Ostracodes du Dévonien moyen et supérieur du Tafilalt (Maroc)

Forty-four ostracod species are recognised from the upper part of the Eifelian to the base of the Famennian of the Djebel Mech Irdane, Bou Tchrafine and El Atrous sections, in the Tafilalt. The majority are in open nomenclature, and one is new: Tubulibairdia tafilaltensis nov. sp. Ostracods belong principally to the Eifelian Mega-Assemblage and they are generally indicative of poorly oxygenated relatively deep marine environments below storm wave base. However, in the base of the Famennian of the Bou Tchrafine section, ostracods belong to the Myodocopid Mega-Assemblage indicative of strong hypoxic water conditions. They confirm that the hypoxic water conditions linked to the “Upper Kellwasser Horizon”, subsisted in North Africa, in the extreme base of the Famennian. Twenty-four ostracod species are recognized in the Djebel Mech Irdane Eifelian/Givetian stratotype, where the most important change in the ostracod fauna is related to the 40 cm-thick level of grey silty-marl located 10 cm below the boundary. However, this change is not indicative of an extinction event at this level. Three zones established on ostracods are recognized in the Frasnian and in the base of the Famennian of the Tafilalt.     

Description d'une nouvelle espèce et analyse morpho-fonctionnelle du genre Doryaspis White (Heterostraci) du Dévonien du Spitsberg

Doryaspis groenhorgensis nov. sp. is a new pteraspidiform from the lower devonian of Spitsbergen. The genus Doryaspis is now considered as the most abundant pteraspidiform of the Wood Bay formation, with five described species. Moreover, the pteraspidiform diversity of this formation has been under rated all along the XXth century. A morpho-functional analysis of the Doryaspis generic characters (e.g. flat dorsal shield, ventral pseudorostrum, long cornual plates) allows to consider two possible mode of life. However, none of the pelagic or benthic mode of life is better supported than the other. The same analysis introduce some interpretative hypothesis on histology and moving of the Pteraspidiformes. The Pteraspidiformes diversity of Spitsbergen is important for further Devonian circum-arctic comparisons (e.g. siberian platform).     

Stratigraphie et sédimentologie des « Couches rouges » continentales du Jurassique-Crétacé du Haut Atlas central (Maroc) : implications paléogéographiques et géodynamiques

In several synclines of the central High Atlas, the “Redbeds” following the closure of the marine Tethyan Atlasic trough during the Middle Jurassic are constituted by three successive formations or units of continental deposits dated recently with biostratigraphical elements. Some micropaleontological markers, mainly charophytes and ostracods, allow to precise the stratigraphy in agreement with a Bathonian-?Callovian assignment for the lower unit (Guettioua Formation), and in dating the middle and upper units. The Upper Jurassic, mainly the Kimmeridgian, is developed in the lower part of the middle unit (Iouaridene Formation). The Barremian has been recognized in this middle unit and in the upper unit (Jbel Sidal Formation). The Jurassic/Cretaceous boundary is thus delimited for the first time with micropaleontological data. These new data are very significant for the Atlasic history during the Mesozoic. The basaltic flows inserted in the continental Jurassic-Cretaceous deposits of the central High Atlas result from two separate events in the Middle Jurassic and in the Barremian. The tectogenesis in the basins is characterized by a polyphase process including notably a synsedimentary tectonic activity conspicuous in the Barremian. The evidence of marine to brackish intercalations allows moreover to date the first Cretaceous transgressive event on the NW boundary of the High Atlas during the Lower Barremian and to consider an Atlantic paleogeographical interaction. SW margin of the Tethyan trough in the Lower and Middle Jurassic, the central High Atlas is merged with the margin of the central Atlantic Ocean during the Lower Cretaceous.     

