Vulcanism and Prehistory in the massif central of France : Future Prospects for Sustainable Development of Rural Highlands

If recent huge projects in Auvergne, as Vulcania near Clermont-Ferrand for example, try to use vulcanism as a matter of sustainable local development, attracting either seasonal touristic flow or all-year academic activities, the remote highlands of Velay begin to discover that archaeology and vulcanism make an original combination to increase interest of populations and can be a key for sustainable rural development.volcanisme;archéologie;développement local;développement durable;Massif central;Haute-Loire

Polignac – Les Costes, Grotte de Sainte-Anne I

Identifiant de l'opération archéologique : 116 Date de l'opération : 2007 (FP) Seul site stratifié répertorié du stade isotopique 6 en région Auvergne, la grotte de Sainte-Anne I est connue pour ses outillages du Paléolithique moyen ancien majoritairement façonnés en roches volcaniques (BSR 1993, p. 46 ; BSR 1994, p. 54 ; BSR 1995, p. 45-46 ; BSR 1996, p. 41-43 ; BSR 1997, p. 46 ; BSR 2006, p. 65-67, Jean-Paul Raynal). C’est une petite cavité d’une cinquantaine de mètres carrés accessibles ou..

Les retombées volcaniques distales de la Chaîne des Puys

pdf du manuscrit. Contacter l'auteur pour une version illustrée.Reconnaissance des éruptions de la Chaîne des Puys par l'étude des retombées distales de cendres volcaniques enregistrées dans les dépôts de la plaine de Limagne

Hommes et volcans en Basse Auvergne préhistorique

pdf du manuscritNational audienceFrom 160 to 30 ka BP, Western Limagne is strongly affected by local explosive vulcanism, lava flows and distal tephra falls from the old Chaîne des Puys. Fromm the Older Dryas to the Atlantic Period, ten pyroclastic formations originating from trachyandesitic and trachytic eruptions covered the plain of the Limagne d'Auvergne and have been preserved in various depositional contexts. They are useful isochronic markers for archaeologists examining their impact on prehistoric behaviours and settlements.De 160 à 30 ka BP, la Limagne occidentale est le siège d'un volcanisme parfois violemment explosif et soumise aux effets secondaires des éruptions de la phase ancienne de la Chaîne des Puys. De 12 à 6 ka BP, dix recouvrements de téphras, suffisamment importants pour avoir été préservés en stratigraphie dans des environnements sédimentaires divers, ont affecté la Limagne. Ils caractérisent des éruptions pour l'essentiel à magmas trachyandésitiques et trachytiques et sont de bons marqueurs isochroniques. L'homme préhistorique a subi ce volcanisme qui a profondément transformé son cadre de vie

: The Les Roches Tephra : a marker of volcanism contemporary with the Late Mag-dalenian in the Massif Central, France

pdf du manuscritNational audienceThe Les Roches tephra has been defined at Gimeaux. It was emitted by a trachyandesitic volcano (Puy de la Nugère ?) at the end of Dryas II, around 12000 BP. It as directly affected a late Magdalenian living site , Abri Durif at Enval, 30 km to the southeast of its source.Définie à Gimeaux, la Tephra des Roches, de composition entre trachyandésite et trachyandésite basaltique, a été émise par un appareil septentrional de la Chaîne des Puys (Puy de la Nugère ?) à la fin du Dryas II, vers 12 000 BP. Elle a directement affecté la dernière occupation madgalénienne de l'Abri Durif à Enval, 30 km au Sud-Est de son point d'émission supposé

Un cadre téphrostratigraphique réactualisé pour la préhistoire tardiglaciaire et holocène de Limagne (Massif central, France)

pdf du manuscrit avant révisionNational audienceFrom the Older Dryas to the Atlantic Period, ten pyroclastic formations originating from trachyandesitic and trachytic eruptions covered the plain of the Limagne d'Auvergne and have been preserved in various depositional contexts. They are useful isochronic markers for archaeologists examining their impact on prehistoric behaviours and settlements.Dix recouvrements de tephras, suffisamment importants pour avoir ete préservés en stratigraphie dans des environnements sédimentaires divers, ont affecté la Limagne du Dryas ancien à l'Atlantique. Ils caractérisent des éruptions pour l'essentiel à magmas trachyandésitiques et trachytiques. Outre leur rôle incontestable de marqueurs isochroniques, ils incitent à reconsidérer l'impact du volcanisme de la Chaîne des Puys sur l'environnement des peuplements préhistoriques contemporains

L’espace minéral au Paléolithique moyen dans les départements du Cantal, de la Haute-Loire et du Puy-de-Dôme

Date de l'opération : 2006 (PT) Les travaux se sont déroulés de juillet à la fin novembre 2006 dans les départements de la Haute-Loire, du Cantal et du Puy-de-Dôme et ont été complétés par des travaux dans l’Allier, suite aux prospections antérieures de l’un d’entre nous (Maurice Piboule). Notre démarche n’est pas un simple complément aux nombreuses études régionales consacrées au silex depuis Vinay en 1867 : aucune démarche antérieure n’a en effet utilisé une méthodologie minéralogique et pé..

