POTENTIAL USE OF THE E' CENTER AS AN INDICATOR OF INITIAL RESETTING IN TL/ESR DATING OF VOLCANIC MATERIALS

International audienceQuartz inclusions embedded in volcanic materials can be used for dattng Quaternary volcanoes by TL or ESR methods. For these techniques the initial zeroing by heat is assumed. However, this assumption can sometimes be questioned either because the temperature was not high, like in phreatomagmatic deposits, or because of contamination, like in thin tephra layers. Preliminary observations suggested that the présence of thé E' center could be an indicator of poor initial zeroing. This possibility was investigated in the present work. Quartz grains from various geological contexts were studied for comparison. Annealing and régénération of the E' center was explored

Across the Gap: Geochronological and Sedimentological Analyses from the Late Pleistocene-Holocene Sequence of Goda Buticha, Southeastern Ethiopia

Goda Buticha is a cave site near Dire Dawa in southeastern Ethiopia that contains an archaeological sequence sampling the late Pleistocene and Holocene of the region. The sedimentary sequence displays complex cultural, chronological and sedimentological histories that seem incongruent with one another. A first set of radiocarbon ages suggested a long sedimentological gap from the end of Marine Isotopic Stage (MIS) 3 to the mid-Holocene. Macroscopic observations suggest that the main sedimentological change does not coincide with the chronostratigraphic hiatus. The cultural sequence shows technological continuity with a late persistence of artifacts that are usually attributed to the Middle Stone Age into the younger parts of the stratigraphic sequence, yet become increasingly associated with lithic artifacts typically related to the Later Stone Age. While not a unique case, this combination of features is unusual in the Horn of Africa. In order to evaluate the possible implications of these observations, sedimentological analyses combined with optically stimulated luminescence (OSL) were conducted. The OSL data now extend the radiocarbon chronology up to 63 ± 7 ka; they also confirm the existence of the chronological gap between 24.8 ± 2.6 ka and 7.5 ± 0.3 ka. The sedimentological analyses suggest that the origin and mode of deposition were largely similar throughout the whole sequence, although the anthropic and faunal activities increased in the younger levels. Regional climatic records are used to support the sedimentological observations and interpretations. We discuss the implications of the sedimentological and dating analyses for understanding cultural processes in the region.This research benefited from funding of the National Geographic Society (http:// nationalgeographic.org/), grants # 8110-06 and 8510-08 (ZA), of the Wenner-Gren Foundation (http://www.wennergren.org/), grant # ICRG e 102, (ZA and DP), of the Hebrew University of Jerusalem (http://new.huji.ac.il/en) (EH), of the French National Research Agency (http://www.agence-nationale-recherche.fr), projects # ANR-09- JCJC-0123-01 (CT), # ANR-14-CE31-0023-03, and # ANR-10-LABX-52, of the Regional Priority Program « Heritage, Resources, Governance » (HEREGO, coordinated by the Institut de Recherche pour le Developpement) (DP), the Doctoral School of the Museum National d’Histoire Naturelle in Paris (France) and UMR CNRS 7194 (AL), the Smithsonian NMNH small grants, and the European Union’s Horizon 2020 research and innovation program under the Marie SklodowskaCurie grant (https://ec.europa.eu/programmes/ horizon2020/en/h2020-section/marie-sklodowskacurie-actions), agreement #655459. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript

Across the Gap: Geochronological and Sedimentological Analyses from the Late Pleistocene-Holocene Sequence of Goda Buticha, Southeastern Ethiopia

