Le site de Longgupo dans son environnement géologique et géomorphologique

On a regional scale, Longgupo is found within a karstic landscape of fenglin-ouvala developed in the Triassic limestones of the Yangtze platform. After several seasons, it is now possible to define and propose a scenario for the formation of the site. During one of the intense karstification phases during the Cretaceous or early Tertiary, karstic conduits were created deep in the substratum. In concert with these deep flows and by karstic collapse, a cave was created. With the start of Himalayan uplift during the Oligocene and Miocene, the beginning of fluvial cutting was reflected by the partial erosion of the upper sandstone formations and the creation of the Miaoyu Valley. This action opened the cave, which would later be occupied by the hominid groups that interest us here. Probably at the end of the Tertiary, the cave, open at the bottom of the valley slope and facing upstream, began to be filled with alluvial deposits from the valley. The basal deposits (C III 10 of the current stratigraphic sequence, levels 20-13 of the first sequence) begin with black clays; at the Plio-Pleistocene transition, deposits become clearly alluvial, increasingly marked by reworking of surface and karstic clays and by systematically coarser contributions. During the deposition period of archaeological complexes III/III’ (previously levels 12-6), karstic collapse appears to have still been active. During the Lower Pleistocene sensu lato, the coarse nature of the deposits becomes accentuated. The material of complex II (previously levels 5-2) is a deposit that is clearly heterometric and coarse, composed at the end mainly of gravels, pebbles and more or less rounded blocks in a clayey matrix. At the conclusion of this new stage, the cave was entirely filled and, purely and simply, disappeared from the landscape. As the valley deepened during the Middle and Upper Pleistocene, the Longgupo slope underwent profound changes, the last of the limestone blocks disappeared from the slope limit and the archaeological site was protected by the coarse breccias that carpeted the slope. The main cause for the sedimentation processes at the site of Longgupo is the hydrosystem of the Miaoyu he, although injections of karstic type sensu stricto cannot be excluded. All of the arguments effectively support alluvial deposition: pebbles, an alternation of coarse and clayey beds, systematic and repeated granulometric decrease. But the stratigraphic disposition was disturbed by deformations due to gravity and karstic origins; the alluvial sediments, rendered plastic by the high proportion of clayey beds, were deformed by gravity (deformation of beds, faults, slopes) following the direction of the slope and by karstic collapse along the two limestone walls north and south of the sites (in sub-parallel faults to the south and by circular aspiration to the north). To this is added a calcitic consolidation of the upper levels that made it difficult to excavate complex C II. The stratigraphic disposition of the archaeological levels at Longgupo is now well understood. It has thus been possible to collect samples for absolute dating, to be published soon.     

Introduction à l’étude du site de Longgupo

The site of Longgupo, discovered in 1984, is located south of the crossing of the Three Gorges of the Yangtze, in the eastern part of Chongqing Province. Situated on the limestone slope of the Miaoyu Valley, three excavation campaigns have been carried out since 1985. The first two seasons took place from 1985–1988 and 1997–1998, directed by W.B. Huang and the last campaign from 2003–2006 by E. Boëda and Y.M. Hou. After the first two campaigns, the presence of several bones, with an estimated age of 1.9 My, notably including a mandible fragment attributed to a hominid² and the discovery of more than 20 lithic artifacts incited not only great interest in the scientific community, but controversy as well since these data contradicted diffusion models of the first hominids out of Africa. Paleoanthropological data often being privileged over other data, including lithic artifacts, the anthropic nature of the site was contested. Yet the few artifacts from the initial excavations irrefutably demonstrate their manufacture by humans, in particular those in exogenous stone. To definitively re-establish the authenticity of this site by applying the latest investigative methods, a new Franco-Chinese campaign was organized. The objective of the 2003–2006 field seasons focused on understanding and analysis of the archaeological data in their geomorphological and stratigraphic contexts.     