Volcanic markers in coarse alluvium at Melka Kunture (Upper Awash, Ethiopia)

autorisation des éditeurs de l'ouvrage par email du 01/07/05The knowledge we have today of the different volcanic episodes which occurred over the last several million years in the environment of the Melka Kunture prehistoric sites allows a new appraisal of the nature and abundance of emitted lavas that are represented in the alluviums of the Awash River and its tributaries. Moreover, the most compact facies can also be seen in the different archaeological sites. Several alluvial units and some archaeological layers have been sampled and petrographic counts performed on the basis of mainly macroscopic and some microscopic determinations of the lavas. They allow comparisons between samples and offer a better understanding of local available raw materials for use by hominids

Garba IV and the Melka Kunture Formation. A preliminary lithostratigraphic approach

autorisation des éditeurs de l'ouvrage par email du 01/07/05The lithostratigraphic analysis of the different sections at Garba and Gombore clarify the dynamics nature of the deposition processes for the lower part of the Melka Kunture Formation. Downstream transport and accumulation are prevalent during sedimentation processes. Channel lag petrographic suites reflect the basin geology and indicate a period of global dismantling of ancient volcanic relief and important lateral contributions from both banks' tributaries to alluvial processes. Volcanic activity is the main provider for fine grains sediments: pumice derived from pyroclastites of penecontemporaneous plinian eruptions contribute massively to channel lags and to major accretion events (Sl, Sp, St facies), reworked coarse tuffs form massive beds (Sm facies) while cinereous tephras are responsible for silts deposition (Fsm, Fm facies). Resistant and opaque minerals form the matrix of bed lags and most of the sandy bases of current structures. Grain-size distribution also reflects the evolution of channels. At Gombore, six channels are superposed and partly embedded. Each of them exhibits a logical facies succession leading to complete infilling and abandonment while the main stream migrates towards SE. Archaeological layers are systematically associated with the bedforms, except for the uppermost one. The volcanic input is responsible for overloading of streams and forces channel changes. Facies previously considered as lacustrine are actually fluvial facies. The “major cut-and-fill” previously considered as major erosion phases by Chavaillon (1973) are only simple channeling processes. At Garba IV, three channels are superposed and partly embedded. Each of them exhibits a logical facies succession leading to a complete infilling and eventual abandonment. Archaeological layers are associated with the bedforms, local erosional surface or temporary abandoned channel. The volcanic input is systematically responsible for over-loading and forces channeling. Here again, facies previously considered as lacustrine are actually fluvial and the “major cut-and-fill” previously considered as important erosional phases are only simple channeling processes. Considering the paleomagnetic data and especially the brief normal polarity event recognized both at Garba in the upper part of “Tuff A” and at Gombore Ig at the top of sands above the archaeological layer (Cressier 1980), the preliminary absolute dating (Schmitt et. al. 1977) and the revisited tuff correlations, it can be concluded that both series deposited between 1.77 Ma (end of Oldoway Polarity Subzone) and 0.78 Ma (Brunhes-Matuyama limit) at most. From an archaeological perspective, Oldowan and Acheulian sites are associated with bedforms and gravel bars. These layers have been affected by currents (sieve effect, re-orientation of large pieces) and repeatedly washed and covered by abrasive sands during accretion or subjected to erosional episodes which have highly disturbed the primary organisation of artefacts. The superposition of the different facies clearly indicates a tectonic control of the sedimentation for the Melka Kunture Formation (at least for its lower terms described in this paper) during the Lower Pleistocene: the recurrent faulting (moderate subsidence of the semi-graben) along the Melka scarp which borders the Garba-Gombore area is directly responsible for this architecture. A pause in subsidence combined with head erosion through the Melka Kunture raised block allowed a return to valley incision processes and installation of valley-plain and stepped terraces fossilized by the non-welded ignimbrite episode, significantly wide-spread and thus named Kella Formation.This unit belongs clearly to the Matuyama Polarity Zone with a minimum age of 0.78 Ma. The setting of this ignimbrite seems to have fit into a topography close to the present one. After the emplacement of the non-welded ignimbrites a fault reactivation takes place with an important displacement. The meandering of the palaeo-Awash was certainly determined by the obstacle of the raised block of Melka Kunture according to the Main Ethiopian Rift evolution (see Bardin et al. in this volume). Combined head erosion and subsident faulting are responsible for the successive changes in sedimentation style such as channeling, superposition or down-cutting when volcanic input increases deposition rates and forces channeling changes. The different facies identified indicate a shallow, seasonal, low-sinuosity, braided river environment. This is indicative of a well-contrasted dry-wet seasonal climate

: Recognition of the Campanian Ignimbrite near the Gulf of Policastro (Basilicata, Italy), 150 km from the eruptive vent. Vulcanological and palaeoenvironmental implications

pdf du manuscritNational audiencePyroclastites whose facies and chemical composition are congruent with those described for the Campanian Ignimbrite have been recognised close to the Gulf of Policastro, 150 km south east of Naples. This doubles the extent in that direction hitherto known for this igneous event which appears of greater magnitude than previously hypothesisedLa reconnaissance de pyroclastites de faciès et de composition chimique caractéristiques de l'ignimbrite campanienne à 150 km de Naples, près du golfe de Policastro, double l'extension jusqu'alors établie vers le Sud-Est sur le continent pour cette éruption préhistorique majeure dont la magnitude est sans doute plus importante qu'on ne le supposait