Les kystes de dinoflagellés des Argiles Ostréennes du Bassin de Paris, France

Palynological studies realized from a borehole drilled on the site of ANDRA (Agence Nationale pour la gestion des Déchets RAdioactifs; Aube Centre near Soulaines, Paris Basin, France) show a sedimentary discontinuity between, on one hand, the Argiles à Plicatules (lower Aptian in age) and Argiles Ostréennes (Lower Barremian/Upper Barremian in age) and, on the other hand, between these same Argiles Ostréennes and the Calcaire à Spatangues (Lower Hauterivian). These conclusions argue against the chronostratigraphical subdivision recently proposed on the basis of sequence stratigraphical and sedimentological interpretations.     

Succession des peuplements d’échinides du Crétacé inférieur dans le Haut Atlas atlantique (Maroc) ; révision systématique et intérêt stratigraphique

The rich echinoid fauna from the Lower Cretaceous of the Agadir, Haha and Essaouira basins has been revised taxonomically, based on new and abundant collections. Forty-seven species have been identified, of which 20 are reported for the first time from this region and a further three represent new species left in open nomenclature. Their stratigraphic ranges have been determined accurately by reference to the regional ammonite zonation. However, it is also possible to use a local biostratigraphical scheme based on the echinoid succession, where ammonites are rare. The Toxasteridae, which are very abundant and underwent rapid evolution, are the most useful biostratigraphically. The genus Toxaster appears in the Lower Berriasian and continues until the Gargasian passing through the following succession: T. africanus, T. granosus, T. kiliani, T. lorioli, T. obtusus, T. exilis, T. retusus, T. maurus, T. peroni, T. collegnoi. The presence of Eoholaster, Macraster, Douvillaster, Palhemiaster, Heteraster and Pygopyrina is signaled for the first time in the Atlantic High Atlas region.     

Ostracodes bathyaux du Crétacé terminal - Éocène moyen en Atlantique tropical (Plateau de Demerara, Leg 207)

Ostracode faunal assemblages which lived in bathyal environments are analysed from uppermost Maastrichtian - middle Eocene sediments of sites 1260 and 1261, drilled on the distal margin of Demerara, off Surinam (Leg 207, western tropical Atlantic). As for numerous other groups, the Cretaceous/Tertiary mass extinction event led to the disappearance of numerous bathyal ostracode species and it was followed by a very slow recovery during the Palaeocene. It appears that this extinction event was more devastating for detritus-feeder ostracode species than for filter or silt-eater groups, which crossed the K/T boundary without any or little morphological change. This extinction selectivity may be explained by the drop in productivity of surface waters which took place at the K/T boundary. Finally, psychrospheric ostracode species were encountered in Middle Eocene sediments, confirming thus the general cooling of deep oceanic realm recognised in general for this time interval.     

Les Schackoïnes (Foraminifères planctoniques) de l’Albien supérieur du Blake Nose (marge atlantique de la Floride, Leg ODP 171B)

A study of rather rich and well-preserved material from Upper Albian levels of Site 1050 of ODP Leg 171B led us to review the criteria used in the subdivision of the schackoinids into two genera and to describe a new morphotype, Schackoina leckiei n. sp., the phylogenetic position of which is examined within the group.     

Zonation des brachiopodes du Jurassique moyen sur la marge sud de la Téthys occidentale (Maroc, Algérie occidentale): Comparaison avec la marge nord-téthysienne française

A new and yet unpublished palaeontological revision of very important collections accomplished these last thirty years in many localities of Morocco and Western Algeria joined to the already published data, allow us to propose a biostratigraphical succession of the Middle Jurassic Brachiopods suitable to the Southern Margin of the Western Tethys. This Brachiopod scale is correlated with the standard chronostratigraphy based on ammonites. It involves eight zones and six sub-zones separated by five interval zones where Brachiopods are missing. Moreover, brachiopods have not been discovered in Early Aalenian and Late Callovian. Afterwards, the two brachiopod zonations established on the northern and southern margins of the Western Tethys are compared. On a paleontological plane, a new definition of the species Burmirhynchiaathiensis warrants to precise its vertical distribution (Parkinsoni and Zigzag zones) and to give a better distinction with Burmirhynchiatermierae (Humphriesianum and Niortense zones).     