Goda Buticha is a cave site near Dire Dawa in southeastern Ethiopia that contains an archaeological sequence sampling the late Pleistocene and Holocene of the region. The sedimentary sequence displays complex cultural, chronological and sedimentological histories that seem incongruent with one another. A first set of radiocarbon ages suggested a long sedimentological gap from the end of Marine Isotopic Stage (MIS) 3 to the mid-Holocene. Macroscopic observations suggest that the main sedimentological change does not coincide with the chronostratigraphic hiatus. The cultural sequence shows technological continuity with a late persistence of artifacts that are usually attributed to the Middle Stone Age into the younger parts of the stratigraphic sequence, yet become increasingly associated with lithic artifacts typically related to the Later Stone Age. While not a unique case, this combination of features is unusual in the Horn of Africa. In order to evaluate the possible implications of these observations, sedimentological analyses combined with optically stimulated luminescence (OSL) were conducted. The OSL data now extend the radiocarbon chronology up to 63 ± 7 ka; they also confirm the existence of the chronological gap between 24.8 ± 2.6 ka and 7.5 ± 0.3 ka. The sedimentological analyses suggest that the origin and mode of deposition were largely similar throughout the whole sequence, although the anthropic and faunal activities increased in the younger levels. Regional climatic records are used to support the sedimentological observations and interpretations. We discuss the implications of the sedimentological and dating analyses for understanding cultural processes in the region.This research benefited from funding of the National Geographic Society (http:// nationalgeographic.org/), grants # 8110-06 and 8510-08 (ZA), of the Wenner-Gren Foundation (http://www.wennergren.org/), grant # ICRG e 102, (ZA and DP), of the Hebrew University of Jerusalem (http://new.huji.ac.il/en) (EH), of the French National Research Agency (http://www.agence-nationale-recherche.fr), projects # ANR-09- JCJC-0123-01 (CT), # ANR-14-CE31-0023-03, and # ANR-10-LABX-52, of the Regional Priority Program « Heritage, Resources, Governance » (HEREGO, coordinated by the Institut de Recherche pour le Developpement) (DP), the Doctoral School of the Museum National d’Histoire Naturelle in Paris (France) and UMR CNRS 7194 (AL), the Smithsonian NMNH small grants, and the European Union’s Horizon 2020 research and innovation program under the Marie SklodowskaCurie grant (https://ec.europa.eu/programmes/ horizon2020/en/h2020-section/marie-sklodowskacurie-actions), agreement #655459. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript

The origin of early Acheulean expansion in Europe 700 ka ago: new findings at Notarchirico (Italy)

Notarchirico (Southern Italy) has yielded the earliest evidence of Acheulean settlement in Italy and four older occupation levels have recently been unearthed, including one with bifaces, extending the roots of the Acheulean in Italy even further back in time. New 40Ar/39Ar on tephras and ESR dates on bleached quartz securely and accurately place these occupations between 695 and 670 ka (MIS 17), penecontemporaneous with the Moulin-Quignon and la Noira sites (France). These new data demonstrate a very rapid expansion of shared traditions over Western Europe during a period of highly variable climatic conditions, including interglacial and glacial episodes, between 670 and 650 (i.e., MIS17/MIS16 transition). The diversity of tools and activities observed in these three sites shows that Western Europe was populated by adaptable hominins during this time. These conclusions question the existence of refuge areas during intense glacial stages and raise questions concerning understudied migration pathways, such as the Sicilian route

The origin of early Acheulean expansion in Europe 700 ka ago: new findings at Notarchirico (Italy)

Notarchirico (Southern Italy) has yielded the earliest evidence of Acheulean settlement in Italy and four older occupation levels have recently been unearthed, including one with bifaces, extending the roots of the Acheulean in Italy even further back in time. New 40Ar/39Ar on tephras and ESR dates on bleached quartz securely and accurately place these occupations between 695 and 670 ka (MIS 17), penecontemporaneous with the Moulin-Quignon and la Noira sites (France). These new data demonstrate a very rapid expansion of shared traditions over Western Europe during a period of highly variable climatic conditions, including interglacial and glacial episodes, between 670 and 650 (i.e., MIS17/MIS16 transition). The diversity of tools and activities observed in these three sites shows that Western Europe was populated by adaptable hominins during this time. These conclusions question the existence of refuge areas during intense glacial stages and raise questions concerning understudied migration pathways, such as the Sicilian route

