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International audience; We evaluate the topographic evolution of the southwestern Alps using Eocene to Pleistocene pollen data combined with existing sedimentological, petrographic and detrital geo-and thermochronological data. We report 32 new pollen analyses from 10 sites completed by an existing dataset of 83 samples from 14 localities situated across the southwestern Alps, including both the pro-and the retro-foreland basins. The presence of microthermic tree pollen (mainly Abies, Picea) indicates that this part of the mountain belt attained elevations over 1900 m as early as the Oligocene. Inferred rapid surface uplift during the mid-Oligocene coincided with a previously documented brief phase of rapid erosional exhumation, when maximum erosion rates may have reached values of up to 1.5–2km/Myr. Slower long-term average exhumation rates of ∼0.3km/Myr since the Late Oligocene helped maintaining the high Alpine topography of the southwestern Alps until today. The relative abundances of meso-microthermic tree pollen (Cathaya, Cedrusand Tsuga) and microthermic tree pollen (Abies, Picea) in the pro-and retro-foreland basin deposits, indicate that the present-day asymmetric topography, with a relatively gentle western flank and steeper eastern flank, was established early in the southwestern Alps, at least since

A pollen record from Puyehue area (40°S; 72°W) in the southern Lake District, Chile, indicates that prior to 13,410 14C yr BP (ca. 16,500-15,200 cal yr BP), cold resistant and hygrophilous vegetation, particularly Nothofagus forest and myricaceous vegetation, covered the area. From ca. 15,000 cal yr BP onward, the forest became increasingly dense. Between 10,010 and 7450 14C yr BP (ca. 11,000-8000 cal yr BP), the expansion of Nothofagus obliqua and the spread of grasses suggests the climate became warmer and semi-arid. Lowland deciduous forest (Nothofagus obliqua, Aextoxicon punctatum, Laurelia sempervirens) and Valdivian rainforest (Nothofagus dombeyi, Eucryphia cordifolia, Caldcluvia paniculata, Aextoxicon punctatum, Laureliopsis philippiana) were abundant. During the next two thousand years, stable warm climatic conditions prevailed, and the diversity of the vegetation increased. From 5760 to 1040 14C yr BP (ca. 6500-900 cal yr BP), the North Patagonian rainforest expanded. The presence of Pilgerodendron/Fitzroya, together with Nothofagus forest, suggests that humid conditions prevailed. During the last millennium, human impact intensified and regional vegetation was disturbed, particularly the lowland deciduous forest and Valdivian rainforest. North-Patagonian and subantartic taxa, such as Podocarpus nubigena, Pilgerodendron/Fitzroya, Nothofagus dombeyi type, Austrocedrus chilensis and Drimys winteri, occupied the low and high-altitude parts of the Cordillera. Five hundred years ago, shrub and grasses expanded in the Nothofagus forest, suggesting that forest became more open under cool-cold, and humid climatic conditions. These conditions prevail to the present day.

International audience; The Cap d'Ailly area (Upper Normandy, France) shows several terrestrial–lagoonal sections recording the negative carbon isotope excursion (CIE) associated with the Paleocene–Eocene Thermal Maximum (PETM; 55.8 Ma). A study of the biomarkers and spore/pollen content of the Vasterival section gave com-plementary information on paleofloral changes that occurred around the Paleocene–Eocene (P–E) bound-ary. Aliphatic hydrocarbon fractions revealed a high abundance of vascular plant biomarkers, including tricyclic diterpanes derived from conifers, fernenes derived from ferns and des-A-triterpenes derived from angiosperms. Whereas the vegetation of the depositional environment surroundings seemed alter-nately dominated by ferns and angiosperms (revealed from biomarkers), the regional flora seemed dom-inated strictly by angiosperms such as Juglandaceae (revealed by pollen). Spore/pollen assemblages revealed no major turnover in the paleovegetation, but slight variation in vegetation composition. How-ever, both biomarkers and spores/pollen exhibited two intervals of rapid floral change: the first occurred around the P–E boundary and the second at the top of the strictly terrestrial unit that coincides with a marine transgression. Comparison of the data with published paleoclimatic results, obtained from the same samples, indicated that the first interval of floral change correlates with strong paleohydrological perturbations, whereas the second is linked to an increasing marine influence.

The Paris Basin represents an historical cradle of Palaeogene stratigraphy, where during the nineteenth century the Palaeocene Series and the “Sparnacian Stage” were established. As highlighted by Aubry et al. (2005), whereas the chronostratigraphic connotation of the “Sparnacian Stage” has been controversial since its definition, modern studies of the late Palaeocene–early Eocene interval have revealed that the so-called “Sparnacian” deposits encompass a remarkable and short (~170 kyr) episode of the Cenozoic, the Palaeocene–Eocene Thermal Maximum (PETM, ~55.8–55.6 Ma). Dinoflagellate assemblages from the “Sparnacian” of the Dieppe–Hampshire and Paris basins do not contain the key species Apectodinium augustum, whereas it is present in the northern Belgian Basin Tienen Formation and is coeval there with the CIE and the Apectodinium acme interval. However, our calibration of the Apectodinium acme to the CIE in the Dieppe–Hampshire and Paris basins suggests its attribution to the A. augustum zone. The absence of species A. augustum in the Anglo–Paris Basin may be explained by its restriction to more offshore conditions.