Les industries paléolithiques du bassin de Bose (Chine du Sud)

About eighty Paleolithic sites are presently known in Bose basin (West of Guangxi autonomous region, South China). The sites are extensively spread on the fourth terrace of the Youjiang River. They are dated to 0.8 my, thanks to the presence in the archaeological layers of tektites, residues from a major meteoritic event, in association with the archeological materials. Only about twenty sites have been actually excavated and handaxes have been very recently discovered in stratigraphic context. The archeological material exclusively includes lithic industry which is mainly constituted by unifacial pebble tools made on coarse grain rocks: choppers, but also handaxes and picks. The technology used is very simple and there are no spheroids which usually characterize a lot of Chinese sites of this period. Bose handaxes, thought their number is quite low, remind of the western Acheulian.     

Les vagues de peuplements humains au Pléistocène inférieur et moyen dans le bassin de la Loire moyenne, région Centre, France. Apports de l’étude des formations fluviatiles

Evidence of earliest human settlements had been searched in the alluvial formations laid down in the Middle Loire Basin. Many stepped sheets deposited during the successive interglacial-glacial quaternary cycles are studied in four valleys of the Loire tributaries: the Creuse, Indre, Cher and Loir rivers. These sandy remnants are systematically dated, using the Electron Spin Resonance method applied on bleached fluvial quartz. Five settlements which contain very Early Palaeolithic industries with Mode 1 technology were occupied during the Lower Pleistocene. About eighty sites with hand-axe assemblages are observed in Middle Pleistocene remnants; nine of these are described in this paper. The results theorize that the geographical center of France (47°N) would be reached by two influxes of human populations with an interval around 400 years, because major climatic pejorations, particularly at the end of the Lower Pleistocene. These two populations produced lithic industries with many differences in supply of raw materials and in techniques of striking. Not any typologic link had been observed joining the two industrial unities.     

Ostracodes limniques de la Formation d'Irbzer, Crétacé terminal du Moyen-Atlas, Maroc : taxonomie, biostratigraphie, paléoécologie, paléobiogéographie

An association of limnic ostracodes has been discovered in the upper part of the Irbzer Formation, of Maastrichtian age, in the Moroccan Middle-Atlas. A new species is described, Gomphocythere achloujensis nov. sp. Paracandona occitanica, which is very common in terminal Cretaceous non-marine deposits of southern Europe (France, Spain), is found for the first time on the south Tethyan margin.     

Les cétacés des gravures rupestres néolithiques de Bangu-dae (Corée du Sud) et les débuts de la chasse à la baleine dans le Pacifique nord-ouest

The Neolithic site of Bangu-dae (6000-1000 B.C.), south-east of the Korean peninsula, presents numerous rock carvings of cetaceans (n = 46, 19.9% of the figures), and especially large species. Among these two families of baleen whales (Balaenidae and Balaenopteridae) and the sperm whale can be identified. This site also presents whaling scenes suggesting that the Neolithic populations who lived along the coast of Korea were among the first to take advantage of coastal whales. All these carvings give exceptional evidence on the prehistoric beginning of whaling.     

Révision des rudistes crétacés (Bivalvia) de la Paléontologiefrançaise d’Alcide d’Orbigny

In the volume IV of the “Paléontologiefrançaise”, A. d’Orbigny deals in particular with Cretaceous rudists. Numerous type specimens of Hippuritidae, Caprinidae, Radiolitidae, Caprotinidae, Requieniidae belonging to his collection and deposited in the Muséumnationald’histoirenaturelle, Paris. Among the 78 species that he has studied, A. d’Orbigny introduced 41 as new ones. This review presents a picture of all types with a comment on the original definition, and set the statute, and the precise stratigraphical level of illustrated forms. The present work gives rise to the designation of 40 lectotypes, two syntypes and three neotypes.     

