怀来盆地西沟湾1号地点石制品的拼合研究

西沟湾1号地点位于河北省张家口市怀来县,AMS-¹⁴C测年显示其年代为距今4.1-3.4万年,属旧石器时代晚期。该地点埋藏于永定河右岸第二级阶地后缘,发掘面积约27 m²,出土石制品218件,其中41件可以拼合为14个拼合组,拼合成功率为18.8%;其拼合关系可分为拼对（conjoin）和拼接（join）两大类型,其中的组合形式主要包括石核与石片、石片与石片、石片与断块以及石锤与断块四大类。石制品的打击特征以及部分拼合组的剥片序列分析显示,西沟湾1号地点剥片方法为硬锤锤击法,石核剥片主要通过台面或剥片面的转向以实现对原料的多次开发和利用,剥片程度较高;综合各拼合组的空间分布状况,较高的石制品拼合率以及大多数石制品表面和边缘较为新鲜锋利的保存状态等信息,推测该地点在埋藏过程中受到的扰动程度较小,人类行为应是遗址形成的主要因素。

Refitting of stone artifacts from the Xigouwan Locality 1, Huailai Basin

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.