International audience; The Paleocene-Eocene Thermal Maximum (PETM) is correlated with the first occurrences of earliest modern mammals in the Northern Hemisphere. The latest Paleocene Clarkforkian North American Land Mammal Age, that has yielded rodents and carnivorans, is the only exception to this rule. However, until now no pre-PETM localities have yielded modern mammals in Europe or Asia. We report the first Clarkforkian equivalent Land Mammal Age in the latest Paleocene deposits of the basal Sparnacian facies at Rivecourt, in the north-central part of the Paris Basin. The new terrestrial vertebrate and macroflora assemblages are analyzed through a multidisciplinary study including sedimentologic, stratigraphic, isotopic, and palynological aspects in order to reconstruct the paleoenvironment and to evaluate biochronologic and paleogeographic implications. The mammals are moderately diverse and not abundant, contrary to turtles and champsosaurs. The macroflora is exceptional in preservation and diversity with numerous angiosperms represented by flowers, fruits, seeds and wood preserved as lignite material, revealing an abundance of Arecaceae, Betulaceae, Icacinaceae, Menispermaceae, Vitaceae and probably Cornaceae. Results indicate a Late Paleocene age based on carbon isotope data, palynology and vertebrate occurrences such as the choristoderan Champsosaurus, the arctocyonid Arctocyon, and the plesiadapid Plesiadapis tricuspidens. However, several mammal species compare better with the earliest Eocene. Among these, the particular louisinid Teilhardimys musculus, also recorded from the latest Paleocene of the Spanish Pyrenees, suggests a younger age than the typical MP6 reference level. Nevertheless, the most important aspect of the Rivecourt fauna is the presence of dental remains of a rodent and a ''miacid'' carnivoran, attesting to the presence of two modern mammalian orders in the latest Paleocene of Europe. Interestingly, these two groups are also the only modern groups recorded from the latest Paleocene of North America, making Rivecourt the first direct equivalent to the Clarkforkian Land Mammal Age outside of North America.

Die Florenverbreitung und die Entwicklung des Klimas im Laufe der Zeit bringen interessante Beweise zum Problem der Kontinentalverschiebung. Im Karbon bestand ein einheitlicher Kontinent : die Pangaea. Im Mesozoikum bildeten sich verschiedene Blöcke, die bis zur Mittleren Kreide in ziemlich engem Kontakt standen. Dies bezeugen die weltweite Flora im Jura und im .Wealden sowie die Ausbreitung der Angiospermen über alle Kontinente während der Kreidezeit. Die Öffnung des Atlantischen Ozeans im Paläogen erscheint deutlich, da die europäischen und die nordamerikanischen Floren sich seit dem Eozän in verschiedener Richtung entwickelt haben., Палеоботаника, палеоклиматология и материковыи дрейф Исследования по распределению флоры и эволюции климата на протяжении геологического времени дают интересные аргументы в защиту теории материкового дрейфа. В каменноугольный период существовала единая континентальная масса : земля Пангео. В мезозое эта масса распадается на отдельные блоки остающиеся в тесном контакте вплоть до среднего мела. Доказательством последнего служит космополитизм флоры средней юры и вельда, также как и распространение покрытосемянных на всех континентах в меловом периоде. В палеогене, открытие атлантического океана становится явным, на что указывает различная эволюция европейской и североамериканской флоры., The geographical distribution of past floras and the evolution of climates during geological times bring evidence in support of the hypothesis of continental drift. In the Late Paleozoic began the break up of the primitive universal land mass Pangaea into a northern group of continents (Laurasia) and a southern group (Gondwana). In the first one grew a flora in which Coniferae and Pteridospermae (Alethopteris, Neuropteris...) are dominant ; in the other one grew the Glossopteris flora. During the Mesozoic, the different continents of Laurasia and Gondwana remain closely together, which is proved by the cosmopolitan flora of the Jurassic and the progression of Angiosperms in all continents in Mid-Cretaceous time. Floristic provinces appeared in the Late Cretaceous and in the Paleogene periods : the North-Atlantic province, the Siberian-Pacific province and the American-African province. From the Eocene epoch the individual evolutions of european and american floras indicate the opening of the Atlantic ocean., L'étude de la répartition des flores et de l'évolution des climats au cours des temps géologiques apporte des arguments intéressants en faveur de la dérive des continents. Au Carbonifère existait une masse continentale unique : la Pangée. Durant le Mésozoïque, celle-ci va se fractionner en différents blocs qui resteront en contact étroit jusqu'au Crétacé moyen ; en témoignent : la flore cosmopolite du Jurassique et du Wealdien ainsi que l'extension des Angiospermes dans tous les continents au Crétacé. Au Paléogène, l'ouverture de l'Atlantique apparaît nettement comme l'indiquent les évolutions distinctes des flores européenne et nord-américaine à partir de l'Éocène., Roche Emile. Paléobotanique, paléoclimatologie et dérive des continents. In: Sciences Géologiques. Bulletin, tome 27, n°1-2, 1974. Palynologie et dérive des continents. Problèmes posés par les aires pluricontinentales. pp. 9-24.