Palynostratigraphie du Callovien-Oxfordien (Jurassique) dans les Terres noires, sud-est France

The Terre noires are monotonous sedimentary deposits comprising thick, dark marls and thin carbonaceous layers. They constitute a lithostratigraphical group known in the major part of the SE French Basin. In the East of this basin this group, dated from late Bajocian to mid Oxfordian, is well developed; on the other hand on the West, it is reduced until it disappears locally on the border of the Massif Central. In the East, the succession is precisely dated by ammonites, whereas in the west, ammonites are not consistently present, and do not permit the same precision. Analysis of dinoflagellate cyst assemblages, at the Callovian-Oxfordian boundary, show that it is possible to correlate the eastern to the western succession. Two marker species allow the correlation of four outcrop sections. The first index, Wanaea fimbriata, is well known; its first appearance datum is exactly at the Callovian-Oxfordian limit in the Boreal and Mediterranean realms. It is the index taxon of the palynological parazone Wfi. The second index, Stephanelytron ceto, an endemic taxon in the SE French, has its last appearance datum within the Scarburghense horizon, the second subzone of the oldest zone of the Oxfordian (Mariae zone). The first section studied was sampled in the east part of the basin (Hautes Alpes department). It corresponds to the maxima of marine deposits and is used as the palynostratigraphical reference. The three other sections analyzed, sampled in the west part of the basin (Ardèche department) where marine deposits are more condensed, are correlated and dated due to dinoflagellate cyst markers observed in the reference section. These results indicate that dinoflagellate cysts are a reliable correlation tool. Batiacasphaera rugosa (Courtinat, 1980) nov. comb is proposed.     

Les industries acheuléennes de la France septentrionale

The excavations of several open air sites in Northern France and, especially in the Somme basin, have given numerous data concerning the age and the environment of the human occupations for the period from MIS 12 to MIS 8. The quality of the raw material and the function of the different sites have a great effect on the composition of the lithic assemblages as it has been seen for the different sites located near the confluence of the Somme and Avre (Cagny-la Garenne, Cagny-l’Épinette, Ferme de l’Épinette, Gentelles). The characteristics of the lithic industries of Gouzeaucourt show the complexity of the transition from Lower to Middle Palaeolithic.     

Proposition d’une échelle chronométrique autour de la limite Crétacé-Paléogène par cyclostratigraphie : coupe de l’Aïn Settara (Kalaat Senan, Tunisie centrale)

The Aïn Settara section (Kalaat Senan, Central Tunisia) exposes in very good conditions a continuous marl-limestone alternation, going from the Upper Maastrichtian to the Danian. The Cretaceous-Palaeogene boundary is particularly better exposed than it is in the El Kef type section. The studied section reveals, at first, a typical bed-interbed decimetric to metric limestone-marl alternation. Upon this one, at a meter scale, a second mode of alternation is superimposed: between, firstly, sharp and thick bed-interbed bundles, and, secondly, more diffuse and thinner bundles, which are more difficult to split into beds and interbeds. This frame deals with the equinoxial-precession climatic-forcing. The bed-interbed alternation corresponds to the precession of 21.3 ka average period. The clear bundle-diffuse bundle alternation, comes from the amplitude modulation of the precession by the circa 100 ka period of the eccentricity. This succession is used to build a time floating-scale, adjusted on the Cretaceous-Palaeogene boundary. Fixing this boundary to the value of -65.0 Ma, we obtain a chronometric time-scale, going, for our section, from -65.8 up to -64.4 Ma, that is a total duration of 1.3 m.y. This scale allows to better localize in time the sedimentary and biological phenomenons, which encompass the Cretaceous-Palaeogene boundary.     