甘肃苏苗塬头地点石制品特征与古环境分析

苏苗塬头地点位于甘肃省平凉市庄浪县东北部, 埋藏于章麻河二级阶地的典型马兰黄土中。经剖面清理和地表采集, 2002和2004年在该地点共获得石制品2318件, 本文以集中分布区出土(2166件)和地表采集(48件)共2214件石制品为主要研究对象。该批石制品以石片、碎片和碎屑为主, 有少量石核和工具。剥片技术以砸击法为主, 锤击法为辅, 鲜见第二步加工。石制品原料主要为来自现代河床或阶地底部砾石层的脉石英。炭屑加速器质谱(AMS 14C)年代测试和多环境代用指标分析显示, 苏苗塬头为一处旧石器时代晚期文化地点, 人类活动主要发生于气候干冷的末次盛冰期(约距今2.4—1.8万年), 反映了古人类较强的环境适应能力。     

Étude préliminaire des industries archaïques de faciès Oldowayen du site de Hummal (El Kowm, Syrie centrale)

The spring site of Hummal is located in Central Syria, near the village of El Kowm between the Euphrates basin and the desert steppe stretching from Palmyra to Deir-ez-Zor. In 1966 the well was noted in a survey as Bir Onusi and a short preliminary study was carried out at the beginning of the 1980s. Since 1997, the Institute for Prehistory and Archaeological Science of the University of Basel has undertaken a complete interdisciplinary research program of this major site under the direction of J.M Le Tensorer, supported by the Swiss National Science Foundation and associated with the Directorate General of Antiquities and Museums of Syria under the direction of S. Muhesen. The site of Hummal is a prominent mound at an artesian spring built out of the sediments, which piled up during the whole Quaternary. Tectonic faults in the bed rock enabled the underlying water in a karstic system to flow out into a dolina, which trapped lacustrine, limnic and aeolian sediments since the Oldest Pleistocene. The impressive stratigraphy – 20 m high – comprises 23 geological units preserving a great number of archaeological levels. It covers an extremely long period of time ranging from the Oldest Palaeolithic (Oldowan) to Upper Palaeolithic (Aurignacian) over more than a million years. This impressive Old and Middle Palaeolithic sequence comprises several layers of Oldowan-like assemblage (23-16), an Acheuleo-Tayacian complex (14-13), five layers of Yabrudian (12-8) at least four levels of Hummalian (7, 6c, 6b, 6a) and a thick sediment complex with 8 Mousterian layers, each of them liable to be subdivided into several sublayers. The lithic industry in the lowest levels of the Hummal sequence, associated with abundant remains of large mammals, can be characterized by non-modified, quite fresh flakes, with, once in a while, traces of use but never bearing intentional retouches. Theses flakes are found with pebble-tools: choppers, chopping-tools, polyhedrons, bolas and core-like artifacts. This assemblage is typical in a broad sense of archaic Palaeolithic whose debitage corresponds to mode 1. From a techno-typological point of view, this industry tallies quite well with the so-called Oldowan stage. It shows remarkable similarities with the oldest assemblages at Ubeidiya but, so far, with no occurrence of bifacial knapping. If the layers 17 and 18 of Hummal relate to this period dating back to 1.6 to 1.2 million years, these levels would be the oldest ones ever found in central Syria. However, as we have no absolute dating at our disposal so far, we will remain careful in assigning a chronological time span for these layers. For this area, from a stratigraphic point of view, the Oldowan levels of Hummal occur before the Acheulean and certainly before the Acheulean sequence of El Meirah (region of El Kowm) which is itself related to the period before Matuyama-Brunhes paleomagnetic reverse. Dating of the lowest sequence of Hummal is underway. If we take into account stratigraphic and techno-typological observations, we assume that the Oldowan-like levels of the site should be older than one million years at least. The sequence of Hummal is one of the largest in the Near-East. Therefore, it can be regarded as a key-site for world prehistory.     