Charophytes, indicateurs de paléobathymétrie du lac Tigalmamine (Moyen Atlas, Maroc)

A paleolimnological study can be particularly accurate in situations where the species found in the sediments have persisted in the same lake and can provide a direct modern analogue for interpretation. Lake Tigalmamine, thus, represents an exceptionally favourable context, compared to most paleolakes in North Africa, as this site allows comparing the fossil remains of the Characeae to those produced by the living plants. Tigalmamine is a hydrosystem composed of three karstic lakes located at 1626 m above sea level in the Middle Atlas of Morocco. The site had been the subject of a 16 m long core taken in the center of the central lake under 16 m of water (core C 86 in Lamb and Kaars, 1995 [The Holocene 5 (1995) 400-408]). The section represents the total of the Holocene from 10,200 BP to Present (El Hamouti et al., 1991 [Comptes Rendus de l’Académie des Sciences de Paris 2 (1991) 259-265]; Lamb et al., 1995 [Nature 373 (1995) 134-137]). The latter published a synthesis of the pluridisciplinary studies conducted on this core. Also, the numerous gyrogonites isolated from that core had been determined as Chara hispida (Soulié-Märsche in Benkaddour, 1993 [Changements hydrologiques et climatiques dans le Moyen-Atlas marocain : chronologie, minéralogie, géochimie isotopique et élémentaire des sédiments lacustres de Tigalmamine. PhD thesis, Université Paris-Sud, Orsay (inédit)]). Further fieldwork at Tigalmamine by the authors of the present paper in year 2000 showed that Chara hispida is still present in the lake where it forms a belt of submerged vegetation restricted to the range of 2 to 9 m water depth. This paper describes the morphological and ecological characteristics of the extant Chara hispida as a reference for the interpretation of the fossil remains. Based on these data, the frequency changes of the gyrogonites in the core sediments become significant in terms of bathymetry. The detailed analysis of the charophytes from the core, as a complement to the previous studies, confirms the existence of four Holocene phases with lake level low stand at Tigalmamine. The aim of the present study is to enhance the value of the charophytes as a useful complementary tool for paleolimnological reconstruction.     

Le « Mégalosaure » (Dinosauria,Sauropoda) de Saint-Agnant (Charente-Maritime,France) : description et origine stratigraphique

The “Megalosaur” remains from Saint-Agnant (Charente-Maritime, France), reported as early as 1881 by Boissellier, are here described and figured for the first time. These bones, as well as a few additional specimens from the nearby locality of Soubise, belong in fact to an indeterminate sauropod. The stratigraphical position of these remains unambiguously indicates an infra-Cenomanian age. However, the presence in this area of continental deposits with Purbeckian and Wealden facies does not allow to decide between an earliest or late Early Cretaceous age.     

Le « nucléus Donggutuo » et sa signification dans l’industrie du paléolithique inférieur de Donggutuo, bassin de Nihewan, Chine du Nord

As one of the most important Lower Pleistocene sites of the Nihewan basin in North China, Donggutuo (DGT) site is well known for its fine retouched small tools and characters of flake industry. However, new excavations still reveal some new discoveries and educe some new issues to us. For example, the “DGT core” introduced in this article is a new discovered typotechnology and indicates new economic strategy of the local people, which was never known before in this area at the time of 1.1 Ma B.P. The paper provides general background and statistic analysis of DGT industry including special method applied to the “DGT core” and discusses possible influence of environmental change for the emerging of the “DGT core”. The “DGT core” shows a germinated microlithic tradition and reflects a cultural diversity of early humans in the Lower Paleolithic in North China.     

Les ostracodes des « Couches Rouges » du synclinal d’Aït Attab, Haut Atlas Central, Maroc : systématique, biostratigraphie, paléoécologie, paléobiogéographie

Ostracode assemblages, collected in the continental “Red Beds” of the Central High Atlas, Morocco, consist of 35 species, belonging to 17 genera, four of which are new and described herein. They allow to assign the lower member of the Iouaridène formation to the Upper Jurassic (?)-Upper Hauterivian and the Jbel Sidal formation to the Upper Hauterivian-Lower Aptian. Ostracode assemblages characterize lacustrine (freshwater) and lagoonal (oligo to mesohaline) environments. On the basis of limnic and lagoonal species, faunal connections are proposed for the Barremian-Aptian between Morocco and the Iberian Peninsula.     

