2017年7月对泥河湾盆地白洗沟遗址的抢救性发掘，清理面积约4 m²，出土石制品684件。¹⁴C测年显示，遗址距今约1.7万年。石制品以石片类数量最多，细石叶丰富，石核数量很少，另有少量无明显人工打制痕迹的搬入石块；石器少，仅有1件刮削器和2件锛状器，但经过精致修理且标准化程度高。对石制品的拼合研究及细石叶生产流程的分析显示，石片类产品形态、技术均展现出与细石核预制和修型的高度相关性；共发现19个拼合组；细石核技法属北方系或涌别系，技术稳定娴熟，多根据毛坯特点简化预制程序。综合泥河湾盆地发现的细石器遗存，以末次盛冰期的结束、全新世的到来可分为早、中、晚三个时期，分别对应细石叶技术萌芽、流行与衰落三个阶段。从早期到晚期，文化遗存构成渐趋丰富，人类的群体流动性逐渐降低，社会组织性较高。

The Baixigou site is located on the secondary terrace of Sanggan River in Yangyuan County, Hebei Province. A salvage archaeological excavation of an area of 4 m² in 2017 revealed a cultural layer of 6 cm thick, from which 991 artifacts were unearthed including 684 lithics and 307 animal bones. With a single cultural layer and thin accumulation, the Baixigou site has hardly been disturbed during its formation process. Artifacts are densely distributed around a hearth, including microblade products, flake tools, animal bones, ostrich eggshell beads and possible pigments. Different types of stone tools were made with specific raw materials, indicating that exploitation of raw materials was well-planned and systematic. The technology of wedge-shaped cores is close to the Yubetsu method where humans applied this technique skillfully and simplified core preparation procedure in consideration of blank characteristics. Chipped stones are most likely to be by-products of microblade production, of which 19 groups were refitted. There were only three tools, including one scraper and two adzes, but they are exquisite and reflect a trend towards standardization and craft specialization. Preliminary dating shows that the site was occupied around 17 kaBP. From the perspective of a forager-collector model, the Baixigou site is similar to a temporary field camp with a logistic mobility strategy. Activities carried out here are low-intensity, and thus few lithics have been used. Specialized tools such as adzes may reflect a connection between a residential camp and a more permanent field camp. To be specific, in addition to providing necessary tools for groups in the temporary field camp to reduce risk and maintain high mobility, groups in the residential camp provided specialized tools that met the needs of field camp. As a result, specialized tools are found in both types of camps. A significant number of microblade have been unearthed from the Nihewan Basin that shows a three-stage change corresponding to emergence, spread and gradual fading of microblade technology (i.e., early stage before and during Last Glacial Maximum; middle stage from post-LGM to pre-Holocene; and late stage during early Holocene). The process was consistent with climate fluctuations. Abundant archaeological remains indicate that group mobility of these hunter-gatherers slowly reduced with a tendency towards a more organized society.