藏南江孜地区古近纪甲查拉组孢粉组合及古环境分析

甲查拉组位于藏南特提斯喜马拉雅北带的江孜盆地,是江孜地区的最高海相地层,被视为新特提斯洋关闭时代的主要证据。通过对甲查拉组剖面的孢粉分析,自下而上划分为3个孢粉组合带:1 Ulmipollenites minor+Ulmoideipites-Myricipites组合带;2 Quercoidites-Caryapollenites组合带;3 Abiespollenites-Betulaceoipollenites+Betulaepollenites组合带。甲查拉组孢粉植物群揭示出其沉积自晚古新世开始,其沉积结束可能延续到早渐新世。推测晚古新世—早始新世为温暖湿润的暖温带或亚热带气候,始新世中晚期为温暖、潮湿的亚热带气候,早渐新世为温和湿润的暖温带气候。     

Palynological Analysis of the Late Cenozoic and Its Significance in Fulaerji,Heilongjiang Province

The pollen analytical investigation of 226.07 m,, deep QH70 core from Fulaerji district in the city of Qiqihar, Heilongjiang province have been carried out. Based on the characteristics of QH70 core sporo-pollen assemblages, seven pollen zones may be subdivided in the order as follows: The first zone (Ⅰ) belongs to early period of the Late Cretaceous. When the flora was mainly composed of gymnosperm, the next was fern and a little original angisperm. Here the climate was hot and wet and the vegetation showed tropical-subtropical in aspects. In this core the author didn't find the Palaeogene flora. The Ⅱ–Ⅲ zones belonging to the Late Tertiary are characterized by predominance of arboreal pollens, mainly consisting of Amentiferae and some conifers. The flora of the Neogene was mainly composed of Pinus, Betula, Castanea, Ulmus, Corylus, Alnus, ,Juglans, Quercus, Carya, Fagus, Tsuga etc. some subtropical species of Hamamelis, Liquidambar, Castanopsis, Melia. Myrica and Taxodiaceae which still existed. The climate was warm and humid with the annual temperature higher than that of the present. As to the last period of the third zone (Ⅲ) the assemblage of herbaceous plants and semi-shrub were predominant. The climate was changed into cool and less dry. The fouth pollen zone (Ⅳ) is represented by herbaceous plants such as Artemisia, Chenopodiaceae, Gramineae, Polygonaceae etc. indicating the Fulaerji was covered by cold-temperature grassland with a cold and dry climate. According:to temperature decreasing at this zone, magnetostratigraphy and thermoluminescence dating we may take the start of the Ⅳ zone as the mark of the beginning of Quaternary in this region. The age of the boundary between Pliocene and Pleistocene might be 2.4 million years or so. The geological age of pollen zones Ⅳ–Ⅶ, is assigned to Pleistocene. The characteritics of the sporo-pollen assemblage at these zones are quite different from one another. In the fifth pollen zone (Ⅴ), the vegetation was represented by a steppe or tundra with a cold and dry climate at its initial stage, but in the late stage the flora was characterized by a deciduous broadleaved forest and steppe, indicating the climate was warm and less humid. Pollen zones Ⅵ–Ⅶ, the herbaceous plants, such as Artemisia, Gramineae, Chenopodiaceae etc. were predominant. The climate was rather dry and cold. The plants of the boreal conifers as Picea, ilbices, Larix, Pinus and the subpolor plants such as Betula were thriving in the low land and plain on the last glacial stage demonstrating that time the climate was humid and cold. Judging from the pollen analyses of core QH70, the vegetational development and climatic changes in Fulaerji had been rapid since the Late Tertiary. It is more or less significance to use pollen analysis in hydrogeology and engineering geology.     

L’industrie lithique du site Pléistocène inférieur de Pirro Nord (Apricena, Italie du sud) : une occupation humaine entre 1,3 et 1,7 Ma

The site of Pirro Nord (also known as Cava Pirro or Cava Dell’Erba) is known in literature since the 1970's of the last century as a palaeontological site, of which the mammalian fossil association constitutes a reference (local) fauna for the European latest Villafranchian. This fossil association is also known for the occurrence of some African elements. During the 2005, a lithic industry has been found in three karst fissures, together with the typical elements of the Pirro Nord vertebrate assemblage. The biochronological assessment based on the vertebrate assemblage attributes it to a time interval bracketed between 1.3 Ma and 1.7 Ma. Thus the site of Pirro Nord represents the oldest human occupation of Europe so far known. The lithic assemblage, attributable to the Mode 1, is constituted by three cores and seven flakes, and is made only on flint. Lithic artefacts have been found in stratigraphic context during the preliminary surveys of the three fissures, that they will be the object of systematic excavations in the years to come.     