Foraminifères benthiques complexes du Bathonien supérieur au Kimméridgien inférieur de la marge atlantique marocaine (« Bassin » d’Agadir) : stratigraphie et paléobiogéographie

The carbonate sediments of the Agadir Basin (Morocco) deposited during the Upper Bathonian-Lower Kimmeridgian p.p. interval are rich in agglutinated complex benthic foraminifera. The detailed inventory of several field-sections allows to identify and to describe these benthonic foraminifera, some of them being recorded for the first time in Morocco. They belong to the main genera Archaeosepta, Andersenolina, Praekurnubia, Pseudocyclammina, Everticyclammina, Alveosepta, Kurnubia, Parurgonina, Neokilianina, Labyrinthina and Rectocyclammina. The stratigraphic and paleobiogeographic distribution of these foraminifera seem to be related to the geodynamic events occurring on the Moroccan Atlantic margin during this time-interval. The stratigraphic distribution of the principal species is generally controlled by the occurrence of ammonites, brachiopods and of some foraminifera which are considered as good stratigraphic markers.     

Considérations sur l’extension géographique du Néolithique final à « livre de beurre » en Touraine et Poitou (France)

The “livre de beurre” blades debitage is classically attached to Grand-Pressigny country (Indre-et-Loire). This question is reconsidered by the autors to ligth on their knowledge of the sites and raw materials in a broadest geographic expanse: the South of Touraine and Poitou. Cultural attribution of this practice is also reconsidered and replaced in largest context.     

Habitat et mode de vie des chasseurs paléolithiques de la Caune de l'Arago (600 000-400 000 ans)

Several human occupations have been identified within the deposits of the Caune de l’Arago Cave site, dated from 700 000 years to 100 000 years old. The exceptional wealth of these archeological levels provides an opportunity for the study of different types of habitat and behavioral patterns of Paleolithic hunters between 600 000 and 400 000 years ago. Results from preliminary studies, carried out over the last 30 years on these archeological levels, allow for the proposition of a typology for cave habitats during the Middle Pleistocene in the south of France. In fact, four types of habitat were identified and defined. They have been described according to different characteristics such as, the thickness of the archeological accumulation, the animal species represented, the season during which the animals were hunted, the state of conservation of the fossils discovered, the morpho-technological and typological characteristics of the lithics, the categories of raw materials used and the territory exploited by the hominids inhabiting the cave, as defined by the raw materials represented. The four habitation types defined are: the long duration habitat, where the cave was used as a home base; the temporary seasonal habitat, in which case the cave served as a secondary campsite; the hunting stopover and the bivouac, during which the cave was used as a refuge for short term stays. Behavioral patterns appear to be directly related to the type of habitat and oriented towards a principal activity: hunting. The activities performed by the inhabitants of the cave seem to be more diversified during prolonged or seasonal occupations, whereas they appear to be reduced or very specialised during brief stays. Generally, The characteristics studied show that the Caune de l’Arago Cave site had multiple uses over time for Anteneandertalian family groups and hunters who left traces of their activities, allowing us to better understand their lifestyle.     

Mise en place des dépôts de pente du site moustérien de La Rouquette à Puycelci (Tarn) : étude sédimentologique et implications paléoclimatiques

La Rouquette (Puycelci, Tarn) Mousterian site sedimentological study allowed to define three large stratigraphic complexes into the Mousterian scree infilling. The granulometry, petrography, morphoscopy and clays mineralogy studies show variations that can be correlated with climatic variations, results corrobored by fauna and microfauna studies. Those sedimentary record variations are related to different sources which allow paleoclimatic interpretations and give a chronostratigraphic frame for this site.     

