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20 km

Figure 5.2 Cross-section of geological outcrops along a west-east transect through the central Perigord area. After Demars 1982.

20 km

Figure 5.2 Cross-section of geological outcrops along a west-east transect through the central Perigord area. After Demars 1982.

Figure 5.3 Distribution of geological sources sampled for raw material supplies in the recent raw-material provenancing studies in southwestern France. After Geneste 1985. More recently, many additional sources have been sampled, especially in the areas to the south of the Dordogne (see Turq 1989a, 1992b).

Figure 5.3 Distribution of geological sources sampled for raw material supplies in the recent raw-material provenancing studies in southwestern France. After Geneste 1985. More recently, many additional sources have been sampled, especially in the areas to the south of the Dordogne (see Turq 1989a, 1992b).

este 1985, 1989a; Turq 1989a). All these exposures consist of different forms of limestone or related deposits with a variety of either nodular or tabular flint occurring at particular stratigraphic horizons within the deposits. The second factor is the distinctive appearance of many of the individual sources of flint which occur within the different outcrops which makes attribution to particular sources relatively easy. The third is the thoroughness with which most of these outcrops have now been surveyed for potential sources of flint supplies.

The detailed prospecting of these geological formations for potential flint and chert supplies has been carried out partly by geologists (e.g. Seronie-Vivien 1972, 1987; Valensi 1960) and partly by archaeologists working specifically on the problems of Palaeolithic flint supplies (e.g. Le Tensorer 1981; Morala 1980; Gaussen 1980; Demars 1982; Rigaud 1982; Larick 1983, 1986; Geneste 1985; Turq 1988a, 1989a). Through close collaboration, these workers have now built up an extensive reference collection of samples deriving from well over 1000 different exposures of flint-bearing outcrops, covering most of the 10,000 square kilometres of the Perigord region (Fig. 5.3) - the so-called Tithotheque du Bassin d'Aquitaine', currently housed in the regional directorate of prehistoric antiquities in Bordeaux (Turq 1989a). All recent progress in flint provenancing studies in the Perigord depends on this extensive reference collection of flint sources and, hopefully, on its representative coverage of most of the raw material resources available to Palaeolithic groups.

Figure 5,4 Documented distribution of distinctive varieties of flint in the Perigord and adjacent areas. The sources represented are 1: Bergerac flint; 2 Mussidan flint; 3 Ribérac flint; 4 honey-yellow Santonian flint; 5 beige, jaspoid flint (several sources); 6 Gavaudun flint; 7 Fumel flint. After Genestel985.

Figure 5,4 Documented distribution of distinctive varieties of flint in the Perigord and adjacent areas. The sources represented are 1: Bergerac flint; 2 Mussidan flint; 3 Ribérac flint; 4 honey-yellow Santonian flint; 5 beige, jaspoid flint (several sources); 6 Gavaudun flint; 7 Fumel flint. After Genestel985.

As yet, most of the studies of flint sources in the Palaeolithic sites of this region have been based on macroscopic studies of the appearance and texture of the flint - involving such features as colour variations, surface texture, various forms of inclusions, the thickness and character of the adhering cortex, and so on (Demars 1982; Geneste 1985, 1989a; Larick 1986). More detailed analytical studies of the fossil content or trace-element composition of the samples have so far been applied to only a limited amount of material, mainly to corroborate the results of the macroscopic studies (Valensi 1960; Seronie-Vivien 1972, 1987). How far this reliance on simple macroscopic approaches should be regarded as a significant limitation is a mat ter of debate. Ultimately, all forms of raw material provenancing studies, whether based on sophisticated analytical techniques or simpler macroscopic approaches, depend on pragmatic criteria. Thus, all these approaches depend not only on a close matching of particular archaeological samples with particular geological sources but also on the ability to demonstrate that these supposedly diagnostic features of different materials are restricted to these sources. Fortunately, many of the varieties of flint documented in the Perigord region do appear to be so visually distinctive that they can be regarded, from all available field evidence, as effectively diagnostic of particular geological outcrops (Fig. 5.4). The best known examples are some of

Figure 5.5 Integrated map of raw material sources exploited from Middle Palaeolithic sites in the Perigord and adjacent areas. The sites represented are: 1 Sandougne; 2 Abri Brouillaud; 3 Le Roc; 4 Fonseigner; 5 Les Festons; 6 Coursac; 7 Le Moustier; 8 Le Dau; 9 Grotte Vaufrey; 10 Roc de Mar s al; 11 La Plane; 12 La Lizonne; 13 Ségala; 14 La Burlade; 15 Plateau Cabrol; 16 Moulin du Milieu; 17 Las Pélénos; 18 Les Ardailloux; 19 La Grave; 20 La Chapelle-aux-Saints. After Geneste 1989b.

the highly coloured and concentrically banded flint nodules from the Maestrichtian deposits of the Bergerac region, the distinctively fine-grained, blue-grey flints from the Angoumian deposits near Fumel (Lot-et-Garonne) and some of the vividly coloured jasper-like flints from the Hettangian formations on the western flanks of the Massif Central (Demars 1982; Geneste 1985; Turq 1989a). By no means all the flint outcrops in the region are so distinctive. In particular, many of the flint sources from the extensive Senonian deposits which occupy a large area of the central Dordogne region appear to be either essentially uniform over large areas or to show localized and erratic variations within a single source which make exact provenancing impossible. Fortunately, it has now been possible to identify a sufficiently large number of the most distinctive flint sources to document at least the major patterns of movement of these materials over the greater part of the Perigord region.

A final problem which is inherent in all raw material provenancing studies is that of secondary sources - i.e. materials which have travelled (usually by water action) far beyond their geological origin. There is some debate as to how serious this problem may be in the case of the Perigord region. Demars (1982: 72) for example has argued that virtually all flint supplies documented in his studies of Upper Palaeolithic sites in the north-east Dordogne region seem (from the condition of the adhering cortex) to have been derived from essentially primary or near-primary sources and he maintains that river gravel would have been largely avoided for tool manufacture, owing to the effects of battering and frost action on the nodules. Turq on the other hand (e.g. 1988a: 105-7; 1989a) regards stream or river gravels as one of the major sources of flint supplies. This is no doubt the most serious potential ambiguity in current provenancing studies. Against this, however, it should be remembered that most of the river terrace and alluvial deposits in the Perigord region have relatively localized catchment areas from which varied sources of flint could be derived. Clearly, secondary derivation of this kind cannot be invoked for materials which are known to have travelled against the direction of flow of rivers through the region (i.e. for materials which have travelled essentially from west to east) or for materials which have travelled along a north-south transect between the major river catchments (Geneste 1985, 1989a; Turq 1988a) (Fig. 5.5). The strongest argument against widespread use of secondary sources is provided by the highly specialized forms in which the artefacts manufactured from some of the more distant sources are normally represented within archaeological sites - as discussed further below. Hence, while the possibility of secondary sources should always be kept in mind, there are probably relatively few cases in practice where this could be invoked to explain the documented patterns of movement of raw materials in most Palaeolithic sites.

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