The pressure knapping technique develops circa 25,000 cal BP in Northeast Asia and excels at producing highly standardized microblades. Microblade pressure knapping spreads throughout most of Northeast Asia up to the Russian Arctic, and Alaska, in areas where the human presence was unknown. Swan Point CZ4b is the earliest uncontested evidence of human occupation of Alaska, at around 14,000 cal BP. It yields a pressure microblade component produced with the Yubetsu method, which is widespread in Northeast Asia during the Late Glacial period. Through the techno-functional analysis of 634 lithic pieces from this site, this study seeks to identify the techno-economical purposes for which the Yubetsu method was implemented. Data show that the microblade production system is related to an economy based on the planning of future needs, which is visible through blanks standardization, their overproduction, their functional versatility, and the segmentation of part of the chaîne opératoire. This expresses the efficiency and economic value of the microblade production system. The flexible use of pressure microblades identified at Swan Point CZ4b is also found in Japan, Korea, Kamchatka, and the North Baikal region, suggesting that their modes of use accompany the spread of early microblade pressure knapping over an immense territory across Beringia.

压力敲击技术在东北亚发展到约 25,000 cal BP，擅长生产高度标准化的微刀片。微刀片压力敲击遍及东北亚大部分地区，直至俄罗斯北极地区和阿拉斯加，这些地区的人类活动尚不为人所知。天鹅角 CZ4b 是人类占领阿拉斯加的最早、无可争议的证据，距今约 14,000 年。它产生了一种用涌别法生产的压力微叶片组件，这种方法在晚冰期的东北亚广泛传播。通过对该遗址的 634 块石器进行技术功能分析，本研究旨在确定实施 Yubetsu 方法的技术经济目的。数据显示，微刀片生产系统与基于未来需求规划的经济相关，这通过毛坯标准化、生产过剩、功能多功能性以及部分生产链的细分可见。这体现了微刀片生产系统的效率和经济价值。在天鹅角 CZ4b 发现的压力微刀片的灵活使用在日本、韩国、堪察加半岛和北贝加尔地区也被发现，这表明它们的使用模式伴随着早期微刀片压力敲击在白令陆桥广阔领土上的传播。