Lentic Basommatophora molluscs and hygrophilous land snails as indicators of habitat and climate in the Early-Middle Pleistocene (0.78 Ma) at the site of Gesher Benot Ya‘aqov (GBY), Israel

The lentic Basommatophora molluscs and hygrophilous land snails of the Early-Middle Pleistocene site of Gesher Benot Ya‘aqov (GBY), 0.78 Ma, crossed by the Matuyama-Brunhes chron boundary [MBB] were studied in order to reconstruct their specific habitats and possible reactions to climate change along the site sequence. Samples of equal sizes from 27 of the 46 layers along the 100 k.yr. time-span of the site were examined. About 2000 specimens of 21 lentic and hygrophilous species belonging to five families: Planorbidae (11), Lymnaeidae (6), Acroloxidae (2), Carychiidae (1) and Succineidae (1) were identified. The family with the largest biodiversity is the Planorbidae and of these, the most abundant species include Gyraulus piscinarum (937), Planorbarius corneus (210) and Radix labiata (160). The recent known zoogeographic origin of 81% of the species is Palaearctic and Holarctic.The MBB coincides with remarkable environmental changes reflected in molluscs, other faunal and floral elements and stable isotopes. The Planorbidae and Lymnaeidae reach greater abundance (90% and 80% of their assemblages, respectively) pre-MBB, while Acroloxidae, Succineidae and Carychiidae are more abundant (74%, 64% and 90%) post-MBB.Our data indicate that GBY molluscs show a two-phase pattern (shallow and deep lake) in each of the five defined cycles. Their numbers increase during the shallow water phases, thus the site climate changes from cold and humid in the oldest layers, to dry and cold up to the MBB and few succeeding layers. Between cycles 2 and 3, post-MBB, we see a short period of warm and humid climate that enables the influx of African and Asian elements. At the same time, cold climate species of Euro-Siberian and Palaearctic origin disappear. The succeeding layers indicate a cooler and humid climate. Finally, the sequence indicates deep water in the oldest layers and desiccation towards MBB and deeper water post-MBB.     

Monsoon versus uplift in southwestern China--Late Pliocene climate in Yuanmou Basin, Yunnan

Yuanmou Basin of Yunnan, SW China, is a famous locality with hominids, hominoids, mammals and plant fossils. Based on the published megaflora and palynoflora data from Yuanmou Basin, the climate of Late Pliocene is reconstructed using the Coexistence Approach. The results indicate a warm and humid subtropical climate with a mean annual temperature of ca. 16-17°C and a mean annual precipitation of ca. 1500-1600 mm in the Late Pliocene rather than a dry, hot climate today, which may be due to the local tectonic change and gradual intensification of India monsoon. The comparison of Late Pliocene climate in Eryuan, Yangyi, Longling, and Yuanmou Basin of Yunnan Province suggests that the mean annual temperatures generally show a latitudinal gradient and fit well with their geographic position, while the mean annual precipitations seem to be related to the different geometries of the valleys under the same monsoon system.     

Comportements de subsistance au Paléolithique supérieur en Crimée : analyse archéozoologique des couches 6-2, 6-1 et 5-2 de Buran-Kaya III

The rockshelter of Buran-Kaya III (Crimea), found in 1990 by A. Yanevich, presents an exceptional stratigraphic sequence ranging from the Middle Palaeolithic to the Neolithic. The cultural layers yielded abundant assemblages of lithic and bone industries, personal adornments and mobiliary art, several ones made of mammoth ivory. We present here the results of zooarchaeological analyses of the large mammal remains from layers 6-2, 6-1 and 5-2, attributed to Gravettian sensu lato, and their interpretation in terms of subsistence behaviours, by comparing the three assemblages. The faunal composition of the three layers is rather homogeneous. The site settlements seem mainly related to the acquisition and treatment activities of small and middle-sized mammals, especially saiga antelope in summer, and large-sized mammals, in winter in 6-1 and maybe also in 5-2. During Gravettian, Buran-Kaya III was repeatedly used as a butchery or short-termed camp-site, probably in summer for hunts of saiga antelope.     

