Lithic raw material economy in the Hailang River Basin, Northeast China during Marine Isotope Stage 2

Studies of lithic raw material economies yield crucial insights into prehistoric human adaptive strategies. This paper presents an integrated analysis of lithic raw material economy at three newly excavated sites (Dalongtoushan, Xiaolongtoushan, and Yanglin Xishan) in the Hailang River Basin, which date to Marine Isotope Stage 2 (MIS 2) and are situated on the northern margin of the Changbai Mountains in Northeast China. By integrating petrographic identification, provenance tracing, and techno-typological characterization, we reveal a flexible ternary exploitation strategy shaped by raw material quality, abundance, and accessibility. This strategy balanced expedient use of local basalt, curated use of non-local obsidian, and flexible exploitation of local tuff and rhyolite. At the intra- and inter-regional scales, we further identified multi-level interactions between raw material exploitation, lithic technology, and environmental context across the Changbai Mountains and its vicinity. Collectively, this study offers empirical insights into hunter-gatherers’ adaptive flexibility in MIS 2 Northeast Asia.