关键词: 西沟湾1号地点, 怀来盆地, 拼合, 遗址形成, 剥片

Abstract:

The Xigouwan Paleolithic Locality 1(XGW1), situated in Zhuwoyuan village, Guanting town, Huailai county of Hebei Province, is a newly discovered Upper Paleolithic site which can be dated to 41~34 kaBP by AMS-¹⁴C dating. The archaeological remains were buried in the second terrace of the right bank of the Yongding River. This paleolithic locality was excavated from August to September, 2015, which exposed an area of 27 m², and 232 stone specimens were unearthed (including 218 stone artifacts and 14 natural pebbles). The lithic assemblage of XGW1 includes cores (n=8), flakes (n=141), chunks(n=68), a hammerstone (n=1), but there were no retouched pieces found. According to the lithic refitting practice, 41 stone artifacts can be combined into 14 refitted groups, which indicates a refitting success ratio of 18.8%. There are two different patterns (approaches) could be applied in the current refitting analysis, one is the pattern of “conjoining”, and the other is “joining”. Based on the lithic types, the refitted groups can be divided into four classes: cores and flakes (including whole flakes, debris and chunks), flakes and flakes (including debris and chunks), debris and chunks, and hammerstone and chunks. Combining the spatial distribution of the assemblage and the preservation status of the stone artifacts, the refitting patterns and relationships are effective for evaluating the site formation process and analyzing the flaking technique used by the ancient occupants.
As shown by the characteristics of stone artifacts and the flaking sequence of the cores-flakes refitted groups from XGW1, direct hard hammer percussion was the unique flaking technique, and the reduction strategy of cores (flake production without core preparation) is to look for the suitable platforms and working surfaces by changing flaking direction. Based on the spatial analysis of the stone artifacts, the average distance(d) of vertical movement of the refitted groups of XGW1 is relatively short (d<22 cm) from the view of the vertical distribution. As for the horizontal distribution, the average distance of the cores-flakes refitted groups (266 cm) and the flakes-flakes refitted groups (146 cm) is relatively long which indicates that there might be a complex behavior of moving the raw materials by human during the flaking process.
Based on the combination of different evidences, such as the size (mainly small ones) and weight (78.9% of them is lighter than 25 g) of the stone artifacts, the relatively high refitting success ratio (18.8%), the spatial distribution of refitted groups, the light degree of weathering and abrasion, etc, inferences could be concluded that the archaeological deposits of XWG1 had undergone light hydraulic disturbance, and the human behavior was the dominant reason for the formation of archaeological remains at this Late Paleolithic site.

Key words: Xigouwan locality 1, Huailai Basin, Refitting, Site formation, Flaking