Les néandertaliens de la Caverna delle Fate (Finale Ligure,Italie). I - Chronostratigraphie,restes squelettiques

The new excavations derived by the French-Italian team in the Caverna delle Fate, Finale Ligure (Italy) between 1983 and 1987 have permitted the digging up neandertalian remains in a chronostratigraphic and paleoenvironmental accurate context. They increased the bones identified in the old collection of the Father Amerano's excavations. Actually 16 humain remains including frontal elements, zygomatique, occipital fragment, hemimandible, mandible and 10 isolated teeth can be attributed to one adult and one child 8–10 years old. This assemblage shows two interesting topics: these human remains have affinities with other neandertalian elements discovered in the occidental European Mediterranean area, so that we propose the existence of a gracile neandertalian population in this region; their chronological attribution to the MIS 5.1 suggests that at this stage the neandertalian apomorphies are not wholly integrated.     

宁波沿海平原Z02孔第四纪地层及古环境演变

宁波沿海平原第四纪沉积物属于海陆交互沉积,记录了良好的古气候变化信息,是研究古气候冷暖变化、沉积物沉积特征的良好载体.对位于宁波沿海平原东南部的Z02孔进行14C和古地磁测年,根据钻孔岩性、孢粉组合、有孔类和介形类组合、粒度等环境替代指标特征,确定了 Z02孔第四纪地层划分,揭示了研究区第四纪以来的古环境演变信息.结果...     

Signification paléoécologique des assemblages de diatomées du Messinien dans le bassin de Melilla-Nador (Rif Nord-Oriental, Maroc)

In the Melilla-Nador basin, the diatomites represent one of the main sedimentary components of the Messinian together with reefal carbonate platforms. Two vertical sections were realised in the diatomitic levels from distal platform. Diatom assemblages are for the first time described in this basin. A total of 125 diatom species were determined: 73 centrics and 52 pennates. Significant diatom assemblages defined from the statistical analysis indicate ecological variations concerning diatomitic levels or parts of diatomitic levels. Using the data sets we propose paleoenvironmental models showing the complexity of the ecological interactions. This study point the permanence of opened marine environment, the impulse of cold waters from Atlantic origin, a general decrease in bathymetry in the Messinian marls-diatomitic series, the influence of the carbonate platform progradation and the occurrence of upwelling systems.     

Analyse préliminaire des ensembles lithiques de Hakemi Use, site du Néolithique final dans le sud-est de la Turquie

Hakemi Use is a mound in southeastern Anatolia where rescue excavations have recently brought to light cultural remains dated to the late Neolithic from the Hassuna and Samarra periods. The lithic assemblages from this site were produced from flint and obsidian. Although flint is available locally, obsidian was imported but its sources are as yet unknown. Retouched elements are generally rare among the lithic assemblage. Most of the blades and bladelets are represented by the mesial parts of the blanks, and were obtained by unidirectional flaking. Debitage products such as core tablets and crested blades are rare. The study of the groundstone objects is still ongoing. Thus, this paper reports the results of the analysis of the knapped stone products recovered during the first and the second excavation campaigns at Hakemi Use.     

Le site des Vachons : étude de la partie gravettienne de la collection de l’IPH

This article firstly summarizes the process of study of an old collection, which had not been considered since the excavations at the site Les Vachons, started before 1914 and completed around 1939. The studied collection of J. Coiffard, both excavator and inventor of this site, includes four-fifths of the artefacts because, in 1940, he donated approximately one fifth to the Eyzies Museum. For his part, J. Bouyssonie who participated in the excavations for 3 years gave the major part of his own collection to the Archaeological Society of Charentes Angouleme where its condition makes it difficult to analyze. Despite these restrictions, based on statistical comparisons with counts many other sites, I came to the conclusion that the top three layers of Les Vachons are a confirmation of the Gravettian model, developed by B. Bosselin and F. Djindjian through their factor analysis. This model seems much better suited to the stratigraphy of Les Vachons, than all assumptions made by previous analysts in their attempt to bring the industries from the three layers in what remains from the Peyrony model.     

