Les premières sociétés aziliennes : nouvelle lecture de la genèse du phénomène d’azilianisation dans les Alpes du Nord à partir des deux niveaux d’occupation de l’abri de La Fru (Saint-Christophe-la-Grotte, Savoie)

摘要

The origin of the Azilian traditions caused much debate over the past decade, in particular in northern France. The analysis of lithic industries played a central role in these debates. A revision of the early Azilian deposits from La Fru (Saint-Christophe-la-Grotte, Savoie) will allow us to propose a new interpretation of this techno-complex outside the Paris Basin and to discuss the genesis of the ‘ Azilianisation’ process in this context. The shelter at La Fru is currently one of the richest deposits known for the end of the Upper Palaeolithic in western Europe. It has yielded occupation levels from the Upper Magdalenian (17000 cal. BC) to the Middle Mesolithic (9000-8200 cal. BC) within three separate excavation areas (areas 1, 2, 3). The early Azilian occupations are located in area 1 (layer 3) and area 2 (layer 3). The numerous and reliable dates show that settlement of the site by early Azilians occurred between 12300 and 11300 cal. BC. Unfortunately, the lack of environmental data from the site does not allow the early Azilian settlements to be related to a chrono-environmental phase. The lithic industries from La Fru and especially layer 3 area 1, have already been the subject of numerous studies. However, they were never evaluated from a taphonomic and techno-economical perspective, although it is the combination of these analytical methods which will allow these karstic contexts to be integrated into a discussion on the evolution of Lateglacial societies on a European scale. Our aim is, first, to describe the contents of each early Azilian collection from La Fru, using modern analytical methods. In a second step it will be possible to compare our results with the best documented early Azilian collections (Le Closeau, Bois Ragot, etc.). Finally, we will propose a new reading of the early Azilian tradition in the context of the French Alps. The first step consisted of an archaeo-stratigraphic analysis of the archaeological sequences available. It allowed the different degrees of disturbance in each archaeological layer to be highlighted. For area 1, layer 3 is the result of a palimpsest of settlements from the early and recent Azilian. Therefore, the lithic industry is clearly the result of several occupations. Area 2, and layer 3 in particular, have been less affected by post-depositional disturbance. However a Magdalenian component was identified. The comparative technological analysis helped to highlight the similarities and differences between the two collections. The aim of the productions is similar in both collections. The first step of the ‘ chaîne opératoire’ consisted of the production of blades from 70 to 100 mm in length. These blades were transformed into common tools (burin, end-scraper, retouched blades). The technical processes are also the same between the two collections. We note that the most regular blades from area 1 were used as supports for burins, whereas for area 2 they were used as blanks for end-scrapers. The shorter blades (≤ 60 mm), produced in the second stage of the ‘chaîne opératoire’, served as supports for the manufacture of backed points. In both collections they were based on regular blanks. However, we can note the presence of two distinct types of backed points (bipoints and monopoints). This is a characteristic shared with layer 4 of Bois-Ragot (Vienne). At La Fru, this coexistence of two types of backed points during the early phase of the Azilian is seen as having an economic origin : the shorter blades, probably produced in the final stages of knapping, were transformed into monopoints, the longest into bipoints. From a typological or technological point of view, the early Azilian lithic industry from La Fru shows similarities with contemporary or sub-contemporary settlements from the Pyrenees to the north of the Paris Basin. While in certain geographic areas such as the Paris Basin backed points appear in the lithic toolkit of the Magdalenian populations, it is not the case in the northern Alps. Thus, these geographic sectors may have played a role as an epicentre for the spread of new technical practices. The almost synchronous appearance of the early Azilian leaves little doubt as to the global nature of the process presiding over these transformations. Can a ‘ case-by-case’ process of ‘Azilianisation’ still be envisaged in each regional Magdalenian substratum ? In view of the strong similarity noted in the lithic industries and the practices of these groups it seems practically certain that these changes in tradition spread from an epicentre which lastingly transformed Magdalenian societies. Exchange or circulation networks, evoked with regard to the Upper Magdalenian, do not contradict the hypothesis of a rapid spread of these new ideas. Did they arise in contexts where adaptation to changes in the environment (animals and plants) called for rapid and radical reaction by the Magdalenians, before spreading to neighbouring territories ? That is a hypothesis which seems to us to be perfectly coherent with our present state of knowledge.