Heterosteginapapyracea Seguenza du Miocène du Corridor Sud-Rifain (Maroc) : biométrie et particularités paléoécologiques

Biometric study of the inner features of Heterostegina specimens preserved in tortonian sediments of the oued Yhoudi member allows to confirm the presence of species Heterostegina papyracea Seguenza, 1880. Analysis of both large and small components of the foraminiferal assemblage in all examined samples establishes the dominant character of species Heterostegina papyracea Seguenza (more than 60% of total benthic foraminifera). The assemblage of small benthic foraminifera associated with the Heterostegina is different from that described from Recent sediments, as well as from Miocene sediments of Calabria and Spain. In order to explain this result, two hypotheses can be put forward: (1) the Tortonian Heterostegina from Morocco proliferated abundantly in very shallow environments in association with small foraminifera (i.e. abundant Ammonia beccarii). (2) Because of powerful tidal currents in the South Rifian Corridor, Heterostegina tests were probably transferred after death. This transfer could possibly be due to the narrowness of the South Rifian Corridor in the Early Late Tortonian and its position between the Atlantic and the Mediterranean. Similar cases foraminiferal displacements are also known from modern basins. This study illustrates the difficulties in reconstructing the paleogeography of the studied area and the importance of considering all available components of the assemblage.     

Euxinocythere (Ostracoda, Cytheridae, Leptocytherinae) du Miocène supérieur du Bassin de Turiec (Slovaquie) : taxonomie et paléoécologie

Eight new species of the family Cytheridae have been identified in the Upper Miocene deposits of the Turiec Basin (Slovakia), a small isolated intermountain depression. Six species are new - Euxinocythere aphroditae, E. delicata, E. lactea, E. minuscula, E. quadricostata, E. satyrica - and two are kept in open nomenclature. Their attribution to the genus Euxinocythere is based on arrangement of the hinge elements and of anterior marginal zone. This genus is known from brackish ostracod assemblages of the Paratethys and the Eastern Mediterranean while the species from the Turiec Basin are associated to fresh-water assemblages. The Euxinocythere have been found in littoral as well in deep limnic environment.     

Une lame de faucille sous la stèle gravée Chalcolithique dite du « Chef de tribu », Vallée des Merveilles, région du Mont Bego, Tende, Alpes-Maritimes

The carved stele known as the “head of the tribe”, attributed to the Chalcolithic, erected at an altitude of 2290 m in the chaos of blocks in the Merveilles torrent in the Mont Bego region at Tende, was removed from its original standing place. Earth extracted from under the stele and sieved yielded a sickle blade in very fine and homogeneous Bedoulian pale biege translucid flint, pressure flaked on a heated core. The blade bears a light polish caused by cereal harvesting. This sickle blade is similar to those widely used in the southern Chassey culture (4300 to 3000 years before our era) but also sometimes in the Campaniform culture, during the ancient and middle Bronze age, like in Murée cave, in the Verdon gorges. The location of the sickle blade at the foot of the carved stele, known as the “head of the tribe”, is not just coincidental. It is highly probable that the blade was intentionally placed beside this rock. It is seemingly during a ritual ceremony that this sickle blade, probably still inserted in a wooden handle, was intentionally placed, in a propitious gesture or as an offering, beside the stele known as the “head of the tribe”.     

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.     