L’insediamento a bifacciali di Guado San Nicola (Monteroduni, Molise, Italia)

La monografia rappresenta un compendio di lavori specialistici sul sito paleolitico di Guado San Nicola a Monteroduni (Molise, Italia), oggetto di ricerche sistematiche ed indagini interdisciplinari inaugurate nell’area a partire dal 2000 dall'Università degli Studi di Ferrara. Il sito, ascrivibile al MIS 10/11, costituisce un tassello importante nell’ambito della ricostruzione del quadro del popolamento umano della penisola italiana e dell’intero bacino del Mediterraneo, alla luce delle considerazioni crono-stratigrafiche, della ricchezza della documentazione e della presenza di elementi innovativi dal punto di vista culturale quali la padronanza del metodo Levallois e l’uso di percussori in palchi di cervo

High resolution δ18O seasonality record in a French Eemian tufa stromatolite (Caours, Somme Basin)

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Datation par résonance de spin électronique (ESR) de carbonates et d'émail dentaire quaternaires : potentiel et problèmes

Historically, man has sought to date the major events in the history of the Earth. Initial estimates of the age of the planet and the date of the appearance of man are given in sacred books, some dating back several millennia. However, the values ​​given in these works generally minimize the duration of geological time; and the chronology established in the mid seventeenth century by Bishop Ussher from the Bible is the creation of the Earth 4004 years before the birth of Christ. This dating, far below the reality as we know today, prevailed in Europe until the eighteenth century among scientists such as Cuvier.Depuis toujours, l'homme a cherché à dater les grands événements de l'histoire de la Terre. Les premières estimations de l'âge de la planète et de la date de l'apparition de l'homme sont données dans des livres sacrés, dont certains datent de plusieurs millénaires. Cependant, les valeurs données dans ces ouvrages minimisent généralement la durée des temps géologiques ; ainsi, la chronologie établie au milieu du XVIIème siècle par l'évêque Ussher à partir de la Bible situe la création de la Terre 4 004 ans avant la naissance du Christ. Cette datation, que l'on sait être aujourd'hui très en dessous de la réalité, a prévalu en Europe jusqu'au XVIIIème siècle environ et des scientifiques tels que Cuvier s'y tenaient. Par la suite, avec les premiers travaux de stratigraphie et de géologie historique, commencèrent à apparaître les rudiments d'une échelle chronostratigraphique globale, basée en grande partie sur l'étude des assemblages de fossiles marins. A la fin du XIXème siècle, après la découverte des premiers restes d'hominidés fossiles, quatre grandes ères géologiques furent distinguées. Parmi celles-ci, l'ère Quaternaire était caractérisée par une faune identique à la faune actuelle et par la présence de l'homme. L'élaboration d'une échelle chronostratigraphique de l'ère Quaternaire a posé et pose un certain nombre de problèmes. En raison de sa courte durée, il est en effet difficile de baser la stratigraphie sur l'évolution des faunes marines, comme c'est le cas pour les autres périodes géologiques, et les chercheurs ont donc tenté successivement pour contourner ce problème d'employer les assemblages paléontologiques continentaux, l'évolution de l'industrie lithique ou des événements géologiques ou climatiques, comme par exemple les témoignages des glaciations. Ce n'est qu'après la seconde guerre mondiale que les progrès de la physique et de la chimie ont fourni les moyens de poser les bases d'une échelle chronologique "absolue" du Quaternaire, avec en particulier le développement des études paléomagnétiques et l'utilisation des techniques de datation basées sur la radioactivité naturelle. Aujourd'hui, le préhistorien, le géographe et le géologue du Quaternaire dispose ainsi d'un certain nombre de méthodes radiométriques ou chimiques, qui sont chacune caractérisées par un domaine d'utilisation précis et qui ne sont applicables qu'à un certain nombre de supports spécifiques