Here we report archaeological findings from the 2010 excavation of Helongdadong, an open-air site in the hinterland of the Changbaishan Mountains around 75 km east of the Changbaishan Tianchi volcano. Abundant lithic artefacts featured by blade and microblade technology were uncovered. Theses finding make Helongdadong one of the earliest evidence for microblade technology in Northeast China, and provides important insights into the emergence and spread of microblade technology in northeastern Asia.

Situated at the crossroads of Northeast China, the Korean Peninsula, and the Russian Far East, the Changbai Mountains show large quantities of lithic assemblages characterized by blade and microblade technology that plays a critical role in exploring emergence and spread of microblade technology and its relationship with climatic and environmental changes. Extensive utilization of obsidian and the toolkits themselves indicate a connection with other areas in northwest Asia. In the heart of the Changbai Mountains, the Helongdadong site (43°5′20.4″N, 128°57′20.9″E) is located on the third terrace of the left bank of the Tumen River, about 500 m north of Dadong village, Chongshan Town, Helong City, Jilin Province. It was discovered in 2007 and excavated in 2010. The deposits consist of seven layers with cultural remains from layers 1, 3, 4 and 5. From an area of 50 m², a total of 1253 lithic artifacts, 47 unmodified gravels, and 3 animal bones were unearthed. Obsidian is the predominant raw material. The technology is characterized by blade and microblade reduction. Toolkits mainly include burins, endscrapers, scrapers, and bifacial points etc. of which burins and endscrapers are primary tool types and are highly standardized in shape. Partially polished stone tools discovered in Layer 4 constitute one of the earliest dated edge-polished stone tools in China. From Layer 4, the main cultural layer of Helongdadong, lithic artifacts are spatially concentrated, suggestive of an in-situ burial. The spatial distribution of the lithics also indicate human activity such as procurement, blank production, modification and tool manufacture. A radiocarbon date of 21350±120 (25900~25340 BP cal) was obtained for Layer 4, corresponding to the initial stage of the Last Glacial Maximum. Preliminary results of Optically Stimulated Luminescence dating further suggests that the dates of layers 5 and 4 were not earlier than 28 kaBP, and Layer 3 around 15 kaBP. The well-preserved, stratified and dated contexts of the site provide essential information for building a chronostratigraphic framework in the Changbai Mountains and make it possible to perform a comparative analysis of lithic technology in northwest Asia during the Upper Paleolithic.