Gestion de la « crise du Mo » en 2010 par un service de médecine nucléaire hospitalier au Luxembourg : bilan

To face the challenges of the “⁹⁹Mo crisis” on a nuclear medicine department level, strategies were implemented to maintain numbers of scintigraphies as usual. We evaluated the efficiency of the measures. Using ^99mTc more rationally led to more profitable generator utilization. As long as the amount of ^99mTc at disposal (> 110%, 90–110% (= standard), 70–90%, 50–70%, 30–50% and < 30%) was greater than 30% of the standard, weekly numbers of ^99mTc-based investigations remained at “standard” level. Cost per mCi of administered ^99mTc remained unchanged. The successfully managed “⁹⁹Mo crisis” was based upon a rigorous organization as well as goodwill of all implicated staff, at the cost however of a lesser patient service. Punctual flexibility of staff members, adapted to the fluctuating work load, allowed global balance between numbers of required and delivered working hours. As efficient crisis management is tedious, generalization of the model cannot be thought of. To guarantee secure future availability of ^99mTc, projects for new nuclear reactors dedicated to producing ⁹⁹Mo are first choice.     

Isotopes stables (C,N) du collagène des mammouths de Mezhyrich (Epigravettien,Ukraine) : implications paléoécologiques

The mammoth steppe ecosystem was characterized by a high diversity in large mammals species distributed on a vast geographical range. The isotopic analyses of the collagen of the faunal remains from this context testified the niche partitioning among large herbivores with a specialization in the types of consumed plants. In the case of the mammoth (Mammuthus primigenius), systematic higher abundances in ¹⁵N are found for this species compared to those of other grazers in Eurasia and Alaska during the Upper Palaeolithic. This distinct isotopic signature reflects a specific ecological niche. The analyses of mammoth remains at the Epigravettian site of Mezhyrich (15,000–14,300 conv BP) reveal low abundances in ¹⁵N that are equivalent to those of the associated horses. Thus, the mammoth of Mezhyrich experienced a significant change in their environment and diet that probably led to the loss of their ecological niche. A likely direct competition with other large herbivores and the possible predation by wolves and human populations should be considered for the mammoth of the Ukrainian plains, long before their extirpation from the region.     

Les assemblages lithiques des niveaux du Paléolithique moyen de l’Abri des Pêcheurs (Ardèche, Sud-Est de la France): Des occupations néandertaliennes récurrentes dans un « fossé »

The Abri des Pêcheurs has yielded an extraordinary sequence with Middle and Upper Palaeolithic levels. Humans came and stayed in a ditch-cave that has been filled in along time. During Middle Palaeolithic occupations, they used first quartz, and this site is the only case in this area. Assemblages show similar technological behaviour along time. Flint is few employed and arrived as flakes from different areas if we consider its geological variety. Functions of the site are not well established. The base of the sequence has yielded sediments with a mixing of ibex, carnivore bones and artefacts. The study of the lithic assemblages brings information on the processing systems used on quartz and flint during occupations which left few evidence and used local stones while flint is available not far from the site. Hypothesis on short and specialized occupations is discussed.     

Galets aménagés en provenance des terrasses supérieures du Rhône au sud de Lyon (Sud-Est de la France)

Between 1990 and 1993, we found 175 pebble-tools and two flake-tools on the western high-terrace south of Lyon (Southeast, France) at two different levels (290 m and 235 m NN). Most of them show the classical spectrum of choppers and chopping-tools, joined by six protobifaces. They all belong to the developed Olduvan (Olduvan II). On the lower terrace, corresponding with its younger age, we met a more progressive pebble-tool culture. Both stocks are secondary sites, brought from the East by the most extreme tongue of the Rhône glacier and, therefore, cannot be dated exactly.     

Kabazi II (Crimée, Ukraine) : un site d'abattage et de boucherie du Paléolithique moyen

The site of Kabazi II is located on the second row of the Crimea Mounts in the west side of peninsula. The study presented in this article is about the archaeological material of the II/8 level. This level was excavated in 1987 and 1994. It is date of the Hengelo Interstadial. The lithic tools discovered in this level are attributed to the Western Crimea Mousterian (WCM). The E. hydruntinus dominates with more than 90% of the determinated remains. The crossed analysis of the results given by the studies of lithic and bone materials allowed to clarify the chronology, the environment and also the technical and subsistence behaviours of the Neandertals of the II/8 level of Kabazi II. These new interpretations are presented here.