湖北秭归盆地中侏罗世陈家湾组孢粉组合的发现及其意义

本文首次报道了湖北秭归盆地陈家湾组孢粉组合,该组合可归入Cyathidites minor-Classopollis Callialasporites为代表的组合,时代属中侏罗世。陈家湾组孢粉组合的特征反映了秭归盆地中侏罗世泄滩组、陈家湾组和沙溪庙组三个组的孢粉组合的面貌基本一致,仅早期组合与中、晚期组合略有差别。建议以Gyathidites minor-classopollis-callialasportes组合代表湖北西部——重庆地区中侏罗世孢粉组合,早期为Lunzisporites pallidus亚组合,中晚期为Converrrcosisporites venitus亚组合。根据孢粉植物群在本区侏罗纪垂直分布情况,提出早侏罗世时期属亚热带一热带炎热潮湿气候环境,植物生长茂盛;早侏罗世之后,潮湿的气候仍占主导地位,但出现了干旱的先兆;中侏罗世早期进入了半干旱阶段,随后即为炎热干旱的气候所笼罩;至晚侏罗世达到非常干旱的程度,植物种类十份单调,唯有掌鳞杉科植物占据着统治地位。     

Les faunes d’ammonites du Pliensbachien inférieur des séries dauphinoises de la Durance (Jurassique inférieur, Barrage de Serre-Ponçon, Hautes-Alpes, France)

The Liassic ammonite faunas and especially those of the Early Pliensbachian are of major importance for the understanding of the stratigraphic framework of the “Dauphiné” zone of the southern subalpine ranges (“dôme de Remollon”). Until now, only listed by the authors, these faunas are, for the first time, described and illustrated in the present paper. With about twenty species, these faunas cover the whole of the Early Pliensbachian. There are poorly diversified and of clearly Euroboreal affinities. Nearly all of the species are abundant and common in most of the NW European fossiliferous localities. Despite of a paleogeographical location fairly close to the Alpine zones (Southern Alps and Austroalpine units) with rather diversified faunas of mainly Mediterranean affinities, none Mediterranean taxa are present in the studied area. Unfortunately, the current stratigraphic and paleogeographic knowledge do not allow to ascertain if this reflects a separation due to paleoenvironmental or true paleogeographic barriers. In this latter case, the general geologic implications would be remarkable.     

