| Summary: | International audience Palynology contributes for long to stratigraphy, based on presence-absence of plant taxa (i.e., families,genera or species), a method severely thwarted by longitudinal and mainly latitudinal-altitudinal distributionof plants.Following pollen analysis applied to late Quaternary deposits, so successful not only for climatereconstructions but also for short-to long-distance stratigraphic correlations, we developed a similar approachfor the whole Cenozoic thanks to actual botanical identification of pollen grains based on their complete andrigorous morphological examination. Usually, identifications are provided at the genus level considering thatmost of the modern genera existed since the early Paleocene.The age of each studied exposed or drilled section is first determined using worldwide biostratigraphicmarkers (planktonic foraminifers, calcareous nannofossils, dinoflagellate cysts for marine sediments;micromammals for lacustrine deposits) and paleomagnetism. Then, pollen countings allow establishingdiagrams in which pollen percentages and/or ratios express the climate evolution and match with referenceoxygen isotopic curves. In such a frame, it is possible to identify similar and parallel climatic changes that maybe reliably correlated. Illustrative examples are shown from the European and Mediterranean Pliocene andMiocene and from Paleocene and Eocene from the Arctic Ocean, i.e. from the icehouse and greenhouse worlds,respectively.Finally, this Russian doll-like process, with biostratigraphic datation followed by climatostratigraphiccorrelations, may result in the astronomical deciphering of the most favourable sections. Such stratigraphicstudies were supported by Total since 1970.
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