Distribution de Megaporellaboulangeri Deloffre et Beun, 1986 (algue dasycladale) dans le Jurassique du bassin atlantique marocain

The recent biostratigraphic and micropaleontologic works permitted to specify the distribution of Megaporellaboulangeri Deloffre and Beun in the Jurassic of the Moroccan Atlantic basin. The lower limit of the extension of this dasycladale alga, earlier attribued to the Early Kimmeridgian by Deloffre and Beun (1986), is currently placed in the Early Callovian, on the basis of the age provided by Megaporellaboulangeri biozone. The Otternstellaarabica biozone dates the upper limit of the extension of the species of the Early Oxfordian. Megaporellaboulangeri proliferates in the borders of the basin where the internal lagoons facies dominate, however it is absent in the western parts with open sea facies.     

Des Miliolacea aux Alveolinacea (grands foraminifères): la faune du Crétacé supérieur et du Tertiaire inférieur du Chiapas (S.E. Mexique)

Found in Chiapas (South-East of Mexico), Praealveolina michaudi nov. sp. and Chubbina jamaicensis (of Campanian-Maestrichtian age) are described, both evolved from Nummoloculina sp. while Raadshoovenia guatemalensis (upper Paleocene-lower Eocene) arises from Quinqueloculina. We precisely analyze and modelize the nepionic coiling during the evolutionary change from Miliolacea to Alveolinacea. During ontogenesis as well as during phylogenesis, quinqueloculine coiling progresses to streptospiral and then to planispiral chamber arrangement with the increase of volume of embryo and of chambers. Appearance of these large foraminifers are understood as a consequence of the rise of K-strategies in their mode of life, following the development of photosynthetic symbioses.     

Utilisation du bois de feu par les chasseurs-cueilleurs de la « Cidade de Pedra » à partir de l’Holocène moyen (Brésil Central,Mato Grosso,Rondonópolis)

Located in the south-western Mato Grosso state (Central Brazil), the vast territory of the Cidade de Pedra was continuously occupied since the mid-Holocene by several groups of hunter-gatherers. Rock paintings, lithic industries, ceramics, ornaments, combustion remains (etc.) testify their passages in the many rock art sites discovered since 1983. In this paper are presented the results of the first anthracological analyzes conducted in four of these rock shelters. The studies were realized from macro-remains carbonized from hearths, embers and concentrations. From the taxonomic identification of charcoal, the objectives are to highlight the practices of hunter-gatherers related to the collection of wood and the environment in which they evolved for nearly 5000 years. The results indicate that they practiced an opportunistic collection mainly focused on dry wood available in the vegetation around the sites. They evolved in an environment similar to that currently characterizes the region, a typical flora of the Cerrado Biome and seasonal climate.     

Données paléoenvironnementales sur le Vraconnien/Cénomanien de la région de Tébessa (Atlas Saharien,nord-est Algérie). Caractérisation de l’OAE2

The micropalaeontological content of five sections, located in Northeastern Algeria (Saharan Atlas) was investigated by means of washing/counting of microfossils in marly levels, and microfacies analyses of calcareous levels. In these levels of Upper Cretaceous age, hundred species of foraminifera were identified but only about 15 species of ostracoda and about ten of radiolaria. This work allows, first of all, to establish a rather precise stratigraphic frame, in particular by means of studying planktonic foraminifera. Two to five biozones were defined, between the Vraconnian (Th. Appenninica biozone) and the early Turonian (Whiteinella archaeocretacea biozone, then Helvetoglobotruncana Helvetica biozone for certain sections). Secondly, the quantitative analyses led on foraminifera allowed the definition of palaeoenvironment. The ratio P/P+B, generally very high, coupled with a little diversified benthonic microfauna, indicates a calm and deep environment, of external platform or slope type. Furthermore, at numerous levels, various indications give evidence of the existence of a strong surface productivity (presence of upwellings), responsible for the proliferation of radiolaria (late Vraconnian/early Cenomanian especially) or of globular planktonic foraminifera (hedbergellids/heterohelicids); being both associated with low-oxygen deep waters. Two anoxic events were also revealed, the first one at the end of Vraconnian (OAE1d) and the second at the end of Cenomanian (OAE2). This last event in particular was characterized on all the sections, in a more or less detailed way, thanks to the identification of certain indicator: Heterohelix “bloom”, “filament” event, disappearance of rotaliporids, presence of “blackshales” strongly enriched in organic matter (Bahloul levels).     