Analyse des artefacts lithiques du site de Longgupo

Excavation has enabled recovery of 854 artifacts within 30 archaeological levels in the south sector and 11 in the north (chapter 3). These levels are quite probably contemporaneous, or even the same. The quantitative disparity in the number of strata between the two sectors is simply due to the fact that only the lower half of the northern zone was completely investigated. Similarly, the number of artifacts recovered by level varies according to the surface area excavated, although is some cases the density of material is significant despite the small area excavated, for example stratum C IV 5 which contains 174 lithic artifacts in 2 m². Before undertaking the technological analysis of the artifacts, given the preceding polemics provoked by the great age of this site and its implications for the spread of the first populations out of Africa, it was deemed important to carry out a plurifactorial analysis combining all of the data related to: the stratigraphy, taphonomic processes (post-depositional disturbance), analysis of natural processes that may have produced eoliths, experimentation and techno-functional analysis of the material. The stratigraphy shows clear interstratifications of fine and coarse fluviatile levels with often very clear particle size sorting of the coarse fraction. The archaeological material is typically found at the interface of these strata, either at the base of a clayey matrix, overlying a preceding coarse level, or in the superficial part of a sandy-clay deposit underlying coarse deposits. Post-depositional disturbance revealed during the new excavations in 2003–2006 cannot alone be the cause of eoliths. Excavation of a 6 m² zone in the modern river bed, located below the site, has demonstrated that the technological traits of eoliths recovered cannot in any way be confused with the technological traits of the artifacts recovered at the site itself. Similarly, viewed quantitatively, the 6 m² zone excavated in the river bed yielded around 20 eoliths while the 30 m² zone excavated at the site yielded 854 artifacts, one stratum alone yielding 184 artifacts in a 3 m² zone. During the experimental phase, adopting the same conditions of procuring raw material, from the same river bed, we very quickly realized the rarity of types of adequate volume that had been generally used at the site and the need to use certain operational processes to create such a form. In addition, the hardness and presence of several natural fracture planes in the Triassic limestone explain the choice of different operational processes and the very high number of knapping accidents, including those occurring during bipolar percussion. Although 90% of the raw material used was cobbles or broken blocks of local Triassic limestone, 10% of the tools were made on exogenous raw materials – siliceous or gravelly limestone, quartzitic sandstone, chert, volcanic rock – that are absent from the immediate environment of the site. These raw materials were brought to the site in the form of tools: worked cobbles, large retouched flakes, backed double-truncated flakes, a plaquette with a lateral bifacial edge, etc. The 854 artifacts have been classified into six object classes: worked cobbles with transversal edge (39%), worked cobbles with lateral edge (2%), unipolar flakes (27%), bipolar objects (half-blocks, half-cobbles including some flat “split” cobbles, “orange slices”, flakes and diverse fragments) (17%) and fragments resulting from knapping of blocks or cobbles (13%), hammerstone (2%). When the frequencies of these classes are calculated for each of the sectors, percentages are similar, indicating a high degree of homogeneity in the archaeological assemblages at the site. The situation is somewhat different when assemblages are compared within a single sector. Slight differences appear in the percentages of bipolar pieces and unipolar flakes. These differences seem to be random, like the frequency rate of knapping accidents in bipolar reduction, or economic, such as the choice of operational schemes to create worked cobbles based on the availability of suitable raw materials. The technological affinity between each of the archaeological assemblages tends to demonstrate great stability in technological knowledge through time. The class of worked cobbles is by far the most important and, apart from a few flakes produced intentionally, it appears to group all of the tools. To avoid placing these tools in a restrictive, semantically meaningless, class, we prefer the concept of matrix to the term worked cobble. A matrix is a structured arrangement of a series of technological traits, in a form as close as possible to that of the future tool. The matrix phase leads to the tool production phase, which may be unnecessary if the matrix phase includes fictionalization. In other words, the concept of matrix enables separating the phase of preparing a predetermined volume, such as a blade, Levallois flake or bifacial piece, from the tool production phase, consisting in creating the type of transformative edge intended, if necessary. The tool is thus an artifact of a specific form with an integrated edge and an operational scheme both specific to the function attributed to it and means of use associated with the form. Observed variability relates to: the size of the volume ranging from to 20, morphology, the form of the line formed by the edge which can in frontal view be curved, linear, sinuous or denticulated, and in transversal view curved, linear, sinuous or saw-toothed, and the length of the edge ranging from 1 to 10. Matrices with a simple bevel are distinguished from double bevels. In the framework of the technological analysis of production schemes to produce matrices with a simple bevel, a broad range of variability in production schemes can be observed, divided arbitrarily into two stages. The first stage consists in creating as closely as possibly the technological traits of the future matrix due to five general schemes. The first scheme (A) consists in selecting a cobble or block naturally possessing at least some of the technological traits needed. The missing traits are added by various preparations, including bipolar percussion 3 times out of 5. The second scheme (B) consists in knapping a flake from the block with some of the technological traits required for the matrix present on one of its surfaces. The third scheme (C) consists in the choice of a plaquette from which a bipolar shock creates the main traits of the matrix. The fourth scheme (D) consists in choosing a volume very similar to the intended matrix. The fifth and final scheme (E) consists in knapping a flake with technological traits very different from those intended. Depending on the distance between intention and realization, a second stage may be necessary. In general, this second stage perfects or creates the intended active edge, which is rarely obtained in the first stage. To produce a matrix with a double bevel, it is sometimes necessary to add an intermediate stage in order to prepare the second bevel. The first stage remains the same, with the use of the five operational schemes. By contrast, a clear difference exists in the percentages for the use of these schemes. For a matrix with a simple bevel, scheme A is dominant, followed by scheme D, while the situation is reversed for a matrix with a double bevel, where scheme D is dominant. Unipolar flakes, representing 27% of the assemblage, are produced in three different ways. The most important is flakes resulting from matrix production. The two others are flakes produced during different knapping schemes, some flakes in relation to the few cores present, other flakes in exogenous raw materials produced elsewhere and generally much larger. The other classes are dominated by bipolar products resulting essentially from knapping accidents. To summarize, these assemblages are characterized by: the search for tools differentiated by form and active edges; more than 90% of the tools made on two kinds of supports: a matrix with a simple bevel or a double bevel; matrices obtained using different operational schemes successively associating if necessary a knapping stage and a shaping stage. While the Triassic limestone is hard and thus imposes a strong constraint on knapping, the range of operational schemes appears to have been a “cultural” response diversified to this constraint and the presence of tools on exogenous raw materials. At the scale of China, comparison of this industry is impossible since it is the only site of this age and to contain so much material. The site of Majuangou, the only site of similar caliber, is younger by several hundred thousand years and is located several thousand kilometers to the north, making comparisons meaningless. We note only that most of the tool supports at Majuangou are knapped flakes. On an inter-continental scale, the comparison of sites of equal age is more promising. But lithic analyses are based on different methods, preventing comparison of similar data. However, if we make a simple summary of the data available, we can first say that in Africa, during these periods, different development technological stages were present and stages that are considered more evolved are manifestly less common using our approach. While these stages are more or less contemporaneous, which counters the idea of uniqueness, they would more surely be evidence of populations that were not in direct contact and had separate lines of development. In Asia, the Longgupo industry evidences a different technological option than that of contemporaneous populations in Africa. By contrast, when we take into account its developmental stage, we realize that this is an “evolved” stage in which the form of the support of the future tool is predominant. If we compare Africa and Asia in terms of stages, we are a priori at the same stage with different options being selected.     

