranean and in the North Atlantic, between the parallels of Cape Finisterre and the Canary Islands, although interspersed with episodes both of subpolar and subtropical conditions. In the latest Pliocene, there were frequent subpolar conditions, presaging the entry of polar fauna that marks the beginning of the Pleistocene.

Through the description and interpretation of the position of macro- and microfossils in several sections of the Albian-Cenomanian boundary in SE France and Central Tunisia, a comparison is made between the north and south margins of the Tethyan Ocean by using the occurrences of marker bioevents. For the planktonic foraminifera, the criterions applicable for the accurate determination of Thalmanninella globotruncanoides (Sigal) – the marker species for the base of the Cenomanian stage – are discussed. The species Th. globotruncanoides and the intermediate forms with its ancestor Th. caroni (Ion) are illustrated. For the ammonites, two subjects are new. Firstly, the species Stoliczkaia (Shumarinaia) africana Pervinquiere is illustrated since it is choosen as the indice of the uppermost zone of the Albian (Vraconnian). In northern Africa it replaces Arrhaphoceras (Praeschloenbachia) briacensis (Scholz), the indice for northern Tethys, but restricted to the North European Province. Secondly, specimens of the two genera Graysonites and Utaturiceras – first found in the basal Cenomanian of northern Africa – are described and illustrated.To allow a comparison between north and south Mediterranean sections, respectively Mont Risou and Marcoule for the north and Tunisia for the south, the stratigraphical position of several proxies from planktonic foraminifera, calcareous nannofossils and ammonites are discussed. A widening of the comparison is proposed by taking into account distant regions such as Madagascar and northern California.