Étude de Pseudanogmius maiseyi gen. et sp. nov., poisson marin (Teleostei, Tselfatiiformes) du Crétacé supérieur du Kansas (États-Unis)

The osteology of Pseudanogmius maiseyi gen. and sp. nov., a marine teleost of the Upper Cretaceous of Kansas, is studied. This fish belongs to the order Tselfatiiformes and more particularly to the group with a more or less flat skull roof and with large, quadrangular and joined parietals. Pseudanogmius maiseyi, formerly named Anogmius sp. by Hay (1903), differs from Bananogmius and the other genera known in the order by three autapomorphies: an elongated and very narrow vomer, a peculiar relief of the toothed part of the parasphenoid, and transverse processes on the caudal vertebrae. Within the order, it shows a few evolved characters, such as the loss of the preural 1 hemal arch and of the sixth autogenous hypural and by the shortening of the preural 1 neural spine.     

« Terre des cités fortifiées ». Sites de la civilisation des steppes de l’époque du Bronze moyen en Oural du Sud

The “Earth of fortified settlement” is one of the last big discoveries of the end of the xx^th century. Situated on the oriental slopes of the mounts of Ural, fortified settlement, date the Middle Bronze Age. These strengthened structures are particular in the archaeology of steppes. They were built according to geometrical plans, Cities in oval being the most ancient, the rectangular cities being the most recent. The most remarkable are together of strengthened structures appropriate for the culture of Sintachta-Arkaïm. This city distinguishes itself from the others by the unique integrity of the works of fortification and by the graves which are connected to these last ones. Situated on a prominence, Arkaim consists of two defensive walls, maybe of a third, the rampart and the ditch. The space between the defensive walls was occupied by the houses of trapezoidal shape and directed as beams to the center of the city. The center of the city, the rectangular shape, was not built and formed a place where foyers were found. Complex entrances were at the four corner of the city. The excavations of fortified settlement and graves allowed to have an idea on the level of development of the everyday life at the time of the Middle Bronze Age in transuralian plains.     

Les pointes pseudo-Levallois du gisement moustérien Le Rissori, à Masnuy-Saint-Jean (Hainaut, Belgique)

The 1985-1992 excavation of the Middle Palaeolithic site Le Rissori provided 202 pseudo-Levallois points, distributed in four successive Mousterian series covering a period of time of about 200,000 years. The reference object is the typical five and more sided polygonal point. It is an asymmetrical variety of “débordant” flakes with their own striking platform, at the difference of classical “débordant”, the obliquity of which makes the difference in the following three categories : typical polygonals, atypical polygonals, and classical subtriangulars. The operating scheme - which is the same for all the categories- gives some large and thick flakes after “débitage”. The typical pseudo-Levallois points (polygonal and classical of type A) show two thick sides : the butt and the concave reshaped “débordant” side which is corresponding to the partial overcutting of the active striking platform of an uni- or bipolar recurrent Levallois core. Their function stands in latero-longitudinal (distal or proximal) convexities restoration, the usual process of which can only be restored with difficulties, because of the importance of the removed volume.Typical, polygonal and classical points become perfectly integrated into the Levallois system ; their technological scheme shows a lot of similarities, evoking an antesaalian evolution and origin. The pseudo-Levallois point so appears like a product with a technological vocation, which is revealing a latero-longitudinal restoration. The pseudo-Levallois point is moreover confirming the presence of a uni- or bipolar recurrent Levallois “débitage” with blades or lengthened flakes.