Pteropods as climatic indicators in quaternary sequences: A Lower-Middle Pleistocene sequence outcropping in Cava Puleo (Ficarazzi,Palermo, Italy)

Pteropod assemblages from a section outcropping at Cava Puleo (Ficarazzi, Palermo, type locality of the Sicilian stage) were studied for a paleoclimatic interpretation. The studied section directly overlies the subsurface Lower Pleistocene sequence.A curve of the absolute abundance of the subarctic species Limacina retroversa in the pteropod assemblage and a climatic curve based on the total amount of cumulative percentages of cold and warm pteropod indicators are proposed; the former shows a climatic trend in which a strong cold peak can be easily inferred at the top of the proposed Sicilian stratotype section. This drastic cold event is the first one recognizable in the local Lower Pleistocene sequence and may be correlated with the cold event recognized by Shackleton and Opdyke (1976) at the top of stage 22. The cold climatic fluctuation was abruptly followed by an internal with warm-temperate climate characterized by a tropical—subtropical assemblage.     

Découverte de charophytes de l’Albien dans la Formation Kebar (Tunisie centrale) : implications paléoécologiques et paléobiogéographiques

In Tunisia, in the platform domain, the Aptian-Albian transition is associated with a major stratigraphic gap not precisely dated, which is related to the subaerial exposure of the Aptian Orbata platform. Locally, in central Tunisia (Jebel Kebar), this gap is substituted by the sedimentary records of the Kebar Formation. This formation provided a rich association of fossil charophytes, formed by Atopochara trivolvis trivolvis, Clavator harrisii zavialensis and Sphaerochara verticillata which allows attributing it to the late Aptian–early Albian interval (most probably early Albian). In addition, a new variety, Sphaerochara verticillata var. kebariensis, is described. The charophyte assemblage shows significant biogeographic affinities with a coeval flora found in the Iberian Peninsula. The Kebar Formation was previously regarded as exclusively nonmarine, but the presence of the assemblage of charophytes and associated ostracods described rather indicates a fluctuation between margino-littoral (lagoonal) and continental environments.